Manufacture of hydrogen sulfide

Abstract

Methods and apparatus adaptable to continuous production of hydrogen sulfide by chemical reaction of sulfur with a gaseous sulfur-reducing reactant selected from methane or other hydrocarbons, hydrogen, carbon-containing compounds such as carbon disulfide, gases with high CO contents, e.g. from gasification of coal, or mixtures of such gases are provided utilizing a separately-fired sulfur heater to vaporize liquid sulfur feedstock. Adding steam with the sulfur reduces the temperature level requirements of the sulfur vapors and provides H.sub.2 and O.sub.2 for the hydrolysis reactions. Control of the temperature of the sulfur vapors and steam delivered into the system through the sulfur vaporizer is used to modulate sulfiding reaction temperatures. A major portion of the steam is introduced with the sulfur vapors; a minor portion of the steam can be added with the feedstock reductant gas to assist in heat recovery from the reaction product gases and to facilitate standby conditions. During production, the system is operated at pressures above atmospheric as determined by a back pressure established in removing product gases containing hydrogen sulfide. Controlled movement of reactants and reaction product gases through the system is achieved without requiring mechanical flow control equipment in any of the relatively high temperature zones approaching sulfiding reaction temperatures or sulfur vaporizing temperature. Requirements for on-site storage of toxic and explosive hydrogen sulfide are eliminated. The separately-fired sulfur vaporizer provides for circulation of sulfur and/or steam, without feedstock reductant gas in various production standby modes, which make production on demand readily available.