Futuretech Alert

(TechVision)

Generation IV Nuclear Reactor Technology

D835- TV

April 2016

“Developing Safer and More Reliable Nuclear Power”

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Contents

Section Slide Numbers

Generation IV Nuclear Reactors 4

Technology Background 5

Key Features of Generation IV Reactors 6

Drivers For Generation IV Reactors Development 7

Challenges for Generation IV Reactors Development 8

Region-wise Technology Development Scenario 9

Key Programs and Innovations in Generation IV Nuclear Reactors 10

Travelling Wave Sodium Cooled Fast Reactors 11

Integral Molten Salt Reactor 12

Next Generation Nuclear Plant 13

Korean Advanced Nuclear Reactors 14

Stable Salt Reactor 15

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Contents

Section

Slide Numbers

European Sustainable Nuclear Industrial Initiative 16

The Road Ahead 17

Technology Roadmap 18

Appendix 19

Key Patents 20

Key Contacts 23

4

Generation IV Nuclear Reactors

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Technology Background

Generation IV nuclear reactors are the conceptual reactors which are still in design phase and are expected to be commercialized by

2030. These reactors are expected to improve the power yield from nuclear reactors, safety of the reactors, and the ability to reuse the

existing nuclear waste as fuel. They differ from the previous generation reactors by refraining from using pressurized cooling and heat

transfer systems. They also have been developed to minimize the use of water as coolant in reactors to enable better thermal recovery

at reduced pressure.

In 2002, The Generation IV International Forum (GIF) classified six

nuclear reactors as generation IV technologies. These reactors can

be classified into two broad categories:

• Thermal reactors

• Fast reactors

Thermal reactors use slow or low velocity thermal neutrons to enable

fission. They use moderators to slow down the neutrons such as

graphite.

Fast reactors do not need moderators to control the velocity of the

neutrons.

Of the six chosen technologies VHTR is considered as pure thermal

reactor. The Supercritical Water Cooled reactor and Molten Slat

reactor may be used as either thermal or fast neutron reactors.

The reactor types being considered are

• Very high temperature reactor ( Thermal)

• Molten salt reactor (Thermal/ Fast)

• Supercritical water cooled reactor (Thermal/ Fast)

• Gas cooled fast reactor (Fast)

• Sodium cooled fast reactor (SCFR)/sodium fast reactor

(SFR) (Fast)

• Lead cooled fast reactor (LCFR)/lead fast reactor (LFR)

(Fast)

The main aim behind creating these reactors is to enable closed

nuclear fuel cycle where the spent nuclear fuel is reprocessed

and used again.

Nuclear Fuel Cycle:

• Nuclear fuel cycle defines the stages through which

the fuel goes through, from mining to disposing the

used fuel.

• The spent fuel may be reprocessed and reused

(closed cycle) or may be disposed after a single use

(open cycle).

• Reprocessing involves getting fissile materials from

the spent fuel materials.

• One advantage of reprocessing is that it reduces the

time the refuse takes for decaying to harmlessness.

• Employing closed cycle makes nuclear energy as a

renewable source and also makes the process

safer and cost effective.

• Most of the reactor models selected by the GIF are

based on closed cycle operation.

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Key Features of Generation IV Reactors

Gas Cooled Fast Reactors:

• They are high temperature gas cooled reactors and employ closed

fuel cycle.

• They bring in the advantages of fast reactors and high temperature

reactors.

• Disadvantages include rapid heating up of core in the absence of

forced cooling.

• The reactor is expected to be put to demonstration by 2020.

Generation IV Fast Reactors Generation IV Thermal Reactors

Lead Cooled Fast Reactors:

• These fast neutron reactors will employ lead or alloys such as lead-

bismuth eutectic as coolant.

• Both lead and bismuth have low neutron absorbing capability making

them ideal for the usage.

• Operating temperatures above 800 degrees C enable the

thermochemical production of hydrogen although the corrosive

properties of lead at these temperatures must be dealt with. Molten Salt Reactors:

Two variants of this reactor are available.

• In variant one, the fissile material itself is dissolved in the

molten fluoride salt and circulated through channels

made of graphite.

• In the second one, the molten salt acts as the coolant

alone and the fuel is in solid form, similar to those used

in VHTRs.

• The molten salt reactor may be either fast or thermal based on

the core design.

Sodium Cooled Fast Reactor:

• Molten sodium is used as the coolant enabling a system with low

coolant pressure.

• This also helps achieving high power density and electricity

generation is enable through a secondary coolant circuit.

