An enrichment apparatus and process for enriching a hydrogen sulfide concentration in an acid gas stream to create a hydrogen sulfide rich stream for feed to a Claus. The enrichment apparatus comprises a hydrocarbon selective separation unit operable to separate the acid gas stream into a hydrocarbon rich stream and a purified acid gas stream, wherein the acid gas stream comprises hydrogen sulfide, carbon dioxide, and hydrocarbons, a hydrogen sulfide selective separation unit operable to separate the purified acid gas stream to create the hydrogen sulfide rich stream and a hydrogen sulfide lean stream, the hydrogen sulfide rich stream having a concentration of hydrogen sulfide, and the Claus unit operable to recover sulfur from the carbon dioxide lean stream. The enrichment apparatus can include a carbon dioxide selective separation unit in fluid communication with the hydrogen sulfide selective separation unit, operable to separate the hydrogen sulfide rich stream.

Plants, processes, and methods for reducing the H.sub.2S and CO.sub.2 contents of shale gasses from fields that produce shale gasses having varying H.sub.2S and CO.sub.2 contents are provided. Acid gas enters an absorber and is scrubbed using a lean physical solvent, producing a treated gas and a rich physical solvent. The H.sub.2S content of the treated gas is further reduced in an amine absorber, producing a pipeline gas and a semi-lean amine. The pipeline gas contains lower levels of H.sub.2S and CO.sub.2 than gas produced using a polishing bed. A physical solvent regeneration unit regenerates the lean physical solvent from the rich physical solvent for feeding into the absorption unit. An amine regeneration unit regenerates the lean amine from the semi-lean amine for feeding into the amine absorber. Contemplated plants may further comprise a Claus Unit or a Redox unit for oxidizing H.sub.2S to elemental sulfur.

A process for producing synthesis gas (syngas) comprising the endothermic reaction between CO.sub.2 and H.sub.2S, wherein the energetic supply is provided by the exothermic oxidation of a small portion of H.sub.2S to SO.sub.2 according to the following reaction scheme: R2: H.sub.2S+1.5O.sub.2.fwdarw.SO.sub.2+H.sub.2O said process being carried out according to the following overall theoretical reaction scheme R1, not taking into account the aforementioned exothermic reaction R2, R1: CO.sub.2+2H.sub.2S.fwdarw.CO+H.sub.2+S.sub.2+H.sub.2O wherein the amount of fed oxygen is comprised between 5% and 25% by volume over the total volume of fed reactants gaseous mixture.

An enrichment apparatus and process for enriching a hydrogen sulfide concentration in an acid gas stream to create a hydrogen sulfide rich stream for feed to a Claus. The enrichment apparatus comprises a hydrocarbon selective separation unit operable to separate the acid gas stream into a hydrocarbon rich stream and a purified acid gas stream, wherein the acid gas stream comprises hydrogen sulfide, carbon dioxide, and hydrocarbons, a hydrogen sulfide selective separation unit operable to separate the purified acid gas stream to create the hydrogen sulfide rich stream and a hydrogen sulfide lean stream, the hydrogen sulfide rich stream having a concentration of hydrogen sulfide, and the Claus unit operable to recover sulfur from the carbon dioxide lean stream. The enrichment apparatus can include a carbon dioxide selective separation unit in fluid communication with the hydrogen sulfide selective separation unit, operable to separate the hydrogen sulfide rich stream.

A feed stream including hydrogen sulfide is heated to a preheat temperature. At least a portion of the hydrogen sulfide in the feed stream is converted into hydrogen and sulfur to form a mixed product stream including the hydrogen, the sulfur, and a remaining, unconverted portion of the hydrogen sulfide. The preheat temperature is a temperature that is sufficiently hot to maintain a desired reaction temperature while converting at least the portion of the hydrogen sulfide in the feed stream into hydrogen and sulfur. At least a portion of the mixed product stream is cooled to a specified temperature at which recombination of the hydrogen and the sulfur into hydrogen sulfide is prevented. Cooling at least the portion of the mixed product stream includes condensing at least a portion of the sulfur to form a sulfur stream.

An embodiment described herein provides a method of treating a gas stream, where the method includes: flowing the gas stream containing H.sub.2S and CO.sub.2 into a plasma reactor; igniting a plasma in the plasma reactor containing the gas stream; decomposing the H.sub.2S to generate H.sub.2 and elemental sulfur in the plasma generating a product gas stream; condensing the elemental sulfur from the product gas stream as a liquid; and separating the H.sub.2 from the product gas stream.