Abstract: An oxidation-reduction desulfurization system includes a reactor vessel with sour gas inlet at the bottom and a gas outlet at the top. A primary stage phase separator includes a vertically-oriented pipe with an inlet located inside the reactor vessel. The ratio of the reactor vessel diameter to the pipe inlet diameter is in a range of 2:1 to 5:1. Surface foam and non-gaseous multi-phase mixture including emulsion flow into a partially gas-filled upper section of the vertically-oriented pipe and freefall to a lower level, thereby facilitating mechanical breaking of the foam and the emulsion. A secondary stage phase separator connected to the gas outlet separates non-gaseous surge from sweet gas. Valves and a controller automatically maintain target levels of the non-gaseous multi-phase mixture and non-gaseous surge.

Abstract: An oxidation-reduction desulfurization system includes a reactor vessel with sour gas inlet at the bottom and a gas outlet at the top. A primary stage phase separator includes a vertically-oriented pipe with an inlet located inside the reactor vessel. The ratio of the reactor vessel diameter to the pipe inlet diameter is in a range of 2:1 to 5:1. Surface foam and non-gaseous multi-phase mixture including emulsion flow into a partially gas-filled upper section of the vertically-oriented pipe and freefall to a lower level, thereby facilitating mechanical breaking of the foam and the emulsion. A secondary stage phase separator connected to the gas outlet separates non-gaseous surge from sweet gas. Valves and a controller automatically maintain target levels of the non-gaseous multi-phase mixture and non-gaseous surge.

Abstract: A system for scrubbing and monitoring H2S includes: a sample inlet valve that controls an input stream of the hydrocarbon gas from the gas canister; a first scrubber that removes a first portion of H2S from the input stream and that outputs a first stream with less H2S than the input stream; a second scrubber that removes a second portion of H2S from the first stream and that outputs a second stream with less H2S than the first stream; a H2S converter that converts all remaining H2S in the second stream into a di-ketone and that outputs an output stream with a concentration of the di-ketone; an optical detector that measures the concentration of the di-ketone in the output stream; and a processor that determines a concentration of H2S in the second stream based on the concentration of the di-ketone in the output stream.

Abstract: An oxidation-reduction desulfurization system includes a reactor vessel with sour gas inlet at the bottom and a gas outlet at the top. A primary stage phase separator includes a vertically-oriented pipe with an inlet located inside the reactor vessel. The ratio of the reactor vessel diameter to the pipe inlet diameter is in a range of 2:1 to 5:1. Surface foam and non-gaseous multi-phase mixture including emulsion flow into a partially gas-filled upper section of the vertically-oriented pipe and freefall to a lower level, thereby facilitating mechanical breaking of the foam and the emulsion. A secondary stage phase separator connected to the gas outlet separates non-gaseous surge from sweet gas. Valves and a controller automatically maintain target levels of the non-gaseous multi-phase mixture and non-gaseous surge.

Abstract: Methods for removing reduced sulfur compounds, such as hydrogen sulfide, from fluids employing a ferric iron salt that exhibits unusually high solubility in aqueous, alkaline solutions and has strong affinity for capture and oxidation of reduced sulfur compounds. Alkaline aqueous ferric iron salt and solutions thereof useful for removing reduced sulfur compounds from fluids and various methods of production of such salts and solutions. In addition, methods of regenerating the alkaline aqueous ferric iron salt solutions after capture of hydrogen sulfide or other reduced sulfur compounds, generally by exposure to oxygen in air. The alkali metal carbonate salt preferably comprises potassium carbonate and/or potassium bicarbonate. The alkaline aqueous ferric iron salt solutions generally comprise ferric ions, potassium ions, carbonate ions, and bicarbonate ions, optionally with one or more organic additives.

Abstract: A catalytic composition and process for using same. The catalyst may be utilized for an oxidation reaction, for example, for the conversion of mercaptans to disulfides. The catalyst includes a metal component, for example, cobalt phthalocyanine structure. The organic component may comprise any number of different oxidation promoters that are capable of promoting the reduction of oxygen, preferably in a caustic, environment. The organic component may comprise an unsaturated six member ring having at least five carbon atoms, and wherein the sixth member of the six member ring is either C or N, and in which at least two substituent groups are present on the six membered ring.

