Materials Evaluation in the WERF (Waste Experimental Reduction Facility) Low-Level Radioactive Waste Incinerator off-Gas System

摘要

Performances of alloys in a low-level radioactive, combustible waste incinerator were evaluated. Test coupons and an extracted heat exchanger tube were examined to provide information on alloy behavior in the off-gas system of this facility. Type 316 stainless steel, the alloy of which the heat exchanger is constructed, was most extensively examined. Coupons exposed upstream of the heat exchanger exhibited high temperature corrosion rates of /approximately/100 mpy (incinerator operation time). The rate observed from the heat exchanger tube was lower, /approximately/25 mpy. A 10 year lifetime would be expected based upon this mode of attack and continued similar operating parameters and waste composition. Other alloys were tested to identify potential replacement candidates. Alloys displaying lower metal loss rates at the location upstream of the heat exchanger included HDA 8727 (7 mpy), Alloy 800H (37 mpy), Haynes 230 (50 mpy), and Type 310 stainless steel (63 mpy). The relatively long term exposures (spanning over 4250 hrs of operation) and controlled waste composition makes this information pertinent to the waste incineration community as well as the WERF program. 15 refs., 18 figs., 11 tabs. (ERA citation 14:007441)