DESULFURIZATION TREATMENT OF WASTE GAS

摘要

PURPOSE:To obtain gypsum with definite or more purity as a byproduct, by using cooled waste water from the cooling process of a waste gas in preparing an absorbing liquid by clarification treatment to reduce the amount of water to be used and to simplify the treatment of waste water after desulfurization treatment. CONSTITUTION:Cooled waste water from a cooling tower 2 is sent to a solid- liquid separation apparatus such as a thickner and a coagulant is added to said waste water to remove SS therein as a precipitate 11. The separated water of the cooled waste water is sent to an absorbing tower 3 to be added with an absorbent and the formed slurry is recirculated in the absorbing tower. SOx in a waste gas is contacted with the absorbing liquid to form CaSO3 and gypsum 6 is formed by oxidizing CaSO3 by air.