Molten Salt Reactors

13th GIF-IAEA Interface Meeting IAEA Headquarters, Vienna. 18-19 March 2019

GIF MSR systemDevelopment Status of Presented by Victor Ignatiev, RF

Status of MSR development 1 Different Reactor Concepts using Molten Salt are Discussed at GIF MSR pSSC Meetings • Within the GIF, research is performed on the MSR concepts, under the MOU signed by Australia, Euratom, France, Russian Federation, Switzerland and USA. • China, Canada, Korea, and Japan contribute as observers • Two fast spectrum MSR concepts are being studied, large power units based on homogeneous core with liquid fluoride-salt circulating fuel: MSFR design in France, Euratom and Switzerland as well as MOSART concept in the Russian Federation. R&D studies are on-going in order to verify that fast spectrum MSR systems satisfy the goals of Gen-IV reactors in terms of sustainability, non-proliferation, safety and waste management • The US is focused on liquid fueled MCFR (Molten Chloride salt Fast Reactor) as well as some other solid (FHR) and liquid fuel fluoride based designs • China and Canada, as observer in the pSSC of the MSR, are working on thorium - uranium liquid fuel fluoride salt designs, respectively TMSR and IMSR • 27rd GIF MSR pSSC meeting, was held at ANSTO (Australia) in March 2019

Status of MSR development 2 Status of expressions of interest

rd pSSC Members Observers 27 GIF MSR pSSC meeting, ANSTO Canadian 10-15 March 2019 Consortium • Tuesday Australia Euratom France Russia US Switzerland China Japan Korea • Wednesday TEI CNL • Thursday RSWG Workshop • Friday ANSTO Technical Tour L. Edwards Materials X X X X X

Salt O. Bennes X X X X X X X properties System J. Krepel X X X X X X X X Integration  Most of the MSR pSSC members and observers have expressed their interest in the different PAs.  Interest among PAs is quite “balanced”  Observers should also join the SA Collaborations: Europe • Institutional projects with Direct funding - Gen IV policy support to EU commitments - Member states support • EU HORIZON2020 project (Indirect funds) - SAMOFAR project (ends 08/2018) - SAMOSAFER from 1/10/2019 (4 year project granted by EU) • Collaboration agreements with Member States - Netherlands – TUD, NRG (SALIENT01 irradiation - ~3M€) - Fuel preparation of SALIENT03 irradiation (followed by PIE) - Italy, Czech Rep., France, Slovakia • Collaboration agreements with International partners - US (I-NERI) - CNSC - Terrestrial Energy (Q-A work) MSR Activities at JRC • Synthesis of An-fluoride salts

• Physico-chemical properties investigation

• Thermodynamic Database of F- salts

• Pyrochemical reprocessing of the fuel salt

• PIE of fuels

Status of MSR development 8 Czech activities in 2018 – 2019 • The main activities in the period from last pSSC MSR meeting to present days were focused on the preparation of the future measurement of the FLIBE neutronic parameters at the temperature range between 500 °C to 750 °C. • To realize these measurement at LR-0 experimental reactor, the new inserted zone with hot liquid FLIBE salt was calculated, predesigned and is now ready for manufacture. The new zone will be significantly bigger than the previous zone used for the measurement at room temperature. The zone will be preheated outside the reactor, then placed into insulation case and finally put into the reactor for measurement. • The other activities related to the development of Czech MSR program continued in agreement with the Czech national project on MSR technology development. These activities cover the FLIBE loop program (change of gaskets in loop flanges, preparation of the ŠKODA pump for the installation in the loop etc.), blade design optimizations of the ŠKODA impeller, continuation of the electrochemical studies of An/FP separation from fluoride salts and continuation of the long-term MONICR corrosion experiments in FLIBE. • Moreover, in the frame of collaboration between the Research Centre Řež and NRG Petten related to the irradiation experiments, both the MONICR samples for irradiation and the capsules of FLIBE salt with UF4 and ThF4 were prepared in Řež and now they are ready for shipment to Petten. Irradiation tests NRG Petten

• SALIENT-01: • Gamma irradiation of fresh salt • 78LiF-22ThF4 in graphite crucibles samples • 12 out of 18 cycles completed (end of irradiation: September 2019) (LiF, BeF2, UF4, ThF4, 71.7LiF-16BeF2- • Preparations for post-irradiation examination are underway: 12.3UF4) • Gamma spectrometry • Radiolytic gas production: • Fission gas release by puncturing / mass spectrometry • SEM/WDS: Noble metal particle size, salt-graphite interaction, pressure vs. dose FP diffusion and vaporization-condensation • Sample synthesis and fabrication finished at research Center Rez • Start of irradiation scheduled Q3 2019

