Material attractiveness evaluation of actinides in Pyroprocessing Facility for partitioning and transmutation cycle

Oizumi, Akito   ; Sagara, Hiroshi*

Research and development of partitioning and transmutation (P&T) cycle with accelerator-drive systems (ADSs) transmuting minor actinides (MAs) separated from the commercial cycles has been continuously conducted to reduce the high-level radioactive waste (HLW) contained in spent fuel discharged from nuclear power plants. The Japan Atomic Energy Agency has proposed a pyrochemical process for reprocessing ADS spent fuel with high decay heat and radioactivity due to the large amount of MA. Since the chemical form and composition of the fuels are different from those of the current commercial cycles, it is necessary to examine the inspection goal of the safeguards (SGs) and the design level of physical protections (PPs) which are required for the P&T cycle. In this study, the material attractiveness was evaluated assuming the diversion of the Cd cathode and the nitride powder from the pyroprocessing in terms of non-proliferation. Additionally, they were compared with the material attractiveness of the MOX fuel assemblies (fresh and spent fuels) for a conventional boiling water reactor (BWR). The Cd cathode used to recover actinides from ADS spent fuel by molten salt electrolysis in the pyroprocessing facility of P&T cycle was less attractive than the MOX fuel assembly for the BWR because the Cd cathode included Pu having high decay heat. The nitride powder electrorefined from the ADS spent fuel was also less attractiveness than the MOX fuel assembly for the BWR because of the same reasons of the Cd cathode.