PEACE : a Prototype of the Energy Amplifier for a Clean Environment

1. PEACE :a Prototype of the Energy Amplifier for a Clean Environment Y. Kadi CERN, Switzerland 29 January 2007, Energy Forum, Bergen, Norway Y. Kadi

2. OUTLINE PEACE: an Industrial Prototype of the Energy Amplifier for a Clean Environment • Motivations • General Features of Energy Amplifier Systems • Experimental Validation • Implementation Strategy • Time Schedule Y. Kadi

3. A new primary energy source • By 2050, the world’s consumption (+ 2%/y) should reach 34 TW, of which 20 TW should come from new energy sources:A major innovation is needed in order to replace the expected “decay” of the traditional energy sources! • This implies a strong R&D effort, which is the only hope to solve the energy problem on the long term. This R&D should not exclude any direction a priori! • Renewables • Nuclear (fission and fusion) • Use of hydrogen • Can nuclear energy play a major role? • Nuclear energy has the potential to satisfy the demand for a long time (at least 15 centuries for fission, essentially infinite for fusion if it ever works), and is obviously appealing from the point of view of atmospheric emissions. Y. Kadi

4. Which type of nuclear energy? • Nuclear fusion energy: not yet proven to be practical. Conceptual level not reached (magnetic or inertial confinement?). ITER a step, hopefully in the right direction. • Nuclear fission energy: well understood, and the technology exists, with a long (≥ 50 years) experience, however, present scheme has its own problems: • Military proliferation (production and extraction of plutonium); • Possibility of accidents (Chernobyl [1986]; Three Mile island [1979]); • Waste management. • However, it is not given by Nature, that the way we use nuclear fission energy today is the only and best way to do it. One should rather ask the question:Could nuclear fission be exploited in a way that is acceptable to Society? • To answer this question, Carlo Rubbia and his team at CERN have carried out, in the 1990’s, an extensive experimental programme (FEAT, TARC) which has led to a conceptual design of a new type of nuclear fission system, driven by a proton accelerator, with very attractive properties (Pioneering work by Ernest Lawrence, Wilfrid Bennett Lewis, Hiroshi Takahashi, Charles D. Bowman). Y. Kadi

5. Basic Principle of Energy Amplifier Systems • One way to obtain intense neutron sources is to use a hybrid sub-critical reactor-accelerator system called Accelerator-Driven System:  The accelerator bombards a target with high-energy protons which produces a very intense neutron source through the spallation process.  These neutrons can consequently be multiplied (fission and n,xn) in the sub-critical core which surrounds the spallation target. Y. Kadi

6. General Features of Energy Amplifier Systems Subcritical system driven by a proton accelerator: • Fast neutrons (to fission all transuranic elements) • Fuel cycle based on thorium (minimisation of nuclear waste) • Lead as target to produce neutrons through spallation, as neutron moderator and as heat carrier • Deterministic safety with passive safety elements (protection against core melt down and beam window failure) Y. Kadi

7. General Features of Energy Amplifier Systems Y. Kadi

8. Energy Amplifiers vs Critical Reactors Main objective is to reduce the production of nuclear waste (TRU) • Energy Amplifier : • sub-critical • fast neutrons • Thorium + 233U +TRU (Pu + Minor Actinides) • Reactor : • critical • slow neutrons • Uranium + Pu Y. Kadi

9. Physics of Sub-Critical Systems  EAs operate in a non self-sustained chain reaction mode  minimises criticality and power excursions  EAs are operated in a sub-critical mode stays sub-critical whether accelerator is on or off  extra level of safety against criticality accidents  The accelerator provides a control mechanism for sub-critical systems  more convenient than control rods in critical reactor  safety concerns, neutron economy EAs provide a decoupling of the neutron source (spallation source) from the fissile fuel (fission neutrons) EAs accept fuels that would not be acceptable in critical reactors  Minor Actinides  High Pu content  LLFF... Y. Kadi

10. Safety margin from prompt criticality • For a critical system, it is measured by the fraction of delayed neutrons. For the Energy Amplifier, it is an intrinsic property, and can be chosen. • Subcriticality implies strong damping of reaction to reactivity insertion, making the system very stable (presence of higher modes in neutron flux). Keff < ksource The parameters of the system can be chosen so that k < 1 at all times. Y. Kadi

11. Reactivity Insertions • Figure extracted from C. Rubbia et al., CERN/AT/95-53 9 (ET) showing the effect of a rapid reactivity insertion in the Energy Amplifier for two values of subcriticality (0.98 and 0.96), compared with a Fast Breeder Critical Reactor. • 2.5 $ (Dk/k ~ 6.510–3) of reactivity change corresponds to the sudden extraction of all control rods from the reactor. There is a spectacular difference between a critical reactor and an EA (reactivity in $ = r/b; r = (k–1)/k) : Y. Kadi

