P. Dařílek. Winter seminar Generation-IV Nuclear Reactors 8-10 February, 2010 Demänová, Slovakia

Transcription

1 Molten salt concept P. Dařílek Winter seminar Generation-IV Nuclear Reactors 8-10 February, 2010 Demänová, Slovakia 1/35

2 Content History Molten salt reactor MSR concepts Selected aspects International projects Perspectives 2/35

3 History THE AMERICAN PROGRAMMES (ORNL) 1954 AIRCRAFT REACTOR EXPERIMENT (ARE) VALIDITY OF THE MSR CONCEPT MSRE MOLTEN SALT REACTOR EXPERIMENT SCIENTIFIC AND TECHNOLOGICAL VIABILITY MOLTEN SALT BREEDER REACTOR (MSBR) PROJECT OF BREEDER REACTOR (1000 MWe) 3/35

4 History AIRCRAFT REACTOR EXPERIMENT (ARE>ANP) SMALL REACTOR 2,5 MWth FUEL: 235 U FUEL SALT: NaF-ZrF4-UF4 MODERATOR: BeO CORE AND TUBES: INCONEL PRIMARY COOLANT OUTPUT TEMPERATURE: 860ºC SECONDARY COOLANT: He OVERAL EXPLOITATION EXPERIENCE: 1000 MWh 4/35

5 History AIRCRAFT NUCLEAR PROPULSION (ANP) TWO AIRCRAFTS B test flights during /35

6 History MSRE (MOLTEN SALT REACTOR EXPERIMENT) EXPERIMENTAL REACTOR 8 MWth(ORNL) 3 FUEL TYPES: URANIUM ENRICHED 30% WITH 235 U PURE 233 U 239 Pu FUEL SALT 66%LiF-29%BeF 2-5%ZrF 4-0,2%UF 4 OPERATED 5 YEARS (LOAD FACTOR 85%) WITHOUT ANY INCIDENT 6/35

7 History MSRE (MOLTEN SALT REACTOR EXPERIMENT) EXPERIMENTAL REACTOR 8 MWth(ORNL) ONE-LOOP CORE MODERATOR: GRAPHITE CORE VESSEL AND TUBES: INOR-8 (LATER HASTELLOY N) SECONDARY COOLANT: LiF-BeF 2 FUEL SALT PARAMETERS MELTING: 434 ºC CORE INPUT: 635 ºC CORE OUTPUT: 663 ºC DENSITY: 2270 kg/m 3 HEAT CAPACITY: 1968 J/kg.K SATURATED STEAM PRESSURE: 13 Pa MSRE SHUTDOWN IN /35

8 History MSBR PROJECT (MOLTEN SALT BREEDER REACTOR) 2250 MWth 1000 MWe FUEL SALT 71%LiF-16%BeF 2-12%ThF 4-0,3%UF 4 TWO ZONES CORE ( FISSILE AND FERTILE BR=1.06 CONTINUOUS FUEL REPROCESSING (REPROCESSING TIME ~ 10 DAYS) 8/35

9 History MSBR PROJECT (MOLTEN SALT BREEDER REACTOR) ONE-LOOP CORE MODERATOR: GRAPHITE PRIMARY AND SECONDARY CIRCUIT: HASTELLOY N (modified) SECONDARY COOLANT: 92%NaBF 4-8%NaF 2 PROJECT STOPPED IN /35

10 Molten salt reactor (MSR) MSR IN THE GENERATION IV ROADMAP 10/35

11 Molten salt reactor (MSR) MSR attractiveness restored by partitioning and transmutation interest Advantages vs. solid-fuel reactors: - no solid fuel fabrication and handling - lower fissile inventory - no radiation damage limit on fuel burn-up up - no solid spent nuclear fuel - single isotopic composition of fuel in the reactor - low pressure in the core - spent fuel prepared for partitioning - high temperature applications 11/35

12 Family Concepts F/T Fuel cycle MSR- Breeder MSR concepts Thermal power (MW) Comments MSBR T 233 U/Th Reference breeder concept BR > 1.05 Feedback reactivity coefficient > 0 (slightly) AMSTER-B T 233 U/Th BR > 0.95 REBUS F U/Pu FUJI T 233 U/Th el. TMSR T or F 233 U/Th BR > 1 Feedback reactivity coefficient < 0 (T and F) MSR-Burner AMSTER-I T U-Pu-MA SPHINX F Pu-MA MOSART F Pu-MA Feedback reactivity coefficient < 0 12/35