• SALIENT-03: • Design completed:

• 75LiF-18.7ThF4-6UFx-0.3PuF3 in welded Hastelloy N / GH3535 capsules • Electric heaters, to avoid radiolysis • In-pile monitoring of pressure and redox potential • Projected start of irradiation: Q4 2019 Progress in Italy

500W No fan

500W No fan 2018 Collaborations in Russia • Institutional projects with Direct funding - Gen IV policy support to RF commitments

• 2018 Rosatom MSR related Awards: KI, VNIITF, VNIINM, MCC, OKBM, NIKIET 1. R&D needs for closure of the nuclear fuel cycle for all actinides with MSR at MCC site 2. Development of the methods for actinides fluorides production as applied to MSR 3. Conceptual development of the fast U-Pu MSR

• Collaboration agreements with International partners - EU (SAMOFAR - KI) - SINAP (China) 1. Key physical & chemical properties for different coolant compositions; 2. Combined materials compatibility & salt chemistry control; 3. Development and experiments with component molten salt test facilities 2018 DOE-NE Industry Awards • Modeling and Optimization of Flow and Heat Transfer in Reactor Components for Molten Chloride Salt Fast Reactor Application • Elysium Industries USA - $3,200,000 • Fluorination of Lithium Fluoride-Beryllium Fluoride Molten Salt Processing • Flibe Energy & PNNL - $2,627,482 • in situ Measurement and Validation of Uranium Molten Salt Properties at Operationally Relevant Temperatures • University of Connecticut (CFA-18-15065) - $799,979 • Development of an MC&A toolbox for liquid- fueled molten salt reactors with online reprocessing • University of Tennessee (CFA-18-15061) - $799,207 • Determination of Molecular Structure and Dynamics of Molten Salts by Advanced Neutron and X-ray Scattering Measurements and Computer Modeling • MIT (CFA-18-15093)- $800,000 • Corrosion Testing of New Alloys and Accompanying On-Line Redox Measurements in ORNL FLiNaK and FLiBe Molten Salt Flow Loops • Georgia Institute of Technology (CFA-18-14977) - $800,000 10 UNF infrastructure in Russia Facilities of Test Demonstration Centre being built at the site of the Mining and Chemical Combine after 2020 will start reprocessing of UNF from VVER-1000, providing a recovered fissile materials for recycling in thermal and fast reactors. TDC will become the reference basis for the large-scale RT-2 plant, which will provide an environmentally and economically acceptable system of VVER-1000/1200 UNF recycling both in Russia and abroad.

VVER-1000 UNF – since 2016 UNF Centralized wet and dry storage facilities PuO2

Test Demonstration Centre for UNF reprocessing (commissioning in 2021)

Underground research Partitioning and laboratory isotopes production (commissioning in 2024 ) Modernization of the HLW management infrastructure BN-800 MOX-fuel fabrication

In accordance with today TDC flowsheet, the HLW, containing Am and Cm is the subject for vitrification Introduction of MOSART into nuclear power help to solve the problem of long-lived actinides

Fuel salt, mole% LiF-BeF +1TRUF Used fuel Reprocessing Waste conditioning 2 3 Temperature, оС 620-720

ILW Core radius/height, m 1.4/2.8 VVER disposal ILW Core specific power, W/cm3 130 Container material HN80MTY alloy

Fresh fuel U, Pu TRU Removal time for soluble FP, yr 1-3 Solvent, Feed Loading TRU/MA, Enrichment MSR mole % MA/TRU (EOL), t kg/yr & fabrication 73LiF-27BeF2 0.1 3.9 730/73

Uranium 73LiF-27BeF2 0.35 13.9 730/260 Production 73LiF-27BeF2 0.45 23.2 730/330 12 R&D work packages

1. Development of container material for fuel and intermediate circuit 2. Development of flowsheets for the preparation and processing of fuel salt 3. Development of structural materials for the fuel salt processing unit 4. Conducting physico-chemical studies 5. Development of analytical methods for monitoring the fuel salt and intermediate coolant 6. Justification of reactor safety 7. Development of technologies for auxiliary components and systems 8. Ensuring maintainability and organization of equipment maintenance 9. Development of control and measuring systems 10. Creation of an electrically heated mock up 11. Design development for the 10-50 MWt experimental reactor 12. Design development for a 2.4 GWt MOSART The construction of a large power MOSART is proposed to be preceded by the construction of 10 MWt test MOSART unit to demonstrate the control of the reactor and fuel salt management with its volatile and fission products with different TRU loadings for start up, transition to equilibrium, drain-out, shut down etc.

