Operation of a radiochemical uranium nitrate solidification facility

A unique radiochemical processing facility at Oak Ridge National Laboratory has been operated to convert approx.1000 kg of highly fissile and radioactive uranium (containing approx.76% /sup 235/U, approx. =10% /sup 233/U, and approx.140 ppm /sup 232/U) in the form of a nitrate solution to a packaged solid oxide that is suitable for safe storage. The project was called the Consolidated Edison Uranium Solidification Program (CEUSP) because the uranium was the product of an experimental power reactor fuel, consisting of fully enriched /sup 235/U and thorium, which was irradiated in the Indian Point-1 Reactor in the early 1960s. The irradiated fuel was reprocessed at the Nuclear Fuel Services's plant at West Valley, New York in late 1968, and the uranium product solution was transported to Oak Ridge and stored. The material was originally considered quite valuable, but the intense radiation associated with the decay of /sup 232/U precluded further use. Several options were explored to solidify the material for safe storage. This paper will describe the design and development of the solidification process and review the operation history.