Future nuclear systems: fuel cycle options and guidelines for research

Transcription

1 OECD Nuclear Energy Agency 11th Information Exchange Meeting on Actinide and Fission Product Partitioning and Transmutation Future nuclear systems: fuel cycle options and guidelines for research Bernard Boullis, Dominique Warin, France 1

2 The French electricity - Nuclear > 75 % of electricity generation - Low-carbon energy mix : # 4g CO2 per kwh Gr avelines Flamanville Penly Paluel Chooz Cat tenom Nogent Seine St Laurent Dampierre Fessenheim Chinon Belleville Civaux Blayais Golfech Bugey St Alban Cruas Tricastin 900 MW MW MW fossil nuclear - 58 PWR - 63 GWe - >410 TWh per year hydro 2

3 Closing the Fuel cycle with processing an industrial reality The example of the French situation : Natural Uranium Chemistry 58 PWRs 410 TWh annually > 75 % of French electric production Ultimate Wasre Disposal Mines Uranium recyclable Plutonium Recycling : MOX Fuel fabrication Enrichment Enriched Uranium Fuel Fabric. Fuel processing : more than 25 years of experience 1200 t HM /yr of spent fuel discharged from the French PWRs 850 t HM /yr of reprocessed spent fuel domestic + foreign Until now: ~ t HM spent fuel reprocessed Spent Fuel Reprocessing Reactors & Services 150 t HM /yr MOX fuel produced and used in 22 PWRs U recycled in 4 PWRs Front-End Sector Reactors & Services Sector Back-End Sector 3

4 Recycling technologies : decades R and D! high yields SPENT FUEL HNO 3 TBP U Pu DISSOLUTION U, Pu, FPs,MAs solution EXTRACTION HULLS FPs, MAs technological waste low amounts 4

5 Final waste vitrification 180 liters #15% FPs # 10 glass canisters /reactor 1GWe /year --- # 600 canisters /year 5

6 Glass canisters disposal in the deep geological repository (ANDRA, «Clay Report», 2005) 1mSv/y Dose at final outlet 1μSv/y Time after disposal y 1 M y 6

7 Current recycling strategy : the rationale - saving uranium resources, still at low scale (#10% of French nuclear electricity from MOX fuels) - mastering the growth of plutonium inventory (Pu flux adequacy : Pu from processing= Pu refueled) - safe and secure ultimate glass waste, without plutonium - the plutonium available for future use is safely concentrated in MOX spent fuels (7 UOX -> 1 MOX) - an already large industrial experience, operated under international safeguards ( # tons SNF reprocessed, # 2000 tons MOX produced) to be pursued with Generation III reactors 7

8 World context : a very significant energy need in the near-future World population SOURCE : AIEA INDE CHINE ays émergents MONDE JAPON FRANCE Allem agne U.E. U.S.A. 0,2 0,7 0,8 1,6 1,1 G.hab 1,4 G.hab 3,9 4,0 4,1 3,8 Unavoidable growing 8, Consommation Energy consumption/inhabitant d'énergie par habitant (Tep) (TEP) Significant increase of the energy need, even when promoting green economy likely increase of world population: up to ~ by 2100 economic growing of Asian countries, especially India and China The increase of electricity is still much higher, due to energy transfer from fossil energies 8

9 Towards a sustainable nuclear energy «A development which meets the needs of the present, without compromising the ability of future generations to meet their own needs» Safety and reliability Mastered and limited risks Environmental-friendly Low-GHG emission Resources preservation Sustainability is a must Reasonable economic costs Energetic independence Available resources 9

10 Long term sustainable nuclear systems Fast Reactors, the best answer - efficient burning of plutonium - full use of uranium - no enrichment needs - potentialities at a later step for improving waste management by minor actinide recycling Fission/Absorpt U235 U238 Np237 Pu238 Pu239 Pu240 Pu241 Pu242 Am241 Robert N. Hill Argonne National Laboratory 233 rd ACS National Meeting Chicago,, 2007 Am243 Cm244 PWR SFR 10

11 Long term sustainable nuclear systems MOX-FR 450t FRs used MOX-FR 450t FUEL FABRICATION RECYCLING depleted uranium (40t) Plutonium (#20%) Uranium (#80%) Actinide multi-recycle in a FR fleet ( principle values, self-balanced fleet, 60 GW/y) (minor actinides (# 5t)) WASTE FPs (MAs) (40t) A progressive deployment? - initially fueled with plutonium, coming from spent MOX - breeding gain could be adjusted in the future (according to energy needs) 11

12 From PWRs to FRs a French schematic pathway Installed capacity (MWe) ASTRID Fast reactor Prototype Existing fleet 40-year plant life Plant life extension beyond 40 years?? Generation 3+ Generation Average plant life : 48 years 12

13 The 1991 and 2006 French Acts: frame of the Program December 30, 1991 and June 28, 2006 Three Research thematics for nuclear waste management: recycle by P and T to decrease waste amount and toxicity geological deep repository, retrievable confinement and interim storage A roadmap 2012 : industrial potentialities of the diverse recycling options, and decision to build a prototype for transmutation tests by : repository defined, and operation by

14 Fuel cycle technologies : guidelines for R and D 1- Adaptation (specific or innovative fuels) 14

15 Fuel cycle technologies : guidelines for R and D 1- Adaptation (specific or innovative fuels) 2- Improvements (a «sustainable goal» ) 15

