Removes hydrogen sulfide (H2S) from gas streams such as natural gas, refinery fuel gas, hydrogen recycle stream in refinery HDS, high-carbon dioxide (CO2) streams in EOR plants and geothermal vent gas. Also removes H2S, sulfur dioxide (SO2) and elemental sulfur vapor from Claus tail gas in natural gas processing plants and petroleum refineries. Can treat any high- or low-pressure gas stream. CrystaSulf is the most economical choice for H2S removal from gas streams containing between 0.2 and 25 long tons per day (ltpd) of sulfur (S).
Gas phase H2S is converted to elemental sulfur in a single process step using a proprietary nonaqueous sorbent. The sulfur formed remains dissolved in the solution; thus, no solids are present in the circulating scrubbing liquor. Sulfur is removed from the system by cooling in a crystallizer/filter system. No surfactants, wetting agents or antifoams are needed.
Scrubbing solution circulation rates are low (e.g., 20–50 gpm/ltpd) and product sulfur purity is high (98+% sulfur). It can be blended with Claus sulfur or used in agriculture. Chemical makeup costs are approximately $250/lt of sulfur. Capital and operating costs are less than other options, and the process requires no solution blowdown. For Claus tail gas treating, the tail gas is fed directly to the CrystaSulf absorber, thus eliminating the reducing gas generator, waste heat boiler, hydrogenation reactor and water quench. None of the gas needs to be recycled back to the Claus unit.
Operating conditions: Atmospheric to 2,000+ psi; 120°F to 180°F. CO2, COS and CS2 in the inlet gas do not react and do not affect the system. Inlet gas hydrocarbons do not cause foaming or sulfur settling problems for CrystaSulf.
Licensor: CrystaTech is the Gas Technology Institute’s (GTI) exclusive licensor of CrystaSulf. The Hanover Company and GTI are investors in CrystaTech and provide engineering and research support to CrystaTech. Hanover provides detailed design and fabrication of CrystaSulf units and can offer turnkey projects.