Evaluation of PFP Furnace Systems for Thermal Stabilization of Washed High Chloride Plutonium Oxide Items

Fischer, Christopher M. ; Elmore, Monte R. ; Schmidt, Andrew J. ; Gerber, Mark A. ; Muzatko, Danielle S. ; Gano, Susan R. ; Thornton, Brenda M.

Pacific Northwest National Laboratory (U.S.)

关键词: Corrosion;    Radioactive Waste Processing Chlorides, Chloride Salts, Corrosion, Corrosion Rate, Doe-Std-30313-2000, Furnace, High Chloride Plutonium Oxides, Hanford, Hcp, Material Balance, Materials Testing, Muffle Furnace, Nuclear Materials Stabilization Project, Plutonium Finishing Plant, Pfp, Plutonium, Plutonium Oxides, Plutonium Scrap, Offgas, Storage, Thermal Stabilization;    Chlorides;    Corrosive Effects;    Stabilization;   

DOI  :  10.2172/15010232
RP-ID  :  PNNL-14260
RP-ID  :  AC05-76RL01830
RP-ID  :  15010232

美国|英语

来源: UNT Digital Library

【 摘 要 】

High chloride content plutonium (HCP) oxides are impure plutonium oxide scrap which contains NaCl, KCl, MgCl2 and/or CaCl2 salts at potentially high concentrations and must be stabilized at 950 C per the DOE Standard, DOE-STD-3013-2000. The chlorides pose challenges to stabilization because volatile chloride salts and decomposition products can corrode furnace heating elements and downstream ventilation components. A high-temperature furnace (same make and model as used at the RMC at Plutonium Finishing Plant) and the associated offgas system were set up at PNNL to identify system vulnerabilities and to investigate alternative materials and operating conditions that would mitigate any corrosion and plugging of furnace and offgas components. The key areas of interest for this testing were the furnace heating elements, the offgas line located inside the furnace, the offgas line between the furnace and the filter/knockout pot, the filter/knockout pot, the sample boat, and corrosion coupons to evaluate alternative materials of construction. The evaluation was conducted by charging the furnace with CeO2 that had been impregnated with a mixture of chloride salts (selected to represent the expected residual chloride salt level in washed high chloride items) and heated in the furnace in accordance with the temperature ramp rates and hold times used at PFP.