A system and method for simultaneously removing water and acid gases from methane in a single process without requiring dehydration prior to acid gas removal. A feed stream comprising these components and little or no hydrocarbons heavier than methane is separated in a series of separators, including an absorber column using methanol as an absorber. A treated methane stream comprising at least 90%, more preferably at least 95%, most preferably at least 99%, of the methane from the feed stream and an acid gas waste stream comprising less than 10%, more preferably less than 5%, most preferably less than 1%, of the methane from the feed stream are produced. Using methanol as a physical solvent allows removal of water and acids gases in a single step using substantially less energy than conventional separation methods. The system and method are particularly useful in treating landfill gas feed streams.

The invention provides a process for regenerating a liquid absorbent, comprising: contacting the liquid absorbent with a hydrophobic medium, wherein the liquid absorbent comprises at least one amine of Formula (I) and degradation product thereof comprising at least one imine of Formula (II), wherein each Ar is independently an aromatic group and each R is independently selected from hydrogen, an organyl group and NH.sub.2; and selectively extracting the degradation product into or through the hydrophobic medium.

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Methods of reducing acid gas from a stream, comprising contacting the stream with a solvent system comprising a glycerol derivative are described herein. Disclosed herein is a composition comprising a glycerol derivative and an acid gas. A method for sweetening a natural gas stream comprising contacting a solvent system comprising a glycerol derivative with a natural gas stream is described herein.

A system for regeneration of acidic gas solvent, the system comprising; a regeneration cell having a solvent chamber arranged to receive a solvent flow, and an internal chamber arranged to receive a steam flow; said regeneration cell including a gas permeable membrane separating the solvent chamber and internal chamber; wherein the regeneration cell is arranged to vent acidic gas stripped from the solvent by the steam.

The present invention relates to a process for removing acid compounds contained in a gaseous effluent which consists in bringing a gaseous effluent into contact, in the absorption column, with an absorbent solution comprising water, between 20% and 28% by weight of pentamethyldipropylenetriamine and between 5% and 35% by weight of N-methyldiethanolamine.

The present disclosure relates to methods and systems for sweetening natural gas may utilize a water wash to achieve a reduction in raw natural gas stream contaminants (e.g., particulate contaminants and/or chemical contaminants) and/or to recover solvent used for removing H.sub.2S and CO.sub.2 from the natural gas. For example, a method may include contacting a first natural gas stream with a first water stream in a co-current contacting system to produce a second natural gas stream and a second water stream, wherein the first natural gas stream comprises natural gas, an acid gas, and a contaminate, and wherein a concentration of the contaminate in the second natural gas stream is less than a concentration of the contaminate in the first natural gas stream; and removing at least a portion of the acid gas from the second natural gas stream.

Certain implementations of amine sweetening of flash gas are described. Flash gas including acid gas is flowed from a flash drum through a column section connected to the flash drum. A lean amine stream is flowed through the column section. The lean amine stream is configured to treat the acid gas flowed from the flash drum through the column section. A quantity of the lean amine stream flowed through the column section is controlled based, in part, on a rate at which the flash gas including the acid gas is flowed from the flash drum through the column section and a concentration of the acid gas in the flash gas.

A scrubbing solution for removing contaminants, including particularly hydrogen sulfide, from a fluid. The scrubbing solution includes at least one scrubbing reagent which has a primary or secondary amine and an acid, which may be phosphoric acid. The fluid being scrubbed is passed through the scrubbing solution. The contaminants react with the scrubbing reagent securing them in the scrubbing solution. The fluid being scrubbed and the scrubbing solution are then separated. The scrubbing solution is heated and, if the scrubbing solution is under pressure, the pressure is reduced. The acid facilitates thorough removal of the contaminants, and especially the hydrogen sulfide, from the scrubbing solution. The scrubbing solution is then ready for reuse. Because the scrubbing solution is rendered substantially free of hydrogen sulfides, it can absorb other sulfide contaminants that might not otherwise be absorbed.

Disclosed is an adsorbent containing a metal oxide for adsorption of hydrogen sulfide in biogas, and a biogas purification system using the same.

An integrated amine and redox gas treatment system is configured to treat an influent hydrocarbon containing stream. The system includes a reduction oxidation unit connected directly downstream of an amine unit. The amine unit is configured to separate the influent fluid stream into a first amine effluent stream including hydrocarbons and a second amine effluent stream including a connection pressure and comprising CO.sub.2. The reduction oxidation unit is configured to receive the second amine effluent stream from the amine unit and operate at the connection pressure while releasing a reduction oxidation effluent stream including purified CO.sub.2 The connection pressure includes a single pressure or a plurality of pressures at which both the amine unit and the reduction oxidation unit are configured to operate.