Nuclear Science


Used Nuclear Fuel Inventory Characterization

Used fuel sample

Used fuel sample being prepared for destructive radiochemical analysis for validation of nuclide inventory calculations.

Analysis of used fuel inventories and associated radiological characteristics is required for design and safety evaluations related to almost every aspect of the nuclear fuel cycle, from reactor analysis, used fuel handling and interim pool storage, to dry cask storage and final repository disposition. ORNL develops and maintains the ORIGEN code for used fuel analysis as part of the SCALE nuclear systems modeling and simulation system.

ORIGEN is a state-of-the-art isotope depletion and decay analysis code used internationally for safety analysis and licensing studies of used fuel facilities. ORIGEN tracks the time dependent concentrations of more than 2,200 individual isotopes, including heavy elements, fission products, and activation materials. Radiological properties including gamma, neutron, beta and alpha emissions and energy spectra, decay activities, and decay heat power are also calculated. Nuclear data are based on ENDF/B-VII, and cross section libraries are developed and distributed for analysis for all commercial reactor designs used worldwide. The code has been extensively validated using isotopic measurements from destructive radiochemical assay measurements of spent fuel and fuel assembly calorimeter measurements through international experimental programs supported by the Nuclear Regulatory Commission and the Department of Energy.

For More Information, Contact:

Used Fuel Systems Group Leader

John Scaglione


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