Gas purification method and apparatus for black liquor gasification power generation system

摘要

PROBLEM TO BE SOLVED: To provide the subject method comprising using part of quicklime produced from a kiln as an adsorbent for removing the Na- and S-based impurities in a gas produced by gasification of pulp cooking waste liquor so as to seek cost reduction for related power and equipment. SOLUTION: The subject power generation system works as follows: pulp cooking waste liquor is gasified with a black liquor gasification furnace 12, the resulting gas is introduced into a moving bed-type gas purifier 16 where the Na- and S-based impurities in the gas are adsorbed to an adsorbent and removed, and the resulting purified gas is combusted to drive a gas turbine 20 to conduct a power generation; wherein the waste liquor in the black liquor gasification furnace 12 is fed, together with quicklime, to causticizer 38 where it is causticized, the causticized liquor is then incorporated with hydrogen sulfide and sodium hydroxide to use as pulp cooking liquor; concurrently, part of the above-mentioned quicklime is used as the adsorbent mentioned above, and the adsorbent thus used is either recycled as quicklime with a limestone pyrolyzing kiln 40 or recovered as gypsum.