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nucmag.com<br />
<strong>2018</strong><br />
2<br />
81<br />
Gas Cooled<br />
Reactor Development<br />
in China<br />
85 ı Environment and Safety<br />
Severe Accident Safety Research for Reactor Buildings<br />
95 ı Operation and New Build<br />
Knowledge Management and TRIZ for Safe Shutdown Capability<br />
ISSN · 1431-5254<br />
24.– €<br />
104 ı Decommissioning and Waste Management<br />
Corrosion Processes of Alloyed Steels in Salt Solutions<br />
134 ı Nuclear Today<br />
Playing Politics with Nuclear is all Part of the Game
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
Some Questions and Answers<br />
About Energy<br />
Dear Reader, The question is always on the agenda whether people are really aware about facts on energy.<br />
The following energy quiz with 12 questions should point out some interesting facts. The answers are given on page 132<br />
of this issue of <strong>atw</strong>.<br />
1. True or false:<br />
The global energy demand will<br />
decrease in the next decades!<br />
a. True<br />
b. False<br />
2. True or false:<br />
The global electricity demand will<br />
decrease in the next decades!<br />
a. True<br />
b. False<br />
3. True or false:<br />
The global coal production<br />
is always decreasing!<br />
a. True<br />
b. False<br />
4. What percentage of world’s electricity<br />
production was produced from nuclear<br />
in 2017?<br />
a. 1 %<br />
b. 6 %<br />
c. 11 %<br />
d. 20 %<br />
8. Which technology has the lowest<br />
CO 2 footprint?<br />
a. Photovoltaics<br />
b. Wind<br />
c. Nuclear<br />
d. Hydropower<br />
9. What energy source has Bill Gates<br />
invested in, and championed, over the<br />
last few years?<br />
a. Nuclear power<br />
b. Photovoltaics<br />
c. Wind energy<br />
d. Tidal energy<br />
10. What energy source has the smallest<br />
number of lost lifetime-days<br />
(due to health hazards and accidents)<br />
per kilowatt-hour produced?<br />
a. Coal<br />
b. Natural gas<br />
c. Wind<br />
d. Nuclear power<br />
11. What subjects someone<br />
to the most radiation?<br />
71<br />
EDITORIAL<br />
5. What percentage of world’s electricity<br />
production was produced from wind plus<br />
solar in 2017?<br />
a. 1 %<br />
b. 5 %<br />
c. 10 %<br />
d. 20 %<br />
6. Which country has the most<br />
fossil fuel resources?<br />
a. Saudi Arabia<br />
b. Russia<br />
c. United States of America<br />
d. China<br />
e. EU<br />
7. What country/region will emit the most<br />
carbon dioxide in <strong>2018</strong>?<br />
a. Living next to a nuclear power plant.<br />
b. Flying from Europe to other continents<br />
c. Eating a 250 g bag of potato chips<br />
every day<br />
d. Living in Guarapari, Brazil<br />
12. True or false:<br />
The number of nuclear power plants<br />
worldwide will decrease in the future.<br />
a. True<br />
b. False<br />
Christopher Weßelmann<br />
– Editor in Chief –<br />
a. United States of America<br />
b. Nigeria<br />
c. EU<br />
d. China<br />
Editorial<br />
Some Questions and Answers About Energy
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
72<br />
EDITORIAL<br />
Einige Fragen und Antworten<br />
zum Thema Energie<br />
Liebe Leserin, lieber Leser, Diskussion über das Thema Energie wird häufig die Frage aufgeworfen, inwieweit<br />
diese von Fakten bestimmt wird bzw. die Fakten überhaupt bekannt sind. Das folgende Energiequiz soll mit seinen<br />
12 Fragen einige interessante Fakten aufzeigen. Die Antworten finden Sie auf Seite 132 dieser Ausgabe der <strong>atw</strong>.<br />
1. Richtig oder falsch:<br />
Der globale Energiebedarf wird<br />
in den nächsten Jahrzehnten sinken!<br />
a. Wahr<br />
b. Falsch<br />
2. Richtig oder falsch:<br />
Der weltweite Strombedarf wird<br />
in den nächsten Jahrzehnten sinken!<br />
a. Wahr<br />
b. Falsch<br />
3. Richtig oder falsch:<br />
Die weltweite Kohleförderung nimmt ab!<br />
8. Welche Technologie hat den niedrigsten<br />
CO 2 -Fußabdruck?<br />
a. Photovoltaik<br />
b. Wind<br />
c. Kernenergie<br />
d. Wasserkraft<br />
9. In welche Energiequelle hat Bill Gates<br />
in den letzten Jahren investiert und sich<br />
dafür öffentlich eingesetzt?<br />
a. Kernkraft<br />
b. Photovoltaik<br />
c. Windenergie<br />
d. Gezeitenenergie<br />
a. Wahr<br />
b. Falsch<br />
4. Welchen Anteil hatte die Kernenergie<br />
an der weltweiten Stromproduktion<br />
im Jahr 2017?<br />
a. 1 %<br />
b. 6 %<br />
c. 11 %<br />
d. 20 %<br />
5. Welchen Anteil hatten Wind und Sonne<br />
an der weltweiten Stromproduktion<br />
im Jahr 2017?<br />
a. 1 %<br />
b. 5 %<br />
c. 10 %<br />
d. 20 %<br />
6. Welches Land verfügt über die größten<br />
fossilen Energieressourcen?<br />
a. Saudi-Arabien<br />
b. Russland<br />
c. Vereinigte Staaten von Amerika<br />
d. China<br />
e. EU<br />
7. Welches Land bzw. welche Region<br />
wird <strong>2018</strong> die höchsten Kohlendioxidemissionen<br />
verzeichnen?<br />
a. Vereinigte Staaten von Amerika<br />
b. Nigeria<br />
c. EU<br />
d. China<br />
10. Welche Energiequelle verzeichnet die<br />
geringste Anzahl an Ausfalltagen<br />
(aufgrund von Gesundheitsgefahren<br />
und Unfällen) pro produzierter Kilowattstunde?<br />
a. Kohle<br />
b. Erdgas<br />
c. Wind<br />
d. Kernkraft<br />
11. Was verursacht die höchste<br />
Strahlenbelastung?<br />
a. Wohnen neben einem Kernkraftwerk.<br />
b. Fliegen von Europa<br />
zu anderen Kontinenten<br />
c. Täglich 250 g Chips essen<br />
d. Leben in Guarapari, Brasilien<br />
12. Richtig oder falsch:<br />
Die Zahl der Kernkraftwerke weltweit<br />
wird in Zukunft abnehmen.<br />
a. Wahr<br />
b. Falsch<br />
Christopher Weßelmann<br />
– Chefredakteur –<br />
Editorial<br />
Einige Fragen und Antworten zum Thema Energie
Kommunikation und<br />
Training für Kerntechnik<br />
Suchen Sie die passende Weiter bildungsmaßnahme<br />
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Die INFORUM-Seminare bieten nützliche Kenntnisse, die Sie und Ihre Mitarbeiterinnen<br />
und Mitarbeiter in der täglichen Praxis unterstützen.<br />
Wählen Sie aus folgenden Themen:<br />
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a Nuclear English<br />
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Seminar Termin Ort<br />
Atomrecht –<br />
Das Recht der radioaktiven Abfälle<br />
Erfolgreicher Wissenstransfer in der Kerntechnik<br />
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Advancing Your Nuclear English<br />
(Aufbaukurs)<br />
Atomrecht – Ihr Weg<br />
durch Genehmigungs- und Aufsichtsverfahren<br />
Atomrecht – Navigation<br />
im internationalen nuklearen Vertragsrecht<br />
Das neue Strahlenschutzgesetz –<br />
Folgen für Recht und Praxis<br />
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21.03. - 22.03.<strong>2018</strong> Berlin<br />
11.04. - 12.04.<strong>2018</strong><br />
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Export kerntechnischer Produkte und<br />
20.06. - 21.06.<strong>2018</strong> Berlin<br />
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Stilllegung, Rückbau und Entsorgung – 24.09. - 25.09.<strong>2018</strong> Berlin<br />
Recht und Praxis<br />
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International verstehen und verstanden werden<br />
Public Hearing Workshop –<br />
Öffentliche Anhörungen erfolgreich meistern<br />
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im gesellschaftlichen Diskurs<br />
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<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
74<br />
Issue 2<br />
February<br />
CONTENTS<br />
81<br />
Gas Cooled<br />
Reactor Development<br />
in China<br />
| | Outside view of the two boiling water reactors at the Olkiluoto site in Finland. The reactors with a gross electric output of 910 MWe each<br />
are successfully operated by Teollisuuden Voima Oyj – TVO. Ever since the early 1990s, the OL1 and OL2 capacity factors have remained<br />
between 93 and 97 percent. (Courtesy: TVO)<br />
Editorial<br />
Some Questions and Answers<br />
About Energy 71<br />
Einige Fragen und Antworten<br />
zum Thema Energie 72<br />
Abstracts | English 76<br />
Abstracts | German 77<br />
Calendar . . . . . . . . . . . . . . . . . . . . . . . .80<br />
Energy Policy, Economy and Law<br />
Development of High Temperature<br />
Gas Cooled Reactor in China 81<br />
Wentao Guo and Michael Schorer<br />
Spotlight on Nuclear Law<br />
The Liability According to § 26 of the<br />
German Atomic Energy Act – A Wallflower? 84<br />
Die Haftung nach § 26 AtG –<br />
ein Mauerblümchen? 84<br />
Christian Raetzke<br />
81<br />
| | The construction of Shidao Bay HTGR.<br />
Inside Nuclear with NucNet<br />
WANO to Increase Focus on New Nuclear as<br />
Industry’s Centre of Gravity Shifts Towards Asia 78<br />
85<br />
NucNet<br />
| | COCOSYS nodalisation scheme.<br />
DAtF Notes. . . . . . . . . . . . . . . . . . . . . . 79<br />
Contents
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
Environment and Safety<br />
Investigation of Conditions Inside the Reactor<br />
Building Annulus of a PWR Plant of KONVOI<br />
Type in Case of Severe Accidents with Increased<br />
Containment Leakages 85<br />
Ivan Bakalov and Martin Sonnenkalb<br />
Sensitivity Analysis of MIDAS Tests<br />
Using SPACE Code: Effect of Nodalization 90<br />
Shin Eom, Seung-Jong Oh and Aya Diab<br />
75<br />
CONTENTS<br />
90<br />
Operation and New Build<br />
The Application of Knowledge Management<br />
and TRIZ for solving the Safe Shutdown Capability<br />
in Case of Fire Alarms in Nuclear Power Plants 95<br />
Chia-Nan Wang, Hsin-Po Chen, Ming-Hsien Hsueh and Fong-Li Chin<br />
95<br />
| | Isometric View of the MIDAS Facility.<br />
| | Application of knowledge management and TRIZ.<br />
Decommissioning and Waste Management<br />
Corrosion Processes of Alloyed Steels<br />
in Salt Solutions 104<br />
Bernhard Kienzler<br />
Research and Innovation<br />
Design and Development of a Radio eco logical<br />
Domestic User Friendly Code for Calculation<br />
of Radiation Doses and Concentration<br />
due to Airborn Radio nuclides Release During<br />
the Accidental and Normal Operation<br />
in Nuclear Installations 111<br />
|104<br />
111<br />
| | Localized corrosion phenomena of steel 1.4306.<br />
Events<br />
Event Report:<br />
Nuklearforum Schweiz – Future Management<br />
– Key Solutions for Nuclear Facilities 121<br />
Event Report:<br />
Nuklearforum Schweiz – Zukunftsmanagement<br />
– zentrale Lösungsansätze für Kernanlagen 121<br />
Matthias Rey<br />
KTG Inside . . . . . . . . . . . . . . . . . . . . . . 123<br />
News . . . . . . . . . . . . . . . . . . . . . . . . . 129<br />
Nuclear Today<br />
Playing Politics with Nuclear<br />
is All Part of the Game 134<br />
John Shepherd<br />
Imprint 110<br />
| Summary of Code Algorithms.<br />
A. Haghighi Shad, D. Masti, M. Athari Allaf, K. Sepanloo, S.A.H. Feghhi<br />
and R. Khodadadi<br />
AMNT <strong>2018</strong>: Registration Form . . . . . . . . . . . Insert<br />
Contents
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
76<br />
ABSTRACTS | ENGLISH<br />
WANO to Increase Focus on New Nuclear<br />
as Industry’s Centre of Gravity Shifts<br />
Towards Asia<br />
NucNet | Page 78<br />
The World Association of Nuclear Operators<br />
(WANO) intends to focus more on new nuclear units<br />
coming into operation around the world as the<br />
“ centre of gravity” in the industry shifts from the US<br />
and Europe to the Middle East and Asia. The<br />
organisation’s chief executive officer, Peter Prozesky,<br />
told NucNet that new-build projects in China, India,<br />
Turkey and the United Arab Emirates are giving<br />
WANO the opportunity to make sure those countries<br />
start the operational life of their new units “in a very<br />
positive way”. In supporting countries with new<br />
units beginning operation, WANO is working more<br />
closely with the International Atomic Energy Agency<br />
(IAEA). One of the IAEA’s tasks is to help emerging<br />
nuclear countries develop the infrastructure and<br />
capability they need to have nuclear power as part of<br />
their energy mix.<br />
Development of High Temperature Gas<br />
Cooled Reactor in China<br />
Wentao Guo and Michael Schorer | Page 81<br />
High temperature gas cooled reactor (HTGR) is one<br />
of the six Generation IV reactor types put forward<br />
by Generation IV International Forum (GIF) in<br />
20<strong>02</strong>. This type of reactor has high outlet temperature.<br />
It uses Helium as coolant and graphite as<br />
moderator. Pebble fuel and ceramic reactor core are<br />
adopted. Inherit safety, good economy, high generating<br />
efficiency are the advantages of HTGR.<br />
According to the comprehensive evaluation from<br />
the international nuclear community, HTGR has<br />
already been given the priority to the research and<br />
development for commercial use. A demonstration<br />
project of the High Temperature Reactor-Pebblebed<br />
Modules (HTR-PM) in Shidao Bay nuclear<br />
power plant in China is under construction. In this<br />
paper, the development history of HTGR in China<br />
and the current situation of HTR-PM will be introduced.<br />
The experiences from China may be taken as<br />
a reference by the international nuclear community.<br />
The Liability According to § 26 of the<br />
German Atomic Energy Act – A Wallflower?<br />
Christian Raetzke | Page 84<br />
According to German law, liability for damage<br />
caused by radioactivity can arise from several<br />
regulation. In most cases, liability under the Paris<br />
Convention on Third Party Liability in the Field of<br />
Nuclear Energy, which applies in the field of nuclear<br />
power, is at the forefront of discussion. According to<br />
§ 26 of the German Atomic Energy Act, liability is<br />
somewhat in the shadow of the Paris Convention. It<br />
applies to the handling of radioactivity in medicine,<br />
research and industry (e. g. for test emitters) as well<br />
as activities involving natural and depleted uranium<br />
and nuclear fusion. The article outlines the basic<br />
elements of liability under Section 26 of the German<br />
Atomic Energy Act, which may become increasingly<br />
important in future due to recent developments<br />
such as the phasing out of nuclear power in<br />
Germany.<br />
Investigation of Conditions Inside the<br />
Reactor Building Annulus of a PWR Plant of<br />
KONVOI Type in Case of Severe Accidents<br />
with Increased Containment Leakages<br />
Ivan Bakalov and Martin Sonnenkalb | Page 85<br />
Improvements of the implemented severe accident<br />
management (SAM) concepts have been done in all<br />
operating German NPPs after the Fukushima Daiichi<br />
accidents following recommendations of the<br />
German Reactor Safety Commission (RSK) and as a<br />
result of the stress test being performed. The<br />
efficiency of newly developed severe accident<br />
management guidelines (SAMG) for a PWR KONVOI<br />
reference plant related to the mitigation of challenging<br />
conditions inside the reactor building (RB)<br />
annulus due to increased containment leakages<br />
during severe accidents have been assessed. Based<br />
on two representative severe accident scenarios the<br />
releases of both hydrogen and radionuclides into the<br />
RB annulus have been predicted with different<br />
boundary conditions. The accident scenarios have<br />
been analysed without and with the impact of<br />
several SAM measures (already planned or proposed<br />
in addition), which turned out to be efficient to<br />
mitigate the consequences. The work was done<br />
within the frame of a research project financially<br />
supported by the Federal Ministry BMUB.<br />
Sensitivity Analysis of MIDAS Tests Using<br />
SPACE Code: Effect of Nodalization<br />
Shin Eom, Seung-Jong Oh and Aya Diab | Page 90<br />
The nodalization sensitivity analysis for the ECCS<br />
(Emergency Core Cooling System) bypass phenomena<br />
was performed using the SPACE (Safety<br />
and Performance Analysis CodE) thermal hydraulic<br />
analysis computer code. The results of MIDAS<br />
(Multi- dimensional Investigation in Downcomer<br />
Annulus Simulation) test were used. The MIDAS<br />
test was conducted by the KAERI (Korea Atomic<br />
Energy Research Institute) for the performance<br />
evaluation of the ECC (Emergency Core Cooling)<br />
bypass phenomenon in the DVI (Direct Vessel<br />
Injection) system. The main aim of this study is to<br />
examine the sensitivity of the SPACE code results<br />
to the number of thermal hydraulic channels<br />
used to model the annulus region in the MIDAS<br />
experiment. The numerical model involves three<br />
nodalization cases (4, 6, and 12 channels) and<br />
the result show that the effect of nodalization<br />
on the bypass fraction for the high steam flow rate<br />
MIDAS tests is minimal. For computational<br />
efficiency, a 4 channel representation is recommended<br />
for the SPACE code nodalization. For the<br />
low steam flow rate tests, the SPACE code overpredicts<br />
the bypass fraction irrespective of the<br />
nodalization finesse. The over- prediction at low<br />
steam flow may be attributed to the difficulty<br />
to accurately represent the flow regime in the<br />
vicinity of the broken cold leg.<br />
The Application of Knowledge<br />
Management and TRIZ for solving<br />
the Safe Shutdown Capability in Case of<br />
Fire Alarms in Nuclear Power Plants<br />
Chia-Nan Wang, Hsin-Po Chen,<br />
Ming-Hsien Hsueh and Fong-Li Chin | Page 95<br />
The Fukushima nuclear disaster in 2011 has raised<br />
widespread concern over the safety of nuclear<br />
power plants. This study employed knowledge<br />
management in conjunction with the Teoriya<br />
Resheniya Izobreatatelskih Zadatch (TRIZ) method<br />
in the formulation of a database to facilitate the<br />
evaluation of post-fire safe shutdown capability<br />
with the aim of safeguarding nuclear facilities in the<br />
event of fire. The proposed approach is meant to<br />
bring facilities in line with US Nuclear Regulatory<br />
Commission (NRC) standards. When implemented<br />
in a case study of an Asian nuclear power plant, our<br />
method proved highly effective in the detection of<br />
22 cables that fell short of regulatory requirements,<br />
thereby reducing 850,000 paths to 0. This study<br />
could serve as reference for industry and academia<br />
in the development of systematic approaches to the<br />
upgrading of nuclear power plants.<br />
Corrosion Processes of Alloyed Steels<br />
in Salt Solutions<br />
Bernhard Kienzler | Page 104<br />
A summary is given of the corrosion experiments<br />
with alloyed Cr-Ni steels in salt solutions performed<br />
at Research Centre Karlsruhe (today KIT), Institute<br />
for Nuclear Waste Disposal (INE) in the period<br />
between 1980 and 2004. Alloyed steels show<br />
significantly lower general corrosion in comparison<br />
to carbon steels. However, especially in salt brines<br />
the protective Cr oxide layers on the surfaces of<br />
these steels are disturbed and localized corrosion<br />
takes place. Data on general corrosion rates, and<br />
findings of pitting, crevice and stress corrosion<br />
cracking are presented.<br />
Design and Development of a Radioecological<br />
Domestic User Friendly Code for<br />
Calculation of Radiation Doses and Concentration<br />
due to Airborn Radionuclides<br />
Release During the Accidental and Normal<br />
Operation in Nuclear Installations<br />
A. Haghighi Shad, D. Masti,<br />
M. Athari Allaf, K. Sepanloo,<br />
S.A.H. Feghhi and R. Khodadadi | Page 111<br />
A domestic user friendly dynamic radiological dose<br />
and model has been developed to estimate radiation<br />
doses and stochastic risks due to atmospheric and<br />
liquid discharges of radionuclides in the case of a<br />
nuclear reactor accident and normal operation. In<br />
addition to individual doses from different pathways<br />
for different age groups, collective doses and<br />
stochastic risks can be calculated by the developed<br />
domestic user friendly KIANA Advance Computational<br />
Computer Code and model. The current Code<br />
can be coupled to any long-range atmospheric<br />
dispersion/short term model which can calculate<br />
radionuclide concentrations in air and on the<br />
ground and in the water surfaces predetermined<br />
time intervals or measurement data.<br />
Event Report: Future Management –<br />
Key Solutions for Nuclear Facilities<br />
Matthias Rey | Page 121<br />
Future management requires careful planning and<br />
knowledge of what options are available, how far<br />
optimizations make sense and which measures and<br />
process changes have already proven themselves<br />
elsewhere. The 2017 advanced course of the Swiss<br />
Nuclear Forum took up this topic. On the first day<br />
of the course, the focus was on solutions for<br />
optimizing system operation and maintenance. The<br />
second day focused on the employees in their<br />
changing environment. As a novelty this year, the<br />
topics of the morning input presentations were<br />
discussed in depth in workshops on both afternoons.<br />
Playing Politics with Nuclear is all Part<br />
of the Game<br />
John Shepherd | Page 134<br />
If a week is a long time in politics – a statement<br />
attributed to former British prime minister Harold<br />
Wilson – then what about a month, or several<br />
months – a period relevant for the use of nuclear<br />
power? The nuclear industry has long accepted that<br />
it can be used as a political football, to be kicked into<br />
goal or off the pitch completely depending on the<br />
situation at hand. Our industry therefore has power<br />
in the political sense too, but with power comes<br />
responsibility – nuclear leaders know that only too<br />
well and now is as good as time as ever to lead by<br />
example.<br />
Abstracts | English
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
WANO wird sich mit der Verlagerung der<br />
Aktivitäten nach Asien verstärkt auf den<br />
Kernkraftwerksneubau konzentrieren<br />
NucNet | Seite 78<br />
Die World Association of Nuclear Operators<br />
( WANO) will sich verstärkt auf Kernkraftwerksneubauten<br />
konzentrieren, da sich der „Schwerpunkt“<br />
der Branche von den USA und Europa in den Nahen<br />
Osten und nach Asien verlagert. Peter Prozesky,<br />
Chief Executive Officer von WANO, erläuterte, dass<br />
Neubauprojekte in China, Indien, der Türkei und<br />
den Vereinigten Arabischen Emiraten WANO die<br />
Möglichkeit geben, dass diese Länder mit den<br />
Erfahrungen von WANO in die Kernenergie einsteigen.<br />
Bei der Unterstützung von Ländern, in<br />
denen neue Anlagen in Betrieb genommen werden,<br />
arbeitet WANO eng mit der Internationalen Atomenergie-Organisation<br />
(IAEO) zusammen. Eine der<br />
Aufgaben der IAEO besteht darin, die zuküftigen<br />
Nuklearstaaten darin zu unterstützen, die Infrastruktur<br />
und das Know-how zu entwickeln, das<br />
sie benötigen, um die Kernenergie als Teil ihres<br />
Energiemixes zu nutzen.<br />
Entwicklung des gasgekühlten<br />
Hochtemperaturreaktors in China<br />
Wentao Guo und Michael Schorer | Seite 81<br />
Der gasgekühlte Hochtemperaturreaktor (HTGR) ist<br />
einer von sechs Reaktortypen der Generation IV, die<br />
20<strong>02</strong> vom Generation IV International Forum (GIF)<br />
vorgestellt wurde. Charakteristisch für diesen Reaktortyp<br />
sind die hohe Kühlmittelaustrittstem peratur<br />
aus dem Reaktor, Helium als Kühlmittel, Graphit<br />
als Moderator, kugelförmige Brenn elemente sowie<br />
keramischer Reaktorkernein bauten. Vorteile von<br />
HTGR sind inhärente Sicherheit, Wirtschaftlichkeit<br />
sowie hohe Effizienz der Brennstoffnutzung. Nach<br />
einer umfassenden Eva luierung durch hat die Entwicklung<br />
von HTGR bis hin zur kommerziellen<br />
Nutzung Priorität. Ein Demonstrationsprojekt für<br />
einen HTR-Modul reaktor befindet sich am Standort<br />
Shidao Bay in China in Bau. In diesem Beitrag<br />
werden die Entwicklungsgeschichte von HTGR in<br />
China und die aktuelle Situation der HTR-PM-<br />
Projekte vor gestellt. Die Erfahrungen aus China sind<br />
eine international nutzbare Referenz.<br />
Die Haftung nach § 26 AtG –<br />
ein Mauerblümchen?<br />
Christian Raetzke | Seite 84<br />
Die Haftung für Schäden aus Radioaktivität kann<br />
sich nach deutschem Recht aus mehreren Quellen<br />
ergeben. In der Diskussion steht meist die Haftung<br />
nach dem Pariser Übereinkommen (PÜ) im Vordergrund,<br />
die im Bereich der Kernenergie gilt. Etwas<br />
im Schatten des PÜ steht die Haftung nach § 26 AtG.<br />
Sie gilt für den Umgang mit Radioaktivität im<br />
Bereich der Medizin, Forschung und Industrie<br />
( etwa bei Prüfstrahlern) sowie für Aktivitäten rund<br />
um natürliches und abgereichertes Uran und für die<br />
Kernfusion. Der Artikel skizziert die Grund elemente<br />
der Haftung nach § 26 AtG, die aufgrund jüngerer<br />
Entwicklungen wie dem Kernenergieausstieg in<br />
Deutschland möglicherweise künftig an Bedeutung<br />
gewinnen wird.<br />
Untersuchungen zu den Zuständen im<br />
Ringraum des Reaktorgebäudes eine DWR<br />
vom Typ KONVOI im Falle von schweren<br />
Störfällen mit erhöhten Leckagen aus dem<br />
Containment<br />
Ivan Bakalov and Martin Sonnenkalb | Seite 85<br />
Die anlageninternen Notfallschutzkonzepte der in<br />
Betrieb befindlichen KKW in Deutschland wurden<br />
nach den Unfällen in Fukushima Daiichi verbessert<br />
und damit Empfehlungen der Reaktorsicherheitskommission<br />
(RSK) und neue Erkenntnisse aus den<br />
Stress Tests umgesetzt. Die Wirksamkeit von neu<br />
entwickelten Maßnahmen des mitigativen Notfallschutzes<br />
für eine DWR-Referenzanlage vom Typ<br />
KONVOI hinsichtlich der Zustände im Ringraum<br />
des Reaktorgebäudes bei erhöhten Leckagen aus<br />
dem Containment während schwerer Störfälle<br />
wurde analysiert. Die Freisetzung von Wasserstoff<br />
und Radionukliden in den Ringraum des Reaktorgebäudes<br />
wurde an Hand von zwei repräsentativen<br />
schweren Störfallszenarien unter der Annahme<br />
unterschiedlicher Randbedingungen untersucht.<br />
Die Analysen wurden ohne und mit mitigativen<br />
Notfallmaßnahmen (bereits umgesetzte oder<br />
zusätzliche Maßnahmen) durchgeführt, und die<br />
Ergebnisse bestätigten die Wirksamkeit aller Maßnahmen.<br />
Die Arbeiten wurden im Rahmen eines<br />
Forschungsprojektes der GRS finanziell unterstützt<br />
vom BMUB durchgeführt.<br />
Sensitivitätsanalyse von MIDAS-Tests mit<br />
SPACE-Code: Auswirkung der Nodalisierung<br />
Shin Eom, Seung-Jong Oh und Aya Diab | Seite 90<br />
Die Sensitivitätsanalyse zur Nodalisierung für die<br />
Bypass-Phänomene des ECCS (Emergency Core<br />
Cooling System) wurde mit Hilfe des thermo hydraulischen<br />
Analyse-Computercodes SPACE ( Safety and<br />
Performance Analysis CodE) durchgeführt. Dazu<br />
wurden die Ergebnisse des MIDAS-Tests (Multidimensional<br />
Investigation in Downcomer Annulus<br />
Simulation) verwendet. Der MIDAS-Test wurde vom<br />
KAERI (Korea Atomic Energy Research Institute) zur<br />
Leistungsbewertung des ECC ( Emergency Core<br />
Cooling) Bypass-Phänomens im DVI (Direct Vessel<br />
Injection) System durchgeführt. Das Hauptziel dieser<br />
Studie ist es, die Sensitivität der SPACE-Code-Ergebnisse<br />
für die thermo hydrau lischen Unterkanäle zu<br />
untersuchen, die zur Modellierung des Ringraums im<br />
MIDAS- Experiment verwendet werden. Aus Gründen<br />
der Rechen effizienz wird für die SPACE-Code-<br />
Nodalisierung eine 4-Kanal-Darstellung empfohlen.<br />
Knowledge Management und TRIZ<br />
für die Sicherstellung der Abschaltfähigkeit<br />
bei Feueralarmen in Kernkraftwerken<br />
Chia-Nan Wang, Hsin-Po Chen,<br />
Ming-Hsien Hsueh und Fong-Li Chin | Seite 95<br />
Die Katastrophe von Fukushima im Jahr 2011 hat<br />
die Frage nach der Sicherheit von Kernkraftwerken<br />
erneut gestellt. In dieser Studie wurde Wissensmanagement<br />
in Verbindung mit der Teoriya Resheniya<br />
Izobreatatelskih Zadatch (TRIZ) Methode bei der<br />
Formulierung einer Datenbank eingesetzt, um die<br />
Bewertung der Fähigkeit zur sicheren Abschaltung<br />
nach einem Brand in einem Kernkraftwerk zu<br />
ermöglichen. Der vorgeschlagene Ansatz zielt<br />
darauf ab, die Anlagen mit den Standards der<br />
US Nuclear Regulatory Commission (NRC) in<br />
Einklang zu bringen. Bei der Implementierung in<br />
einer Fallstudie eines asiatischen Kernkraftwerks<br />
erwies sich die Methode als sehr effektiv bei der<br />
Feststellung von 22 Kabeln, die nicht den vorgegebenen<br />
Anforderungen entsprachen, wodurch<br />
850.000 mögliche Ereignispfade auf 0 reduziert<br />
wurden. Diese Studie kann auch als Referenz<br />
dienen für die Entwicklung systematischer Ansätze<br />
zur weiteren Modernisierung von Kernkraftwerken.<br />
Korrosionprozesse legierter Stähle<br />
in Salzlösungen<br />
Bernhard Kienzler | Seite 104<br />
Es wird eine Zusammenfassung der Experimente<br />
zur Korrosion von legierten Cr-Ni Stählen in<br />
Salzlösungen vorgestellt. Die Experimente wurden<br />
Im Forschungszentrum Karlsruhe (heute KIT),<br />
Institut für Nukleare Entsorgung (INE) im Zeitraum<br />
zwischen 1980 und 2004 durchgeführt. Legierte<br />
Stähle zeigten eine deutlich geringere Flächenkorrosion<br />
im Vergleich zu den ebenfalls untersuchten<br />
Kohlenstoffstählen. Jedoch findet in den<br />
Salzlösungen eine Störung der Korrosionsschutzschichten<br />
aus Cr-Oxiden auf den Stahloberflächen<br />
statt, die zu lokalen Korrosionsprozessen führt.<br />
Flächenkorrosionsraten und die Beobachtungen<br />
hinsichtlich Lochfrass-, Spalt- und Spannungsrißkorrosion<br />
werden aufgezeigt.<br />
Entwicklung eines Codes zur Berechnung<br />
der Strahlendosis und -konzentration bei<br />
Freisetzung von luftgetragenen Radionukliden<br />
während des unfallbedingten<br />
und normalen Betriebes kerntechnischer<br />
Anlagen<br />
A. Haghighi Shad, D. Masti,<br />
M. Athari Allaf, K. Sepanloo,<br />
S.A.H. Feghhi und R. Khodadadi | Seite 111<br />
Zur Abschätzung von Strahlendosen und stochastischen<br />
Risiken durch atmosphärische und flüssige<br />
Radionuklidemissionen bei einem Reaktorunfall<br />
und im Normalbetrieb wurde ein benutzerfreundliches<br />
dynamisches radiologisches Freisetzungs- und<br />
Dosismodell entwickelt. Zusätzlich zu den Einzeldosen<br />
aus verschiedenen Pfaden für verschiedene<br />
Nuklide können Kollektivdosen und stochastische<br />
Risiken mit Hilfe des entwickelten benutzerfreundlichen<br />
KIANA Advance Computational Computer<br />
Codes und Modells berechnet werden. Der aktuelle<br />
Code kann mit jedem weiträumigen atmosphärischen<br />
Ausbreitungs-/Kurzzeitmodell gekoppelt<br />
werden, mit dem Radionuklidkonzentrationen<br />
in der Luft und am Boden und in Gewässern<br />
berechnet werden können.<br />
Tagungsbericht: Zukunftsmanagement –<br />
zentrale Lösungsansätze für Kernanlagen<br />
Matthias Rey | Seite 121<br />
Zukunftsmanagement erfordert sorgfältige Planung<br />
und Wissen darüber, welche Optionen zur Verfügung<br />
stehen, wieweit Optimierungen sinnvoll<br />
sind und welche Maßnahmen und Prozessänderungen<br />
sich allenfalls bereits anderswo<br />
bewährt haben. Der Vertiefungskurs 2017 des<br />
Nuklearforums Schweiz nahm diese Thematik auf.<br />
Im Zentrum standen Lösungsansätze zum Optimieren<br />
von Systembetrieb und Instandhaltung<br />
sowie die Mitarbeitenden in ihrer sich verändernden<br />
Umwelt. Als Novum wurden die Themen<br />
der Inputreferate des Vormittags in Workshops<br />
vertieft diskutiert.<br />
Mit der Kernenergie zu spielen<br />
ist Teil der Politik<br />
John Shepherd | Seite 134<br />
Eine Woche ist in der Politik eine lange Zeit! Dieser<br />
Satz wird dem ehemaligen britischen Premierminister<br />
Harold Wilson zugeschrieben. Was ist<br />
dann mit einem Monat oder mehreren Monaten,<br />
wie sie für eine langfristige Technologie wie der<br />
Kernenergie bestimmend sind? Die kerntechnische<br />
Industrie hat längst akzeptiert, dass sie als politischer<br />
Spielball genutzt werden kann, um je nach<br />
Situation ins Tor oder vom Spielfeld geschossen zu<br />
werden. „Nuklearpolitiker“ wissen, dass Entscheidungen<br />
zur Kernenergie nicht nur „Macht“<br />
bedeuten, sondern auch Verantwortung. Heute<br />
geht es deshalb darum hier mit gutem Beispiel<br />
voranzugehen.<br />
77<br />
ABSTRACTS | GERMAN<br />
Abstracts | German
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
78<br />
INSIDE NUCLEAR WITH NUCNET<br />
WANO to Increase Focus on New<br />
Nuclear as Industry’s Centre of Gravity<br />
Shifts Towards Asia<br />
NucNet<br />
The World Association of Nuclear Operators (WANO) intends to focus more on new nuclear units coming<br />
into operation around the world as the “centre of gravity” in the industry shifts from the US and Europe to<br />
the Middle East and Asia.<br />
The organisation’s chief executive officer, Peter Prozesky,<br />
told NucNet that new-build projects in China, India, Turkey<br />
and the United Arab Emirates are giving WANO the<br />
opportunity to make sure those countries start the<br />
operational life of their new units “in a very positive way”.<br />
He said the rate of new-build in these new nuclear<br />
markets means there could be challenges, even for existing<br />
companies, related to rapid expansion. There could be<br />
challenges to the ability of some expanding companies<br />
to provide experienced and qualified people to staff their<br />
new units, he said.<br />
In supporting countries with new units beginning<br />
operation, WANO is working more closely with the<br />
International Atomic Energy Agency (IAEA). One of the<br />
IAEA’s tasks is to help emerging nuclear countries develop<br />
the infrastructure and capability they need to have nuclear<br />
power as part of their energy mix.<br />
Mr Prozesky said WANO, whose members operate some<br />
440 nuclear reactor units in more than 30 countries, has<br />
developed a strong relationship between its London office<br />
and IAEA headquarters in Vienna to ensure that experience<br />
is regularly shared. He said: “The IAEA gets involved with<br />
new entrants a lot earlier than we do. They are focusing on<br />
member countries and setting up infrastructure, while<br />
WANO needs to engage when new-build contracts get<br />
signed. The aim is now to have WANO involved as early as<br />
possible.”<br />
WANO is developing training modules and support<br />
missions for new nuclear countries. Modules cover the<br />
period from the start of contractual work to commercial<br />
operation, and aim to help utilities and companies during<br />
the construction and commissioning phases. Early engagement<br />
with the IAEA is part of WANO’s Compass plan, which<br />
was conceived in 2015 and updated at this year’s biennial<br />
general meeting, in Gyeongju, South Korea.<br />
The revised schedule for Compass, which also includes<br />
plans to make WANO more effective in areas such as<br />
life-extensions and decommissioning of plants, is 2<strong>02</strong>2.<br />
The original Compass ran until 2019, but that target has<br />
now been revised, Mr Prozesky said.<br />
Earlier this year the IAEA and WANO agreed to increase<br />
their cooperation to strengthen operational safety and to<br />
support countries that are planning or considering<br />
launching nuclear power programmes. They said they<br />
can maximise safety benefits, increase efficiency and<br />
avoid conflicting advice by increasing cooperation on<br />
safety peer review services.<br />
Increasing the efficiency of the reviews will be particularly<br />
important in anticipation of the increasing number of<br />
nuclear facilities worldwide in coming decades, WANO<br />
chairman Jacques Regaldo said at the time. “By 2030, half<br />
of the nuclear power reactors will be based in Asia, and we<br />
will have many newcomers to nuclear power,” he said.<br />
“There is real value for WANO to work together with the<br />
IAEA and others to help maximise the safety and reliability<br />
of nuclear power plants.”<br />
In an August 2017 report the IAEA said it foresees a<br />
significant decline in nuclear expansion in North America<br />
and in northern, western and southern Europe, with only<br />
slight increases in Africa and western Asia.<br />
But significant growth is projected in central and<br />
eastern Asia, where nuclear power capacity is expected to<br />
undergo an increase of 43 % by 2050.<br />
WANO has been discussing plans for a new regional<br />
centre in Asia to meet demand for expertise and missions<br />
from companies operating new units. The organisation<br />
already has regional centres in Atlanta, Moscow, Paris and<br />
Tokyo, with a head office in London.<br />
WANO has decided to look into the possibility of setting<br />
up a new regional centre, starting with a proposal to open<br />
a branch of the London office in Shanghai. The main aim of<br />
this office will be to develop local expertise.<br />
The second phase of opening a new regional centre<br />
would then include converting the branch office into a<br />
support centre which would provide support services to<br />
other regions. These initial preparations depend on a vote<br />
by WANO members, probably in <strong>2018</strong>. When the support<br />
centre is operating as it should, it would become a fully<br />
operational regional centre.<br />
Mr Prozesky said WANO is holding discussions with<br />
its Chinese members about “the sharing of financial<br />
responsibility” for funding the Shanghai office through the<br />
first two phases.<br />
At its biennial general meeting, WANO discussed the<br />
implications of financial and market pressures. Corporate<br />
organisations “have huge responsibilities” to ensure that<br />
operating nuclear plants are carefully managed and<br />
adequately resourced in these difficult times, Mr Prozesky<br />
said.<br />
The organisation also started a discussion on how it<br />
should be supporting units when they approach the end of<br />
their designed lifetime.<br />
Members spoke about the need to increase cooperation<br />
amongst like-minded organisations such as the IAEA and<br />
the Paris-based Nuclear Energy Agency.<br />
WANO recently announced the signing of a cooperation<br />
agreement with the International Youth Nuclear Congress<br />
(IYNC), recognition of the fact that WANO needs to find<br />
ways to transfer knowledge from people who have been in<br />
the industry for the past 40 years to those who are entering<br />
it today.<br />
Mr Prozesky said it was “quite sobering” to talk to young<br />
operators in control rooms today and find that some of<br />
them weren’t born when the Chernobyl accident happened<br />
in 1986. He said: “It is essential that transfer all the<br />
accumulated knowledge and the industry’s experience to<br />
Inside Nuclear with NucNet<br />
WANO to Increase Focus on New Nuclear as Industry’s Centre of Gravity Shifts Towards Asia ı NucNet
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
the new generation. We must find out how to make the<br />
industry attractive to the younger generation.”<br />
Mr Prozesky said members have asked WANO “to do a<br />
little bit more” on providing support as opposed to just<br />
carrying out assessments of their businesses. He said<br />
another point in the updated Compass document is<br />
associated with putting more energy into leadership<br />
development. “We find in our assessment process across<br />
the world, when looking at corporate organisations and<br />
power plants, that there is a need for WANO to develop<br />
products and services aimed at creating leaders for the<br />
nuclear industry.<br />
“So, we will be putting some energy into that over the<br />
next four years. Particularly again, the focus and emphasis<br />
will be on new entrants and new units, but there is an<br />
overall need for developing leadership in the rest of the<br />
world as well.”<br />
Author<br />
NucNet<br />
The Independent Global Nuclear News Agency<br />
Editor responsible for this story: Kamen Kraev<br />
Avenue des Arts 56<br />
1000 Brussels, Belgium<br />
www.nucnet.org<br />
DATF EDITORIAL NOTES<br />
79<br />
Notes<br />
New Explanatory Video: Multi-Talented Nuclear Technology<br />
Nuclear technology is an everyday, important and sometimes<br />
indispensable part of our modern life – even where it is hardly<br />
recognized as such.<br />
Our explanatory video presents various applications and<br />
shows by the examples of medicine and industry, why nuclear<br />
technology not only enriches our life but also can make it safer,<br />
healthier and longer.<br />
You get brief informations on these and more topics in this<br />
explanatory video from DAtF (in German).<br />
3 The complete video can be watched at www.kernenergie.de<br />
or at the DAtF YouTube channel.<br />
3 A more comprehensive brochure of DAtF on nuclear technology<br />
and additional information (all in German) are available on<br />
www.kernenergie.de.<br />
For further details<br />
please contact:<br />
Nicolas Wendler<br />
DAtF<br />
Robert-Koch-Platz 4<br />
10115 Berlin<br />
Germany<br />
E-mail: presse@<br />
kernenergie.de<br />
www.kernenergie.de<br />
DAtF Notes
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
80<br />
CALENDAR<br />
Calendar<br />
<strong>2018</strong><br />
05.<strong>02</strong>.-07.<strong>02</strong>.<strong>2018</strong><br />
Components and Structures under Severe<br />
Accident Loading Cossal (COSSAL).<br />
Cologne, Germany. OECD/NEA, GRS,<br />
www.grs.de, www.oecd-nea-org<br />
07.<strong>02</strong>.-08.<strong>02</strong>.<strong>2018</strong><br />
8. Symposium Stilllegung und Abbau<br />
kerntechnischer Anlagen. Hanover, Germany.<br />
TÜV Nord, www.tuev.nord.de<br />
26.<strong>02</strong>.-01.03.<strong>2018</strong><br />
Nuclear and Emerging Technologies for Space<br />
<strong>2018</strong>. Las Vegas, NV, USA. American Nuclear Society<br />
(ANS), www.ans.org<br />
01.03.<strong>2018</strong><br />
7. Fachgespräch Endlagerbergbau. Essen,<br />
Germany, DMT, GNS, www.dmt-goup.com<br />
04.03.-09.03.<strong>2018</strong><br />
82. Jahrestagung der DPG. Erlangen, Germany,<br />
Deutsche Physikalische Gesellschaft (DPG),<br />
www.dpg-physik.de<br />
11.03.-17.03.<strong>2018</strong><br />
International Youth Nuclear Congress (IYNC).<br />
Bariloche, Argentina, IYNC and WiN Global,<br />
www.iync.org/category/iync<strong>2018</strong>/<br />
26.03.-27.03.<strong>2018</strong><br />
Fusion energy using tokamaks: can development<br />
be accelerated? London, United Kingdom,<br />
The Royal Society, royalsociety.org<br />
08.04.-11.04.<strong>2018</strong><br />
International Congress on Advances in Nuclear<br />
Power Plants – ICAPP 18. Charlotte, NC, USA,<br />
American Nuclear Society (ANS), www.ans.org<br />
08.04.-13.04.<strong>2018</strong><br />
11 th International Conference on Methods and<br />
Applications of Radioanalytical Chemistry –<br />
MARC XI. Kailua-Kona, HI, USA, American Nuclear<br />
Society (ANS), www.ans.org<br />
17.04.-19.04.<strong>2018</strong><br />
World Nuclear Fuel Cycle <strong>2018</strong>. Madrid, Spain,<br />
World Nuclear Association (WNA),<br />
www.world-nuclear.org<br />
18.04.-19.04.<strong>2018</strong><br />
9. Symposium zur Endlagerung radioaktiver Abfälle.<br />
Vorbereitung auf KONRAD – Wege zum G2-<br />
Gebinde. Hanover, Germany, TÜV NORD Akademie,<br />
www.tuev-nord.de/tk-era<br />
22.04.-26.04.<strong>2018</strong><br />
Reactor Physics Paving the Way Towards More<br />
Efficient Systems – PHYSOR <strong>2018</strong>. Cancun, Mexico,<br />
www.physor<strong>2018</strong>.mx<br />
08.05.-10.05.<strong>2018</strong><br />
29 th Conference of the Nuclear Societies in Israel.<br />
Herzliya, Israel. Israel Nuclear Society and Israel<br />
Society for Radiation Protection, ins-conference.com<br />
13.05.-19.05.<strong>2018</strong><br />
BEPU-<strong>2018</strong> – ANS International Conference on<br />
Best-Estimate Plus Uncertainties Methods. Lucca,<br />
Italy, NINE – Nuclear and INdustrial Engineering S.r.l.,<br />
ANS, IAEA, NEA, www.nineeng.com/bepu/<br />
13.05.-18.05.<strong>2018</strong><br />
RadChem <strong>2018</strong> – 18 th Radiochemical Conference.<br />
Marianske Lazne, Czech Republic,<br />
www.radchem.cz<br />
14.05.-16.05.<strong>2018</strong><br />
ATOMEXPO <strong>2018</strong>. Sochi, Russia,<br />
atomexpo.ru<br />
15.05.-17.05.<strong>2018</strong><br />
11 th International Conference on the Transport,<br />
Storage, and Disposal of Radioactive Materials.<br />
London, United Kingdom, Nuclear Institute,<br />
www.nuclearinst.com<br />
20.05.-23.05.<strong>2018</strong><br />
5 th Asian and Oceanic IRPA Regional Congress on<br />
Radiation Protection – AOCRP5. Melbourne,<br />
Australia, Australian Radiation Protection Society<br />
(ARPS) and International Radiation Protection<br />
Association (IRPA), www.aocrp-5.org<br />
29.05.-30.05.<strong>2018</strong><br />
49 th Annual Meeting on Nuclear Technology<br />
AMNT <strong>2018</strong> | 49. Jahrestagung Kerntechnik.<br />
Berlin, Germany, DAtF and KTG,<br />
www.nucleartech-meeting.com<br />
03.06.-07.06.<strong>2018</strong><br />
38 th CNS Annual Conference and 42 nd CNS-CNA<br />
Student Conference. Saskotoon, SK, Canada,<br />
Candian Nuclear Society CNS, www.cns-snc.ca<br />
03.06.-06.06.<strong>2018</strong><br />
HND<strong>2018</strong> 12 th International Conference of the<br />
Croatian Nuclear Society. Zadar, Croatia, Croatian<br />
Nuclear Society, www.nuklearno-drustvo.hr<br />
04.06.-07.06.<strong>2018</strong><br />
10 th Symposium on CBRNE Threats. Rovaniemi,<br />
Finland, Finnish Nuclear Society, ats-fns.fi<br />
04.06.-08.06.<strong>2018</strong><br />
5 th European IRPA Congress – Encouraging<br />
Sustainability in Radiation Protection.<br />
The Hague, The Netherlands, Dutch Society for<br />
Radiation Protection (NVS), local organiser,<br />
irpa<strong>2018</strong>europe.com<br />
06.06.-08.06.<strong>2018</strong><br />
2 nd Workshop on Safety of Extended Dry Storage<br />
of Spent Nuclear Fuel. Garching near Munich,<br />
German, GRS, www.grs.de<br />
17.06.-21.06.<strong>2018</strong><br />
ANS Annual Meeting “Future of Nuclear in the<br />
Shifting Energy Landscape: Safety, Sustainability,<br />
and Flexibility”. Philadelphia, PA, USA, American<br />
Nuclear Society (ANS), www.ans.org<br />
25.06.-26.06.<strong>2018</strong><br />
index<strong>2018</strong> – International Nuclear Digital<br />
Experience. Paris, France, Société Française<br />
d’Energie Nucléaire,<br />
www.sfen.org, www.sfen-index<strong>2018</strong>.org<br />
27.06.-29.06.<strong>2018</strong><br />
EEM – <strong>2018</strong> 15 th International Conference<br />
on the European Energy Market. Lodz, Poland,<br />
Lodz University of Technology, Institute of Electrical<br />
Power Engineering, Association of Polish Electrical<br />
Engineers (SEP), www.eem18.eu<br />
29.07.-<strong>02</strong>.08.<strong>2018</strong><br />
International Nuclear Physics Conference 2019.<br />
