Molten Salt Reactors

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Many new next-generation reactors being designed are based on molten Fluoride and Chloride salts of Sodium, Lithium and other elements as coolants, and mediums in which fuels are dissolved. Some of these designs use Thorium rather than Uranium as fuel, and some are designed to burn existing used nuclear fuel (which still contains much of the theoretically burnable Uranium it started with) or Plutonium (such as now-surplus nuclear bomb material).

See also separate articles on:

Overview

Molten Salt Reactors Nick Touran

Molten Salt Reactors (MSRs) are nuclear reactors that use a fluid fuel in the form of very hot fluoride or chloride salt instead of the solid fuel used in most reactors. Since the fuel salt is liquid, it can be both the fuel (producing the heat) and the coolant (transporting the heat to the power plant). There are many different types of MSRs, but the most talked about one is definitely the Liquid Fluoride Thorium Reactor (LFTR). This MSR has Thorium and Uranium dissolved in a fluoride salt and can get planet-scale amounts of energy out of our natural resources of Thorium minerals, much like a fast breeder can get large amounts of energy out of our Uranium minerals. There are also fast breeder fluoride MSRs that don’t use Th at all. And there are chloride salt based fast MSRs that are usually studied as nuclear waste-burners due to their extraordinary amount of very fast neutrons.

BOOK ON MOLTEN SALT REACTORS Thomas J. Dolan (Nuclear, Plasma, and Radiological Engineering Department, University of Illinois, Urbana); Thorium Energy Conference 15

About 40 international authors are writing an 800 page book on Molten Salt Reactors. There are 25 chapters grouped in four main sections: Motivation, Technical Issues, Reactor Designs, and Global Activities and Issues. First drafts of most chapters have been received, and experts will review them this fall.
This book, written in cooperation with the International Thorium Molten-Salt Forum, will provide a comprehensive reference on the status of molten salt reactor (MSR) research as of 2015. MSRs could operate safely at atmospheric pressure and high temperature, yielding efficient electrical power generation, desalination, actinide incineration, hydrogen production, and other industrial heat applications. In some versions on-line fuel processing could adjust the fuel composition continuously. The book should be useful for nuclear researchers, industrial engineers, university faculty and students, and and leaders of industry and government who want to understand the advantages of this promising energy source. Many chapters will involve collaboration of several authors.
The schedule is to have most draft chapters by the end of September, 2015; to review and improve them in October-December; and to publish the book in 2016. This book should raise awareness of MSR research as an important field, worthy of public and industrial support. Experts from India and other countries will be welcome to review chapters and to suggest improvements.

MSFR - Bibliography Laboratory of Subatomic Physics & Cosmology, IN2P3 (CNRS), Université Grenoble Alpes

Bibliography of work on Molten Salt Fast Reactors

2017 PLATTS NUCLEAR ENERGY CONFERENCE Kirk Sorensen; Energy from Thorium; 13 Feb 2017

I was asked to speak at the Platts Nuclear Energy Conference in Washington, DC, on February 10, as part of their panel on “New Approaches to Advanced Reactor Design.”
discusses waste management, and presents graphic illustrating differences in neutron spectrum and fuel types of molten salt reactors current being proposed/developed

http://scienceforsustainability.org/pix/energy/nuclear/msr-design-space-graph.jpg

Oak Ridge National Labs - Molten Salt Reactor Experiment

MSRE: Alvin Weinberg's Molten Salt Reactor Experiment "Th" Thorium Documentary; 30 Mar 2016