2019

Program plan for 2020 R&D needs Pre-conceptual Experimental 2025 studies of the infrastructure reactor plant and (radiation damage 2028 processing unit must tests and integral Design be performed to forced convection documentation of establish the MSR Development of salt loops) are the 10 MWt MSR 2033 viability (reactor and technologies and required to proceed for burning TRU’s fuel salt clean-up further in the from SNF at the equipment for unit to be optimized Test 10 MWt MOSART-E. mastering of fuel / MCC site transmutation of together) coolant salts and radwaste at the Full - scale MOSART materials technology experimental detailed design infrastructure

There are opportunities to further improve the efficiency of minor actinides burning in MOSART, which will be justified by the results of the experimental setup

14 MSR related papers’ 2018-2019

• Corrosion Resistance and Mechanical Stability of Nickel Alloys in Molten-Salt Nuclear Reactors, Atomic Energy, 124, 1, pp 43-49, 2018 • Accidental resistance of molten salt reactor, Atomic Energy, 124, 6, pp 371-378, 2018 • Molten salt reactor as the necessary element for the closure of the nuclear fuel cycle for all actinides, Atomic Energy, 125, 5. pp 251-255, 2018

• Measurement of the kinematic viscosity for the molten 73LiF-27BeF2 salt mixture and effect on its the viscosity of cerium trifluoride and zirconium tetrafluoride additives, Atomic Energy, 125, 2, pp 91-94, 2018 • Analysis of the fuel circuit characteristics for the molten salt reactor with homogeneous core, Atomic Energy, 126, 2019 • Effects of silicon carbide on the corrosion of metallic materials in molten LiF-NaF-KF salt, Corrosion Science, 143, pp 157-165, 2018 • Effect of exposing duration on the interaction between nickel-based alloy and SiC in molten LiF-NaF-KF salt, J. of NUCLEAR MATERIALS, 515, pp. 276-283, 2019

• Voltammetric measurements on the [U(IV)]/[U(III)] couple and embrittlement of high nickel alloys in fuel LiF-BeF2- UF4 salt with tellurium addition in application to molten salt reactor, Corrosion Science, 2019 • Neutronic benchmark of the molten salt fast reactor in the frame of the EVOL and MARS collaborative projects, EPJ Nuclear Sci. Technol. 5, 2, 2019 • Effect of the [U(IV)/U(III)] Ratio on Selective Chromium Corrosion and Tellurium Intergranular Cracking of Hastelloy N alloy in the LiF-BeF2-UF4 Salt, EPJ Nuclear Sci. Technol., Special issue, 2019 U.S. MSR* Development Activities Include Government Support, Industry, and Regulatory Modernization • Department of Energy (DOE)-Office of Nuclear Energy (NE) MSR technical campaign continues into FY’19 • Core R&D through national laboratories • University research (20% of campaign) • Small business opportunities • Gateway for Accelerated Innovations in Nuclear (GAIN) vouchers to provide private company access to national laboratory resources • Multiple industry awards • Additional government activities are more broadly classified as support for advanced non-LWRs • Office of Science and Advanced Research Projects Agency (ARPA-E) projects • Nuclear Regulatory Commission is developing a technology-neutral, performance-based, risk-informed regulatory framework

*MSR support includes both solid (aka FHRs) and liquid fueled concepts

16 Several Projects Related to FHR R&D Have Been Completed in the US Covering a Number of Areas • “Integrated FHR Technology Development: Tritium Management, Materials Testing, Salt Chemistry Control, Thermal Hydraulics and Neutronics, Associated Benchmarking and Commercial Base” • MIT-ANP-TR-18 • Summarizes three years of work done at four universities (MIT, UC-Berkley, U of Wisconsin, and U of New Mexico • “Integrated Approach to Fluoride High Temperature Reactor Technology and Licensing Challenges (FHR-IRP) IRP-14-7829 y3 • 3-year, multi-university study led by Georgia Tech 2015 DOE-NE Industry Award - Cost-Sharing R&D With Industry on a Molten Chloride Fast Reactor

• Completed by 2019 • First U.S. Government liquid-fueled • Supported jointly by U.S. Government and MSR funding in 40 years Early Southern Nuclear validation Services led consortium • Award made following a competitive process • Mid 2020s • $40M of government funding over Critical test 5 years with a substantial private reactor match (>20%)

• By 2035 • Southern Company Services is the Commercial lead for the program prototype

