CORROSION RESISTANCE OF DUPLEX AND 4-6 MO-CONTAINING STAINLESS STEELS IN FGD SCRUBBER ABSORBER SLURRY ENVIRONMENTS

摘要

Field tests using specimen racks were performed in six operating flue gas desulfurization (FGD) scrubber absorbers to determine the corrosion resistance of a 22Cr-5Ni duplex alloy, a 4% Mo-containing (Type 317LMN) stainless steel, and a 6% Mo-containing stainless steel. Type 316 stainless steel and alloy C-276 specimens served as highly- susceptible and highly-resistant controls, respectively. The chloride levels in the six absorber slurry environments ranged from -9000 to -70,000 ppm. The pH was typically -5.5 with the slurry temperature in the 120 - 154℉ (-49-68°C) range. Duplicate specimens were tested with "loose" and "tight" crevices for two exposure periods.