Oak Ridge National Laboratory was the home of Alvin Weinberg's Molten Salt Reactor Experiment. The MSRE proved that a fission reaction in molten fluoride salts could be contained in Hastelloy-N, and that a molten salt fueled reactor concept was viable. Two prototype molten salt reactors were successfully designed, constructed and operated at ORNL. The Aircraft Reactor Experiment in 1954 and Molten-Salt Reactor Experiment 1965-1969. Both used liquid fluoride fuel salts. The MSRE demonstrated fueling with U-233 and U-235. Alvin Weinberg was removed from his post and the MSR program closed down in the early 1970s. Aircraft Reactor Experiment & Molten Salt Reactor Experiment remain the only molten salt reactors ever operated.
mixes historic footage of the MSRE with video of Kirk Sorensen, Briony Worthington etc visiting ORNL and talking to engineers involved with the early work

ORNL MSRE film

The Molten-Salt Reactor Experiment Oak Ridge National Laboratory; YouTube; 14 Oct 2016

This film was produced in 1969 by Oak Ridge National Laboratory for the United States Atomic Energy Commission to inform the public regarding the history, technology, and milestones of the Molten Salt Reactor Experiment (MSRE). Oak Ridge National Laboratory's Molten Salt Reactor Experiment was designed to assess the viability of liquid fuel reactor technologies for use in commercial power generation. It operated from January 1965 through December 1969, logging more than 13,000 hours at full power during its four-year run. The MSRE was designated a nuclear historic landmark in 1994.

CLASSIC ORNL MSRE FILM KIRK SORENSEN; Energy from Thorium; 16 Oct 2016

Transcript of film

Robert Hargraves - The Energy Collective

Energy Cost Innovation, Part 1: Liquid Fuel Nuclear Reactors Robert Hargraves; The Energy Collective; 26 Aug 2013

Overview of reactor technologies especially aqueous and molten salt types, Aircraft Reactor, Thorium, MSR vs LMFBR, politics etc

Energy Cost Innovation, Part 2 Robert Hargraves; The Energy Collective; 27 Aug 2013

costs and features

Energy Cost Innovation, Part 3: Global Impact of Low-Cost Clean Energy Robert Hargraves; The Energy Collective; 28 Aug 2013

value of energy to deelopment, global warming, synthetic fuels, EROI, MSR development

EPD (Energy Process Developments) study

Feasibility of Developing a Pilot Scale Molten Salt Reactor in the UK

Six different reactor options were assessed in the MSR review:

  • Flibe Energy’s Liquid Fluoride Thorium Reactor (LFTR),
  • Martingale’s ThorCon,
  • Moltex Energy’s Stable Salt Reactor
  • Seaborg Technologies – Seaborg Waste Burner
  • Terrestrial Energy’s Integral MSR
  • Transatomic Power Reactor

The Weinberg Foundation's article: A Comprehensive Molten Salt Reactor Review has some well-informed discussion in the comments.


6 Nuclear Energy Companies Building Molten Salt Reactors

  • Terrestrial Energy
  • Moltex
  • ThorCon
  • Terrapower
  • Flibe Energy
  • Transatomic Power

MOLTEN SALT REACTORS - SAFETY OPTIONS GALORE Charles Barton / Nuclear Green Revolution

post of paper by Uri Gat of Oak Ridge National Laboratory & H. L. Dodds of University of Tennessee at Knoxville

Europe’s expertise in nuclear science and engineering will take thorium technology forward, John Laurie Copenhagen Atomics blog

This is part 2 of our conversation with John Laurie, author of the biggest blog on thorium energy in France.
Thorium, MSR

Charles Barton's commentaries

The Big Lots Reactor Revisited Charles Barton; Nuclear Green Revolution; 30 Jul 2010

Barton suggests building cheaper molten salt reactors using cheaper but less durable steel materials, but compensating for their reduced power*lifetime factors by operating in variable, load following, power cycles

What Are The Problems With LFTR Technology? Charles Barton; The Energy Collective; 29 Aug 2011

