Abstract: A method for producing sulfur and energy from an acid gas stream containing hydrogen sulfide by partially combusting the acid gas stream to produce a combustion product gas, mixing a sulfur dioxide stream with the combustion product gas, separating sulfur from the mixture, combusting sulfur to produce sulfur dioxide and heat energy and passing at least a portion of the sulfur dioxide to the combustion product gas.

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: The present invention comprises a method of treating an off-gas stream from a refining process to remove sulfur compounds. A portion of the off-gas stream containing hydrogen sulfide is injected at the front end of the thermal reactor and in at least one other location downstream of the thermal reactor. A ratio of hydrogen sulfide to sulfur dioxide at the outlet of the thermal reactor is less than the stoichiometric requirement. The ratio is adjusted downstream of the thermal reactor so that a ratio of hydrogen sulfide to sulfur dioxide is maintained substantially in excess of the stoichiometric requirement for a Claus reaction. The tail gas, containing hydrogen sulfide but virtually no sulfur dioxide, is treated by a process including removal of water and introducing sulfur dioxide into the tail gas in a stoichiometricly balanced quantity and processing the tail gas in a Claus reactor.

Abstract: A compact sulfur recovery system is disclosed which comprises a primary structure including a catalytic partial oxidation reaction zone, a first temperature-control zone, a first Claus catalytic reaction zone, a second temperature-control zone, a first liquid sulfur outlet, and a first effluent gas outlet. In some embodiments, a secondary structure follows the primary structure and comprises a second Claus catalytic reaction zone, a third temperature-control zone, a second liquid sulfur outlet, and a second effluent gas outlet. One or more components of the system employ heat transfer enhancement material in the temperature-control zones, and one or more components deter accumulation of liquid sulfur in the Claus catalytic reaction zones.

Abstract: Apparatus and process for recovering elemental sulfur from a H2S-containing waste gas stream are disclosed. The apparatus preferably comprises a first reaction zone for carrying out the catalytic partial oxidation of H2S, a second reaction zone for the catalytic partial reduction of any incidental SO2 produced in the first reaction zone, and a cooling zone including a sulfur condenser. According to a preferred embodiment of the process, a mixture of H2S and O2 contacts a catalyst in the first reaction zone very briefly (i.e, less than about 200 milliseconds) producing primarily S0 and H2O. Some SO2 is also present in the first stage product gas mixture. A reductant gas (e.g. CO, or CH4 or natural gas) is fed together with the first stage product gas mixture to a second catalytic reaction zone where the partial reduction of the SO2 component to elemental sulfur and CO2 is carried out.

Abstract: A process for removing hydrogen sulfide, other sulfur-containing compounds and/or sulfur and mercury from a gas stream contaminated with mercury, hydrogen sulfide or both. The method comprises the step of selective oxidation of hydrogen sulfide (H2S) in a gas stream containing one or more oxidizable components other than H2S to generate elemental sulfur (S) or a mixture of sulfur and sulfur dioxide (SO2). The sulfur generated in the gas stream reacts with mercury in the gas stream to generate mercuric sulfide and sulfur and mercuric sulfide are removed from the gas stream by co-condensation.

Abstract: A process for removing sulfur from a H2S-containing gas stream is disclosed. A preferred embodiment of the process comprises incorporating a short contact time catalytic partial oxidation reactor, a cooling zone, and a condenser into a conventional refinery or gas plant process, such as a natural gas desulfurizer, a hydrotreater, coker or fluid catalytic cracker, in which sulfur removal is needed in order to produce a more desirable product. An H2S-containing gas stream is fed into a short contact time reactor where the H2S is partially oxidized over a suitable catalyst in the presence of O2 to elemental sulfur and water.

Abstract: An apparatus and process for recovering elemental sulfur from a H2S-containing waste gas stream are disclosed, along with a method of making a preferred catalyst for catalyzing the process. The apparatus preferably comprises a short contact time catalytic partial oxidation reactor, a cooling zone, and a sulfur condenser. According to a preferred embodiment of the process, a mixture of H2S and O2 contacts the catalyst very briefly (i.e, less than about 200 milliseconds). Some preferred catalyst devices comprise a reduced metal such as Pt, Rh, or Pt—Rh, and a lanthanide metal oxide, or a pre-carbided form of the metal. The preferred apparatus and process are capable of operating at superatmospheric pressure and improve the efficiency of converting H2S to sulfur, which will reduce the cost and complexity of construction and operation of a sulfur recovery plant used for waste gas cleanup.

Abstract: A process is described for the elimination of hydrogen sulfide from gas mixtures by catalytic oxidation over activated carbon catalyst which converts the hydrogen sulfide to elemental sulfur and water, the former being sorbed by the activated carbon while the latter is transported with the gas mixture and may be removed by known dehydration processes. The above oxidative process is conducted at elevated temperatures and pressures and with sufficient residence time to assure virtually complete conversion of the hydrogen sulfide with minimal production of by-product sulfur dioxide. Traces of heavy hydrocarbons in the feed gas mixture which may reduce the life of the catalyst and the quality of the sulfur product may be removed by cryogenic means or by sorption on an activated carbon guard bed.