• TerraPower, ORNL, EPRI, and Vanderbilt Image courtesy of TerraPower University are the supporting institutions • ORNL is R&D lead 2018 DOE-NE Industry Awards • Modeling and Optimization of Flow and Heat Transfer in Reactor Components for Molten Chloride Salt Fast Reactor Application • Elysium Industries USA - $3,200,000 • Fluorination of Lithium Fluoride-Beryllium Fluoride Molten Salt Processing • Flibe Energy & PNNL - $2,627,482 • in situ Measurement and Validation of Uranium Molten Salt Properties at Operationally Relevant Temperatures • University of Connecticut (CFA-18-15065) - $799,979 • Development of an MC&A toolbox for liquid- fueled molten salt reactors with online reprocessing • University of Tennessee (CFA-18-15061) - $799,207 • Determination of Molecular Structure and Dynamics of Molten Salts by Advanced Neutron and X-ray Scattering Measurements and Computer Modeling • MIT (CFA-18-15093)- $800,000 • Corrosion Testing of New Alloys and Accompanying On-Line Redox Measurements in ORNL FLiNaK and FLiBe Molten Salt Flow Loops • Georgia Institute of Technology (CFA-18-14977) - $800,000 19 Three Vendors Have Announced Plans for Commercial US MSR Deployment by Early 2030s

TerraPower Kairos Power Terrestrial Energy USA

• Separate effects tests • Pre-conceptual design • Conceptual design – (now) – March 2018 mid-2016 • Integrated effects test • Conceptual – • Vendor phase 1 design (2019) December 2020 review (Canada) – • Test reactor – 30-150 • Preliminary – Before October 2017 MWth – Class 104 2025 • Vendor phase 2 design License (2023-2028) • Detailed – Before 2030 review (Canada) – • Commercial prototype • US demonstration by 2020 (starting 4Q2018) reactor – 600-2500 2030 • Commercialization MWth – Class 103 • Rapid deployment before 2030 License (early 2030s) ramp up in 2030s

20 ORNL Liquid Salt Test Loop (FLiNaK) Restarted in 2018

• Forced-flow loop for component testing • Conducted a number of activities to restart loop • Re-cleaned FLiNaK • Worked with company to design new pressure transducer • Added heaters to ultrasonic flowmeter • Re-calibration of pressure relief valves, gas pressure transducers, mass flow controllers • Worked with GT on corrosion test setup Forced Flow FLiBe Loop Thermal Image, Operating 700°C Hot Side, 650°C Cold Side

March 2019 FLiBe Natural Circulation Loop, Dimensions, Picture, Thermal Image During Operation The DOE and NRC MSR Campaigns Have Produced a Number of R&D Reports • Molten Salt Reactor Salt Processing – Technology Status - INL/EXT-18-51033 https://www.osti.gov/biblio/1484689-molten-salt-reactor-salt-processing-technology-status • Status of Metallic Structural Materials for Molten Salt Reactors - INL/EXT-18-45171 https://www.osti.gov/biblio/1467482-status-metallic-structural-materials-molten-salt-reactors • A Systems Processing Model for Molten Salt Reactor - INL-EXT-18-45007 https://www.osti.gov/biblio/1467477-systems-processing-model-molten-salt-reactors • Thermochemical and Transport Properties Important to Molten Salt Reactor Operation: Off-Gas Performance under Normal Operation and Fission Product Mechanistic Source Term - ORNL/TM-2018/958 https://www.osti.gov/biblio/1479742-thermochemical-transport-properties-important-molten-salt-reactor-operation-off-gas- performance-fission-product-mechanistic-source-term • Phenomena Important in Modeling and Simulation of Molten Salt Reactors – BNL-114869-2018-IR https://www.nrc.gov/docs/ML1812/ML18124A330.pdf • A Safety and Licensing Roadmap to Identify the Research and Development Gaps of Commercial Molten Salt Reactors -ORNL/TM- 2018/944 https://www.osti.gov/biblio/1474561-safety-licensing-roadmap-identify-research-development-gaps-commercial-molten-salt-reactors • Regulatory Gap Analysis of Select NUREG-0800 Chapters for Applicability to Molten Salt Reactors - ORNL/TM-2018/976 https://www.osti.gov/biblio/1476402 • SiC/SiC Composites Technology Gap Analysis for Molten Salt Reactor- ORNL/TM-2018/842 https://www.osti.gov/biblio/1462858-sic-sic-composites-technology-gap-analysis-molten-salt-reactors TMSR Program in China 2MWt TMSR-LF1 demonstration by the end 2020

25 Fluoride Salts Production and Purification

Synthesis technology of nuclear grade FLiBe with boron • High purity FLiNaK batch production, - equivalent < 2 ppm characterization and purification Purification technology of high purity FLiNaK with total • Synthesis of FLiBe and beryllium - oxygen < 100 ppm control method High purity FLiNaK batch production of 10 tons per year • Establishing FLiBe-Th-U fuel salts - Capability of fluoride salt physical properties thermodynamics database - measurement

