Abstract: Sulfur sought to be removed from deposits formed at a subterranean gas producing well is dissolved in a high boiling point relatively pure and low cost non-aqueous solvent. The dissolved sulfur is then removed from the solvent by lowering the temperature of the solution to precipitate the sulfur which is then separated and recovered as a relatively pure product. After additional processing the regenerated solvent is injected back down the well hole to dissolve additional sulfur and reutilized in successive cycles of the process. An amine or solubilizing agent may be added to the non-aqueous solvent, and an oxidizing agent may be provided during the process to oxidize polysulfides to sulfur.

Abstract: The invention provides a method of testing sour natural gas by a) removing H2S from the gas stream, b) converting H2S to elemental sulfur, and c) recovering elemental sulfur. The invention also provides a substantially mobile system for testing sour natural gas including vehicles allowing the equipment to be operated on surfaces such as the flat beds of trailers. The system features equipment that may be mounted within one or more support structures situated on a mobile vehicle, such as, for instance the flat bed of a trailer. The one or more support structures hold each piece of equipment substantially fixed in place on the vehicles. Each surface such as the flat bed of a trailer may carry one, two or more pieces of equipment. The equipment may include, for instance, an air or oxygen compressor, a knockout vessel, a gas heater, an air heater, a cooler, a molten sulfur separator and a thermal oxidizer.

Abstract: Sulfur sought to be removed from deposits formed at a subterranean gas producing well is dissolved in a high boiling point relatively pure and low cost non-aqueous solvent. The dissolved sulfur is then removed from the solvent by lowering the temperature of the solution to precipitate the sulfur which is then separated and recovered as a relatively pure product. After additional processing the regenerated solvent is injected back down the well hole to dissolve additional sulfur and reutilized in successive cycles of the process. An amine or solubilizing agent may be added to the non-aqueous solvent, and an oxidizing agent may be provided during the process to oxidize polysulfides to sulfur.

Abstract: A process is provided for removing vapor phase selenium species produced by the combustion of selenium and sulfur-containing fuel of the kind used to generate electric power in conjunction with a flue gas desulfurization process. In one process embodiment the flue gas leaving the combustion system is humidified by the injection of atomized water or a dilute alkaline slurry at a selected location upstream of the flue gas desulfurization system to cool the flue gas from a temperature of about 300.degree. F. to a temperature of about 280.degree. F. so as to enhance the selenium removal efficiency. In another process embodiment the flue gas leaving the combustion system is first humidified to cool the flue gas from a temperature of about 300.degree. F. to a temperature of about 200.degree. F. so as to enhance the selenium removal efficiency, and then an alkaline sorbent material is injected into the humidified flue gas.