J. Bauer, M.C. Galetz, M. Schütze
It has become well-known that heavy metals have bad effects on high temperature corrosion of boiler tubes in waste-to-energy plants, but the detailed behavior is still not clear. In this work, behavior of heavy metals was investigated by analyzing ash deposits in an actual plant and conducting corrosion tests with artificial ashes based on the actual ash compositions. Heavy metals condense to the tube side of the ash deposits. This leads to depression of melting points of ash deposits and condensation of Cl on tube surface. Therefore heavy metals cause deterioration of corrosive environment. Especially, Cu has a strong impact on corrosion. Alloys containing Mo have some resistance to the corrosion.