Abstract: Methods and apparatuses are described for contacting an oxidizing solution such as an aqueous hydrogen peroxide composition of hydrogen peroxide, at least one additive that catalyzes the decomposition of the hydrogen peroxide into hydroxyl radicals, and a biocide with an atmospheric effluent containing odorous and/or noxious components. These components are absorbed by the aqueous hydrogen peroxide composition to produce an atmospheric effluent having reduced amounts of the odorous and/or noxious components. Various methods are described for adding the hydrogen peroxide, the decomposition additive, and the biocide.

Abstract: A process for recovering sulfur from a hydrogen sulfide-bearing gas utilizes an aqueous reaction medium, a temperature of about 110-150° C., and a high enough pressure to maintain the aqueous reaction medium in a liquid state. The process reduces material and equipment costs and addresses the environmental disadvantages associated with known processes that rely on high boiling point organic solvents.

Abstract: The present invention relates to a process for the catalytic oxidation of sulphide, mono- and/or dihydrogen sulphide, comprising the step of contacting the sulphide, mono- and/or dihydrogen sulphide in the presence of oxygen with a chelate complex comprising (i) a metal cation selected from the group consisting of Fez+, Mnz+, Niz+ and Coz+, where z=2 or 3, and (ii) a chelate ligand containing a porphyrin, a phthalocyanine or a porphyrazine ring coordinated to the metal cation, and at least one cationic substituent covalently attached to the ring in the chelate ligand.

Abstract: An improved process for reduction-oxidation desulphurization uses an oxidizer operating at a pressure greater than the absorber where a liquid reduction-oxidation catalyst solution contacts a sulfur-containing gas feed stream.

Abstract: An apparatus and method of contacting a liquid with different gases sequentially in separate mass transfer zones within a single vessel, the mass transfer zones operatively in fluid communication with each other, including intimately contacting the liquid with a process gas in co-current flow in a downstream mass transfer zone to effect mass transfer between the liquid and the process gas, and introducing the liquid into an upstream mass transfer zone with a second gas, different from the process gas, thereby effecting mass transfer between the liquid and the second gas. The rate of flow of the liquid from the upstream mass transfer zone to downstream mass transfer zone is controlled by the controlled addition of a third gas into one or more downcomers separating each mass transfer zone such that the specific density of the liquid in the downcomers provides a driving force that controls flow.

Abstract: A method for removing hydrogen sulfide from a sour gas stream comprising hydrogen sulfide by oxidizing hydrogen sulfide in a converter by contacting the sour gas stream with an aqueous catalytic solution, thereby producing a desulfurized gas stream and a liquid stream comprising reduced catalyst and elemental sulfur, introducing an oxidant and the liquid stream comprising reduced catalyst and elemental sulfur into a high shear device and producing a dispersion wherein the mean bubble diameter of the oxidant gas in the dispersion is less than about 5 ?m, introducing the dispersion into a vessel from which a sulfur-containing slurry is removed and a regenerated catalyst stream is removed, wherein the sulfur slurry comprises elemental sulfur and aqueous liquid, and recycling at least a portion of the regenerated catalyst stream to the converter. A system of apparatus for carrying out the method is also provided.

Abstract: The invention relates to a process for removing hydrogen sulfide and recovering sulfur from a gas stream, comprising the steps of: contacting said gas stream with an aqueous catalyst solution of a polyvalent metal redox catalyst in a contacting zone to absorb said hydrogen sulfide and form a reduced catalyst solution comprising reduced polyvalent metal redox catalyst and sulfur particles; oxidizing said reduced catalyst solution while removing sulfur particles to form said oxidized aqueous catalyst solution comprising polyvalent metal redox catalyst in an oxidized state with sulfur particles removed; and recovering sulfur by transferring at least one of said sulfur particles and foam to a separation zone; wherein a coagulating reagent is added to a feed of said separation zone prior to entering said separation zone to promote settlement of sulfur particles.

Abstract: The invention relates to a process for removing sulfur particles from an aqueous catalyst solution used to remove hydrogen sulfide from a gas stream (1, 5), comprising the steps of directing a flow of a suspension (12) comprising reduced catalyst solution and sulfur particles to an oxidizer zone (20), where the catalyst solution is regenerated by contacting said suspension with a gas (22) containing oxygen; and removing sulfur from said suspension at least by gravity sedimentation at a bottom (21) of said oxidizer zone (20). According to the invention a flow deflecting means (34) is disposed at least at an outlet (35) for the oxidized catalyst solution leaving said oxidizer zone (20) such as to prevent any turbulent state caused at least by a stream of oxidized catalyst solution leaving said oxidizer zone (20).

