The chimney without installing gas-gas heater(GGH) is simply called wet chimney.Because of low temperature of the discharged flue gas

and a large amount of the acidic condensated water

the corrosion problems occurred in wet chimneys soon after the said chimneys being put into operation.For this

the causes leading to corrosion in wet chimneys have been analysed

and the anti-corrosion technologies used for wet chimneys and their effectiveness being presented.The selection principles for anti-corrosion technologies in wet chimneys being summarized up.On the basis of materical test and practical results in operation

it is recommended to use a new anti-corrosion technology of GD-APC mixed polymerization for anti-corrosion in wet chimneys being newly constructed and for anti-corrosion of old chimneys to be retrofitted.