• Operation temperatures are around 500 degrees C to 550 degrees C.

Supercritical Water Cooled Reactor:

• The reactor operates at very high temperature and pressure

values well above the critical point of water.

• Supercritical water (25 megapascal and 500 degrees C to 600

degrees C) is used to drive the turbine associated with

electrical generation.

• Reactor may be thermal reactor or fast neutron one based on

the core design.

Very High Temperature Reactor (VHTR):

• This is a high temperature reactor with gas cooled core.

Graphite is used as moderators and helium can be used as the

coolant.

• Can be used to generate both heat and electricity with high

efficiency.

• One of the safest reactor models to be developed.

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Source: Frost & Sullivan

The need for cleaner and

a sustainable source of

power

Safer than the previous

generation reactors

Resistance against

proliferation

Need to adopt safer

nuclear technologies

Better power density and

generation

Generation IV nuclear reactors are mostly fast neutron reactors. The fast neutrons used are capable of splitting the

Uranium 238 atoms, which make up more than 99% of the fuel used. The generation IV reactors thus enable efficient

fuel usage and also makes the fuel disposal less frequent due to the reuse of the U-238 atoms.

Using reprocessed and recycled spent fuel reduces the amount of radioactive waste disposed from the reactors to a

great extent. Thus the generated waste remains radioactive for a shorter period of time. These time periods are much

lesser than how long the wastes from existing nuclear plants and technologies remain radioactive.

These reactors enable reprocessing of the spent fuel to a great extent. Almost all the generation IV reactors can be

powered and run by using the recovered and reprocessed actinides and the spent fuel matrices. This makes them

more efficient and cost effective and also enhances the life of the plant.

The need for safer and more efficient reactors is an essential factor that can determine the future of nuclear power

this point forward. With most countries planning to reduce their dependence on nuclear power a better and safer

reactor may change the outlook aiding the adoption rate considerably.

The Generation IV nuclear reactions can generate more power than the contemporary technologies. This can be

attributed their ability to use the Uranium reserves much efficiently than the slow neutron reactors.

Drivers For Generation IV Reactors Development

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Source: Frost & Sullivan

Global outlook toward

nuclear power

Maturity level of

technologies

Cost of development

Adoption technologies

deployable in the near

term

Availability of Cost-

effective renewable

sources

With recent meltdowns in Japan, the general public is apprehensive toward nuclear power. This apprehension will be

one major barrier authorities will be facing in the future while deploying these technologies. Hence, creating

awareness among the people regarding the benefits and safety of generation IV reactors has become highly

necessary.

The technologies are still under development and actual results are yet to be seen. Though there have been some

demonstrations about their capability, the actual products are yet to developed and the proposed time frame for the

same is between 2020 to 2030. Long time frames could delay adoption of these technologies.

Governments are more interested in encouraging research in energy solutions those will be commercially available

within 2 to 5 years. Such a funding attitude is seen in most developing countries toward funding researches related to

technologies that will not be commercialized in the near future.

Research to develop renewable energy solutions especially solar cells is yielding better results and newer products

with better efficiency. The funding demanded by the research is also much less when compared to Generation IV

reactors.

Challenges for Generation IV Reactors Development

Genration IV reactors require a lot of funding for research, development, and deployment. This could be prohibitively

high for developing countries, thereby preventing active participation from them.

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Asia

• Countries such as Russia,

China, and South Korea

are interested in

developing Generation IV

reactors.

• China is developing

‘sodium cooled fast

reactors’ and has also

announced plans to

establish ‘supercritical

water cooled reactors’ by

the mid 2020s.

• South Korea has exhibited

interest in electro refining

and fuel reprocessing.

• It is also involved in

developing two different

Generation IV reactors.

• Institutions such as

Rosatom of Russia,

Korean Atomic Energy

Research Institute (KAERI)

are involved in developing

Generation IV reactors and

related technologies.

Region-wise Technology Development Scenario

Europe:

• European Union has a number reactor of programs

announced by governments.

• French Alternative Energies and Atomic Energy

Commission has announced the Advanced Sodium

Technological Reactor for Industrial Demonstration

(ASTRID) program to develop ‘sodium cooled fast

breeder reactors.’

• Belgian Nuclear Research Center has been working on

the Multi-purpose hYbrid Research Reactor for High-

tech Applications (MYRRHA), which is a lead cooled

fast reactor.

North America

• North America has the most

number of companies involved in

developing generator IV reactors.