Abstract: An improved oxidizer for liquid reduction-oxidation desulphurization processes uses a hollow fiber membrane contactor. A pressurized, oxygen containing gas stream is introduced into the interior of the hollow fiber membrane while a liquid reduction-oxidation catalyst solution contacts the exterior of the membrane. Oxygen diffuses through the membrane into the liquid reduction-oxidation catalyst solution whereby the solution is oxidized and can be recycled for further use in a desulphurization process.

Abstract: An improved oxidizer for liquid reduction-oxidation desulphurization processes uses a hollow fiber membrane contactor. A pressurized, oxygen containing gas stream is introduced into the interior of the hollow fiber membrane while a liquid reduction-oxidation catalyst solution contacts the exterior of the membrane. Oxygen diffuses through the membrane into the liquid reduction-oxidation catalyst solution whereby the solution is oxidized and can be recycled for further us in a desulphurization process.

Abstract: The present invention relates to a process for regenerating an at least partly reduced catalytic redox solution. The solution includes at least one polyvalent metal chelated by a chelating agent and is circulated in at least one regeneration zone while an oxygen-containing gas is injected into the regeneration zone. The process includes measuring a concentration of oxygen dissolved in a regeneration zone effluent. The process also includes adjusting a flow rate of the at least partly reduce catalytic redox solution entering the at least one regeneration zone and/or an oxygen-containing gas entering the regeneration zone in response to a measured concentration of oxygen, until a concentration of oxygen in the regeneration zone effluent is less than 20% of an amount of oxygen dissolved in water saturated with oxygen. Thus, degradation of the chelating agent in the catalytic redox solution is minimized.

Abstract: In the desulfurization of a gaseous feed containing hydrogen sulfide, comprising contacting the gaseous feed with a catalytic solution containing a chelated polyvalent metal under suitable conditions for oxidation of the hydrogen sulfide to elementary sulfur and concomitant reduction of the chelated polyvalent metal from a higher oxidation level to a lower oxidation level, recovering a gaseous effluent substantially freed from hydrogen sulfide, and a catalytic solution at least partly reduced and containing elementary sulfur, separating the solid elementary sulfur from the reduced catalytic solution, and regenerating the reduced catalytic solution by contacting the catalytic solution with a gas containing oxygen by means of an ejector.

Abstract: A process intended for desulfurization of a gaseous feed containing hydrogen sulfide, includes at least the following stages: a) contacting the gaseous feed with a catalytic solution containing at least one polyvalent metal chelated by at least one chelating agent, under suitable conditions for oxidation of the hydrogen sulfide to elemental sulfur and concomitant reduction of the polyvalent metal from a higher oxidation level to a lower oxidation level, b) recovering on the one hand a gaseous effluent substantially freed from hydrogen sulfide and, on the other hand, the catalytic solution at least reduced and containing elemental sulfur, and c) recycling at least a fraction F1 of the catalytic solution at least reduced and containing solid elemental sulfur to absorption stage a) so as to reduce the number of sulfur grains of very small size.

Abstract: A method is provided for increasing the lifetime of Stretford solution by reducing or eliminating the generation of undesirable thiosulfate salts. The method has three major aspects. First, thiocyanate is added to the Stretford solution. Second, the concentration of sodium sulfate in the solution is maintained at a level below about 100 g/l. Third, the solution should contain little or no thiosulfate at the start of operations. It has been found that little or no thiosulfate is generated when the Stretford unit is operated under these conditions. The concentration of sodium sulfate in the solution is maintained at a level below about 100 g/l by removing sodium sulfate from the solution by cooling a slipstream of the solution to precipitate the sodium sulfate as Glauber's salt.

Abstract: A process is described for regenerating an at least partly reduced catalytic redox solution, whereby said process includes at least one complexing agent of a polyvalent metal that is associated with the solution in which the solution is circulated in a regeneration zone in the presence of an oxygen-containing gas under appropriate regeneration conditions, and a regeneration effluent is recovered that is at least partly oxidized. The concentration of the oxygen that is dissolved in the regeneration effluent is measured, and the operating parameters are adjusted so as to minimize the degradation of the complexing agent and to regenerate the catalytic solution, at least in part.

Abstract: A process for the removal of thiosulphate from spent Stretford solution, The process comprises adjusting the spent Stretford solution to an acidic pH, preferably in the range of 1 to 3, and adding a peroxygen compound. The process allows the user to recycle spent Stretford solution in a cost effective manner by taking advantage of previously unknown buffering properties in the solution.