Glasgow, United Kingdom, www.iop.org<br />
05.08.-08.08.<strong>2018</strong><br />
Utility Working Conference and Vendor<br />
Technology Expo. Amelia Island, FL, USA,<br />
American Nuclear Society (ANS), www.ans.org<br />
22.08.-31.08.<strong>2018</strong><br />
Frédéric Joliot/Otto Hahn (FJOH) Summer School<br />
FJOH-<strong>2018</strong> – Maximizing the Benefits of<br />
Experiments for the Simulation, Design and<br />
Analysis of Reactors. Aix-en-Provence, France,<br />
Nuclear Energy Division of Commissariat à l’énergie<br />
atomique et aux énergies alternatives (CEA) and<br />
Karlsruher Institut für Technologie (KIT),<br />
www.fjohss.eu<br />
28.08.-31.08.<strong>2018</strong><br />
TINCE <strong>2018</strong> – Technological Innovations in<br />
Nuclear Civil Engineering. Paris Saclay, France,<br />
Société Française d’Energie Nucléaire,<br />
www.sfen.org, www.sfen-tince<strong>2018</strong>.org<br />
05.09.-07.09.<strong>2018</strong><br />
World Nuclear Association Symposium <strong>2018</strong>.<br />
London, United Kingdom, World Nuclear Association<br />
(WNA), www.world-nuclear.org<br />
09.09.-14.09.<strong>2018</strong><br />
21 st International Conference on Water<br />
Chemistry in Nuclear Reactor Systems.<br />
EPRI – Electric Power Research Institute,<br />
San Francisco, CA, USA, www.epri.com<br />
09.09.-14.09.<strong>2018</strong><br />
Plutonium Futures – The Science <strong>2018</strong>. San Diego,<br />
United States, American Nuclear Society (ANS),<br />
www.ans.org<br />
10.09.-13.09.<strong>2018</strong><br />
Nuclear Energy in New Europe – NENE <strong>2018</strong>.<br />
Portoroz, Slovenia, Nuclear Society of Slovenia,<br />
www.nss.si/nene<strong>2018</strong>/<br />
17.09.-21.09.<strong>2018</strong><br />
62 nd IAEA General Conference. Vienna, Austria.<br />
International Atomic Energy Agency (IAEA),<br />
www.iaea.org<br />
17.09.-20.09.<strong>2018</strong><br />
FONTEVRAUD 9. Avignon, France,<br />
Société Française d’Energie Nucléaire (SFEN),<br />
www.sfen-fontevraud9.org<br />
17.09.-19.09.<strong>2018</strong><br />
4 th International Conference on Physics and<br />
Technology of Reactors and Applications –<br />
PHYTRA4. Marrakech, Morocco, Moroccan<br />
Association for Nuclear Engineering and Reactor<br />
Technology (GMTR), National Center for Energy,<br />
Sciences and Nuclear Techniques (CNESTEN) and<br />
Moroccan Agency for Nuclear and Radiological<br />
Safety and Security (AMSSNuR), phytra4.gmtr.ma<br />
30.09.-04.10.<strong>2018</strong><br />
TopFuel <strong>2018</strong>. Prague, Czwech Republic,<br />
European Nuclear Society (ENS), American Nuclear<br />
Society (ANS). Atomic Energy Society of Japan,<br />
Chinese Nuclear Society and Korean Nuclear Society,<br />
www.euronuclear.org<br />
30.09.-05.10.<strong>2018</strong><br />
Pacific Nuclear Basin Conferences – PBNC <strong>2018</strong>.<br />
San Francisco, CA, USA, American Nuclear Society<br />
(ANS), www.ans.org<br />
<strong>02</strong>.10.-04.10.<strong>2018</strong><br />
7 th EU Nuclear Power Plant Simulation ENPPS<br />
Forum. Birmingham, United Kingdom, Nuclear<br />
Training & Simulation Group, www.enpps.tech<br />
14.10.-18.10.<strong>2018</strong><br />
12 th International Topical Meeting on Nuclear<br />
Reactor Thermal-Hydraulics, Operation and<br />
Safety – NUTHOS-12. Qingdao, China, Elsevier,<br />
www.nuthos-12.org<br />
14.10.-18.10.<strong>2018</strong><br />
NuMat <strong>2018</strong>. Seattle, United States,<br />
www.elsevier.com<br />
16.10.-17.10.<strong>2018</strong><br />
4 th GIF Symposium at the 8 th edition of Atoms for<br />
the Future. Paris, France, www.gen-4.org<br />
22.10.-24.10.<strong>2018</strong><br />
DEM <strong>2018</strong> Dismantling Challenges: Industrial<br />
Reality, Prospects and Feedback Experience. Paris<br />
Saclay, France, Société Française d’Energie Nucléaire,<br />
www.sfen.org, www.sfen-dem<strong>2018</strong>.org<br />
22.10.-26.10.<strong>2018</strong><br />
NUWCEM <strong>2018</strong> Cement-based Materials for<br />
Nuclear Waste. Avignon, France, French<br />
Commission for Atomic and Alternative Energies<br />
and Société Française d’Energie Nucléaire,<br />
www.sfen-nuwcem<strong>2018</strong>.org<br />
24.10.-25.10.<strong>2018</strong><br />
Chemistry in Power Plant. Magdeburg, Germany,<br />
VGB PowerTech e.V., www.vgb.org<br />
11.11.-15.11.<strong>2018</strong><br />
ANS Winter Meeting. Orlando, FL, USA,<br />
American Nuclear Society (ANS), www.ans.org<br />
Calendar
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
Development of High Temperature<br />
Gas Cooled Reactor in China<br />
Wentao Guo and Michael Schorer<br />
1 Introduction of HTGR Recent developments in High Temperature Gas Cooled Reactor (HTGR) attracted<br />
widespread attention. China, Japan, South Africa, USA, Russia and France are all actively initiating the development<br />
work of HTGR. Some developing countries expressed great interest in this type of reactor [1].<br />
| | Fig. 1.<br />
The 10 MWt High Temperature<br />
Gas-cooled Reactor (HTGR)<br />
| | Fig. 2.<br />
The Pebble fuel element<br />
of the HTGR<br />
HTGR is one of the six Generation IV reactors put forward<br />
by Generation IV International Forum (GIF) in 20<strong>02</strong>.<br />
This type of reactor has high outlet temperature. It uses<br />
Helium as coolant and graphite as moderator. The helium<br />
temperature at the reactor core inlet/outlet is 250/750 °C.<br />
Pebble fuel and ceramic reactor core are adopted. At the<br />
center of each poppy seed-size fuel particle is a uranium<br />
kernel. Layers of carbon and silicon carbide contain the<br />
radioactive material [2]. Figure 1 shows the overall<br />
structure of the HTR-10 MW Test Module constructed by<br />
Institute of Nuclear and New Energy Technology, Tsinghua<br />
University (INET). Figure 2 shows the pebble fuel element<br />
structure of HTGR.<br />
The most important feature of modular high temperature<br />
gas cooled reactor is that under any accident conditions,<br />
including large loss of coolant accident (LLOCA),<br />
the reactor can keep in safe state without any human or<br />
machine intervention.<br />
Modular HTGR also has other advantages such as:<br />
1. High generating efficiency: Its efficiency is 25 % higher<br />
than pressurized water reactor (PWR) nuclear power<br />
plants because of the high outlet temperature.<br />
2. 2. Short construction period: 100 MWe HTGR adopts<br />
modular construction approach. Construction period<br />
can be reduced to two years. Compared to PWR power<br />
plants which have 5 to 6 years of construction, the<br />
interest payment during construction is reduced and<br />
the construction investment can be reduced by 20 %.<br />
3. 3. Simple system: The HTGR has passive safety features<br />
which greatly simplify the system. Engineering safety<br />
facilities like emergency core cooling system and full<br />
grade containment don’t need to be installed, which<br />
can reduce the construction investment.<br />
2 The development history of China’s HTR<br />
and its current situation<br />
The HTGR research and development work in China started<br />
in 1970s. By implementing the National High-Technology<br />
Project (863), Tsinghua University designed and<br />
built HTR-10 MW Test Module under the support<br />
of China National Nuclear Corporation (CNNC). It<br />
realized the first power generation on January 7,<br />
2003 [3].<br />
In 2006, Tsinghua University in Beijing, China<br />
Nuclear Engineering Group Corporation (CNEC)<br />
and China Huaneng Group co-financed the<br />
construction of the HTR demonstration project,<br />
after which a complete industrial chain is formed.<br />
In this system, Institute of Nuclear and New Energy<br />
Technology, Tsinghua University is the liability<br />
subject of R&D in charge of technology R&D,<br />
providing design and technical support; CNEC<br />
is the major special project implementation<br />
body, responsible for designing, purchasing and<br />
constructing the demonstration project of<br />
nuclear island and its auxiliary system; Huaneng Shandong<br />
Shidao Bay Nuclear Power CO., LTD. takes charge of the<br />
investment operations of the demonstration project [4].<br />
The High Temperature Reactor-Pebble-bed Modules<br />
(HTR-PM) under construction has two reactors and<br />
one turbine. On December 9, 2012, the construction of<br />
Shandong Rongcheng Shidao Bay HTR demonstration<br />
project started. On April 20, 2015, civil construction of the<br />
basements came to an end and turned to the intensive<br />
equipment installation stage. The key point for construction<br />
was shifted from civil construction to installation<br />
construction. On June the 24 th , after two months of<br />
arduous struggle, the Shidao Bay Nuclear Power Project<br />
completed the pouring task of the reactor building<br />
walls for the first modular High Temperature Gas-cooled<br />
Demonstration Reactor in the world [5]. The reactor<br />
building walls were poured to 41.30 meters, marking<br />
the HTGR project meeting the requirement of heavy<br />
equipment lifting. On June the 27 th , capping of the Shidao<br />
Bay HTGR conventional island is finished [6]. This is<br />
another major project after the pouring task on June 24 th .<br />
On March 3, 2016, the construction of the reactor<br />
pressure vessel (RPV) and metal components inside the<br />
reactor was finished and they were transported to the site.<br />
On September 14, 2016, they finished installing the RPV<br />
for the first and second reactor as well as the internal metal<br />
components of RPV for the first reactor. The cylindrical<br />
vessel, 25 meters high and weighing 610 tons, is the<br />
biggest, heaviest and most complicated pressure vessel for<br />
a nuclear reactor, according to a statement from Huaneng<br />
Shandong Shidao Bay Nuclear Power Co. (HSNPC), the<br />
plant’s builder and operator. On October 14, 2016, the<br />
demonstration project finished all the tests of inverse<br />
power transmission successfully. On December 29, 2016,<br />
the main control room in Shidao Bay nuclear power plant<br />
is ready to be used. On January 21, 2017, the installation of<br />
the reactor core vessel was finished. The reactor core vessel<br />
is the key component of the metal structures inside the<br />
81<br />
ENERGY POLICY, ECONOMY AND LAW<br />
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Development of High Temperature Gas Cooled Reactor in China ı Wentao Guo and Michael Schorer
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
ENERGY POLICY, ECONOMY AND LAW 82<br />
reactor core. It is used to support the reactor core and<br />
locate the reactor core components. On June 8, 2017, the<br />
installation of the ceramic components inside the second<br />
reactor core was finished, which means half of the<br />
installation progress of the main facilities in the nuclear<br />
island has been done. Before August 11, 2017, the fuel<br />
production line has produced 250,000 pebbles, which met<br />
the requirement of connecting to the grid for HTR-PM.<br />
The project is planned to be completed and put into operation<br />
at the end of 2017/beginning of <strong>2018</strong>, but probably<br />
it will be delayed (Figure 3). The design lifetime of<br />
HTR-PM is 40 years.<br />
| | Fig. 3.<br />
The construction of Shidao Bay HTGR conventional island was finished<br />
on June 27, 2015 (photo credits: Shidao Bay NPP).<br />
3 Safety features of HTGR<br />
One of the most important safety issues for nuclear power<br />
plant is decay heat removal. In the Three Mile Island and<br />
Fukushima Daiichi nuclear accidents, the reactor cores are<br />
overheated and melt down due to the failure of decay heat<br />
removal. In Chernobyl accident, the failure of decay heat<br />
removal system caused the resulting sequences after the<br />
initial exploration due to the fission power increment.<br />
So developing a highly reliable emergency core cooling<br />
system with reliable water and electricity supply is very<br />
important for a light water reactor (LWR).<br />
But for HTGR, inherent safety can be achieved based<br />
on three physical ideas: 1. using silicon carbide (SiC),<br />
which has very good heat-resistance, as the fuel cladding;<br />
2. lowering the volumetric power density of the reactor<br />
core significantly; 3. using identical small reactor modules<br />
to replace a large reactor in order to make sure that the<br />
reactor core won’t be heated to the temperature limit [7].<br />
Besides physical ideas, the safety of HTGR can be<br />
protected from three engineering designs:<br />
1. Multiple barriers to prevent the release of<br />
radioactivity<br />
The HTGR has three safety barriers to prevent the release<br />
of radioactivity. The first barrier is the fuel particles coated<br />
with SiC. The maximum temperature of the fuel particles<br />
is designed to be limited to 1,600 °C under any operation<br />
or accident conditions. Less than 1,600 °C, the coat of the<br />
particles can maintain integrated [8]. The second barrier<br />
is the pressure boundary of the primary circuit, which<br />
contains the reactor pressure vessel, the steam generator<br />
pressure vessel and the hot gas duct pressure vessel which<br />
connects the previous two vessels. The likelihood for<br />
these three vessels to have ruptures can be neglected. The<br />
third barrier is the bounding volume, which contains the<br />
primary circuit cabin, Helium purification cabin as well as<br />
fuel loading and unloading cabin. They can prevent the<br />
radioactive gas to be released into the atmosphere.<br />
2 Passive decay heat removal system<br />
The thermal design of HTGR has already considered that<br />
in case of any accidents, the cooling of the reactor core<br />
doesn’t need any active decay heat removal system. The<br />
decay heat in the reactor core can be removed from the<br />
core to the surface cooler outside of the reactor pressure<br />
vessel passively through heat conduction and radiation.<br />
Then the heat can be passed to the atmosphere from the<br />
surface cooler by nature convection. If the primary circuit<br />
lost pressure and the main and the auxiliary decay heat<br />
removal system are out of work, the decay heat can still be<br />
removed from the core to the outside. The reactor core<br />
meltdown can be avoided. Under accident conditions,<br />
because the decay heat cannot be removed by the main<br />
decay heat removal system, the temperature of the pebbles<br />
will be increased. In order to make sure the maximum<br />
temperature of the pebbles will not exceed 1,600 °C, some<br />
restrictions to the power density and geometry of the<br />
reactor core are necessary. That’s the reason why the<br />
capacity of the HTGR is usually small.<br />
3 Negative temperature coefficient has good reactivity<br />
compensation<br />
The reactor has a relatively high negative temperature<br />
coefficient for the fuel and moderator and if it is under<br />
normal condition, the margin between the maximum<br />
temperature of the pebbles and its limit is large. The<br />
negative temperature coefficient can give a good reactivity<br />
compensation. When a positive reactivity is introduced<br />
into the reactor, it can be automatically shut down thanks<br />
to the reactivity compensation from the negative temperature<br />
coefficient [9].<br />
The long term operation of HTR-10 and different<br />
safety experiments have proved the inherent safety of<br />
HTGR, which improved the public acceptance of nuclear<br />
reactors.<br />
4 Fuel technology<br />
In 2005, INET built a prototyping fuel-production facility<br />
with a capacity of 100,000 fuel elements per year. In order<br />
to solidify the fabrication level, INET started to construct<br />
HTGR fuel-production factory in Baotou, Northern China<br />
in 2013. The fuel-production equipment was installed in<br />
2014. In 2015, they started the commissioning and trial<br />
production. Some experiments have been done in Petten,<br />
the Netherlands. The irradiation test of five fuel spheres of<br />
the HTR-PM started in October 2012 in the high flux<br />
reactor (HFR) and finished on December 30, 2014. The<br />
fuel sphere quality, which is one of the key technologies in<br />
HTR-PM project, has been proved to meet the requirements<br />
[7].<br />
On August 15, 2016, the construction of the fuel<br />
production line in Baotou was finished and the fuel pebble<br />
production started. By July 17, 2017, the fuel production<br />
line has already produced 200,000 pebbles. It means<br />
that the fuel production of HTGR has shifted from trial<br />
production to industrial production. It also means that the<br />
fuel production technology of HTGR in China is leading<br />
the world, which has great significance for achieving<br />
commercialization and export of HTGR [10].<br />
When a fuel element is discharged from the bottom<br />
of the RPV to the fuel handling system, its burn-up is<br />
measured immediately. If its burn-up does not reach the<br />
design burn-up limit, it will be recharged into the reactor<br />
Energy Policy, Economy and Law<br />
Development of High Temperature Gas Cooled Reactor in China ı Wentao Guo and Michael Schorer
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
core from the top of the RPV. Otherwise it will be identified<br />
as a spent fuel and sent to the spent fuel storage system. In<br />
the spent fuel storage system, spent fuels are put into a<br />
storage canister. Each storage canister contains 40,000<br />
spent fuels. After a storage canister is full with spent<br />
fuels, it is sealed and moved to the ventilated storage well.<br />
Each storage well contains five vertically placed storage<br />
canisters. Spent fuels after ten years of storage will be<br />
moved from the nuclear island to a large intermediate<br />
storage building on the site and stored there during the<br />
rest service time of the plant. As for reprocessing, it is<br />
technically feasible and similar to the technology used in<br />
PWR. At present, China is still developing this reprocessing<br />
technology and tends to apply it in the future.<br />
5 Future expectations of HTGR in China<br />
The HTGR industrialization has shifted from research<br />
toward commercial applications. CNEC announced that<br />
the feasibility study report of the 600 MWe commercial<br />
high temperature reactor project in Ruijin, Jiangxi province<br />
has passed the experts auditing and promises to be the<br />
first commercial Generation IV nuclear power plant in the<br />
world. At present, China has mastered all the technology of<br />
HTGR systematically and takes the lead in the world.<br />
The home manufacture can be realized for 95 % of the<br />
equipment.<br />
Next step, CNEC and Jiangxi Province will combine<br />
together and submit the project proposals to the National<br />
Development and Reform Commission (NDRC), applying to<br />
list the project into National Nuclear Long-and-medium<br />
Term Development Planning. After having the permit, the<br />
feasibility study of the project will be carried out. Land<br />
requisition, “Five-outlet-one Dish” 1<br />
and construction of<br />
auxiliary facilities will be carried on at the same time. After<br />
getting the approval from NDRC and obtaining building<br />
permits from National Nuclear Safety Administration<br />
( NNSA), the commencement of work for the two units in<br />
the first-stage project was planned in 2017 and they would<br />
be combined to the grid around 2<strong>02</strong>1. But due to some<br />
reasons this project is delayed and hasn’t been started yet.<br />
6 HTGR cooperation between China and<br />
other countries<br />
By the way of multi-module combination, the installed<br />
capacity of HTGR nuclear power units can be 200 MWe,<br />
400 MWe, 600 MWe, 800 MWe and 1000 MWe, which can<br />
be operated with flexibility to suit the market and meet<br />
the need of different power grid. It is suitable for being<br />
constructed close to load centers as well as in countries<br />
and regions with small or middle power grids.<br />
Many countries in Southeast Asia, Middle East and<br />
Europe, including some potential users in China, express a<br />
keen interest in the application of HTGR in nuclear electric<br />
power generation, sea water desalination, petrochemical<br />
industry and coal chemical industry. The related business<br />
cooperation is under way.<br />
At present, CNEC starts working on HTGR preliminary<br />
work in Jiangxi, Hunan, Guangdong, Fujian, Shandong,<br />
Hubei and Zhejiang province successively. Meanwhile,<br />
CNEC signs the memorandum of understanding (MOU) on<br />
cooperation with Dubai Nuclear Energy Committee and<br />
provides King Abdulaziz City for Science and Technology<br />
(KACST) with the design scheme of HTGR sea water desalination.<br />
They have also reached a consensus on signing the<br />
memorandum of understanding on cooperation with Saudi<br />
Energy City. On April 21, 2015, they signed the MOU<br />
with South African Nuclear Energy Corporation (NECSA).<br />
CNEC is jointly with other organization concerned to provide<br />
nuclear fuels, spent fuel reclamation, nuclear power<br />
plant operation, technical support, personnel training and<br />
other integration services to the international market.<br />
7 Conclusions<br />
The Generation IV nuclear power system is an advanced<br />
system which has a major revolution in economy, safety,<br />
waste treatment and nuclear nonproliferation. HTGR is<br />
considered to be the most possibly actualized and the most<br />
promising advanced reactor type in the near future by the<br />
international nuclear community [9].<br />
Under the support of the National High-Technology<br />
Project, Institute of Nuclear and New Energy Technology,<br />
Tsinghua University constructed the HTR-10 MW Test<br />
Module successfully, and achieved joining the national<br />
power grid with full power. Long-term operation and<br />
safety tests verified the intrinsic safety of HTGR and<br />
proved the technical feasibility of HTGR. The success of<br />
HTR-10 MW Test Module construction and operation<br />
marks that China has made a breakthrough in the R&D of<br />
HTGR. China has been included among those advanced<br />
countries in the development of HTGR technology. The<br />
construction of the Shidao Bay HTR-PM demonstration<br />
project is close to an end. Hopefully it will start operation<br />
in the near future. At that time, it will be the world’s first<br />
modular HTGR commercial demonstration power plant.<br />
In early 2006, large pressurized water reactor and<br />
HTGR were included in the 16 major scientific and<br />
technological projects by “China’s national policy for<br />
medium and long-term scientific development” in which<br />
they are striving to make breakthroughs in 15 years.<br />
Actualizing the major scientific and technological project<br />
of HTGR marks that the HTGR technology in which China<br />
has self-owned intellectual property takes a crucial step<br />
towards industrialization.<br />
References<br />
[1] Zongxin, Wu: The development of high temperature gas-cooled<br />
reactor in China. Nuclear Power Engineering 21.1 (2000): 39-43.<br />
[2] http://baike.baidu.com/<br />
[3] http://military.china.com/news/568/20150421/19562626.html<br />
[4] http://digitalpaper.stdaily.com/http_www.kjrb.com/kjrb/<br />
html/2014-11/01/content_282325.htm?div=-1<br />
[5] http://www.cet.com.cn/nypd/hn/1576726.shtml<br />
[6] http://paper.people.com.cn/zgnyb/html/2015-07/06/<br />
content_1585012.htm<br />
[7] Zhang, Zuoyi, et al.: The Shandong Shidao Bay 200 MW e High-<br />
Temperature Gas-Cooled Reactor Pebble-Bed Module (HTR-PM)<br />
Demonstration Power Plant: An Engineering and Technological<br />
Innovation. Engineering 2.1 (2016): 112-118.<br />
[8] Tang, Chunhe, et al.: Research and development of fuel element<br />
for Chinese 10 MW high temperature gas-cooled reactor. Journal<br />
of Nuclear Science and Technology 37.9 (2000): 8<strong>02</strong>-806.<br />
[9] Fu Xiaoming, Wangjie, October 2006. Summary of HTGR<br />
Development in China. Modern Electric Power.<br />
[10] http://energy.people.com.cn/n1/2017/0718/<br />
c71661-29412747.html<br />
Authors<br />
Wentao Guo<br />
Paul Scherrer Institute<br />
Department of Nuclear Energy and Safety<br />
5232 Villigen PSI, Switzerland<br />
Michael Schorer<br />
Swiss Nuclear Forum<br />
4600 Olten, Switzerland<br />
1) Five-outlet-one Dish:<br />
In order to construct<br />
rationally and<br />
orderly, some firstphase<br />
preparations<br />
need to be made,<br />
such as electrifying,<br />
communication,<br />
road access, water<br />
access, gas access<br />
and land smoothing.<br />
ENERGY POLICY, ECONOMY AND LAW 83<br />
Energy Policy, Economy and Law<br />
Development of High Temperature Gas Cooled Reactor in China ı Wentao Guo and Michael Schorer
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
Die Haftung nach § 26 AtG – ein Mauerblümchen?<br />
84<br />
SPOTLIGHT ON NUCLEAR LAW<br />
Christian Raetzke<br />
Die Haftung für Schäden aus Radioaktivität kann sich nach deutschem Recht aus drei Quellen ergeben. In der<br />
öffentlichen und juristischen Diskussion ist fast immer nur von der Haftung nach dem Pariser Übereinkommen (PÜ) die<br />
Rede. Das PÜ gilt in Deutschland unmittelbar (siehe auch § 25 AtG – Atomgesetz). Es regelt aber nicht den gesamten<br />
Bereich der Atomhaftung, sondern – grob gesagt – nur die Haftung im Rahmen der Kernenergie; für diesen Bereich<br />
mit „besonderem Gefährdungspotential“ wurde ein internationaler Regelungsbedarf gesehen. Das PÜ gilt für<br />
Kernkraftwerke, im „Front end“ für Anreicherungsanlagen und Brennelementfabriken und im „Back end“ für Aktivitäten<br />
rund um die Abfälle aus Kernkraftwerken, jeweils einschließlich der entsprechenden Beförderungsvorgänge.<br />
Als zweite Rechtsgrundlage regelt § 25a AtG die Haftung<br />
für Reaktorschiffe. Mit der Ausmusterung der Otto Hahn<br />
ist diese Norm aber vor langer Zeit in der Versenkung<br />
verschwunden.<br />
Und dann gibt es schließlich den § 26 AtG. Juristisch ist<br />
die Norm als sog. Auffangtatbestand gestaltet. Sie erfasst<br />
alle Schäden „durch die Wirkung eines Kernspaltungsvorgangs<br />
oder der Strahlen eines radioaktiven Stoffes oder<br />
durch die von einer Anlage zur Erzeugung ionisierender<br />
Strahlen ausgehende Wirkung ionisierender Strahlen“,<br />
die nicht in den Anwendungsbereich des PÜ oder des<br />
§ 25a AtG fallen. Aus dieser Negativdefinition und<br />
gleichsam Subtraktion ergibt sich, dass § 26 vor allem auf<br />
Anlagen und Tätigkeiten außerhalb der Kernenergie (und<br />
außer Reaktorschiffen) Anwendung findet, also hauptsächlich<br />
auf den Umgang mit Radioaktivität im Bereich<br />
der Medizin, Industrie (z. B. Prüfstrahler) und Forschung.<br />
Unter die Haftung nach § 26 fallen aber auch solche<br />
Bereiche der Kernindustrie, die aufgrund ihres geringen<br />
Schadenspotentials vom PÜ ausgeschlossen werden,<br />
insbesondere Aktivitäten rund um Natururan und abgereichertes<br />
Uran. Schließlich ordnet § 26 Abs. 2 AtG eine<br />
entsprechende Geltung für die Kernfusion an.<br />
Die Haftung nach § 26 AtG trifft den Besitzer<br />
radio aktiver Stoffe oder von Anlagen zur Erzeugung<br />
ionisierender Strahlen, weswegen man hier von Besitzerhaftung<br />
spricht (manchmal wird auch der Begriff<br />
Isotopenhaftung verwendet, was aber ungenau ist, da es<br />
eben nicht nur um radioaktive Stoffe geht). Im Falle der<br />
Beförderung radioaktiver Stoffe haftet nach Abs. 6 der<br />
Absender.<br />
Dass § 26 AtG für Aktivitäten gilt, die das PÜ gleichsam<br />
„übrig lässt“ und die mit einem geringeren Gefahrenpotential<br />
assoziiert werden, schmälert keinesfalls die<br />
Bedeutung der Norm. Denn zum einen dürften diese Fälle<br />
des Umgangs mit Radioaktivität zahlenmäßig diejenigen,<br />
die sich aus der Nutzung der Kernenergie ergeben, weit<br />
übersteigen; man denke nur an die vielen Transporte von<br />
Strahlenquellen für Medizin und Industrie, die jeden Tag<br />
stattfinden. Zum anderen können sich auch aus diesen<br />
Anlagen und Tätigkeiten im ungünstigsten Fall zwar kaum<br />
nationale Katastrophen, aber doch erhebliche Schäden<br />
bis hin zum Tod von Personen oder zu komplizierten<br />
Kontaminationen ergeben.<br />
In der Frage, ob die Haftung nach § 26 AtG eine<br />
Verschuldenshaftung wie die allgemeine Haftung des<br />
Bürgerlichen Gesetzbuches (setzt Vorsatz oder Fahrlässigkeit<br />
voraus) oder eine verschuldensunabhängige<br />
Gefährdungshaftung (wie im PÜ) sein sollte, hat der<br />
Gesetzgeber eine mittlere Lösung gewählt, die sog. modifizierte<br />
Gefährdungshaftung. Im Grundsatz ist es eine<br />
Gefährdungshaftung: der Geschädigte muss im Prozess<br />
nicht behaupten und beweisen, dass den Besitzer/ Absender<br />
ein Verschulden trifft. Vielmehr ist es am Besitzer/<br />
Absender, einen Entlastungsbeweis zu führen, wenn er<br />
kann; immerhin hat er – im Gegensatz zur reinen Ge fährdungs<br />
haftung – diese Option. § 26 Abs. 1 Satz 2 AtG gibt<br />
hierfür allerdings qualifizierte (erschwerte) Bedingungen<br />
vor; fehlendes Verschulden reicht nicht, es müssen weitere<br />
Umstände wie etwa die nachweisbare „Anwendung jeder<br />
nach den Umständen gebotenen Sorgfalt“ hinzukommen.<br />
Das ist eine hohe Hürde.<br />
Ein zweiter interessanter Aspekt betrifft die Frage<br />
einer möglichen Kanalisierung. Im PÜ ist die Haftung<br />
bekanntlich ausschließlich auf den Inhaber (Betreiber)<br />
einer Kernanlage konzentriert. Zulieferer, Dienstleister<br />
etc. sind freigestellt; Anspruchsgrundlagen außerhalb des<br />
PÜ werden ausgeschlossen. Für den Bereich des § 26 AtG<br />
hat der Gesetzgeber diese Lösung nicht übernommen.<br />
Dem Geschädigten stehen also neben § 26 AtG auch alle<br />
anderen Anspruchsgrundlagen des Haftungsrechts zur<br />
Verfügung und er kann, wenn die Voraussetzungen<br />
vorliegen, auch andere Beteiligte als den Besitzer/<br />
Absender in Anspruch nehmen. Als „Ausgleich“ für diese<br />
anderen Beteiligten ist in § 4 der Atomrechtlichen<br />
Deckungsvorsorge-Verordnung (AtDeckV) geregelt, dass<br />
der Besitzer/Absender sie in bestimmtem Umfang in seine<br />
eigene Haftpflichtversicherung einbeziehen muss (sog.<br />
wirtschaftliche Kanalisierung).<br />
Damit ist auch schon ein dritter Aspekt angesprochen:<br />
für Tätigkeiten im Bereich des § 26 AtG, die einer<br />
Genehmigung bedürfen, muss im Genehmigungs verfahren<br />
eine Deckungsvorsorge (§ 13 AtG) nachgewiesen werden,<br />
also in der Regel eine Haftpflichtversicherung. Der Betrag<br />
wird auf der Grundlage der AtDeckV im Genehmigungsverfahren<br />
festgesetzt. Die Haftung selber ist unbegrenzt;<br />
übersteigt ein Schaden also den Betrag der Deckungsvorsorge,<br />
muss der Haftende sein Vermögen einsetzen.<br />
§ 26 trifft schließlich einige Sonderregelungen für die<br />
Anwendung von radioaktiven Stoffen oder ionisierender<br />
Strahlen am Menschen in der medizinischen Forschung<br />
(da wird die Haftung verschärft) oder bei der Ausübung<br />
der Heilkunde (dort gilt unter bestimmten Voraussetzungen<br />
statt § 26 die normale Arzthaftung).<br />
Soweit ersichtlich, gab es bisher keine Schadensfälle<br />
im Bereich des § 26, die Anlass zu einschlägiger Rechtsprechung<br />
geboten hätten; das soll auch möglichst<br />
so bleiben. Angesichts des Kernenergieausstiegs, der<br />
juristischen Aufwertung des Strahlenschutzes durch<br />
das neue Strahlenschutzgesetz und der zunehmenden<br />
Bedeutung der Fusionsforschung wird § 26 AtG aber<br />
möglicherweise dennoch etwas aus dem Schatten<br />
des PÜ heraustreten und vielleicht sein unverdientes<br />
„ Mauerblümchendasein“ abstreifen.<br />
Author<br />
Rechtsanwalt Dr. Christian Raetzke<br />
CONLAR Consulting on Nuclear Law and Regulation<br />
Beethovenstr. 19<br />
04107 Leipzig, Germany<br />
Spotlight on Nuclear Law<br />
The Liability According to § 26 of the German Atomic Energy Act – A Wallflower? ı Christian Raetzke
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
Investigation of Conditions Inside the<br />
Reactor Building Annulus of a PWR<br />
Plant of KONVOI Type in Case of Severe<br />
Accidents with Increased Containment<br />
Leakages<br />
Ivan Bakalov and Martin Sonnenkalb<br />
1 Introduction and analysis method The severe accident at Fukushima Daiichi NPP resulted in<br />
severe core damage and significant releases of hydrogen and radioactive materials from primary containment boundary<br />
into or through the reactor buildings of three out of the six reactors (units 1 to 3). Based on analyses of the accident<br />
progression it was realized that accidentally increased leaks from the inertized containment contributed to the<br />
radionuclide and hydrogen release into the reactor building, thus leading to hydrogen explosions, severely damaging<br />
the reactor building constructions.<br />
The Fukushima Daiichi accident triggered<br />
worldwide stress tests and<br />
re-assessments of the NPP plant<br />
safety. In Germany the process<br />
resulted in an improvement and<br />
extension of the existing severe accident<br />
management (SAM) concept<br />
by both additional preventive and<br />
mitigative measures. The main improvements<br />
in the mitigative domain<br />
is a new concept of severe accident<br />
management guidelines (SAMG) with<br />
strategies and procedures intended to<br />
be used by the plant crisis team for<br />
mitigation of the consequences of<br />
severe accidents. The SAMG concept<br />
follows relevant recommendations<br />
of the German Reactor Safety Commission<br />
RSK [1].<br />
Analyses of the hydrogen as well<br />
as aerosol and noble gas behaviour<br />
in case of increased containment<br />
leakages into the reactor building<br />
annulus of a German PWR KONVOI<br />
reference plant under severe accident<br />
conditions have been performed using<br />
the GRS lumped parameter code<br />
COCOSYS. The investigation carriedout<br />
focusses on the assessment of the<br />
efficiency of newly developed SAM<br />
measures as described in the new<br />
SAMG handbook or some measures<br />
proposed in addition for a PWR<br />
reference plant of KONVOI type. The<br />
assessed strategies are related to the<br />
mitigation of challenging conditions<br />
inside the reactor building (RB)<br />
annulus due to design based and<br />
increased containment leakages<br />
during severe accidents.<br />
The analyses are based on previous<br />
GRS investigations of the hydrogen<br />
mitigation concept with passive autocatalytic<br />
recombiners (PAR) inside<br />
the PWR KONVOI containment [2] as<br />
well as the reassessment of the effectiveness<br />
of the filtered containment<br />
venting concept of PWR KONVOI [3].<br />
The main findings contribute to<br />
further improvement of the planned<br />
mitigative SAM measures in case of<br />
enhanced containment leakages into<br />
the reactor building annulus under<br />
severe accident conditions.<br />
1.1 COCOSYS plant model<br />
The COCOSYS nodalisation scheme<br />
of the PWR KONVOI plant with focus<br />
on the RB annulus is presented in<br />
Figure 1. The nodalisation of the<br />
containment and the RB annulus is<br />
developed in such a way that thermal<br />
and gas stratification processes<br />
expected under accident conditions,<br />
local and global convection flows<br />
between the compartments, and longterm<br />
convection processes inside<br />
the containment could be simulated<br />
appropriately. Therefore, a refined<br />
subdivision of the containment compartments<br />
and RB annulus rooms and<br />
free space was chosen. The model<br />
considers all relevant gaseous and<br />
liquid flows through different compartment<br />
connections such as free<br />
openings, fire protection doors, burst<br />
membranes, drainages, etc. For the<br />
purpose of heat and mass transfer<br />
modelling inside the containment<br />
and the RB annulus heat structures<br />
representing the walls, floors, ceilings<br />
and metal internals are introduced<br />
into the model. With all these features<br />
the model adequately represents all<br />
relevant design specific features of the<br />
PWR KONVOI reference plant – both<br />
inside the containment as well as the<br />
RB annulus.<br />
The containment has a total free<br />
volume of 70,000 m 3 . It is subdivided<br />
into four areas which can have<br />
different convection flow regimes<br />
depending on the initial event of a<br />
sequence and the break/discharge<br />
location. The first area represents the<br />
containment compartments, in which<br />
the reactor pressure vessel and the<br />
steam generators are located. The<br />
| | Fig. 1.<br />
COCOSYS nodalisation scheme of the RB annulus and location of containment penetrations through the containment steel shell.<br />
85<br />
ENVIRONMENT AND SAFETY<br />
Environment and Safety<br />
Investigation of Conditions Inside the Reactor Building Annulus of a PWR Plant of KONVOI Type in Case of Severe Accidents with Increased Containment Leakages ı Ivan Bakalov and Martin Sonnenkalb
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
ENVIRONMENT AND SAFETY 86<br />
second and third area comprises the<br />
operating containment compartments<br />
and the containment dome. The<br />
fourth area includes all the compartments<br />
outside the missile protection<br />
cylinder, the periphery of the containment.<br />
The volume of the RB annulus is<br />
subdivided into four areas with a total<br />
volume of 50,000 m 3 . The first area is<br />
the annular gap, located above elevation<br />
21.5 m, which has a total volume<br />
of 14,900 m 3 . This area, in turn, is<br />
divided into six axial levels along the<br />
height of the gap. It is connected to<br />
the lower part of the annular gap<br />
( second area) below elevation 21.5 m<br />
and has a free volume of 4,300 m 3 . In<br />
this area vertical fire protection walls<br />
with metal sheets are located, which<br />
do not allow atmospheric flow in<br />
azimuthal direction. The third area<br />
comprises several separate annulus<br />
rooms located on building floors at<br />
elevation 6 m to 21.5 m. The annulus<br />
rooms at elevation 6 m to 9 m are<br />
separated from the annular gap by<br />
ventilation systems. The connections<br />
between these separate rooms are<br />
provided with fire protection doors<br />
and fire protection flaps, which automatically<br />
close, if the room temperature<br />
exceed ~70° C. The fourth area<br />
represents all annulus rooms below<br />
elevation 6 m with a total volume of<br />
23,100 m 3 . Those rooms have only a<br />
negligible atmosphere exchange with<br />
the annular gap above.<br />
Moreover, the model consists of<br />
all relevant plant systems used during<br />
accidents (e.g. the RB annulus exhaust<br />
air system) or operational systems<br />
foreseen as SAM measures in the<br />
SAMG handbook (e.g. the annulus<br />
air supply/suction system and the<br />
annulus air recirculation systems).<br />
The filtered containment venting<br />
system and the hydrogen recombination<br />
system with about 65 PARs<br />
installed inside the containment are<br />
introduced in the input deck as well,<br />
using the modelling capabilities of the<br />
engineered safety features, integrated<br />
in the COCOSYS code.<br />
The COCOSYS model also includes<br />
the containment design leakage of<br />
0.25 vol.-%/d into the RB annulus.<br />
For the base case analyses the design<br />
leakage is assumed to be at the most<br />
unfavorable place in the area of the<br />
cable penetrations at elevation 12 m<br />
(Figure 1 right side), e.g. the leakage<br />
is located opposite to the single<br />
suction point of the RB annulus<br />
exhaust air system, operated in case<br />
of an accident. In addition, leakages<br />
are defined from the environment<br />
through the auxiliary building main<br />
gate into the lower annulus rooms<br />
(leakages represented by red arrows<br />
in Figure 1).<br />
1.2 Selected representative<br />
Severe Accident Scenarios<br />
Two representative and different<br />
severe accident scenarios – the base<br />
cases – have been selected for the<br />
analyses. Some characteristics of the<br />
scenarios are summarized here, the<br />
timing of main events is provided in<br />
Table 1:<br />
• MBL – a medium break LOCA with<br />
a failure of the emergency core<br />
cooling system after the emergency<br />
water supply tank inventory is<br />
empty; core degradation starts<br />
delayed; sequence results in a<br />
maximum water inventory in the<br />
containment sump and a late<br />
filtered containment venting.<br />
• ND* – a transient with a failure of<br />
steam generator feedwater supply;<br />
failure of injection of active<br />
emergency core cooling systems;<br />
primary circuit depressurization<br />
procedure to avoid reactor pressure<br />
vessel failure at high-pressure;<br />
core degradation starts early;<br />
sequence results in a minimum<br />
water inventory in the containment<br />
sump and an earlier containment<br />
venting.<br />
The two representative base cases<br />
were already used in earlier analyses<br />
[2], [3] with respect to the reassessment<br />
of other mitigative SAM measures.<br />
In both cases, no melt relocation<br />
from the reactor cavity into the containment<br />
sump after melt penetration<br />
of the biological shield was assumed,<br />
just water ingress into the cavity and<br />
therefore extended steam production.<br />
As melt relocation into the sump with<br />
cooling of the relocated melt amount<br />
seems to be a realistic scenario leading<br />
to reduced production of combustible<br />
gases, two additional variant calculations<br />
were done with melt relocation<br />
into the containment sump. Furthermore,<br />
a series of COCOSYS variant<br />
calculations were carried out in order<br />
to investigate the influence of the<br />
following specific aspects:<br />
• Operation/failure of the RB annulus<br />
exhaust air system installed for<br />
accident conditions.<br />
• Variation of the size of containment<br />
leakages into the reactor<br />
building annulus: design leakage<br />
(base case) and a 10 times larger<br />
leakage.<br />
• Variation of the containment<br />
leakage location in the area of<br />
containment cable penetrations.<br />
Moreover, the efficiency of different<br />
SAM measures for mitigation of the<br />
consequences in the RB annulus,<br />
documented in the SAMG handbook<br />
of the reference plant, was analysed.<br />
These measures are as follows:<br />
• Use of RB annulus air supply/<br />
suction system – provision of a<br />
controlled ventilation to reduce<br />
the hydrogen concentration in the<br />
annulus.<br />
• Use of RB annulus air recirculation<br />
system – mixing of the annulus<br />
atmosphere and elimination of gas<br />
stratification.<br />
• Use of emergency air filtration<br />
system – extraction of air from the<br />
RB annulus through a filtration<br />
system to reduce the release of<br />
radionuclides into the environment.<br />
The following SAM measure was<br />
additionally investigated as a possible<br />
alternative method for hydrogen<br />
reduction in the annulus. It is related<br />
to a optional recommendation of the<br />
RSK [1].<br />
• Implementation of a small number<br />
of PARs in the RB annulus upper<br />
part to prevent combustible gas<br />
mixtures.<br />
2 Results – Quantification<br />
of the effectiveness of<br />
selected AM measures<br />
Selected results are presented in the<br />
following only for one base case<br />
scenario (MBL) with the operation of<br />
RB annulus exhaust air system used in<br />
case of accidents and for some variant<br />
Scenario<br />
Start of steam/water<br />
leak flow into<br />
containment<br />
Start of<br />
core melting<br />
RPV failure and<br />
melt release<br />
into cavity<br />
Water ingression into<br />
cavity and possible<br />
melt release into sump<br />
Start of filtered<br />
containmentventing<br />
ND* 1.4 hr 3.5 hr 6.5 hr 17.1 hr 66.5 hr<br />
MBL 0.0 hr 5.8 hr 8.9 hr 13.5 hr 82.2 hr<br />
| | Tab. 1.<br />
Timing of characteristic events of severe accident progression of base case scenarios.<br />
Environment and Safety<br />
Investigation of Conditions Inside the Reactor Building Annulus of a PWR Plant of KONVOI Type in Case of Severe Accidents with Increased Containment Leakages ı Ivan Bakalov and Martin Sonnenkalb
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
calculations. Moreover, the results of<br />
the two severe accident scenarios<br />
(MBL and ND*) for the base cases<br />
with increased containment leakages<br />
are compared regarding their effect<br />
on the accident consequences.<br />
2.1 Base case with containment<br />
design leakage<br />
The hydrogen concentration in the RB<br />
annulus is presented in Figure 2 (left<br />
side). In the base case no formation of<br />
combustible gas mixtures (> 4 vol.-%<br />
hydrogen) in the RB annulus is<br />
observed during the calculated time<br />
period, and some fire protection<br />
doors and flaps between the separated<br />
rooms of the annulus close automatically<br />
when the atmosphere<br />
temperature reaches 70 °C limiting<br />
the hydrogen and radionuclide inflow<br />
into these areas (Figure 2 right side).<br />
Due to the operation of the RB annulus<br />
exhaust air system, the hydrogen<br />
concentration remains below 1 vol.-%<br />
and decreases further in the long term<br />
when the containment filtered venting<br />
starts reducing the hydrogen leakage<br />
from the containment. Gas stratification<br />
with slightly different gas<br />
concentrations at different elevations<br />
is formed in the annulus gap due to<br />
the operation of the annulus exhaust<br />
air system.<br />
| | Fig. 2.<br />
H 2 concentration in the RB annulus for base case scenario (MBL) with operation of RB annulus exhaust air system;<br />
RB annular gap (left) and RB annulus rooms (right).<br />
| | Fig. 3.<br />
H 2 concentration in the RB annulus for base case (left) and variant case (right) with a 10 times larger containment leakage,<br />
both cases with operation of RB annulus exhaust air system.<br />
ENVIRONMENT AND SAFETY 87<br />
2.2 Variant calculation with a<br />
10 times larger containment<br />
leakage<br />
As already mentioned, one of the<br />
goals is to investigate the conditions in<br />
the RB annulus in case of increased<br />
containment leakages. For this purpose,<br />
a COCOSYS variant calculation<br />
was performed assuming a 10 times<br />
larger containment leakage. The RB<br />
annulus exhaust air system was<br />
assumed to be in operation as in the<br />
base case. It sucks steam-air mixture<br />
from one selected location of the RB<br />