Fluoride salt Salt production of 10 tons per year FLiBe Salt 22 Production of Nickel-based Alloy

Smelting 6 tons of alloy, developed • Technologies for the smelting, - technologies for processing and welding, processing, and welding of a performance is comparable to Hastelloy N Nickel-based alloy, UNS N10003, - Deformation processing technologies for nickel- based alloys with high Moly, manufactured large China standard GH3535 UNS N10003 seamless pipes

Hot extrusion Pipe processing Welding Component

23 Production of Low Porous Nuclear Grade Graphite • Development of the ultrafine grain nuclear graphite for MSR, involved in the establishment of ASME code of MSR nuclear graphite - Industrial production of ultrafine-grain nuclear graphite NG-CT-50 - Pore < 1 μm, ensured better FLiBe salt infiltration resistance than existing nuclear graphite - Establishing performance database for NG-CT-50 graphite - Participating in the international standards development of MSR nuclear graphite

FLiBe salt infiltration 16 16 FLiBe--700oC, 20h 14 6atm 14 8atm Parameters NG-CT-50 IG-110 12 10atm 燃料球基体石墨 12

10 10

8 8

Pore Dia. (mm) 0.74 2

6 6 浸渗量 (wt.%) Boron (ppm) < 0.05 0.1 4 4 2 2 Ultrafine grain 0 0 nuclear graphite IG-110 NBG-18 NG-CT-10 PB NG-CT-50

24 Material Corrosion Control • Control the structural material corrosion by alloy composition optimization, salt purification and surface treatment

Investigating Developing Corrosion Control Technologies Corrosion Mechanism - Optimize the composition of alloy, diffusion of Cr - Salt impurities - Improve purification technology, minimize - Elements diffusion impurities - Mass transfer - Fluoride salt thermal diffusion coating

GH3535 exposed to Without FTD impurity FLiNaK Coating Corrosion

Oxidation GH3535 exposed to The corrosion attack was heavier in test high purity FLiNaK FTD Coating coupons electric contacted (right) with Composition Optimization (Cr) graphite container than that of the isolated one (left)

25 Pyroprocessing Techniques

• Fluorination and distillation of fluoride salts in cold experiments • Developing fluorides electrochemical separation techniques

- Fluorination for U recovery: Verification of process with in-situ monitoring, use of frozen-wall technique to mitigate corrosion,

derived from high temperature, F2 and liquid fluorides melt. - Distillation for carrier salt purification: Demonstration of a controllable continuous distillation device, the distillation rate is about 6 Kg per hour, and the DF is > 102 for most neutron poisons.

- Fluorides electrochemical separation for U recovery: Electro-deposition of U metal from FLiBe-UF4 melt and recovery > 92%

Electrochemical Fluorination Frozen-wall test Distillation experimental set-up experimental set-up experimental set-up

27 Tritium Measurement and Control

• On-line tritium monitoring • Tritium stripping using bubbling, tritium separation with cryogenics, and tritium storage

Tritium stripping Tritium separation Tritium alloy On-line tritium with bubbling with cryogenics storage monitoring

On-line monitoring of Bubble-size Kr\Xe < 1 ppb and Zr2Fe alloy control, H2 < 1 ppm in (Hydrogen partial HTO, HT, K and Xe, degassing the off gases pressure ratio efficiency > 95% < 0.1 ppm ) Australian MSR Materials Research GH 3535 Creep testing in molten FLiNaK salt Effect of Ion Irradiation on Corrosion

SEM

Euler Map

• GR3535 alloy, FLiNaK salt, 1017 ions/cm2 He+ • He+ ion irradiation increases the thickness of the corrosion layer in the irradiated and corroded sample to more 30 times than in the un-irradiated sample Evidence of preferential grain boundary attack 32 Canadian Nuclear Laboratories Focuses on: Thermophysical Properties of Molten Salts, Reactor Accident Phenomenology, Accident Consequence Evaluation, Advanced Modelling And Economics New MSR related projects (2018-2019): • Sensor monitoring of remote and underground northern structures • Passive safety and heat transport technologies • Corrosion of materials in molten salts • Human performance factors related to operations • Predictive tools to assess safety margins for heat pipe reactors • Development of actinide molten salt fuel synthesis • Evaluation of safety margin to failure conditions for fuel • Methodological basis for transport criticality and radiation safety analysis • Exploring capabilities for ZED-2 as a Physics Test Facility to support MSR design

33 Thank you for your attention