Minor Actinide Transmutation in BWR Cores for Multi-recycle Operation with Less Minor Actinide-to-Fissile Plutonium Amount Ratio

Minor actinide (MA) transmutation performances were evaluated for BWR cores with mixed oxide (MOX) fuels of various hydrogen-to-heavy metal atom number ratios (H/HM) to decrease the work for high-level radioactive wastes (HLW) management. One effective approach to increase the MA transmutation ratio is a multi-recycle core of MOX fuel with MA. The decrease of the MA-to-fissile Plutonium (Puf) amount ratio makes it possible to recycle MA without additional plutonium (Pu) obtained from reprocessing of LWR fuel. For this purpose, a T-ratio, which is the MA-to-Puf amount ratio change during burnup, of less than unity is required, and H/HM must be less than 3 when MA enrichment is more than 2wt%. For multi-recycle cores with the H/HM of 3 and the initial MA enrichment of 5wt%, more than 50% of MA load initially can be transmuted by the third recycle.