Diagnostic for Rapid Characterization of TRISO Fuel Pellets Using Soft X-Rays

In the coming generation of Very High Temperature Reactors (VHTRs), nuclear fuel is encapsulated into billions of small, tri-structural isotropic (TRISO) fuel pellets. To facilitate the licensing and economic competitiveness of the anticipated future generation of VHTRs, improved quality control of TRISO pellets (less than one bad coating in 105) is desired. Presently, characterization of fuel pellets is primarily performed on a sampling basis using slow and laborious methods. As billions of TRISO fuel pellets are used in a reactor core, it is desirable to develop a fast (> 200 pellet/sec), automatic, non-destructive method of detecting TRISO pellet defects and rejecting defective pellets. FAR-TECH, Inc. proposes to collaborate with researchers at the University of California in San Diego (UCSD) to develop a technique for X-ray diagnosis of TRISO pellets with the goal of automated fault detection at a throughput of 200 pellets per second. Such a system would allow the inner TRISO layers, including the SiC layer, to be examined rapidly and non-destructively. Commercial Applications and Other Benefits: The ability to rapidly diagnose TRISO fuel pellets would allow all of the pellets going into a reactor to be tested, rather than just a random sample. This improvement in quality control could assist in the licensing process for future VHTRs.