What are the problems with MSR/LFTR technology? This turns out to be a hard question to answer. Since there are a large number of LFTR design options, however, it is difficult to identify a set of problems that shared all of the options. Rather we should talk about elective choices, and the problems that a MSR/LFTR designer would face if a certain option were chosen.
  • 23 Apr 2016
I have reached the point at which I an conceive of future Nuclear Green Posts, I lack the where with all to do the research and generte written text. There are still important topics that no one is writing about. And unless the solid moderator problem is solved, we need to consider the possibility of FLiBe moderated epithermal MSRs. The choice of FLiBe will have some interesting consequences. It will limut the amount of of Plutonium that rhe Carrier/coolant/moderator salt can can carry. It will also lead to the production of a large amount of Tritium, which will have to be removed from core salts. The epithermal FLiBe moderated MSR Would seem to work best as a LFT, but it is not clear to me if it would work best as a burner or as a breeder. This would probably be a question for Mark Massie, or David LeBlanc to look at in their free time.
Another question would be alternative means of U-233 production. Those means would include thorium breeders as well thoriumtarget in a proton spilator. A floride carrier salt (again quite possibly FLiBe) could be used to carrie thorium in a blanket of a fusion reactor. As my father long ago suggested FLiBe could be used to capture heat from neutrons produced by thefusion process, and with aq FLiBe blanket, carrying thorium is a doable proposition. Just ask Ralph Moir. Thus by adding a molten salt blanket fussion can lead to heat capture as well as U-233 breeding. This makes fusion quite a bargan.
There are still stories to be told about molten salts with or without thorium.
  • unknown date
What are the disadvantages of the TAP reactor? The TAP Reactor is a medium size reactor. Unfortunately the Current concept, requires considerable field construction as opposed to factory construction. One of the major advantages of small modular reactors is that more construction can be expected to take place in factories. It is highly desirable that the entire project can be shipped to the field by truck, rail or barge, and assembled in a relatively short period of time. The reactor and its attendant facilities can be housed in prefabricated structures, that can be quickly assembled. If these structures are assymbled underground, they do not have to be massive, since rock and or soil will protect the reactor cor from attacks by aircraft or high explosives. Factpory construction of major parts in a small reactor can be accomplished through far more efficient use of lower cost labor than would be possible in a field construction environment. Thus it is highly desirable to limit feield labor as much as possible. It is notr clear what would be the optimal size for alow cost and quickly assembyles MSR, but the 3 year construction time suggested for the TAP reactor would far too long.
It might be that the 500 MWe size of the TAP reactor is an optimal size for the fuel efficiency that TAP desires. If so, it might be worth while for TAP to devote the same ingenuous attention to the manufacture of the TAP reactor, as they have devoted to their core design. The goal of increasing manufacturing efficiency is every bit as desirable as improving the efficiency of the nuclear process is.
  • 24 Mar 2016
I have noted before that there is considerable controversy related to the Transatomic Power's plan to use Zirconium hydride alloy as a MSR moderator. The hope is that Zirconium hydride will prove a more satisfactory moderator than Graphite. Under radiation, Graphite shrinks and then swells. Unfortunately the geometric changes make graphite an unsatisfactory moderator as it ages. Zirconium hydride was originally intended to serve as a moderator that was launched into space. Later it was used in reactorsa that were designed for student use. In that role, Zirconium hydride has proven satisfactory. Massie and Dewan believe that Zirconium Hydride, together with appropriate cladding, will prove a satisfactory moderator for a Middle size Molten Salt Reactor. Yet their life expectancy of the Zirconium hydride moderator is from 4 years to an almost indefinate period. A 4 year moderator life span would be very unsatisfactory, and might jepordize the TAP Reactor marketability. In addition, other MSR advocates have raised questions about the stability of the TAP reactor core. The latest TAP Technical White Paper includes a discussion of Zarconium-hydride moderator.
What are the disadvantages of the TAP reactor? The TAP Reactor is a medium size reactor. Unfortunately the Current concept, requires considerable field construction as opposed to factory construction. One of the major advantages of small modular reactors is that more construction can be expected to take place in factories. It is highly desirable that the entire project can be shipped to the field by truck, rail or barge, and assembled in a relatively short period of time. The reactor and its attendant facilities can be housed in prefabricated structures, that can be quickly assembled. If these structures are assymbled underground, they do not have to be massive, since rock and or soil will protect the reactor cor from attacks by aircraft or high explosives. Factpory construction of major parts in a small reactor can be accomplished through far more efficient use of lower cost labor than would be possible in a field construction environment. Thus it is highly desirable to limit feield labor as much as possible. It is notr clear what would be the optimal size for alow cost and quickly assembyles MSR, but the 3 year construction time suggested for the TAP reactor would far too long.
It might be that the 500 MWe size of the TAP reactor is an optimal size for the fuel efficiency that TAP desires. If so, it might be worth while for TAP to devote the same ingenuous attention to the manufacture of the TAP reactor, as they have devoted to their core design. The goal of increasing manufacturing efficiency is every bit as desirable as improving the efficiency of the nuclear process is.
Every month or two, I look at the Transatomic Power Internet page to see what TAP is doing and saying. My latest exploration has revealed a revised White Paper dated January 2016. This document is well worth exploring. Clearly TAP has been looking carefully at its design, and the latest statemebnts yield some interesting insights into their progress. First, They now seem very confident in their Zarconium Hydride moderator, which the white Paper states will occupie less space than a Graphite moderator would require.
If the TAP reactor can fulfill the clames being made with increasing confidence by the latest TAP White Paper, it could very well prove to be a revolutionary reactor design, even by the already revolutionary standards of Molten Salt Reactors. Look for the DOWNLOAD OUR WHITEPAPER button on the TAP page.

