Status of Transmutation Studies in a Fast Reactor at Jnc

This paper presents the status of studies on transmutation of minor actinides (MA) and long-lived fission products (LLFP) in a fast reactor at JNC, which includes four areas of work: (a) design studies, (b) nuclear data measurement and evaluation, (c) fuel fabrication and irradiation test, (d) strategy studies. It was found that the mixed hybrid MA-loading method, where Np nuclide is dispersed uniformly in the core and target subassemblies containing Am, Cm and rare earth nuclides are loaded into the radial blanket region, has a great potential to achieve effective transmutation of MA without serious drawbacks in terms of core performance. Fission cross section ratios of minor actinide nuclides (Np, Am, Am, Am, etc.) in the fast and epithermal neutron energy region have been measured to evaluate the accuracy of MA nuclear data. As for fabrication and investigation of irradiation behaviour of MOX containing MA, the systematic program has been planned. The irradiation test of Npand Am-contained MOX fuel is planned in JOYO. In step with the JOYO MKIII schedule, the irradiation test will be initiated from around 2003.