Effective utilization of uranium and plutonium in LWR cores - plutonium utilization improvements in BWR cores

To determine effective utilization of plutonium in a mixed-oxide (MOX) core, which is defined as one in which all uranium fuels are replaced with MOX Fuel, the Nuclear Power Engineering Corporation has studied the high-moderation core (HMC), which reduces plutonium inventory, and the low-moderation core (LMC), which reduces the plutonium consumption ratio by increasing the fissile conversion ratio (FCR) (the ratio of residual fissile in discharged fuel to fissile inventory in loaded fuel). It has also evaluated the plutonium inventory savings of the HMC and the FCR increase of the LMC and compared with a reference MOX core, which is a full MOX core based on a 1350-MW(electric) advanced boiling water reactor. In this study, the so-called large square lattice core (LSLC) concept was developed as the LMC with as little plant system modification as possible. The hexagonal lattice core (HLC) concept was developed, which allows modification of the plant system for increasing FCR.