French CNRS Molten Salt Fast Reactor

Molten Salt Reactor

The concept of Molten Salt Fast Reactor (MSFR): Molten Salt Reactor with a Fast Neutron Spectrum operated in the Thorium fuel cycle
The CNRS has been involved in molten salt reactors since 1997. Starting from the Molten Salt Breeder Reactor project of Oak-Ridge, an innovative concept called Molten Salt Fast Reactor or MSFR has been proposed, resulting from extensive parametric studies in which various core arrangements, reprocessing performances and salt compositions were investigated to adapt the reactor in the framework of the deployment of a thorium based reactor fleet on a worldwide scale (see next paragraph below). The primary feature of the MSFR concept is the removal of the graphite moderator from the core (graphite-free core), resulting in a breeder reactor with a fast neutron spectrum and operated in the Thorium fuel cycle. MSFR has been recognized as a long term alternative to solid fuelled fast neutron systems with unique potential (negative safety coefficients, smaller fissile inventory, easy in-service inspection, simplified fuel cycle…) and has thus been selected for further studies by the Generation IV International Forum in 2008.
In the MSFR, the liquid fuel processing is part of the reactor where a small side stream of the molten salt is processed for fission product removal and then returned to the reactor. This is fundamentally different from a solid fuel reactor where separate facilities produce the solid fuel and process the Spent Nuclear Fuel. Because of this design characteristic, the MSFR can thus operate with widely varying fuel composition. Thanks to this fuel composition flexibility, the MSFR concept may use as initial fissile load, 233U or enriched (between 5% and 30%) uranium or also the transuranic elements currently produced by PWRs in the world.

Terrapower molten Chloride reactor

A Bill Gates-backed energy company is developing what could be a game-changing nuclear reactor Peter Kotecki; Business Insider; 27 Nov 2018

TerraPower, an energy company cofounded by Bill Gates, builds advanced nuclear reactors. The company is developing a new reactor that uses molten chloride instead of water as a coolant. TerraPower believes the design will be safer and more efficient than today's reactors.

Molten Chloride Fast Reactor

Southern Company Awarded Up To $40M From DOE

Fast Reactors Using Molten Chloride Salts as Fuel M. Taube; Swiss Federal Institute for Reactor Research; Jan 1978

Report dealing with "a rather exotic "paper reactor" in which the fuel is in the form of molten chlorides" in four different (though all fast breeder) configurations.

