Nuclear Plant Journal - Digital Versions

Road Map..
Continued from page 54
The utilization of nuclear energy in
such countries will require infrastructure
building and institutional arrangements
for issues such as financing, liability,
safeguards, safety, and security.
District Heating
District heating involves the supply
of space heat and hot water through a
district heating system, which consists of
heat plants (usually producing electricity
simultaneously) and a network of
distribution pipes. Potential application of
district heating is in climatic zones with
relatively long and cold winters. In many
countries, such as central and northern
Reactor
Type
European countries and countries in
transition economies, district heating has
been widely used for decades.
Coal and gas dominate the fuels used
for district heating. However, several
countries (Bulgaria, China, Czech Republic,
Hungary, Romania, Russia, Slovakia,
Sweden, Switzerland and Ukraine) have
experience in nuclear district heating using
water-cooled reactors, so the technical
aspects can be considered well proven.
In order to be able to compete with
Location m 3 /day Status
fossil-fuel-fired heat boilers, the capital cost
per installed MW of heat production capacity
for a nuclear-based system must be such
that the production costs are competitive.
Dedicated reactors providing district heat
can potentially achieve acceptable costs,
due to their lower temperature operating
conditions, simple design, modularization
and standardization, and advanced safety
systems.
New nuclear heat-producing plants
must, of course, meet the user’s requirements
on availability and reliability, including
alternative heat-producing capacity that
could serve as backup. For this purpose,
heat storage allows a matching of the heat
supply to the heat demand. Today there are
many examples of short-term storage, for
instance, on the daily scale that relies on
hot water accumulator tanks. In the future,
more long-term storage facilities may be
realized.
Table 1: Reactor types used or under construction for seawater desalination
LMFR Kazakhstan (Aktau) 80,000 In service till 1999
PWRs
HWRs
Japan
Ohi 1,2,3,4
Takahama
Ikata 1,2,3
Genkai 3,4
USA (Diablo
Canyon)
~1500 In service
Operating experience ~
170 R-Ys
~4500 In service
India (Madras) 6,300 RO commissioned in
2002
MSF to be commissioned
in 2008
Pakistan
(KANUPP)
4,800 Under construction;
Commissioning –in 2008
Industrial Heat Process
Process heat involves the supply of heat
required for industrial processes from one
or more centralized heat generation sites
through a steam transportation network.
Within the industrial sector, process heat
is used for a large variety of applications
with different heat requirements and
with temperature ranges covering a wide
spectrum. Examples of industries that
consume considerable amounts of heat
are:
• food,
• paper,
• chemicals and fertilizers,
• petroleum and coal processing, and
• metal processing industries.
The chemical and petroleum industries
are the major consumers of process heat
worldwide. These would be key target
clients for possible applications of nuclear
energy.
The supply of energy for industrial
processes has an essential character: all
industrial users need the assurance of
energy supply with a high reliability, and
the heat should be produced close to the
point of use. Many of the process heat
users, in particular the large ones, usually
are located outside urban areas, often at
considerable distances. This makes joint
siting of nuclear reactors and industrial
users of process heat not only viable, but
also desirable in order to drastically reduce
the heat transportation costs.
The nuclear process heat supply has
to be reliable. As an example, the average
steam supply availabilities for chemical
processing and oil refineries are 92% and
above.
There is experience in providing
process heat for industrial purposes with
nuclear energy in Canada, Germany,
Norway, Switzerland, and India. New
plant designs that can provide heat, or both
heat and electricity, are being designed in
Russia, the Republic of Korea, Canada, and
other countries.
Current water cooled reactors can
provide process heat up to about 300ºC,
and some future innovative water cooled
reactor designs 2 have potential to provide
heat up to approximately 550ºC.
Although nuclear industrial process
heat applications have significant potential,
it has not been realized to a large extent.
In fact, currently only the Goesgen reactor
in Switzerland and the RAPS–2 reactor in
India continue to provide industrial process
heat, whereas other nuclear process heat
systems have been discontinued after
successful use. Among the reasons cited for
closure of these units, one is availability of
cheaper alternate energy sources.
For potential future application of
nuclear process heat, an important example
2
Specifically Super-critical Water Cooled Reactors,
being developed within the Generation-IV
International Forum, could be deployed by around
2025-2030.
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