New technology for purification of the flue gas from sulfur dioxide

A new type of installation for SO2 removal from flue gas, producing high quality gypsum, is described. It ensures conditions at which the absorption process is practically gas side controlled with elimination of the resistance in the liquid phase boundary layer between gas and liquid and between the liquid and solid CaCO3 used as absorbent. This gives the possibility to calculate the absorption using data from literature, which eliminates the necessity of performing experiments for the given system and absorber construction. The new installation ensures high absorption degree, more than 99%, and provides optimal conditions for oxidation of the CaSO3 to gypsum, small height of the packing of the absorbers and low pressure drop. The installation is intended for removal of SO2 from the flue gases from small and middle capacity boilers, but with small changes can be used for big boilers too. Key words: SO2 removal, flue gas, new type of installation, slurry, gypsum, absorption degree, gas side controlled absorption, packed bed column, Holpack packing, small and middle capacity boilers