Study on the Removal Characteristics of SO3 Acid Mist during the Condensation of Wet Flue Gas

This work reported the removal characteristics of SO3 acid mist during the condensation of wet flue gas through both simulations and experiments. A model suitable for the removal of SO3 acid mist was established, and the results of simulation showed that the mean diameters of acid mist would rapidly increase to microns. The growth rate of the size and removal efficiency gradually decreased along the flue gas flow direction. The influence of temperature drop, relative humidity of inlet flue gas, and trapping area on the SO3 removal performance was experimentally studied. The results revealed that the emission of SO3 can be significantly decreased via increasing these three parameters. The removal efficiency at first increased and then decreased when the SO3 concentration increased. When the SO3 concentration was 60 mg/m(3), the relative humidity was 100%, and the temperature drop was 32.5 degrees C; the largest removal efficiency of 43.3% could be obtained. However, under isothermal conditions, the SO3 removal efficiency also reached more than 20%, indicating the possibility of changing the condenser structure to strengthen the removal.