Back End Fuel Cycle: Indian Scenario Madhuri Shetty Nuclear Recycle Group Bhabha Atomic Research Centre, Mumbai Technical Meeting on Integrated Approaches to the Back End of the Fuel Cycle Vienna, 17 – 19 July 2018
Outline • India ’ s Three stage Nuclear program • Fuel cycle options: Open fuel cycle and Closed fuel cycle • Strategies of spent management practices in India • Integrated Nuclear Recycle Plant: A new concept • Interfaces in back end cycle activities • Information & Knowledge management • Role of Regulatory body • Conclusion
INDIAN NUCLEAR PROGRAM PRESENT SCENARIO ➢ At present 22 reactors are in operation ➢ Another 9 reactors are under construction while 10 have been approved and in process of siting ➢ There are various research reactors also which are operational ➢ Further planning to add more capacity in future to reach 63 GWe by 2050
India ’ s Three Stage Nuclear Power Programme • India has limited Uranium resources and abundant Thorium resources • A Three Stage Nuclear Programme was designed by Dr. H. J. Bhabha for optimum utilization of limited uranium and abundant thorium . • Closing fuel cycle by reprocessing and recycling fissile & fertile material back into rector system helps in exploiting the full potential of nuclear power and maximize the resource utilization • Success of closed cycle would depend on utilization of Plutonium for power generation as it can increase the quantum of energy derived from Uranium • Reprocessing is a vital link between the stages of three stage nuclear energy programme
Indian Three stage Nuclear Power Program The goal of three stage Indian nuclear power programme is long term resource sustainability 540 MW Pressurized Heavy Water Advanced Heavy Water Fast Breeder Reactor www.indiaatcop22.org reactor (PHWR) Reactor (AHWR)
Fuel cycle options Huge energy potential !! Spent Fuel cooling Fuel Fissile partly spent Nuclear & final disposal in Reactor Fissile + Fertile Fertile partly Geological converted Repository Open or Once Through Fuel Cycle
Fuel cycle options Huge energy potential !! Fissile partly Nuclear spent Fuel Reprocessing Reactor Fertile partly Fissile + Fertile converted HLW to Interim storage and finally to Deep Repository Fuel Fabrication Fertile + Fissile Closed Fuel Cycle
India ’ s strategy: Closed Fuel Cycle
Features of closed fuel cycle ▪ With reprocessing and recycle energy potential is enhanced several ten folds and even our limited uranium resources represent an energy source larger than coal ▪ Near elimination of fissile material from waste. ▪ Reprocessing and recycle also enables use of Thorium which is abundant in India ▪ Thorium advantages : high burn up, reduced minor actinides production, higher safety margins, higher proliferation resistance etc. ▪ India has a unique opportunity here as eventually Thorium would assume importance worldwide ▪ Closed fuel cycle and reprocessing also help in reducing the nuclear waste burden and radio-toxicity of finally disposed HLW.
Steps in Back End Fuel cycle: Closed fuel cycle • Under water cooling of spent nuclear fuel in spent fuel pool at reactor site to reduce decay heat and specific activity of spent fuel before taking up for reprocessing • Transportation of spent fuel from reactor site to reprocessing site • Reprocessing of spent nuclear fuel for recovery of fissile and fertile material • Fuel re-fabrication from the recovered fissile and fertile material • HLW management before final disposal into deep geological repositories and management of solid, liquid and gaseous waste for final disposal
Strategy of spent fuel management in India Spent fuel from Reprocessing of U & Pu product for nuclear reactor fuel spent fuel recycle /reuse storage pond Hull waste Recovery of Cs 137 , Sr 90 , Ru 106 disposal etc for societal benefits HLLW treatment ILLW treatment and disposal P&T of MAs in FBR / ADS HLW to Interim storage and finally to Deep Repository
High Level Liquid Waste Treatment Recovery of useful fission products and minor actinides before waste immobilization. ▪ Successful demonstration of actinides partitioning from HLW done at plant scale. ▪ Recoveries better than 99.9 % has been demonstrated Immobilization of waste oxides in stable and inert solid matrices. ▪ Partitioning permits use of tailor made matrices for conditioning selected waste streams in parallel with the established vitreous matrices. Interim retrievable storage of the conditioned waste under continuous cooling.
