METHOD OF TREATING WASTE WATERS FROM A FLUE GAS DESULPHURISER

摘要

The present invention provides a desulfurization waste water treatment method for treating waste water discharged from a wet type flue gas desulfurizer for absorbing and separating sulfur oxide in combustion flue gas by using a wet lime-gypsum process, wherein after hypochlorite is added to the waste water, the pH value is adjusted to 7 to 9.5, and the waste water is subjected to solid-liquid separation; and a flue gas desulfurization method using a wet lime process for treating flue gas containing sulfur oxide and nitrogen oxide, comprising an oxidation process in which the pH value of all or some of filtrate is adjusted to 3 to 4 and an oxidizing agent is added after some of absorbent slurry in a desulfurization process is extracted and gypsum is separated, a neutralization process in which an alkaline agent is mixed with the mixed liquid to adjust the pH value to 7 to 9.5, and a solid-liquid separation process in which the neutralized adjusted liquid is subjected to solid-liquid separation. According to the present invention, NS compounds having an adverse influence on the desulfurization performance can be removed effectively, and at the same time, heavy metals, especially manganese, in desulfurization waste water can be removed favorably in terms of economy as well. <IMAGE>