Design study of accelerator-driven system for minor actinide transmutation in JAEA

Tsujimoto, Kazufumi ; Nishihara, Kenji  ; Takei, Hayanori   ; Sugawara, Takanori  ; Iwamoto, Hiroki   ; Sasa, Toshinobu   

The Japan Atomic Energy Agency (JAEA) has been conducting the research and development (R&D) on accelerator-driven system (ADS) as a dedicated transmutation system of long-lived radioactive nuclides. The ADS proposed by JAEA is a lead-bismuth eutectic (LBE) cooled fast subcritical reactor with thermal output of 800 MW. For ADS to play important roles in the nuclear fuel cycle, several critical issues have to be resolved. The critical issue in the design of the ADS is the engineering feasibility of the beam window for the high power spallation target. Although a feasible concept of the beam window for the ADS was proposed in our previous work. To mitigate the thermal load of the beam window not only in the normal operation but also in the transient situations, the R&D for the mechanism of reactivity adjustment and the accelerator design have been performed in JAEA.