▪ High capacity melter for vitrification ▪ Advanced melters like cold crucible are being implemented for high burn up fuel. ▪ Studies for deep geological repositories in progress. Volume of High Level Vitrified waste generated for power consumption of an average family for entire life Volume of waste if actinide is also separated from HLW
Adopting closed fuel cycle also reduces nuclear waste burden. Natural decay of spent fuel radiotoxicity Radiotoxicity of spent fuel is dominated by : FPs for first 100 years. 200,000 years subsequently, Pu (>90%) After Pu removal Minor Actinides specially Am (~ 9% ) 300 years With early introduction of fast reactors using (U+Pu+Am) based fuel, long term raditoxicity of nuclear waste will be reduced.
India ’ s Five decades of experience in Reprocessing of PHWR Spent Fuel • Enormous experience of 50 years of PHWR spent fuel reprocessing • Product recoveries better than 99 % • Decontamination Factors of the order of 10 7 • Environmental discharges are quite below the regulatory limits Concept of Integrated Nuclear Recycle Plants
Integrated Recycle Facility • Works on solid-in solid-out concept and includes reprocessing facility, waste management facility and fuel fabrication facility • Designed for Thermal Reactor spent fuel management • Reprocessed Uranium and Plutonium from these plants will be supplied for next generation reactors like FRs and Advanced Heavy Water Reactor
Inputs & Outputs Inactive Spent Fuel Chemical Plant inputs Gaseous /Liquid Discharge (As Low As Reasonably U & Pu Achievable) MOX fuel IRF Short Lived Waste Products Interim For Disposal Cs 137, Sr90, Actinides Storage Compacted Hull Vitrified Waste Non Hull Alpha Waste Canisters In Canisters In Air Products In Shielded Cells Shielded Vault Cooled Vault Long Term Storage
Benefits of Integrated management & responsibility for Back end fuel cycle activities • Standardization in all stages, from design to commissioning • Minimise duplication of systems/ equipment • Optimised man /material movement. • Reduced Capital and O&M Cost
Strategies for U & Pu utilization RU RU Pu & RU Fast Breeder Fast Breeder Pu & RU Surplus Pu Reactors PHWR Reactor Capacity (Initial Phase) Expansion Pu Fast Breeder Surplus Pu Reactors 233 U for Third Stage (Final Phase) Thorium
India: Reprocessing of Thorium Based Fuel • Thoria based fuel: Third stage of Indian Nuclear Three Stage Program • A Pilot plant and an engineering demonstration facility for reprocessing of Thoria based fuel • Successfully demonstrated processing of Thoria bundles irradiated in PHWRs and utilization of U 233 in R&D facilities.
Interfaces between back end cycle activities • Reactor and spent fuel storage and Transportation : – Extent of irradiation in nuclear reactor and decay heat of spent fuel at the time of discharge governs spent fuel storage/cooling time – Spent fuel storage capacity and design for decay heat removal – Requirement of Away From Reactor storage facilities – Consideration of safety requirements during design, construction and operation of transportation system like cask design for handling activity, decay heat and Physical Protection requirements during transportation etc
Interfaces between back end cycle activities • Issues in Storage and Reprocessing : – Storage period governs spent fuel specific activity – Economical effects due to spent fuel specific activity on back end activities e. g. shielding requirements, operating cost, waste generation etc. – Management of split pins/failed fuel
Interfaces between back end cycle activities • Reprocessing steps and End use of product: – End use of product governs the extent of product specifications – Minor actinides to be burnt in FBRs or ADSS, – Management of additional radioactive waste like spent organic, resins and other alpha waste • Partitioning & Transmutation and waste management: – Recovery of fission products like Cs 137 , Sr 90 , Ru 106 for societal benefits – Reduced heat load and Radio-toxicity of waste by separation of actinides – Use of actinides as fuel in FRs or ADSS as fuel
Information management & Knowledge management – Codes, Standards, Manuals are available on Regulatory body Network sites – Technical information regarding various R&D activities available on closed network system Information Gateways / Data storage facilities – Periodic reports and information regarding annual meetings are available and preserved – Data and knowledge preservation in digital format – Classified documents preservation under access control in hard copies as well as digital format
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