• Government participation to

develop generation IV reactors

also is very high in the US.

• The US Department of Energy

(DOE) has announced $6 million

funding each to Southern

Company Services and X-

energy to develop advanced

nuclear reactor solutions such as

molten chloride fast reactor.

• DOE has also initiated a number

of programs such as Advanced

Reactor Concepts (ARC), and

Advanced Small Modular Reactor

(aSMR) program to develop

Generation IV reactors and

technologies aiding their adoption.

• Companies such as Transatomic

Power USA, Terrestrial Energy

Canada are involved.

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Key Programs and Innovations in Generation IV

Nuclear Reactors

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• TerraPower projects its travelling wave reactor technology as the most secure and the most proliferation resistive among

the available Generation IV technologies. The TWR technology is considered safe as it does not require the spent fuel to

undergo any reprocessing and enrichment processes, bringing down the chances for proliferation.

• The company has claimed that their TWR can enable its users to achieve 50 fold gain with respect to fuel efficiency and

usage.

• Converts the depleted uranium to usable fuel as the operation continues, making the process sustainable in true sense.

This also increases the resource efficiency and availability.

• TerraPower has partnered with Kobe Steel Ltd., Japan, to develop a steel alloy, which will be used in packaging of

materials, ducts, and tubes in reactors.

• TerraPower has partnered with the Scientific Research Institute of Atomic Reactors of Russia for establishing an

irradiation fuel program for the development of TWR. It has also partnered with Ion Beam Laboratory at the University of

Michigan to infuse new features to the HT-9 steel alloy used in fast breed reactors.

• The company aims at developing a 600 megawatt prototype between 2025 to 2030.

• Terra Power is a Washington-based nuclear reactor company that is involved in developing a sodium-cooled fast reactor. It is

developing the reactor based on the travelling wave reactor design.

• The company was started in 2008 and the technology has already attracted investments and partnerships fro around the globe.

International partners include Japan’s Kobe Steel, Ltd., Scientific Research Institute of Atomic Reactors and Rosatom, Russia.

These partners have aided the development of associated technologies such as clamps and irradiation measurement.

Travelling Wave Reactor (TWR)

• TerraPower is developing metallic nuclear fuel extrusions for its TWR reactor together with Idaho National Laboratory

(INL). These fuel extrusions are currently under testing in the advanced test reactor at INL.

• It has already manufactured the full sized test assembly of TWR by partnering with AREVA Federal Services.

Travelling Wave Sodium Cooled Fast Reactors

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• The fuel used in the IMSR is in liquid form, which improves the safety of operation of the reactor as there will no meltdown.

• The developed solution does not use pressurized component or water as the fuel itself acts as the coolant.

• Operates at atmospheric pressure unlike conventional reactors that operate at a pressure of 160 atmospheres of pressure.

• Much better fuel recycling is viable when compared to reactors using solid fissile material.

• No centralized fuel reprocessing is required to remove the fissile waste generated as IMSR enables continuous removal.

• IMSR is considered to be six times more efficient than conventional nuclear reactors, thanks to its ability to remove fissile

wastes continuously with minimal effort.

• IMSR is expected to operate at 700 degrees C providing heat for various industrial applications.

• The reactor requires low enriched uranium as it requires less enrichment than conventional reactors.

• The IMSR differentiates itself from the other molten salt reactors by using low or slightly enriched liquid uranium cycle

instead of thorium cycle.

• This reduces the proliferation risks associated with thorium cycle as it requires highly enriched uranium additives.

Integral Molten Salt Reactor

• Terrestrial Energy of Ontario, Canada, is involved in developing a safe and reliable integral molten salt reactor (IMSR).

• It has developed the reactor based on the first variant of the molten salt reactor where the fissile material itself is dissolved in a

molten fluoride salt and used to power the reactor.

• This is considered to be a safer nuclear technology than the contemporary ones using solid fuels.

Integral Molten Salt Reactor

Terrestrial Energy established a partnership with Oak Ridge National Laboratory (ORNL), USA, to take its reactor design to

the next stage. This collaboration is expected to help Terrestrial Energy to arrive at the parameters for concept and start

developing the engineering blueprint for the prototype. The blueprint is expected to be developed by the end of 2016.

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• The program sponsored and funded various collaborative efforts between universities, research entities, and industries to

develop safe, gas cooled reactors in the United States.