annulus at about 12 m level. Figure 3<br />
compares the hydrogen concentration<br />
and Figure 4 the aerosol concentration<br />
in the base case and the variant<br />
calculation. The overall behaviour in<br />
the RB annulus is the same, but the<br />
variant with 10 times larger containment<br />
leakage leads to the formation of<br />
combustible gas mixtures (> 4 vol.-%<br />
hydrogen) in the upper annulus area<br />
and a higher aerosol concentration<br />
especially in the early accident phase<br />
with large releases from the reactor<br />
circuit during core melting. The<br />
results show that the RB annulus<br />
exhaust air system is not efficient<br />
enough to keep the H 2 concentration<br />
below the lower combustible limit of<br />
| | Fig. 4.<br />
Aerosol concentration in the RB annulus for base case (left) and variant case (right) with a 10 times larger containment leakage,<br />
both cases with operation of RB annulus exhaust air system.<br />
| | Fig. 5.<br />
Comparison of pressure in the containment (left) and MCCI gas generation (right) for the cases with and without melt relocation.<br />
4 vol.-% H2 in all RB annulus areas.<br />
The following three gas concentration<br />
zones are established (Figure 3 right):<br />
• RB annulus above 16 m with<br />
hydrogen concentrations up to<br />
~ 5 vol.-%.<br />
• RB annulus at ~12 m (leak location)<br />
with low hydrogen concentrations<br />
up to ~ 2 vol.-%.<br />
• RB annulus at ~ 6 m and below<br />
with very low hydrogen concentrations<br />
< 0.1 vol.-%.<br />
Environment and Safety<br />
Investigation of Conditions Inside the Reactor Building Annulus of a PWR Plant of KONVOI Type in Case of Severe Accidents with Increased Containment Leakages ı Ivan Bakalov and Martin Sonnenkalb
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
ENVIRONMENT AND SAFETY 88<br />
2.3 Variant calculation with a<br />
10 times larger containment<br />
leakage and consideration<br />
of a potential melt relocation<br />
into containment sump<br />
As already noted, all previous analyses<br />
conducted by GRS have been performed<br />
assuming no melt relocation<br />
from the reactor cavity into the containment<br />
sump after melt penetration<br />
of the biological shield. Since the melt<br />
is very likely to melt-through the biological<br />
shield, a variant calculation<br />
with a 10 times larger containment<br />
leakage and a failure of the RB annulus<br />
exhaust air system was performed<br />
assuming melt relocation into the<br />
containment sump.<br />
After penetration of the biological<br />
shield, the corium spreads into the<br />
containment sump and comes into<br />
contact with the sump water. This<br />
results in a higher steam generation,<br />
which in turn leads to a faster longterm<br />
containment pressurization<br />
compared to the case without melt<br />
relocation (Figure 5). Because of the<br />
higher steam production, the filtered<br />
containment venting starts significantly<br />
earlier than in the case without<br />
melt relocation.<br />
Shortly after the melt relocation<br />
into the sump, the corium solidifies<br />
within a very short time period and<br />
the generation of combustible gases<br />
(H 2 and CO) is terminated. Due to the<br />
overall lower gas production, the H 2<br />
concentrations in the containment,<br />
and thus also in the RB annulus, are<br />
significantly lower compared to those<br />
| | Fig. 6.<br />
Comparison of H 2 concentration in the containment (left) and H 2 concentration in the RB annulus (right) for the cases with and<br />
without melt relocation.<br />
| | Fig. 7.<br />
Comparison of containment pressure (left) and H2 mass generated during MCCI (right) for the MBL and ND* base cases.<br />
in the calculations without melt<br />
relocation (Figure 6) and the lower<br />
combustible limit is no longer reached<br />
in the RB annulus.<br />
2.4 Effect of the selected severe<br />
accident scenarios on the<br />
accident consequences<br />
In order to investigate the effect on<br />
the accident consequences, the results<br />
of the two analyzed severe accident<br />
scenarios (MBL and ND*) have been<br />
compared for the base cases with<br />
increased containment leakages.<br />
A comparison of the containment<br />
pressure response calculated for<br />
the two base cases with increased<br />
containment leakages is shown in<br />
Figure 7 (left). The comparison<br />
demonstrate that in the ND* base<br />
case, the filtered containment venting<br />
starts about 16 hours earlier than in<br />
the MBL base case. Figure 7 (right)<br />
depicts a comparison of the hydrogen<br />
mass generated during the MCCI for<br />
the two accident scenarios. Because of<br />
the earlier venting in the ND* base<br />
case, less hydrogen is generated until<br />
the start of containment depressurization.<br />
This is due to the fact that in the<br />
ND* base case the MCCI duration is<br />
shorter than that in the MBL base<br />
case. Hence, for the ND* case, a total<br />
amount of hydrogen of about 3,700 kg<br />
is generated, while for the MBL case,<br />
the total hydrogen mass, generated<br />
until the start time of filtered containment<br />
venting, is about 4,000 kg. The<br />
hydrogen concentrations in the RB<br />
annulus calculated for the two base<br />
case scenarios are compared in<br />
Figure 8. Due to the earlier start of<br />
containment venting in the ND* base<br />
case the maximum hydrogen concentration<br />
in the RB annulus is lower than<br />
that in the MBL base case. From the<br />
comparison it is evident that the<br />
hydrogen lower combustible limit of<br />
4 vol.% is not exceeded until the<br />
beginning of the containment depressurization.<br />
| | Fig. 8.<br />
Comparison of H 2 concentration in the RB annulus ring (left) and H 2 concentration in the RB annulus rooms (right) for the MBL and<br />
ND* base cases.<br />
2.5 Variant calculations with a<br />
10 times larger containment<br />
leakage and AM measures<br />
As part of the assessment of potential<br />
mitigative AM measures the efficiency<br />
of the RB annulus air supply/suction<br />
system to reduce the hydrogen concentration<br />
in the RB annulus was<br />
investigated. For this purpose, a<br />
variant calculation with a 10 times<br />
larger design leakage and a failure of<br />
the RB annulus exhaust air system<br />
was carried out (Figure 9 left) and<br />
another one assuming that the RB air<br />
supply/exhaust systems are put into<br />
Environment and Safety<br />
Investigation of Conditions Inside the Reactor Building Annulus of a PWR Plant of KONVOI Type in Case of Severe Accidents with Increased Containment Leakages ı Ivan Bakalov and Martin Sonnenkalb
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
operation as AM measure at approx.<br />
50 h after the accident onset (Figure 9<br />
right). The results show a significantly<br />
increased hydrogen concentration in<br />
the RB annulus in case of a failure of<br />
the RB annulus exhaust air system<br />
(Figure 9 left).<br />
Further, in this case the use of<br />
the RB annulus air supply/exhaust<br />
systems is efficient to reduce the<br />
hydrogen concentration and prevent<br />
the formation of combustible gas<br />
mixtures in the annulus rooms. With<br />
the operation of the system the hydrogen<br />
is removed from the annulus<br />
quickly and the hydrogen concentration<br />
remains below 1 vol.-% for the<br />
long term. In that case, the use of the<br />
emergency air filtration system of the<br />
plant is needed in addition to limit<br />
the radionuclide releases into the<br />
environment.<br />
In addition, a possible alternative<br />
method for hydrogen reduction in the<br />
annulus was investigated assuming<br />
the installation of a small number of<br />
medium size PARs in the upper RB<br />
annulus (Figure 10 right). The results<br />
are compared with a variant calculation<br />
with a 10 times larger design<br />
leakage and failure of the RB annulus<br />
exhaust air system (Figure 10 left).<br />
The results show that already the<br />
implementation of PARs of medium<br />
size can significantly reduce the<br />
hydrogen concentration in the RB<br />
annulus and keep it well below<br />
lower combustible limits. The hydrogen<br />
depletion starts at approx. 40 h<br />
(150,000 s) after the accident onset<br />
if the concentration exceeds about<br />
1 to 2 vol.-%. Thus, an AM concept<br />
with the installation of some PARs in<br />
the annulus is considered a very<br />
efficient mitigation measure for preventing<br />
formation of combustible gas<br />
mixtures in the RB annulus not just in<br />
the case presented.<br />
3 Conclusions<br />
The behaviour of hydrogen as well as<br />
aerosol and noble gases released into<br />
the reactor building annulus of a<br />
German PWR KONVOI reference plant<br />
resulting from increased containment<br />
leakages under severe accident conditions<br />
was investigated using the<br />
GRS code COCOSYS. Two representative<br />
and different severe accident<br />
scenarios – the base cases – have been<br />
selected for the analyses.<br />
The calculation results show no<br />
formation of combustible gas mixtures<br />
in the RB annulus during the observation<br />
period for the base case with<br />
containment design leakage and<br />
operation of RB annulus exhaust<br />
| | Fig. 9.<br />
H 2 concentration in the RB annulus for variant cases with 10 times larger leakages and failure of RB annulus exhaust air system (left)<br />
and with AM measure “operation of RB annulus air supply/exhaust systems” (right).<br />
| | Fig. 10.<br />
H 2 concentration in the RB annulus for variant cases with 10 times larger leakages and failure of RB annulus exhaust air system (left)<br />
and with AM measure “PARs in the RB annulus” (right).<br />
air system. It was identified that in<br />
this case separate annulus rooms are<br />
isolated at an early stage by the automatic<br />
closing of fire protection doors,<br />
thus preventing a further increase in<br />
the hydrogen concentration in these<br />
rooms.<br />
In contrast, the variant calculation<br />
with a 10 times larger containment<br />
design leakage leads to formation of<br />
combustible mixtures in the upper RB<br />
annulus area. In this case, the RB<br />
annulus exhaust air system is not<br />
efficient enough to prevent formation<br />
of combustible gas mixtures in the<br />
upper RB annulus area.<br />
Further, the variant calculation<br />
assuming melt relocation into the<br />
containment sump demonstrated that<br />
the corium spreading into the sump<br />
results in a higher steam generation,<br />
which leads to a faster long-term<br />
containment pressurization. After the<br />
melt relocation into the sump, the<br />
corium solidifies within a short time<br />
and the generation of combustible<br />
gases (H 2 and CO) coming from<br />
MCCI is terminated. As a result, the<br />
H 2 concentrations in the containment<br />
as well as in the RB annulus are<br />
significantly lower compared to those<br />
in the case without melt relocation. In<br />
this case, the lower combustible limit<br />
of 4 vol.% in the RB annulus is no<br />
longer reached.<br />
Moreover, the results of the two<br />
analyzed severe accident scenarios<br />
(MBL and ND*) were compared in<br />
order to investigate their effect on<br />
the accident consequences. From the<br />
comparison it was identified that in<br />
the ND* base case, the filtered<br />
containment venting starts about<br />
16 hours earlier than in the MBL base<br />
case. As a result, the maximum hydrogen<br />
concentration in the RB annulus,<br />
calculated for the ND* base case, is<br />
lower than that in the MBL base case.<br />
The comparison showed that in the<br />
ND* base case the hydrogen concentration<br />
does not exceed the lower<br />
combustible limit of 4 vol.% until the<br />
beginning of the containment depressurization.<br />
Within the scope of the project, the<br />
efficiency of different AM measures<br />
for mitigation of accident consequences<br />
in the reactor building annulus<br />
was analyzed. The assessment<br />
results show that the operation of RB<br />
annulus air supply/suction system<br />
significantly reduces the hydrogen<br />
concentration and prevents formation<br />
of combustible gas mixtures in RB<br />
annulus. Therefore, the use of these<br />
ventilation systems is considered as a<br />
very promising accident management<br />
measure for reducing the hydrogen<br />
concentration in the reactor building<br />
annulus. However, in that case the<br />
ENVIRONMENT AND SAFETY 89<br />
Environment and Safety<br />
Investigation of Conditions Inside the Reactor Building Annulus of a PWR Plant of KONVOI Type in Case of Severe Accidents with Increased Containment Leakages ı Ivan Bakalov and Martin Sonnenkalb
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
ENVIRONMENT AND SAFETY 90<br />
emergency air filtration system of<br />
the plant is needed in addition to limit<br />
the radionuclide releases into the<br />
environment.<br />
With respect to mitigation of the<br />
hydrogen risk in the annulus it is<br />
demonstrated that the implementation<br />
of a small number of PARs would<br />
be a very efficient and fully passive<br />
mitigation measure without additional<br />
aerosol release into the environment.<br />
Acknowledgments<br />
The authors like to acknowledge the<br />
German Federal Ministry for the<br />
Environment, Nature Conservation,<br />
Building and Nuclear Safety for the<br />
financial support of the project<br />
3615R01345.<br />
References<br />
[1] Recommendation of German Reactor<br />
Safety Commission (RSK): Hydrogen<br />
Release from Containment. Annex of<br />
the Proceedings of 475 th meeting of<br />
RSK, 15.04.2015.<br />
[2] Band, S., Schwarz, S., Sonnenkalb, M.:<br />
Nachweis der Wirksamkeit von<br />
H 2 -Rekombinatoren auf der Basis<br />
ergänzender analytischer Untersuchungen<br />
mit COCOSYS für die<br />
Referenzanlage GKN-2. Final Report<br />
of BMUB project 3609R01375,<br />
GRS-A-3652, March 2012.<br />
[3] Schwarz, S., Sonnenkalb, M.: Analyse<br />
der Belastung von Gleitdruckventuriwäschern<br />
in SHB-Ventingsystemen<br />
von DWR KONVOI und<br />
SWR-72 bei Unfällen. Final Report<br />
of BMUB project 3613R01320,<br />
GRS-A-3820, August 2015.<br />
Authors<br />
Ivan Bakalov<br />
Research Fellow<br />
Gesellschaft für Anlagen- und<br />
Reaktorsicherheit (GRS) gGmbH,<br />
Kurfürstendamm 200<br />
10719 Berlin, Germany<br />
Dr. Martin Sonnenkalb<br />
Department Head<br />
Gesellschaft für Anlagen- und<br />
Reaktorsicherheit (GRS) gGmbH,<br />
Schwertnergasse 1<br />
50667 Cologne, Germany<br />
Sensitivity Analysis of MIDAS Tests Using<br />
SPACE Code: Effect of Nodalization<br />
Shin Eom, Seung-Jong Oh and Aya Diab<br />
1 Introduction The SPACE thermal hydraulic analysis computer code has been developed by KHNP (Korea<br />
Hydro and Nuclear Power) [1]. The SPACE code is based on the three-field governing equations (vapor, continuous<br />
liquid, and droplet). It improves the accuracy by solving the mass, energy, and momentum conservation equations for<br />
each phase and adopts the proven numerical methods as well as the models for various thermal hydraulic phenomena.<br />
With the new code, the best estimate<br />
LOCA (Loss Of Coolant Accident)<br />
methodology needs to be reestablished.<br />
For APR1400 LBLOCA (Large<br />
Break LOCA, APR1000: Advanced<br />
Power Reactor 1000 MWe), KREM [2]<br />
has been developed one of the best<br />
estimate methodology using RELAP5<br />
code [3, 4]. With the new code, one<br />
needs to look at the code performance<br />
to develop best estimate + uncertainty<br />
method. In this paper, as a part of the<br />
development effort, we focus on the<br />
impact of nodalization on the code<br />
predictions, more specifically, on the<br />
ECC bypass phenomenon.<br />
For APR1400 LBLOCA, ECC bypass<br />
phenomenon is one of the important<br />
phenomena which would occur in the<br />
downcomer during the reflood phase<br />
of LOCA [5]. To study the ECC bypass<br />
phenomenon, KAERI carried out the<br />
ECC bypass tests using the MIDAS<br />
facility [6, 7, 8]. MIDAS simulation is a<br />
part of the assessment of the KREM.<br />
One of the important parameters<br />
for the MIDAS test is ECC bypass fraction.<br />
The results for each nodalization<br />
were compared with MIDAS test data.<br />
The main aim of this study is therefore<br />
to examine the sensitivity of the<br />
SPACE code to the number of thermal<br />
hydraulic channels in the downcomer<br />
region.<br />
| | Fig. 1.<br />
Isometric View of the MIDAS Facility [7].<br />
| | Fig. 2.<br />
Top View of the MIDAS Facility Downcomer [7].<br />
2 MIDAS test<br />
The MIDAS test facility is a steamwater<br />
separate effect test facility<br />
which is scaled down from APR1400<br />
[9]. It is focused on the investigation<br />
of the ECC bypass phenomenon in the<br />
downcomer annulus. The test condition<br />
was determined, based on the<br />
analysis of the TRAC (Transient<br />
Reactor Analysis Code) [10]. The<br />
isometric and top view of the MIDAS<br />
facility is depicted in Figure 1 and<br />
Figure 2.<br />
To investigate the effect of the DVI<br />
injection nozzle location on the ECC<br />
bypass fraction, fifteen separate effect<br />
Environment and Safety<br />
Sensitivity Analysis of MIDAS Tests Using SPACE Code: Effect of Nodalization ı Shin Eom, Seung-Jong Oh and Aya Diab
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
tests have been performed with only<br />
DVI-2 (farthest from the broken cold<br />
leg), only DVI-4 (closest to the broken<br />
cold leg), and DVI-2&4 with both<br />
injection nozzles activated. Table 1<br />
provides the experimental conditions<br />
for the 15 tests.<br />
The bypass fractions of the MIDAS<br />
experiment for the test conditions are<br />
presented in the Figure 3. The test<br />
results show that the ECC bypass<br />
fraction is highly dependent on the<br />
injection nozzle location with respect<br />
to the broken leg as well as the injected<br />
steam flow rate.<br />
Injecting through the nozzle closet<br />
to the broken leg (DVI-4 tests)<br />
show that the direct bypass fraction<br />
increases drastically for a steam flow<br />
rate above 0.7 kg/s. This is expected<br />
since at a higher steam flow rate, the<br />
relative speed between the two fluid<br />
streams becomes higher resulting in a<br />
higher shear effect.<br />
On the other hand, injecting<br />
through the nozzle farthest to the<br />
broken leg (DVI-2 test) dramatically<br />
decreases the bypass fraction, and<br />
accordingly most of the injected ECC<br />
water penetrates into the lower downcomer.<br />
This is primarily due to the<br />
lower interfacial interaction between<br />
the two streams. As a result of the<br />
spatial separation, the ECCS stream<br />
becomes more inertially driven.<br />
With both nozzles activated<br />
( DVI-2&4 tests), the bypass ratio<br />
increases with steam flow rate but<br />
at a much slower rate as compared<br />
to that of DVI-4 tests. This may be<br />
attributed to lower interfacial-interaction<br />
between the injected steam and<br />
ECCS stream for the combined case.<br />
Test<br />
No.<br />
Steam<br />
in (kg/s)<br />
ECCS Injection<br />
Nozzle<br />
KM100 1.7924 DVI-2&4<br />
KM101 1.6149 DVI-2&4<br />
KM1<strong>02</strong> 1.3753 DVI-2&4<br />
KM103 1.1711 DVI-2&4<br />
KM104 0.0493 DVI-2&4<br />
KM105 0.9378 DVI-2&4<br />
KM106 0.8592 DVI-2&4<br />
KM107 0.8096 DVI-2&4<br />
KM108 0.7540 DVI-2&4<br />
KM109 1.8086 DVI-2<br />
KM110 1.0555 DVI-4<br />
KM111 0.8995 DVI-4<br />
KM112 0.7991 DVI-4<br />
KM113 0.7360 DVI-4<br />
3 MIDAS Modeling<br />
for the SPACE Code<br />
A SPACE model of the MIDAS facility<br />
is developed with three different<br />
nodalization schemes as shown in<br />
Figure 4 to Figure 6. The downcomer<br />
is modeled as an annulus component<br />
with 4, 6, and 12 circumferential<br />
channels. A nodalization sensitivity<br />
analysis for the ECC bypass phenomenon<br />
was performed using the SPACE<br />
code version 3.0.<br />
For the KREM which has best<br />
estimate LOCA methodology using<br />
RELAP5 code, the downcomer was<br />
represented with 6 channels [4]. The<br />
comparison with MIDAS test results as<br />
a part of the code validation showed<br />
that RELAP5 code over-predicts the<br />
bypass fraction for low steam flow<br />
cases while predicts reasonably for<br />
higher steam flow cases.<br />
The intact cold legs (CL-1, CL-2,<br />
and CL-3) are connected to the<br />
annulus component using a normal<br />
junction with branch components. A<br />
time-dependent volume and a<br />
time-dependent junction were used to<br />
admit the steam flow rate through<br />
each cold leg. The broken cold leg<br />
(CL-4) is connected to the annulus<br />
component using a normal junction<br />
with a branch component.<br />
The DVI nozzle (DVI-4) closest to<br />
the broken leg is connected to the<br />
same hydraulic channel as the break<br />
(CL-4) whereas the DVI nozzle<br />
(DVI-2) farthest from the break shares<br />
the same hydraulic channel as the<br />
intact cold leg (CL-1) as shown in<br />
Figure 4 to Figure 6. The drain valve<br />
was modeled using a trip valve<br />
component which would open if the<br />
water level of the lower downcomer<br />
becomes higher than the set point.<br />
The hot legs, (HL-1 and HL-2)<br />
which are located between CL-1 and<br />
CL-2, and between CL-3 and CL-4,<br />
respectively, are modeled as blunt<br />
bodies that penetrate the downcomer.<br />
The flow areas were calculated by<br />
using the gap width, perimeter, as<br />
well as other geometric parameters at<br />
this section to estimate the equivalent<br />
thermal hydraulic diameter.<br />
The direct ECCS bypass fraction<br />
is calculated based on the flow rates<br />
of ECCS injection, steam injection,<br />
and drain flow rate at the lower downcomer<br />
as follows:<br />
Bypass fraction =<br />
M Water_out<br />
M SI_in +M Condensate<br />
| | Fig. 3.<br />
ECC Bypass Fraction of MIDAS Tests.<br />
M Steam_in is the steam injection mass<br />
flow rate, and M Condensate is the<br />
condensate mass flow rate calculated<br />
as follows:<br />
M Condensate = M Steam_in – M Steam_out<br />
4 Results and Discussion<br />
The model predictions of the bypass<br />
fraction for all three nodalization<br />
cases (4, 6 and 12 channels) were<br />
compared to the experimental data.<br />
The sample standard deviation of the<br />
differences between measured values<br />
and predicted values, RMSE (Root<br />
Mean Square Error), are presented in<br />
Table 2.<br />
For the case with DVI-2 injection<br />
only (KM109), the RMSEs are<br />
relatively small and acceptable for all<br />
three cases with 0.056 for 4 channels<br />
as a representative case. For the<br />
injection through DVI-4 only (KM110<br />
~ KM114), the code over-predicts the<br />
bypass fraction. This is more distinct<br />
at lower steam flow and for finer<br />
nodalization (e.g. 12 channels). For<br />
the cases with injection through both<br />
ENVIRONMENT AND SAFETY 91<br />
KM114 0.6879 DVI-4<br />
| | Tab. 1.<br />
Experimental Conditions of MIDAS Tests [7].<br />
where, M SI_in is the total ECCS injection<br />
mass flow rate, M Water_out is the<br />
discharged liquid mass flow rate,<br />
| | Fig. 4.<br />
MIDAS Nodalization Scheme with 4 Channels.<br />
Environment and Safety<br />
Sensitivity Analysis of MIDAS Tests Using SPACE Code: Effect of Nodalization ı Shin Eom, Seung-Jong Oh and Aya Diab
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
ENVIRONMENT AND SAFETY 92<br />
| | Fig. 5.<br />
MIDAS Nodalization Scheme with 6 Channels.<br />
| | Fig. 6.<br />
MIDAS Nodalization Scheme with 12 Channels.<br />
Test No.<br />
Steam Flow Rate<br />
(kg/s)<br />
| | Tab. 2.<br />
RMSE Calculated Results of Bypass Fraction with Measured Data.<br />
DVI-2 and DVI-4, the steam flow<br />
rate seems to govern the prediction<br />
accuracy. In case of high steam flow<br />
rate tests (≥ 1.1 kg/s), the SPACE<br />
code predicted the bypass fraction<br />
well regardless of the number of<br />
channels chosen. For the low steam<br />
flow rate tests (≤ 1.1 kg/s), the RMSE<br />
is ≥ 0.16 as shown in Table 2. More<br />
detailed examination is presented<br />
below.<br />
4.1 Results of High Steam Flow<br />
Rate Tests<br />
The results for the high steam flow<br />
rate tests (KM100 ~ KM103, and<br />
Number of Channels<br />
4 6 12<br />
KM109 1.8086 0.056 0.078 0.005<br />
KM100 ~ 103 ≥ 1.1 0.017 0.019 0.017<br />
KM104 ~ 108<br />
0.161 0.211 0.287<br />
≤ 1.1<br />
KM110 ~ 114 0.252 0.334 0.462<br />
| | Fig. 7.<br />
Comparison of the Measured and Calculated ECC Bypass Fraction for the<br />
High Steam Flow Cases.<br />
KM109) are presented in Figure 7. For<br />
the high steam flow rate tests, the<br />
SPACE code predicts the bypass<br />
fraction relatively well for all<br />
nodalization cases.<br />
The liquid flow pattern for the<br />
KM100 test (highest steam flow rate<br />
test) of each nodalization case are<br />
presented in Figure 8 to Figure 10.<br />
The liquid flow pattern for the all<br />
nodalization cases are quite similar.<br />
The direct bypass phenomena occurs<br />
in the upper region of the downcomer<br />
as the ECCS flow joins the high<br />
velocity steam from the intact cold leg<br />
and is swept away through the broken<br />
cold leg. In the case of tests with a<br />
high steam flow rate, the result of<br />
the 4 channels nodalization is similar<br />
to that of 6 and 12 channels. Hence,<br />
the 4 channels representation is considered<br />
a reasonable approximation.<br />
4.2 Results of Low Steam Flow<br />
Rate Tests<br />
The results for the low steam flow rate<br />
tests (KM104 ~108 and KM110 ~114)<br />
are presented in Figure 11. Contrary<br />
to the high steam flow rate cases, for<br />
the low steam flow rate tests, the<br />
SPACE code over-predicts the bypass<br />
fraction for the all nodalization cases.<br />
The liquid and vapor flow patterns<br />
of the 6 channels case for the lowest<br />
steam flow rate test (KM114) are<br />
presented in Figure 12 and Figure 13,<br />
respectively. Most of the liquid<br />
injected from the DVI nozzle is swept<br />
with the steam flow through the<br />
break. The test indicated some downward<br />
liquid flow at this steam flow<br />
rate.<br />
In the SPACE code, the interfacial<br />
friction model is dependent on the<br />
flow regime of the control volume.<br />
Thus, for quantitative agreement with<br />
the MIDAS experimental measurements,<br />
the estimation of the flow<br />
regime has to be properly predicted to<br />
accurately estimate the bypass flow in<br />
the upper downcomer. The SPACE<br />
code selects the annular mist flow<br />
regime based on the volume average<br />
conditions, which explains the deviation<br />
between the code prediction and<br />
MIDAS tests in the case of low steam<br />
flow rate.<br />
4.3 Results of Condensation<br />
Fraction<br />
It is worthy to note that for all the<br />
studied cases, the code under-predicts<br />
the condensation fraction as shown in<br />
the Figure 14. The RMSE based on<br />
calculated condensation fraction with<br />
the measured condensation fraction<br />
data are presented in Table 3. The<br />
under-prediction tendency is more<br />
distinct for finer nodalization (e.g. 12<br />
channels) as depicted in Table 3. This<br />
may clearly be tied to the heat transfer<br />
correlation which in turn depends on<br />
the flow regime. Due to mass conservation,<br />
the lower condensation rate<br />
leads to over-estimation of the bypass<br />
Environment and Safety<br />
Sensitivity Analysis of MIDAS Tests Using SPACE Code: Effect of Nodalization ı Shin Eom, Seung-Jong Oh and Aya Diab
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
| | Fig. 8.<br />
Liquid Flow Pattern of KM100 Test Calculation<br />
with 4 Channels Nodalization.<br />
| | Fig. 9.<br />
Liquid Flow Pattern of KM100 Test Calculation<br />
with 6 Channels Nodalization.<br />
| | Fig. 10.<br />
Liquid Flow Pattern of KM100 Test Calculation<br />
with 12 Channels Nodalization.<br />
ENVIRONMENT AND SAFETY 93<br />
| | Fig. 11.<br />
Comparison of the Measured and Calculated ECC Bypass Fraction for Low<br />
Steam Flow Cases.<br />
| | Fig. 12.<br />
Liquid Flow Pattern of KM114 Test Calculation<br />
with 6 Channels Nodalization.<br />
| | Fig. 13.<br />
Vapor Flow Pattern of KM114 Test Calculation<br />
with 6 Channels Nodalization.<br />
fraction. The problem is aggravated<br />
for the lower steam flow rate tests,<br />
since the phase change effect overshadows<br />
the convective effect. It is<br />
hypothesized that the bypass flow<br />
may be influenced by the interplay<br />
between thermal and inertial effects,<br />
particularly at the lower steam flow<br />
rate test conditions.<br />
5 DVI Location Effect for<br />
the Low Steam Flow Rate<br />
Test<br />
As shown in the Figure 4 to Figure 6,<br />
the DVI channels and the broken<br />
channel share the same channel. With<br />
this nodalization, the most of the<br />
injected liquid flows into the control<br />
volume directly connected to broken<br />
cold leg. Since the steam flow for this<br />
volume is very high, the flow regime<br />
becomes co-current annular mist flow.<br />
With co-current annular flow, the<br />
injected water from the DVI swept<br />
away to the break.<br />
To further examine this phenomenon,<br />
we carried out an additional<br />
calculation. We selected the 6 channels<br />
representation. This time, however,<br />
the DVI-4 is connected to a<br />
channel next to the channel where<br />
broken cold leg is connected as shown<br />
in the Figure 15. The DVI channels<br />
were separated from the broken channel<br />
(or cold leg channel), artificially.<br />
The bypass and condensation<br />
fraction results of the existing and new<br />
nodalization cases with 6 channels are<br />
compared with KM114 test conditions<br />
in Table 4. Clearly, the new nodalization<br />
better predicts the bypass and<br />
condensation fraction. While the<br />
existing nodalization predicts a bypass<br />
fraction of 0.714, the new nodalization<br />
predicts a bypass fraction of 0.091<br />
with only about 16 % deviation.<br />
| | Fig. 14.<br />
Comparison of the Measured and Calculated Condensation Fraction.<br />
| | Fig. 15.<br />
New Nodalization Scheme for 6 Channels.<br />
Test No.<br />
Steam Flow Rate<br />
(kg/s)<br />
Number of Channels<br />
4 6 12<br />
Case<br />
Bypass<br />
Fraction<br />
Condensation<br />
Fraction<br />
KM109 1.8086 0.<strong>02</strong>9 0.036 0.052<br />
KM100 ~ 103 ≥ 1.1 0.078 0.094 0.116<br />
KM104 ~ 108<br />
0.090 0.113 0.144<br />
≤ 1.1<br />
KM110 ~ 114 0.082 0.103 0.138<br />
| | Tab. 3.<br />
RMSE Calculated Results of Condensation Fraction with Measured Data.<br />
Measured value 0.109 0.231<br />
Existing nodalization 0.714 0.131<br />
New nodalization 0.091 0.203<br />
| | Tab. 4.<br />
Bypass and Condensation Fraction Results Comparison<br />
in Case of 6 Channels for KM114 Test.<br />
Environment and Safety<br />
Sensitivity Analysis of MIDAS Tests Using SPACE Code: Effect of Nodalization ı Shin Eom, Seung-Jong Oh and Aya Diab
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
ENVIRONMENT AND SAFETY 94<br />
| | Fig. 16.<br />
Liquid Flow Pattern of KM114 Test Calculation<br />
with 6 Channels of New Nodalization.<br />
Similarly, while the existing nodalization<br />
predicts a condensation fraction<br />
of 0.131, the new nodalization predicts<br />
a condensation fraction of 0.203 with<br />
only about 12 % deviation.<br />
The liquid and vapor flow pattern<br />
diagrams of the 6 channels case for<br />
the KM114 test are presented in<br />
Figure 16 and Figure 17 for the new<br />
nodalization, respectively. The liquid<br />
flow issuing from DVI-4 becomes<br />
continuous downward flow as shown<br />
in Figure 16. This shows the importance<br />
of proper representation of the<br />
flow regime. Given that the new<br />
nodalization does not strictly reflect<br />
the actual experimental arrangement,<br />
the proper nodalization scheme needs<br />
to be further developed.<br />
6 Conclusions<br />
In this paper, a nodalization sensitivity<br />
analysis for the MIDAS test was<br />
performed using the SPACE code.<br />
Three cases were modeled: 4, 6, and<br />
12 channels.<br />
In the case of high steam flow rate<br />
with DVI injection from both sides<br />
tests (KM100 ~ KM103) and DVI-2<br />
injection test (KM109), the SPACE<br />
code estimated the bypass fraction<br />
relatively accurately and the nodalization<br />
scheme does not affect<br />
the code results much. From the<br />
efficiency, 4 channel representation<br />
is recommended for SPACE code<br />
nodalization.<br />
Similar to RELAP5 calculation, the<br />
SPACE code was unable to accurately<br />
predict the bypass fraction for the low<br />
steam flow rate MIDAS tests (KM104<br />
~ 108 and KM 110 ~ 114) regardless<br />
of the nodalization used. From a<br />
safety perspective, over-prediction of<br />
the bypass flow is conservative for a<br />
LOCA simulation.<br />
The over-prediction at low steam<br />
flow may be attributed to the difficulty<br />
to correctly represent the flow regime<br />
in the vicinity of the broken cold leg.<br />
This led to under-prediction of<br />
| | Fig. 17.<br />
Vapor Flow Pattern of KM114 Test Calculation<br />
with 6 Channels of New Nodalization.<br />
condensation rate and over-prediction<br />
of interfacial shear. When the DVI<br />
channels were horizontally shifted<br />
with respect to the break channel, the<br />
SPACE better predicted the bypass<br />
fraction for the lowest steam flow rate<br />
MIDAS test (KM114). This fictitious fix<br />
proves the hypothesis but the result<br />
should be treated with discretion.<br />
7 Acknowledgments<br />
This research was supported by the<br />
2017 Research Fund of the KINGS<br />
(KEPCO International Nuclear<br />
Graduate School), Republic of Korea.<br />
References<br />
[1] ***, KHNP, Topical Report on the SPACE<br />
code for Nuclear Power Plant Design,<br />
KHNP/TR-0032/2017, 2017.<br />
[2] S.Y. Lee and C.H. Ban, Code-Accuracy-<br />
Based Uncertainty Estimation (CABUE)<br />
Methodology for Large-Break Loss-of-<br />
Coolant Accidents, Nuclear Technology,<br />
Vol. 148 Issue 3, pp.335-347, 2004.<br />
[3] ***, KHNP, Topical Report for the<br />
LBLOCA Best-Estimate Evaluation<br />
Methodology of the APR1400 Type<br />
Nuclear Power Plant, KHNP/TR-0018/<br />
2010, 2010.<br />
[4] S.W. Lee and S.J. Oh, APR1400 Large<br />
Break Loss of Coolant Accident Analysis<br />
using KREM methodologies, 2003 KNS<br />
Autumn Meeting, KNS, 2003.<br />
[5] S.W. Lee, H.G. Kim, and S.J. Oh,<br />
Assessment of APR1400 ECCS Capability<br />
against Large-Break LOCA Scenario<br />
by RELAP5/MOD3 Code, Nuclear<br />
Technology, Vol. 158 Issue 3,<br />
pp.396-407, 2007.<br />
[6] B.J. Yun, H.K. Cho, T.S. Kwon, C.H. Song,<br />
J.K. Park, and G.C. Park, Experimental<br />
Observation on the Hydraulic<br />
Phenomena in the KNGR Downcomer<br />
during LBLOCA Reflood Phase, 2000<br />
KNS Spring Meeting, KNS, 2000.<br />
[7] ***, KAERI, Direct Vessel Injection Test<br />
Using the MIDAS Test Facility-ECC Direct<br />
Bypass Test, MIDAS-QLR-009, 2001.<br />
[8] W.A. Carbiener and R.A. Cudnik,<br />
Similitude Considerations for Modeling<br />
Nuclear Reactor Blowdowns, Tran. Am.<br />
Nucl. Soc., Vol. 12, pp.361, 1969.<br />
[9] B.J. Yun et al., Direct ECC Bypass<br />
Phenomena in the MIDAS Test Facility<br />
during LBLOCA Reflood Phase,<br />
KNS Vol. 34, pp.421-432, 20<strong>02</strong>.<br />
[10] ***, KAERI, Scaling Analysis of the<br />
Thermal Hydraulic Test Facility for the<br />
Large Break LOCA of KNGR, KAERI/<br />
TR-1878/2001, 2001.<br />
Authors<br />
Shin Eom<br />
Graduate Student<br />
Professor Dr. Seung-Jong Oh<br />
Professor Dr. Aya Diab<br />
Department of NPP Engineering<br />
KEPCO International Nuclear<br />
Graduate School (KINGS)<br />
Ulsan, Korea<br />
Environment and Safety<br />
Sensitivity Analysis of MIDAS Tests Using SPACE Code: Effect of Nodalization ı Shin Eom, Seung-Jong Oh and Aya Diab
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
The Application of Knowledge<br />
Management and TRIZ for solving the<br />
Safe Shutdown Capability in Case of Fire<br />
Alarms in Nuclear Power Plants<br />
Chia-Nan Wang, Hsin-Po Chen, Ming-Hsien Hsueh and Fong-Li Chin<br />
1 Introduction The 2011 the Fukushima nuclear disaster in Japan was caused by a failure in the safe shutdown<br />
system. The severing of power systems incapacitated several of the shutdown devices, thereby hindering the removal of<br />
excess heat from the reactor. Under these conditions, zirconium on the protective cover of the fuel rods reacted with the<br />
cooling water to produce hydrogen gas. The resulting explosion fractured the containment building, thereby allowing<br />
the escape of radioactive materials into the surrounding environment.<br />
Nuclear power plants designed in<br />
the U.S. must conform to regulations<br />
outlined by the Nuclear Regulatory<br />
Commission (NRC). The safe shutdown<br />
capabilities of a facility are<br />
documented in the Final Safety<br />
Analysis Report (FSAR), which must<br />
be submitted to authorities prior to<br />
the licensing of operations. Facility<br />
upgrades are also subject to approval.<br />
Operating specifications include<br />
shut-down procedures to be implemented<br />
in the event of an earthquake<br />
or other environmental disaster. In<br />
1979, the NRC proposed a number of<br />
fire safety measures [10CFR50 App.R];<br />
however, the complexity of nuclear<br />
facilities has greatly hindered implementation<br />
and enforcement. Nuclear<br />
power plants are required to have two<br />
independent safe shutdown systems,<br />
either of which must be able to<br />
manage plant operations during the<br />
transition from operating phase to<br />
cold shutdown. The simultaneous<br />
failure of both of systems would lead<br />
to a catastrophic collapse of the entire<br />
system. This study sought to sought to<br />
improve the safe shutdown performance<br />
of nuclear power plants in the<br />
event of fire. We compiled a wide<br />
range of data pertaining to post-fire<br />
safe shutdown of nuclear power<br />
plants, while dealing with each system<br />
and its components as discrete units.<br />
Our main objectives were as follows:<br />
1. To compile a knowledge base<br />
of issues related to hazards in<br />
nuclear power plants: The<br />
knowledge base defines the safe<br />
shutdown system used in each fire<br />
zone, describes the components<br />
used in each system, and organizes<br />
the shutdown processes in the<br />
form of a flowchart.<br />
2. To assess the components of the<br />
safe shutdown systems using the<br />
Teoriya Resheniya Izobreatatelskih<br />
Zadatch (TRIZ) method:<br />
We defined the attributes and<br />
parameters of various problems<br />
associated with safe shutdown<br />
equipment and developed models<br />
for each individual problem using<br />
TRIZ to identify feasible means of<br />
improvement.<br />
3. Improve the safety regulations<br />
of nuclear power plants based<br />
on case studies and a literature<br />
review: We formulated a novel<br />
approach to the analysis of case<br />
studies with the aim of facilitating<br />
the identification of omissions<br />
and flaws in current evaluation<br />
standards.<br />
2 Literature review<br />
Prior to 1974, there were only two<br />
clauses in the national fire regulations<br />
(U.S.): 10CFR50 Appendix A (fire<br />
protection) General Design Criteria<br />
(GDC) and R.G 1.70.4. In November<br />
1975, after the fire at Browns Ferry<br />
Nuclear Power Plant, the NRC<br />
published the Standard Review Plan<br />
9.5-1. In May 1976, the BTP APCSB<br />
9.5-1App.A (Nuclear Power Plant<br />
Fire Guidelines) came into effect for<br />
nuclear power plants seeking to obtain<br />
building permits after July 1 [NRC,<br />
1976], 1976. In August 1977, the NRC<br />
published the Generic Letter 77-<strong>02</strong><br />
[USNRC, 1977], addressing issues<br />
pertaining to administration, the<br />
regulation of organizations, firefighting<br />
procedures, and quality<br />
control measures. In 1980, the NRC<br />
drew up 10CFR50 Appendix R (fire<br />
protection program), detailing the<br />
requirements of all nuclear power<br />
plants that went into operation prior<br />
to January 1st 1979. In February 1981,<br />
the NRC announced 10CFR50.48<br />
(fire protection) as the standing<br />
regulations for nuclear power plant<br />
fire safety [Information Notice, 1984].<br />
Compliance with 10 CFR 50 App. R<br />
was not mandatory for all nuclear<br />
power plants operating before<br />
January 1, 1979 (pre-1979 plants);<br />
however, they had to follow the<br />
basic design requirements. In contrast,<br />
nuclear power plants operating<br />
since January 1, 1979 (post-1979<br />
plants) have had to comply with BTP<br />
CMEB 9.5-1, Revision 2 [CRF, 1979]<br />
In the case study of this paper, an<br />
operating license was obtained for<br />
reactor 1 on July 27, 1984. It should<br />
therefore have been subject to BTP<br />
CMEB 9.5-1 Rev.2 [July 1981]; however,<br />
Section 9.5.1 of the FSAR from<br />
the later Maanshan Nuclear Power<br />
Plant refers to Appendix A to APCB<br />
9.5-1 [NRC Branch Technical Position,<br />
1981]. As a result, both were used<br />
as references. Taiwan uses the fire<br />
regulations of 10 CFR 50 Appendix R<br />
as the basis for fire inspections;<br />
however, these regulations are somewhat<br />
rudimentary [TPC, 1999].<br />
In U.S. federal regulations 10<br />
CFR 50 Appendix A, General Design<br />
Criterion 3 specifies the basic fire<br />
protection requirements for nuclear<br />
power plants [CFR, 2012]. For<br />
example, the design of the fire protection<br />
system must ensure that even in<br />
the event of damage of improper use,<br />
the safety performance would not be<br />
impaired. Fire protection policy based<br />
on defense-in-depth is used to protect<br />
the shutdown system as follows:<br />
1) preventing the occurrence of fires,<br />
2) ensuring the rapid detection, control,<br />
and extinguishing of fires that<br />
do occur, and<br />
3) ensuring the normal operation<br />
of the safe shutdown system if a<br />
fire cannot be extinguished [NCR,<br />
1975].<br />
95<br />
OPERATION AND NEW BUILD<br />
Operation and New Build<br />
The Application of Knowledge Management and TRIZ for solving the Safe Shutdown Capability in Case of Fire Alarms in Nuclear Power Plants ı Chia-Nan Wang, Hsin-Po Chen, Ming-Hsien Hsueh and Fong-Li Chin
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
OPERATION AND NEW BUILD 96<br />
In 10 CFR 50 Appendix R, Section<br />
III.G.1 are specified the fire protection<br />
requirements for the emergency<br />
shutdown of nuclear power plants:<br />
1. One train of systems necessary to<br />
achieve and maintain hot shutdown<br />
conditions from either<br />
the control room or emergency<br />
control station(s) is free of fire<br />
damage.<br />
2. Systems necessary to achieve and<br />
maintain cold shutdown from<br />
either the control room or emergency<br />
control station(s) can be<br />
repaired within 72 hours [NRC,<br />
2007].<br />
In 10 CFR 50 Appendix R, Section<br />
III.G.2 are outlined specific isolation<br />
requirements for redundant cables<br />
and safe shutdown systems within the<br />
same fire compartment: “Except as<br />
provided for in paragraph G.3 of this<br />
section, where cables or equipment,<br />
including associated non-safety<br />
circuits that could prevent operation<br />
or cause maloperation due to hot<br />
shorts, open circuits, or shorts to<br />
ground, of redundant trains of systems<br />
necessary to achieve and maintain hot<br />
shutdown conditions are located<br />
within the same fire area outside of<br />
primary containment, one of the<br />
following means of ensuring that<br />
one of the redundant trains is free<br />
of fire damage shall be provided.”<br />
10 CFR 50 Appendix R, Section<br />
III.G.3 specifies the situations in<br />
which fire compartments are required<br />
to have dedicated safe shutdown<br />
capabilities involving modification or<br />
replacement of dedicated cables and/<br />
or circuitry.<br />
Cables, systems and components<br />
should be independent of area, room,<br />
zone if the following conditions are<br />
met:<br />
1. Where the protection of systems<br />
whose function is required for hot<br />
shutdown does not satisfy the<br />
requirement of paragraph G.2 of<br />
this section; or<br />
2. Where redundant trains of systems<br />
required for hot shutdown located<br />
in the same fire area may be subject<br />
to damage from fire suppression<br />
activities or from the rupture or<br />
inadvertent operation of fire<br />
suppression systems.<br />
3. Furthermore, fire detection and a<br />
fixed fire suppression system shall<br />
be installed in the area, room, or<br />
zone.”<br />
Guidance IX of the NRC Information<br />
Notice 84-094 lists the minimum safe<br />
shutdown monitoring parameters<br />
accepted by the NRC [NRC Information<br />
Notice, 1984].<br />
NUREG-1852 presents the feasibility<br />
and reliability criteria [NUREG,<br />
2007] accepted by the NRC in the<br />
event that Operator Manual Actions<br />
(OMAs) are used to perform post-fire<br />
safe shutdown.<br />
The above fire protection regulations<br />
provide the parameters relevant<br />
to safe shutdown capabilities and<br />
fire protection. We compared these<br />
parameters with those of the nuclear<br />
power plant in our case study to<br />
identify problems associated with<br />
safe shutdown capabilities and fire protection.<br />
However, this is an enormous<br />
and complex task. Thus, we developed<br />
an innovative approach to achieve this<br />
using knowledge management in<br />
conjunction with TRIZ.<br />
3 Methodology<br />
This study sought to improve the safe<br />
shutdown performance of nuclear<br />
power plants in the event of fire.<br />
Knowledge management was first<br />
used to identify the factors essential<br />
to safe shutdown. We then sought<br />
to identify the factors that are not<br />
adequately addressed in US nuclear<br />
power regulations. Finally, TRIZ was<br />
used to guide the formulation of<br />
recommendations aimed at overcoming<br />
current regulatory shortcomings.<br />
3.1 Knowledge management<br />
and construction of database<br />
Knowledge management was organized<br />
into the following phases to<br />
define core knowledge and construct a<br />
database for research [Rosner et al.,<br />
1998].<br />
