Abstract
The development of oxy-fuel combustion technology for coal-based power generation may produce combustion products different from those typically found in traditional boilers. In particular, the enrichment of CO2 and perhaps SO3 could alter the chemical equilibrium to favor the formation of certain carbonates and sulfates in the deposit. Higher concentrations of these gases would also increase the potential for condensation of carbonic and sulfuric acids in lower-temperature areas of the boiler. To address these concerns, B&W has instituted a comprehensive research program to better understand the effect of oxy-coal combustion on fireside corrosion. The scope of this program includes gas and deposit analyses of actual combustion products sampled from B&W's Clean Environment Development Facility (CEDF) during the oxy-coal combustion of three commercial coals. The sampling locations consist of regions representing the lower furnace, superheater bank, and pulverizer outlet. Following the gas and deposit analyses, a series of laboratory corrosion tests will be performed to expose candidate alloys and coatings to conditions simulating the oxy-coal combustion environments. The technical approaches and results of the fireside corrosion program obtained to date are discussed.
