Fundamental Study of the NOXSO Combined NO/sub X//SO sub 2 Flue Gas Treatment Process: Corrosion and Its Prevention

摘要

The high temperature corrosion behavior (oxidation, sulfidation, and hot corrosion) of a number of Ni-base and Fe-base alloys has been discussed. Ni-base alloys are found to be incompatible with the compounds involved in the NOXSO Process regeneration reactions. Austenitic stainless steels are susceptible to sensitization and to a limited extent, hot corrosion. Type 446 ferritic stainless steel with high Cr content and no Ni performs satisfactorily under the service conditions. Improvement of high temperature corrosion resistance can be achieved by surface coatings such as aluminizing, chromizing, MCrAlY overlay coatings, or ceramic coatings. Aluminized 316L stainless steel has proven effective against the corrosion attack. Other base materials such as low alloy steels, low Cr-content ferritic stainless steels, or low carbon austenitic stainless steels may also be considered, provided good surface coatings are applied. 11 references, 8 figures, 9 tables. (ERA citation 09:043218)