Fissile utilization of uranium, thorium, and plutonium fuels for a 60 MWt block-type high-temperature gas-cooled reactor

High-temperature gas reactor (HTGR) is one of the Generation IV nuclear reactors currently undergoing rapid development in the world. The utilization of fissile material becomes an important parameter in HTGR technology because of the use of layered particle-type fuel that makes it challenging to reprocess. This research aims to compare and optimize the fissile utilization of HTGR 60 MWt using UO2, (Th-U)O-2, and (Pu-U)O-2. The utilization of fissile material on HTGR is being studied in this research by using the SRAC (Standard Reactor Analysis Code) version 2006 and the Japanese Evaluated Nuclear Data Library (JENDL) version 4.0. Parametric surveys are performed for important neutronic parameters, including analyzing the effects of fuel enrichment and the coated fuel particle (CFP) amount. Fissile materials are analyzed on a 1% to 20% enrichment level, and the CFP number is varied from 4470 to 26 830. The neutronic parameters taken into account are k-inf, conversion ratio (CR), the density of fissile and fertile material, and neutron energy spectrum. The results suggest that 11% of fuel enrichment and CFP number between 8950 and 11 180 are optimal for 60MWt HTGR. The highest fuel utilization level at the end of the reactor period was achieved by Pu-based fuel, with 81.6% of utilized fissile material.

Automated summary

This study aims to compare and optimize the fissile utilization of different materials in the high-temperature gas-cooled reactor (HTGR), finding that fuel enrichment at 11% and CFP number between 8950 and 11,180 are optimal. Pu-based fuel achieves the highest fuel utilization level, with 81.6% of utilized fissile material at the end of the reactor period.