Phase 1: Progress from the macroscopic<br />
system level to the microscopic<br />
equipment level.<br />
Phase 2: Identify wiring associated<br />
with post-fire safe-shutdown.<br />
Phase 3: Conduct post-fire safe-shutdown<br />
circuit analysis [Debowski,<br />
2007].<br />
Phase 4: Establish post-fire hot shutdown<br />
path based on APP.R.<br />
Phase 5: Construct a distribution of<br />
post-fire safe hot shutdowns procedures<br />
throughout the plant.<br />
Phase 6: Establish basic fire prevention<br />
database [National Fire Protection<br />
Association, 2001].<br />
3.2 Application of TRIZ to<br />
improve safe shutdown<br />
system<br />
TRIZ is a highly reliable problemsolving<br />
method, which was developed<br />
by Altshuller et al. in his review of over<br />
300,000 patents between 1946 and<br />
1985 [Altshuller, 1999]. TRIZ is based<br />
on the concept of abstraction, taking<br />
an algorithmic approach to the invention<br />
of new systems and the refinement<br />
of old systems [Mann, 2007].<br />
In this study, we combined<br />
knowledge management and TRIZ<br />
in the development of a novel<br />
method by which to improve safe<br />
shutdown procedures, as follows<br />
(comp. Figure 1):<br />
1. Collect data pertaining to<br />
current conditions and existing<br />
designs.<br />
2. Formulate standards and definitions<br />
based on existing regulations<br />
related to post-fire safe<br />
shutdown.<br />
3.1. Define and clarify issues. If<br />
sufficient data is available, proceed<br />
to Step 4; otherwise, proceed<br />
to Step 3.2.<br />
3.2. Search available data and current<br />
regulations for designs that could<br />
be improved through knowledge<br />
management. Compare results<br />
with the safety conditions stipulated<br />
in current regulations, and<br />
then conduct enhancement<br />
analysis based on the following<br />
knowledge management techniques:<br />
(1) establish operating<br />
standards; (2) identify interdependent<br />
relationships between<br />
existing systems; (3) organize<br />
operational procedures; (4) set<br />
safe shutdown function codes;<br />
(5) establish safe shutdown path<br />
combinations; (6) compare results<br />
with regulation requirements;<br />
(7) identify all devices associated<br />
with post-fire safe shutdown<br />
(8) set operating status parameters;<br />
(9) compare results with<br />
corresponding wire/circuit design<br />
data of original equipment;<br />
(10) identify wires/circuits associated<br />
with post-fire safe shutdown;<br />
(11) conduct wire/circuit failure<br />
analysis; (12) compile results of<br />
wire/circuit analysis in the form<br />
of a database; (13) establish wire/<br />
circuit paths in fire zones. If<br />
level-by-level comparisons show<br />
that the existing system complies<br />
with regulations, then proceed<br />
to Step 6.<br />
4. Search through database of<br />
existing system for instances of<br />
mismatch with regulations. If the<br />
database does not meet safety<br />
requirements, then return to<br />
Step 1. If the database meets<br />
safety requirements, then perform<br />
an assessment of ...<br />
5. Determine whether non-compliant<br />
systems affect safe shutdown<br />
capabilities.<br />
Operation and New Build<br />
The Application of Knowledge Management and TRIZ for solving the Safe Shutdown Capability in Case of Fire Alarms in Nuclear Power Plants ı Chia-Nan Wang, Hsin-Po Chen, Ming-Hsien Hsueh and Fong-Li Chin
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
6. If the current safe shutdown<br />
capabilities meet or surpass those<br />
stipulated in the regulations, then<br />
proceed to Step 8. If the current<br />
safe shutdown capabilities do<br />
not meet those stipulated in the<br />
regulations, then proceed to<br />
Step 7.<br />
7. Use TRIZ to search for improvement<br />
methods, while taking into<br />
account construction costs and<br />
probable benefits.<br />
8. If the current status of the nuclear<br />
power plant complies with the<br />
basic safety conditions stipulated<br />
in the regulations, then it is<br />
assumed that the plant possesses<br />
satisfactory safe shutdown capability.<br />
4 Empirical results<br />
4.1 Application of knowledge<br />
management<br />
We selected a nuclear power plant for<br />
use as a case study. Fire compartments<br />
were drawn up according to the floor<br />
plan and final safety analysis report<br />
(FSAR) (Table 1). Most nuclear power<br />
plants include the following: containment<br />
or drywell building, reactor<br />
(auxiliary) building, turbine building,<br />
intake structure (screenhouse), fuel<br />
building, diesel generator building. In<br />
principle, if an area is enclosed by<br />
fire-shielding concrete walls, then<br />
smaller fire zones can be drawn up<br />
within the larger fire zone in order to<br />
differentiate between similar paths. In<br />
this case, the original fire compartment<br />
C101 includes numerous rooms.<br />
ESF 4.16KV SWGR ROOM A was designated<br />
fire compartment 5 in order to<br />
re-partition the space according to<br />
their function.<br />
Phase 1: Progress from the macroscopic<br />
system level to the microscopic<br />
equipment level.<br />
Step 1: Define the scope of the<br />
post-fire safe shutdown capacity.<br />
Shutdown objectives include the<br />
following: 1. reactivity control;<br />
2. reactor coolant makeup; 3. reactor<br />
heat removal; 4. process monitoring;<br />
5. supporting functions; 6. achieve hot<br />
Unit<br />
FL<br />
No.<br />
FL<br />
Code<br />
Factory<br />
building<br />
| | Tab. 1.<br />
Examples of partitioning fire compartment in nuclear power plant.<br />
| | Fig. 1.<br />
Application of knowledge management and TRIZ to improve post-fire safe shutdown performance.<br />
standby status and maintain systems<br />
required to (i) prevent fire damage,<br />
(ii) enable the power unit to last<br />
through hot standby status for over<br />
72 hours, and (iii) receive power<br />
from emergency power system;<br />
7. achieve cold shutdown status<br />
and maintain systems required to<br />
prevent fire damage. The above<br />
objectives do not cover the following:<br />
(1) seismic category I criteria,<br />
(2) single failure criteria, or (3) other<br />
plant accidents.<br />
Step 2: Define the core knowledge<br />
parameters of post-fire safe shutdown<br />
capacity.<br />
1) Establish map of interdependence<br />
among systems employed in<br />
post-fire safe shutdown. 2) Define<br />
operating procedures of post-fire safe<br />
shutdown systems and construct<br />
operational flowchart. 3) Define<br />
parameters of post-fire safe shutdown<br />
functions and construct function code<br />
list. 4) Identify function code combinations<br />
required for post-fire safe<br />
shutdown path and construct path<br />
combination table.<br />
Step 3: Refer to existing regulations<br />
NEI-0001 and RG1.189 of<br />
US–NRC to confirm that the post-fire<br />
safe shutdown and wire/circuit<br />
analysis methods are acceptable.<br />
First step: Determine Regulatory<br />
Requirements<br />
Space<br />
FL Name<br />
1 1 C101 CTRL 80' ESSENTIAL CHILLER ROOM A<br />
1 2 C101 CTRL 80' ESF 4.16KV SWGR ROOM A<br />
1 3 C101 CTRL 80' ESF SWGR ROOM A<br />
1 4 C1<strong>02</strong> CTRL 80' ESSENTIAL CHILLER ROOM B<br />
1 5 C1<strong>02</strong> CTRL 80' ESF 4.16KV SWGR ROOM B<br />
The primary regulations include<br />
10 CFR 50 Appendix A, General Criterion<br />
3, and 10 CFR 50 Appendix R.<br />
Second step: Determine SSD<br />
Functions, Systems, and Path<br />
This is meant to ensure that any<br />
single fire within any fire area in the<br />
nuclear power plant does not lead to<br />
incidents such as furnace core meltdown,<br />
loss of reactor cooling water, or<br />
damage to the primary containment<br />
structure. To achieve this objective,<br />
the safe shutdown functions of the<br />
reactor must first be confirmed and<br />
the existing system equipment and<br />
pipelines in the plant analyzed and<br />
combined to form a safe shutdown<br />
path as well as achieve and maintain<br />
the safe shutdown status of the power<br />
unit.<br />
Third step: Select Equipment<br />
Required for Post-Fire Safe shutdown<br />
This equipment is used for post-fire<br />
safe shutdown or to serve as a backup<br />
in the event of fire-induced malfunctions.<br />
Fourth step: Select Wires/Circuits<br />
for Post-Fire Safe shutdown<br />
These wires/circuits are used for<br />
post-fire safe shutdown or to serve as a<br />
backup in the event of fire-induced<br />
malfunctions<br />
Below are the basic assumptions<br />
used in the analysis of post-fire safe<br />
shutdown capacity:<br />
1. Only one fire occurs in the plant at<br />
any one time.<br />
2. In the event of loss of external<br />
power due to fire, systems can<br />
provide backup power for at least<br />
72 hours.<br />
3. The only equipment or system<br />
malfunctions are associated<br />
directly with the fire.<br />
4. After the safe shutdown of the<br />
power unit, there are no additional<br />
accidents due to plant design<br />
OPERATION AND NEW BUILD 97<br />
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<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
OPERATION AND NEW BUILD 98<br />
Drawing<br />
No.<br />
including (1) loss-of-coolant accidents<br />
(LOCA), (2) main steam line<br />
breaks (MSLB), (3) steam generator<br />
tube ruptures (SGTR), or (4)<br />
control rod ejection accidents<br />
(REA.)<br />
5. Any wires or equipment in the area<br />
of a fire that are not protected by<br />
fire wrap are burned, unless the<br />
results fire disaster analysis prove<br />
otherwise.<br />
6. Fire-induced wire/circuit damage<br />
can lead to open circuits, short<br />
circuits, hot shorts, and shorts to<br />
ground.<br />
7. The valves, pipelines, tanks, or<br />
incombustible instrument wires<br />
affected by the fire do not cause<br />
damage to the pressure boundary.<br />
8. Despite fire damage to instruments,<br />
the pressure boundaries<br />
of fluids within them are not<br />
damaged.<br />
9. Motor-operated valves do not malfunction<br />
due to fire damage to<br />
power wires, but they may malfunction<br />
following fire damage to<br />
control circuits.<br />
10. During post-fire safe shutdown,<br />
power units may be controlled<br />
manually using existing equipment,<br />
as long as the fire does not<br />
directly hinder such operations.<br />
The scope of the core knowledge<br />
relating to post-fire safe shutdown<br />
capacity can be clearly defined and<br />
verified based on the analytical<br />
methods proposed in NEI 00-01 Rev. 2<br />
and the target performance of safe<br />
shutdown capacity.<br />
Step 4: Establish inventory of<br />
post-fire safe shutdown equipment.<br />
Determine the specifications of<br />
post-fire safe shutdown equipment<br />
(Table 2): 1. attributes, 2. operating<br />
status, and 3. path parameters [NFPA,<br />
2001].<br />
Function Description<br />
Old System<br />
Code<br />
SSD<br />
Code<br />
1 RCS BB B1/B2<br />
2 RCS-ACCUM ISO BH B1/B2<br />
3 CVCS HHSI BG B5/B6<br />
4 CVCS HHSI SUP BG BS56<br />
5 SIS HHSI BH B7/B8<br />
6 CVCS RCP BG C5/C6<br />
| | Tab. 2.<br />
Post-fire safe shutdown system parameters for case study.<br />
Phase 2: Identify wire/circuits<br />
associated with post-fire alarm safe<br />
shutdown.<br />
Step 1: Identify wires and circuits<br />
associated used with post-fire safe<br />
shutdown equipment.<br />
Using the original design data of<br />
the plant, list every power wire and<br />
control wire associated with the<br />
post-fire safe shutdown equipment.<br />
Step 2: Determine the specifications<br />
of all wire/circuits associated<br />
with post-fire safe shutdown. Set the<br />
parameters of operating status,<br />
equipment attributes, and the safe<br />
shutdown paths to which they belong.<br />
Step 3: Refer to the existing database,<br />
control wiring diagram (CWD),<br />
and control logic diagram (CLD) to<br />
identify the control wires associated<br />
with each piece of equipment.<br />
Step 4: Compile an inventory of<br />
wires associated with post-fire safe<br />
shutdown (NEI, 2009).<br />
A series post-fire safe shutdown<br />
path (Code: HSD-P1):<br />
(A1+A3)+(B1+B3+B5+B7+B9)+<br />
(D1+E1+F1+G1+H1+I1+J1+K1+<br />
L1+M1+N1+P1+S1+U1+V1+<br />
W1+X1+Y1.)<br />
B series post-fire safe shutdown<br />
path (Code: HSD-P2):<br />
(A2+A4)+(B2+B4+B6+B8+B10)+<br />
(D2+E2+F2+G2+H2+I2+J2+K2+<br />
L2+M2+N2+P2+S2+U2+V2+<br />
W2+X2+Y2)<br />
Taking the plant from operating<br />
to hot shutdown requires that the<br />
equipment listed above be operational.<br />
These devices must also be<br />
included in independent paths<br />
HSD-P2 or HSD-P1.<br />
Example of system parameters<br />
(Table 2) and shutdown path: The<br />
power for the motor driven auxiliary<br />
feed water pump (A-1M-AL-P017) in<br />
auxiliary feed water system of Series A<br />
(system parameter B3) is supplied by<br />
Class 1E 4.16kV Bus A-1E-PB-S01 (PB<br />
system). In post-fire safe shutdown<br />
operation mode, this bus is powered<br />
by the emergency diesel generator in<br />
Series A (system parameter D1). Thus,<br />
a supply of lubricating oil and a fuel<br />
(KJ system) must be available for the<br />
emergency diesel generator. At the<br />
same time, it is essential that the 125V<br />
DC electrical system (PK system)<br />
provide power to the control panel<br />
of the emergency diesel generator<br />
A-1J-ZD-P001. The emergency diesel<br />
generator is uses a jacket water-cooler<br />
A-1M-KJ-X072 running off of a<br />
seawater system (EF system); the<br />
power for the seawater pump A-1M-<br />
EF-P103, P104 is provided by the<br />
4.16kV bus A-1E-PB-S01 (PB system.)<br />
This is an example of the analysis used<br />
to establish the interdependence of<br />
systems within a given post-fire safe<br />
shutdown path.<br />
Phase 3: Establish an inventory of<br />
wire/circuits associated with post-fire<br />
safe shutdown.<br />
Step 1: Use the wire/circuit inventory<br />
established in previous phase to<br />
conduct effect analysis of fire-induced<br />
wire/circuit failures. Analyze fire- induced<br />
circuit failures (power, control,<br />
instrument) associated with each piece<br />
of equipment, based on inventory of<br />
equipment used in post-fire safe shutdown.<br />
These wire/circuits can be<br />
divided into two categories: those<br />
necessary to post-fire hot shutdown<br />
and those necessary to post-fire safe<br />
shutdown. Single-line diagrams, CLDs,<br />
and CWDs of post-fire safe shutdown<br />
equipment in the original design are<br />
used to investigate fire-induced circuit<br />
failures, as follows:<br />
(1) Categorization of wires required<br />
for post-fire hot shutdown:<br />
a. Power and control wires required<br />
for manual operation of equipment<br />
used in post-fire hot shutdowns<br />
b. Power and signal wires for instruments<br />
used in process monitoring<br />
during post-fire hot shutdown<br />
c. Wires that could cause the malfunction<br />
(through fire-induced<br />
circuit failure) of equipment required<br />
for post-fire hot shutdowns<br />
d. Wires that could cause the malfunction<br />
of components (through<br />
fire-induced circuit failure) in<br />
high/low pressure system<br />
(2) Categorization of wires required<br />
for post-fire safe shutdown:<br />
a. Power and control wires required<br />
for manual operation of equipment<br />
used in post-fire cold shutdowns<br />
b. Wires that could cause the malfunction<br />
(through fire-induced<br />
circuit failure) of equipment required<br />
for cold shutdowns<br />
c. Wires that could cause the malfunction<br />
of components crucial to<br />
shutdowns (through fire-induced<br />
circuit failure)<br />
Fire-induced circuit-failure parameters<br />
were established as follows:<br />
1) fire-induced circuit-failure equipment,<br />
2) operating status parameters,<br />
3) fire-induced circuit-failure parameters,<br />
and 4) wire/circuit attribute<br />
parameters.<br />
Step 2: Use the circuit-failure<br />
parameters to construct a table for the<br />
analysis of circuits used in post-fire<br />
safe shutdown.<br />
Effect analysis of fire-induced<br />
circuit failures associated with the<br />
post-fire safe shutdown equipment,<br />
including open circuits, short circuits,<br />
hot shorts, and shorts to ground (445<br />
items in total). This analysis produced<br />
5,149 results.<br />
Operation and New Build<br />
The Application of Knowledge Management and TRIZ for solving the Safe Shutdown Capability in Case of Fire Alarms in Nuclear Power Plants ı Chia-Nan Wang, Hsin-Po Chen, Ming-Hsien Hsueh and Fong-Li Chin
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
Cable No.<br />
SSD<br />
Code<br />
SSD Equipment<br />
No.<br />
| | Tab. 3.<br />
Examples of post-fire safe shutdown cable paths.<br />
After referring to the parameters<br />
associated with post-fire safe shutdown<br />
equipment in the previous step,<br />
the fire-induced circuit-failure effect<br />
parameters and wire/circuit attributes<br />
were compiled into a post-fire<br />
safe shutdown circuit analysis table.<br />
Four types of parameter were<br />
required: 1) fire-induced circuitfailure<br />
equipment, 2) operating status<br />
parameters, 3) fire-induced circuitfailure<br />
parameters, and 4) wire/<br />
circuit attribute parameters.<br />
Step 3: The regulations stipulate<br />
special requirements for the wiring<br />
involved in hot shutdowns; therefore,<br />
the scope of the core knowledge was<br />
defined as the wires associated with<br />
post-fire hot shutdowns.<br />
Step 4: We establish an inventory<br />
of the wires involved in post-fire safe<br />
hot shutdown.<br />
Phase 4: Establish a path associated<br />
with post-fire hot shutdown for<br />
use as a reference based on the special<br />
requirements in APP.R with regard to<br />
wires associated with hot shutdown.<br />
Step 1: Define the scope of core<br />
knowledge and the wires associated<br />
with post-fire hot shutdown.<br />
Step 2: Set the relevant wire/<br />
circuit parameters, equipment operating<br />
status parameters, equipment<br />
attribute parameters, and safe shutdown<br />
path parameters.<br />
Step 3: Refer to the existing wire/<br />
circuit layout program SETROUTE in<br />
the original design to derive the circuit<br />
layout. The fire zones will need to be<br />
updated, as the original layout<br />
program uses the old fire zones. To<br />
facilitate analysis, the fire zones,<br />
equipment specifications, safe shutdown<br />
paths, and operating status<br />
parameters must be added to the database<br />
of the wire/circuit layout.<br />
Step 4: Establish an inventory of<br />
wire/circuit paths involved in post-fire<br />
safe shutdown.<br />
Step 5: Establish the post-fire<br />
alarm safe hot shutdown path form<br />
(Table 3). Compile a report of wire/<br />
circuit paths involved in post-fire safe<br />
hot shutdown. The nuclear power<br />
plant in the case study has two power<br />
units. Unit 1 contains 1,189 wires and<br />
17,379 items, whereas Unit 2 contains<br />
SSD<br />
Path<br />
SSD Cable<br />
Type<br />
1,184 wires and 17,233 items. Thus,<br />
there are 2,373 wires associated with<br />
post-fire safe hot shutdown. The<br />
organization of the report is based on<br />
the number system used for the safe<br />
shutdown equipment, the attribute<br />
categorization of the wires, their<br />
origin and destination, the numbering<br />
of the wire/circuit raceways, and the<br />
fire zones through which they pass.<br />
Phase 5: Construct the distribution<br />
of post-fire safe hot shutdowns<br />
throughout the entire plant.<br />
Step 1: Define the scope of the core<br />
knowledge and the post-fire safe hot<br />
shutdown path.<br />
Step 2: Set the fire zones to their<br />
corresponding parameters.<br />
Step 3: Based on the wire/circuit<br />
layout program, identify the fire zones<br />
through which each wire passes.<br />
Step 4: Establish the distribution<br />
of the post-fire hot-shutdown function<br />
codes and replot the post-fire hotshutdown<br />
tray routing diagram in<br />
order to obtain an overview of the safe<br />
hot shutdown capacity throughout<br />
the entire plant.<br />
Example: Series A is presented in<br />
red and series B in green. The safe<br />
shutdown cable path in the original<br />
SETROUTE and corresponding function<br />
code are used to obtain the safe<br />
shutdown path and function code of<br />
each fire containment zone (Table 4).<br />
Phase 6: Establish a database of<br />
items pertaining to basic fire prevention.<br />
Basic fire prevention includes a<br />
wide range of items: (1) basic data of<br />
fire zones, (2) firefighting equipment<br />
in fire zones, (3) fire dampers, (4) fire<br />
doors, (5) combustion load of fire<br />
zones, (6) list of fire zones adjacent to<br />
each fire zone (7), inventory of heat<br />
generated by all combustible items.<br />
4.2 Application of TRIZ<br />
The proposed knowledge management<br />
approach revealed that fire<br />
compartments 1 and 17 do not comply<br />
with some regulations [10 CFR 50.48<br />
APP.R]. Specifically, Wires involved in<br />
post-fire safe hot shutdown must not<br />
pass through the same fire compartment<br />
without the implementation of<br />
suitable fire protection measures. The<br />
FROM No. Raceway No. FZ<br />
B1EEFHCC8SA H2 B-EF-HV203 HSD-P2 HSD-S 1JZJP061E-F 1 B1EZJG2TSRH 20<br />
B1EEFHCC8SA H2 B-EF-HV203 HSD-P2 HSD-S 1JZJP061E-F 2 B1EZJG2TUAG 20<br />
B1EEFHCC8SA H2 B-EF-HV203 HSD-P2 HSD-S 1JZJP061E-F 3 B1EZJG2TUAF 20<br />
FL FL No. HSD Path No. SSD Path<br />
1 C101 D1 HSD-P1<br />
1 C101 H1 HSD-P1<br />
1 C101 I2 HSD-P2<br />
1 C101 K2 HSD-P2<br />
| | Tab. 4.<br />
Example distribution list of fire alarm safe hot shutdown function codes.<br />
| | Fig. 2.<br />
Qualitative analysis model for identification<br />
of problem.<br />
| | Fig. 3.<br />
Standard solutions for eliminating harmful<br />
effects of fire.<br />
passage of series A and B wires<br />
through FZ 1 and FZ 17 renders this<br />
area vulnerable to fire damage [Hua<br />
and Yang, 2006]. The structure of this<br />
problem is modeled in Figure 2.<br />
Figure 3 presents a qualitative<br />
field model illustrating the association<br />
between completeness and damage,<br />
revealing the first problems to be<br />
eliminated or controlled in a standard<br />
solution.<br />
In this case, the designers used<br />
XPE/Cl.S.PE cables with heat<br />
resistance of 90 °C. Their Q value<br />
(Bench-Scale HRR per Unit Floor<br />
Area) is 204 kW/m 2 , which means<br />
that they are classified as safe, even in<br />
OPERATION AND NEW BUILD 99<br />
Operation and New Build<br />
The Application of Knowledge Management and TRIZ for solving the Safe Shutdown Capability in Case of Fire Alarms in Nuclear Power Plants ı Chia-Nan Wang, Hsin-Po Chen, Ming-Hsien Hsueh and Fong-Li Chin
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
OPERATION AND NEW BUILD 100<br />
| | Fig. 4.<br />
Parameter attribute problem model for fire damage to the cable.<br />
the event of fire; i.e., they have a<br />
high ignition point and low release<br />
of heat. The conductivity of the cable<br />
helps to maintain its structural integrity<br />
[NUREG, 2010]. The first<br />
physical contradiction appears when<br />
the temperature exceeds 100 °C.<br />
There are four steps that can be taken<br />
to combat this: spatial separation,<br />
temporal separation, condition separation,<br />
and separation of system<br />
levels. These are used to perform<br />
separation of fire areas, cable burn<br />
time, burning conditions, and safe<br />
shutdown system levels (Figure 4).<br />
All cables must remain reliable<br />
along their entire length in order to<br />
ensure a safe shutdown. The fact that<br />
fire damage can compromise<br />
reli ability leads to the second technical<br />
contradiction.<br />
We constructed a 39X39 contradiction<br />
matrix to be compared with<br />
the 40 Inventive Principles based on<br />
the problem model established on<br />
structural attributes and parameter<br />
attributes. Comparison of temperature<br />
and reliability resulted in the<br />
selection of the following inventive<br />
principles:<br />
# 3: Local quality<br />
#10: Preliminary action<br />
#19: Periodic action<br />
#35: Parameter changes<br />
A panel of experts decided to disregard<br />
Principle #19. Principle #35<br />
was not applicable because the cables<br />
had already been laid. Principles #3<br />
and #10 were implemented for<br />
reasons outlined in the following:<br />
Inventive principle #3 (local quality):<br />
3a. Change an object’s structure from<br />
uniform to non-uniform, change<br />
an external environment (or<br />
external influence) from uniform<br />
to non-uniform.<br />
3b. Make each part of an object<br />
function in conditions most<br />
suitable to its operation.<br />
3c. Make each part of an object fulfill a<br />
different and useful function.<br />
Improvement requirements and<br />
feasible methods<br />
(1) Cables from Series A and B should<br />
be separated by at least 20 feet.<br />
(2) Built-in discrete fire detection<br />
systems should be included in all<br />
areas. In the original design, FZ 1<br />
and FZ 17 each had one feedback<br />
system; however, they are now<br />
segmented into a feedback loop for<br />
each area [Generic Letters, 1983].<br />
(3) Install close-spaced, open-head<br />
sprinklers. According to GL 83-33,<br />
Position 2: “In many plant areas,<br />
the erection of physical barriers<br />
between redundant shutdown<br />
systems is precluded by the location<br />
of cable trays, HVAC ducts and<br />
other plant features. In such situations,<br />
the staff has accepted, in<br />
concept, the use of an automatic<br />
fire suppression system which<br />
No.<br />
Cable<br />
No.<br />
SSD<br />
Code<br />
Cable<br />
Code<br />
SSD<br />
Equipment No.<br />
SSD<br />
Path<br />
SSD<br />
Cable Type<br />
Raceway<br />
No.<br />
Rway<br />
Code<br />
1 B1EAPHBC2XA K2 EE6 B-AP-LT201 HSD-P2 HSD-S B1EZJF4TXBA WC<br />
2 B1EBNHAC2XA K2 EE6 B-BNLT961 HSD-P2 HSD-S B1EZJF4TXBA WC<br />
3 B1EEFHAC2XA H2 EE6 B-EF-PT201 HSD-P2 HSD-S B1EZJF4TXBA WC<br />
4 B1EEFHAC2XB H2 EE6 B-EF-PT2<strong>02</strong> HSD-P2 HSD-S B1EZJF4TXBA WC<br />
5 B1EEFHCC3EA H2 71M3 B-EF-P105 HSD-P2 HSD-S B1EZJF4TEBA SC<br />
6 B1EEFHCC3EB H2 71M B-EF-P105 HSD-P2 HSD-S B1EZJF4TEBA SC<br />
7 B1EEFHCC4EA H2 71M3 B-EF-P106 HSD-P2 HSD-S B1EZJF4TEBA SC<br />
8 B1EKJHBC3LA D2 938 B-KJ-P147 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
9 B1EKJHBC4LA D2 938 B-KJ-P148 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
10 BIEPGHHCEHH E2 91I3 B-1E-PG-S01-07 HSD-P2 HSD-S B1EZJF4TIBA SA<br />
11 B1EPGHHCEHJ E2 91I3 B-1E-PG-S01-07 HSD-P2 HSD-S B1EZJF4TIBA SA<br />
12 B1EEFHBCBSB H2 939 B-EF-HV230 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
13 B1EEFHBCBSD H2 939 B-EF-HV230 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
14 B1EEFHBCBSE H2 939 B-EF-HV230 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
15 B1EEFHBCJSA H2 C77 B-EF-HV206 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
16 B1EEFHCC8SA H2 C27 B-EF-HV203 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
17 B1EEFHCC8SB H2 C27 B-EF-HV203 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
18 B1EEFHCC8SC H2 C27 B-EF-HV203 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
19 B1EEFHCC9SA H2 C27 B-EF-HV222 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
20 B1EEFHCC9SB H2 C27 B-EF-HV222 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
21 B1EEFHCC9SC H2 C27 B-EF-HV222 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
22 B1EEFHCCASA H2 C77 B-EF-HV221 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
| | Tab. 5.<br />
Parameter attribute problem model for fire damage to the cable.<br />
Operation and New Build<br />
The Application of Knowledge Management and TRIZ for solving the Safe Shutdown Capability in Case of Fire Alarms in Nuclear Power Plants ı Chia-Nan Wang, Hsin-Po Chen, Ming-Hsien Hsueh and Fong-Li Chin
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
Advertisement<br />
discharges a “water curtain” across<br />
the boundary areas separating the<br />
redundant systems. The staff's<br />
present position is that such systems<br />
should feature close-spaced,<br />
open-head sprinklers with water<br />
discharge initiated by tripping a<br />
deluge valve activated by crosszoned<br />
smoke detectors.” Installation<br />
of a “water curtain” partition<br />
within the fire compartment<br />
ensured that both paths were safe<br />
for post-fire hot shutdown.<br />
(4) Install fire separation walls. Specifications:<br />
1. Fire resistance of<br />
3 hours. 2. Extending from wall to<br />
wall and from floor to ceiling.<br />
3. Fire door with a 3-hour rating to<br />
facilitate access by personnel.<br />
4. Air ducts that pass through the<br />
fire separation wall. A fire damper<br />
with a 3-hour rating must be<br />
installed within the section that<br />
passes through the fire separation<br />
wall. 5. A sleeve must be added to<br />
all piping that penetrates the fire<br />
separation wall. The sleeve must<br />
be sealed using fire-resistant<br />
material with a rating of 3 h. 6. The<br />
cable net passing through the fire<br />
separation wall must be filled with<br />
fire-resistant materials with a<br />
rating of 3 h [Generic Letters,<br />
1986]. The post-fire hot shutdown<br />
cable for FZ 17 runs through an<br />
aisle; therefore, fire separation<br />
walls are feasible only in FZ 1.<br />
The definitions and improvement<br />
plans associated with inventive<br />
principle #10 are as follows:<br />
10a: Perform all modifications in<br />
advance. Rearrange cables (relatively<br />
low cost.)<br />
10b: Install items or systems in<br />
advance to ensure that they are<br />
ready when and where that may<br />
be.<br />
FZ 1 contains mostly Series A cables<br />
as well as 22 Series B cables. The<br />
post-fire hot shutdown cable list<br />
( Table 5) revealed that 11 of the<br />
cables (number 1-11) can be re-laid<br />
along new paths, such that only 11<br />
cables (number 12-22) from Series B<br />
remain within FZ 1. At this point 10b<br />
No.<br />
SSD<br />
Equipment No.<br />
Status<br />
9. Symposium zur<br />
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radioaktiver Abfälle<br />
Vorbereitung auf KONRAD –<br />
Wege zum G2-Gebinde<br />
18. – 19. April <strong>2018</strong> in<br />
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• KFK – Herausforderung aus Sicht eines<br />
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• Endlager Konrad – Baufortschritt und<br />
Stand der sicherheitstechnischen<br />
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• Aspekte der Endlagerungsbedingungen<br />
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• Vorgehensweisen bei der stofflichen<br />
Produktkontrolle<br />
• Optimierte Prüfung von Antragsunterlagen<br />
Das detaillierte Programm finden Sie in Kürze<br />
unter: www.tuev-nord.de/tk-era<br />
Organisation:<br />
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E-Mail: mlangmann@tuev-nord.de<br />
Telefon: 040 8557-2046<br />
OPERATION AND NEW BUILD 101<br />
1 B-EF-HV203 ON<br />
2 B-EF-HV206 ON<br />
3 B-EF-HV221 ON<br />
4 B-EF-HV222 OFF<br />
5 B-EF-HV230 OFF<br />
| | Tab. 6.<br />
Valve states in hot shutdown mode.<br />
Operation and New Build<br />
The Application of Knowledge Management and TRIZ for solving the Safe Shutdown Capability in Case of Fire Alarms in Nuclear Power Plants ı Chia-Nan Wang, Hsin-Po Chen, Ming-Hsien Hsueh and Fong-Li Chin
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
OPERATION AND NEW BUILD 1<strong>02</strong><br />
can be used for OMA for manual<br />
disconnection or operations.<br />
To prevent equipment malfunction<br />
due to fire-induced cable damage, a<br />
fire alarm in FZ 1W signals the control<br />
room to initiate the first safe shutdown<br />
path using Series A cables.<br />
Similarly, a fire alarm in FZ 1E signals<br />
the control room to initiate the second<br />
safe shutdown path using Series B<br />
cables. On-duty staff must take the<br />
actions presented in Table 6.<br />
FZ 17 contains mainly Series B<br />
cables as well as 11 Series A cables.<br />
The post-fire hot shutdown cable list<br />
(Table 7) revealed there is no way to<br />
re-route the cable paths. At this point<br />
10b can be used for OMA for manual<br />
disconnection or operations.<br />
A fire alarm in FZ 17W signals the<br />
control room to initiate the first safe<br />
No.<br />
| | Fig. 5.<br />
Conformity to regulations in chart form.<br />
No. Cable No. SSD<br />
Code<br />
SSD<br />
Equipment No.<br />
Status<br />
1 B-EF-HV203 ON<br />
2 B-EF-HV206 ON<br />
3 B-EF-HV221 ON<br />
4 B-EF-HV222 OFF<br />
5 B-EF-HV230 OFF<br />
| | Tab. 8.<br />
Valve states in hot shutdown mode.<br />
Cable<br />
Code<br />
SSD Equipment<br />
No.<br />
SSD<br />
Path<br />
shutdown path using Series A cables.<br />
A fire alarm in FZ 17E signals the<br />
control room to initiate the second<br />
safe shutdown path using B cables.<br />
On-duty staff must take the actions<br />
presented in Table 8.<br />
The application of TRIZ requires<br />
that the following conditions be<br />
satisfied: At least one of the wire series<br />
has avoided fire damage. For the sake<br />
of simplicity, we adopted two inventive<br />
principles: finding local properties<br />
and taking preliminary actions.<br />
Nuclear power regulation 10 CFR<br />
50.48 APP.R stipulates that any wiring<br />
essential to post-fire hot shutdowns<br />
that passes through the same fire zone<br />
require sufficient shielding to protect<br />
them from fire for at least three h.<br />
They must also be separated at least<br />
20 ft, and automatic fire detection<br />
and extinguishing systems must be<br />
installed in the fire zone in question.<br />
All wiring is expected to comply<br />
with these regulations; however, prior<br />
to modifications based on the proposed<br />
method, 22 of the wires in<br />
Series B were non-compliant. This<br />
situation could not be foreseen without<br />
integration of 850,000 pieces of<br />
path data via knowledge management.<br />
Among the 22 wires, 11 were<br />
re-laid and within a fire compartment,<br />
thereby reducing the number of<br />
non-compliant wires to 11. According<br />
to the principle of preliminary action,<br />
the remaining 11 wires were deemed<br />
not to affect post-fire hot shutdown<br />
performance; therefore, even these 11<br />
wires can be said to comply with<br />
regulations.<br />
Regulations stipulate that the<br />
control room or emergency control<br />
station be equipped with a series of<br />
hot shutdown systems capable of<br />
maintaining hot shutdown conditions<br />
in the event of a fire in Fire Zones 1<br />
and/or 17.<br />
SSD<br />
Cable Type<br />
Raceway<br />
No.<br />
1 B1EEFHBCBSB H2 939 B-EF-HV230 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
2 B1EEFHBCBSD H2 939 B-EF-HV230 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
3 B1EEFHBCBSE H2 939 B-EF-HV230 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
4 B1EEFHBCJSA H2 C77 B-EF-HV206 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
5 B1EEFHCC8SA H2 C27 B-EF-HV203 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
6 B1EEFHCC8SB H2 C27 B-EF-HV203 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
7 B1EEFHCC8SC H2 C27 B-EF-HV203 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
8 B1EEFHCC9SA H2 C27 B-EF-HV222 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
9 B1EEFHCC9SB H2 C27 B-EF-HV222 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
10 B1EEFHCC9SC H2 C27 B-EF-HV222 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
11 B1EEFHCCASA H2 C77 B-EF-HV221 HSD-P2 HSD-S B1EZJF4TPBA SE<br />
| | Tab. 7.<br />
Series A cables in fire compartment 17 for safe hot shutdown.<br />
Rway<br />
Code<br />
Fire compartments capable of<br />
withstanding fire for three hours were<br />
installed between post-fire safe hot<br />
shutdown wires. The wires were<br />
horizontally separated by at least 20 ft<br />
and automatic fire detection and<br />
extinguishing systems were installed.<br />
Following these improvements in Fire<br />
Zones 1 and 17, the post-fire safe hot<br />
shutdown wires were in full compliance<br />
with regulations (Figure 5).<br />
Number of cables that do not<br />
comply with regulations ≠ Estimated<br />
number of cables that do not comply<br />
with regulations = “Do not comply<br />
with regulations”<br />
Number of cables that do not<br />
comply with regulations = Estimated<br />
number of cables that do not comply<br />
with regulations = “Comply with<br />
regulations”<br />
Number of non-complaint cables in<br />
case study nuclear power plant = 0<br />
5 Conclusions<br />
This study applied TRIZ and<br />
knowledge management to an actual<br />
nuclear power plant in order to<br />
bring the facility up to regulatory<br />
minimums. Problems were identified<br />
using hierarchy analysis in conjunction<br />
with knowledge management for<br />
the construction of a database. We<br />
then identified elements that failed to<br />
meet current regulations. TRIZ was<br />
used to identify optimal solutions in<br />
order to minimize the costs involved<br />
in making improvements to existing<br />
nuclear power plants.<br />
The database of wires and circuits<br />
essential to post-fire safe shutdown<br />
operations enables operators to<br />
identify affected systems and decide<br />
whether immediate isolation is<br />
required. The implementation of fire<br />
zones makes it easy to determine<br />
whether a zone lies along a safe<br />
shutdown path. The proposed method<br />
Operation and New Build<br />
The Application of Knowledge Management and TRIZ for solving the Safe Shutdown Capability in Case of Fire Alarms in Nuclear Power Plants ı Chia-Nan Wang, Hsin-Po Chen, Ming-Hsien Hsueh and Fong-Li Chin
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
is able to accurately identify zones<br />
requiring improvement for fire prevention<br />
or for other safety concerns. Previous<br />
regulatory evaluations determined<br />
only the degree of compliance;<br />
i.e., they gave no indication of whether<br />
a safe shutdown could actually be<br />
achieved. The proposed method helps<br />
to ensure that safe shutdown can be<br />
achieved, based on the safety requirements<br />
stipulated in existing regulations.<br />
Safe shutdown capability can<br />
be used as a criterion by which to<br />
identify the elements that cannot<br />
feasibly conform to regulations, such<br />
as areas where automatic fire detection<br />
and extinguishing systems cannot<br />
be installed. TRIZ is an innovative<br />
approach to problem-solving. It provides<br />
a range of possibilities by which<br />
to solve problems and the results are<br />
easily compiled to facilitate training<br />
procedures. Few existing studies on<br />
nuclear power plants apply directly to<br />
real-world cases. Knowledge management<br />
methods enable the construction<br />
of a knowledge base, thereby providing<br />
a means by which to integrate<br />
implicit and explicit knowledge. Its<br />
systematic integration of analysis and<br />
comparison data provide valuable a<br />
reference to practitioners in the field.<br />
Parameter settings based on<br />
current regulatory conditions and<br />
the use of knowledge management<br />
models enables quicker and more<br />
precise identification of the improvements<br />
required for compliance with<br />
existing regulations. A fire prevention<br />
database provides a valuable reference<br />
for the assessment of fire safety.<br />
Subsequent tasks include developing<br />
fire models and automatic analysis<br />
instruments based on fire dynamics,<br />
fire load, and fire risk probability,<br />
which all require such databases. The<br />
basic fire prevention database in this<br />
study meets the basic requirements<br />
for fire analysis and can be used for<br />
future studies of post-fire phenomena<br />
in nuclear power plants. The procedure<br />
outlined in this study provides a<br />
model for safety assessment of current<br />
nuclear power plants as well as a<br />
complete research framework for<br />
other fire-related research in nuclear<br />
power plants and even other types of<br />
safety measures. The nuclear power<br />
plant studied in this paper features<br />
three-loop pressurized water reactors.<br />
Therefore the details of the research<br />
procedure related to the water<br />
reactors are not necessarily applicable<br />
to other types of reactor. Data<br />
collection, analysis, and comparison<br />
would have to be performed anew<br />
to confirm its applicability.<br />
References<br />
| | Altshuller, G., Shulyak, L., Rodman, S.,<br />
1999. The Innovation Algorithm: TRIZ,<br />
Systematic Innovation and Technical<br />
Creativity. Technical Innovation Ctr.:<br />
Worcester, MA.<br />
| | Debowski, S., 2007. Knowledge<br />
Management. Wiley India Pvt. Ltd.<br />
| | Generic Letters GL 83-33, Position 2,<br />
1983. Water Curtain, October, 1983.<br />
| | Generic Letters GL 86-10, Position 3.6.2,<br />
1986. Fire Stop, April, 1986.(1.) NRC<br />
BTP APCSB 9.5-1 App. A , (1976)<br />
Fire Protection guide for Nuclear Power<br />
Plants, May, 1986.<br />
| | Hua, Z., Yang, J., Coulibaly, S., Zhang, B.,<br />
2006. Integration TRIZ with problemsolving<br />
tools: a literature review from<br />
1995 to 2006. International Journal of<br />
Business Innovation and Research 1:<br />
111-128.<br />
| | Information Notice 84-09, 1984.<br />
Lessons Learned from NRC Inspections<br />
of Fire Protection Safe Shutdown<br />
Systems (10 CFR 50, Appendix R).<br />
| | Mann, D., 2007. Hands-on Systematic<br />
Innovation. IFR Press: Clevedon, UK.<br />
| | National Fire Protection Association<br />
805, Performance-based Standard for<br />
Fire Protection for Light Water Reactor<br />
Electric Generating Plants, 2001 Edition.<br />
| | NEI 00-01, Rev.2, 2009. Guidance for<br />
Post Fire Safe Shut Down Circuit Analysis.<br />
| | NFPA805 National Fire Protection<br />
Association 805, Performance-based<br />
Standard for Fire Protection for Light<br />
Water Reactor Electric Generating<br />
Plants, 2001 Edition.<br />
| | NRC Branch Technical Position (BTP)<br />
9.5-1, 1981. Guidelines For Fire<br />
Protection For Nuclear Power Plants,<br />
CMEB, July 1981.<br />
| | NRC BTP APCSB 9.5-1 App. A , 1976.<br />
Fire Protection guide for Nuclear Power<br />
Plants.<br />
| | NRC Standard Review Plan 9.5-1, 1975.<br />
Fire Protection Program, November,<br />
1975.<br />
| | NRC, 1979. 10 CFR 50 Appendix R to<br />
Part 50 – Fire Protection Program For<br />
Nuclear Power Facilities Operating Prior<br />
To January 1.<br />
| | NRC, 1984. Information Notice 84-094<br />
Guidance IX.<br />
| | NRC, 2007. RG 1.189, Rev. 2 Section<br />
5.3, Fire Protection of Safe-Shutdown<br />
Capabilities.<br />
| | NRC, 2012. 10 CFR 50 Appendix A to<br />
Part 50, General Design Criterion 3.<br />
| | NUREG-1852, 2007. Demonstrating the<br />
Feasibility and Reliability of Operator<br />
Manual Actions in Response to Fire,<br />
Final Report, October, 2007.<br />
| | NUREG-1924, 2010. Electric Raceway<br />
Fire Barrier Systems in U.S. Nuclear.<br />
| | Rosner, D., Grote, B., Hartman, K,<br />
Hofling, B, Guericke, O., 1998. From<br />
natural language documents to<br />
sharable product knowledge: a<br />
knowledge engineering approach. In:<br />
Borghoff U.M., Pareschi, R. (Eds.),<br />
Information technology for knowledge<br />
management, pp. 35–51, Springer<br />
Verlag.<br />
| | Society of Fire Protection Engineers,<br />
2003. SFPE Hand Book.<br />
| | TPC Maanshan Nuclear Power Plant,<br />
1999. Final Safety Analyze Report.<br />
| | TRIZ: A New Approach to Innovative<br />
Engineering and Problem Solving, 1996<br />
AME Annual Conference in Milwaukee,<br />
WI, November 5-8.<br />
| | USNRC Generic Letter 77-<strong>02</strong>, 1977. Fire<br />
Protection Functional Responsibilities,<br />
Administrative Control and Quality<br />
Assurance.<br />
Authors<br />
Chia-Nan Wang<br />
Hsin-Po Chen<br />
Fong-Li Chin<br />
Ming-Hsien Hsueh<br />
Department of Industrial<br />
Engineering and Management<br />
National Kaohsiung University<br />
of Applied Sciences<br />
No.415, Jiangong Rd., Sanmin Dist.,<br />
Kaohsiung City 807<br />
Taiwan, China<br />
Department of Industrial<br />
Engineering and Management<br />
National Kaohsiung University<br />
of Applied Sciences<br />
No.415, Jiangong Rd., Sanmin Dist.,<br />
Kaohsiung City 807<br />
Taiwan, China<br />
OPERATION AND NEW BUILD 103<br />
Operation and New Build<br />
The Application of Knowledge Management and TRIZ for solving the Safe Shutdown Capability in Case of Fire Alarms in Nuclear Power Plants ı Chia-Nan Wang, Hsin-Po Chen, Ming-Hsien Hsueh and Fong-Li Chin
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
104<br />
DECOMMISSIONING AND WASTE MANAGEMENT<br />
Corrosion Processes of Alloyed Steels<br />
in Salt Solutions<br />
Bernhard Kienzler<br />
Introduction For many years, in Germany POLLUX canisters were considered as reference concept for spent<br />
nuclear fuel disposal casks. The cask consists of the shielding cask with a screwed-in lid and the inner cask with bolted<br />
primary and welded secondary lid. The spent fuel should be inserted in the final disposal cask in bins. The cylindrical<br />
wall and bottom of the inner cask consist of fine-grained steel 15 MnNi 6.3. The thickness of the cylindrical wall was<br />
designed according to the mechanical and shielding requirements and was 160 mm thick. The primary lid of the inner<br />
cask was also made of fine-grained steel. This lid was designed to keep the sealing function prior to and during the<br />
welding of the secondary lid. A plate made of neutron-moderating and absorbing materials (carbon/boron mixture)<br />
was attached to the primary lid. The secondary lid is designed as a welded lid. The base body of the shielding cask<br />
consisted of ductile cast iron (GGG 40). The wall thickness was designed according to the requirements for the shielding<br />
and was 265 mm thick. The weight of the POLLUX cask was 65 Mg [1]. The whole POLLUX cask consisted of actively<br />
corroding steels.<br />
The corrosion behavior of the POLLUX<br />
materials in salt solution for temperatures<br />
up to 200°C were investigated<br />
[2]. Both materials showed high corrosion<br />
rates especially at elevated<br />
temperatures and frequently the question<br />
was asked why not using alloyed<br />
steels. In fact, alloyed steels are developed<br />
to be corrosion resistant, and the<br />
steels are widely used especially for<br />
corrosion-resistant applications.<br />
Alloyed steels such as stainless<br />
