A Physics Study on Thorium Fuel Recycling in a CANDU Reactor Using Dry Process Technology

Dry process fuel technology has high proliferation resistance, which is one of the important goals of the Generation-IV nuclear energy system developments. It is expected that dry process fuel technology can be applied not only to existing but also to future nuclear systems. In this study, the homogeneous ThO2-UO2 fuel cycle and the heterogeneous ThO2-DUPIC fuel cycle options of a Canada deuterium uranium (CANDU) reactor were assessed, which included a neutronic feasibility analysis of recycling spent fuels. Parametric calculations were also performed for reactivity coefficients and isotopic content changes for various initial fuel conditions. The results of the physics calculations have shown that it is feasible to recycle the thorium fuel through the dry process option in the CANDU reactor, which in turn significantly improves natural uranium savings and diminishes spent fuel. However, further investigation of the dry process option, which is technically and economically feasible for thorium-abundant dioxide fuel, is required.