VGB POWERTECH 7 (2020) - International Journal for Generation and Storage of Electricity and Heat

Abstracts VGB PowerTech 7 l 2020
Technical risk management
of hydropower plants
Wolfgang Hamelmann, Klaus Engels
and Peter Struckmann
When operating and maintaining a large portfolio
of hydropower assets, the challenge for the
owner and operator is to decide which risk mitigation
investments and maintenance activities
should come first, and when. This is especially
true when resources in personnel and budgets
are limited, and the profitability of the plants
must be optimized. The situation requires an
efficient and rational prioritization of activities
and corresponding allocation of budgets.
But how can the right criteria and investment
principles be determined, if the overall target
is safe, reliable, compliant and economical operation
of plants? This article outlines how an
asset risk management system can assist in this
determination.
Optimised maintenance strategies
in thermal waste utilisation
Artificial intelligence and high quality key
performance indicators increase availability
Mariusz Maciejewski and Harald Moosandl
Currently, thermal waste treatment plants are
virtually used to capacity, mostly operating at
maximum utilization capacity. After technical
optimizations in recent years, in most cases a
further increase in the throughput can only
be achieved by increasing the hours of operation
and thus reducing the downtimes. First
of all, these goals can be achieved by means of
optimized strategies like a predictive and thus
condition-based maintenance. An innovative
system of STEAG Energy Services GmbH (SES)
that MVV Umwelt, one of Europe’s leading
companies of the industry, uses in their plants,
already shows how innovative and powerful
methods can be used in practice. A fundamental
prerequisite for this is a continuous process
quality and condition monitoring of plants and
components in thermal waste treatment plants.
Here a central challenge consists in the task to
reliably identify abnormalities and also creeping
changes from the vast amount of process
data provided by modern control systems in
order to react early and thus in time. Methods
for the physical modeling in predictive maintenance
create a crucial basis for this. Moreover,
groundbreaking technologies like Big Data and
machine learning in combination with AI methods
allow to largely automate the procedures
for the modeling and thus the determination of
reference values for the real-time monitoring of
thermal waste treatment plants. After all, especially
the users and thus the operation management
and maintenance in thermal waste treatment
plants benefit from such developments.
Refractory linings under
thermomechanical aspects
Holger Leszinski and Martin Breddermann
The design of refractory structures is usually
based on requirements that must be matched
to the expected furnace atmosphere: Tightness,
thermal and chemical compatibility, minimization
of heat losses, etc. In this respect, the experience
of the constructor and heat transfer calculations
on the regular layer structure are supposed
to ensure that the completed system can
be relied upon. In contrast, comparatively little
attention is paid to thermomechanical processes.
Often it is constraint stresses – during operation
caused by hindrance of temperature deformation
and sometimes many times higher than
stresses due to dead loads or internal furnace
pressure – which can “bring furnace components
to their knees”. Even after the occurrence
of such failures, the causes are often sought in
the wrong direction, among other things because
the thermomechanical interactions of
the individual structural components are not
known or are underestimated. Of course, it is
only possible to approximate the complex of
refractory construction with its innumerable
imponderables, also from a thermomechanical
point of view; for this, in the given article the
basic mechanisms are explained, exemplary
thermomechanical considerations of various
design examples are shown, and the possibilities
for optimizing safety and service life that
can be concluded from this are presented.
Thermal turbomachinery
Consulting services for the plant operator
Gerald Kulhanek, Michael Schwaiger,
Dominik Franzl and Leonhard Franz Pölzer
Thermal turbomachines are the core component
of many industrial plants. After the occurrence
of damage, during revisions/overhauls,
in the case of large revamp/retrofit projects or
for new acquisitions, plant operators are often
interested in obtaining consulting services from
external consulting companies for a limited period
of time. In recent years and decades, the
turbomachinery market has been characterized
by major changes. Turbine manufacturing plants
have been shut down or restructured and tasks
have become more and more challenging due
to new regulations and laws. At the same time,
it is becoming increasingly difficult for turbine
manufacturers and plant operators to retain or
attract skilled workers and experts. This creates
a demand for independent technical consulting
services in the field of thermal turbomachinery.
This paper defines and describes the essential
requirements that a turbomachinery consulting
team should meet in order to ensure a sustainable
partnership with a plant operator. Based on
many years of practical experience, the range of
tasks for which the use of consulting services in
the field of thermal turbomachinery has proven
its worth is presented, as well as the developed
solution methods.
Statement on the IT Security Act 2.0
Stefan Loubichi
The threat situation in IT/OT-security as well
as cyber-security in the energy sector remains
high. We don´t know who exactly the cyber
terrorist / cyber criminals are, what they are
planning and that their next goals are. We only
know from the annual cyber attacks in Ukrainian
power grids or SCADA systems worldwide
that they could realize a blackout. With the
IT-security law (published in 2015) our government
took a courageous step in 2015 to protect
our critical infrastructure. Unfortunately, in
Germany we have lost leadership in this area in
terms of IT-/OT-security and have not adopted
an audit program for energy producers until
now. In this article the draft of the ITR-security
law 2.0, published in May 2020, is presented.
It is anticipated that the draft will enter into
force with slight changes by the end of the year.
Operators as well as manufacturer of core components
have to deal with new (legal) requirements
for their IT-/OT-systems. What they have
to do and which consequences they have to expect
if they do not implement the requirements
are presented in this article. Of course, there is
still room for improvement in our IT-security
law 2.0. But the new IT-security law 2.0 will
help us to achieve security for tomorrow.
The Biofficiency Project Part 1:
Handling ash-related challenges in
biomass-fired cogeneration plants
Lynn Hansen, Thorben de Riese,
Richard Nowak Delgado, Timo Leino,
Sebastian Fendt, Pedro Abelha, Hanna Kinnunen,
Partik Yrjas, Flemming Frandsen, Bo Sander,
Frans van Dijen and Hartmut Spliethoff
The EU funded project Biofficiency developed
a blueprint for the next generation of biomassbased
cogeneration plants using difficult fuels
while assuring a secure and nearly carbonneutral
power generation. In this first part of a
series of two publications, a summary of the activities
handling ash-related challenges in biomass
boilers is provided. Three thermochemical
pre-treatment technologies, torrefaction, hydrothermal
carbonisation and steam explosion
proved suitable for upgrading residual biomass
feedstock by increasing energy densities and
improving storage as well as handling properties.
In combustion tests, both in pulverised fuel
(PF) and fluidised bed (FB) systems ash-related
problems, namely deposit build-up, fine particle
formation and corrosion were examined.
Deposit tests in PF boilers showed that the additives
have a pronounced effect on deposit propensity,
the additive amount being of greater
importance than the type of additive. The use of
additives also showed positive influence on aerosol
formation. In FB firing, an optimisation of
the additive composition and insertion was performed,
where elemental sulphur was found to
be the most cost-effective additive for this case.
It was demonstrated that pre-treating straw by
torrefaction combined with a washing step requires
a substantially lower amount of additive
to be added during combustion. Biomass ashes
from different sources were classified based on
their composition and possible utilisation pathways
with the goal to avoid landfilling were
developed. Innovative utilisation options were
identified such as utilisation in construction materials
or recovery of valuable elements.
A journey through 100 years VGB
| Hydropower
Development Potential of Hydro-electric
Power
E. Göde
Hydro-power: Challenges in Europe
Michel Vogien und Hans Peter Sistenich
Maintaining Know-how and Assuring
Quality in Hydro Power Plants
Josef F. Ciesiolka and Hans-Christoph Funke
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