• The three main bodies involved are Idaho National Laboratory (INL), Department of Energy, and NGNP Industrial Alliance

• The main areas of the research focused are:

• Cost effectiveness

• Applicability

• Efficiency

• Safety and accident tolerance

• It was intended to develop a reactor with a thermal output capacity of 400 to 600 MW with a coolant output temperature of

850 to 900 degrees C.

• Other targets include production of hydrogen using the high temperatures.

• The fissile fuel and the fuel form for the VHTR is yet to be selected and the alliance expects to develop and operate an

prototype by 2021.

• The cost of the projects has been estimated to be around $4 billion.

Next Generation Nuclear Plant Program

• The Next Generation Nuclear Plant (NGNP) program is supported by the Office of Advanced Reactor Technologies (ART) of the

US DOE. This program aims at funding research and development of advanced generation IV reactor technologies.

• It was established to measure the technical and commercial viability of high temperature gas cooled reactors. These reactors can

supply electricity and high quality process heat for industries.

Facilitating Collaborations To Develop Very High Temperature Reactors

• In 2012, INL approved Areva prismatic steam-cycle high-temperature gas-cooled reactor (SC-HTGR) design as the optimal one for

the high temperature reactor prototype. This was chosen over the other two models, gas-turbine modular helium reactor (GT-MHR)

of General Atomics, USA and the conceptual configurations based on the pebble bed modular reactor (PBMR) submitted by

Westinghouse Electric Company LLC, USA.

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Kalimer-600

• It is based on KAERI’s sodium cooled fast reactor concept that was developed to meet the effective utilization of resources

and reduce nuclear waste.

• Currently, Waveguide sensor visualization technology is being developed by KAERI to analyze and inspect the interiors of

the reactor and the various sub-assemblies.

• It has been designed to have a electrical and thermal output of 600 MWe and approximately 1500 MWth respectively.

Very High Temperature Reactor

• The VHTR is considered as a source of thermal energy and hydrogen rather than as a source of electricity.

• The KAERI aims to achieve generation of hydrogen and industrial grade heat by attaining reactor temperatures of up to

900 degrees C.

• Other targets include development of high temperature corrosion resistant materials for reactors, refractory coated particle

fuel, and a thermochemical hydrogen generation technique.

Very High Temperature Reactors (VHTR)

• Korean Atomic Energy Research Institute (KAERI) of Korea, is developing two generation IV reactors—Kalimer600 and a very

high temperature reactor (VHTR).

• It is interested in developing nuclear power plants that meet these criteria; effective utilization of resources, minimization of waste

produced; reduced impact on environment; and improved competitiveness in terms of economics, safety, and reliability.

Nuclear Reactors for Heat and Hydrogen production

• KAERI has plans to start with the demonstration phase of the VHTR reactor by 2020 and commercialize the reactor by

2025.

• It plans to commercialize the advanced sodium cooled fast reactor by 2030.

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• The tubes holding the fuel salts are bundled together to form the fuel assemblies, which act as the reactor modules.

• The tank in which the assembly is placed is filled with the molten salt coolant.

• The molten salt coolant has the following characteristics:

• Not pressurized

• Does not react violently with air and water like the molten sodium coolant

• A secondary molten salt coolant arrangement is used to draw all the heat from the assembly to power generation.

• Coolant refueling is done by moving the fuel rod assembly out of the core and changing the molten salt coolant. This is

simpler than conventional methods.

• Further cooling of the reactor is enabled by natural flow of cold air.

• No high pressure systems are used making the construction cost effective and safer.

• Two models have been developed based on the type of fuel that can be used along with molten salt coolant.

Stable Salt Reactor

• Moletx Energy LLP of London has developed a reactor that is based on the second model of the molten salt reactors.

• The molten fuel salt mixture is held stable in vented tubes instead of being circulated.

• This technology has been patented globally and is expected to simplify the nuclear power generation process.

Non Circulating Molten Salt Reactor

The stable salt reactors are under construction and can be modeled to generate power from 150 to 1500 MWe. They can

be powered by low enriched uranium or by radioactive waste (such as actinides and plutonium) produced by conventional

reactors.

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ESNII

• ESNII has launched a number of projects in Europe including ASTRID and MYRRHA. One of the main goals of ESNII is

to complete and put these two projects into operational phase before 2025.

• ASTRID is a sodium fast reactor and MYRRHA is a flexible fast irradiation facility.

• Other programs of ESNII include

• Advanced Lead Fast Reactor European Demonstrator (ALFRED) a LFR demonstrator project to be constructed

by 2020. The National Agency for New Technologies, Energy and the Environment (ENEA) of Italy and Ansaldo

Nucleare of Italy and Nuclear Research Institute (Institutul de Cercetari Nucleare, ICN) of Romania are involved in

the construction of the ALFRED reactor.

