Flue gas desulfurization (FGD) systems continue to have deposits formed on internal surfaces of the materials of which the FGD systems are fabricated. These compounds contribute to crevice corrosion of the alloys of which some of the FGD systems are made. In the process of performing the failure analysis of the FGD fabrication materials, new compounds were discovered. This paper discusses two corrosion failure analysis case histories and the new compounds that were discovered and the chemical environment in which they were discovered.
Keywords: calcium sufide, syn-gypsum, calcium sulfite hemihydrite, flue gas desulfurization, failure analysis