A conceptual design study of proliferation-resistant PWR fuel using reprocessed uranium

A conceptual design study was carried out to enhance proliferation-resistant nature of current light water reactor fuels. Main features of the proliferation-resistant fuel design are adoption of alloy instead of oxide and utilization of enriched reprocessed uranium (∼10 wt% 235U). Major dimensions of the fuel assembly were not changed because of thermal-hydraulic considerations and back-fittability to current PWRs. Its smaller 238U inventory reduces generation of plutonium and 236U in the reprocessed uranium promotes generation of 238Pu that has large decay heat. The assembly calculation results of the fuel indicated that the fuel has good proliferation-resistant nature in the viewpoint of decreased plutonium generation, worse plutonium composition and increased decay heat. Neutronic analyses of an equilibrium core loaded with the proliferation-resistant fuels were carried out and calculation results indicate that variations of major core safety parameters are not very large. Therefore, basic feasibility of the proliferation-resistant fuel design using reprocessed uranium was confirmed in the course of this study.