PROCESS FOR CLEANING FLUE GAS

摘要

A flue gas containing SOx, NOx and O2 is washed with an aqueous alkaline solution containing an NOx removal catalyst to form the salts selected from a dithionate, a sulfate and an imidobissulfate. The salts are crystallized, separated and heated for pyrolysis by a pneumatic conveying pyrolysis unit whereby a gas containing higher concentration of SO2 is obtained. The gas is fed into the aqueous alkaline solution together with the flue gas so as to improve the efficiency of the process.