steels do not readily corrode, rust or<br />
stain in contact with water as finegrained<br />
or cast iron steels. However,<br />
the alloyed steels are not fully stainproof<br />
in low-oxygen or high-salinity<br />
environments. There are various<br />
grades and surface finishes of stainless<br />
steel to suit the environment the<br />
alloy must endure. Stainless steel is<br />
used where both the properties of<br />
steel and corrosion resistance are<br />
required.<br />
Stainless steels differ from carbon<br />
steel by the amount of chromium<br />
present. Unprotected carbon steel<br />
rusts when exposed to air and<br />
moisture. The iron oxide film has<br />
lower density than steel, the film<br />
expands and tends to flake and fall<br />
away. In comparison, stainless steels<br />
contain sufficient chromium to<br />
undergo passivation, forming an inert<br />
film of chromium oxide on the surface.<br />
This layer prevents further corrosion<br />
by blocking oxygen diffusion to the<br />
steel surface and stops corrosion from<br />
spreading into the bulk of the metal.<br />
Passivation occurs only if the proportion<br />
of chromium is high enough<br />
and oxygen is present.<br />
In the scope of corrosion studies<br />
of high-level waste canister materials,<br />
the corrosion behavior of several<br />
alloyed materials was investigated.<br />
The materials comprised nickel based<br />
alloys (Hastelloy C22 and C4), and<br />
chromium-nickel steels. Furthermore,<br />
titanium alloys and copper-nickel<br />
alloys were taken into the investigations.<br />
These alloys are not covered in<br />
this contribution.<br />
The recommendations of the<br />
German High-Level Waste Commission<br />
[3] are reflected in the German law for<br />
amendment of the site selection law<br />
(passed by the German Parliament,<br />
March 23, 2017 [4]). Especially the<br />
maximum temperature condition has<br />
been changed. The maximum temperature<br />
at the canister surfaces is now<br />
limited to 100 °C, and the retrievability<br />
of the wastes during the operational<br />
phase of the disposal and the recoverability<br />
of the wastes for a period of 500<br />
years is need to be taken into account.<br />
Corrosion mechanisms<br />
of alloyed steels<br />
The corrosion resistance of stainless<br />
steel (Cr-Ni steel) known under<br />
atmospheric conditions depends on<br />
the chromium content of the alloy.<br />
Chromium leads to the formation of a<br />
passive layer, the so-called chromium<br />
oxide skin, which spontaneously<br />
forms in air and protects the material<br />
underneath from corrosion. By<br />
alloying different chromium and<br />
molybdenum fractions, the corrosion<br />
resistance can be adjusted to the<br />
environmental conditions. The low<br />
corrosion rates of Cr-Ni steels are due<br />
to the build-up of passive layers (oxide<br />
layers) on the surface, which are<br />
re-established under the conditions of<br />
low-concentrated solutions.<br />
The stability of container materials<br />
in a deep underground disposal is<br />
influenced by various uniform and<br />
local corrosion processes. These<br />
processes are controlled by the local<br />
geochemical conditions, in particular<br />
pH, redox potential and chloride<br />
concentration. Iron and steels are not<br />
thermodynamically stable in contact<br />
with water or saline solution. A<br />
number of different corrosion processes<br />
are described depending on a<br />
variety of factors [5]. For metals, two<br />
types of corrosion occur: general and<br />
localized corrosion.<br />
• General or uniform corrosion<br />
results in a relatively uniform mass<br />
loss over the entire area of the<br />
sample. General corrosion effects<br />
are predictable. Cast irons and<br />
steels corrode uniformly when<br />
exposed to open atmospheres, soils<br />
and natural waters as well as in salt<br />
solutions.<br />
• Localized corrosion occurs at discrete<br />
sites on the metal surface.<br />
The areas immediately adjacent to<br />
the localized corrosion normally<br />
corrode to a much lesser extent.<br />
These types of corrosion are less<br />
common in atmospheric exposure<br />
than in immersion exposures.<br />
Corrosion activity at localized<br />
corrosion sites may vary with<br />
changes of the water composition,<br />
defects in passivation layers,<br />
changes in contaminants or<br />
pollutants, changes in the electrolyte<br />
and by formation of<br />
galvanic cells. The predominant<br />
forms of localized corrosion are<br />
pitting and crevice corrosion.<br />
• Pitting corrosion is especially<br />
prevalent in metals that form a<br />
protective oxide layer. Pitting<br />
can be initiated on an open,<br />
freely-exposed surface or at<br />
imperfections in the passivation<br />
layer. Deep, even fully penetrating<br />
pits can develop with<br />
Decommissioning and Waste Management<br />
Corrosion Processes of Alloyed Steels in Salt Solutions ı Bernhard Kienzler
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
only a relatively small amount<br />
of metal loss. Pitting can occur<br />
isolated or as group of pits<br />
which may coalesce to form a<br />
large area of damage.<br />
• Crevice corrosion occurs in<br />
crevices where the environment<br />
differs from the surrounding<br />
bulk environment. The different<br />
environments result in<br />
corrosion because of differences<br />
in concentration (e.g.,<br />
oxygen, pH, and ferric ions). If<br />
there is an oxygen concentration<br />
difference, corrosion will<br />
proceed at crevices where less<br />
oxygen is available than in the<br />
environment surrounding the<br />
crevice. Crevices are formed<br />
when two surfaces are in<br />
proximity to one another, such<br />
as when two metal surfaces are<br />
in close contact.<br />
• Contact (galvanic) corrosion<br />
occur when different metals are<br />
in contact in a common electrolyte.<br />
At current flows between<br />
the two metals, the less noble<br />
metal (the anode) corrodes at a<br />
faster rate than would have<br />
occurred if the metals were not<br />
in contact. In this case, the rate<br />
of corrosion depends on the<br />
relative areas of the metals in<br />
contact and the composition<br />
(conductivity) of the electrolyte.<br />
• Stress corrosion cracking<br />
(SCC) requires the simultaneous<br />
presence of tensile<br />
stresses (effect of external loads<br />
or welding / bending) and<br />
specific environmental factors.<br />
• Intergranular attack is caused<br />
by carbon diffusion to the grain<br />
boundaries and precipitation as<br />
chromium carbide. This effect<br />
removes chromium from the<br />
metal phase (solid solution)<br />
leaving a lower chromium<br />
content adjacent to the grain<br />
boundaries.<br />
Especially in environments with high<br />
chloride concentrations, chloride<br />
promotes the breakdown of the oxide<br />
layer. In the presence of chloride ions,<br />
oxygen can be displaced by chloride<br />
ions in the oxide layer of the passivated<br />
metal. The addition of further<br />
chloride ions results in a region which<br />
is no longer protected by the oxide<br />
layer. This site now offers an attack<br />
point for further corrosion. Under<br />
favorable circumstances, a so-called<br />
re-passivation may occur: the chloride<br />
ion is displaced again by oxygen, and<br />
the protective oxide layer is “repaired”<br />
again. Otherwise, the pitting corrosion<br />
continues. The rate of displacement<br />
of oxygen by chloride in the<br />
passivation layer is the measure of the<br />
incubation period for the occurrence<br />
of local corrosion processes. The<br />
following mechanisms effect pitting<br />
corrosion [6]:<br />
• The dissolved oxygen concentration<br />
outside of the pit is considerably<br />
higher than in the hole. The<br />
low oxygen concentration in the<br />
pit hinders re-passivation of the<br />
metal.<br />
• The small pit forms an anode, the<br />
remaining surface represents the<br />
cathode. The corrosion rate is<br />
determined by the ratio of the<br />
cathode to anode area.<br />
• The metal dissolves according<br />
Me n+ + H 2 O + k MeOH (n-1)+ +<br />
H + , reducing the pH.<br />
• Critical potential must exceed a<br />
certain critical potential value. In<br />
salt solution, the critical potential<br />
is defined by E pit = A + B log [Cl − ]<br />
with Cl − is the bulk chloride<br />
concentration. B is generally in<br />
the range 60-90 mV [7]. Critical<br />
pitting potentials (E pit ) of 1.4301<br />
Cr-Ni steel (type 304, UNS S30400)<br />
are reported by Yashiro et al [8] as<br />
a function of temperature (373 K<br />
to 523 K) and chloride (Cl − )<br />
concentration (0.01 to 2 mol/kg-<br />
H 2 O). Steady polarization tests<br />
were performed at discrete intervals<br />
around Epit. Results were<br />
expressed by E pit = A − B log [Cl − ].<br />
In regard to temperature dependency,<br />
the constant A decreased<br />
with temperature, while B was<br />
almost constant up to 448 K.<br />
• In the presence of Cl − , the dissolved<br />
metal in the pit reacts with<br />
chloride forming iron chlorides<br />
which hydrolyses (FeCl 2 +H 2 O vk<br />
FeClOH + Cl − + H + ) and reduce<br />
the pH.<br />
The actual water consumption for<br />
pitting corrosion is substantially lower<br />
than in the case of uniform surface<br />
corrosion of unalloyed steels. Carbon<br />
steels also shows a passivation in the<br />
alkaline environment, e.g. at pH > 12<br />
in concrete constructions [9].<br />
In contrast to alloyed steels,<br />
unalloyed carbon steels do not build<br />
up a protective layer under low or<br />
slightly basic pH conditions, since<br />
the alloying element chromium is<br />
missing. Under acidic to basic pH<br />
conditions voluminous iron oxides /<br />
iron hydroxides are formed, which<br />
generally do not adhere to the underlying<br />
material. Therefore, the steel is<br />
not protected but the oxidation is<br />
maintained under the influence of<br />
moisture and oxygen. This reaction<br />
observed in the unalloyed steels is<br />
referred to as an active corrosion<br />
process in which iron reacts to iron<br />
oxide/hydroxide. Numerous experiments<br />
have shown that the active<br />
corrosion of the unalloyed steels is<br />
uniform and at a largely constant rate<br />
[10–16]. This behavior allows predicting<br />
the mass loss or thickness<br />
reduction of the disposal cask to a<br />
certain degree.<br />
The corrosion experiments reported<br />
here were performed in salt<br />
solutions. Under reducing conditions<br />
as they prevail in a deep geological<br />
disposal, the corrosion process of<br />
carbon steel consumes water and<br />
generates hydrogen. During the corrosion<br />
process, dissolved iron reacts<br />
with the aqueous medium forming<br />
ferrous hydroxides with divalent iron<br />
(Fe II ). At 7 < pH < 9, the observed<br />
solid corrosion products are magnetite<br />
(Fe 3 O 4 ) and amorphous iron<br />
hydroxides. At sufficiently low redox<br />
potentials (absence of oxygen) in<br />
chloride solutions, Cl − ions react with<br />
amorphous iron hydroxides forming<br />
the reaction product “green rusts”.<br />
This compound has the formula<br />
[Fe II 3Fe III (OH) 8 ]Cl×H 2 O and can be<br />
formed at [Cl − ]/[OH − ] > 1 [17]. It<br />
consists of both Fe II and trivalent iron<br />
(Fe III ). In contact with oxygen, green<br />
rust transforms quickly to magnetite.<br />
In the presence of Mg-rich brines,<br />
(Fe,Mg)(OH) 2 and Fe(OH) 2 Cl compounds<br />
were found and characterized<br />
[18].<br />
Materials and methods<br />
When the corrosion experiments were<br />
started, the boundary conditions for<br />
the research on container materials<br />
for highly radioactive waste resulted<br />
from the requirements defined by<br />
pouring the molten highly radioactive<br />
glass directly into the canister, apply<br />
the necessary welding and decontamination<br />
of the containers and by<br />
the requirement for transport, interim<br />
storage and final disposal. For the<br />
POLLUX canister, the influence of the<br />
production and sealing of a final<br />
storage canister was considered, and<br />
U-shaped samples, welded samples<br />
using different welding procedures, as<br />
well as contact samples were prepared<br />
for the experiments. In particular, to<br />
assess the influence of the welding on<br />
the corrosion processes, different<br />
treatments of the samples were<br />
applied, including the delivery state,<br />
heat-treated samples, welded and<br />
subsequently heat-treated samples.<br />
DECOMMISSIONING AND WASTE MANAGEMENT 105<br />
Decommissioning and Waste Management<br />
Corrosion Processes of Alloyed Steels in Salt Solutions ı Bernhard Kienzler
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
DECOMMISSIONING AND WASTE MANAGEMENT 106<br />
Material<br />
Material<br />
description<br />
A comprehensive description of the<br />
sample shape and treatment has been<br />
published [19]. Further experiments<br />
included contact samples where<br />
different steels were screwed together<br />
in close contact and corrosion tests<br />
under γ irradiation. The whole suite of<br />
steels under investigations ale listed in<br />
Table 1.<br />
Two different sample types were<br />
produced to test the materials for<br />
mass loss, pitting corrosion, crack<br />
corrosion and stress corrosion<br />
Material<br />
number<br />
Density<br />
g/cm 3<br />
Ni based alloys Hastelloy C4 Ni Mo 16 Cr 16 Ti 2.4610 8.669<br />
Ti alloys Titan – Palladium Ti 99.7 – Pd<br />
Ti 99.7 - Pd EG<br />
Fe based alloys Fine-grained steel FStE 255<br />
TStE 460<br />
15 Mn Ni 6.3<br />
DC 01 / St 12<br />
ST 37-2<br />
Cr-Ni steel<br />
Cu alloys<br />
Nodular cast steel<br />
Ni-Resist D2<br />
Ni-Resist D4<br />
Nirosta<br />
GGG 40.3<br />
GGG-Ni Cr 20.2<br />
GGG-Ni Si Cr 30.55<br />
X2CrNi19-11<br />
Cu.99<br />
Cu-Ni 70/30<br />
Cu-Ni 90/10<br />
Ni alloys Nickel 99.9<br />
Ni/Cu 70/30<br />
| | Tab. 1.<br />
Metal alloys for construction of waste canisters under investigation at KIT-INE.<br />
3.7<strong>02</strong>5<br />
3.7035<br />
1.0566<br />
1.8915<br />
1.6210<br />
1.0330<br />
1.0038<br />
0.7043<br />
0.7660<br />
0.7680<br />
1.4833<br />
1.4306<br />
4.0000<br />
4.7000<br />
4.9000<br />
2.4068<br />
2.4360<br />
4.593<br />
4.593<br />
7.814<br />
7.671<br />
7.512<br />
7.85<br />
7.856<br />
6.955<br />
7.36<br />
7.596<br />
8.<strong>02</strong>2<br />
7.956<br />
9.198<br />
8.866<br />
8.998<br />
8.48<br />
8.51<br />
cracking (SCC). For the determination<br />
of the mass loss, sheet metal specimens<br />
with the dimensions 40 mm ×<br />
20 mm were cut in the respectively<br />
available sheet thicknesses. The mass<br />
loss was determined only in the case<br />
of samples in the delivery condition.<br />
The susceptibility to pitting corrosion<br />
as well as the susceptibility to crack<br />
corrosion could be assessed also.<br />
The Ni-Resist steels have been<br />
included in the investigation program<br />
because these steels are specified for<br />
handling salt solutions such as sea<br />
water. Lower uniform corrosion rates<br />
were expected as in the case of fine<br />
grained steel. After the exposure time,<br />
the samples were recovered from the<br />
corrosion medium and the specimens<br />
were cleaned from the adhering salts<br />
and corrosion products by pickling in<br />
suitable solutions according to ASTM<br />
guidelines [20]. Then the specimens<br />
were cleaned in alcohol and examined<br />
for general and local corrosions as<br />
well as for stress corrosion cracking.<br />
The general corrosion (integral corrosion<br />
rate) was calculated from the<br />
integral weight losses determined by<br />
gravimetry and from the respective<br />
material densities. The specimens<br />
were examined for local corrosion and<br />
stress corrosion cracking by microscopic<br />
evaluation and with the help of<br />
metallographic cross-sections, measurements<br />
of pit depths and surface<br />
profiles.<br />
Results and discussion<br />
General corrosion<br />
Due to the fact that localized corrosion<br />
processes are observed in the<br />
experiments, the mass loss rate is used<br />
for comparisons. The general corrosion<br />
rate relies on uniform corrosion<br />
of the surfaces and is not considered<br />
reasonably for alloyed steel. Figure 1<br />
and Figure 2 show the mass loss and<br />
the corresponding mass loss rates for<br />
a) mass loss<br />
b) mass loss rate<br />
| | Fig. 1.<br />
Measured mass loss and mass loss rates of Hastelloy in MgCl 2 -rich (red) and NaCl solution (blue) as function of time at various temperatures.<br />
a) mass loss<br />
b) mass loss rate<br />
| | Fig. 2.<br />
Measured mass loss and mass loss rates of Cr-Ni steels (1.4306 and 1.4388) in MgCl 2 -rich (red) and NaCl solution (blue) as function of time at 150 °C.<br />
Decommissioning and Waste Management<br />
Corrosion Processes of Alloyed Steels in Salt Solutions ı Bernhard Kienzler
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DECOMMISSIONING AND WASTE MANAGEMENT 108<br />
a) mass loss<br />
b) mass loss rate<br />
| | Fig. 3.<br />
Measured mass loss and mass loss rates of fine-grained steel (1.6210) in MgCl 2 -rich (red) and NaCl solution (blue) as function of time at 150 °C.<br />
Hastelloy and for the two Cr-Ni steels.<br />
The Hastelloy experiments covered a<br />
temperature range between 90 °C and<br />
170 °C, whereas the CR-NI steels were<br />
investigated at 150 °C, only.<br />
For Hastelloy, all mass loss rates<br />
were found below 12 g m -2 yr. -1 showing<br />
no distinct time dependence. For<br />
the experiments with Cr-Ni steels, the<br />
initial mass loss rates decreased and<br />
remained for the long term below<br />
15 g m -2 yr. -1 . The effect of the solution<br />
type on the mass loss rates for Cr-Ni<br />
steels was not significant. Also, the<br />
differences of the mass loss and mass<br />
loss rates between 1.4306 and 1.4833<br />
steels were marginal. Concerning the<br />
temperature effect of the general<br />
corrosion of Hastelloy, relatively high<br />
mass losses were found at 90°C after<br />
676 days. At higher temperatures, the<br />
exposure period remained below 500<br />
days. The reason for the increased<br />
mass losses could be explained by<br />
crevice corrosion of the Hastelloy C22<br />
in MgCl 2 rich solution showing pit<br />
depths of about 200 µm. The scatter<br />
of mass losses is correlated to local<br />
corrosion processes.<br />
For comparison, the mass loss and<br />
mass loss rates of the fine-grained<br />
steel 1.6210 is shown in Figure 3. In<br />
this case, the mass loss rates were by a<br />
factor of 50 higher in comparison to<br />
the Cr-Ni steel in NaCl solutions and<br />
by a factor about 100 higher in MgCl 2<br />
solution after about 500 days (150 °C).<br />
The uniform mass loss rates of<br />
the Ni-Resist steels were found in<br />
the range of the Cr-Ni steels at<br />
20 ± 7 g m 2 yr. 1 for steel 0.7660<br />
and 12 ± 9 g m -2 yr. -1 for 0.7680,<br />
respectively. These values are also<br />
significantly lower in comparison to<br />
the fine-grained steel 1.6210.<br />
| | Fig. 4.<br />
Crevice corrosion in Hastelloy C22 after 676<br />
days in MgCl 2 rich solution at 90 °C showing<br />
depths of about 200 µm.<br />
Local corrosion phenomena<br />
The breakdown of passivity (the<br />
breaching of the protective barrier<br />
provided by the passive film) initiates<br />
the most damaging kinds of corrosion,<br />
the localized forms of corrosion,<br />
pitting, crevice corrosion, intergranular<br />
attack, and stress corrosion. The<br />
induction period for pitting corrosion<br />
starts with the initiation of the breakdown<br />
process by the introduction of<br />
breakdown conditions and ends when<br />
the localized corrosion density begins<br />
to rise. Unfortunately, electrochemical<br />
corrosion studies were applied<br />
only for carbon steel and the influence<br />
of chemical species in brines have<br />
been investigated [21]. For this<br />
reason, corrosion potential for pitting<br />
corrosion have not been determined<br />
for the investigated alloyed steels.<br />
In brine media, localized corrosion<br />
has been investigated over the complete<br />
range of chloride concentrations.<br />
The Cl- concentration, however,<br />
is not as critical as pH and temperature,<br />
since the attack can occur at any<br />
concentration over the minimum<br />
value. Factors such as incubation<br />
time, severity, and frequency of<br />
occurrence can be influenced by the<br />
concentration.<br />
Localized corrosion was observed<br />
for all alloyed steels. In the case of<br />
Hastelloy C22, the first pits occurred<br />
after 275 days in the MgCl 2 rich<br />
solution at 90 °C. These pits had<br />
depths of about 10 µm. After 552<br />
days, the depths increased to 20 µm<br />
and after 676 days, a pit’s depth of<br />
200 µm was found in a crevice. In the<br />
MgCl 2 solution 2, even deeper pits<br />
were detected. In NaCl solution, after<br />
552 days, the pit’s depth amounted to<br />
16 µm.<br />
The average pit depths as function<br />
of time in the steels 1.4306 and 1.4833<br />
are shown in Figure 5.<br />
In contrast to the observations<br />
for Hastelloy, the depths of the pits<br />
were significantly deeper after about<br />
3 months. The pits showed relative<br />
a) Steel 1.4306 at 150°C<br />
| | Fig. 5.<br />
Average pit depths determined in untreated Cr-Ni steels as function of time.<br />
b) Steel 1.4833 at 150°C<br />
Decommissioning and Waste Management<br />
Corrosion Processes of Alloyed Steels in Salt Solutions ı Bernhard Kienzler
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
a) Stress corrosion cracking in the heat<br />
affected zone of a welding seam:<br />
TSS Experiment at Asse salt mine<br />
temperature: 180 °C<br />
Duration: about 11 years.<br />
| | Fig. 6.<br />
Localized corrosion phenomena of steel 1.4306: Stress corrosion cracking along grain boundaries.<br />
high depth variations. The immersion<br />
tests were terminated after about 500<br />
days, therefore an increase in the pit’s<br />
depths as determined in the case of<br />
Hastelloy was not observed. The<br />
average pit depth of both steel was<br />
found in the range of 30 to 40 µm.<br />
The steels 1.4306 and 1.4833<br />
showed significant stress corrosion<br />
cracking at 150 °C (tests at 90 °C were<br />
not performed). Figure 6 shows polished<br />
micrographs of steel 1.4306<br />
specimen in contact with dry rock salt<br />
(a) and immersed in NaCl solution.<br />
Localized corrosion was found in<br />
both cases, even in the almost dry<br />
con ditions established in the TSS<br />
experiment performed in the Asse salt<br />
mine [22]. The penetration depths<br />
of the cracks were measured in<br />
the mm range. Contact samples in<br />
MgCl 2 solution showed even more<br />
pronounced stress corrosion cracking<br />
[2].<br />
With Hastelloy C4 corrosion tests<br />
under γ-irradiation of 10 Gy/h were<br />
performed (fuel element storage<br />
pool at Dido test reactor at the<br />
Research Center Juelich). Different<br />
types of samples were examined:<br />
plane samples as delivered, plane<br />
samples with removed oxide layer<br />
on the surface, U-shaped welded<br />
samples, crevice samples, and samples<br />
| | Fig. 7.<br />
Intergranular corrosion in a Ni-Resist D4<br />
sample after 776 days in MgCl 2 solution<br />
at 90 °C.<br />
b) Stress corrosion cracking of a plane<br />
specimen of steel 1.4306 after 422 days<br />
in NaCl solution at 150°C.<br />
with different welding procedures<br />
such as tungsten inert gas welding<br />
(TIG) or electron beam welding (EB).<br />
Significant deviation of the observed<br />
mass losses in comparison to test without<br />
irradiation were not found.<br />
Almost all Ni-Resist steel samples<br />
showed intergranular corrosion effects<br />
(Figure 7). These referred to samples<br />
as delivered and to crevice samples.<br />
Summary and conclusions<br />
The results of the corrosion experiments<br />
with Cr-Ni steels, Hastelloy and<br />
the Ni-Resist materials revealed a<br />
significantly lower general corrosion<br />
rate (mass loss rate) in comparison to<br />
the fine-grained steels. On the other<br />
hand, these materials were subdued<br />
to localized corrosion processes such<br />
as pitting corrosion, crevice corrosion,<br />
intergranular corrosion and stress<br />
corrosion cracking. The local corrosion<br />
processes were enhanced in<br />
welded or in contact specimen. In<br />
many cases, the localized corrosion<br />
phenomena were found only after<br />
certain incubation periods. Especially<br />
in the case of Hastelloy, the incubation<br />
period was about 9 months at 90 °C in<br />
MgCl 2 solution and the pitting corrosion<br />
rate was relatively high. Stress<br />
corrosion cracking by intergranular<br />
corrosion of the Cr-Ni steels penetrated<br />
deep into the materials. Intergranular<br />
corrosion was also found in<br />
the Ni-Resist steels.<br />
As a consequence of the occurrence<br />
of localized corrosion processes<br />
as well as the unpredictable incubation<br />
times of these processes, one<br />
might understand the decision to<br />
apply uniformly corroding steels for<br />
waste canisters, even if the general<br />
corrosion rate would be by a factor up<br />
to 1,000 higher.<br />
The mass loss is proportional to the<br />
hydrogen produced under reducing<br />
conditions in a deep disposal. A<br />
POLLUX cask has a surface area of<br />
about 30 m 2 . Under extreme conditions,<br />
15 kg of steel could be corroded<br />
per year in NaCl solution, forming<br />
360 mol H 2 per year (8 m 3 standard<br />
conditions). Hydrogen keeps a reducing<br />
environment, however, by<br />
increasing pressure it acts as driving<br />
force for gas, solution and contaminant<br />
transport. Internationally efforts<br />
are undertaken to reduce the potential<br />
amount of hydrogen produced by<br />
corrosion phenomena.<br />
Based on the measurements<br />
reported in this contribution, Cr-Ni<br />
steels seem not to provide a reasonable<br />
solution for a long-lived stable<br />
waste package. Even, if the hydrogen<br />
production is reduced, the long-term<br />
sealing function of these steels is<br />
unclear. Under the almost dry condition<br />
of the in-situ experiment (TSS)<br />
in the Asse mine, stress corrosion<br />
cracking in the heat affected zone of<br />
a welding seam of Cr-Ni steel was<br />
observed after 11 years at 180 °C.<br />
Acknowledgment<br />
The corrosion studies of canister<br />
materials for heat producing wastes<br />
cover exclusively the research performed<br />
by Dr. Emmanuel Smailos and<br />
his working group. Until his retirement<br />
in 2004, Dr. Smailos was responsible<br />
for the corrosion studies of<br />
various materials at the Institute for<br />
Nuclear Waste Disposal (INE).<br />
References<br />
[1] H. Lahr, H.-O. Willax, and H. Spilker,<br />
Conditioning of spent fuel for interim<br />
and final storagein the pilote conditioning<br />
plant (PKA) at Gorleben, in<br />
International Symposium on Storage of<br />
Spent Fuel from Power Reactors,<br />
Vienna, Austria, 9-13 November 1998,<br />
1998.<br />
[2] E. Smailos and B. Fiehn, Korrosionsuntersuchungen<br />
an der Werkstoffkombination<br />
des POLLUX-Behaelters<br />
zur direkten Endlagerung abgebrannter<br />
Brennelemente in Steinsalz formationen,<br />
Forschungszentrum Karlsruhe, KfK-<br />
4552, 1989.<br />
[3] Kommission Lagerung hoch radioaktiver<br />
Abfallstoffe, ABSCHLUSSBERICHT:<br />
Verantwortung für die Zukunft: Ein faires<br />
und transparentes Verfahren für die<br />
Auswahl eines nationalen Endlagerstandortes,<br />
Geschäftsstelle der<br />
Kommission Lagerung hoch radioaktiver<br />
Abfallstoffe, K-Drs 268, 2016.<br />
[4] Gesetz zur Fortentwicklung des<br />
Gesetzes zur Suche und Auswahl eines<br />
Standortes für ein Endlager für Wärme<br />
entwickelnde radioaktive Abfälle und<br />
anderer Gesetze, 2017.<br />
[5] Uhligs corrosion handbook, 3 rd ed<br />
( Online-Ausg.) ed. Hoboken, N.J: Wiley,<br />
2011.<br />
DECOMMISSIONING AND WASTE MANAGEMENT 109<br />
Decommissioning and Waste Management<br />
Corrosion Processes of Alloyed Steels in Salt Solutions ı Bernhard Kienzler
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
DECOMMISSIONING AND WASTE MANAGEMENT 110<br />
[6] R. Newman, Pitting Corrosion of Metals,<br />
Electrochem. Soc. Interface Vol. 19,<br />
pp. 33-38, 2010<br />
[7] J. R. Galvele, Transport processes and<br />
the mechanism of pitting of metals,<br />
J. Electrochem. Soc. , Vol. 123,<br />
pp. 464-474 1976.<br />
[8] H. Yashiro, K. Tanno, S. Koshiyama, and<br />
K. Akashi, Critical Pitting Potentials for<br />
Type 304 Stainless Steel in High-<br />
Temperature Chloride Solutions<br />
Corrosion, Vol. 52, pp. 109-114, 1996.<br />
[9] George R. Brubaker and P. B. P. Phipps,<br />
Corrosion chemistry, Washington, D.C.:<br />
American Chemical Society, 1979.<br />
[10] E. Smailos, W. .Schwarzkopf, R. Köster,<br />
and K. H. Gruenthaler, Advanced<br />
corrosion studies on selected packaging<br />
materials for disposal of HLW canisters<br />
in rock salt, in Corrosion Problems<br />
Related to Nuclear Waste Disposal:<br />
A Working Party Report, European<br />
Federation of Corrosion, Ed., ed: The<br />
Institute of Materials, 1992, pp. 23-31.<br />
[11] E. Smailos, W. Schwarzkopf , B. Kienzler,<br />
and K. R., Corrosion of Carbon-Steel<br />
Containers for Heat-Generating Nuclear<br />
Waste in Brine Environments Relevant<br />
for a Rock-Salt Repository, in Scientific<br />
Basis for Nuclear Waste Management:<br />
Proc.of the 15th Internat.Symp.,<br />
Strasbourg, November 4-7, 1991, 1992,<br />
pp. 399-406.<br />
[12] E. Smailos, Corrosion of high-level<br />
waste packaging materials in disposal<br />
relevant brines, Nuclear Technology,<br />
Vol. 104, pp. 343-350, 1993.<br />
[13] E. Smailos, I. Azkarate, J. A. Gago,<br />
P. van Iseghem, B. Kursten, and<br />
T. McMenamin, Corrosion on metallic<br />
HLW container materials, in Fourth<br />
European Conference on Management<br />
and Disposal of Radioactive Waste,<br />
1997, pp. 209-223.<br />
[14] E. Smailos, A. Martínez-Esparza,<br />
B. Kursten, G. Marx, and I. Azkarate.,<br />
Corrosion evaluation of metallic<br />
materials for long-lived HLW/spent<br />
fuel disposal containers, Forschungszentrum<br />
Karlsruhe, FZKA 6285, 1999.<br />
[15] E. Smailos, M. A. Cunado, I. Azkarate,<br />
B. Kursten, and G. Marx, Long-term<br />
performance of candidate materials for<br />
HLW/spent fuel disposal containers,<br />
Forschungszentrum Karlsruhe, Wissenschaftliche<br />
Berichte, FZKA-6809, 2003.<br />
[16] E. Smailos, Influence of gamma<br />
radiation on the corrosion of carbon<br />
steel, heat-generating nuclear waste<br />
packaging in salt brines, IAEA, Wien<br />
IAEA TECDOC-1316 Effects of Radiaton<br />
and Environmental Factors on the<br />
Durability of Materials in Spent Fuel<br />
Storage and Disposal, 1995.<br />
[17] A. Raharinaivo, G. Arliguie,<br />
T. Chaussadent, G. Grimaldi, V. Pollet,<br />
and G. Taché, La corrosion et la<br />
protection des aciers dans le béton,<br />
Paris: Presses de l'École Nationale des<br />
Ponts et Chaussées, 1998.<br />
[18] B. Grambow, E. Smailos, H. Geckeis,<br />
R. Müller, and H. Hentschel, Sorption<br />
and reduction of uranium(VI) on iron<br />
corrosion products under reducing saline<br />
conditions, Radiochimica Acta, Vol.<br />
74, pp. 149-154, 1996.<br />
[19] E. Smailos, R. Köster, and<br />
W. Schwarzkopf, Korrosionsuntersuchungen<br />
an Verpackungsmaterialien<br />
für Hochaktive Abfälle, European Appl.<br />
Res. Rept. - Nucl. Sci. Technol., Vol. 5,<br />
pp. 175-222, 1983.<br />
[20] ASTM G 1- 72, Recommended Practice<br />
for Preparing, Cleaning and Evaluation<br />
of Corrosion Test Specimens, Annual<br />
Book of ASTM Standards, Vol. Part 10,<br />
p. 489, 1974.<br />
[21] A. M. Farvaque-Bera and E. Smailos,<br />
Electrochemical Corrosion Studies on a<br />
Seleted Carbon Steel for Application in<br />
Nuclear Waste Disposal Containers:<br />
Influence of Chemical Species in Brines<br />
on Corrosion, Kernforschungszentrum<br />
Karlsruhe, KfK-5354, 1994.<br />
[22] W. Bechthold, E. Smailos,<br />
S. Heusermann, W. Bollingfehr,<br />
B. B. Sabet, T. Rothfuchs, P. Kamlot,<br />
J. G. Olivella, and F. D. Hansen,<br />
Back filling and sealing of underground<br />
repositories for radioactive waste in<br />
salt (Bambus II project). Final report,<br />
European Commission, EUR-20621-EN,<br />
2004.<br />
Author<br />
Dr. Bernhard Kienzler<br />
Karlsruhe Institute of<br />
Technology (KIT)<br />
Institut für Nukleare<br />
Entsorgung (INE)<br />
Hermann-von-Helmholtz Platz 1<br />
76344 Eggenstein-Leopoldshafen<br />
Germany<br />
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Decommissioning and Waste Management<br />
Corrosion Processes of Alloyed Steels in Salt Solutions ı Bernhard Kienzler
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
Design and Development of a Radioeco<br />
logical Domestic User Friendly Code<br />
for Calculation of Radiation Doses and<br />
Concentration due to Airborn Radionuclides<br />
Release During the Accidental<br />
and Normal Operation in Nuclear<br />
Installations<br />
A. Haghighi Shad, D. Masti, M. Athari Allaf, K. Sepanloo, S.A.H. Feghhi and R. Khodadadi<br />
1.1 Introduction Though nuclear power is a good source of energy and is not generally a threat, a major reactor<br />
accident can lead to a catastrophe for people and the environment. The major health and environmental threat would<br />
be due to the escape of the fission products into the atmosphere. There have been instances of nuclear reactor accidents<br />
like the heavy water cooled and moderated reactor at Chalk River in Canada in 1952, the graphite moderated gas cooled<br />
reactor at Sellafield in Britain in 1957, the boiling water reactor at Idaho Falls in US in 1961, the pressurized water<br />
reactor on Three Mile Island in the US in 1979, the graphite moderated water cooled reactor at Chernobyl in Ukraine in<br />
1986, the sodium cooled fast breeder reactor at Monju in Japan in 1995 [Makhijani, 1996] and the boiling water reactor<br />
at Fukushima Daiichi NPP in Japan following an earthquake and tsunami in 2011. Among them, Chernobyl and<br />
Fukushima completely changed the human perception of radiation risk. On April 26, 1986, USSR suffered a major<br />
accident, which was followed by an extensive release to the atmosphere of large quantities of radioactive materials. An<br />
explosion and fire released huge quantities of radioactive particles into the atmosphere, which spread over much of the<br />
western USSR and Europe. The Chernobyl disaster was one of the two maximum classified event (level 7) on the<br />
International Nuclear Event Scale (the other being the Fukushima Daiichi nuclear disaster happened in 2011) and was<br />
the worst nuclear power plant accident in history in terms of cost and the resulting deaths. The battle to contain the<br />
contamination and avert a greater catastrophe ultimately involved over 500,000 workers and cost an estimated<br />
18 billion rubles. During the accident itself, 31 people died, and long-term effects such as cancers and deformities are<br />
still being accounted for. Unfortunately, the other severe accident happened on March 11, 2011; a powerful earthquake<br />
(magnitude 9.0) hit off the east coast of Japan. The tsunami triggered by the earthquake surged over the east coast of<br />
the Tohoku region, including Fukushima. The Fukushima Daiichi NPP’s cooling ability was lost and reactors were heavily<br />
damaged. Owing to controlled venting and an unexpected hydrogen explosion, a large amount of radioactive material<br />
was released into the environment. Consequently, many residents living around the NPP were exposed to radiation.<br />
In almost every respect, the consequences of the Chernobyl accident clearly exceeded those of the Fukushima accident.<br />
In both accidents, most of the radioactivity released was due to volatile radionuclides (noble gases, iodine, caesium, and<br />
tellurium) [G. Steinhauser, A. Brandl, T. E. Johnson, 2014].<br />
111<br />
RESEARCH AND INNOVATION<br />
1.2 The context<br />
The objective of the paper is to develop<br />
a domestic user friendly dynamic<br />
radio logical dose and model for accidental<br />
atmospheric release of radionuclides<br />
and normal operation from a<br />
nuclear facility, which has been coupled<br />
with a long-range atmospheric<br />
transport and Gaussian dispersion<br />
model. The research in this study is<br />
based on (i) atmospheric dispersion of<br />
radionuclides, (ii) dose and risk model<br />
development, (iii) validation of the<br />
model with FSAR of typically<br />
WWER-1000 Reactor. Models to<br />
represent the transport of radionuclides<br />
following atmospheric tests<br />
of nuclear weapons were developed<br />
during the 1950s and 1960s. Though<br />
radio nuclides have been released into<br />
the environment during routine operational<br />
conditions of nuclear facilities,<br />
accidents and nuclear weapons tests,<br />
the KIANA Advance Computational<br />
Computer Code model that was developed<br />
for this study was planned to<br />
predict all of radiation doses and risks<br />
in the case of a nuclear accident and<br />
normal operation in nuclear installations.<br />
The novelties in this research are<br />
to couple a KIANA Advance Computational<br />
Computer Code dynamic dose<br />
and risk model with a long-range<br />
atmospheric transport model to predict<br />
the radiological consequences due<br />
to accidental releases and normal<br />
operation in nuclear installations, and<br />
to perform the model simulation for<br />
NPP sites in IRAN territory and with<br />
another site specification data as far as<br />
it can be acquired. Most of the mechanisms<br />
and phenomena considered in<br />
each of the existing dose and risk<br />
calculation and environmental transfer<br />
models have been compiled in the<br />
newly developed single<br />
KIANA Advance Computational<br />
Computer Code to lead detailed modelling.<br />
An uncertainty and sensitivity<br />
analysis can also part of the study to<br />
determine the most influential parameters<br />
and their uncertainties on the<br />
results for users (if applicable). A huge<br />
amount of data, such as radioactivity<br />
concentration in food, pasture and<br />
doses, regarding the consequences<br />
of nuclear power plants’ accidents<br />
and normal conditions in literature<br />
was used for the development of<br />
Computer Code and its validation.<br />
Research and Innovation<br />
Design and Development of a Radio eco logical Domestic User Friendly Code for Calculation of Radiation Doses and Concentration due to Airborn Radio nuclides Release<br />
A. Haghighi Shad, D. Masti, M. Athari Allaf, K. Sepanloo, S.A.H. Feghhi and R. Khodadadi
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
RESEARCH AND INNOVATION 112<br />
1.3 The innovation<br />
The main features of this software and<br />
study can be summarized as follows:<br />
Exposure from all pathways is<br />
included- Ingestion pathways are<br />
modelled in such a detailed way<br />
that, translocation, -transfer between<br />
soil-plant, and feed-animal, food processing<br />
and storage, weathering, and<br />
dilution in the plant are all taken into<br />
account. Time dependency in radionuclide<br />
transfer in the environment<br />
considering food harvesting, sowing<br />
times, feeding regimes, and the<br />
growing up of a person are all taken<br />
into account. Individual doses for<br />
maximum and average individuals<br />
and for four age groups are calculated.<br />
Doses in the case of implementation<br />
of countermeasures are calculated.<br />
Collective doses for big cities can be<br />
calculated. Two different methods for<br />
stochastic risk modelling are applied.<br />
A probabilistic module has also<br />
been developed; namely, uncertainty<br />
analysis can be performed (if applicable).This<br />
study is regarded as unique<br />
since. The model algorithms, which<br />
the KIANA Advance Computational<br />
Computer Code developed for this<br />
study was based on IAEA safety report<br />
series [Müller, H. and Pröhl, G., 1993],<br />
has been modified; the KIANA<br />
Advance Computational Computer<br />
Code to be able to calculate inhalation<br />
doses from resuspension, individual<br />
doses in terms of both average and<br />
maximum habits, collective doses and<br />
late risks, and to utilize the recent<br />
knowledge in the dose and risk assessment<br />
area to the extent possible, such<br />
as dose conversion factors and risk<br />
coefficients etc.<br />
The long-range transport model,<br />
which the code/software developed<br />
for this study was coupled with,<br />
was also upgraded to increase the<br />
number of pollutants modelled to<br />
provide us easiness. Besides, extensive<br />
uncertainty and sensitivity analyses<br />
associated with 96 parameters have<br />
been performed for this study. The<br />
meteorological module in the existing<br />
environmental emergency response<br />
system is associated with 3-day-<br />
Domestic forecast meteorological<br />
data acquired through the State<br />
Meteorological Directorate. The dispersion<br />
model is the Developed AIREM<br />
and DOZAE M model that has the<br />
capability to predict trajectories,<br />
concentration, and deposition patterns<br />
in the case of nuclear accidents and<br />
normal operations. However, doses,<br />
risks, and activities in the food chain<br />
are not calculated with the existing<br />
system in IRAN. Since the newly<br />
developed KIANA Advance Computational<br />
Computer Code for this<br />
study is compatible with the existing<br />
system's dispersion code, it can easily<br />
be integrated into it.<br />
2.1 Atmospheric dispersion<br />
models<br />
Numerous radiation dose calculation<br />
tools have been developed over the<br />
years. They calculate trajectories,<br />
atmospheric transport and dispersion,<br />
age-dependent radiation doses, early<br />
and late health risks, monetary costs<br />
of the accidents, doses in the case<br />
of implementation of emergency<br />
actions, collective health risk, uncertainty<br />
analysis etc. Atmospheric<br />
dispersion methods in these tools<br />
can be based on simple Gaussian or<br />
numerical approaches. Short-range<br />
dispersion models usually use<br />
straight-line Gaussian plume model.<br />
These models are appropriate if the<br />
release is from a source that has<br />
dimensions, which are small compared<br />
to the distances at which concentrations<br />
are to be estimated. For<br />
example, for the distances out to<br />
5-10 km from the source point, if the<br />
terrain is relatively flat and has<br />
uniform surface conditions in all<br />
directions and if the atmospheric<br />
conditions at the time and location of<br />
the release completely control the<br />
transport and diffusion of material<br />
in the atmosphere short-range<br />
atmospheric dispersion models are<br />
preferred. Gaussian dispersion equations<br />
should be used to estimate concentrations<br />
up to the 80 km from the<br />
source under ideal conditions of flat<br />
terrain and no spatial variations of the<br />
wind field. Consequently, for a countrywide<br />
dispersion simulation, due to<br />
topo graphy and dispersion area, the<br />
straight-line Gaussian models can not<br />
be appropriate tools. Therefore, longrange<br />
atmospheric dispersion models<br />
are used in this paper. Dose assessment<br />
methodology in some aforementioned<br />
short range codes neglects<br />
ingestion pathway and calculation<br />
of doses in the late phase of the accident.<br />
These are coupled with simple<br />
radiation dose modelling algorithm,<br />
including only inhalation and external<br />
radiation pathways i.e. HotSpot,<br />
RASCAL and RTARC [Homann, S. G.,<br />
2010, Mcguire, S. A., Ramsdell, Jr., J. V.<br />
and Athey, G. F., 2007, Stubna M. and<br />
Kusovska Z. 1993] All radiation dose<br />
exposure pathways can be seen in<br />
Figure 1.<br />
Since short range codes generally<br />
calculate short-term doses incurred<br />
immediately after the accident and<br />
recommend emergency protective<br />
actions, such as intervention, sheltering<br />
and iodine pills, and long-term<br />
effects incurred from the ingestion<br />
pathway are not generally calculated<br />
with these types of codes. Some of<br />
the codes having a Gaussian plume<br />
methodology calculates ingestion<br />
doses, but not in a dynamic or<br />
| | Fig. 1.<br />
Radiation Dose Exposure Pathways in KIANA Advance Computational Computer Code.<br />
Research and Innovation<br />
Design and Development of a Radio eco logical Domestic User Friendly Code for Calculation of Radiation Doses and Concentration due to Airborn Radio nuclides Release<br />
A. Haghighi Shad, D. Masti, M. Athari Allaf, K. Sepanloo, S.A.H. Feghhi and R. Khodadadi
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
comprehensive way for real time<br />
releases i.e. GENII [Napier 20<strong>02</strong>].<br />
Long- range atmospheric transport<br />
models, on the other hand, generally<br />
focus on the calculation of the trajectories,<br />
atmospheric transport and<br />
dispersion, and are used for real time<br />
emergency preparedness purposes.<br />
These numerical models use multiple<br />
wind measurements in both the horizontal<br />
and vertical directions, and<br />
include terrain effects and vertical<br />
and horizontal wind shear. They also<br />
treat the parameter variables more<br />
realistically, such as surface roughness,<br />
deposition and variable atmospheric<br />
stability. Numerical modelling<br />
is widely used to study long-range<br />
airborne transport and deposition of<br />
radioactive matter after a hypothetical<br />
accident and normal operations.<br />
Ladas, Mesos, and Derma are those<br />
having long-range atmospheric<br />
transport and dispersion algorithm<br />
[ Draxler, R.R., and G.D. Hess, 1997,<br />
Suh et al., 2006, 2008, 2009, Apsimon,<br />
H.M.; Goddard, A.J.H.; Wrigley, J.,<br />
1985 and Sørensen, 1998; Sørensen et<br />
al., 2007]. Generally, these types of<br />
long-range dispersion codes are integrated<br />
with environmental transfer<br />
models to predict activity in the<br />
environment and the resulting doses.<br />
2.2 Radioecological models<br />
Two general classes of radioecological<br />
models have evolved; dynamic (transient)<br />
and equilibrium (steady state).<br />
Both describe the environment in<br />
