back end fuel cycle: indian scenario · features of closed fuel cycle with reprocessing and recycle...
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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 CycleVienna, 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 approvedand 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 ProgramThe goal of three stage Indian nuclear power programme is long term resource sustainability
www.indiaatcop22.orgAdvanced Heavy Water Reactor (AHWR)
Fast Breeder Reactor540 MW Pressurized Heavy Water reactor (PHWR)
Fuel cycle options
Fuel
Fissile + Fertile
Fissile partly spent
Fertile partly converted
Spent Fuel cooling & final disposal in
Geological Repository
Open or Once Through Fuel Cycle
Huge energy potential !!
Nuclear Reactor
Fuel cycle options
Closed Fuel Cycle
Fuel
Fissile + Fertile
Fissile partly spent
Fertile partly converted
Reprocessing
Fertile + Fissile
HLW to Interim storage and finally to Deep Repository
Fuel Fabrication
Huge energy potential !!
Nuclear Reactor
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 nuclear reactor fuel
storage pond
Reprocessing of spent fuel
HLLW treatment
U & Pu product for recycle /reuse
Hull waste disposal
Recovery of Cs137, Sr90, Ru106
etc for societal benefits
P&T of MAs in FBR / ADS
HLW to Interim storage and finally
to Deep Repository
ILLW treatment and disposal
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.
Radiotoxicity of spent fuel is dominated by :
FPs for first 100 years.
subsequently, Pu (>90%)
After Pu removal
Minor Actinides specially Am (~ 9%)
Natural decay of spent fuel radiotoxicity
With early introduction of fast reactors using (U+Pu+Am) based fuel, long term raditoxicity of nuclear wastewill be reduced.
200,000 years
300 years
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 107
• 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 reprocessingfacility, waste management facility and fuel fabrication facility
• Designed for Thermal Reactor spent fuel management
• Reprocessed Uranium and Plutonium from these plants will besupplied for next generation reactors like FRs and Advanced HeavyWater Reactor
Inputs & Outputs
IRF
Plant inputs
InterimStorage
Short Lived Waste Products For Disposal
U & PuMOX fuel
Cs 137, Sr90, Actinides
Vitrified Waste Canisters In Air
Cooled Vault
Compacted Hull Canisters In
Shielded Vault
Non Hull Alpha Waste Products In Shielded Cells
Spent FuelInactive
Chemical
Gaseous /Liquid Discharge(As Low As Reasonably Achievable)
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
Fast BreederReactors
(Initial Phase)
Pu & RUPHWR
Pu & RU
Surplus Pu Fast BreederReactor Capacity
Expansion
Thorium
233U for Third Stage
Pu
Fast BreederReactors
(Final Phase)
RU
RU
Strategies for U & Pu utilization
Surplus Pu
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 ofThoria based fuel
• Successfully demonstrated processing of Thoria bundles irradiated inPHWRs and utilization of U233 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 Cs137, Sr90, Ru106 for societalbenefits
– Reduced heat load and Radio-toxicity of waste by separation ofactinides
– Use of actinides as fuel in FRs or ADSS as fuel
Information management & Knowledge management
– Codes, Standards, Manuals are available on Regulatory body Networksites
– Technical information regarding various R&D activities available onclosed network system Information Gateways / Data storage facilities
– Periodic reports and information regarding annual meetings areavailable and preserved
– Data and knowledge preservation in digital format
– Classified documents preservation under access control in hard copiesas well as digital format
– Framing of regulatory guidelines as well as ensuring safety of public
and environment during design, construction, commissioning,
operation and decommissioning of the facility.
– Ensuring proper knowledge management that includes new
knowledge creation as well as knowledge sharing, storage and
refinement.
Role of regulatory body
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REGULATORY ASPECTS
Initial Safety related documents
DBR/PSAR
Detailed Plant level Review
Detailed safety Review following set guidelines
Revision and approved copy in practice in routine practice
Tech Specification & SOPs
O&M FACILITIES SAFETY
Annual RIT Review
Licensing & Relicensing Procedures
Authorization/ Re-authorization of
facilities on regular interval
Conclusion
• In closed fuel cycle, a significant fraction of the energy input would come
from reprocessed fissile & fertile material for recycle.
• Fuel cycle with reprocessing and P&T options for recycling of actinides,
recovery of important fission products
• Steps towards Information management and Knowledge management
• Integrated Nuclear Recycle Plant is one step taken for the integrated
approach in the back end fuel cycle.
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