TREATMENT OF WASTE GAS CONTAINING GASEOUS CHLORINE AND DEVICE THEREFOR

摘要

PURPOSE:To neutralize a hypochlorite at high pH and to eliminate the need for measuring pH and oxidation-reduction potential by allowing a part of a liq. absorbent contg. a salt formed by the reaction with a waste gas to react with sodium thiosulfate in an alkali side. CONSTITUTION:A waste gas is introduced into an absorption tower 1, and a liq. absorbent is supplied to the tower 1 by an absorbent circulating pump 2 and a contaminated absorbent transport pump 3. An aq. sodium hydroxide soln. kept at about pH10-12 is used as the absorbent, and the waste gas is sufficiently mixed with the absorbent in the tower 1. Sodium chloride formed by the absorption reaction and the absorbent contaminated with sodium hypochlorite are drawn off at all times in a fixed amt. from the bottom of the tower 1 by the pump 3 and sent to a reducing and detoxicating tank 6 together with the sodium thiosulfite which is mixed in a fixed amt. at all times by a reducing agent delivery pump 5. The contaminated absorbent and sodium thiosulfite are sufficiently mixed in the tank still at high pH and detoxicated.