terms of various „compartments” such<br />
as plant types, animal food products’<br />
types and soil layers. Some environmental<br />
media may be described in<br />
terms of more than one compartment,<br />
such as the roots, branches and trunk.<br />
When the equations are evaluated for<br />
sufficiently long times with unvarying<br />
values of the inputs and rate constants,<br />
the ratios of the concentrations<br />
of the radionuclides in the various<br />
compartments approach constant<br />
values. The system is then considered<br />
to be in equilibrium or in a steady<br />
state. These „quasi-equilibrium models”<br />
do not account for changes in<br />
plant biomass, livestock feeding<br />
regimes, or in growth and differential<br />
uptake of radioactive progeny during<br />
food chain transport. They are generally<br />
not appropriate for the assessment<br />
of critical short-term impacts<br />
from acute fallout events that may<br />
occur during the different times of the<br />
year and for applications related to<br />
the development of criteria for the<br />
implementation of actions. In the late<br />
1970’s the dynamic radioecological<br />
models started to emerge and led to a<br />
number of different such models.<br />
Since dynamic food chain transport<br />
models themselves are normally<br />
rather complex and require significant<br />
computing times most of the codes<br />
[e.g. Slaper et al., 1994, Hermann et<br />
al., 1984, Napier et al., 1988] neglect<br />
radiation exposure changes due to<br />
seasonal variations of radionuclides<br />
in the environment and human<br />
behaviour. For more realistic dose<br />
calculations, time dependency of<br />
the radionuclide transfer processes<br />
should be taken into account, leading<br />
to a dynamic modelling. Lots of radiological<br />
data are necessary for dynamic<br />
ingestion pathway modelling. After<br />
the significant parameters are determined<br />
with respect to their effects on<br />
the results by sensitivity analysis<br />
these data may be derived locally to<br />
lead to realistic modelling, PARATI,<br />
PATWHWAY, Ecosys-87, SPADE<br />
(quasi- equilibrium), COMIDA and<br />
DYNACON are some dynamic dose<br />
models for modelling environmental<br />
transfer of radionuclides in the food<br />
chain [Rochedo et.al. 1996, Whicker<br />
and Kirchner, 1987, Müller, H., Pröhl,<br />
G., 1993, Johnson and Mitchell, 1993;<br />
Mitchell, 1999, Abbott, M.L., Rood,<br />
A.S., 1993, Hwang, W.T., Lee, G.C. Suh,<br />
K.S. E.H. Kim].<br />
Since equilibrium in the model<br />
compartments (between vegetation,<br />
soil, and animal products) is not<br />
reached for a long time, it is essential<br />
to consider seasonality in the growing<br />
cycle of crops, feeding practices of<br />
domestic animals, and dietary habits.<br />
However, because of the temporal<br />
resolution demanded for the output, a<br />
great deal of information is required<br />
as input to this type of model, and<br />
extensive computer resources are<br />
required for the implementation.<br />
By using assumptions of quasiequilibrium<br />
(that is, relatively small<br />
changes from year to year in local<br />
conditions), the dynamic models may<br />
be simplified into equilibrium models.<br />
Knowledge of the contamination level<br />
of radionuclides in foodstuffs, including<br />
crops and animal products is<br />
essential information for deciding the<br />
implementation of protective actions.<br />
The degree of contamination can be<br />
evaluated through a model prediction<br />
from the amount of radionuclides<br />
deposited on the ground, as well as<br />
through direct measurements of<br />
radionuclides in foodstuffs. In developing<br />
systems for emergency preparedness<br />
as well as providing for<br />
rapid decision-making relating to<br />
foodstuffs, the characterization of<br />
action plans based on model predictions<br />
are likely to be appropriate. In<br />
the case of short-term deposition of<br />
radionuclides after a nuclear accident,<br />
the radionuclide concentration in<br />
foodstuffs is strongly dependent on<br />
the date (or season) when the deposition<br />
occurs, and on the time after the<br />
deposition due to factors such as<br />
crop growth and biokinetics of radionuclides<br />
ingested by the animals.<br />
Therefore, these dynamic environmental<br />
transfer models are generally<br />
implemented in a real time emergency<br />
or decision support systems, which<br />
are used before and during an ongoing<br />
emergency and provide sound<br />
basis countermeasures. In some radioecological<br />
models, such as COMIDA,<br />
CRLP and TERNIRBU [Brown, J. and<br />
Simmonds, J., R.,1995, KrcgewskiP.,<br />
1989, Kanyar, B., Fulop N., TERNIRBU,<br />
1996] soil compartment is modelled<br />
in such a way that it is divided into<br />
many layers: surface layer, root layer,<br />
and deep soil layer, etc.. The code<br />
developed for this study took AIREM,<br />
DOZAE M & S. R.S of IAEA models as<br />
reference. The data library for unlimited<br />
isotopes is available in the new<br />
software (sub routines). All natural<br />
phenomena important for the ingestion<br />
pathway modelling is taken into<br />
consideration in the new algorithm<br />
and model. Whereas, time dependent<br />
translocation, layered soil compartment,<br />
wet interception, and mushroom<br />
pathway are not available in the<br />
current model. Generally, the computer<br />
models developed for the prediction<br />
of routine releases from NPPs<br />
are based on the annual average concentrations<br />
of radionuclides in air<br />
and on the ground. However, for NPP<br />
routine atmospheric releases a<br />
dynamic model coupled with a longrange<br />
transport code was developed<br />
in another study [Kocar, C., 2003]. In<br />
the current study, to address the<br />
unique features of modelling operational<br />
radiological consequences of<br />
nuclear power plants, a few new<br />
algorithm based on the dynamic<br />
radioecological model had been<br />
considered. Different from the aforementioned<br />
dynamic model [Müller, H.<br />
and Pröhl, G., 1993], transfer mechanisms<br />
of C-14 and H-3 were coded and<br />
multi-location food supply and interregional<br />
moves of people in the computational<br />
domain were permitted.<br />
In this study, inhalation doses from<br />
both passages of the cloud and resuspension<br />
of deposited activity are<br />
calculated and accidental releases are<br />
simulated, but the previous one is for<br />
operational releases are modelled and<br />
RESEARCH AND INNOVATION 113<br />
Research and Innovation<br />
Design and Development of a Radio eco logical Domestic User Friendly Code for Calculation of Radiation Doses and Concentration due to Airborn Radio nuclides Release<br />
A. Haghighi Shad, D. Masti, M. Athari Allaf, K. Sepanloo, S.A.H. Feghhi and R. Khodadadi
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
RESEARCH AND INNOVATION 114<br />
| | Fig. 2.<br />
Summary of Code Algorithms.<br />
H-3 and C-14 releases which are of<br />
great significance for operational<br />
releases are modelled. In this study,<br />
individual doses are calculated for<br />
two different habits of the people in<br />
term of food consumption and gamma<br />
reduction.<br />
3.1 KIANA advance<br />
computational computer<br />
code structure<br />
A deterministic dose calculation<br />
model called KIANA Advance Computational<br />
Computer Code has been<br />
developed for this study. For the dose<br />
assessment, all exposure pathways<br />
have been implemented as follows:<br />
Transfer of radionuclides through<br />
food chains and the subsequent<br />
internal exposures of humans due to<br />
ingestion of contaminated foodstuffs-<br />
Internal exposure due to inhalation of<br />
radionuclides during passage of cloud<br />
and from resuspension of deposited<br />
radionuclides- External exposure<br />
from radionuclides in the passing<br />
cloud- External exposure from radionuclides<br />
deposited on the ground. The<br />
design of the KIANA Code is flexible<br />
such that it can be adopted anywhere<br />
for any nuclear power plant/nuclear<br />
installation site with suitable modifications<br />
to the database.<br />
3.2 Ingestion pathway<br />
Ingestion pathway calculations in<br />
KIANA Advance Computational<br />
Computer Code take into account<br />
the following process and data:<br />
Yield of grass and agricultural food<br />
products. Harvesting and sowing time<br />
of grass and agricultural products.<br />
Translocation within plants. Interception.<br />
Weathering from plant surfaces.<br />
Dilution of radionuclide concentrations<br />
due to plant growth. Uptake<br />
by plant roots. Migration within the<br />
soil and Plant contamination due to<br />
resuspended soil. Different livestock<br />
feeding regimes. Storage times for<br />
fodder and human food products.<br />
Changes in radionuclide concentrations<br />
due to food processing. Age<br />
dependent ingestion dose coefficients<br />
for the public are taken from ICRP 72<br />
[1996]. Dose coefficients for 3 months<br />
infant, 5 year old children, 15 years<br />
old teen and adult are used. ICRP<br />
ingestion dose conversion factors take<br />
into account integration period of<br />
50 years for adults and 70 year for<br />
children. Input data to the ingestion<br />
modelling is the time integrated<br />
air concentrations, and deposited<br />
activity from any dispersion model or<br />
measured data. Ingestion of tap water<br />
and aquatic food products are not<br />
considered in KIANA Advance Computational<br />
Computer Code.<br />
3.3 Activity concentration<br />
of plant products<br />
The contamination of plant products<br />
as a function of time results from the<br />
direct contamination of the leaves and<br />
the activity transfer from the soil by<br />
root uptake and resuspension:<br />
C i (t) = C i,f (t) + C i,r (t)<br />
C i (t); total contamination<br />
of plant type i,<br />
C i,f (t); contamination of plant type i<br />
due to foliar uptake,<br />
Ci,r(t); contamination of plant type i<br />
due to root uptake<br />
Pasture and 13 different plant products,<br />
i.e. corn cobs, spring and winter<br />
wheat, spring and winter barley, rye,<br />
fruits, berries, and root, fruit and leafy<br />
vegetables, potatoes and beet can be<br />
modelled by KIANA Advance Computational<br />
Computer Code.<br />
3.4 Foliar uptake<br />
of radionuclides:<br />
Calculation of the contamination of<br />
plants must distinguish between<br />
plants that are used totally (leafy vegetables<br />
and grass) and plants of which<br />
only a special part is used. The activity<br />
concentration at time after the deposition<br />
is determined by the initial contamination<br />
of the plant and activity<br />
loss due to weathering effects (rain,<br />
wind) and radioactive decay and<br />
growth dilution. For plants that are<br />
totally consumed growth, excluding<br />
pasture grass, growth is implicitly<br />
considered because the activity deposited<br />
onto leaves is related to the<br />
yield at harvest. Interception factor is<br />
defined as the ratio of the activity initially<br />
retained by the standing vegetation<br />
immediately subsequent to the<br />
deposition event to the total activity<br />
deposited. Radionuclides to agricultural<br />
plants may be intercepted by dry<br />
process, wet process, or a combination<br />
of both. The interception fraction is<br />
dependent on the plant intensity in<br />
the area, stage of development of the<br />
plant, and generally leaf area of the<br />
crops. In the present model, a single<br />
coefficient was used and interception<br />
factors for grass and other plants were<br />
taken from DoseCAL code; the interception<br />
factor for grass and, fruits and<br />
vegetables is assumed to be 0.3 and<br />
for the grain and cereals it is 0.005.<br />
The activity concentration at the time<br />
of harvest is given<br />
(3.8)<br />
C i,f (t); concentration of activity in<br />
plant type i at time of harvest,<br />
f i ; interception factor<br />
for plant type i,<br />
A i ; total deposition (Bq.m –2 ) of<br />
plant type i at time of harvest,<br />
λ w ; loss rate (d –1 )<br />
due to weathering,<br />
λ r ; decay rate (d –1 ),<br />
Δt; time span between deposition<br />
and harvest (d)<br />
The approach for pasture grass is<br />
different because of its continuous<br />
harvest. Here, the decrease in activity<br />
due to growth dilution is explicitly<br />
considered.<br />
C g,f (t); activity concentration<br />
(Bq.kg –1 ) in grass at time t<br />
after deposition,<br />
f g ; interception factor for grass,<br />
A g ; total activity deposited onto<br />
grass (Bq.m –2 )<br />
Y g ; yield of grass at time of<br />
deposition (kg.m –2 )<br />
a; fraction of activity translocated<br />
tot the root zone,<br />
λ b ; dilution rate by increase<br />
of biomass (d –1 ),<br />
λ t ; rate of activity decrease (d –1 )<br />
due to translocation to the<br />
root zone<br />
For the weathering rate constant λw; a<br />
value equivalent to a half-life 14 d is<br />
taken from Farmland code (NRPB,<br />
1995) and for rate of activity decrease<br />
due to translocation to the root zone<br />
λt; 1.16x10-2 d-1 with a contribution<br />
fraction a= 0.05 using different measurement<br />
of grass contamination after<br />
the Chernobyl accident are assumed<br />
[Pröhl, 1990]. For plants that are only<br />
partly used for animal feeding or<br />
human consumption the translocation<br />
Research and Innovation<br />
Design and Development of a Radio eco logical Domestic User Friendly Code for Calculation of Radiation Doses and Concentration due to Airborn Radio nuclides Release<br />
A. Haghighi Shad, D. Masti, M. Athari Allaf, K. Sepanloo, S.A.H. Feghhi and R. Khodadadi
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
from leaves to the edible part of the<br />
plant has to be considered. This process<br />
strongly depends on the physiological<br />
behaviour of the element<br />
considered. It is important for mobile<br />
elements such as caesium, iodine,<br />
tellurium whereas for immobile<br />
elements including strontium, barium,<br />
zirconium, niobium, ruthenium,<br />
cerium, plutonium only direct deposition<br />
onto edible parts of the plants<br />
play role. Translocation process is<br />
quantified by translocation factor Ti,<br />
which is defined as the fraction of the<br />
activity deposited on the foliage being<br />
transferred to the edible parts of the<br />
plant until<br />
harvest. It is dependent on the<br />
element, plant type and time between<br />
deposition and harvest. Translocation<br />
factors for agricultural food products<br />
for caesium, strontium and other<br />
elements were taken from IAEA<br />
TRS-472 (2010). Translocation factors<br />
for only the ripening stage is applied<br />
in KIANA Advance Computational<br />
Computer Code.<br />
3.5 Root uptake<br />
of radionuclides<br />
The estimation of the root uptake of<br />
radionuclides assumes that the radionuclides<br />
are well mixed within the entire<br />
rooting zone. The concentration<br />
of activity due to root uptake is calculated<br />
from the concentration of activity<br />
in the soil using transfer factor TFi<br />
that gives the ratio of concentration of<br />
activity in plants (fresh weight) and<br />
soil (dry weight)<br />
C i,r (t) = TF i C s (t)<br />
C i, r (t); concentration of activity<br />
(Bq/kg) in plant type i due to<br />
root uptake at time t after the<br />
deposition,<br />
TF i ; soil-plant transfer factor for<br />
plant type i,<br />
Cs(t); concentration of activity<br />
(Bq/kg) in the root zone of<br />
soil at time t<br />
The soil conditions which soil-plant<br />
transfer factors are based are often<br />
characterised by a low pH value together<br />
with a high organic content,<br />
and low contents of clay, potassium<br />
and calcium. Such soils are frequently<br />
found in upland areas, Scandinavia,<br />
and parts of Eastern Europe. (Pröhl,<br />
G., and Müller, H., 1993) The concentration<br />
of activity in the root zone of<br />
soil is given by;<br />
A s ; total deposition to soil<br />
(Bq.m –2 )<br />
L; depth of root zone (m)<br />
ρ; density of soil (kg.m –3 )<br />
λ s ; rate of activity decrease due<br />
to migration out of the root<br />
zone<br />
λ r ; rate of fixation (d –1 )<br />
The migration rate λ s is estimated<br />
according to;<br />
v a ; velocity of percolation water<br />
in soil (m.a –1 )<br />
K d ; distribution coefficient<br />
(cm 3 .g –1 )<br />
θ; water content of soil (g.g –1 )<br />
3.6 Contamination<br />
of animal products<br />
The contamination of animal products<br />
results from the activity intake of<br />
the animals and the kinetics of the<br />
radionuclides within the animals.<br />
Inhalation of radionuclides by the<br />
animals is not considered; this pathway<br />
may be relevant for milk contamination<br />
in certain cases, but it is<br />
unimportant for resulting doses. The<br />
amount of activity ingested by the<br />
animals is calculated from the concentration<br />
of activity in the different<br />
foodstuffs and the feeding rates;<br />
A a,m (t); activity intake rate of the<br />
animal m (Bq.d –1 ),<br />
K m ; number of different feedstuffs<br />
fed to the animal m,<br />
C k (t); activity concentration<br />
(Bq.kg –1 ) in feedstuffs k,<br />
I k,m (t); feeding rate (kg.d –1 ) for<br />
feedstuffs k and animal m<br />
Soil ingestion is also considered in<br />
KIANA Advance Computational Computer<br />
Code. Soil intake of animals<br />
varies widely depending on the<br />
grazing management and the condition<br />
of the pasture. If the feeding of<br />
mechanically prepared hay and silage<br />
during winter and an intensive<br />
grazing regime on well fertilized<br />
pasture are assumed a mean annual<br />
intake of 2.5% of the grass dry matter<br />
intake seems to be appropriate. This<br />
nuclide independent value is equivalent<br />
to soil-plant transfer factor of<br />
5x10-3 and it is added to the transfer<br />
and resuspension factor in KIANA<br />
Advance Computational Computer<br />
Code. This means that for all elements<br />
with a transfer factor lower than this<br />
value, soil eating is the dominating<br />
long term pathway for the contamination<br />
for milk and meat from grazing<br />
cattle, presuming that resorption in<br />
the gut is the same for soil-bound and<br />
plant incorporated radionuclides.<br />
Seven different animal products,<br />
namely cow, sheep and goat milk, and<br />
lamb, beef cattle, egg and chicken,<br />
can be modelled by KIANA Advance<br />
Computational Computer Code.<br />
Transfer of radionuclides from fodder<br />
into animal products is calculated as<br />
follows:<br />
C m (t); activity concentration<br />
in animal product m at time t,<br />
TF m ; transfer factor (d.kg –1 )<br />
for animal product m,<br />
j; number of biological transfer<br />
rates,<br />
a mj ; fraction of biological transfer<br />
rates,<br />
λ b,mj ; biological transfer rate j (d –1 )<br />
for animal product m<br />
For sheep and goat milk transfer<br />
factors 10 times higher than for cow<br />
milk are assumed. For lamb, goat’s<br />
meat, and chicken, the transfer was<br />
estimated from the feed-beef transfer<br />
factor by applying correction factors<br />
for the lower body mass. Correction<br />
factors are 3 for lamb, and goat’s meat<br />
and 100 for chicken. [Müller, H. and<br />
Pröhl, G., 1993] Biological turnover<br />
rates of animal products were taken<br />
from DOZAE M, AIREM and DoseCAL.<br />
3.7 The processing and<br />
storage of foodstuffs<br />
The processing and storage of foodstuffs<br />
in order to take advantage of the<br />
radioactive decay and dilution during<br />
these processes are taken into account<br />
in the model. The enrichment of minerals<br />
in the outer layers of grains and<br />
the fractionation in the milling products<br />
is considered. Besides, the radioactive<br />
decay during processing and<br />
storage is taken into account. The storage<br />
presumes the stability of the foodstuffs<br />
or the possibility to convert the<br />
foodstuffs into stable products. Storage<br />
times are considered to be mean<br />
time between the harvest and beginning<br />
of product consumption. Concentration<br />
of activity in products is<br />
calculated from the raw product by<br />
the following relation:<br />
C k (t) = C ko (t–t pk )P k exp(–λ t pk )<br />
RESEARCH AND INNOVATION 115<br />
Research and Innovation<br />
Design and Development of a Radio eco logical Domestic User Friendly Code for Calculation of Radiation Doses and Concentration due to Airborn Radio nuclides Release<br />
A. Haghighi Shad, D. Masti, M. Athari Allaf, K. Sepanloo, S.A.H. Feghhi and R. Khodadadi
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
RESEARCH AND INNOVATION 116<br />
| | Fig. 3.<br />
Code Algorithms of contamination of plant products as a function of time results from the direct contamination of the leaves and the activity transfer from the soil<br />
by root uptake and re-suspension that used in construction of KIANA Advance Computational Computer Code.<br />
| | Fig. 4.<br />
Code Algorithms calculation of Inhalation doses for each incremental time<br />
step (in days) that used in construction of KIANA Advance Computational<br />
Computer Code.<br />
C k (t); activity concentration<br />
(Bq/kg) in product k ready<br />
for consumption at time t,<br />
C ko ; activity concentration<br />
(Bq/kg) in raw product<br />
at time t,<br />
P k ; processing factor<br />
for product k,<br />
λ r ; radioactive decay constant<br />
(d –1 ),<br />
t pk ; storage and processing<br />
time (d) for product k<br />
3.8 Activity intake and<br />
exposure<br />
The intake of activity by humans is<br />
calculated from the time-dependent<br />
concentrations of activity in foodstuffs<br />
and the human consumption rate:<br />
A h (t); human intake rate (Bq.d –1 )<br />
of activity,<br />
C k (t); concentration of activity<br />
(Bq.kg –1 ) of foodstuff k,<br />
V k (t); consumption rate (kg.d –1 )<br />
of foodstuff k<br />
The foodstuffs are assumed to be<br />
locally produced. Food consumption<br />
data that is very important for<br />
calculating dose exposure by ingestion<br />
pathway is different depending<br />
on where people live. Country specific<br />
data on consumption of food products<br />
have been used to lead to realistic<br />
modelling. The dose Ding(t) due to<br />
ingestion of contaminated foodstuffs<br />
within time t after the deposition, is<br />
given by the following;<br />
D ing (t); ingestion dose (Sv)<br />
DF; age dependent dose factor<br />
for ingestion (Sv.Bq –1 )<br />
4 Total dose calculation<br />
KIANA Advance Computational Computer<br />
Code calculates yearly doses for<br />
each age group and for each sector –<br />
segment after the accident. Agricultural<br />
food products' activities are<br />
calculated at each year's harvest,<br />
grass and animal products' activities<br />
are calculated on a monthly basis.<br />
All aforementioned pathways are<br />
included in dose calculations as shown<br />
below:<br />
Dose total = Dose inhalation + Dose ingestion +<br />
Dose cloudshine + Dose groundshine<br />
Research and Innovation<br />
Design and Development of a Radio eco logical Domestic User Friendly Code for Calculation of Radiation Doses and Concentration due to Airborn Radio nuclides Release<br />
A. Haghighi Shad, D. Masti, M. Athari Allaf, K. Sepanloo, S.A.H. Feghhi and R. Khodadadi
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
RESEARCH AND INNOVATION 117<br />
| | Fig. 5.<br />
Code Algorithms calculation of Activity concentration of plant products Root uptake of radionuclides that used in construction of KIANA Advance Computational<br />
Computer Code.<br />
| | Fig. 6.<br />
Code Algorithms concentration, activity intake rate of the animal m (Bq. d -1 ), that used in construction of KIANA Advance Computational Computer Code.<br />
Dose total ; total dose (Sv)<br />
Dose inhalation ; inhalation dose (Sv)<br />
Dose ingestion ; ingestion dose (Sv)<br />
Dose cloudshine ; cloudshine dose (Sv)<br />
A person is assumed to be as an infant<br />
up to 1 year, as a child up to 9 years, as<br />
teen up to 16 years and as an adult up<br />
to 70 years; namely when calculating<br />
long term doses after the accident<br />
growing up of a person is taken into<br />
account in terms of his/her food<br />
consumption habits, sensitivity to<br />
doses and occupancy factors.<br />
4.1 Calculation of collective<br />
doses<br />
The impact of an accident on the<br />
population as a whole depends not<br />
only on the deposition, atmospheric<br />
activity levels and dose obtained,<br />
but also on the population living in<br />
Research and Innovation<br />
Design and Development of a Radio eco logical Domestic User Friendly Code for Calculation of Radiation Doses and Concentration due to Airborn Radio nuclides Release<br />
A. Haghighi Shad, D. Masti, M. Athari Allaf, K. Sepanloo, S.A.H. Feghhi and R. Khodadadi
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
RESEARCH AND INNOVATION 118<br />
| | Fig. 7.<br />
Code Algorithms of Concentration of activity in products is calculated from<br />
the raw product that used in construction of KIANA Advance Computational<br />
Computer Code.<br />
| | Fig. 8.<br />
Code Algorithms intake of activity by humans is calculated from the<br />
time-dependant concentrations of activity in foodstuffs and the human<br />
consumption rate that used in construction of KIANA Advance<br />
Computational Computer Code (upper part of the diagram).<br />
Code Algorithms for dose Ding(t) due to ingestion of contaminated<br />
foodstuffs within time t after the deposition, is given by the following<br />
that used in construction of KIANA Advance Computational Computer<br />
Code (lower part of the diagram).<br />
that particular area. For example<br />
the deposition, atmospheric activity<br />
levels, dose obtained and individual<br />
health risk, due to any NPP accident,<br />
may be very high, but these high<br />
values may not mean anything if there<br />
is no one living there. Consequently,<br />
better representation of the collective<br />
doses or risk of an accident, nuclear<br />
and nonnuclear, can be obtained by<br />
multiplying the individual dose or<br />
health risk by the number of people<br />
living in the receptor. For this study,<br />
average values all over the geographical<br />
regions were taken into<br />
account, since data does not vary<br />
considerably over the regions. On<br />
the other hand. Transfer factors for<br />
animal- feeds and soil-plants, and fixation<br />
rates, distribution coefficients,<br />
translocation factors, dose conversion<br />
factors and metabolic turnover rates<br />
in animals for all related isotopes, and<br />
processing factors and storage days<br />
for food products, weathering rates,<br />
interception factors and soil density,<br />
water content of soil, percolation<br />
water velocity, dilution factor of<br />
the grass, depth of root zone, the<br />
references in which Cs-137 default<br />
values were taken for validation study,<br />
were used in KIANA Advance Computational<br />
Computer Code during<br />
simulation of the case studies. Since<br />
most of these data are not dependent<br />
on location.<br />
5 Result and discussions<br />
Dispersion of radionuclides is also an<br />
application area of KIANA Advance<br />
Computational Computer Code. User<br />
supplied inputs for KIANA Advance<br />
Computational Computer Code calculations<br />
are pollutant species<br />
characteristics, emission parameters,<br />
gridded meteorological fields and<br />
output deposition grid definitions.<br />
The horizontal deformation of the<br />
wind field, the wind shear, and the<br />
vertical diffusivity profile are used to<br />
compute the dispersion rate. Gridded<br />
meteorological data are required for<br />
regular time intervals. The meteorological<br />
data fields may be provided on<br />
one of the different vertical coordinate<br />
system: Pressure-sigma, pressure<br />
absolute, terrain-sigma or a hybrid<br />
absolute-pressure-sigma The doses<br />
and time dependant radioactivity concentration<br />
values in the food products<br />
and pasture grass predicted by KIANA<br />
Advance Computational Computer<br />
Code have been compared with those<br />
of different codes (AIREM,DOZA)<br />
which participated in assessment task,<br />
and data measured in Boshehr, and<br />
Finland after Chernobyl accident.<br />
Radionuclide<br />
Activity (Bq)<br />
Sr-89<br />
8.5E+09<br />
Kr-90<br />
6.7E+13<br />
Rb-90<br />
6.4E+13<br />
Sr-90<br />
2.2E+07<br />
Sr-91<br />
2.6E+11<br />
Sr-92<br />
2.1E+11<br />
Mo-99<br />
1.1E+09<br />
Ru-103<br />
9.3E+08<br />
Ru-106<br />
1.3E+07<br />
Ru-106<br />
1.3E+07<br />
Ru-106<br />
1.3E+07<br />
Te-131<br />
9.3E+10<br />
I-131 3.1E+13<br />
Te-132<br />
1.2E+10<br />
I-132 8.3E+13<br />
Te-133<br />
1.6E+11<br />
I-133 6.8E+13<br />
Xe-133<br />
1.7E+13<br />
I-134 6.3E13<br />
Cs-134<br />
1.8E+12<br />
I-135 5.1E+13<br />
Xe-135<br />
1.1E+13<br />
Cs-137<br />
2.8E+12<br />
Xe-138<br />
4.6E+13<br />
C-138 4.9E+13<br />
Ba-139<br />
9.9E+11<br />
Ba-140<br />
1.1E+10<br />
La-140<br />
1.4E+09<br />
141-Ce<br />
1.8E+09<br />
Ce-144<br />
2.0E+08<br />
Br-84<br />
1.5E+13<br />
Kr-85m<br />
1.2E+13<br />
Kr-85<br />
3.3E+09<br />
Br-87<br />
3.7E+13<br />
Kr-87<br />
3.9E+13<br />
Kr-88<br />
4.9E+13<br />
Rb-88<br />
4.9E+13<br />
Kr-89<br />
6.7E+13<br />
Rb-89<br />
7.1E+13<br />
Pr-144<br />
1.8E+08<br />
Zr-95<br />
1.2E+09<br />
Nb-95<br />
1.2E+07<br />
Zr-97<br />
7.4E+10<br />
Nb-97<br />
6.7E+10<br />
Na-24<br />
2.7E+11<br />
K-42 1.2E+12<br />
Fe-59<br />
1.9E+07<br />
Co-58<br />
7.4E+07<br />
Cr-51<br />
1.4E+08<br />
Mn-54<br />
1.9E+07<br />
Co-60<br />
2.0E+08<br />
Activities (Bq)<br />
I-131 3.1E+11<br />
I-132 8.4E+11<br />
I-133 6.9E+11<br />
I-134 6.3E+11<br />
I-135 5.1E+11<br />
| | Tab. 1.<br />
Radionuclide release to environment after<br />
severe accident at typically WWER-1000 NPP<br />
such as Boushehr.<br />
Those codes are dynamic (timedependent),<br />
and only one of them; i.e.<br />
DoseCAL, is quasi-equilibrium. Since<br />
KIANA Advance Computational Computer<br />
Code is developed as dynamic<br />
software (such as DoseCAL), only<br />
dynamic codes' results are presented<br />
for comparison. KIANA Advance<br />
Computational Computer Code has a<br />
Research and Innovation<br />
Design and Development of a Radio eco logical Domestic User Friendly Code for Calculation of Radiation Doses and Concentration due to Airborn Radio nuclides Release<br />
A. Haghighi Shad, D. Masti, M. Athari Allaf, K. Sepanloo, S.A.H. Feghhi and R. Khodadadi
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
RESEARCH AND INNOVATION 119<br />
| | Fig. 9.<br />
Code Algorithms for calculation of ground level air concentration at downwind distance x in the sector) p (Bq/m3), when the source and receptor on the same<br />
building surface that used in construction of KIANA Advance Computational Computer Code.<br />
capability to make simulation with<br />
seven pollutants at a time at most.<br />
Since some more radionuclides<br />
considered being most important in<br />
terms of their effects in the environment<br />
are used to represent accidental<br />
release of radionuclides in the literature,<br />
HYSPLIT model's source code<br />
has been modified to simulate more<br />
pollutants to provide us easiness for<br />
this study.<br />
In this study, dry deposition velocity<br />
is assumed to be a constant for<br />
each radionuclide and surface type.<br />
the dry deposition velocity values for<br />
agricultural surface type were used in<br />
our simulations. To strengthen our<br />
assumption, size of the particles<br />
released into environment in the case<br />
of a nuclear accident was also investigated.<br />
Release height is another<br />
important parameter for subsequent<br />
dispersion modelling in KIANA<br />
Advance Computational Computer<br />
Code. Literature studies show that<br />
variations of the initial plume rise<br />
below the mixing height only slightly<br />
affect the results outside the local<br />
scale, whereas plume rise above that<br />
level led to significantly changed patterns<br />
with relatively little depositions<br />
on the local and meso-scales. Thus,<br />
a release into the atmospheric<br />
boundary level compared with a<br />
release to the free troposphere leads<br />
to large differences in the deposition<br />
patterns and lifetimes (a week or<br />
more) of radionuclides within the<br />
atmosphere. Release height was<br />
assumed as a line source between<br />
50-100 meter considering all the accident<br />
type, release points in the reactor<br />
and plume rise. In 1986, there was a<br />
recommendation to postpone the<br />
open field sowing of lettuce, spinach<br />
and other fast growing vegetables.<br />
Although it is not clear to what extent<br />
this recommendation was implemented<br />
across all regions, the fact<br />
that KIANA Advance Computational<br />
Computer Code did not account for<br />
any delay in sowing. However, only<br />
root uptake for leafy vegetables was<br />
taken into account in DoseCAL. Leafy<br />
vegetables activities predicted by<br />
KIANA Advance Computational Computer<br />
Code are within the uncertainty<br />
band of the measured values and the<br />
best of all other code results. The<br />
probability for T-test for is 0.834,<br />
which is close to one. The differences<br />
between the predictions of the codes<br />
which participated in VAMP exercise,<br />
may be raised from misinterpretation<br />
of site-specific information; namely<br />
taking into account different assumptions,<br />
or using different soil-plant and<br />
feed-animal transfer factors as stated<br />
in IAEA TECDOC-904 (1996). Inhalation<br />
and external doses predicted<br />
by KIANA Advance Computational<br />
Computer Code as the as the DoseCAL<br />
calculations are rather consistent<br />
compared to other codes' predictions.<br />
Ingestion doses predicted by KIANA<br />
Advance Computational Computer<br />
Code, on the other hand, is lower<br />
compared to the other codes. Since in<br />
ingestion module of KIANA Advance<br />
computational Computer Code, mushroom,<br />
fish, game animals are not taken<br />
into account, whereas other food<br />
products, i.e. fruits, root and fruit vegetables,<br />
eggs have been considered as<br />
default. it is almost equal to beef consumption,<br />
and most of the ingestion<br />
doses calculated by most of the models<br />
participated in validation exercise<br />
were incurred from fish consumption.<br />
Hence, the difference in ingestion<br />
dose prediction in KIANA Advance<br />
Computational Computer Code can be<br />
attributed to fish pathway. Ingestion<br />
doses are highly dependent on consumption<br />
rates as seen from the differences<br />
between the doses for average<br />
and maximum individuals. Inhalation<br />
doses are the highest for the children,<br />
though the highest inhalation DCFs<br />
are of infants, breathing rates for<br />
the children are higher than for the<br />
infants. Inhalation dose for teens and<br />
Research and Innovation<br />
Design and Development of a Radio eco logical Domestic User Friendly Code for Calculation of Radiation Doses and Concentration due to Airborn Radio nuclides Release<br />
A. Haghighi Shad, D. Masti, M. Athari Allaf, K. Sepanloo, S.A.H. Feghhi and R. Khodadadi
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
RESEARCH AND INNOVATION 120<br />
adults are lower than children, since<br />
DCF’s for radioisotopes considered in<br />
case study for children are higher than<br />
those for adults except caesium isotopes.<br />
External doses are calculated<br />
for infants and others (child, teen and<br />
adult). Although DCF’s for infants are<br />
1.5 times higher than the others, the<br />
correction factor for shielding is lower<br />
for infants than others, hence external<br />
doses are lower for infants. External<br />
ground doses are lower for infants<br />
too, as far as the years passed after the<br />
accident is concerned. In the case of<br />
implementation of countermeasures<br />
on food consumption restrictions in<br />
the first year after the accident, the<br />
ingestion and total doses for average<br />
individuals for all age groups can be<br />
predicted by KIANA Advance computational<br />
Computer Code. . the most<br />
dose contributing isotopes are Cs-134,<br />
Cs-137 and I-131 in the first year after<br />
the accident. In the long term, Cs-134<br />
and Cs-137 (Table 1) remain in the<br />
environment due to their long radioactive<br />
half-lives. The dose consequence<br />
of Xe-133 is the least amongst<br />
others due to its very short half-life,<br />
i.e. 5.25 days and its inertness. Lifetime<br />
doses incurred from Cs-137,<br />
Cs-134 and I-131 are more than 95%<br />
of total doses. Ingestion doses are the<br />
highest for the infant, child, adult and<br />
teen; respectively in the first year after<br />
the accident since the ingestion DCF<br />
for I-131 for the infants is the highest.<br />
Infant ingestion doses remain the<br />
highest as years pass after the accident,<br />
since infant's growing up is<br />
taken into account and their food<br />
consumption increases when they are<br />
growing.<br />
References<br />
| | Abbott, M.L., Rood, A.S., COMIDA,<br />
A Radionuclide Food Chain Model for<br />
Acute Fallout Deposition, 1993.<br />
| | Abbott, M.L., Rood A.S., Comida: A<br />
radionuclide food chain model for acute<br />
fallout 6825 PNNL-14321 deposition,<br />
Health Phys 66: 17–29, 1994.<br />
| | Absalom JP, Young SD, Crout NMJ,<br />
Radiocaesium fixation dynamics:<br />
Measurement in six Cumbrian soils.<br />
European Journal of Soil Science<br />
46:461-469,1995.<br />
| | INTERNATIONAL ATOMIC ENERGY<br />
AGENCY. Generic Models for Use in<br />
Assessing the Impact of Discharges of<br />
Radioactive Substances to the<br />
Environment. Safety Report Series<br />
No 19, Vienna (2001).<br />
| | ANL/EAD-4, User’s Manual for RESRAD<br />
Version 6, 2001.Anspaugh, L.R., Shinn,<br />
J.H., Phelps, P.L., Kennedy, N.C., Resuspension<br />
and redistribution of plutonium<br />
in soils, Health Phys. 29 (1975) 571–582.<br />
| | Apsimon, H.M.; Goddard, A.J.H.;<br />
Wrigley, J., Long-range atmospheric<br />
dispersion of radioisotopes. The MESOS<br />
model. Atmospheric Environment<br />
(1967) vol. 19 issue 1 1985. p. 99-111.<br />
| | ARGOS home page,<br />
http://www.pdc-argos.com/<br />
[last accessed on 1 st of August, 2014]<br />
| | Baklanov A., Sorensen J.H.,<br />
Parameterization of Radionuclide<br />
Deposition in Atmospheric Long Range<br />
Transport Modeling, 2000.<br />
| | Bauer, L.R., and Hamby, D.M.: 1991,<br />
Relative Sensitivities of Existing and<br />
Novel Model Parameters in<br />
Atmospheric Tritium Dose Estimates,<br />
Rad. Prot. Dosimetry. 37, 253-260.<br />
| | Bellman, R., and Astrom, K.J.: 1970,<br />
On Structural Identifiability, Math.<br />
Biosci. 7, 329-339.<br />
| | Bergstroem, U., Nordlinder, S., Studsvik<br />
Eco and Safety AB, Nykoeping, Sweden,<br />
1981.<br />
| | Box, G.E.P., Hunter, W.G., and Hunter,<br />
J.S.: 1978, Statistics for Experimenters:<br />
an Introduction to Design, Data<br />
Analysis, and Model Building. John<br />
Wiley & Sons. New York.<br />
| | Breshears, D.D.: 1987, Uncertainty and<br />
sensitivity analyses of simulated<br />
concentrations of radionuclides in milk.<br />
Fort Collins, CO: Colorado State<br />
University, MS Thesis, pp. 1-69.149<br />
| | Brown, J. and Simmonds, J., R.,<br />
FARMLAND: A Dynamic Model for the<br />
Transfer of Radionuclides through<br />
Terrestrial Foodchains, 1995.<br />
| | Ciffroy, P., Siclet, F., Damois, C., Luck, M.,<br />
Duboudin, C., A dynamic model for<br />
assessing radiological consequences of<br />
routine releases in the Loire river:<br />
Parameterisation and uncertainty/<br />
sensitivity analysis, Journal of Environmental<br />
Radioactivity 83 (2005) 9-48.<br />
| | Christoudias, T. and Lelieveld, J.,<br />
Modelling the global atmospheric<br />
transport and deposition of radionuclides<br />
from the Fukushima Daiichi<br />
nuclear accident, Atmos. Chem. Phys.,<br />
13, 1425–1438, 2013.<br />
| | Conover, W.J.: 1980, Practical Nonparametric<br />
Statistics. 2 nd edn. John<br />
Wiley & Sons, New York.<br />
| | Cox, N.D.: 1977, Comparison of Two<br />
Uncertainty Analysis Methods, Nuc. Sci.<br />
and Eng. 64, 258-265.<br />
| | Crick, M.J., Hill, M.D. and Charles, D.:<br />
1987, The Role of Sensitivity Analysis in<br />
Assessing Uncertainty. In: Proceedings<br />
of an NEA Workshop on Uncertainty<br />
Analysis for Performance Assessments<br />
of Radioactive Waste Disposal Systems,<br />
Paris, OECD, pp. 1-258.<br />
| | Cunningham, M.E., Hann, C.R., and<br />
Olsen, A.R.: 1980, Uncertainty Analysis<br />
and Thermal Stored Energy Calculations<br />
in Nuclear Fuel Rods, Nuc. Technol. 47,<br />
457-467.<br />
| | Cukier, R.I., Fortuin, C.M., Shuler, K.E.,<br />
Petschek, A.G. and Schaibly, J.H.: 1973,<br />
Study of the Sensitivity of Coupled<br />
Reaction Systems to Uncertainties in<br />
Rate Coefficients. I. Theory Z Chem.<br />
Phys. 59, 3873-3878.<br />
| | Demiralp, M., and Rabitz, H.: 1981,<br />
Chemical Kinetic Functional Sensitivity<br />
Analysis: Elementary Sensitivities,<br />
J. Chem. Phys. 74, 3362-3375.<br />
| | Downing, D.J., Gardner, R.H., and<br />
Hoffman, EO.: 1985, An Examination of<br />
Response-Surface Methodologies for<br />
Uncertainty Analysis in Assessment<br />
Models, Technometrics. 27, 151-163.<br />
| | Draxler, R.R., and G.D. Hess, 1997:<br />
Description of the HYSPLIT_4 modeling<br />
system. NOAA Tech. Memo. ERL<br />
ARL-224, NOAA Air Resources<br />
Laboratory, Silver Spring, MD, 24 pp.<br />
| | Draxler, R.R., Stunder, B., Rolph, G., and<br />
Stein, A., Taylor, A., Hysplit4 Users<br />
Guide, 2012.<br />
| | Eckerman, K., F., Ryman, J., C., Federal<br />
Guidance Report No. 12 External<br />
Exposure to Radionuclides in Air, Water<br />
and Soil, 1993.<br />
| | Environmental Modelling for Radiation<br />
Safety (EMRAS) Programme, The<br />
Chernobyl I-131 Release: Model<br />
Validation and Assessment of the<br />
Countermeasure Effectiveness: Report<br />
of the Chernobyl 131-I Release Working<br />
Group of EMRAS Theme 1.<br />
| | EUR-18825, FZKA-6311, ISBN 92-894-<br />
2085-5, European Communities 2001<br />
Probabilistic Accident Consequence<br />
Uncertainty Assessment Using COSYMA:<br />
Uncertainty from the Dose Module.<br />
| | EUR-18826, FZKA-6312, ISBN- 92-894-<br />
2088-X, European Communities 2001<br />
Probabilistic Accident Consequence<br />
Uncertainty Assessment Using COSYMA:<br />
Overall Uncertainty Analysis.<br />
| | Eyüpoğlu, F., Türkiye topraklarının<br />
verimlilik durumları, 1999.<br />
| | Gardner, R.H.: Huff, D.D., O'Neill, R.V.,<br />
Mankin, J.B., Carney, J. and Jones, J.:<br />
1980, Application of Error Analysis to a<br />
Marsh Hydrology Model, Water<br />
Resources Res. 16, 659-664.<br />
| | Gardner, R.H., O'Neill, R.V., Mankin, J.B.<br />
and Carney, J.H.: 1981, A Comparison<br />
of Sensitivity Analysis and Error Analysis<br />
Based on a Stream Ecosystem Model,<br />
Ecol. Modelling. 12, 173- 190.<br />
| | Garger, E.K., Hoffman, F.O., Thiessen,<br />
K.M., Uncertainty of the long-term<br />
resuspension factor, Atmos. Environ. 31<br />
(1997) 1647–1656.<br />
| | Health Canada, Recommendations on<br />
Dose Coefficients for Assessing Doses<br />
from Accidental Radionuclide Releases<br />
to the Environment, 1999.<br />
| | Health Protection Agency, Application<br />
of the 2007 Recommendations of the<br />
ICRP to the UK, 2009.<br />
| | Helton, J.C., Garner, J.W., Marietta,<br />
M.G., Rechard, R.E, Rudeen, D.K. and<br />
Swift, EN.: 1993. Uncertainty and<br />
Sensitivity Analysis Results Obtained in<br />
a Preliminary Performance assessment<br />
for the Waste Isolation Pilot Plant, Nuc.<br />
Sci. and Eng. 114, 286-331.<br />
| | Helton, J.C., Garner, J.W., McCurley, R.D.<br />
and Rudeen, D.K. Sensitivity analysis<br />
techniques and results for performance<br />
assessment at the waste isolation pilot<br />
plant. Albuquerque, NM: Sandia<br />
National Laboratory; Report No.<br />
SAND90-7103, 1991.<br />
Research and Innovation<br />
Design and Development of a Radio eco logical Domestic User Friendly Code for Calculation of Radiation Doses and Concentration due to Airborn Radio nuclides Release<br />
A. Haghighi Shad, D. Masti, M. Athari Allaf, K. Sepanloo, S.A.H. Feghhi and R. Khodadadi
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
Authors<br />
A. Haghighi Shad<br />
PhD in Nuclear Energy Eng<br />
Department of Nuclear Eng.<br />
Science and Research Branch<br />
of Islamic Azad University<br />
Tehran, Iran<br />
D. Masti<br />
Assistant of Prof. Azad University<br />
of Boushehr<br />
Boushehr NPP<br />
Manager of Research and<br />
Development in BNPP-1<br />
M. Athari Allaf<br />
Assistant of Prof.<br />
Department of Nuclear Eng.<br />
Science and Research Branch<br />
of Islamic Azad University<br />
Tehran, Iran<br />
K. Sepanloo<br />
Associate of Prof. Reactor and<br />
nuclear safety school<br />
Nuclear Science and Technology<br />
Research Institute (NSTRI)<br />
Tehran, Iran<br />
S.A.H. Feghhi<br />
Prof. Shahid Beheshti University<br />
of Tehran<br />
Department of Nuclear Eng.<br />
Deputy Manager of execution and<br />
Research in Nuclear Eng. Faculty<br />
Tehran, Iran<br />
R. Khodadadi<br />
Consultant<br />
Science and Research Branch<br />
of Islamic Azad University<br />
Tehran, Iran<br />
121<br />
EVENTS<br />
Event Report: Vertiefungskurs 2017:<br />
Zukunftsmanagement – zentrale<br />
Lösungsansätze für Kernanlagen<br />
Matthias Rey<br />
Zukunftsmanagement erfordert sorgfältige Planung und Wissen darüber, welche Optionen zur Verfügung<br />
stehen, wieweit Optimierungen sinnvoll sind und welche Maßnahmen und Prozessänderungen sich allenfalls bereits<br />
anderswo bewährt haben. Der Vertiefungskurs 2017 des Nuklearforums Schweiz nahm diese Thematik auf. Im Zentrum<br />
standen am ersten Kurstag Lösungsansätze zum Optimieren von Systembetrieb und Instandhaltung. Am zweiten Tag<br />
standen die Mitarbeitenden in seiner sich verändernden Umwelt im Fokus. Als Novum wurden dieses Jahr an beiden<br />
Nachmittagen die Themen der Inputreferate des Vormittags in Workshops vertieft diskutiert.<br />
Der neue Präsident der Kommission<br />
für Ausbildungsfragen des Nuklearforum<br />
Schweiz, Thomas Kohler,<br />
begrüßte die Teilnehmenden und<br />
wies auf das neue Format mit den<br />
Workshops hin, das aufgrund der<br />
Feedbacks zu vergangenen Kursen<br />
