Layer thickness evaluation for transuranic transmutation in a fusion–fission system

Highlights: • Layer thickness for transmutation in a fusion–fission system was evaluated. • The calculations were performed using MONTEBURNS code. • The results indicate the best thickness and volume ratio to induce transmutation. - Abstract: Layer thickness for transuranic transmutation in a fusion–fission system was evaluated using two different ways. In the first one, transmutation layer thicknesses were designed maintaining the fuel rod radius constant; in the second part, while the transmutation layer thickness increases, the fuel rod radius decreases maintaining k_s (source-multiplication factor) ≈0.95. Spent fuel reprocessed by UREX+ method and then spiked with thorium and uranium composes the transmutation layer. The calculations were performed using MONTEBURNS code (MCNP5 and ORIGEN 2.1). The results indicate the best thickness and the volume ratio between the coolant and the fuel composition to induce transmutation