Flue gas of coal-fired power plant emissions containing mainly sulfur dioxide, sulfur trioxide, carbon dioxide, nitrogen oxides and some dust.In the catalytic particles such as dust, SO2 in the flue gas section will be converted to SO3.After a wet flue gas desulfurization, flue gas moisture content is relatively large, SO3 will be converted to sulfuric acid vapors .When the flue gas temperature below the dew point of the sulfuric acid vapor concentration of sulfuric acid droplets will condense and adhere to the inner surface of the chimney. Meanwhile, acid along the inner wall downstream process, some has been evaporated, resulting in the inner wall of condensate in the acid concentration increases. Chimney wall long soak in the acid state, cause cryogenic condensation corrosion.

SEPUNA preservative solutions provided can be greatly reduced due to the positive pressure acid on the inner wall of the chimney wall corrosion, greatly extend the service life and maintenance cycle chimney.