Depending on the chemical make-up of the waste stream and operational param
eters, a variety of high temperature corrosive environments are generated i
n the incinerator. As corrosion of industrial equipments is essentially due
to high content of sulfur and chlorine in the combustion gas, this study i
s focused on the interpretation of degradations of pure iron in experimenta
l air environment containing 1000 ppm of HCl and 100 ppm of SO2. Thermochem
ical calculations were used to estimate the role of these corrosive element
s considering chemical potential diagrams and stability paths in pseudo-bin
ary diagrams involving iron and the corrosive atmosphere. The influence of
chlorine has been described by the "active corrosion" mechanism proposed by
Grabke and confirmed by our calculations. The role of sulfur has been poin
ted by its "cycle" leading to the formation of eutectic metallic tri-sulfat
es, promoting a liquid phase corrosion type in the range of the industrial
temperatures.