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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Leading the charge: INL’s role in advancing HALEU production
Idaho National Laboratory is playing a key role in helping the U.S. Department of Energy meet near-term needs by recovering HALEU from federal inventories, providing critical support to help lay the foundation for a future commercial HALEU supply chain. INL also supports coordination of broader DOE efforts, from material recovery at the Savannah River Site in South Carolina to commercial enrichment initiatives.
John C. Lee, Sin Tao Hsue
Nuclear Technology | Volume 76 | Number 2 | February 1987 | Pages 203-208
Technical Paper | Fuel Cycle | doi.org/10.13182/NT87-A33874
Articles are hosted by Taylor and Francis Online.
Based on a simplified solution of the balance equations for concentration of uranium and plutonium isotopes and a set of two-group microscopic cross sections, isotopic ratios, 235U/U, Pu/U, and 239Pu/235U, are calculated as a function of fuel burnup for pressurized water reactor spent fuel. The two-group cross sections for 235U, 238U, 239Pu, and water are collapsed into equivalent thermal-group constants, with the fast-to-thermal flux ratio obtained through a two-group criticality consideration. For this purpose, parasitic neutron captures are represented through a simple semiempirical relationship. The calculational model, incorporated as the BURN code, yields isotopic ratios that compare favorably with three major data sets from the ISTLIB data bank.
