Conceptual core design of the breeder type FLWR using recovered uranium as blanket fuel

Uchikawa, Sadao; Nakano, Yoshihiro ; Okubo, Tsutomu; Kobayashi, Noboru

The present study deals with the potential effects of utilization of uranium recovered from LWR spent fuels as the axial blanket fuels in the core of the breeder type FLWR, which is characterized by the five-layer double-flat-core structure. Design studies shows that the adoption of recovered UO blanket can reduce the required plutonium inventory to attain the same core performances as the previous core design of depleted uranium blankets. Furthermore, the utilization of re-enriched recovered uranium with U enrichment of about 5wt% as the internal blanket fuel is evaluated to have a potential of a conversion ratio of 1.1. The core design with reduced plutonium inventory and high conversion ratio can contribute to realize a smooth and speedy transition from the LWR fuel cycle to the sustainable fuel cycle, as a core design for the transitioning period, during which a sufficient amount of uranium recovered from LWR spent fuels is available as resources.