Corroded Pipes from Gas Generating Plant
After four months at a temperature of 400 to 5000 C, pipes at a gas generating plant were so heavily eroded they had to be replaced. Three sections of pipe, from different locations, were analyzed to determine whether mechanical wear or corrosion caused the damage. Samples of corrosion product from each pipe section were analyzed for carbon, sulfur, and iron and were found to consist mainly of iron sulfide mixed with soot and rust. The damage resulted from a high content of hydrogen sulfide in the gas (6% CO2, 20% CO, 8 to 12% H2, 0.5 to 1.5% CH4, remainder N2). To process the coal in question, the pipes material should be a heat-resistant steel that contains more chromium and has greater resistance to hydrogen sulfide.