Year
2014
Abstract
Successful deployment of fast reactors crucially depends on advanced fuel development to provide economic solutions to energy problems while keeping the reactor inherently pro- liferation resistant and safe. A new type of composite fuels (CF) has been proposed as a potentially viable solution to the economics-nonproliferation-safety problems, and this paper will focus on discussion of non-proliferation aspect of these fuels. The CF consists of granules of oxide and metallic fuel intimately mixed at the microscopic level and held together by a porous inert metal frame. Previous research by Savchenko et al. has es- tablished the manufacturability of these fuels and demonstrated their desirable material characteristics, including good irradiation resistance. While their work was limited to a single combination of compounds, this project builds on the initial results to screen multiple combinations and determine how the performance of ultra-high burnup fast re- actors can be enhanced. Since proliferation is a major concern in these long-lived cores, innovative design approaches alongside safeguard methods are needed. Considering these issues from the inception point of novel reactor concepts has the potential to provide more practical and economical solutions to meet these challenges. Through its micro- scopic intermixing of fissile (PuO2) and fertile (U-metal) spherules, the CF is already less susceptible to diversion than fuels in more traditional fast reactors relying on a blanket region. Work is currently being undertaken in neutronics and material properties to un- derstand the fuel performance issues and to estimate the amount of denaturation in the generated plutonium and the emitted dose of the fission products, which directly influences the ease of handling and reprocessing. A virtual model of the CF microstructure is under study for further analysis by MCNP6. Comparison of the results directly to those of more traditional types of fuel will be presented to demonstrate the viability of non-proliferation by design approaches and the potential of the CF to outperform their counterparts. Al- ternative compositions of the CF that enhance their proliferation resistance will also be discussed.