Sherrell Greene on Liquid Chloride Reactors, "Business as Usual," and a second Manhattan Project Charles Barton; Nuclear Green Revolution; 19 Nov 2011

The third part of my interview Q&A with Sherrell Green focused on questions concerning the future of nuclear technology. My father had been a pioneer in research on Liquid Chloride Reactor technology in the 1950's. Sherrell Greene mention LCR development during out preinterview, so I wanted to ask him some follow up questions. The LCR is a potential competitor to the Liquid Metal Fast Breeder Reactor, but it is not clear if itsadvantages would out wight its potential costs.

Elysium

Elysium Industries website

Molten Chloride Salt Fast Reactor
Thermal Capacity: 110 - 2700 MWth (Flexible)
Electrical Capacity: 50 - 1200 MWe (Flexible)
CONSUMES NUCLEAR WASTE
Elysium's design is a fast-spectrum reactor meaning the majority of fissions are caused by high-energy (fast) neutrons. This enables conversion of fertile isotopes into energy-producing fuel, efficiently using nuclear fuel, and closing the fuel cycle. In addition, this can enable the reactor to be fueled with spent nuclear fuel from water reactors. The Elysium MCSFR closes both the water reactor and its own fuel cycle.
REDUCE STOCKPILES
Plutonium from weapons stockpiles and spent fuel separations currently presents a proliferation concern worldwide. Elysium's fuel salt chemistry lends itself to incorporation of weapons-grade or reactor-grade plutonium, which provides a path to stockpile reduction. Since no actinides are removed from the reactor, the Elysium fuel cycle is not a proliferation concern.
SECURE FACILITY
Facility design minimizes external threats, and the reactor is below grade. In addition, since the reactor does not produce spent fuel actinide waste, the security risk of storing spent fuel onsite (as with conventional nuclear reactors) is eliminated. Once added to the reactor, actinides are never intentionally removed from the reactor compartment, which is sealed and monitored.

TC No 29 Ed Pheil • Molten Chloride Salt Fast Reactor Kieth Rodan; YouTube; 7 Jan 2020

ED PHEIL Chief Technology Officer and Co-Founder of Elysium Industries presents his company's design for a Molten Salt Chloride Fast Reactor. (Thorium Energy Alliance Conference TEAC-8, St. Louis, MO, 2017)

DFR / dual fuel reactor

Dual Fluid Reactor schematic.jpg

The Dual Fuel reactor uses molten salt as its fuel solvent and primary heat transfer medium, in a configuration with freeze plugs for safety derived from the ORNL MSRE. A second heat transfer loop using molten lead as coolant transfers heat to raise steam to drive turbines.

The DFR claims to operate at 1000 °C, giving a thermal efficiency of 60%.

It claims to be able to burn up spent fuel from conventional once-through reactors.

Dual Fluid reactor website

"The Dual Fluid Reactor - A novel concept for a fast nuclear reactor of high efficiency" by Armin Hukea, Gotz Ruprecht, Daniel Weißbacha, Stephan Gottlieb, Ahmed Husseina, Konrad Czerski in Annals of nuclear energy (preprint), 19 Feb 2015 local copy.

"The Dual Fluid Reactor" - slides from presentation at Thorium Energy conference October 2018, Thorium Energy World | local copy

A dissertation, "Analysis and Evaluation of the Dual Fuel Reactor concept", by Xiang Wang submitted to the Technical University of Munich discusses and analyses the DFR design; TUB | local copy

LFTR: Liquid Fluoride Thorium Reactor

LFTR: A Long-Term Energy Solution? (Victor Stenger; HuffPo; 1 Sep 2012)

Seaborg Wasteburner

Advances in Small Modular Reactor Technology Developments IAEA 2016

The Seaborg Technologies’ Molten Salt Thermal Wasteburner (MSTW) is a concept with a single molten fuel-salt to be operated on a combination of spent nuclear fuel and thorium. The design efforts are currently focused on advanced multi-physics, neutronics, and early engineering details.

