Radiation and decay heat analysis of the Advanced Voloxidation process

KAERI has been developing a voloxidation process as a head-end process of pyroprocessing technology with INL(Idaho National Laboratory). It was named as the Advanced Voloxidation process by KAERI and INL. This report describes how much a radioactivity level can be reduced by this Advanced Voloxidation process. It also presents the element and radioactivity distributions of the nuclides in fresh spent PWR fuels, those after the advanced voloxidation process, and those of the gaseous fission products released from the advanced voloxidation process. Analysis was carried out for spent PWR fuels with a burn-up of 45,000 MWD/MTU and an initial enrichment of 4.5%. The calculated radioactivity reduction ratio of the spent PWR fuel meat by the Advanced Voloxidation process increases with the cooling time from 26% of discharge to 43-50% after 3 years cooling. The calculated decay heat reduction ratio increases with the cooling time from 39% of discharge up to 57% of 5 yrs cooling, and then decreases down to 40-50% after 10 yrs cooling. Cs is the most important element for off-gas treatment in view of radioactivity, decay heat, and mass aspects