eingeführt worden ist.<br />
Optimierung von Systembetrieb<br />
und Instandhaltung<br />
In der Einleitung zum ersten Block<br />
wies Andreas Pfeiffer, Leiter des Kernkraftwerks<br />
Leibstadt, darauf hin, dass<br />
in der Schweiz bald das letzte KKW<br />
im deutschsprachigen Raum stehen<br />
dürfte. Die Betreiber stünden unter<br />
Druck seitens der Politik, müssten ihre<br />
Koten optimieren und sähen sich<br />
mit einer schrumpfenden Lieferantenbasis<br />
konfrontiert.<br />
Wie die ABB ihre Lieferanten<br />
bewirtschaftet legte Nikolaus Gäbler,<br />
Head of Supply Chain Management<br />
der Business Unit Grid Automation,<br />
dar. In der Schweiz gibt es ihm zufolge<br />
praktisch nur noch hoch spezialisierte<br />
Anbieter. Zudem sei die Supply<br />
Chain im Servicegeschäft besonders,<br />
charakterisiert durch ihre Kurzfristigkeit,<br />
wenig Beständigkeit und viele<br />
Sonderwünsche. Damit „die linke<br />
Hand genau weiss, was die rechte<br />
tut“, habe die ABB weltweit ein<br />
IT-Tool für das Lieferantenmanagement<br />
eingeführt, in das sämtliche<br />
Anfragen und Offerten eingetragen<br />
werden. Um langfristige Partnerschaften<br />
zu schaffen müsse man auch<br />
das Zwischenmenschliche berücksichtigen<br />
und sich manchmal mit<br />
Lieferanten treffen, ohne dass dabei<br />
gleich ein Geschäft entsteht. Um<br />
Kosten und Prozesse zu optimieren<br />
oder Abhängigkeiten zu reduzieren,<br />
kommt laut Gäbler vor, dass die ABB<br />
einen Lieferanten gleich komplett<br />
übernimmt.<br />
Im zweiten Referat zum Thema<br />
Reverse Engineering zeigte Florian<br />
Kanoffsky von der KSB AG auf, was ein<br />
Unternehmen tun kann, wenn seine<br />
Ersatzteile nicht mehr geliefert<br />
werden. Wenn sich kein anderer<br />
Lieferant findet und der Austausch der<br />
entsprechenden Komponenten keine<br />
Option ist, können Teile nachgebaut<br />
werden, was dann eben als «Reverse<br />
Engineering» bezeichnet wird.<br />
Kanoffsky beschrieb den typischen<br />
Ablauf solcher Aufträge von der<br />
Vermessung über das Erstellen von<br />
3D- und Guss-Modellen bis zur<br />
Endbear beitung. Bei der Planung<br />
müsse gerade in der Nuklearbranche<br />
den Genehmigungsprozessen, der<br />
Zeich nungsfreigabe sowie den Prüfungen<br />
und Abnahmen genug Zeit<br />
| | Vertiefungskurs 2017, wie gewohnt im Hotel Arte in Olten<br />
beige messen werden. Auch rechtliche<br />
Aspekte wie Patente und allenfalls<br />
Geheimhaltungsklauseln für Zeichnungen<br />
und Pläne in bestehenden<br />
Verträgen gelte es unbedingt zu<br />
beachten.<br />
Theoretische Ansätze,<br />
Fallstudien und Erfahrungsberichte<br />
Mit dem Referat von Giovanni<br />
Sansavini vom Reliability and Risk<br />
Engineering Laboratory der ETH Zürich<br />
zu Importance Measures ging es<br />
anschließend von der Praxis in die<br />
Theorie. Importance Measures quantifizieren<br />
die Bedeutung von Komponenten<br />
oder Ereignissen bei der<br />
Beurteilung der Systemperformance.<br />
Sie seien eine große praktische Hilfe<br />
für Systemdesigner und -manager,<br />
Events<br />
Event Report: Nuklearforum Schweiz – Future Management – Key Solutions for Nuclear Facilities ı Matthias Rey
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
122<br />
EVENTS<br />
da sie Schwachstellen im System<br />
aufzuspüren helfen und Richtlinien<br />
für die Verbesserung liefern.<br />
Danach ging es wieder in Richtung<br />
Praxis, genau gesagt zur Probabilistischen<br />
Sicherheitsanalyse (PSA)<br />
in KKW. Dusko Kancev, Fachverantwortlicher<br />
PSA Modellentwicklung<br />
und Sicherheitsindikatoren des Kernkraftwerks<br />
Gösgen, zeigte anhand<br />
einer PSA-Fallstudie, wie in KKW die<br />
Überwachungsanforderungen unter<br />
Berücksichtigung der Ausrüstungsalterung<br />
optimiert werden können.<br />
Mit dem verwendeten Modell kann<br />
die Alterung von Komponenten<br />
explizit, und nicht wie bei der<br />
„ traditionellen“ PSA stationär, dargestellt<br />
und letztendlich die Überwachungsintervalle<br />
der untersuchten<br />
Komponenten optimiert werden.<br />
Mit dem letzten Vortrag vor der Mittagspause<br />
folgte dann der erste, am<br />
Vertiefungskurs mittlerweile traditionelle<br />
Blick über den Tellerrand.<br />
Ronald Meier, Sektionsleiter Technische<br />
Organisation Zürich des Bundesamts für<br />
Zivilluftfahrt, stellte optimierte Instandhaltungsstrategien<br />
für den Langzeitbetrieb<br />
vor. Er ging auf Aspekte wie<br />
Ersatzteilstrategien und Lagerhaltung<br />
ein. Punkto Ersatzteile zahlen sich<br />
große Flotten des gleichen Flugzeugtyps<br />
sowie die Zusammenarbeit mit<br />
anderen Fluggesellschaften aus. Auch<br />
bei der Lagerhaltung spielt das sogenannte<br />
Pooling eine zunehmende<br />
Rolle, ebenso das Auslagern von<br />
Ersatzteillagern und die Tendenz zu<br />
zentralen größeren Lagern und nur<br />
kleinen Lagern vor Ort. Sowohl bei der<br />
Diversifizierung der Zulieferer als auch<br />
bei Reparaturen durch Eigenpersonal<br />
sind Überprüfungen und Zulassungen<br />
durch die Behörden nötig. Dass auch<br />
die Ausbildung streng reguliert ist und<br />
entsprechend lange dauert, führt zusammen<br />
mit eher kleinen Löhnen bei<br />
großer Verantwortung zu gewissen<br />
Nachwuchsproblemen in der Flugzeuginstandhaltung.<br />
Ein weiteres<br />
Problem stellen gefälschte oder nicht<br />
zugelassene Ersatzteile dar.<br />
Diskussion in Gruppen<br />
Am Nachmittag fand dann die besagte<br />
Premiere mit vier zeitgleich laufenden<br />
Workshops statt, für die sich die Teilnehmenden<br />
im Vorfeld angemeldet<br />
hatten. Eine Gruppe beschäftigte<br />
sich mit der Frage, was verlängerte<br />
Betriebszyklen für die Instandhaltung<br />
bedeuten. Lagerhaltung<br />
und Bestellkontrakte: vorbeugende<br />
Instandhaltung oder ‹run to<br />
failure›? lautete das Thema des<br />
zweiten Workshops. Die dritte Gruppe<br />
| | Diskussion im Workshop... | | ... und Präsentation im Plenum<br />
befasste sich mit der System Health<br />
und Systemzustandsberichten hinsichtlich<br />
des Kostenoptimierungspotenzials.<br />
Im vierten Workshop<br />
ging es um Möglichkeiten der Wertschöpfung<br />
und Belastungen der<br />
technischen Systeme, die der<br />
Lastfolge betrieb von KKW mit sich<br />
bringen kann. Der erste Kurstag<br />
endete mit der Präsentation der<br />
Resultate aus den einzelnen Workshops<br />
unter der Leitung von Michael<br />
Dost, Leiter des Kernkraftwerks<br />
Beznau, endete der erste Kurstag.<br />
Kompetenzanpassung<br />
und -transfer<br />
Den zweiten Tag des Vertiefungskurses<br />
eröffnete Martin Saxer, Leiter<br />
des Kernkraftwerks Mühleberg, mit<br />
dem Hinweis auf die Bedeutung der<br />
Menschen und ihrer Kompetenzen<br />
für das Zukunftsmanagement. Das<br />
erste Referat von Frank Sommer,<br />
Senior Vice President, Center of Competence<br />
Operations der PreussenElektra<br />
GmbH, erläuterter die Herausforderungen<br />
und Erfahrungen bei<br />
organisatorischen Veränderungen.<br />
Sommer erläuterte, wie der Energiekonzern<br />
E.ON entstanden ist und wie<br />
daraus letztlich die PreussenElektra<br />
hervorging. Er beleuchtete die Auswirkungen<br />
großer organisatorischer<br />
Veränderungen und Neuausrichtungen<br />
auf die Mitarbeitenden. In<br />
der Vergangenheit habe die große<br />
Herausforderung in der Integration<br />
von Kraftwerken etablierter Unternehmen<br />
aus verschiedenen Ländern<br />
in ein Großunternehmen bestanden.<br />
Dagegen stehe heute der Erhalt der<br />
Kompetenz für den sicheren Betrieb<br />
der Anlagen bis zur Stilllegung im<br />
Fokus. Um Sicherheit für die Mitarbeitenden<br />
zu erreichen und einen<br />
wirtschaftlichen Rückbau sicherzustellen<br />
sei es enorm wichtig, Nachbetrieb<br />
und Rückbau frühzeitig zu<br />
planen. Die Entwicklung eines internationalen<br />
Geschäfts schaffe in<br />
diesem Zusammenhang Perspektiven<br />
für die Belegschaften.<br />
Der darauf folgende Vortrag von<br />
Christer Johansson, Deputy Director<br />
Maintenance der Forsmarkskraftgrupp<br />
AB bei Vattenfall, stand unter ganz<br />
anderen Vorzeichen, da er von Strategien<br />
zur Laufzeitverlängerung<br />
handelte. Neben Strategien bei der<br />
Instandhaltung ging Jonansson vertieft<br />
auf den Kompetenzerhalt beim<br />
Personal ein. In Forsmark wird zum<br />
Beispiel wo immer möglich jüngeres<br />
Personal mit weniger Erfahrung<br />
zusammen mit langjährigeren Mitarbeitenden<br />
eingesetzt, oft auch unter<br />
Miteinbezug von Lieferanten. Darüber<br />
hinaus sei das Vorhandensein von<br />
Designregeln, Komponentenspezifikationen,<br />
Testergebnissen und weiterer<br />
Dokumentationen sowie das Wissen,<br />
wie die Komponenten im System<br />
funktionieren, Grundvoraussetzung<br />
für den Kompetenzerhalt.<br />
Know-how-Management und<br />
Know-why-Management in der<br />
Nuklearindustrie lautete der Titel<br />
des Beitrags von Tomas Hahn, Vice<br />
President Products and Projects der<br />
Areva GmbH. Die aktuelle wirtschaftliche<br />
Lage der europäischen<br />
Energieindustrie führt laut Hahn zu<br />
einem immer geringeren Volumen<br />
an Engineering- Aufgaben. Die neuen<br />
Schwerpunkte lägen beim Lebensdauer<br />
management und Modernisierungen,<br />
der Erhöhung von Sicherheitsstandards<br />
sowie der Weiterentwicklung<br />
des Stands von Wissenschaft<br />
und Technik. Die langen Laufzeiten<br />
von Kernkraftwerken bedingen den<br />
Transfer von Know-how von einer<br />
Generation von Ingenieuren zur<br />
nächsten. Daneben sei auch das Knowwhy-Training<br />
von großer Bedeutung,<br />
also die Vermittlung von Basis hintergrund<br />
wissen wie bestimmte Anlagen-<br />
Designs, Sicherheitskonzepte mit den<br />
Forderungen nach Redun danzen,<br />
Standards etc. und nicht zuletzt die<br />
Interaktion zwischen den verschiedenen<br />
Reaktorsystemen. Damit seien<br />
die Voraussetzungen gegeben, um<br />
komplexe technische Fragestellungen<br />
in einem anspruchsvollen Genehmigungsumfeld<br />
unter schwierigen<br />
Markt bedingungen professionell zu<br />
bearbeiten und die Bedürfnisse der<br />
Kunden zu befrie digen.<br />
Events<br />
Event Report: Nuklearforum Schweiz – Future Management – Key Solutions for Nuclear Facilities ı Matthias Rey
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
Sinkende Verfügbarkeit<br />
und steigender Bedarf<br />
Auf die Bedeutung des Kompetenzmanagements<br />
für die Aufsicht angesichts<br />
der aktuellen Entwicklungen in<br />
der Kerntechnik ging anschließend<br />
Holger Knissel, Fachspezialist Mensch<br />
und Organisation beim Eidgenössischen<br />
Nuklearsicherheitsinspektorat<br />
(Ensi), ein. In der Nuklearindustrie<br />
stehe aktuell eine sinkende Kompetenzverfügbarkeit<br />
einem steigenden<br />
Bedarf gegenüber. Gründe für die<br />
sinkende Verfügbarkeit sind der<br />
Generationswechsel in den Betriebsorganisationen,<br />
die wegen der politischen<br />
Randbedingungen abnehmende<br />
Attraktivität die zu Rekrutierungsproblemen<br />
führt, sowie der<br />
Kostendruck aufgrund der wirtschaftlichen<br />
Lage. Auf der anderen Seite<br />
nehme der Kompetenzbedarf zu, weil<br />
das Spektrum an benötigten Kompetenzen<br />
aufgrund der technologischen<br />
Entwicklungen immer breiter wird,<br />
weil die Alterung der Anlagen neue<br />
Fragestellungen aufwirft und weil der<br />
Support der Zulieferer abnimmt.<br />
Daraus folgerte Knissel, dass eine<br />
Kompetenzlücke zu entstehen droht.<br />
Dem könne und müsse mit aktivem<br />
Kompetenzmanagement entgegengewirkt<br />
werden.<br />
Der nächste Beitrag stellte einen<br />
weiteren Ausflug in die Aviatik dar:<br />
Nutzbarmachen von Erfahrungen<br />
aus ‹near misses› von Stefan Oser,<br />
Leiter Technical Training der Swiss International<br />
Air Lines Ltd. Er ging unter<br />
anderem der Frage nach, wie ein<br />
gesundes und vernünftiges Maß an Anleitungen,<br />
Checklisten und sonstiger<br />
Dokumentation für Instandhaltungsund<br />
Reparaturarbeiten aussieht und<br />
wie man die Leute dazu bringt, Vorkommnisse<br />
und Ab weichungen zu<br />
melden. Anhand von Erlebnissen aus<br />
seiner persönlichen Karriere legte er<br />
dar, wie wichtig lebenslanges Lernen,<br />
insbesondere aus Fehlern, ist.<br />
Freiheit der Forschung<br />
gewährleistet<br />
Für das letzte Inputreferat des diesjährigen<br />
Vertiefungskurses zeigte<br />
Horst-Michael Prasser von der ETH<br />
Zürich auf, was für den langfristigen<br />
Kompetenzerhalt in der Schweiz<br />
nötig ist. Er betonte eingangs, dass<br />
das neue Energiegesetz keine Einschränkungen<br />
für die Nuklearforschung<br />
beinhalte und das die Freiheit<br />
der Forschung gewährleistet sei. Auch<br />
gebe es keine spezifischen Budgetkürzungen<br />
für die Nuklearforschung<br />
am Paul Scherrer Institut PSI und die<br />
Professuren an den eidgenössischen<br />
Hochschulen. Weiter brauche es<br />
Kompetenzerhalt und Kompetenzentwicklung<br />
bei Kerntechnikern, angehenden<br />
Kerntechnikern sowie auch<br />
Kernenergiegegnern, denn ein profunder<br />
Disput über Kerntechnik sei<br />
eine objektive Notwendigkeit unserer<br />
Zeit. Offene, proaktive Kommunikation<br />
auch zu Problemen sei unerlässlich,<br />
ebenso wie breit angelegte<br />
Forschung und Bildung.<br />
| | Horst-Michael Prasser :«Ein profunder<br />
Disput über Kerntechnik ist eine objektive<br />
Notwendigkeit unserer Zeit.»<br />
Am Nachmittag beschäftigten sich<br />
drei Workshop-Gruppen unter der<br />
Leitung von Vertretern der Kernkraftwerke<br />
Gösgen, Mühleberg und<br />
Leibstadt mit der Frage nach dem<br />
richtigen Maß beim Erkennen und<br />
Melden von Befunden. Der vierte<br />
Workshop thematisierte den Kulturwandel<br />
und den Umgang mit Multinationalität<br />
in Kernkraftwerken. Die<br />
Ergebnisse wurden ebenfalls wieder<br />
im Plenum präsentiert und diskutiert,<br />
dieses Mal moderiert von Herbert<br />
Meinecke, dem Leiter des Kernkraftwerks<br />
Gösgen. Der Geschäftsführer<br />
des Nuklearforums, Beat Bechtold, verabschiedete<br />
anschließend die Teilnehmenden<br />
des Vertiefungskurses<br />
mit dem Hinweis, dass dieser von nun<br />
an voraussichtlich im Zweijahres-<br />
Rhythmus stattfindet.<br />
Author<br />
Matthias Rey<br />
Nuklearforum Schweiz /<br />
Forum nucléaire suisse<br />
Frohburgstrasse 20<br />
4600 Olten, Switzerland<br />
123<br />
KTG INSIDE<br />
Inside<br />
KTG: Wichtige Terminhinweise<br />
in eigener Sache<br />
Ankündigungen zum Vortag unserer diesjährigen Jahrestagung,<br />
dem 49 th Annual Meeting on Nuclear Technology<br />
(AMNT <strong>2018</strong>) vom 29. bis 30. Mai <strong>2018</strong> im Estrel-Hotel,<br />
Berlin:<br />
33<br />
KTG-Mitgliederversammlung<br />
• Wann? Montag, 28. Mai <strong>2018</strong>, 16.00 Uhr<br />
• Wo? Estrel Convention Center, Raum IV<br />
(2. OG), Sonnenallee 225, 12057 Berlin<br />
33<br />
Verleihung des Karl-Wirtz-Preises<br />
• Wann? Montag, 28. Mai <strong>2018</strong>, 18.00 Uhr<br />
• Wo? Estrel Convention Center, Raum IV<br />
(2. OG), Sonnenallee 225, 12057 Berlin<br />
33<br />
Get-together der KTG (auch für Nicht-Mitglieder)<br />
• Wann? Montag, 28. Mai <strong>2018</strong>, 19.00 Uhr<br />
• Wo? Estrel Convention Center, Leaf,<br />
Sonnenallee 225, 12057 Berlin<br />
KTG Fachgruppe Thermo- und<br />
Fluiddynamik<br />
Die KTG Fachgruppe Thermo- und Fluiddynamik<br />
beschäftigt sich mit<br />
• der Entwicklung, Validierung und Anwendung von<br />
Methoden und Computerprogrammen zur Berechnung<br />
von Strömungsvorgängen im Reaktorkühlkreislauf<br />
(RKL) sowie dem Containment,<br />
• der zur Validierung der Rechenmethoden erforderlichen<br />
Experimente einschließlich der Entwicklung von<br />
Messtechniken sowie<br />
• der Bestimmung von analytischen sowie experimentellen<br />
Unsicherheiten.<br />
Methoden, Computerprogramme und Experimente werden<br />
u.a. in kerntechnischen Verfahren genutzt, um Nachweise<br />
zu führen (Hersteller und Betreiber) oder unabhängig zu<br />
prüfen (Behörden und Gutachter) und die Einhaltung<br />
von Anforderungen aus dem kerntechnischen Regelwerk<br />
aufzuzeigen. Aktuelle Themen, die derzeit im Fokus der<br />
Fachgruppe stehen, sind die Weiterentwicklung und Validierung<br />
von eindimensionalen Systemcodes zur Simulation<br />
KTG Inside
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
124<br />
KTG INSIDE<br />
von innovativen Reaktorkonzepten mit passiven Sicherheitsmerkmalen,<br />
die Ertüchtigung von Computational Fluid<br />
Dynamic (CFD) Methoden zur Berechnung mehrphasiger<br />
Strömungszustände, die Entwicklung von Methoden zur<br />
Durchführung von Sensitivitäts- und Unsicherheitsanalysen<br />
für CFD Analysen. Des Weiteren werden aktuelle Fragestellungen<br />
zur technisch-wissenschaftlichen Absicherung<br />
des ver bleibenden Betriebs deutscher Kernkraftwerke und<br />
Forschungsreaktoren in der Fachgruppe aufgegriffen.<br />
Hierzu zählen u.a. Themen wie die mögliche Beeinträchtigung<br />
der Kernkühlung durch Isoliermaterial und oder<br />
Zinkboraten oder das sog. Neutronenflussrauschen.<br />
Der Vorstand der Fachgruppe, die derzeit um die 200<br />
Mitglieder besitzt, besteht derzeit aus 5 Personen. Dies sind<br />
Dr.-Ing. Andreas Schaffrath (Gesellschaft für Anlagen- und<br />
Reaktorsicherheit) gGmbH, der aktuell der Sprecher der<br />
Fachgruppe ist, Dipl.-Ing. Sören Alt (Hochschule Zittau,<br />
Görlitz), Dr.-Ing. Ingo Ganzmann (AREVA GmbH) und Prof.<br />
Dr.-Ing. Eckhart Laurien (IKE Stuttgart). Kassenwart und<br />
Kommunikationsbeauftragter der Fachgruppe ist Dr.-Ing.<br />
Jürgen Sydow (TÜV NORD Systems GmbH). Die Fach gruppe<br />
arbeitet – sofern dies thematisch erforderlich ist – interdisziplinär<br />
mit anderen Fachgruppen der KTG zusammen und<br />
organisiert z.B. gemeinsame Fach sitzungen auf dem jährlich<br />
stattfindendem Annual Meeting on Nuclear Technology<br />
(AMNT), KTG Fachtage oder Vortragsveranstaltungen. Die<br />
KTG Fachgruppe Thermo- und Fluiddynamik aktualisiert<br />
kontinuierlich ihren Internetauftritt.<br />
Die letzte große Veranstaltung der Fachgruppe war der<br />
Ende 2016 in Karlsruhe zusammen mit den Fachgruppen<br />
Reaktorphysik und Berechnungsmethoden und Reaktorsicherheit<br />
durchgeführte, 2-tägige Fachtag zu Aktuellen<br />
Themen der Reaktorsicherheit. Thematische Schwerpunkte<br />
des Fachtages waren neue Erkenntnisse aus den Bereichen<br />
Neutronenphysik, Anlagenbetrieb, BE-Lagerbecken, sowie<br />
Sensitivität, Entwicklung und Validierung von Codes<br />
sowie Tools zur Berechnung von Unsicherheiten und<br />
Sensitivitäten. Abgerundet wurde der Fachtag durch einen<br />
geselligen Abend. Der Fachtag war mit über 60 Teilnehmern<br />
gut besucht. Über den Fachtag wurde in der <strong>atw</strong><br />
(International Journal for Nuclear Power, Heft 10, 2016)<br />
sowie der Kerntechnik (Heft 5, 2016) berichtet. Darüber<br />
hinaus wurden diverse Beiträge des Fachtages im Heft 3,<br />
2017 der Kerntechnik veröffentlicht.<br />
Aktuell engagieren sich zahlreiche Mitglieder substantiell<br />
an der Vorbereitung des AMNT <strong>2018</strong>. Sie sind u.a. im<br />
Programmausschuss oder verschiedenen Auswahlausschüssen<br />
vertreten. Die Fachgruppe hat u.a. die Fokussitzung<br />
Safety of Advanced Nuclear Power Plants vor bereitet,<br />
in der zunächst ausgewählte Experten über aktuelle kerntechnische<br />
Entwicklungen in UK und China berichten. Es<br />
folgt dann ein Vortrag über eine Initiative der OECD/NEA<br />
zur Untersuchung und Bewertung thermohydraulischer<br />
Aspekte sog. passiver Sicherheitssysteme. Im Anschluss<br />
wird dann ein Vertreter des Bundesministeriums für<br />
Wirtschaft und Energie (BMWi) eine Übersicht über die<br />
derzeit in Deutschland durchgeführten Arbeiten im Bereich<br />
der Reaktorsicherheitsforschung geben. Es folgen abschließend<br />
zwei Vorträge, in denen herausragende BMWi<br />
finanzierte Forschungsarbeiten zu experimentellen und<br />
analytischen Untersuchungen passiver Systeme zur Beherrschung<br />
von Auslegungsstörfällen vorgestellt werden.<br />
Zusätzlich wurden bereits für die technischen Sitzungen<br />
des Key Topic Outstanding Know-How & Suitainable<br />
Innovations die eingereichten Abstracts gereviewt.<br />
Für das Jahr <strong>2018</strong> ist bereits – neben den üblichen<br />
Aktivitäten zur Vorbereitung des AMNT 2019 – zusammen<br />
mit der Sektion Süd eine Vortragsveranstaltung bei der<br />
Gesellschaft für Anlagen- und Reaktorsicherheit (GRS)<br />
gGmbH zu dem Thema Erweiterung der GRS Rechenkette<br />
für fortschrittliche Reaktoren geplant.<br />
Zu allen zuvor genannten Aktivitäten hoffen wir auf<br />
eine rege Teilnahme.<br />
Dr.-Ing. Andreas Schaffrath<br />
Sprecher der KTG Fachgruppe Thermo- und Fluiddynamik<br />
Kernfusion: Eine kleine Fachgruppe<br />
für ein Thema mit viel Zukunft<br />
Die Fachgruppe Kernfusion der KTG wurde erst 1997<br />
gegründet, also zu einer Zeit, als die KTG bereits 28 Jahre<br />
alt war. Derzeit hat sie 60 Mitglieder. Ihre thematischen<br />
Schwerpunkte liegen auf Fusionstechnologie und Plasmaphysik.<br />
Der Gründer und erste Sprecher der Fachgruppe war Dr.<br />
Gert Spannagel (FZK). Der Staffelstab wurde 20<strong>02</strong> weitergegeben<br />
an Michael Gehring (Babcock Noell), der ihn über<br />
10 Jahre lang hochhielt. Ich selbst erhielt ihn dann 2013.<br />
Obwohl die Fachgruppe Kernfusion in der KTG von<br />
Anfang an eine etwas kleinere Fachgruppe war, hat sie<br />
doch immer wieder durch ihre Aktionen und ihre Präsenz<br />
auf der Jahrestagung munter zum Leben und Programm<br />
der KTG beigetragen. In vielen Technischen und Fach-<br />
Sitzungen auf den Jahrestagungen verfolgte und kommunizierte<br />
sie die Weiterentwicklung der Kernfusionstechnologie<br />
und machte von Anfang an klar, dass Kerntechnik<br />
eben mehr ist als die technische Beherrschung der Kernspaltung.<br />
Zu den Highlights der Vergangenheit gehörte<br />
sicherlich auf der JK 2007 der Plenarvortrag von Kaname<br />
Ikeda, damals erster „Director-General“ des ITER-Projekts.<br />
Auch in jüngerer Vergangenheit wurden interessante<br />
Aktivitäten entwickelt. So konnten wir 2016 Prof. Robert<br />
Wolf für einen Plenarvortrag auf der AMNT zum Thema<br />
Wendelstein 7-X gewinnen. Der W7X hatte erst wenige<br />
Monate zuvor sein erstes Plasma gesehen und gezeigt, dass<br />
er über ein nahezu perfektes Magnetfeld verfügt. Und<br />
2017 organisierten wir im Anschluss an die AMNT eine<br />
Exkursion nach Greifswald, um uns diesen W7X mal selbst<br />
anzusehen. Dass dabei Dr. Spannagel zu den Expeditionsteilnehmern<br />
gehörte, hat mich besonders gefreut. Vor Ort<br />
in Greifswald gab uns Prof. H.-S. Bosch einen umfassenden<br />
Einblick in die Besonderheiten des W7X, seine Inbetriebnahme,<br />
über die Ergebnisse der ersten Betriebsphase<br />
und die Pläne zum weiteren Projektverlauf. Anschließend<br />
erklärte uns Dr.-Ing. L. Wegener die Besonderheiten<br />
und Herausforderungen des W7X-Projekts hinsichtlich<br />
Konstruktion, Organisation und Projektmanagement. So<br />
waren wir schon vor der eigentlichen Führung beeindruckt<br />
und sensibilisiert für das, was wir anschließend auch aus<br />
der Nähe zu sehen bekamen.<br />
Neben den Aktionen und dem „Blick über den Tellerrand“<br />
der Kernspaltungstechnik, den wir bieten, stellt<br />
unsere Fachgruppe aber auch einen Link dar zu anderen<br />
Fusions-orientierten Körperschaften wie den deutschen<br />
Fusionslaboren (IPP, KIT und FZJ), dem deutschen ITER<br />
Industrie Forum (dIIF), dem Europäischen Fusion Industry<br />
Innovation Forum (FIIF) und anderen.<br />
Und was wir in der Zukunft vorhaben? Schließen Sie<br />
sich unserer Fachgruppe an und wünschen Sie sich etwas!<br />
Dr. Thomas Mull<br />
Sprecher der KTG Fachgruppe Kernfusion<br />
KTG Inside
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
KTG-Sektion Ost:<br />
Exkursion<br />
Die KTG-Exkursion 2017 der Sektion Ost führte uns in das<br />
mitteldeutsche Braunkohlegebiet zur MIBRAG südlich von<br />
Leipzig. Die erste Station war das Braunkohlekraftwerk<br />
Deuben mit der angeschossenen Brikettfabrik. Das Kraftwerk<br />
stammt aus den 1930er Jahren. Der erste Eindruck<br />
des Kraftwerkskomplexes überraschte uns mit der gelungenen<br />
Architektur der erhaltenen Industrie gebäude in Ziegelbauweise.<br />
Nach dem Besuch des Leitstandes konnten<br />
wir im Kraftwerksgebäude in einen stillgelegten Braunkohle-Feuerungskessel<br />
einsteigen und erhielten anschaulich<br />
einen Einblick in die Funktionsweise und die technischen<br />
Herausforderungen des Kraftwerks. Beim anschließenden<br />
Rundgang durch den Generatorsaal erfuhren wir,<br />
dass ein Großteil der erzeugten Energie für die Großgeräte<br />
des angeschlossenen Tagebaus und für den Transport der<br />
Braunkohle mit Förderbändern und E-Loks benötigt wird.<br />
Leider konnte die geplante Besichtigung der Brikettfabrik<br />
wegen eines Stillstandes nicht stattfinden.<br />
freigesetzten elementaren Quecksilbers führte zum<br />
Auftragseingang. Heute werden unter anderem quecksilberhaltige<br />
Schlämme und Rückstände mit natürlicher<br />
Radioaktivität behandelt. Diese Rückstände in Form<br />
von Schlämmen entstehen beispielsweise bei der Erdgasförderung.<br />
Die Schlämme werden thermisch behandelt<br />
und dabei Quecksilber gewonnen, das dann hochrein<br />
vermarktet wird. Die Rückstände mit natürlicher Radioaktivität<br />
werden immobilisiert und auf spezielle Deponien<br />
verbracht. Bei einem Rundgang durch die Produktionshallen<br />
wurden uns anschaulich die Technologien beim<br />
Metallrecycling erläutert.<br />
Mit vielen neuen Eindrücken, die auf uns in den zwei<br />
Tagen einwirkten, haben wir dann die Heimreise angetreten.<br />
Besonderer Dank geht an die Mitarbeiter der beiden<br />
Firmen für die intensive und offene Betreuung während<br />
der Führungen.<br />
B. Standfuß et al.<br />
Zwischen Forschung, Rückbau<br />
und Entsorgung – aktuelle Aufgaben<br />
in der Kerntechnik<br />
125<br />
KTG INSIDE<br />
| | KTG-Sektion Ost: Exkursion 2017<br />
Im Tagebau Profen konnten wir uns von der Besucherplattform<br />
aus einen Überblick über die Ausmaße des<br />
Tagebaus verschaffen. Am Nachmittag fuhren wir dann<br />
zum Tagebau Schleenhain. Nach dem Besuch der Kaue und<br />
des Leitstandes des Tagebaues fuhren wir im Besucherbus<br />
im Tagebau direkt bis an die Schaufelradbagger, die Eimerkettenbagger<br />
und die kilometerlangen Bandanlagen. Es<br />
wurde erläutert, dass die Sanierung der Tagebauflächen<br />
nach der Verfüllung noch sechs Jahre vom Tagebauunternehmen<br />
durchgeführt wird. Mehrere Anpflanzungen und<br />
Fruchtfolgen garantieren, dass danach das Gelände wieder<br />
mit hoher Ackerzahl landwirtschaftlich ertragreich<br />
genutzt werden kann. In Gesprächen mit MIBRAG-<br />
Mitarbeitern wurde von diesen die technikfeindliche<br />
Einstellung von zunehmenden Teilen der Gesellschaft<br />
bedauert, die bei der Einstellung des Braunkohlentagebaus<br />
allein in Mitteldeutschland mehrere zehntausend<br />
Arbeitsplätze kosten würde.<br />
Mit einem geselligen Abend und Diskussionen,<br />
beendeten wir den sehr informativen Tag.<br />
Am nächsten besuchten wir die Gesellschaft für<br />
Metallrecycling Leipzig (GMR) in der Produktionsstätte<br />
Espenhain. Während eines informativen Einführungsvortrages<br />
erhielten wir einen Einblick in die Tätigkeitsfelder<br />
der Firma. Der Ursprung der Firma stammt aus einem<br />
Auftrag zur schadlosen Vernichtung von Munition für<br />
Sturmgewehre der ehemaligen NVA; insbesondere die<br />
Alleinstellung in der BRD mit der Fähigkeit zur Rückhaltung<br />
des bei der Verbrennung von Knallquecksilber<br />
Nachwuchstagung der Jungen Generation<br />
der KTG vom 8. – 10. November 2017<br />
Deutschland war über Jahrzehnte führend in der Entwicklung<br />
der Kerntechnik und dem sicheren und<br />
wirtschaft lichen Betrieb kerntechnischer Anlagen. Seit<br />
dem im Jahr 2011 beschlossenen beschleunigten Ausstieg<br />
aus der Kernenergienutzung ist die Hälfte der Zeit vergangen,<br />
bis das letzte deutsche Kernkraftwerk vom Netz<br />
genommen werden soll.<br />
Knapp 50 Teilnehmer waren der Einladung der Jungen<br />
Generation der KTG zur Nachwuchstagung nach Karlsruhe<br />
gefolgt. Der Campus Nord des Karlsruher Institut<br />
für Technologie (KIT), das frühere Forschungszentrum<br />
Karlsruhe, war seit den 1950er Jahren eine der Hauptstützen<br />
der kerntechnischen Entwicklung Deutschlands.<br />
Viele kerntechnische Forschungsrichtungen mit ihren<br />
Versuchs-, Pilot- und Forschungsanlagen, aber auch Einrichtungen<br />
der kerntechnischen Industrie waren hier<br />
beheimatet, einige sind es bis heute. Wie im restlichen<br />
Land stehen auch hier die Zeichen auf Rückbau – zum<br />
einen, weil einige Anlagen unterdessen das Ende ihrer<br />
Nutzungszeit erreicht haben, zum anderen aber auch,<br />
weil Rückbau, Entsorgung und Endlagerung wichtige<br />
Forschungsthemen sind.<br />
Als Teil der „Energiewende“ wird der anstehende<br />
Rückbau der Kernkraftwerke immer konkreter – Grund<br />
genug, sich direkt bei einem Elektroenergieerzeuger zu<br />
informieren, wie die Unternehmen damit umgehen. Die<br />
Teilnehmer konnten der Einladung in die EnBW-Zentrale in<br />
Karlsruhe folgen, um dort bei einem Get-together in<br />
entspannter Atmosphäre eine kurze Ansprache des<br />
Geschäftsführers der EnBW Kernkraft GmbH, Herrn Jörg<br />
Michels, zu hören. Seinen Worten zufolge hat EnBW den<br />
Rückbau auch seiner noch im Leistungsbetrieb befind lichen<br />
KKW zeitlich und monetär auskömmlich geplant. Er ermunterte<br />
die Teilnehmer ausdrücklich, optimistisch in die<br />
Zukunft zu sehen! Dieser Optimismus fußt auf mehreren<br />
Gründen: Der Rückbau der KKW wird nicht innerhalb einer<br />
Dekade abgeschlossen sein. Weiterhin erwirbt man in<br />
einem Rückbauprojekt Kompetenzen, die sich mühelos auf<br />
KTG Inside
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
126<br />
KTG INSIDE<br />
| | KONRAD-Container am Haken –<br />
Umlagerung im Zwischenlager<br />
der KTE auf dem Campus Nord<br />
| | Der Master-Slave-Manipulator –<br />
was so leicht aussieht, ist dann<br />
doch recht schwer...<br />
Projekte abseits der Kernenergie erzeugung anwenden<br />
lassen – das Lösen ingenieur technischer<br />
Anforderungen sowie enge Termin- und Kostenkontrolle<br />
erfordern alle Projekte, ob innerhalb<br />
oder außerhalb kerntechnischer Anwendungen!<br />
Schlussendlich erhält man innerhalb eines<br />
Rückbau projekts, welches verschiedenste Gewerke<br />
und Industriezweige<br />
mit- und nebeneinander tätig werden lässt,<br />
einen hohen Grad an Vernetzung mit verschiedenen<br />
Branchen.<br />
Der folgende Tag begann früh. Der Bus<br />
brachte die Teilnehmer vom Tagungshotel zum<br />
KIT Campus Nord. Nach einer Vorstellung des<br />
KIT, erfuhren wir, an welchen Stellen der<br />
Rückbau hinsichtlich eingesetzter Technik<br />
nicht nur Handwerk ist, sondern durchaus<br />
auch Aufgaben für die ingenieurtechnische<br />
Wissenschaft bereithält. Nach der Vorstellung<br />
der aktuellen und früheren Aufgaben des Instituts<br />
für Nukleare Entsorgung (INE), wo im<br />
Rahmen gesellschaftlicher Vorsorgeforschung<br />
grundlegende und anwendungsorientierte<br />
FuE-Arbeiten zur sicheren Ent sorgung radioaktiver<br />
Abfälle durchgeführt sowie Fragestellungen<br />
zum Rückbau kerntechnischer Anlagen<br />
thematisiert werden, starteten Besichtigungen.<br />
Im INE-Kontrollbereich wurden Details zu<br />
endlagerungsvorbereitenden Untersuchungen<br />
an Brenn elementen, zur Aktiniden forschung und über<br />
Möglichkeiten der Laserspek troskopie vorgestellt.<br />
An den INE-Beamlines der Synchrotron Radiation<br />
Facility „KARA“ erfuhren wir Details zu den Möglichkeiten<br />
und Anwendungsgebieten der Bildgebung mittels<br />
Röntgenstrahlung.<br />
Der Nachmittag gehörte ausführlichen Besichtigungen<br />
an den Anlagen der Kerntechnische Entsorgung Karlsruhe<br />
GmbH (KTE) am KIT Campus Nord – Zwischenlager, Wiederaufarbeitungsanlage<br />
(WAK) und Mehrzweckforschungsreaktor<br />
(MZFR).<br />
Das Zwischenlager beeindruckte durch seine Dimensionen.<br />
Interessant zu sehen, mit welchen Untersuchungsmethoden<br />
Reststoffe nach Eingang kontrolliert und<br />
qualifiziert werden. Die angewendeten Verfahren kommen<br />
auch bei der Nachqualifizierung älterer Reststoffe zum<br />
Einsatz. Parallel wird ein hoher Aufwand bei der Pflege der<br />
älteren Gebinde und der Konditionierung von Gebinden<br />
für das Endlager KONRAD betrieben.<br />
In der WAK erhielten wir Einblick in die Vorbereitungen<br />
des fernhantierten Rückbaus der Bereiche, die für einen<br />
manuellen Rückbau nicht zugänglich sind. Die Ortsdosisleistung<br />
ist insbesondere in der Verglasungsanlage so hoch, dass<br />
auch technische Geräte nach begrenzter Einsatzdauer beeinträchtigt<br />
werden bzw. versagen. Teils müssen hier zur<br />
Steuerung der Rückbauwerkzeuge Techniken und Verfahren<br />
etabliert werden, die in der Form bisher noch nirgends<br />
zum Einsatz kamen.<br />
Am MZFR konnten wir ein Kernkraftwerk in seinen<br />
„späten Jahren“ erleben. Die Führung brachte uns zu<br />
vielen interessanten Orten innerhalb dieses im Wesentlichen<br />
bis auf die Ge bäudestruktur entkernten Gebäudes.<br />
Neben letzten Rückbauarbeiten ist man dort mit dem<br />
messtech nischen Nachweis der Freigabefähigkeit, die zur<br />
Freigabe des Gebäudes gemäß § 29 StrlSchV führen soll,<br />
befasst. Interessant, wie anspruchsvoll auch oder gerade<br />
solche letzten Schritte sind, wo nicht mehr der Schutz der<br />
Person vor der Direktstrahlung, sondern der Nachweis der<br />
Kontaminations freiheit im Vordergrund steht.<br />
Der Tag wurde mit einem gemütlichen Beisammensein<br />
bei Speis und Trank abge rundet. Dabei waren Zeit und<br />
Gelegenheit, neue Kontakte zu knüpfen oder bestehende<br />
Kontakte zu vertiefen.<br />
Auch der letzte Tagungstag begann früh. Nach den<br />
intensiven Eindrücken des Vortags zu Rückbau und<br />
nuklearer Reststoffwirtschaft stand nun der wirtschaftliche<br />
und politische Rahmen des Rückbaus im Fokus.<br />
Zuerst wurde die Rolle der EU hinsichtlich wissenschaftlicher<br />
und politischer Unterstützung thematisiert.<br />
Zwei weitere Vorträge zeigten an praktischen<br />
Beispielen, was in Kernkraftwerken nach der Abschaltung<br />
passiert. Anhand der Kernkraftwerke Philippsburg und<br />
Neckarwestheim wurde gezeigt, wie das Management von<br />
Reststoffen vom Rückbau über den Transport bis hin zur<br />
Rezyklierung ineinandergreift – einfach gesagt: „Was<br />
passiert mit einem Kernkraftwerk nach der Abschaltung?“.<br />
Im Folgenden wurde berichtet, wie in den Blöcken A<br />
und B des Kernkraftwerks Biblis in Umsetzung erteilter<br />
Stilllegungs- und Rückbaugenehmigungen erste Abbaumaßnahmen<br />
durchgeführt werden. Geplant ist hier, auch<br />
im Unterschied zu den Anlagen in Philippsburg und<br />
Neckarwestheim, die Abbau- und Reststoffbearbeitungstätigkeiten<br />
innerhalb der bestehenden Gebäude durchzuführen.<br />
| | Tagungsteilnehmer auf Besichtigungstour am Institut für Technische Physik<br />
Im Anschluss wurde die Kostenschätzung von Stilllegungs-<br />
und Rückbaumaßnahmen thematisiert. Wichtig<br />
dabei ist, dass die Gesamtkosten mindestens zutreffend,<br />
jedoch keinesfalls zu niedrig geschätzt werden. Diese Verpflichtung<br />
ergibt sich nicht zuletzt aus den Bestimmungen<br />
zur Entsorgung von Kernkraftwerken bzw. -anlagen.<br />
Zugleich sind steuerrechtliche Vorgaben zu beachten, da<br />
Rückstellungen den steuerpflichtigen Gewinn mindern.<br />
Nicht zuletzt vor dem Hintergrund steigender Preise und<br />
teils unsicherer gesetzlicher Rahmenbedingungen haben<br />
die Betreiber ein vitales Interesse, dass die Gesamtkosten<br />
des Rückbaus ausreichend abgeschätzt werden.<br />
Den Abschluss des Vortragsteils am Vormittag bildeten<br />
Einblicke in die automatisierte Zerlegung von RDB-<br />
Einbauten mittels Unterwasser-Robotertechnik. Von der<br />
Ertüchtigung des Basisgeräts zur Unterwasserfähigkeit<br />
über die Erarbeitung eines Interventionskonzepts, der Entwicklung<br />
eines „Masterarms“ für die Werkzeugaufnahme,<br />
der Entwicklung eines Werkzeugwechselsystems bis zur<br />
Ausarbeitung von Schutzmechanismen ist dabei ein breites<br />
Spektrum von Herausforderungen zu bestehen, bevor der<br />
erste Einsatz stattfinden kann.<br />
KTG Inside
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
Gestärkt vom Mittagessen wurde die Tagung am<br />
Nachmittag mit der Besichtigung der Spultestanlage<br />
TOSKA des Instituts für Technische Physik (ITEP) am KIT,<br />
einer Anlage, in der große supraleitende Magnete für die<br />
Fusion getestet werden, sehr erfolgreich beendet.<br />
Dank an dieser Stelle allen Vortragenden und Organisatoren<br />
des KIT und KTE für die sehr guten Führungen und<br />
die perfekte Organisation des Besichtigungsnachmittags<br />
als auch allen weiteren Vortragenden aus der Industrie!<br />
Unser Dank gilt weiterhin allen Organisatoren, die<br />
erhebliche Teile ihrer Freizeit für das Zustandekommen<br />
und die Ausgestaltung der Tagung geopfert haben. Weiterhin<br />
danken wir unseren Arbeitgebern, Helfern sowie<br />
direkten und indirekten Sponsoren und Unterstützern.<br />
Ohne ihr Wirken hätte die Tagung nicht zu einem Erfolg<br />
werden können.<br />
Sven Jansen<br />
Im Namen des Vorstands der Jungen Generation der KTG<br />
MINT pink: WiN dabei<br />
Am 20.11.2017 fand im Körber-Forum in Hamburg der<br />
Programmabschluss von „MINT pink“ statt. MINT pink ist<br />
ein schulübergreifendes Programm, das ausgewählte<br />
Schülerinnen der Mittelstufe für die Wahl eines naturwissenschaftlichen<br />
Profils in der Oberstufe ermutigt<br />
und Studien-, Arbeits- und Karrieremöglichkeiten<br />
im Mathe matik- Informatik-Naturwissenschaft-Technik-<br />
Bereich auf zeigt.<br />
| | MINT pink: WiN dabei. Chantal Greul stellt ihren Beruf in der Kerntechnik<br />
Schülerinnen vor.<br />
Chantal Greul durfte als Role Model über 90 Mädchen<br />
den Beruf der Ingenieurin in der Kerntechnik vorstellen.<br />
Nach einer kurzen Vorstellung des eigenen Lebenslaufes<br />
und des Arbeitsalltages in einer kerntechnischen Anlage,<br />
durften die Schülerinnen in kleinen Gesprächsrunden<br />
ihre Fragen stellen. Diese reichten von allgemeinen Fragen<br />
bis hin zu spezifischen Fachfragen rund um Kernenergie,<br />
Rückbau und Endlagerung in Deutschland. Die Veranstaltung<br />
war eine interessante Gelegenheit mit potenziellem<br />
Nachwuchs in Kontakt zu kommen und sie über<br />
die spannende Arbeit in der Kernenergiebranche zu<br />
informieren. Auch die Programmauswertung zeigt den<br />
Erfolg des MINT-pink-Programmes. Vor Programmstart<br />
konnten sich 27 % der Mädchen vorstellen, das Physikoder<br />
Chemieprofil in der Oberstufe zu wählen. Nach<br />
Programmende waren es 45 %.<br />
KTG Inside<br />
Verantwortlich<br />
für den Inhalt:<br />
Die Autoren.<br />
Lektorat:<br />
Sibille Wingens,<br />
Kerntechnische<br />
Gesellschaft e. V.<br />
(KTG)<br />
Robert-Koch-Platz 4<br />
10115 Berlin<br />
T: +49 30 498555-50<br />
F: +49 30 498555-51<br />
E-Mail: s.wingens@<br />
ktg.org<br />
127<br />
KTG INSIDE<br />
Yvonne Broy<br />
www.ktg.org<br />
Advertisement<br />
KTG Inside
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
128<br />
KTG INSIDE<br />
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Februar <strong>2018</strong><br />
90 Jahre wird<br />
10. Dipl.-Ing. Hans-Peter Schabert,<br />
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89 Jahre wird<br />
20. Dr. Helmut Hübel, Bensberg<br />
88 Jahre wird<br />
5. Dr. Eberhard Teuchert, Leverkusen<br />
87 Jahre wird<br />
14. Dipl.-Ing. Heinrich Kahlow, Rheinsberg<br />
85 Jahre wird<br />
11. Dr. Rudolf Büchner, Dresden<br />
84 Jahre werden<br />
9. Dr. Horst Keese, Rodenbach<br />
12. Dipl.-Ing-. Horst Krause, Radebeul<br />
23. Prof. Dr. Dr.-Ing. E.h. Adolf Birkhofer,<br />
Grünwald<br />
82 Jahre werden<br />
6. Dr. Ashu-T. Bhattacharyya, Erkelenz<br />
17. Dr. Helfrid Lahr, Wedemark<br />
81 Jahre werden<br />
5. Prof. Dr. Arnulf Hübner, Berlin<br />
6. Dipl.-Ing. Heinrich Moers,<br />
Maitland/USA<br />
11. Dr. Günter Keil, Sankt Augustin<br />
18. Dipl.-Ing. Hans Wölfel, Heidelberg<br />
21. Dipl.-Ing. Hubert Andrae, Rösrath<br />
80 Jahre wird<br />
15. Dr. Hans-Heinrich Krug, Saarbrücken<br />
79 Jahre werden<br />
3. Dr. Roland Bieselt, Kürten<br />
8. Dr. Joachim Madel, St. Ingbert<br />
8. Dr. Herbert Spierling, Dietzenbach<br />
22. Dr. Manfred Schwarz, Dresden<br />
78 Jahre werden<br />
9. Dr. Gerhard Preusche, Herzogenaurach<br />
13. Dr. Hans-Ulrich Fabian, Gehrden<br />
14. Dipl.-Ing. Kurt Ebbinghaus,<br />
Bergisch Gladbach<br />
21. Dr. Jürgen Langeheine, Gauting<br />
23. Dr. Gerhard Heusener, Bruchsal<br />
25. Prof. Dr. Sigmar Wittig, Karlsruhe<br />
77 Jahre wird<br />
16. Dr. Jürgen Lockau, Erlangen<br />
76 Jahre werden<br />
6. Dr. Michael Schneeberger, Linz/A<br />
22. Cornelis Broeders, Linkenheim<br />
Die KTG gratuliert ihren Mitgliedern sehr herzlich zum<br />
Geburtstag und wünscht ihnen weiterhin alles Gute!<br />
75 Jahre werden<br />
5. Dr. Joachim Banck, Heusenstamm<br />
9. Dr. Friedrich-Karl Boese, Leonberg<br />
13. Dr. Ingo-Armin Brestrich, Plankstadt<br />
20. Ing. Leonhard Irion, Rückersdorf<br />
28. Dr. Klaus Tägder, Sankt Augustin<br />
70 Jahre werden<br />
7. Dr. Hans-Hermann Remagen, Brühl<br />
8. Dr. Max Hillerbrand, Erlangen<br />
14. Reinhold Rothenbücher, Erlangen<br />
23. Dr. Rudolf Görtz, Salzgitter<br />
29. Dr. Anton von Gunten, Oberdiessbach<br />
65 Jahre werden<br />
3. Dr. Reinhard Knappik, Dresen<br />
20. Dipl.-Ing. Berthold Racky, Nidderau<br />
60 Jahre werden<br />
3. Prof. Dr. Sabine Prys, Offenburg<br />
3. Dipl.-Ing. Siegfried Wegerer,<br />
Tiefenbach<br />
10. Dipl.-Ing. (FH) Anton Hums,<br />
Essenbach<br />
50 Jahre werden<br />
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20. Dr. Josef Engering, Jülich<br />
22. Toralf Wolf, Plauen<br />
28. Dipl.-Ing. Jörg Schneider, Radebeul<br />
März <strong>2018</strong><br />
91 Jahre wird<br />
27. Prof. Dr. Bernhard Liebmann,<br />
Kronberg<br />
88 Jahre werden<br />
6. Prof. Dr. Hubertus Nickel, Jülich<br />
25. Dr. Hans-Ulrich Borgstedt, Karlsruhe<br />
25. Dr. Peter Borsch, Dresden<br />
87 Jahre wird<br />
17. Dipl.-Ing. Hans Waldmann<br />
86 Jahre wird<br />
14. Dr. Peter Engelmann,<br />
Eggenstein-Leopoldshafen<br />
85 Jahre werden<br />
26. Dipl.-Ing. Gerhard Frei, Uttenreuth<br />
30. Dipl.-Phys. Dieter Pleuger, Kiedrich<br />
84 Jahre werden<br />
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18. Dipl.-Ing. Willi Riebold, München<br />
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82 Jahre werden<br />
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8. Prof. Dr. Erich Tenckhoff, Erlangen<br />
19. Dr. Hermann Hinsch, Hannover<br />
81 Jahre wird<br />
29. Dipl.-Ing. Friedrich Garzarolli, Fürth<br />
80 Jahre werden<br />
4. Dr. Rainer Göhring, Nauen<br />
6. Dipl.-Math. Udo Harten, Stutensee<br />
10. Dr. Hein-Jürzen Kriks, Braunschweig<br />
11. Peter Vagt, Rösrath<br />
14. Dr. Peter Paetz, Bergisch Gladbach<br />
16. Prof. Dr. Helmut Röthmeyer,<br />
Braunschweig<br />
22. Dr. Bruno-J. Baumgartl, Weiterstadt<br />
79 Jahre werden<br />
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1. Dipl.-Ing. Wolfgang Dietz, Lindlar<br />
7. Dr. Kurt Vinzens, Berg-Aufkirchen<br />
17. Dipl.-Phys. Renate von Le Suire,<br />
Seeshaupt<br />
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Wonga Park/AUS<br />
25. Dipl.-Ing. Joachim Koch, Mömbris<br />
78 Jahre werden<br />
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3. Dr. Lutz Niemann, Holzkirchen<br />
3. Dipl.-Ing. Eberhard Schomer, Erlangen<br />
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12. Prof. Dr. Arndt Falk, Sterup<br />
18. Dipl.-Ing. Friedhelm Hülsmann,<br />
Garbsen<br />
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29. Ing. Dieter-W. Sauer, Berlin<br />
29. Dipl.-Phys. Harald Reinhardt,<br />
Leverkusen<br />
77 Jahre werden<br />
4. Ing. Ulrich Ristow, Neu-Isenburg<br />
8. Dr. Frank Steinbrunn, Fröndenberg<br />
14. Dipl.-Ing. Bernd Jürgens, Hirschberg<br />
22. Dipl.-Phys. Gerhard Jourdan, Landau<br />
76 Jahre wird<br />
10. Dipl.-Phys. Alfons Scholz, Brühl<br />
75 Jahre werden<br />
7. Dr. Peter Royl, Stutensee<br />
16. Dipl.-Ing. Jochen Heinecke, Kürten<br />
20. Dipl.-Ing. Jörg Brauns, Hanau<br />
26. Dr. Jürgen P. Lempert, Hannover<br />
26. Graeme William Catto, Buch a. Erlbach<br />
70 Jahre werden<br />
5. Dipl.-Wirtsch.-Ing. Bernd Pontani,<br />
Alzenau<br />
13. Dipl.-Kfm. Jochen Bläsing, Mörlenbach<br />
22. Dr. Volker Mirschinka, Essen<br />
65 Jahre wird<br />
21. Dr. Ulrich Rohde, Dresden<br />
60 Jahre wird<br />
26. Dr. Sheikh Shahee, Leinburg<br />
50 Jahre werden<br />
20. Thomas Wiese, Ebermannstadt<br />
30. Dipl.-Ing. Heiko Ringel, Offingen<br />
KTG Inside
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
Top<br />
IAEA: Solving the back end:<br />
Finland’s key to the final<br />
disposal of spent nuclear fuel<br />
(iaea) Countries operating nuclear<br />
power plants store their spent nuclear<br />
fuel either at reactor sites or away<br />
from them. Spent fuel can be dangerous<br />
to people and the environment<br />
if not properly managed; therefore,<br />
a publicly acceptable, permanent<br />
solution for its disposal is needed.<br />
While a number of countries are<br />
considering deep geological disposal<br />
repositories, Finland is the only<br />
country that has begun the construction<br />
of a repository for the final<br />
disposal of its spent nuclear fuel.<br />
At a depth of 400 to 450 metres<br />
and with about 70 km of tunnels and<br />
shafts, the ONKALO repository in<br />
Olkiluoto on Finland’s west coast<br />
will house copper canisters filled<br />
with spent fuel from nuclear power<br />
reactors. It is expected to receive<br />
waste for about 100 years, after which<br />
time it will be sealed.<br />
“Since the decision was made<br />
40 years ago on the overall waste<br />
management strategy and on a deep<br />
geological repository as the primary<br />
option for spent nuclear fuel, all the<br />
stakeholders have stood by it,” said<br />
Tiina Jalonen, Senior Vice President<br />
for Development at Posiva, the company<br />
in charge of the project. “Governments<br />
and people have changed,<br />
but the decision and the vision for the<br />
future have remained the same.”<br />
Another reason why Finland’s<br />
model has worked is the timely<br />
involvement of all the stakeholders in<br />
the project, who worked as one team,<br />
targeting the same goal.<br />
“The roles between the different<br />
stakeholders have been clear. The<br />
decision makers have developed<br />
legislation in parallel to introducing<br />
nuclear energy, and the Radiation and<br />
Nuclear Safety Authority of Finland<br />
(STUK) has developed safety guides,<br />