16 Current improvement: increasing proliferation-resistance of Pu-recycling PUREX MELOX In order to avoid production of pure Pu in the recycling process, implementation of the COEX TM process Co-extraction of U and Pu Oxalic coconversion of U and Pu: precipitation of oxalic solution, then calcination to UPu oxide solid solution Pu(IV) U(IV)+Pu(III) L15 - ATALANTE Pu IV (C 2 O 4 ) 2.6 H 2 O L15 - ATALANTE (N 2 H 5+,H + ) 2,9 U IV 1,1Pu III 0,9 (C 2 O 4 ) 5.nH 2 O COEX TM 16

17 Current improvement for vitrification : the cold crucible technology hot wall vitrification process CCIM vitrification process Glass frit Waste stream Calciner Glass frit Waste stream Calciner Hot wall crucible CCIM Glass canister Glass canister Cooled wall, direct induction heating Corrosion issues drastically decreased Higher temperature, higher reactivity, FPs higher concentration glass in operation at La Hague,

18 Fuel cycle technologies : guidelines for R and D 1- Adaptation (specific or innovative fuels) 2- Improvements (a «sustainable goal» ) 3- Exploration P and T, minor actinide recycling 18

19 Minor actinide recycling: drivers 1mSv/y 1μSv/y (ANDRA, «CLAY REPORT», 2005) 1My REPOSITORY «FOOTPRINT» FINAL WASTE RADIOTOXICITY HA area: 110 ha HA area: 390 ha Radiotoxicité relative U ore ,1 SNF direct disposal Current glasses MA transmutation Temps (années) Am transmutation-120y Without transmutation-120y 19

20 MA Partitioning and Transmutation: the 2012 milestone Design Separation processes Transmutation devices Transmutation fuels for industrial implementation Assess benefits / costs of MA P and T strategies Explore transition scenarios MA = Am, Cm, Np Interest of a specific approach vs. grouped approach 20

21 MA partitioning options Grouped separation: Date of HA test Spent fuel GANEX-1 GANEX-2 FPs U Pu Np Am Cm Enhanced separation: Spent fuel U (Np) PUREX /COEX (U)Pu(Np) Sole-Am separation: DIAMEX /SANEX or SANEX-TODGA Am Cm FPs Spent fuel PUREX /COEX EXAm FPs & Cm U (Np) (U) Pu (Np) Am 21

22 22 MA Recycling options HOMOGENEOUS (#1% MA, diluted in the fuel) Once-through targets (inert matrix) Multi-recycled MA-bearing blankets (# 10-20% MA on UO2) HETEROGENEOUS: «DEDICATED STRATA» (ADS)

23 Heterogeneous recycling: an option for MA transmutation CORE :UPuO 2 BLANKETS : UAmO 2 or UAmCmO 2 Pu U-Pu MA FP U-MA Reprocessing Unit 23

24 Am Transmutation 238 Np 238 Pu 239 Np β- 2,36j 239 Pu 240 Pu ECRIX in Phénix 241 Pu 241 Am 90% transmuted 30% fissionned 242 Pu 243 Pu β+ 16,02h 17,3% β- 4,96h 242 Am 243 Am 244 Am β- 16,02h 82,7 % β- 10,1h 242 Cm 243 Cm 244 Cm Initial AmO 2 Metallic FPs 24

25 Fuel cycle technologies : guidelines for R and D 1- Adaptation (specific or innovative fuels) 2- Improvements (a «sustainable goal» ) 3- Exploration P and T, minor actinide recycling 4- Alternative process «Dry processes» 25

26 Fleet and Fuels will evolve LWRs FRs TODAY (HBU, MOX) THEN? THEN? (?) (feeding FRs) (multi-recycle FRs) (?) THEN? (minor actinide recycle? ) Processes and technologies : flexible, efficient, cost-effective, clean, proliferation-resistant 26

27 En résumé towards sustainable nuclear energy, the 2012 milestone Nuclear energy, as a GHG-free energy, is anticipated to develop in the next century to answer the increase of energy needs and has to be sustainable Current Pu mono-recycling with MOX in PWR already contributes in France to decrease waste volume and toxicity, while saving U resources first step to sustainability Increasing sustainability for nuclear energy requires improved actinide recycling, and shifting stepwise towards fast reactor systems in order to: 1 st step : multi-recycle Pu and U for saving resources 2 nd step : recycle minor actinides for stabilizing their inventories, reducing the waste toxicity, reducing the repository volumes and costs strong implications for public acceptance In the framework of the 2006 waste management Act, France developed and has now a portfolio of several MA partitioning processes that basically demonstrate the feasibility of their recycling, in homogeneous or heterogeneous mode 27

28 En résumé towards sustainable nuclear energy, the 2012 milestone For 2012, relative benefits of these different options have to be assessed in terms of economy, densification of the final storage, industrial feasibility, flexibility, safety, proliferation resistance, Industrial feasibility : design / optimize separation processes, transmutation fuels and their fabrication processes, and gather technical elements for industrial operation evaluation Both science-based and process-oriented actinide separation and transmutation research is continuing at CEA, within French and international collaborations (EU ACSEPT project, ACTINET-I3 network, USA, Japan, Russia, ) An integrated test is planned : closing the Am cycle by preparing Am-bearing fuels using Am recovered from spent fuel by the EXAm process: fuel to be tested at pellet scale under fast flux, then after 2020 at pin scale using the ALFA (Atalante Laboratory For Actinides bearing fuel manufacturing) and ASTRID (Advanced Sodium Technological Reactor for Industrial Demonstration) 28