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| process heat applications |
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| The development of advanced higher temperature nuclear reactors
creates the means to expand the use of nuclear energy into a variety
of industrial and transport sectors (in addition to electricity generation),
by supplying clean process heat to produce chemical products, liquid
petroleum fuels and hydrogen. The nuclear heat source must still meet
modern reactor design standards, be economic, match the process technical
needs and reliably produce the required temperatures. |
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| South Africa’s Pebble Bed Modular Reactor (PBMR) technology
fits each of these requirements. Because of its very high reactor
outlet temperatures of up to 950°C, the heat from the PBMR can
be applied for a variety of industrial process applications. For example,
the PBMR produced steam can be used to extract oil from Oil Sands,
and for many other petrochemical industrial applications where fossil
fuels are currently used as the primary source of process steam. Alternatively,
the PBMR produced hydrogen can be used for upgrading coal and heavy
crude oils into usable products or for transportation fuel in the
future, thereby relieving pressure on natural gas supply (the source
of most hydrogen produced today). |
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| These applications were investigated with potential customers
in global markets by the PBMR based team led by PBMR, Westinghouse
and Shaw. Pre-conceptual work has confirmed that the reactor design
developed for power plant applications can be readily integrated into
process heat applications. The characteristic robustness and flexibility
of the core design means that only minimal modifications to interfaces
are necessary to meet a broad range of process heat application requirements.
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| The schematic shows one such PBMR Process Heat configuration. The
hot helium exits the bottom of the reactor and passes through helium-to-helium
intermediate heat exchangers (IHXs); circulators located on top of
the heat exchangers drive the gas back into the reactor inlet. Helium
in an intermediate loop (not shown) transfers the heat to the process
application via the concentric pipes shown. Requirements for the IHX
will be similar to those for compact heat exchangers being developed
for the South African Demonstration Power Plant (DPP). |
| Two PBMR process heat configurations are currently defined: the
first generates intermediate temperature helium (in the 750°C
range) for high pressure steam production with cogeneration; the second
can deliver high temperature helium at up to 950°C for high temperature
process applications (notably steam methane reforming, high temperature
steam electrolysis and thermo-chemical processes for hydrogen production).
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| Why PBMR for process heat? |
| PBMR technology has unique features which make it well-suited as
heat source for process applications: |
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- Access to high-temperature process heat markets due to its ability
to provide process temperatures up to 900°C (reactor outlet
of 950°), plus cogenerated power and/or low temperature desalination
processes.
- Well-matched to industrial process sizes, up to 500 MW(t)
- Ability to co-locate with industrial process plants due to enhanced
safety characteristics and small exclusion zone.
- Deployment within a decade since it builds on the development
and design work carried out on the South African Demonstration
Power Plant (DPP) initiative.
- Economic benefits include displacement of premium fossil fuels,
value from avoided CO2 emissions, high reliability, improved availability
due to continuous online refueling, short construction times and
reduced financing costs during construction.
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| Product Range |
| The South African PBMR project entailed the design and construction
of a 165 MW(e)/400 MW(t) power plant at Koeberg near Cape Town and
a fuel plant at Pelindaba near Pretoria. The DPP intended to demonstrate
the combination of the PBMR reactor with a full-scale Brayton cycle
gas turbine as the basis of the proposed multi-module electricity
plant. It is this development program that provided the technology
platform for the Process Heat Plants (PHPs). |
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| The PHPs will be based on the DPP reactor design; and core dimensions
will be kept the same for different process heat applications by designing
for a standardized fleet enveloping a range of requirements. The PHP
was intended to operate at power levels of up to 500 MW(t) with reactor
outlet temperatures up to 950°C. Process steam delivery is the
near-term entry market application with hydrogen delivery as the follow-on.
Hence, development work is focused on two time frames and technology
windows: |
- Applications operating at reactor outlet temperatures less than
800°C to produce high-pressure steam and cogeneration. Component
engineering development requirements and application integration
engineering requirements are such that deployment in a decade will be feasible.
- The follow-on development phase, focusing on the next decade, will meet
the requirements for operating at reactor outlet temperatures up to 950°C.
This phase matches timeframes for associated developments in high-temperature
materials and hydrogen production processes including thermo-chemical
water-splitting processes.
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| Value proposition |
| Attractive applications for nuclear process heat are driven primarily
by the opportunity to displace natural gas and other premium fuels,
and to respond to incentives to reduce CO2 emissions. Even with conservatively
low forecasts for growth in long-term gas prices, clear commercial
benefit exists in reducing exposure to the volatility and insecurity
of single sources of energy supply. Economic assessments of PBMR process
heat applications, based on current trends, indicate that PBMR will
be competitive in many markets, especially markets with high premium
fuel costs and CO2 emission constraints. |
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| Work ongoing and completed |
| Based on collaborations with several potential users of this technology,
PBMR and its partners in the nuclear and process industry have initiated
and completed several initiatives including: |
- Preliminary definition of process heat delivery systems
for intermediate and high temperature applications
- Survey
of high temperature process applications and economics
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Initiation of pre-licensing initiatives in the US and Canada to prepare
for early projects
- Cooperation with universities to support
application and market studies, support energy policy development,
and establish outreach programs
- Initial information exchange
with government agencies developing energy policy and nuclear policy
- Definition of first of fleet projects and project requirements
- Development of project implementation requirements and planning
- Economic analysis of various applications
- Quantification
of long term technology benefits in terms of CO2 and natural gas displacement
- Formation of an industry advisory group
- Definition
of technology development needed for various hydrogen applications
- Definition of industrial nuclear cogeneration and desalination
plant configurations
- Definition of oil sands in-situ and
surface mining nuclear cogeneration configurations
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| In South Africa and elsewhere, application studies have confirmed
the potential for integrating the PBMR into process plants to meet
process steam and electricity demands. In Canada, there is interest
from the oil sands industry in using the PBMR to produce steam at
the temperature and associated pressures needed for “in-situ”
applications to extract bitumen from oil sands displacing intended
gas-fired plants that are currently used. |
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| In the USA, PBMR, Westinghouse and Shaw were the lead principles
in a world class team advancing the Next Generation Nuclear Plant
(NGNP) Project, which is based on developing and demonstrating HTGR
technology for a broad range of industrial process heat applications,
including hydrogen production.
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