Seaborg Technologies website

Seaborg Wasteburner Molten Salt Reactor whitepaper (via Internet Archive)

Making Safe Nuclear Power from Thorium Thomas Jam Pedersen; TEDxCopenhagen; 15 Nov 2016

Thomas Jam Pedersen, engineer and co-founder of Copenhagen Atomics, was skeptical at first upon discovering and reading about thorium energy, which is present everywhere in the world and could technically provide an inexpensive energy supply for everyone for thousand years.
While the world is still heavily relying on fossil fuels, thorium energy and nuclear reactors, which reuse nuclear waste, are now part of the energy debate, proposing a pollution-free solution that could provide an unlimited supply of fuel for the next millennium.
Thomas Jam Pedersen aims to build a thorium molten salt reactor in Copenhagen, and introduce thorium energy to the public eye.
Thomas Jam Pedersen is an engineer, who has extensive experience in software and simulations. With a group of chemical engineers and physicists, he co-founded the startup Copenhagen Atomics. He also writes a blog about thorium energy on the website Ingeniøren.

Seaborg 100 MWe Molten Salt Reactor would fit on a regular truck and burn nuclear waste Brian Wang; Next Big Future; 3 Aug 2018

Seaborg is the largest reactor design start-up in Europe. They have a design for a molten salt reactor that is ten times smaller than the Terrestrial Energy IMSR. It would 20 to 30 times smaller than an existing pressure water nuclear reactor for submarines.
Seaborg CUBE reactor can use spent nuclear fuel (SNF) by adding thorium as a catalyst. The CUBE as a waste burner. Current conventional reactors use about 4% of the uranium fuel rods. This is because they use Uranium 235 and cannot use the Uranium 238.
250 MW Thermal for 100 MW of electricity,
The fits it a half-length 20 foot shipping container
35 ton MSR Game changer in SMR-MSR size:
cuboid of 2.4 meters by 2.4 meters x 6 meters, and 30 tons Development
Timeline aligned with standard IAEA reactor development method
  • 2014-2016: Pre-conceptual Design Phase 1
  • 2017-2018: Pre-conceptual Design Phase 2; 1.5 Million Euros
  • 2019-2020: Conceptual Design Phase; 10 Million Euros
  • 2021-2024 Technical Design Phase; 50 Million Euros
  • Ready to build reactor blueprints
Delivered cost for 250 MW thermal MSR in 2025 in the $50 Million to $70 Million depending upon manufacturing scale. They are working towards a 50 MW thermal pilot plant and then would scale to 250 MW thermal for a commercial system.

South Korea deal

Danish nuclear entrepreneurs land giant deal in South Korea: 'We chase three-digit million amount' Anders Leonhard; Finans; Dec 2019?

The unique technology has attracted so much attention in Asia, in particular, that Seaborg has now landed a huge deal with a major South Korean energy company whose name is not yet public.
The agreement is a partnership where Seaborg and the South Koreans will build 7,500 of Seaborg's nuclear reactors in Southeast Asia until 2040.
Seaborg expects to have their first reactor running in 2024, if all goes according to plan. But before it is ready, according to Troels Schönfeldt, 300 million have been spent. euro - equivalent to approx. 2.25 billion kr.
"Half will go to development, and the second half will produce the first reactor, which is much more expensive than the next," he says.
Seaborg currently has 28 employees, but the goal is to create a new Danish export success - especially to Southeast Asia, where the climatic conditions mean that solar, wind and water energy do not have optimal conditions.

