DEVELOPMENT AND OPERATION OF THE CONVERSION/SOLIDIFICATION PROCESS FOR THE CEUSP PROJECT.

A uranium nitrate solution from reprocessing irradiated nuclear fuel of the Atomic Energy Commission was solidified for safe long-term storage by the Consolidated Edison Uranium Solidification Program (CEUSP). The key process steps of the program includes the following: (1) a batch evaporation to concentrate the uranium-cadmium-gadolinium nitrate solution to slightly less than the saturation concentration; (2) the use of formaldehyde in the evaporator to destroy nitric acid so that crystallization of the nitrate salts due to supersaturation would not occur; (3) the use of an in-situ thermal denitration process to convert uranium, cadmium, and gadolinium to the oxide form inside the storage cans; (4) the use of remotely operated equipment to weld lids onto the storage cans; (5) encapsulation of each can within a crimp-sealed, secondary containment canister; and (6) transfer of the finished packages to a shielded storage well.