13 Liquid Metal cooled FBR MSR concepts molten salts in advanced reactors - Safety demonstration (void coefficient, reaction Existing Na-air and Na-water ) Sodium FR - Economics Innovating SFR Lead FR Other alloys? Molten salt cooled FR MSR Gaz Cooled Reactors Molten Salt Breeder Reactor Molten Salt MA Burner Higher Power VHTR AHTR Sustainability Thorium breeder Unat/Pu breeder (Fast) Thorium support / AMSTER VHTR Thorium fuel Fast spectrum Thermal spectrum Without support (Fast) / MOSART, SPHINX GFR 13/35

14 MSR concepts AMSTER (ACTINIDE MOLTEN SALT TRANSMUTER) 2 VERSIONS : AMSTER-I (INCINERATOR) AMSTER-B (BREEDER) REPROCESSING TIME ~ 300 EFPD pump molten salt (fuel + coolant), LiF - BeF 2 - XF C turbine graphite moderator on-line processing plant 550 c salt/salt exchanger 1) FP partitioning 2) heavy atoms feeding steam generator (or salt/he exchanger) ONE SALT, 2 MODERATION ZONES 13 cm salt graphite 14/35

15 TMSR (THORIUM MOLTEN SALT REACTOR) TMSR REFERENCE DESIGN General parameters: - total power : 2500 MWth (1000 MWe) - salt composition : 78% LiF 21.4% ThF 4 0.6% UF 4 - temperature : about 600 C Geometrical parameters: - core radius : 1.6 m - hexagon size : 15 cm - channel radius: 8.5 cm - salt volume : 20 m 3 - fertile blancket : yes - core shape : cylindrical (H=D) MSR concepts SYSTEMATIC EXPLORATION OF PARAMETERS AND CONSTRAINTS TWO SALTS 15/35

16 MSR concepts Final scheme of the SPHINX transmuter elementary module for the BLANKA 4 rig design 16/35

17 MSR concepts MOlten Salt Actinide Recycler Transmuter (MOSART) (MOSART has been designed during the ISTC-1606 project) General parameters: - total power : 2400 MWt (1100 MWe) - salt composition : 58NaF-15LiF-27BeF2-0.8AnF3 T melt,0 C LiF NaF BeF High solubility for actinide and lanthanide trifluorides (> 2 mol% at 600 C) Gas line Lead Shielding Fuel salt level Reflector Shielding Fuel salt outlet Reflector cooling Reflector Support ring React. Coeff. [pcm/k] Very negative reactivity coefficient (~ -3 pcm/k) Vessel Reactivity Coeff. MOSART Distribution plate Fuel salt inlet window -1.0 Shielding -1.5 Doppler -2.0 Total Fuel salt inlet Fuel salt drain line m Fuel Temperature [K] 0 Fig. 4. MOSART core MOSART CONCEPT (2400 MWt) 17/35

18 MSR concepts Advanced High Temperature Reactor with Metallic reactor vessel Internals (AHTR-MI) 18/35

19 Selected aspects SALT SELECTION Physical behaviour - large heat capacity - low melting point - high boiling point - density - viscosity - velocity Core physics - small capture cross-section - non moderating - low neutronic activation - stable under irradiation - reactivity Safety - feedback reactivity - toxicity - optical transparency - in-service inspection Salt selection Non proliferation Chemistry - chemical stability - corrosion (clad, pipings, reflectors) - chemical reactivity (water, air, ) - actinide solubility - salt clean-up Economics - cost of salt components - maintenance - component cost - resource availability - compatibility with cheap structural materials 19/35

20 Selected aspects SALT SELECTION Reactor type MSR- Breeder Neutron spectrum Thermal Fast Application Reference Alternatives Fuel 7 LiF-BeF2-ThF4 Coolant Fuel NaF-NaBF 4 LiF-ThF 4 LiF-BeF 2 LiF-CaF 2 -ThF 4 NaCl-UCl 3 -PuCl 3 Coolant NaF-NaBF 4 NaF-LiF-KF-AnF 3 MSR-Burner Fast Fuel NaF-LiF-BeF 2 -AnF 3 NaF-LiF-RbF-AnF 3 AHTR Thermal Coolant 7 LiF-BeF 2 VHTR Thermal Heat transfer LiF-NaF-KF LiCl-KCl-MgCl 2 LSFR Fast Coolant NaCl-KCl-MgCl 2 NaF-KF-ZrF 4 SFR Fast Heat transfer NaNO 3 -KNO 3 An represents the actinides Pu, Am and Cm Probable salt compositions for different applications 20/35

21 Requirements: Selected aspects METALLIC MATERIALS - low corrosion rate at liquid fluoride salts (caused by impurities) - long service lifetime at high temperature (creep) - compatibility with molten media - resistance against high-temperature air oxidation - resistence against radiation damage Alloy Cr Mo W Ta Al Ti Fe C Co Ni Nb Zr Hastelloy- X bal. Hastelloy-N M bal. 0.6 HP- modified 24 bal Nickel Incoloy-800H bal Haynes Nb-1Zr Haynes Inconel Haynes Hastelloy B bal /35

