Single-Step Process to Treat the High Chloride Pu Inventory at the Plutonium Finishing Plant (PFP)

摘要

The Plutonium Finishing Plant (PFP), operated by Fluor Hanford identified that up to 1000 items in their inventory contained high concentrations of chloride salts. This is problematic in that some of these salts are volatile at stabilization temperatures. At temperature 950 deg.C the molten salt is volatile and very corrosive to the furnace and off-gas system. Early testing at PFP indicated that the salt would deposit and plug the off-gas line. After stabilization, a sample of the material is processed through a Loss-on-Ignition (LOI) test. This test is intended to demonstrate that the stabilized material has 0.5% moisture, which is required to meet Department of Energy (DOE) Order 3013 requirements. Pacific Northwest National Laboratory (PNNL) identified a potential process whereby the volatile nature of the salts could be used to potentially separate the salts from the plutonium oxide. After identification of this potential process, the Nuclear Material Focus Area acted quickly and as a result, in July 2001, PNNL was funded to design, build, and test a simple proof-of-principle system.