12. Energy Amplifiers vs Critical Reactors Main objective is to reduce the production of nuclear waste (TRU) • Energy Amplifier : • sub-critical • fast neutrons • Thorium + 233U +TRU (Pu + Minor Actinides) • Reactor : • critical • slow neutrons • Uranium + Pu Y. Kadi

13. Nuclear waste: the priority in developed countries • TRU:(1.1%)produced by neutron capture;dominated by plutonium: destroy them through fission • Fission Fragments:(4%)the results of fissions transform them into stable elements through neutron capture Y. Kadi

14. Evolution of radiotoxicity of nuclear waste • TRU constitute by far the main waste problem [long lifetime – reactivity]. The system should be optimized to destroy TRU. Same as optimizing for a system that minimises TRU production. Interesting for energy production! Typically 250kg of TRU and 830 kg of FF per Gwe Y. Kadi

15. Maximizing fission probability The strategy consists in using the hardest possible neutron flux, so that all actinides can fission instead of accumulating as waste. Note: thermal fission resilient elements Y. Kadi

16. Fast neutrons and high burn-up Fast neutrons allow a more efficient use of the fuel by allowing an extended burnup Y. Kadi

17. Energy Amplifiers vs Critical Reactors Main objective is to reduce the production of nuclear waste (TRU) • Energy Amplifier : • sub-critical • fast neutrons • Thorium + 233U +TRU (Pu + Minor Actinides) • Reactor : • critical • slow neutrons • Uranium + Pu Y. Kadi

18. Thorium as fuel in a system breeding 233U It is the presence of the accelerator which makes it possible to choose the optimum fuel. Low equilibrium concentration of TRU makes the system favourable for their elimination: Pu 10–4 in Th vs 12% in U. Y. Kadi

19. Radiotoxicity • The radiotoxicity of spent fuel reaches the level of coal ashes after only 500 years, and is similar to what is predicted for future hypothetical fusion systems Y. Kadi

20. Why not Thorium Reactors • Thorium is not vigorously fissile => it needs a source of neutrons to kick-off the chain reaction. • Thorium also cannot maintain criticality on its own => it cannot sustain a chain reaction once it has been started (Pa-233) • The question until now has been how to provide thorium fuel with enough neutrons to keep the reaction going and do so in an efficient and economical way. Y. Kadi

21. MOTIVATION for ADS • Accessible, clean & cheap energy for countries requiring more energy to reach normal development. • Nuclear energy without accidents and radioactive waste. (sub-critical & fast neutrons) • Nuclear energy without proliferation risks (Th fuel) Y. Kadi

22. OUTLINE PEACE: an Industrial Prototype of the Energy Amplifier for a Clean Environment • Motivations • General Features of Energy Amplifier Systems • Experimental Validation • Implementation Strategy • Time Schedule Y. Kadi

23. The FEAT experiment 3.6 tons of natural uranium Y. Kadi

24. The TARC Experiment Y. Kadi

25. Transmutation of Nuclear Waste: Fission Products • Fission Fragments activity and toxicity after 1000 years of cool-down in a Secular Repository • (Values are given for 1 GWe ´ year) Y. Kadi

26. Experimental Setup Y. Kadi

27. TARC Results (2) Y. Kadi

28. R&D Activity in Europe Vast R&D activity in Europe over last 10 years: 12 countries, 43 institutions EU  31 MEuros Member States 100 MEuros Y. Kadi

29. STELLA Loop CIRCE Loop CEA ENEA VICE Loop CHEOPE Loop CorrWett Loop SCK-CEN ENEA PSI CIRCO Loop TALL Loop CIEMAT KTH DEMETRA: Test Facilities • In FP5, a complementory combination of test facilities was set up in Europe. • EUROTRANS is fully using these test facilities. Y. Kadi

30. NUDATA: Experimental Facilities GSI @ Darmstadt (Germany) Gelina @ Geel (UE-Belgium) nTOF @ CERN (Switzerland) and its TAS g-calorimeter Neutron capture (n,g) resonances in one actinide Cyclotron @ Uppsala (Sweden) Y. Kadi

31. MEGAPIE TARGET • MEGAPIE Project at PSI • 0.59 GeV proton beam • 1.3 MW beam power • Goals: • Demonstrate feasablility • One year service life • Operating since August 2006 F. Groeschel et al. (PSI) Proton Beam Y. Kadi

32. SINQ SPALLATION NEUTRON SOURCE Y. Kadi

33. Open Questions • The material selection problem for the internal core structures as well as for the spallation target module and fuel cladding in contact with LBE; • The HLM technology should be answering the problems of LBE conditioning and filtering in pool design conditions; • The development of the needed instrumentation for LBE quality monitoring in order to guarantee a safe and efficient operation of LBE cooled ADS: O2-Meters, ultrasonic visualisation under LBE, HLM Free surface monitoring, sub-criticality monitoring, LBE velocity field measurement; Y. Kadi

