Terrestrial Energy innovates on molten salt reactor design for faster development and easier regulatory approvals

Here is information from an October 2016 Terrestrial Energy presentation on their Integral Molten Salt Reactor

Introduction to Terrestrial Energy
• Terrestrial Energy
• Commercializing a SMR for 2020s deployment
– Cost-competitive with fossil fuel combustion
– Ideal for industrial heat and SMR markets
• Technology – next generation Molten Salt Reactor (“MSR”)
• Proprietary MSR design – the Integral Molten Salt Reactor (“IMSR™”)
• High technology readiness
• Conducting basic/preliminary engineering work
– Concludes with construction and licensing of the first commercial IMSR power plant (400 MWth reactor)
• IMSR development and deployment
• Supported by power utility industry and senior executives, industrial companies, environmentalists and the Canadian Government and DOE
• Commenced VDR with Canadian Nuclear Safety Commission (“CNSC”)
– First MSR vendor to commence regulatory process
• Terrestrial Energy is a leading advanced reactor developer in a fast developing cleantech sector

Advantages of Molten Salt Reactors
• Safety
• Enhanced ability for passive decay heat removal
• Inherent Stability from strong negative reactivity coefficients
• Low pressure and no chemical driving force
• Caesium and Iodine stable within the fuel salt
• Reduced Capital Cost
• Inherent safety can simplify entire facility
• Low pressure, high thermal efficiency, superior coolants (smaller pumps, heat exchangers). No complex refuelling mechanisms
• Long Lived Waste Issues
• Ideal system for consuming existing transuranic wastes
• Even MSR-Burners can close fuel cycle and see almost no transuranics going to waste
• Resource Sustainability and Low Fuel Cycle Cost
• Thorium breeders obvious but MSR-Burners also very efficient on uranium use

Terrestrial Energy Integral Molten Salt Reactor
• LEU fueled MSR-Burner design like the 1980 DMSR
• Integrates all primary systems into a sealed reactor Core unit
• 7 year Core unit “Seal and Swap” approach to graphite lifetime
• Shorter lifetime for vessel and HX simplify qualification
• Planned as 400 MWth (~ 192 MWe)
• Alternate salt and new off gas system
• New passive decay heat removal in situ without dump tanks
• Safety at forefront which leads to cost innovation

In-situ Decay heat removal – New Innovation
• Freeze Valve and Dump Tank the “traditional” approach
• Results in unwanted lower penetrations and regulator likely to
assume failure to drain is possible
• IMSR approach has long been in-situ decay heat removal
• Convection and natural circulation brings decay heat to vessel wall
• Radiant transfer to Guard Vessel (Guard=Containment)
• 700 C surface 9x radiant heat compared to 300 C
• From there, water jacket options or PRISM type RVACS
• Reactor Vessel Auxiliary Cooling System

Terrestrial Energy’s new “IRVACS”
• IMSR utilizes a new innovative concept, proving extremely robust
• Basic concept is a closed cycle innovation of RVACS that retains a further barrier to the outside world
• New “Internal” RVACS or IRVACS moves heat by a closed cycle flow of nitrogen to a false roof acting as a large heat exchanger above the structural roof
• “Fails Better” If roof penetrated, outside air improves performance
• Modeling (including 140 million mesh CFD) showing excellent behavior for even most severe accident scenarios of losing all secondary heat transfer

Challenges solves with IMSR
• “Sealed for life” offers enormous regulatory advantages to accelerate development
• Airborne release risk during graphite swap eliminated
• Long cool down time before moving unit
• Material lifetime and corrosion issues greatly eased
• Good fuel economy on Once Through
• Future recycling to “close” fuel cycle and improve fuel economy commercially attractive
• Offers obvious “razor blade” analogy of continuous sales to attract industrial partners

About The Author

Add comment

E-mail is already registered on the site. Please use the Login form or enter another.

You entered an incorrect username or password

Sorry, you must be logged in to post a comment.