Transmutation / waste burning

MOLTEN SALT REACTORS FOR BURNING DISMANTLED WEAPONS FUEL URI GAT and J. R., ENGEL Oak Ridge National Laboratory, H. L. DODDS University of Tennessee / Nuclear Engineering Department; 28 May 1992

The molten salt reactor (MSR) option for burning fissile fuel from dismantled weapons is examined. It is concluded that MSRS are potentially suitable for beneficial utilization of the dismantled fuel. The MSRs have the flexibilify to utilize any fissile fuel in continuous operation with no special modifications, as demonstrated in the Molten Salt Reactor Experiment, while maintaining their economy, The MSRS further require a minimum of special fuel preparation and can tolerate denaturing and dilution of the fuel. Fuel Shipments can be arbitrarily small, which may reduce the risk of diversion. The MSRS have inherent safety features that make them acceptable and attractive. They can burn a fuel type completely and convert it to other fuels. The MSRs also have the potential for burning the actinides and delivering the waste in an optimal form, thus contributing to the solution of one of the major remaining problems for deployment of nuclear power.

TRANSMUTATION CAPABILITY OF ONCE-THROUGH CRITICAL OR SUB-CRITICAL MOLTEN-SALT REACTORS Elena Rodriguez-Vieitez, Micah D Lowenthal, Ehud Greenspan, Joonhong Ahn; Conference: “Actinide and Fission Product Partitioning and Transmutation”; 2002

A neutronic parametric study is performed for graphite-moderated molten-salt (MS) critical or source-driven sub-critical transmuting reactors. The NaF-ZrF 4 MS reactor is fuelled with transuranium isotopes from LWR spent fuel and operates in a once-through mode. The MS with actinides is continuously fed and continuously extracted at a very slow rate. All the fission products are removed from the core as soon as formed. The primary question addressed is whether or not it is possible to design such a reactor to have an acceptable k eff when at equilibrium composition, while the Ac concentration is below their solubility limit, and what is the corresponding transmutation fraction. The primary design variables are the MS channel diameter and the graphite-to-MS volume ratio (C/MS). For an average power density of 390 W/cm 3 of MS, MS feed rate of 1 millilitre/day/MW th and actinide concentration of 12.87 mol% it was found that both k eff and the fractional transmutation peak while the equilibrium concentration is at a minimum when C/MS is close to 1.0. The equilibrium actinide concentration is below the solubility limit for C/MS between 1 and 7 for 7cm and 3.5 cm channel diameter and between 1 and 15 for a 1 cm channel diameter. The peak k eff is close to 1.0 and the fractional transmutation exceeds 90% in one pass through the core. The Pu coming out from the C/MS=12 core has a very low fissile content of only 17%. The optimal core has an epithermal spectrum and small channel diameter. The graphite lifetime in the core is 0.6 or 1.3 years for C/MS of 1 or 3, respectively. Reduction of the power density to 39 W/cm 3 can increase the graphite lifetime by an order of magnitude. This reduction of the power density reduces the attainable k eff by ~5% and increases the equilibrium actinide concentration by ~0.4 mol%. An illustrative core design for a 10 GW th MS transmuter is given.

Chinese Academy of Sciences

China spending US$3.3 billion on molten salt nuclear reactors for faster aircraft carriers and in flying drones Brian Wang; Next Big Future; 6 Dec 2017

China will spend 22 billion yuan (US$3.3 billion) on two prototype molten salt nuclear reactors.
Two molten salt nuclear reactors will be built in the Gobi Desert in northern China.
  • Molten salt reactors can produce one thousandth of the radioactive waste of existing nuclear reactors because of deep burn. More complete conversion of the nuclear fuel.
  • Molten salt reactors can have designs that are proof against nuclear meltdowns
  • The chinese reactors could use thorium. China has some of the world’s largest reserves of the thorium metal.
The Chinese project has been funded by the central government and the two reactors are to be built at Wuwei in Gansu province, according to a statement on the website of the Chinese Academy of Sciences. The lead scientist on the project is Jiang Mianheng – the son of the former Chinese president Jiang Zemin – and it is hoped the reactors will be up and running by 2020.