Chementator: A Process for Desulfurizing Natural Gas  

A process in which sulfur is extracted from natural gas in the field and converted to sulfur dioxide, which is then injected into the gas reservoir and reacts with hydrogen sulfide in situ to produce elemental sulfur, has been developed by Black & Veatch (Overland Park, Kan.; edlinks.chemengonline.com/7372-535) and Alberta Sulphur Research Ltd. (Calgary, Alta.; edlinks.chemengonline.com/7372-536). The partners have formed a consortium of oil companies to demonstrate the process in a large-scale field test. The Sulfur To Energy Process (STEP) was conceived by Peter Clark, director of research for Alberta Sulphur Research, and has been tested in the laboratory. H2S is extracted from natural gas by an amine and converted to elemental sulfur by the Claus process. The sulfur is then burned with air or oxygen-enriched air to produce SO2, which is cooled and liquefied at about 100°F and 200 psi. Heat recovered from this step can be used for process heat or electricity production. The liquid SO2 is compressed to about 500 psi and injected into the ground. Clark says STEP is economically attractive for remote locations such as northern Alberta and Central Asia, where sulfur has to be stockpiled because of the high cost of transporting…