22 Selected aspects GRAPHITE Graphite functions: - moderator - reflector Graphite in MSR: - stabil against radiation-induced distortion - low permeability to salt ingress - low permeability to gas ingress conventional graphite (cracks and crevices) salt intrusion limitation fine grained nuclear grade graphite (porosity) xenon gas exclusion pyrocarbon sealing 22/35

23 Selected aspects NEUTRONICS and DYNAMICS Objectives: fuel cycle efficiency breeding or burning safety DYN3D-MSR delayed neutrons precursors drift: 2 C j (z,t)/ t + (v n.c j (z,t))/ z = (1/k eff ). β g,j.γ.σ f,g.φ g (z,t) λ j.c j (z,t) g=1 23/35

24 Selected aspects NEUTRONICS and DYNAMICS MOSART DESIGN: Inlet at Bottom Periphery (H inlet =50cm), with Conic Top Reflector [K] T f max =1107K T r max =1142K <T f > out =988K without distribution plate with distribution plate 24/35

25 Selected aspects PROCESSING and REPROCESSING Tasks: removal of fission products (neutron poisons) extraction of newly constituted fisile material (or precursors) refuelling by fresh fissile/fertile material Reprocessing methods: classical hydrometallurgical PUREX process pyrochemical separation methods advanced pyrochemical technologies fluoride volatility process 25/35

26 Selected aspects PROCESSING and REPROCESSING Conceptual flow-sheet of MSR-SPHINX (An-burner) fuel salt clean up 26/35

27 Selected aspects PROCESSING and REPROCESSING Conceptual scheme of Li,Na,Be/F MOSART fuel salt clean up 27/35

28 Selected aspects NON-PROLIFERATION Th-breeder special non-proliferation vigilance: pure 233 U generation from separated 233 Pa Proliferation resistance increase: denaturation of separated Pa by dirty uranium from MSR fuel circuit ( 232 U, 234 U) denaturation of U in MSR by 238 U (but Pu) 28/35

29 International projects EUROPE (FP5-6) - FROM MOST TO SUMO A continuous and coordinated activity (European network) since 2001 MOST CONFIRMATION OF MSR POTENTIAL IDENTIFICATION OF KEY-ISSUES (MSBR) 6 countries + Euratom LICORN ALISIA SUMO STRENGHTHENING OF EUROPEAN NETWORK FOLLOW-UP OF R&D PROGRESS REVIEW OF LIQUID SALTS FOR VARIOUS APPLIS PREPARATION OF EUROPEAN MSR ROADMAP > 2009 FEASIBILITY DEMONSTRATION OF TMSR-NM (PRE-CONCEPTUAL TMSR-NM DESIGN) 7 countries + Euratom + Russia 7 countries + Euratom + Russia 29/35

30 International projects AMSTER (France) SPHINX (Czech republic) ISTC 1606 MOSART (Russia) AHTR (USA) Generation IV International Forum 30/35

31 Perspectives 31/35

32 References Renault C.: ISTC-1606 Liquid Salts Potential for Nuclear Applications, ISTC Training, Cadarache, March 3-7, 2008 Uhlíř J.: Kapalná jaderná paliva a pyrochemické separační methody, Internal seminar, VUJE Trnava a KJFT FEI STU Bratislava, November 2007 Sabelová V.: Fluoridový reaktor na zneškodňovanie aktinoidov z vyhoreného jadrového paliva, Bacherol thesis, FEI STU, May 2008 Benes O., Cabet C., Delpech S., Hosnedl P., Könings R., Lecarpentier D., Matal O., Merle-Lucotte E., Renault C., Uhlíř J.: Assessment of Liquid Salts for Innovative Applications, Deliverable D50, FP6 SSA ALISIA, September /35

33 Lecarpentier D.: Different Kinds of Molten Salt Reactors, ISTC-1606 Training, Cadarache, March 3-7, 2008 Váša I., Hron M.: Experimental Verification of Nuclear Reactor Systems with Liquid Fuel Based on Molten Salt Fluorides, ISTC-1606 Training, Cadarache, March 3-7, 2008 Merle-Lucotte E., Thevenon C.: ALISIA WP5: Design and Safety, ALISIA Info Day, March 2008 Peterson P. F., Zhao H.: Preliminary Design Description for a First- Generation Liquid-Salt VHTR with Metallic Vessel Internals (AHTR- MI), Report UCBTH , U.C.Berkeley, December 2005 Křepel J.: Dynamics of Molten Salt Reactors, Doctoral Thesis, Dresden /35

34 Ignatiev V.: Progress in ISTC-1606 Phase 2, ISTC-1606 Training, Cadarache, March 3-7, /35

35 Thank you for your attention 35/35