Development of the UREX+2 Flowsheet—An Advanced Separations Process for Spent Fuel Processing

摘要

Advanced Fuel Cycle Initiative (AFCI) flowsheet studies for the development of the UREX+2 Flowsheet, an advanced separations process for spent fuel processing, have been in progress in the Radiochemical Engineering Development Center (REDC) at Oak Ridge National Laboratory (ORNL) and at other national laboratories for the last three years. The flowsheet, shown schematically in Fig. 1, enables the recovery of uranium, plutonium, and the minor actinides, neptunium, americium, and curium for recycle and the recovery of long-lived fission products (~(129)I,~(99)Tc) and high heat generators (~(137)Cs, ~(90)Sr) for improved waste management. Moreover, the process is designed for treatment of long-cooled ( > 30 years) spent fuel that now exists in the U.S., taking advantage of the smaller amounts of decay heat to reduce the number or process steps required. With appropriate blending of the spent fuels to be processed, the UREX+2 flowsheet can be applied to all types of oxide fuels, and, with special head-end preparation, to other fuel materials.