ESNII+

• ESNII+ project was started in September 2013 and will be operational until September 2017.

• It is a preparatory phase project for supporting ESNII and preparing ESNII for the technical and economic challenges

for the period beyond 2020.

• ESNII+ will develop has 9 different work packages for guiding ESNII designed to strategically guide ESNII to complete the

research and development programs.

European Sustainable Nuclear Industrial Initiative

• The European Sustainable Nuclear Industrial Initiative (ESNII) was launched by the European Commission at the SET-Plan

Conference, Brussels, in 2010.

• The ESNII is considered to be one of the three main pillars of Sustainable Nuclear Energy Technology Platform (SNETP) of the

European Union.

Pillars of European Nuclear Research

ESNII aims at completing the Allegra and the MYRRHA projects first as they have been operational for long. ESNII will also

ably support SNETP to develop and complete similar nuclear research programs.

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The Road Ahead

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2018

Operation of scaled up Chinese HTR 10 plant.

Development of protypes of VHT reactors with

700 to 900 degrees C outlet temperature. 2020

Demonstration of molten salt and

sodium-based prototypes.

Development of conceptual designs

for Supercritical Water Cooled

Reactor

2025

2022

2028

Commercial scale up of molten salt

and sodium-based reactors.

Development of prototypes for the

VHTR with 1000 degrees C outlet

temperature. Realization of other generation IV

technologies and development of

prototypes.

Development of prototypes of

molten sodium- and molten

salt-based reactor.

The generation IV technologies are still in concenptual stage. Some reactors have reached pilot stage. The reoadmap describes what

evolution colud be expected and how long will it take to see the actual deployment of reactors. Based on the existing scenario it can be

evaluated that these demostrator plants based on these reactors can be expected between 2025 to 2030.

Technology Roadmap

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Appendix

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Key Patents

Patent Number Title Issue/Publication Date Applicants/Assignee

GB 2508537 A

A molten salt fission

reactor June 4, 2014 Scott Ian Richard

Abstract: A nuclear fission reactor is disclosed comprising a core, a pool of coolant liquid, and a heat exchanger 103. The core

comprises an array of hollow tubes 102 which contain molten salts of fissile isotopes, the tube array being at least partly immersed in the

tank of coolant liquid 101. The tube array comprises a critical region, where the density of the fissile isotopes during operation of the

reactor is sufficient to cause a self-sustaining fission reaction. Heat transfer from the molten salts of fissile isotopes to the exterior of the

tubes is achieved by any one or more of natural convection of the molten salts, mechanical stirring of the molten salts, boiling of the

molten salt, and oscillating fuel salt flow within the tubes. The molten salts of fissile isotopes are contained entirely within the tubes during

operation of the reactor.

US 2009/0252277 A1

Upper plenum structure

of cooled pressure

vessel for prismatic

very high temperature

reactor

October 8, 2009

Korea Atomic Energy Research

Institute

Korea Hydro & Nuclear Power

Co.

Abstract: An upper plenum structure of a cooled pressure vessel for a prismatic very high temperature reactor which secures a space for

coolant to supply to a core and also supports an upper reflector located inside a graphite structure on top of the core. The upper plenum

structure includes a cavity structure where the coolant goes down in the upper plenum structure, a plurality of upper reflector supports

formed with the cavity and supporting the upper reflector located on top thereof, and a plurality of coolant distributing blocks. Each of the

coolant distributing blocks is coupled with a bottom portion of a respective one of the upper reflector supports and is located on top of the

core in order to distribute the coolant collected in a cavity, formed by the upper reflector support, to the core. The coolant distributing

blocks cooperate with the upper reflector supports to define the cavity structure.

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Key Patents (continued)

Patent Number Title Issue/Publication Date Applicants/Assignee

WO 2015/094450 A9 Molten salt reactor October 22, 2015 Transatomic Power Corp

Abstract: A molten salt reactor includes: a fluoride fuel salt; and a metal hydride moderator.