regulations and competences to<br />
review and inspect our documentation<br />
and applications,” said Jalonen.<br />
Moreover, involving STUK from the<br />
beginning was crucial to building the<br />
trust in the project. “It wouldn’t have<br />
worked if any of the stakeholders were<br />
missing from the process,” explained<br />
Petteri Tiippana, Director General at<br />
STUK. “Active participation of the safety<br />
regulator provided the local community<br />
with additional assurances.”<br />
In fact, public acceptance was<br />
crucial for the success of the project.<br />
The selection of the Olkiluoto site<br />
–home to three nuclear reactors – as<br />
the repository site was made, not only<br />
for the geological suitability of this<br />
area, but also for the acceptance of the<br />
people living there. Finland conducted<br />
many studies about local and<br />
national attitudes toward the project,<br />
which showed that people living<br />
around nuclear power plants tend to<br />
have more trust in nuclear projects.<br />
“Trust has been one cornerstone<br />
in being able to proceed according to<br />
the Government’s schedule,” Jalonen<br />
said. “Building trust has required<br />
extensive and open communication<br />
with local people, the authority and<br />
the decision makers.”<br />
The project is based on the “multiple<br />
barriers” concept, which aims to<br />
provide needed containment and<br />
isolation to prevent spent fuel from<br />
leaking and spreading, according to<br />
Posiva. The combination of bedrock,<br />
disposal canisters surrounded by clay,<br />
tunnels filled with clay containing<br />
backfilling materials and plugging the<br />
tunnel’s mouth will all serve as protective<br />
multiple barriers.<br />
Who’s next?<br />
Two other countries have made progress<br />
towards building repositories for<br />
high-level radioactive waste or spent<br />
fuel declared as waste. In June 2016,<br />
the Swedish Radiation Safety Authority<br />
endorsed the licence application<br />
for the future spent fuel deep geological<br />
repository at Forsmark. Review by<br />
the Swedish Land and Environment<br />
Court for environmental licencing of<br />
the project started in September 2017.<br />
In France, the licence application<br />
for the deep geological disposal<br />
facility, Cigéo, is under preparation; it<br />
is planned to be submitted by the end<br />
of <strong>2018</strong>, with construction starting in<br />
2<strong>02</strong>0. The pilot phase of disposal<br />
could start as soon as 2<strong>02</strong>5. It will<br />
contain waste from the reprocessing<br />
of spent fuel from France’s current<br />
fleet of nuclear power plants and<br />
other long-lived radioactive waste.<br />
The science<br />
High-Level Radioactive Waste (HLW)<br />
is produced from the burning of<br />
uranium fuel in nuclear power reactors.<br />
It is of two kinds: spent fuel,<br />
declared as waste and ready for<br />
disposal, or waste resulting from the<br />
reprocessing of spent fuel.<br />
Due to its high radioactivity and<br />
very long half-life (the time it takes<br />
for a radioactive substance to lose half<br />
its radioactivity), HLW has to be well<br />
contained and isolated from the human<br />
environment. Intensive research<br />
has identified the suitability of various<br />
rock types to host deep geological repositories<br />
and engineered barrier systems<br />
to isolate the waste. These repositories<br />
are constructed in suitable geological<br />
formations at a depth of several<br />
hundred meters and designed to<br />
contain high-level waste for hundreds<br />
of thousands of years.<br />
| | www.iaea.org<br />
Reactors<br />
Georgia’s commitment to<br />
new nuclear a win for US<br />
economy, environment<br />
(nei) In response to the announcement<br />
that the Georgia Public Service Commission<br />
unanimously approved an<br />
order allowing continued construction<br />
of two additional reactors at Plant<br />
Vogtle, the following is a statement by<br />
NEI President and CEO Maria Korsnick.<br />
“Completing the Plant Vogtle expansion<br />
is good for America on many<br />
levels, especially in terms of our<br />
national security, our commitment to a<br />
cleaner environment, and energy<br />
diversity. In addition to the thousands<br />
of workers who will cheer this decision,<br />
these nuclear facilities when<br />
completed will produce decades worth<br />
of clean, reliable power and provide<br />
billions of dollars in economic benefits.<br />
“Demonstrating we can build and<br />
complete new nuclear plants here in<br />
America will help us regain our<br />
leader ship in a technology we invented.<br />
America’s pre-eminence in<br />
nuclear energy makes our country<br />
safer because it allows us to influence<br />
and control how this technology is<br />
used around the world.”<br />
| | www.nei.com<br />
Finnish cities to explore Small<br />
Modular Reactors for district<br />
heating<br />
(nucnet) The Finnish cities of Helsinki,<br />
Espoo and Kirkkonummi have begun<br />
studies to find out if it would be<br />
feasible to replace coal and natural<br />
gas in district heating with small<br />
modular nuclear reactors (SMRs), the<br />
environmental group Ecomodernist<br />
Society of Finland said. The society<br />
said a feasibility study will be carried<br />
out into the potential for SMRs to<br />
replace fossil fuel-burning in cities<br />
around the Helsinki metropolitan<br />
area. Several advanced SMRs are in<br />
development and coming to market by<br />
2030 that could meet the specifications,<br />
the society said. Most of the<br />
district heating in Finland is produced<br />
129<br />
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130<br />
NEWS<br />
*)<br />
Net-based values<br />
(Czech and Swiss<br />
nuclear power<br />
plants gross-based)<br />
1)<br />
Refueling<br />
2)<br />
Inspection<br />
3)<br />
Repair<br />
4)<br />
Stretch-out-operation<br />
5)<br />
Stretch-in-operation<br />
6)<br />
Hereof traction supply<br />
7)<br />
Incl. steam supply<br />
8)<br />
New nominal<br />
capacity since<br />
January 2016<br />
9)<br />
Data for the Leibstadt<br />
(CH) NPP will<br />
be published in a<br />
further issue of <strong>atw</strong><br />
BWR: Boiling<br />
Water Reactor<br />
PWR: Pressurised<br />
Water Reactor<br />
Source: VGB<br />
by burning coal, natural gas, wood<br />
fuels and peat. While many Finnish<br />
cities have progressive climate policies<br />
and goals, they have struggled to<br />
decarbonise heating and liquid fuels,<br />
the society said. Rauli Partanen,<br />
vice-chair of the society and an independent<br />
energy analyst and author,<br />
said there are “significant economic<br />
possibilities” in producing combined<br />
heat and power (CHP) with nuclear<br />
reactors. He said: “With CHP, the<br />
reactor could produce roughly twice<br />
the value per installed capacity compared<br />
with just electricity production,<br />
while at the same time decarbonising<br />
heat production.” He said nuclear<br />
is great for baseload needs, but<br />
with advanced technologies such as<br />
high temperature reactors and high<br />
temperature electrolysis, nuclear can<br />
also be used to decarbonise not just<br />
electricity, heat but also transportation<br />
fuels and many industries”.<br />
| | www.vtt.fi<br />
EDF ‘Cannot build new<br />
reactors in France without<br />
guarantees’<br />
(nucnet) French state-controlled<br />
utility EDF can no longer build new<br />
nuclear reactors in France without<br />
state support, chief executive officer<br />
Jean-Bernard Levy was quoted as<br />
saying in an interview with the Ouest<br />
France daily newspaper. Asked when<br />
EDF could build new reactors at home,<br />
Mr Levy said: “Henceforth, we cannot<br />
build new reactors without adequate<br />
regulation providing guaranteed<br />
income”. He said the Flamanville-3<br />
EPR project under construction in<br />
northern France began at a time of<br />
high power prices and that now all<br />
power sources, nuclear as well as<br />
renewables, need to get “the same<br />
visibility on sales prices”. For its<br />
project to build two EPRs at Hinkley<br />
Point in the UK, EDF obtained an<br />
EU-approved state-guaranteed price<br />
of £92.5 per MWh over 35 years,<br />
which is above current market prices.<br />
The government of French president<br />
Emmanuel Macron is planning to close<br />
old reactors to reduce the share of nuclear<br />
energy in French power generation<br />
to 50% by around 2035 from 75 %<br />
today. Mr Levy said EDF expects to get<br />
approval to load nuclear fuel at<br />
Flamanville-3 at the end of <strong>2018</strong>.<br />
| | www.edf.com<br />
Japan’s Regulator:<br />
Kashiwazaki Kariwa-6 and -7<br />
meet new safety standards<br />
(nucnet) Units 6 and 7 of the<br />
Kashiwazaki Kariwa nuclear power<br />
station in Niigata Prefecture, northwestern<br />
Japan, meet new regulatory<br />
standards imposed after the March<br />
2011 Fukushima-Daiichi accident, the<br />
Nuclear Regulation Authority said.<br />
The two units, owned and operated<br />
by Tokyo Electric Power Company<br />
(Tepco) are the first boiling water<br />
reactors to meet the new standards.<br />
Tepco also owns the Fukushima-<br />
Daiichi station.<br />
Kashiwazaki Kariwa was not affected<br />
by the March 2011 earthquake and<br />
tsunami which damaged Fukushima-<br />
Daiichi, although the station’s seven<br />
reactors had all been offline for up to<br />
three years following a 2007 earthquake<br />
which damaged the site but did<br />
not damage the reactors themselves.<br />
While the units were offline, work<br />
was carried out to improve the<br />
facility’s earthquake resistance.<br />
Accord ing to JAIF, the governor of<br />
Niigata Prefecture, Ryuichi Yoneyama,<br />
has said he will not discuss restarting<br />
the two units until further information<br />
about nuclear incidents and their<br />
impact on public health is made available.<br />
Both units are 1,315-MW BWRS.<br />
Kashiwazaki Kariwa-6 began commercial<br />
operation in November 1996 and<br />
Kashiwazaki Kariwa-7 in July 1997.<br />
Tokyo-based nuclear industry<br />
group the Japan Atomic Industrial<br />
Forum said 14 nuclear units have now<br />
been approved by the NRA as meeting<br />
the new standards. They are<br />
Kashiwazaki Kariwa-6 and -7,<br />
Operating Results October 2017 (corrigendum, <strong>atw</strong> 1 (<strong>2018</strong>) p. 58)<br />
Plant name<br />
Type<br />
Nominal<br />
capacity<br />
gross<br />
[MW]<br />
net<br />
[MW]<br />
Operating<br />
time<br />
generator<br />
[h]<br />
Energy generated, gross<br />
[MWh]<br />
Time availability<br />
[%]<br />
Energy availability<br />
[%] *) Energy utilisation<br />
[%] *)<br />
Month Year Since Month Year Month Year Month Year<br />
commissioning<br />
KBR Brokdorf DWR 1480 1410 745 937 223 3 903 011 338 316 924 100.00 41.98 93.94 39.11 84.59 35.98<br />
KKE Emsland 4) DWR 1406 1335 745 1 004 762 9 304 398 333 303 977 100.00 91.93 99.93 91.77 95.81 90.70<br />
KWG Grohnde DWR 1430 1360 745 970 799 8 126 396 365 069 095 100.00 87.01 94.85 83.35 90.42 77.21<br />
KRB B Gundremmingen 4) SWR 1344 1284 745 778 570 8 351 414 330 004 358 100.00 91.83 100.00 90.98 76.78 84.52<br />
KRB C Gundremmingen SWR 1344 1288 745 968 428 7 990 831 318 640 904 100.00 85.41 99.83 83.30 96.32 81.<strong>02</strong><br />
KKI-2 Isar DWR 1485 1410 745 1 073 129 9 378 353 339 453 163 100.00 89.84 99.71 89.37 96.66 86.22<br />
KKP-2 Philippsburg DWR 1468 14<strong>02</strong> 745 1 046 248 5 745 846 353 059 535 100.00 55.80 99.92 55.72 94.15 52.80<br />
GKN-II Neckarwestheim DWR 1400 1310 745 1 011 300 8 549 400 318 131 734 100.00 86.71 99.50 86.46 97.13 83.84<br />
Operating Results November 2017<br />
Plant name<br />
Type<br />
Nominal<br />
capacity<br />
gross<br />
[MW]<br />
net<br />
[MW]<br />
Operating<br />
time<br />
generator<br />
[h]<br />
Energy generated, gross<br />
[MWh]<br />
Time availability<br />
[%]<br />
Energy availability Energy utilisation<br />
[%] *) [%] *)<br />
Month Year Since Month Year Month Year Month Year<br />
commissioning<br />
KBR Brokdorf DWR 1480 1410 720 942 685 4 845 695 339 259 608 100.00 47.20 93.97 44.04 88.16 40.67<br />
KKE Emsland 4) DWR 1406 1335 720 1 017 448 10 321 846 334 321 425 100.00 92.65 99.77 92.49 100.61 91.59<br />
KWG Grohnde DWR 1430 1360 446 586 675 8 713 070 365 655 769 61.99 84.77 56.84 80.97 56.57 75.35<br />
KRB B Gundremmingen 4) SWR 1344 1284 720 701 347 9 052 761 330 705 705 100.00 92.56 98.85 91.69 71.32 83.33<br />
KRB C Gundremmingen SWR 1344 1288 720 956 516 8 947 347 319 597 420 100.00 86.72 98.05 84.62 98.30 82.57<br />
KKI-2 Isar DWR 1485 1410 720 1 061 544 10 439 897 340 514 707 100.00 90.75 100.00 90.33 99.05 87.37<br />
KKP-2 Philippsburg DWR 1468 14<strong>02</strong> 720 1 042 562 6 788 408 354 1<strong>02</strong> 097 100.00 59.77 100.00 59.69 97.08 56.77<br />
GKN-II Neckarwestheim DWR 1400 1310 720 996 000 9 545 400 319 127 734 100.00 87.91 98.51 87.54 99.08 85.21<br />
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<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
Mihama 3, Takahama-1, -2, -3 and -4,<br />
and Ohi-3 and -4, Ikata-3, Genkai-3<br />
and -4 and Sendai-1 and -2.<br />
All of Japan’s 48 reactors were shut<br />
between 2011 and 2012 after the<br />
Fukushima-Daiichi accident. Five<br />
units have resumed commercial operation.<br />
They are: Takahama-3 and -4,<br />
Ikata-3 and Sendai-1 and -2.<br />
Before the Fukushima-Daiichi<br />
accident Japan had generated around<br />
30% of its electricity with plans to<br />
increase the share to 40%. According<br />
to the International Atomic Energy<br />
Agency Japan’s nuclear share in 2016<br />
was 2.15%.<br />
| | www.tepco.co.jp, www.nsr.go.jp<br />
Slovakia: Mochovce-3 startup<br />
target of end <strong>2018</strong> is realistic<br />
(se) The schedule for the completion<br />
of the third and fourth units of the<br />
Mochovce nuclear power station in<br />
Slovakia is realistic, with Unit 3 likely<br />
to begin commercial operation at the<br />
end of <strong>2018</strong> and Unit 4 at the end of<br />
2019, regulator UJD said. According<br />
to utility Slovenské Elektrárne, fuel<br />
will be loaded into Unit 3 in July <strong>2018</strong>.<br />
Preparations have begun for the start<br />
of a cold pressure test of the primary<br />
circuit at Unit 3, local media reports<br />
said. In June 2016 the utility said construction<br />
work at Unit 3 was “more<br />
than 92%” finished, with Unit 4 at<br />
75%. Mochovce-3 and -4 are both<br />
440-MW pressurised water reactors of<br />
the Russian VVER V-213 design.<br />
| | www.seas.sk<br />
Plans for UK new nuclear<br />
move forward as regulator<br />
approves design for UK-ABWR<br />
(nucnet) Plans for two new nuclear<br />
power stations in the UK have taken a<br />
crucial step forward as UK regulators<br />
approved the design of the reactor<br />
technology for the projects. The Office<br />
for Nuclear Regulation gave the green<br />
light today for the UK Advanced<br />
Boiling Water Reactor (UK-ABWR),<br />
designed by Hitachi-GE. The ONR<br />
said the design is suitable for construction<br />
in the UK, marking the end<br />
of a five-year regulatory process.<br />
Horizon Nuclear Power is proposing<br />
to build and operate two of these<br />
reactors in Wylfa Newydd on Anglesey<br />
and Oldbury-on-Severn in Gloucestershire.<br />
Duncan Hawthorne, Horizon’s<br />
chief executive, said: “This is a huge<br />
milestone for Horizon and a major<br />
leap forward for us in bringing<br />
much-needed new nuclear power to<br />
the UK.” Horizon said today that<br />
“steady progress” is being made with<br />
the Hitachi-backed Wylfa Newydd<br />
project, including the submission of<br />
the site licence application and completion<br />
of a third public consultation.<br />
Attention will now turn to financing<br />
the Wylfa Newydd project. Earlier this<br />
year Horizon said: “We have always<br />
been clear that we are looking to bring<br />
other investors into Horizon. Based on<br />
the strengths of our project, we are in<br />
positive discussions with a number of<br />
parties but we will not be commenting<br />
on the process whilst it is ongoing.”<br />
| | www.onr.ork.uk,<br />
www.hitachi-hgne-uk-abwr.co.uk<br />
Company News<br />
Framatome pursues the<br />
industrial and technological<br />
adventure of the nuclear<br />
energy business<br />
(framatome) New NP, a subsidiary of<br />
AREVA NP, becomes Framatome, a<br />
company whose capital is owned by<br />
the EDF group (75.5%), Mitsubishi<br />
Heavy Industries (MHI – 19.5%) and<br />
Assystem (5 %).<br />
Framatome confirms its recognized<br />
manufacturer’s ambition: being the<br />
sup plier of safe and competitive nuclear<br />
solutions, supporting its electrical<br />
utility customers all over the world.<br />
Framatome, 14,000 employees<br />
worldwide<br />
Framatome employees have recognized<br />
skills, a know-how that was<br />
forged over the long history of the<br />
company and that has enabled us to<br />
build outstanding industrial success in<br />
France and internationally. Framatome<br />
places its faith in the expertise<br />
of the women and the men who are at<br />
its very core: this expertise underpins<br />
the company’s strategy and is key to<br />
serving the needs of its customers and<br />
furthering the success of the nuclear<br />
industry.<br />
In the words of Bernard Fontana,<br />
Chairman of the Managing Board and<br />
Chief Executive Officer of Framatome,<br />
“Framatome possesses unique knowhow<br />
in an industry that today is and<br />
will remain key for a low-carbon<br />
energy mix. Our employees in France<br />
and around the world have been able<br />
to face considerable challenges in<br />
recent years. As we emerge from this<br />
transition phase, I share their pride<br />
and I want to thank them for all<br />
the work they have accomplished.<br />
Steeped in a rich heritage, Framatome<br />
is today one of the reference players in<br />
the nuclear sector worldwide, benefiting<br />
from unparalleled operating<br />
feedback. Our ambition is delivering a<br />
level of industrial excellence that is<br />
recognized by our customers.”<br />
Proud of its core business expertise<br />
as designer, supplier and installer of<br />
nuclear steam supply systems Framatome<br />
contributes to the design of<br />
power plants, supplies the nuclear<br />
steam supply system, designs and<br />
manufactures components and fuels,<br />
integrates the instrumentation and<br />
control systems and carries out the<br />
maintenance of in-service nuclear<br />
reactors. It delivers its high-performance<br />
products and services to<br />
customers all over the world.<br />
Framatome is a technology company,<br />
holding around 3,500 patents<br />
covering some 680 inventions, which<br />
serve the most demanding needs of its<br />
customers who number among the<br />
key international energy leaders.<br />
Framatome operates on more than<br />
250 reactors worldwide.<br />
An internationally-focused strategy<br />
of development and industrial excellence<br />
Framatome has the determination<br />
to go further in terms of industrial<br />
excellence, leveraging five strategic<br />
axes: proven and sustainable expertise,<br />
performance in delivering, an<br />
agile and adaptive organization, safe<br />
and competitive solutions and international<br />
development. With an existing<br />
global fleet of some 440 reactors<br />
representing output of around<br />
390 GWe in 31 countries, and with<br />
new nuclear capacity on its way, the<br />
nuclear market presents opportunities<br />
in the areas of components, fuel, retrofits<br />
and services. (18191512)<br />
| | www.framatome.com<br />
Brookfield to acquire Westinghouse<br />
Electric Company<br />
(westn) Westinghouse Electric Company,<br />
the global leader in nuclear<br />
technology, fuel and services, has<br />
agreed to be acquired by Brookfield<br />
Business Partners L.P. (NYSE:BBU)<br />
(TSX:BBU.UN) together with institutional<br />
partners (collectively, “Brookfield”)<br />
for approximately $ 4.6 billion.<br />
The purchase price for substan tially<br />
all of the global business of Westinghouse<br />
Electric Company LLC and its<br />
affiliated debtors and debtors- in-posses<br />
sion (collectively “Westinghouse”)<br />
excludes cash, but includes the assumption<br />
of certain pension, environmental<br />
and other operating obligations.<br />
“Brookfield’s acquisition of Westinghouse<br />
reaffirms our position as the<br />
leader of the global nuclear industry,”<br />
said Westinghouse President & CEO<br />
José Emeterio Gutiérrez. “Our transformation<br />
and strategic restructuring<br />
131<br />
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<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
132<br />
NEWS<br />
process is creating a stronger, stable,<br />
and more streamlined global Westinghouse<br />
business, for the benefit of our<br />
customers and employees.”<br />
Brookfield’s acquisition of Westinghouse<br />
is expected to close in the third<br />
quarter of <strong>2018</strong>, subject to Bankruptcy<br />
Court approval and customary closing<br />
conditions including, among others,<br />
regulatory approvals. Throughout the<br />
process, Westinghouse will continue<br />
to operate in the ordinary course of<br />
business under its existing senior<br />
management.<br />
PJT Partners is the financial advisor<br />
to Westinghouse, Weil, Gotshal &<br />
Manges LLP is Westinghouse’s legal<br />
counsel, and AlixPartners LLP is Westinghouse’s<br />
turnaround consultant.<br />
| | www.westinghousenuclear.com,<br />
www.brookfield.com<br />
People<br />
Appointment of the<br />
Framatome Managing Board<br />
(framatome) The Supervisory Board<br />
of Framatome, meeting under the<br />
chairmanship of Jean-Bernard Lévy,<br />
Chairman and CEO of EDF, appointed<br />
Some Questions and Answers About Energy.<br />
Answers<br />
1b. False: All leading scenarios predict a rise of the global<br />
energy demand for the next decades (2015 to 2040:<br />
between 10 % to 40 %) mainly driven by the increase<br />
of the population and the growing demand in developing<br />
countries.<br />
2b. False: All leading scenarios predict an over proportional rise<br />
of the global electricity demand for the next decades (2015<br />
to 2040: between 60 % to 80 %) mainly driven by the<br />
increase of the population, the growing demand in<br />
developing countries and the today’s poor access to<br />
electricity for about one third of the world’s population.<br />
3b. False: In 2017 the global coal production increased by 2 %<br />
compared with the previous year 2016.<br />
4c. Since 2010 about 11 % of world’s electricity demand is<br />
produced in nuclear power plants.<br />
5b. About 5 % of world’s electricity demand was produced by<br />
wind (4 %) and solar (1 %) in 2017.<br />
6c. United States, with about 6,800 billions of tonnes,<br />
98 % thereof coal; EU about 530 billions of tonnes,<br />
95 % thereof coal<br />
7d. China. The carbon dioxide emission are always twice<br />
the emissions of the USA and three times the emissions<br />
of all 28 EU countries.<br />
8d. Hydropower, 4 to 13 g CO 2 per kWh.<br />
Wind and nuclear: about 8 to 20 g CO 2 per kWh.<br />
Photovoltaics: 35 to 160 g CO 2 per kWh.<br />
9a. Nuclear power, especially small modular reactors<br />
with advanced fuel usage.<br />
10d. Nuclear power. The number of lost lifetime-days per<br />
kilowatt-hour produced from nuclear power is in the range<br />
of wind power and about 5- to 100-times lower than of<br />
every other primary energy source.<br />
11d. The natural radiation caused by Thorium and its decay<br />
products in Guarapari (Monazit area) is up to<br />
10,000-times higher than the radiation from nuclear<br />
reactors in normal operation.<br />
12b. False: There are 448 nuclear power plants in operation<br />
worldwide and 59 under construction. About 120 additional<br />
power plants are planned. Only some plants will be shutdown<br />
in the upcoming year, mainly in the „old“ countries.<br />
Further expansion programmes are under the way e.g. in<br />
China with more than 100 plants to be in operation in the<br />
period 2030 to 2040 and the „Newcomer“ countries in Asia.<br />
Bernard Fontana Chairman of the<br />
Managing Board and Chief Executive<br />
Officer.<br />
It also appointed Philippe Braidy<br />
Managing Director, member of the<br />
Managing Board.<br />
Bernard Fontana holds a degree in<br />
engineering from the École Polytechnique<br />
and the École Nationale<br />
Supérieure des Techniques Avancées<br />
in Paris. He has 30 years’ experience<br />
in the chemical, steel and building<br />
materials industries (SNPE, Arcelor-<br />
Mittal, APERAM and Holcim).<br />
From February 2012 to September<br />
2015, he served as CEO of Holcim Ltd.<br />
Since September 1, 2015, Bernard<br />
Fontana had been Chief Executive<br />
Officer of AREVA NP.<br />
Philippe Braidy, former Head of<br />
regional and local Development and<br />
network in French Caisse des Dépôts,<br />
has 30 years’ experience as Technical<br />
and Financial Director in public<br />
administrations (French Ministry<br />
of Budget, Prime minister’s office,<br />
CEA…). Up to now he has been<br />
managing the Finance, Strategy/Innovation/Communications,<br />
Legal/Compliance,<br />
Risks/Audit, and Information<br />
Systems Functions of AREVA NP.<br />
| | www.framatome.com<br />
Einige Fragen und Antworten zum Thema Energie.<br />
Die Antworten<br />
1b. Falsch: Alle führenden Szenarien prognostizieren einen Anstieg<br />
des globalen Energiebedarfs für die nächsten Jahrzehnte (2015<br />
bis 2040: zwischen 10 % und 40 %), der vor allem durch das<br />
Bevölkerungswachstum und die wachsende Nachfrage an<br />
Energie in den sich entwickelnden Ländern getrieben wird.<br />
2b. Falsch: Alle führenden Szenarien prognostizieren für die nächsten<br />
Jahrzehnte einen überpropor tio nalen Anstieg des weltweiten<br />
Strombedarfs (2015 bis 2040: zwischen 60 % und 80 %), der<br />
vor allem durch das Bevölkerungswachstum, die wachsende<br />
Nachfrage in den sich entwickelnden Ländern und dem heute<br />
fehlenden Zugang zu Elektrizität für etwa ein Drittel der Weltbevölkerung<br />
bedingt ist.<br />
3b. Falsch: Im Jahr 2017 stieg die weltweite Kohle förderung<br />
im Vergleich zum Vorjahr 2016 um 2 %.<br />
4c. Seit 2010 werden rund 11 % des weltweiten Strombedarfs<br />
in Kernkraftwerken erzeugt.<br />
5b. Rund 5 % des weltweiten Strombedarfs wurden 2017<br />
durch Wind (4 %) und Solarenergie (1 %) erzeugt.<br />
6c. USA mit rund 6.800 Mrd. t, davon 98 % Kohle;<br />
EU mit rund 530 Mrd. t, davon 95 % Kohle<br />
7d. China. Die Kohlendioxid-Emissionen sind doppelt so hoch wie<br />
die der USA und dreimal so hoch wie die aller 28 EU-Länder.<br />
8d. Wasserkraft, 4 bis 13 g CO 2 pro kWh.<br />
Wind und Atomkraft: ca. 8 bis 20 g CO 2 pro kWh.<br />
Photovoltaik: 35 bis 160 g CO 2 pro kWh.<br />
9a. Kernkraft, insbesondere kleine modulare Reaktoren<br />
mit fortschrittlichem Brennstoff.<br />
10d. Kernenergie. Die Anzahl der Ausfalltage pro Kilowatt stunde<br />
aus Kernenergie liegt im Bereich der Windkraft und<br />
etwa 5- bis 100-mal niedriger als bei jeder anderen<br />
Primärenergiequelle.<br />
11d. Die natürliche Strahlung, die Thorium und seine Zerfalls produkte<br />
in Guarapari (Monazit-Gebiet) verursachen, ist bis zu<br />
10.000-mal höher als die Strahlung aus Kernkraftwerken<br />
im Normalbetrieb.<br />
12b. Falsch: Weltweit sind 448 Kernkraftwerke in Betrieb und<br />
59 in Bau; rund 120 weitere Kraftwerke sind geplant.<br />
Nur einige Anlagen werden in den kommenden Jahren<br />
stillgelegt werden, vor allem in den “alten” Ländern.<br />
Weitere Ausbauprogramme werden verfolgt und umgesetzt,<br />
z.B. in China mit mehr als 100 Anlagen, die im Zeitraum<br />
2030 bis 2040 in Betrieb sein werden, sowie in den<br />
“Newcomer”-Ländern Asiens.<br />
Market data<br />
(All information is supplied without<br />
guarantee.)<br />
Nuclear Fuel Supply<br />
Market Data<br />
Information in current (nominal)<br />
U.S.-$. No inflation adjustment of<br />
prices on a base year. Separative work<br />
data for the formerly “secondary<br />
market”. Uranium prices [US-$/lb<br />
U 3 O 8 ; 1 lb = 453.53 g; 1 lb U 3 O 8 =<br />
0.385 kg U]. Conversion prices<br />
[US-$/kg U], Separative work<br />
[US-$/SWU (Separative work unit)].<br />
January to December 2013<br />
• Uranium: 34.00–43.50<br />
• Conversion: 9.25–11.50<br />
• Separative work: 98.00–127.00<br />
January to December 2014<br />
• Uranium: 28.10–42.00<br />
• Conversion: 7.25–11.00<br />
• Separative work: 86.00–98.00<br />
January to June 2015<br />
• Uranium: 35.00–39.75<br />
• Conversion: 7.00–9.50<br />
• Separative work: 70.00–92.00<br />
June to December 2015<br />
• Uranium: 35.00–37.45<br />
• Conversion: 6.25–8.00<br />
• Separative work: 58.00–76.00<br />
2016<br />
January to June 2016<br />
• Uranium: 26.50–35.25<br />
• Conversion: 6.25–6.75<br />
• Separative work: 58.00–62.00<br />
July to December 2016<br />
• Uranium: 18.75–27.80<br />
• Conversion: 5.50–6.50<br />
• Separative work: 47.00–62.00<br />
2017<br />
January 2017<br />
• Uranium: 20.25–25.50<br />
• Conversion: 5.50–6.75<br />
• Separative work: 47.00–50.00<br />
February 2017<br />
• Uranium: 23.50–26.50<br />
• Conversion: 5.50–6.75<br />
• Separative work: 48.00–50.00<br />
March 2017<br />
• Uranium: 24.00–26.00<br />
• Conversion: 5.50–6.75<br />
• Separative work: 47.00–50.00<br />
April 2017<br />
• Uranium: 22.50–23.50<br />
• Conversion: 5.00–5.50<br />
• Separative work: 45.50–48.50<br />
May 2017<br />
• Uranium: 19.25–22.75<br />
• Conversion: 5.00–5.50<br />
• Separative work: 42.00–45.00<br />
June 2017<br />
• Uranium: 19.25–20.50<br />
• Conversion: 5.55–5.50<br />
• Separative work: 42.00–43.00<br />
News
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
July 2017<br />
• Uranium: 19.75–20.50<br />
• Conversion: 4.75–5.25<br />
• Separative work: 42.00–43.00<br />
August 2017<br />
• Uranium: 19.50–21.00<br />
• Conversion: 4.75–5.25<br />
• Separative work: 41.00–43.00<br />
September 2017<br />
• Uranium: 19.75–20.75<br />
• Conversion: 4.60–5.10<br />
• Separative work: 40.50–42.00<br />
October 2017<br />
• Uranium: 19.90–20.50<br />
• Conversion: 4.50–5.25<br />
• Separative work: 40.00–43.00<br />
November 2017<br />
• Uranium: 20.00–26.00<br />
• Conversion: 4.75–5.25<br />
• Separative work: 40.00–43.00<br />
December 2017<br />
• Uranium: 23.50–25.50<br />
• Conversion: 5.00–6.00<br />
• Separative work: 39.00–42.00<br />
| | Source: Energy Intelligence<br />
www.energyintel.com<br />
Cross-border Price<br />
for Hard Coal<br />
Cross-border price for hard coal in<br />
[€/t TCE] and orders in [t TCE] for<br />
use in power plants (TCE: tonnes of<br />
coal equivalent, German border):<br />
2012: 93.<strong>02</strong>; 27,453,635<br />
2013: 79.12, 31,637,166<br />
2014: 72.94, 30,591,663<br />
2015: 67.90; 28,919,230<br />
2016: 67.07; 29,787,178<br />
I. quarter: 56.87; 8,627,347<br />
II. quarter: 56.12; 5,970,240<br />
III. quarter: 65.03, 7.257.041<br />
IV. quarter: 88.28; 7,932,550<br />
2017:<br />
I. quarter: 95.75; 8,385,071<br />
II. quarter: 86.40; 5,094,233<br />
III. quarter: 88.07; 5,504,908<br />
| | Source: BAFA, some data provisional<br />
www.bafa.de<br />
EEX Trading Results<br />
December 2017<br />
(eex) In December 2017, the European<br />
Energy Exchange (EEX) achieved a<br />
total volume of 234.5 TWh on its<br />
power derivatives markets (December<br />
2016: 287.4 TWh). The December<br />
volume comprised 160.8 TWh traded<br />
at EEX via Trade Registration with<br />
subsequent clearing. Clearing and<br />
settlement of all exchange transactions<br />
was executed by European<br />
Commodity Clearing (ECC).<br />
On the German power derivatives<br />
market, trading volumes in Phelix-<br />
DE Futures (72.9 TWh) exceeded<br />
| | Uranium spot market prices from 1980 to 2017 and from 2007 to <strong>2018</strong>. The price range is shown.<br />
In years with U.S. trade restrictions the unrestricted uranium spot market price is shown.<br />
| | Separative work and conversion market price ranges from 2007 to <strong>2018</strong>. The price range is shown.<br />
)1<br />
In December 2009 Energy Intelligence changed the method of calculation for spot market prices. The change results in virtual price leaps.<br />
Phelix- DE/AT Futures (66.0 TWh) for<br />
the first time. On the markets for Italy<br />
(50.0 TWh) and Spain (7.4 TWh),<br />
EEX recorded the highest monthly<br />
volume of the year 2017. Compared to<br />
the previous year, volumes in these<br />
markets increased by 43% (Italy) and<br />
10% (Spain). On the Dutch power<br />
derivatives market, trading volumes<br />
almost doubled to 1.8 TWh (December<br />
2016: 0.9 TWh).<br />
The Settlement Price for base<br />
load contract (Phelix Futures) with<br />
delivery in <strong>2018</strong> amounted to<br />
37.67 €/MWh. The Settlement Price<br />
for peak load contract (Phelix Futures)<br />
with delivery in <strong>2018</strong> amounted to<br />
46.80 €/MWh.<br />
On the EEX markets for emission<br />
allowances, 65.6 million tonnes of<br />
CO 2 were traded in December<br />
( December 2016: 117.6 million tonnes<br />
of CO 2 ). Primary market auctions<br />
contributed 45.0 million tonnes of<br />
CO 2 to the total volume.<br />
The EUA price with delivery in<br />
December 2017 amounted to<br />
7.10/8.21 €/ EUA (min./max.).<br />
| | www.eex.com<br />
MWV Crude Oil/Product Prices<br />
November 2017<br />
(mwv) According to information and<br />
calculations by the Association of the<br />
German Petroleum Industry MWV e.V.<br />
in November 2017 the prices for super<br />
fuel, fuel oil and heating oil noted<br />
slightly higher compared with the<br />
pre vious month October 2017. The<br />
average gas station prices for Euro<br />
super consisted of 138.54 €Cent<br />
( October 2017: 134.72 €Cent, approx.<br />
+2.84 % in brackets: each information<br />
for pre vious month or rather previous<br />
month comparison), for diesel fuel of<br />
118.52 €Cent (116.196; +2.01 %) and<br />
for heating oil (HEL) of 60.06 €Cent<br />
(57.07 €Cent, +5.24 %).<br />
The tax share for super with<br />
a consumer price of 138.54 €Cent<br />
(134.72 €Cent) consisted of<br />
65.45 €Cent (47.24 %, 65.45 €Cent)<br />
for the current constant mineral oil<br />
tax share and 22.12 €Cent (current<br />
rate: 19.0 % = const., 21.51 €Cent) for<br />
the value added tax. The product<br />
price (notation Rotterdam) consisted<br />
of 39.06 €Cent (28.19 %, 36.20 €Cent)<br />
and the gross margin consisted of<br />
11.91 €Cent (8.60 %; 11.74 €Cent).<br />
Thus the overall tax share for super<br />
results of 66.24 % (67.58 %).<br />
Worldwide crude oil prices<br />
(monthly average price OPEC/Brent/<br />
WTI, Source: U.S. EIA) were again<br />
higher, approx. +9.43 % (+3.27 %)<br />
in November compared to October<br />
2017.<br />
The market showed a stable<br />
development with higher prices; each<br />
in US-$/bbl: OPEC basket: 60.74<br />
(53.44); UK-Brent: 62.70 (57.51);<br />
West Texas Inter mediate (WTI):<br />
56.64 (51.58).<br />
| | www.mwv.de<br />
133<br />
NEWS<br />
News
<strong>atw</strong> Vol. 63 (<strong>2018</strong>) | Issue 2 ı February<br />
134<br />
NUCLEAR TODAY<br />
Links to reference<br />
sources:<br />
President Macron<br />
interview: http://<br />
reut.rs/2EIkEgM<br />
Trump on Iran: http://<br />
nyti.ms/2mF1Ecp<br />
UK statement on<br />
Euratom: http://bit.ly/<br />
2mGhrbf<br />
Author<br />
John Shepherd<br />
nuclear 24<br />
41a Beoley Road West<br />
St George’s<br />
Redditch B98 8LR,<br />
United Kingdom<br />
Playing Politics with Nuclear<br />
is All Part of the Game<br />
John Shepherd<br />
If a week is a long time in politics – a statement attributed to former British prime minister Harold Wilson – then what<br />
about a month, or several months? Just eight months ago, Emmanuel Macron was elected president of France. Among<br />
his portfolio of political pledges was one to respect reductions in the country’s nuclear park set out by his predecessor,<br />
Francois Hollande.<br />
Hollande’s administration had established an energy<br />
transition law which set a target of reducing the share of<br />
nuclear in France’s electricity mix to 50 % by 2<strong>02</strong>5 from<br />
around 75 %.<br />
Fast forward to November 2017 and Macron’s environment<br />
minister, Nicolas Hulot, admitted that this could not<br />
be done – at least in the timeframe envisaged – without<br />
pushing up CO2 emissions, endangering security of power<br />
supply and the not-so-insignificant matter of risking<br />
thousands of jobs. Instead, Hulot said the government<br />
would come up with a more “realistic” target.<br />
Now move forward into early <strong>2018</strong> and France has<br />
signed a deal for closer cooperation in the development of<br />
civil nuclear with the China National Nuclear Corporation<br />
(CNNC). The agreement, signed by Framatome and CNNC<br />
during Macron’s visit to Beijing in January, also renewed a<br />
contract under which Framatome will supply nuclear fuel<br />
components to CNNC.<br />
As Macron’s visit came to a close, he issued a joint statement<br />
with his Chinese counterpart, Xi Jinping, to express<br />
“their high appreciation of the active cooperation between<br />
the two countries in the field of civilian nuclear energy and<br />
support a deepening of cooperation in the entire nuclear<br />
cycle”.<br />
Now this was indeed good news. France has had more<br />
than its fair share of ups and downs in the state-backed<br />
nuclear sector in recent years. But it begs the question, why<br />
would Macron want to expand civil nuclear activities in<br />
cooperation with an overseas partner if, back home, the<br />
goal is to reduce the reliance on nuclear?<br />
The answer is politics. As Macron was quoted telling<br />
France 2 television in an interview last December: “I don’t<br />
idolise nuclear energy at all. But I think you have to pick<br />
your battle. My priority in France, Europe and internationally<br />
is CO 2 emissions and (global) warming.”<br />
A leader who certainly does not shy away from battles is<br />
US president Donald Trump, who has also had nuclear<br />
power in his sights – but he too gives mixed messages on<br />
nuclear.<br />
On the domestic front, President Trump has been<br />
outspoken in his support for the use of civil nuclear energy<br />
as indeed he has for rejuvenating his country’s coal<br />
industry. However, proposals that paved the way for the US<br />
to offer incentives to power plants such as coal and nuclear<br />
in a bid to improve the resilience of the nation's power grid,<br />
were recently rejected by federal energy regulators.<br />
But Trump’s reason for backing nuclear does not appear<br />
to be linked to a desire to help the climate – or maybe it<br />
does – depending it seems on his temperament from one<br />
day to the next. You will recall that he pulled the US out of<br />
the Paris climate accord reached on his predecessor’s<br />
watch.<br />
But then a few weeks ago Trump said the US could<br />
go “go back” into the Paris deal. “We could conceivably go<br />
back in... I feel very strongly about the environment,” the<br />
president said during a joint news conference with<br />
Norwegian prime minister Erna Solberg.<br />
In a related move, Trump has demanded that European<br />
allies agree to rewriting a deal struck with Iran in 2015 –<br />
which lifted economic sanctions in exchange for Tehran<br />
limiting its nuclear ambitions beyond power generation –<br />
otherwise he said the US would pull out of the deal in the<br />
coming months, effectively “killing it”.<br />
The UK is also attempting a balancing act on matters<br />
nuclear. The government has confirmed Britain will exit<br />
Euratom at the same time as it withdraws from membership<br />
of the European Union on 29 March 2019.<br />
Greg Clark, secretary of state for business, energy and<br />
industrial strategy, told parliament the government’s<br />
“No.1 priority is continuity for the nuclear sector”. Clark<br />
said: “It is vitally important that our departure from the EU<br />
does not jeopardise this success, and it is in the interests of<br />
both the EU and the UK that our relationship should<br />
continue to be as close as possible.”<br />
Tom Greatrex, chief executive officer of the UK's Nuclear<br />
Industry Association, warned that even with a suitable<br />
transition being negotiated for Britain’s exit from the EU<br />
there “remains much work for the government to do<br />
to prevent the significant disruption that industry is<br />
concerned about.”<br />
Greatrex is of course correct. The UK has barely limped<br />
through the first phase of talks relating to Brexit and time<br />
is not on the side of either party. So for a minister to be<br />
talking about leaving Euratom – while at the same time<br />
continuing to enjoy the benefits that Euratom brings the<br />
UK – is surprising to say the least.<br />
Of course all these political machinations could be<br />
applied to any sector or policy and in any country. But the<br />
nuclear industry has long accepted that it can be used as a<br />
political football, to be kicked into goal or off the pitch<br />
completely depending on the situation at hand.<br />
I am reminded of a quotation from Otto von Bismarck,<br />
the ‘Iron Chancellor’, who said: “Politics is the art of the<br />
possible, the attainable – the art of the next best.”<br />
No political leader wants the lights going off and<br />
hurting homes, hospitals and businesses while they are in<br />
charge. They also don’t want to be seen as responsible for<br />
driving up unemployment.<br />
In terms of nuclear, whether cheerleaders for the<br />
technology or not, as the French president said: “You have<br />
to pick your battle.” The nuclear industry is all too familiar<br />
with fighting battles – defending itself from attack while<br />
quietly going about its task of safely supplying clean<br />
electricity to power-hungry grids around the world.<br />
Our industry therefore has power in the political sense<br />
too, but with power comes responsibility – nuclear leaders<br />
know that only too well and now is as good as time as ever<br />
to lead by example.<br />
Nuclear Today<br />
Playing Politics with Nuclear is All Part of the Game ı John Shepherd
Kommunikation und<br />
Training für Kerntechnik<br />
International sicher agieren<br />
Seminar:<br />
Advancing Your Nuclear English (Aufbaukurs)<br />
Im internationalen Dialog ist Englisch die universelle Sprache. Dies gilt für Geschäfts beziehungen<br />
im Allgemeinen ebenso wie für die Branche der Kerntechnik im Speziellen. In Deutschland gewinnen<br />
der internationale Austausch und damit das Englische zudem durch die auf das Jahr 2<strong>02</strong>2 politisch<br />
begrenzte Stromerzeugung aus Kernenergie eine noch größere Bedeutung.<br />
Seminarinhalte<br />
ı Participating in an international conference for nuclear experts on “New products and processes”<br />
ı Before and during the conference<br />
ı Holding a town hall meeting in an international setting on “Safety issues at nuclear power facilities”<br />
ı Planning and conducting a town hall meeting<br />
ı After a town hall meeting<br />
Den Teilnehmerinnen und Teilnehmern wird über eine praxisorientierte Didaktik und unter der<br />
Verwendung „kerntechnischen Vokabulars“ das notwendige Know-how für den beruflichen Alltag<br />
vermittelt. Dabei gilt es sprachlich bedingte Kommunikationsbarrieren mit internationalem Kollegium<br />
und Kunden zu überwinden.<br />
Zielgruppe<br />
Diese 2-tägige Schulung richtet sich an Führungskräfte, Projektverantwortliche sowie Mitarbeiterinnen<br />
und Mitarbeiter aus allen Fachbereichen, bei denen Englisch für die organisationsinterne und/oder<br />
externe Kommunikation von Bedeutung ist.<br />
Maximale Teilnehmerzahl: 12 Personen<br />
Voraussetzungen<br />
Teilnehmerinnen und Teilnehmer sollten grundsätzliche Englischkenntnisse, in Form der Fähigkeit<br />
der allgemeinen Konversation in Wort und Schrift, mitbringen. Hierbei kann es sich um Kenntnisse<br />
handeln, die entweder während der Schulzeit bzw. während der Ausbildung/des Studiums oder<br />
aber berufs begleitend erworben wurden. (CEFR: etwa Niveau B1/B2).<br />
Referentin<br />
Devika Kataja<br />
Konferenzdolmetscherin, Fachübersetzerin und Sprachtrainerin (English Native Speaker)<br />
Wir freuen uns auf Ihre Teilnahme!<br />
Termin<br />
2 Tage<br />
11. bis 12. April <strong>2018</strong><br />
Tag 1: 10:30 bis 17:30 Uhr<br />
Tag 2: 09:00 bis 16:30 Uhr<br />
Veranstaltungsort<br />
Geschäftsstelle der INFORUM<br />
Robert-Koch-Platz 4<br />
10115 Berlin<br />
Teilnahmegebühr<br />
898,– € ı zzgl. 19 % USt.<br />
Im Preis inbegriffen sind:<br />
ı Seminarunterlagen<br />
ı Teilnahmebescheinigung<br />
ı Pausenverpflegung<br />
inkl. Mittagessen<br />
Kontakt<br />
INFORUM<br />
Verlags- und Verwaltungsgesellschaft<br />
mbH<br />
Robert-Koch-Platz 4<br />
10115 Berlin<br />
Petra Dinter-Tumtzak<br />
Fon +49 30 498555-30<br />
Fax +49 30 498555-18<br />
seminare@kernenergie.de<br />
Bei Fragen zur Anmeldung<br />
rufen Sie uns bitte an oder<br />
senden uns eine E-Mail.
The International Expert Conference on Nuclear Technology<br />
Outstanding Know-How<br />
and Innovations<br />
Insights<br />
on AMNT<br />
Watch the video:<br />
http://youtu.be/<br />
DDC3L3XhnoA<br />
The AMNT <strong>2018</strong> offers a great variety of high level sessions in the fields<br />
of know-how, innovations and regulation. International speakers<br />
will discuss current issues and relevant developments. Expand your<br />
professional network in meetings with experts and decision-makers<br />
working in industry, utilities, research and development as well as<br />
politics and administration.<br />
Sessions<br />
3 International Regulation – Radiation Protection:<br />
The Implementation of the EU Basic Safety Standards Directive 2013/59<br />
and the Release of Radioactive Material from Regulatory Control<br />
3 Safety of Advanced Nuclear Power Plants<br />
3 Know-How, New Build and Innovations<br />
3 Reactor Physics, Thermo and Fluid Dynamics<br />
3 Young Scientists’ Workshop<br />
3 Nuclear Energy Campus<br />
Outstanding<br />
Know-How &<br />
Sustainable<br />
Innovations<br />
Enhanced<br />
Safety &<br />
Operation<br />
Excellence<br />
Decommissioning<br />
Experience &<br />
Waste Management<br />
Solutions<br />
Don’t miss this key event of the global nuclear energy community.<br />
29 – 30 May <strong>2018</strong><br />
Estrel Convention Center Berlin<br />
Germany<br />
www.nucleartech-meeting.com