A process and apparatus for managing hydrogen sulfide in a refinery is provided. In the process, a hydrogen sulfide stream from said refinery is fed to a sulfur recovery unit to produce sulfur and a sulfur compound stream or to a thermal oxidizer. The sulfur compound stream and the hydrogen sulfide stream are then thermally oxidized to produce a sulfur oxide stream. The sulfur oxide stream is then reacted with an ammonia stream. In aspect, the product of the reaction can be a fertilizer. The ammonia stream can be obtained from stripping the hydrogen sulfide stream.

A method for recovering sulfur within a gas processing system is described herein. The method includes contacting a natural gas stream including an acid gas with a solvent stream within a co-current contacting system to produce a sweetened natural gas stream and a rich solvent stream including an absorbed acid gas. The method also includes removing the absorbed acid gas from the rich solvent stream within a regenerator to produce a concentrated acid gas stream and a lean solvent stream. The method further includes recovering elemental sulfur from hydrogen sulfide (H.sub.2S) within the concentrated acid gas stream via a sulfur recovery unit.

Provided here are methods and systems to recover greater than 99.9% of sulfur from natural gas and from other processed gases containing hydrogen sulfide derived from refining crude oil and other industrial processes. The method and system involves a sub-dew point reactor unit with separation units for water removal.

The invention relates to a gas scrubbing process for purifying crude synthesis gas with methanol as a physical absorption medium, wherein an acid gas comprising at least hydrogen sulfide (H.sub.2S) is produced. The acid gas is produced in a hot regenerator arranged downstream of an absorption apparatus and subsequently separated from gaseous methanol in an acid gas separator by cooling and condensation. The acid gas separator has a condensation region and an absorption region, wherein both regions are separated from one another by a gas-permeable tray. This has the result that impurities such as hydrogen cyanide and/or ammonia outgassing from a first acid gas substream are not reabsorbed in the condensation region of the acid gas separator, thus avoiding an accumulation of impurities in the hot regenerator or other parts of the gas scrubbing plant. The invention further relates to an acid gas separator and to the use of the acid gas separator according to the invention in a process according to the invention.

Systems and methods use bimetallic alloy particles for converting hydrogen sulfide (H.sub.2S) to hydrogen (H.sub.2) and sulfur (S), typically during multiple operations. In a first operation, metal alloy composite particles can be converted to a composite metal sulfide. In a second operation, composite metal sulfide from the first operation can be regenerated back to the metal alloy composite particle using an inert gas stream. Pure, or substantially pure, sulfur can also be generated during the second operation.

A method for sulfur recovery includes, in a hydrogenation reactor, converting sulfur-containing compounds in a Claus tail gas stream to hydrogen sulfide to produce a hydrogenated gas stream; feeding the hydrogenated gas stream to a quench tower to produce a quenched gas stream by condensing liquid water; feeding the quenched gas stream to a first stage adsorption vessel of a first stage adsorption unit to produce a first outlet gas stream by adsorbing water from the quenched gas stream; feeding the first outlet gas stream to a second stage adsorption vessel of a second stage adsorption unit to produce a second byproduct gas stream by adsorbing hydrogen sulfide from the first outlet gas stream; separating the second byproduct gas stream into a carbon dioxide stream and an enriched nitrogen stream; and regenerating the second stage adsorption vessel using the enriched nitrogen stream.

The invention concerns a method for treating a hydrocarbon feed gas stream containing at least CO.sub.2 and H.sub.2S to recover a high quality purified CO.sub.2 gas stream, comprising a. Separating said hydrocarbon feed gas stream into a sweetened hydrocarbon gas stream, and an acid gas stream; b. Introducing said gas stream into a Claus unit, c. Introducing the tail gas into a hydrogenation reactor and then into a quench contactor of the Tail Gas Treatment Unit (TGTU); d. Contacting said tail gas stream with a non-selective amine-based solvent into a non-selective acid gas absorption unit of the TGTU; e. Sending the off gas to an incinerator; f. Contacting said enriched gas stream (vii) with a selective H.sub.2S-absorption solvent into a selective H.sub.2S-absorption unit thereby recovering a highly purified CO.sub.2 gas stream and a H.sub.2S-enriched gas stream, as well as the device for carrying said method.

A process and apparatus for managing hydrogen sulfide in a refinery is provided. In the process, a hydrogen sulfide stream from said refinery is fed to a sulfur recovery unit to produce sulfur and a sulfur compound stream or to a thermal oxidizer. The sulfur compound stream and the hydrogen sulfide stream are then thermally oxidized to produce a sulfur oxide stream. The sulfur oxide stream is then reacted with an ammonia stream. In aspect, the product of the reaction can be a fertilizer. The ammonia stream can be obtained from stripping the hydrogen sulfide stream.

A process for recovering sulfur and carbon dioxide from a sour gas stream, the process comprising the steps of: providing a sour gas stream to a membrane separation unit, the sour gas stream comprising hydrogen sulfide and carbon dioxide; separating the hydrogen sulfide from the carbon dioxide in the membrane separation unit to obtain a retentate stream and a first permeate stream, wherein the retentate stream comprises hydrogen sulfide, wherein the permeate stream comprises carbon dioxide; introducing the retentate stream to a sulfur recovery unit; processing the retentate stream in the sulfur recovery unit to produce a sulfur stream and a tail gas stream, wherein the sulfur stream comprises liquid sulfur; introducing the permeate stream to an amine absorption unit; and processing the permeate stream in the amine absorption unit to produce an enriched carbon dioxide stream.

This invention relates to processes for selective removal of contaminants from effluent gases. A sulfur dioxide absorption/desorption process for selective removal and recovery of sulfur dioxide from effluent gases utilizes a buffered aqueous absorption solution comprising weak inorganic or organic acids or salts thereof, to selectively absorb sulfur dioxide from the effluent gas. Absorbed sulfur dioxide is subsequently stripped to regenerate the absorption solution and produce a sulfur dioxide-enriched gas. A process for simultaneous removal of sulfur dioxide and nitrogen oxides (NO.sub.x) from effluent gases and recovery of sulfur dioxide utilizes a buffered aqueous absorption solution including a metal chelate to absorb sulfur dioxide and NO.sub.x from the gas and subsequently reducing absorbed NO.sub.x to form nitrogen. A process to control sulfate salt contaminant concentration in the absorption solution involves partial crystallization and removal of sulfate salt crystals.