Control of Radiolytic Gases in Liners of Radioactive Zeolites

摘要

Early in the design evolution for the SDS demineralizer vessels (liners) at TMI-2, it was recognized that the production of gases due to the radiolytic decomposition of water in the liners would present a safety concern for in-plant storage, shipping, and disposal. Radiolytic gases were encountered during preparations to ship highly loaded zeolites to Pacific Northwest Laboratories (PNL) for vitrification R and D studies. A DOE-sponsored R and D program was initiated at Rockwell Hanford Operations and at Westinghouse Hanford Engineering Development Laboratories to define the optimum conditions for the use of an aluminum oxide coating with palladium-platinum as catalyst. A catalyst volume of 130 cc was effective in controlling and recombining H sub 2 /O sub 2 gases at test rates of 300 cc (STP) per hour. Placing the catalyst inside the 0.28 m exp 3 zeolite containers is performed remotely. Tests show the catalyst to be effective during both normal and upset conditions. (ERA citation 08:017816)