Abstract: Sour gas containing hydrogen sulphide has hydrogen sulphide absorbed therefrom in an absorbent in a vessel 4. A hydrogen sulphide rich gas stream is formed by desorbing hydrogen sulphide from the absorbent in a vessel 12. The resulting hydrogen sulphide rich gas stream is partially burned in a furnace 32. Resulting sulphur dioxide reacts therein with residual hydrogen sulphide to form sulphur vapor which is extracted in a condenser 44. Residual sulphur dioxide and sulphur vapor are reduced to hydrogen sulphide in catalyst stage 54 of a reactor 50. Water vapor is removed from the resulting reduced gas stream by direct contact with water in a quench tower 60. At least part of the resulting water vapor depleted gas stream is sent to the vessel 4 with the incoming sour gas stream.

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, system and catalysts for improving the yield of syngas from the catalytic partial oxidation of methane or other light hydrocarbons is disclosed. The increase in yield and selectivity for CO and H2 products results at least in part from the substitution of H2S partial oxidation to elemental sulfur and water for the combustion of light hydrocarbon to CO2 and water.

Abstract: Disclosed is a method in which hydrogen sulfide-containing liquid sulfur is introduced into a containment vessel to partially fill the containment vessel and create a hydrogen sulfide-containing liquid sulfur phase and a hydrogen sulfide-containing vapor phase. A portion of the hydrogen sulfide-containing liquid sulfur phase is then treated to produce a liquid sulfur-containing phase and a gaseous hydrogen sulfide-containing phase, such that the gaseous hydrogen sulfide-containing phase has a pressure of at least about 60 psig. A portion of the hydrogen sulfide-containing vapor phase is then withdrawn from the containment vessel using at least one eductor driven by a motive fluid, where the motive fluid is the gaseous hydrogen sulfide-containing phase from the container vessel. The hydrogen sulfide-containing waste gas stream exiting the eductor is then treated to reduce the hydrogen-sulfide content of the waste gas.

Abstract: Hydrogen sulfide is removed from gas streams by reaction with sulfur dioxide to produce sulfur. The reaction is effected in a reaction medium comprising a non-aqueous Lewis base with a pKb value of about 6 to about 11. The reaction medium possesses a specific combination of properties: a) absorbs sulfur dioxide and reacts chemically therewith to form a reaction product; b) absorbs hydrogen sulfide; c) removes the hydrogen sulfide from the gas stream through contact of the gas stream with the reaction medium in the presence of free sulfur dioxide, and/or the reaction product; d) acts as a catalyst for the overall reaction of the hydrogen sulfide with sulfur dioxide to produce sulfur; and (e) has the capacity to absorb sulfur dioxide in sufficient quantity to remove substantially all the hydrogen sulfide from the gas stream, notwithstanding short term variations in the stoichiometric balance between the hydrogen sulfide and the sulfur dioxide in the reaction medium.

Abstract: A process is provided for the removal of hydrogen sulfide out of a gaseous stream (22), such as a natural gas, by contacting the hydrogen sulfide containing gas with a sorbing liquid (26) containing a tertiary amine so that the hydrogen sulfide is sorbed into the liquid in absorber (11) and transferring the sorbing liquid/hydrogen sulfide mixture to a reactor (15) where the tertiary amine promotes the conversion of the hydrogen sulfide into polysulfide via reaction with sulfur; transferring the polysulfide solution from the reactor (15) to a regenerator (10) where polysulfide is converted into elemental sulfur via reaction with air (9); transferring at least a portion of the solution (25) containing elemental sulfur, as well as sulfate and thiosulfate species, into a mixture (36) where it is contacted with gaseous ammonia which reacts with the sulfate and thiosulfate species to produce ammonium sulfate and ammonium thiosulfate which are removed from the solution while the remaining portion of solution (25) is

Abstract: High quality hydrophilic sulfur is recovered from a biologial conversion zone in which a sulfur containing compound such as a sulfide is converted to elemental sulfur. The sulfur is rendered hydrophilic due to the fine particle size and attachment of biomass to the particles. The sulfur is recovered as an undamaged agglomerate powder after being processed in at least two stages of purification.

Abstract: A feed gas stream containing hydrogen sulphide is subjected in a furnace 6 to reactions in which part of the hydrogen sulphide is burned to form sulphur dioxide, and is which the sulphur dioxide reacts with residual hydrogen sulphide to form sulphur vapor. The sulphur vapor is condensed from the gas stream exiting the furnace 6 in a sulphur condenser 16. Residual sulphur dioxide is reduced back to hydrogen sulphide by hydrogen in a reactor 22. Water vapor is removed from the reduced gas in a quench tower 28 to form a water vapor-depleted gas stream. One part of the water vapor-depleted gas stream is sent to an adsorber vessel 30 in which hydrogen sulphide is absorbed in an absorbent. The resulting hydrogen sulphide-depleted gas stream is vented from the vessel 30 as a purge stream. Another part of the water vapor-depleted gas stream and a hydrogen sulphide-rich gas formed by desorbing hydrogen sulphide from the absorbent in a vessel 38 are returned as recycle streams to the furnace 6.

