The Direct Chlorination Process for Hydrogen Sulfide Abatement

Abstract

The Direct Chlorination Process removes hydrogen sulfide from geothermal off gases by reacting hydrogen chloride with elemental sulfur are formed by this reaction. The Direct Chlorination Process has been successfully demonstrated by an on tie operation of a pilot plant at the 3 MWe HPG-A geothermal power plant in Hawaii. Over 99.5 percent hydrogen sulfide removal was achieved in a single concurrent reaction stage. Chlorine gas did not escape the pilot plant, even when 90 percent excess chlorine gas was used. A preliminary economic evaluation indicates that, when compared with eth Stretford Process, the Direct Chlorination Process required about one third the initial capital investment and about one fourth the net daily expenditure. Because of the higher cost of chemicals and the restricted markets in Hawaii, the economic viability of this process in Hawaii is questionable.