Application: Removal of H2S and the production of high-purity sulfur from both anaerobic and aerobic gas streams including wellhead gas, fuel gas, acid gas, natural gas, carbon dioxide, Claus tail gas, synthesis gas and ventilating-air streams. Infinite turndown with respect to H2S concentration, sulfur loading and gas rate with sulfur capacities ranging from a few pounds per day to greater than 25 ltpd. Recovery of the sulfur product as a slurry, a filter cake or as high-purity, molten sulfur. In most cases, sulfur cake can be deposited in a non-hazardous landfill. Autocirculation configuration when treating amine acid gas allows for remote or unattended operation typical for gas field operation.
Three processing configurations are available depending on the type of gas and final use of the sweet gas. The conventional scheme, shown above, is used to process both combustible gas streams and product gas streams. The sour gas contacts a dilute, proprietary, iron chelate catalyst solution in an absorber (1), where the H2S is absorbed and oxidized to solid sulfur. The sweet gas leaves the absorber for use by the client. The reduced catalyst solution returns to the oxidizer (2), where sparged air reoxidizes the catalyst solution. The catalyst solution is then returned to the absorber. The continuous regeneration of the catalyst solution allows for very low chemical operating costs.
In the patented autocirculation scheme, the absorber (1) and the oxidizer (2) are combined in one vessel, but separated internally by baffles. Sparging of the sour gas and regeneration air into the specially designed baffle system creates a series of “gas lift” pumps eliminating the external circulation pumps. This configuration is ideally suited for treating amine acid gas streams.
The third processing scheme sweetens air streams contaminated with H2S. The absorption and oxidation of H2S to sulfur, as well as the regeneration of the catalyst solution, occur in one vessel. The air in the gas stream is used to regenerate the catalyst, eliminating the oxidizer air blowers.
Operating conditions: Operating pressures from vacuum conditions to several hundred psi. Operating temperatures range from 40°F to 140°F. Hydrogen sulfide concentrations from a few ppm to 100%. Sulfur loadings from a few lb/d to 25+ ltpd. No restrictions on type of gas to be treated; however, some contaminants such as SO2 may increase operating costs.
Licensor: Gas Technology Products LLC, a Merichem Co.