SO3 SEPARATING AND REMOVING EQUIPMENT FOR FLUE GAS

摘要

A sulfur trioxide (SO 3) separating and removing apparatus (10) is capable of lowering the density of SO 3contained in flue gas and separating and removing SO 3component from the flue gas at the inlet of a wet type desulfurization device (7). The flue gas is cooled so that sulfur trioxide reacts with moisture in the flue gas to produce sulfuric acid, which is condensed out. A sulfur trioxide (SO 3) separating and removing apparatus (10) has a sodium carbonate feeding device (20), for feeding sodium carbonate to the flue gas, installed at the outlet of a boiler (1), comprising a heat exchanger of shell and tube type. The flue gas is passed through a shell side and boiler feed water is passed through the tube side to cool the flue gas to the dew point of sulfuric acid (H 2SO 4) gas, or below, to react the SO 3gas with moisture contained in the flue gas according to the lowering of temperature, so as to produce H 2SO 4gas ,which is condensed and adhered onto the surface of tubes. The liquid H 2SO 4adhered onto the surface of the tubes is washed out by using water to remove the SO 3component from the flue gas.