Abstract: In a known process and system wherein hydrogen sulfide is removed from a gaseous stream, using a non-aqueous scrubbing liquor which can be an organic solvent for elemental sulfur such as a phenylxylyl ethane in which are dissolved sulfur and a reaction-promoting amine base such as a tertiary amine, sulfur dioxide is added to the sulfur-amine nonaqueous sorbent (or advantage is taken of SO2 which may already be present in the gas stream) to obtain better H2S removal, lower chemical degradation rates, and lower rates of formation of byproduct sulfur salts such as sulfates.

Abstract: A process and an apparatus are described for treatment of a gas containing hydrogen sulphide and sulphur dioxide, for example a Claus plant tail gas, in which the gas is brought into contact with an organic solvent (1) e.g. polyethylene glycol 400, containing a catalyst e.g. sodium salicylate, in at least one gas-liquid reactor-contactor (2) and a gas (20) substantially no longer containing hydrogen sulphide and sulphur dioxide is recovered. A single-phase solution (4) of solvent and sulphur is extracted from the reactor-contactor and a portion is cooled in at least one cooling zone (8) to obtain a suspension of sulphur crystals in the solvent, the crystallised sulphur is separated from the solvent in a separation zone (10), the sulphur-depleted solvent (14, 15) is recovered and recycled at least in part to the reactor-contactor (2), and the sulphur (13) is recovered.

Abstract: A method, apparatus and system for treating a stream containing H2S are disclosed. A preferred method comprises mixing the stream containing H2S with a light hydrocarbon stream and an oxygen containing stream to form a feed stream; contacting the feed stream with a catalyst while simultaneously raising the temperature of the stream sufficiently to allow partial oxidation of the H2S and partial oxidation of the light hydrocarbon to produce a product stream containing elemental sulfur, H2O, CO and hydrogen, and cooling the product stream sufficiently to condense at least a portion of the elemental sulfur and produce a tail gas containing CO, H2, H2O and any residual elemental sulfur, and any incidental SO2, COS, and CS2 from the hydrocarbon stream or produced in the process. The tail gate is contacted with a hydrogenation catalyst so that CO is then reacted with water to produce CO2 and hydrogen and any elemental sulfur, SO2, COS, and CS2 in the tail gas is preferably converted into H2S.

Abstract: A method for processing a gas, such as a Claus tail gas, containing at least hydrogen sulfide (H2S) and at least sulfur dioxide (SO2), includes the steps of contacting the gas with a liquid solvent, such as polyethylene glycol, containing at least one catalyst, such as sodium salicylate, in a contacting stage, recovering gaseous effluent substantially containing no hydrogen sulfide and no sulfur dioxide from the contacting stage, and separating liquid sulfur from liquid solvent in a decantation zone beneath the contacting stage.

Abstract: A method for processing a gas containing at least hydrogen sulfide (H2S) and at least sulfur dioxide (SO2), includes the following stages: contacting the gas with a liquid solvent, such as polyethylene glycol, containing at least one catalyst, such as sodium salicylate, in a contacting stage, recovering a gaseous effluent substantially containing no hydrogen sulfide and no sulfur dioxide, and a mixture containing liquid sulfur, liquid solvent and solid by-products such as alkali metal or alkaline earth metal sulfates or thiosulfates, resulting from the degradation of the catalyst, separating the liquid sulfur from the liquid solvent in a decantation zone, extracting a liquid fraction F containing at least the solid by-products from a layer between the liquid solvent and the liquid sulfur in the decantation zone, sending the liquid fraction F to a processing stage distinct from the contacting stage, and recovering at least a stream F, comprising most of the solid by-products and a stream F2 mostly comprising s

Abstract: A regenerative process for oxidizing H2S contained in low concentration in a gas directly to sulphur including combining the H2S-containing gas with a gas containing free oxygen in an amount to form an O2/H2S-containing gas with an O2/H2S molar ratio ranging from 0.05 to 15; contacting the O2/H2S-containing gas with a catalyst for the selective oxidation of H2S to sulphur, wherein the catalyst includes a catalytically active phase containing at least one oxysulphide of at least one metal selected from the group consisting of nickel, iron, cobalt, copper, chromium, molybdenum and tungsten combined with a silicon carbide support and including a compound of at least one transition metal, at temperatures below the dew point of the sulphur formed by oxidation of H2S and depositing the sulphur on the catalyst; periodically regenerating by flushing the sulphur-laden catalyst using a non-oxidizing gas at temperatures of between 200° C. and 500° C.

Abstract: The present invention is a process wherein a process gas comprising at least SO2 and H2S is reacted across a stage of SO2 reducing catalyst, thereby obtaining high conversion of at least the SO2 to elemental sulfur.

Abstract: In wet oxidizing process of an aqueous alkali waste which contains absorbed hydrogen sulfide and carbon dioxide, a convenient method for improving the safety in oxidizing operation and the efficiency in oxidation reaction.