WO 2015/038922 A1

Hybrid molten-salt

reactor with energetic

neutron source

March 19, 2015 Woolley Robert Daniel

Abstract: In an embodiment, a hybrid molten salt reactor includes a source of energetic neutrons, the energetic neutrons having a typical

energy per neutron of 14 MeV or greater, a critical molten salt reactor, and a molten salt comprising a dissolved mixture of fissile actinides

and fertile actinides. The molten salt circulates in a loop through the reactor vessel and around the source of energetic neutrons. The

fissile actinides and fertile actinides sustain an exothermic nuclear reaction in which the actinides are irradiated by the energetic neutrons,

the energetic neutrons inducing subcritical nuclear fission, and undergo critical nuclear fission when circulating through the critical molten

salt reactor. A portion of the daughter neutrons generated by nuclear reactions are captured by the fertile actinides in the molten salt and

induce transmutation of the fertile actinides into fissile actinides and sustain critical fission chain reactions in the molten salt reactor.

US 2011/0294083 A1 Molten salt treatment

system and process December 1, 2011 Tate & Lyle Technology Limited

Abstract

A molten salt treatment system and process can include one or more tubular conduits flowably connected to a molten salt reactor, the

tubular conduit containing concentrically within it a pipe or a shaft separated by an annular space therebetween, and one or more gas

sources connected to feed gas into the annular space. The system may include a scrubbing device flowably connected to a molten salt

reactor off-gas outlet to receive an off-gas, a first heating device configured to heat the effluent from the scrubbing device, and a filtering

device flowably connected to receive the effluent from the heating device. An overflow conduit may be flowably connected to a molten salt

reactor overflow outlet to receive molten salt therefrom and discharge the molten salt to a salt recovery vessel, and a blower or other gas

mover may be connected to the molten salt reactor and the recovery vessel to prevent backflow of cold gases through the overflow outlet

to the molten salt reactor.

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Key Patents (continued)

Title Patent Number Issue/Publication Date Applicants/Assignee

Reactor system with a lead-cooled fast

reactor WO 2015/115930 A1 August 6, 2015

KUBINTSEV, Boris Borisovich;

(RU).

Leonov, Viktor Nikolaevich; (Ru).

Lopatkin, Aleksandr Viktorovich;

(Ru).

Chernobrovkin, Yuriy Vasilievich;

(Ru)

Abstract : The invention relates to nuclear technology and is intended for use in power-generating systems with a fast reactor cooled by

a liquid-metal coolant which is primarily in the form of molten lead or an alloy thereof. The problem addressed by the invention consists in

reducing the specific volume of lead coolant per unit of power of the reactor and in increasing the safety of the reactor. The system

comprises a reactor cavity (1) with an upper cover (2), which is arranged in the reactor cavity (1) with an active zone (4), steam

generators (5), circulation pumps (7), circulation conduits (8) and (9), actuating mechanism systems and devices for starting up, operating

and shutting down the reactor system, wherein the steam generators (5) are in the form of tubular heat exchangers in which the lead

coolant (10) flows within pipes, while the water steam flows in a space between the pipes, the steam generators (5) are arranged in

separate boxes (6) and communicate with the reactor cavity (1) by means of circulation conduits for raising (8) and discharging (9) the

lead coolant (10), the steam generators (5) and a large portion of the circulation conduits (8) and (9) are arranged higher than the level of

the lead coolant (10) in the reactor cavity (1), and the circulation pumps (7) are arranged in the reactor cavity (1) on the circulation

conduits (8) and (9) for raising the "hot" lead coolant, and a technical means (13) is provided for ensuring intrinsic circulation of the lead

coolant (10) through the active zone (4) of the reactor when the circulation pumps (7) are switched off.

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Key Contacts

Leslie Dewan PhD, CEO, Transatomic Power, One Broadway, 14th Floor, Cambridge, MA 02142. E-mail:

ldewan@transatomicpower.com Phone: +1-617-470-3847. URL: http://www.transatomicpower.com/

Nicholas Touran, Reactor Physicist, TerraPower, LLC, 330 120th Ave NE, Suite 100, Bellevue, WA 98005. E-mail:

ntouran@terrapower.com. Phone: +1-425-324-2888. URL: http://terrapower.com/

David Hill PhD, Director, Terrestrial Energy Inc., 2275 Upper Middle Road East, Suite 102,Oakville, ON, L6H 0C3, Canada.

Phone: +1 (905) 766-3770 E-mail: dhill@TerrestrialEnergy.com URL: http://terrestrialenergy.com/

Timothy Abram, Professor in Nuclear Fuel Technology, Scientific Advisor, Moltex Energy LLP, 6th Floor, Remo House, 310-

312 Regent St., London W1B 3BS. Phone: +44 07730 052564 E-mail: tim.abram@manchester.ac.uk URL:

http://www.moltexenergy.com/