34. Open Questions • Key Accelerator components should be demonstrated, namely the reliable working for periods of 3 months of the injector; • The spallation module based on the windowless concept (most promising of achieving high performance core) should be fully designed from the mechanical and thermal-hydraulic aspects; • The coupling of the ADS components (accelerator, spallation module and a sub-critical core) should be realised at realistic power that would allow to study the thermal feedback reactivity assessment, the on-line subcriticality monitoring and control at various keff values. Y. Kadi

35. 2+ UO 2 UO +PuO 2 2 2+ PuO 2 ROAD MAP FOR PEACE Technology of pyrochemical reprocessing of fuel High power accelerators technology Technologies of fast reactors with lead-bismuth coolant Liquid metal targets technology Y. Kadi

36. Accelerator choice • Cyclotron = MODULAR, realised on industrial scale Cost effective ; applicable in isolated regions ;applicable for desalination & cogeneration • Linear accelerator = Solution for Research Centres & highly centralised production Y. Kadi

37. The SVBR-75/100 MWe Reactor Unit • Integral design with the steam generators sitting in the same Pb-Bi pool at 400-480ºC; • Russia built 8 Alfa-Class submarines, each powered by a compact 155MWth Pb-Bi cooled reactor, and 80 reactor-yrs operational experience was acquired with these; • As follow-up of Russian programme of Pb-Bi cooled fast neutron reactors for Alpha type submarines, the multi-purpose reactor module SBVR75 is now available on the “market” (90M$, Stephanov et al. 1998, Gidropress). Y. Kadi

38. Aqueous method (Japan) Y. Kadi

39. Pyro-processing • Principle Electro-refining in a molten salt solution with electrodes at different potentials • Actinides Separated from Fission Products and high level waste: Plutonium is combined with minor Actinides (Np, Am, Cm) and an approximately equal amount of U • fully tested at the laboratory level • Very efficient (> 99.9%) • No effluents waste, all chemicals recycled: no discharges in the environment • Small size and easy to operate: it may be located on the reactor site or near by, minimising fuel transport • Non proliferating: all TRU’s always intimately mixed • Small batches: no criticality risks. Y. Kadi

40. The Prototype of the Energy Amplifier for a Clean Energy Y. Kadi

41. The PEACE : Plant Layout Y. Kadi

42. The modified version of SVBR-75 reactor for PEACE Y. Kadi

43. The PEACE : Global Parameters Y. Kadi

44. The PEACE : Transmutation Rates Plutonium incineration in ThPu based fuel is more efficient and settles to approximately 43 kg/TWh, namely 4 times what is produced by a standard PWR (per unit energy). The minor actinide production is very limited in this case. Long-Lived Fission products incineration is made possible in a very efficient way through the use of the Adiabatic Resonance Crossing Method. Such a machine could in principle incinerate up to 4 times what is produced by a standard PWR (per unit energy). Y. Kadi

45. Y. Kadi

46. The Generalized Stages for Realizing the PEACE Program Y. Kadi

47. Time Schedule Y. Kadi

48. R&D Program Partnership Network • Accelerator CERN (CH), PSI (CH), AIMA (F), IBA (B) • Spallation source • Basic spallation data CERN (CH), GSI (D), PSI (CH) • Feasibility of the windowless design UCL (B), FZR (D), FZK(D), NRG (NL), CEA (F) + ENEA (I) + IPUL (Latvia) • Subcritical assembly  • RSC “Kurchatov Institute”, Moscow – designing target – blanket systems; investigation and justification of the fuel cycle in transmutation systems, including radiochemical problems. • SSC RF IPPE, Obninsk – target – blanket system construction at the SSC RF IPPE site, the functions of designer and production engineer of the element (component) base for the blanket. • OKB “Hydropress”, Podolsk – Chief designer of the target – blanket system. • GSPI and VNIPIET, St. – Petersburg – Design work at the SSC RF IPPE site. • SSC RF _ VNIINM, Moscow – MOX fuel development and justification; • IYaI RAN, Troitsk – R&D work in justification of subcritical system physics. • NIKIET, Moscow – Chief designer of the equipment for the IYaI RAN site. • ENEA (I), CEA (F), BN (B), UoK-UI (LT), TEE (B),CIEMAT (SP) • Fuel  US, EUR, INDIA, RUSSIA • Safety  EUR, RUSSIA • RoboticsEUR • Building  EUR Y. Kadi

49. Why such a delay ? • The option of high level waste transmutation via ADS is not yet fully accepted by all European nuclear countries or at least a majority of them as the most appropriate way of doing it; • Besides this situation one should mention that in Europe there are many fuel cycle scenarios in application ranging from the once-through scenario up to the double-strata one. • There are also various policies regarding nuclear energy ranging from the continuous development up to the phase out policy Y. Kadi

50. GFR Y. Kadi