Neutronics feasibility of simple and dry recycling technologies for a self-sustainable breed-and-burn fast reactor

This paper is concerned with the neutronics analysis of extremely simplified recycling technologies of spent fuels in a small breed-and-burn fast reactor (B&BR). The discharged fuels of the first generation B&BR, which achieved an average burnup of 160 GWd/MTHM, were used to construct a second generation B&BR core. Two types of high proliferation resistant recycling technologies, melt refining and the newly suggested super-simplified melt and treatment, were applied to process and treat the discharged fuels. Because the burnup profile of discharged fuels varies largely depending on its position in the core, the recycling of the discharged fuels was also carried out by grouping them into recycling regions including 1, 3, and 6 recycling regions. In this study, the core performance of the 2nd generation B&BR loaded with the recycled fuel, which was produced by different recycling technologies and recycling regions, was analyzed and compared. An optimum fuel loading scheme was also adopted to maximize the performance of the 2nd generation B&BR in terms of the burnup reactivity change, core lifetime, and power profiles.