The corrosion risks in a wet flue gas desulphurization system
environment are reported. Uniform and localized corrosion
resistance of different stainless steels is studied by electrochemical
tests. The effects of chloride content, fluoride content, pH and
temperature on corrosion resistance are discussed. The results show
that duplex UNS S32205 or superduplex UNS S32520 grades
are prime substitutes for austenitic 317LNM or super austenitic like
UNS S34565 grades in many aggressive environments. The life
cycle costs of scrubbers constructed of stainless steels plates or clad
plates are compared. The excellent corrosion resistance of duplex
and superduplex stainless steels, combined with their increased
mechanical properties and moderate alloy cost afford very cost
effective solutions for wet flue gas desulphurization.