An Investigation of the use of Ceramic Microencapsulated Fuel for Transuranic Waste Recycling in Pressurized Water Reactors

Presented is an investigation of the utilization of Tristructural-Isotropic (TRISO) particle-based fuel designs for the recycling of Plutonium/Neptunium (Pu/Np) Transuranic (TRU) isotopes in typical Westinghouse four-loop pressurized water reactors. Though numerous studies have evaluated the recycling of TRU isotopes in light water reactors (LWRs), this work differentiates itself by employing Pu/Np loaded TRISO particles embedded within a SiC matrix and formed into pellets that can be loaded into standard 17x17 fuel element cladding. This approach provides the capability of Pu/Np recycling, and by virtue of the TRISO particle design, will allow for greater burnup of Pu/Np material and improved fuel reliability. In this study, a variety of assembly layouts and core loading patterns were analyzed to demonstrate the feasibility of Pu/Np loaded TRISO fuel. The assembly and core designs herein reported are not fully optimized, and require fine-tuning to flatten power peaks, however, the progress achieved thus far strongly supports the conclusion that with further rod/assembly/core loading and placement optimization, Pu/Np loaded TRISO fuel and core designs that are capable of balancing Pu/Np production/destruction can be designed within the standard constraints for thermal and reactivity performance in PWRs.