PURPOSE: To attain to reduce utility, by a method wherein the part of an exhaust gas containing sulfur dioxide gas and oxygen is subjected to gas-liquid contact with an absorbing liquid to recover sulfate through reaction and oxidation.
CONSTITUTION: Exhaust gas 101 of a boiler or the like is guided to a dust removing tower 1 from the inlet duct 31 thereof to remove dust therein and, after cooling, scattered mist is removed by a mist eliminator 2 while the treated gas is introduced into an adsorbing tower 3. In this adsorbing tower 3, sulfur oxide in the exhaust gas 101 is absorbed and removed by a calcium type absorbent slurry 22 and the purified gas 102 is exhausted from the duct 32 of the tower top. The calcium type absorbent slurry 22 having sulfur oxide absorbed therewith converted to sulfite and the part thereof is converted to gypsum. In addition, a reaction slurry containing the unreacted absorbent corresponding to the absorbing amount of sulfur oxide is withdrawn from the recirculation line 4 of the absorbing tower to be supplied to reactor 8. In this case, the part 103 of the gas after dust is removed is guided to the reactor 8 to form sulfite.
ASANO HIROMITSU
NOZAWA SHIGERU
| JPS5575727A | 1980-06-07 |