DEVICE FOR PRODUCING AMMONIUM SULFATE SOLUTION CAPABLE OF REMOVING SO2 FROM FLUE GAS AND TURNING INTO VALUABLE MATERIAL

摘要

PROBLEM TO BE SOLVED: To obtain 2 kinds of solutions respectively having a different quality by providing an absorbing liquid distribution device at the upper side of a cleaning zone, through which a flue gas is passed from the lower side to the upper side, a gas permeable liquid collecting bottom part at the lower side of the cleaning zone, an ammonium sulfite oxidation device and a drawing conduit, a circulating system of an absorbing liquid, a gas quenching liquid spray, a circulation device and the like. SOLUTION: The flue gas, in which hydrogen halide is separated in a gas passage 6 by the spray of NaOH or KOH solution through a conduit 16, is cooled by the ammonium sulfate solution of a spray device 7 and saturated with steam. In the cleaning zone 2, the SO2 loaded flue gas is brought into contact with a mixed absorbing liquid of an aq. ammonia, an ammonium sulfate aq. solution and the newly produced ammonium, sulfite solution. A branched flow of the absorbing liquid from the gas permeable collecting bottom part 8 is supplied to the oxidation device 5 by an absorbing liquid circulation system 9 and another part is circulated and supplied through a conduit 10. Ammonium sulfite and ammonium hydrogen sulfite is oxidized into ammonium sulfate by an oxygen-containing gas in the oxidation device 5 and two solutions respectively having a different concentration are obtained respectively from a liquid storage part of the device 5 and a liquid for quenching.