A method for removing hydrogen sulfide (H.sub.2S) from an acid gas comprises feeding the gas to a membrane separation unit, collecting the product gas from the membrane unit, heating the permeate stream to the necessary inlet temperature for catalytic oxidation of H.sub.2S and feeding the heated permeate stream to a catalytic oxidation unit, where H.sub.2S is oxidized to SO.sub.2. The heating of the permeate stream is accomplished by using a fraction of the feed gas to heat the permeate stream in a separate heater or by using a steam-fired heater. The method is especially suited for use on an off-shore facility.

A process for altering the composition of a feed gas containing H.sub.2S equivalents is disclosed. The process comprises (a) contacting the feed gas with a solid adsorbent at a temperature of 250-500° C., to obtain a loaded adsorbent, (b) purging the loaded adsorbent with a purge gas comprising steam, thus producing a product stream which typically contains substantially equal levels of CO.sub.2 and H.sub.2S. The process further comprises a step (c) of regenerating the purged adsorbent by removal of water. The adsorbent comprises alumina and one or more alkali metals, such as potassium oxides, hydroxide or the like.

Disclosed are a carbon dioxide absorbent composition in which an N-alkylaminoalkanol; a polyhydroxyamine-based compound; and ethylenediamine and/or diethylenetriamine are mixed, a method for preparing the same, and a method and an apparatus for carbon dioxide absorption/separation using the same. Since the carbon dioxide absorbent according to the present disclosure has superior carbon dioxide absorption capacity and remarkably lower absorbent recycling temperature as compared to the existing absorbents such as monoethanolamine, etc., total energy consumption in the capturing process can be reduced greatly. In addition, since carbon dioxide is recovered at low recycling temperature, contamination by water or absorbent vapor may be prevented.

A wastewater treatment plant includes an anaerobic membrane bioreactor, AnMBR, unit configured to receive wastewater and to produce (1) a final permeate and (2) a gas; an oxidation disinfection unit configured to receive the final permeate and to remove biological and chemical contaminants from the final permeate to generate a final effluent; and an energy recovery unit configured to receive the gas from the AnMBR unit and generate electrical energy. The wastewater treatment plant does not use chlorination.

The present invention relates to a gas-filtering system (1000, 3000, 4000, 5000, 6000) comprising: an input (1100) for the gas, a reactor (1301, 1302, 1303) for filtering the gas at the input (1100) and thus obtaining a filtered gas, an output (1200) for the filtered gas, a vacuum generator (1401, 1402) for generating a vacuum inside the reactor (1301, 1302, 1303), where the vacuum generator (1401, 1402) is configured so as to apply a first predetermined vacuum value (VI) in a first vacuum phase (T2) and so as to apply a second predetermined vacuum value (V2) in a second vacuum phase (T3); the filtering system (1000, 3000, 4000) further comprising a flow controller (1501, 1502, 1503) connected at the output to the reactor (1301, 1302, 1303), where the flow controller (1501, 1502, 1503) is configured so as to block the introduction of the filtered gas into the reactor (1301, 1302, 1303) during the first vacuum phase (T2), and where the flow controller (1501, 1502, 1503) is configured so as to allow the introduction of the filtered gas and/or a second gas into the reactor (1301, 1302, 1303), starting from the output (1200) during the second vacuum phase (T3).

This disclosure relates to a process for removing acid gases from a gas stream enriched in acid gases, wherein: (a) the gas stream enriched in acid gases is contacted in an absorption zone with an absorption medium, wherein the absorption medium is an aqueous medium comprising an amine, to form a gas stream depleted in acid gases which comprises an entrained amine and an absorption medium enriched in acid gases; and (b) treating the gas stream depleted in acid gases which comprises an entrained amine in a first scrubbing zone with a first scrubbing medium, wherein the first scrubbing medium is an aqueous medium comprising an amine, the amount of amine comprised by the scrubbing medium being about 0.1 to about 50.0 wt. %, wherein the aqueous medium is saturated with carbon dioxide such that at least 75 wt. % of the amine, based on the total amount of amine comprised by the aqueous medium, is in its carbamate or carbonate form, to form a gas stream depleted in acid gases and in amine and a first scrubbing medium enriched in amine.

Disclosed are metal organic frameworks (MOFs) for adsorbing guest species, methods for the separation of gases using the MOFs, and systems comprising the MOFs. The MOFs comprise a plurality of secondary building units (SBUs), each SBU comprising a repeating unit of one metal cation connected to another metal cation via a first moiety of an organic linker; a layer of connected adjacent SBUs in which a second moiety of the linker in a first SBU is connected to a metal cation of an adjacent SBU, and wherein adjacent layers are connected to each other via linker-to-linker bonding interactions

The invention relates to a method for membrane permeation of a gas flow including methane and carbon dioxide, wherein said gas flow is cooled to a temperature of 0° C. to −60° C. before being fed into a membrane separation unit.

The present disclosure is directed to methods for treating an organic material, including the steps of transporting the organic material into a first vessel; heating the organic material in the first vessel and applying a negative pressure to the organic material in the first vessel to a boiling point of the organic material, wherein the heat and negative pressure separates a portion of an ammonia from the organic material; removing the portion of the ammonia from the first vessel; transporting the removed portion of the ammonia from the first vessel to an acid solution in a second vessel; and separating a portion of the ammonia from the acid solution.

The present invention provides a method for separating high purity methane gas from biogas, which comprises the steps of: compressing and cooling biogas (step 1); and separating carbon dioxide by introducing the biogas compressed and cooled in step 1 into a four-stage polymer separation membrane system in which the residue stream of the first polymer separation membrane is connected to the second polymer separation membrane, the residue stream of the second polymer separation membrane is connected to the third polymer separation membrane, and the permeate stream of the second polymer separation membrane is connected to the fourth polymer separation membrane (step 2).