COMPOSITE TREATING AGENT FOR SOUR GAS AND HEAVY METAL, AND METHOD FOR TREATING SOUR GAS AND HEAVY METAL

摘要

PROBLEM TO BE SOLVED: To make it possible to sufficiently reduce the alkalinity of a fly ash in a wide addition amount range in order to solve the problem of a subsequent fly ash treatment process resulting from excess or deficiency of a sour gas treating agent generating accompanying the quality change of a waste.SOLUTION: A composite treating agent for sour gas and heavy metals includes a double salt composed by containing calcium hydroxide and magnesium hydroxide, and at least one compound (alkalinity reducing agent) selected from chlorides, sulfates and hydroxides. Preferably, the specific surface area and median size (d50) of the double salt are 20 m/g or more and less than 30 μm, respectively. Besides, the alkalinity reducing agent includes preferably at least one selected from magnesium sulfate, sulfate-containing aluminum hydroxide, zinc sulfate, copper sulfate, magnesium hydroxide, aluminum hydroxide, iron hydroxide, zinc hydroxide and copper hydroxide.SELECTED DRAWING: Figure 3