Composite materials and methods of preparing C0.sub.2 capture include: (1) a porous solid support comprising a plurality of porous channels; and (2) a nucleophilic source associated with the porous channels of the porous solid support. The nucleophilic source is capable of converting the captured C0.sub.2 to poly(C0.sub.2). Methods of capturing C0.sub.2 from an environment include associating the environment with the aforementioned composite materials to lead to the capture of C0.sub.2 from the environment. Such methods may also include a step of releasing the captured C0.sub.2 from the composite material. The associating step comprises a conversion of the captured C0.sub.2 to poly(C0.sub.2) in the composite material. A releasing step may also include a depolymerization of the formed poly(C0.sub.2).

Disclosed herein is a composite hollow fiber polymer membrane including a porous core layer and a selective sheath layer. The porous core layer includes a polyamide-imide polymer, or a polyetherimide polymer, and the selective sheath layer includes a polyimide polymer, which is prepared from monomers A, B, and C. The monomer A is a dianhydride of the formula ##STR00001##
wherein X.sub.1 and X.sub.2 are independently halogenated alkyl group, phenyl or halogen and R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6 are independently H, alkyl, or halogen. The monomer B is a diamino cyclic compound without a carboxylic acid functionality and the monomer C is a diamino cyclic compound with a carboxylic acid functionality. The polyimide polymer further includes covalent ester crosslinks. Also disclosed herein is a method of making the composite polymer membrane and a process for purifying natural gas utilizing the composite polymer membrane.

The present invention relates to a method of controlling a gas separation plant, to a plant thus controlled and also to its use for separation of gas mixtures, especially in the processing of biogas or natural gas, or syngas.

A source gas introduction line for introducing source gas containing CO.sub.2, a first membrane separator for membrane-separating CO.sub.2 from source gas, a first permeable gas discharge line for discharging first permeable gas permeated by membrane separation of the first membrane separator, a first non-permeable gas discharge line for discharging first non-permeable gas not permeated by membrane separation of the first membrane separator, a second membrane separator provided at a downstream side of the first membrane separator and for further membrane-separating CO.sub.2 from the first non-permeable gas, a second permeable gas discharge line for discharging second permeable gas permeated by membrane separation of the second membrane separator, a second permeable gas return line branched from a part of the second permeable gas discharge line and for returning the second permeable gas to a source gas side, and a CO.sub.2 concentration meter are included.

A process for separating components or a fluid mixture using membranes comprising a selective layer made from copolymers of an amorphous per fluorinated dioxolane and a fluorovinyl monomer. The resulting membranes have superior selectivity performance for certain fluid components of interest while maintaining fast permeance compared to membranes prepared using conventional perfluoropolymers, such as Teflon® AF, Hyflon® AD, and Cytop®.

Ancillary embodiments and modifications to a homogenizer unit (“PPH”), and methods of use directed to purification of biogas or other raw methane streams. The apparatus includes a homogenizer body, one or more stream inlets (for the raw methane), one or more chilled water inlets, a mixing zone where the water stream is commingled with the raw methane stream, and a venturi immediately downstream from the mixing zone such that the commingled streams are pulled into the venturi resulting in homogenization. The PPH components are insulated to maintain the chilled water of the various streams at a cooled, below ambient temperature, increasing dissolution of the contaminant gases into the chilled water, and producing a purified methane stream including little or no H.sub.2S and CO.sub.2.

A system including biogas purification and provides biogas as feedstock to a solid oxide fuel cell. The biogas purification treatment process provides a polished biogas that is substantially free of carbonyl sulfides and hydrogen sulfide. The system uses a biogas treatment apparatus, that includes apparatus such as a packed columns, comprising copper oxide or potassium permanganate packing material, and an activated carbon component configured to treat the biogas by polishing it to remove carbonyl sulfides and deleterious trace residues, such as hydrogen sulfide, that were not removed by any prior bulk H2S removal steps. In addition, an oil removal device is used to remove any entrained fine oil droplets in the biogas. A polished biogas having in the range of 60% methane is charged to the fuel cell. Electricity generated may be fed into a grid or used directly as energy to charge electrical-powered vehicles, for example. Energy credits are tracked in real time and are appropriately assigned.

A facility and method for membrane permeation treatment of a feed gas flow containing at least methane and carbon dioxide that includes a compressor, a gas analyser, at least one valve, and first, second, third, and fourth membrane separation units for separation of CO.sub.2 from CH.sub.4 to permeates enriched in CO.sub.2 and retentates enriched in CH.sub.4, respectively. A pressure of the feed gas flow is adjusted according to a CH.sub.4 concentration of the second retentate.

A set of process equipment for use in an enhanced oil recovery (EOR) process comprises first piping, a dehydrator, second piping, and a natural gas liquids recovery column. The first piping is configured to receive a wet carbon dioxide recycle stream from a recovery well. The dehydrator is configured to receive the wet carbon dioxide stream from the first piping and configured to dehydrate the wet carbon dioxide recycle stream using ethylene glycol to produce a dry carbon dioxide recycle stream. The second piping is configured to receive the dry carbon dioxide recycle stream from the dehydrator. The natural gas liquids recovery column is configured to receive the dry carbon dioxide recycle stream from the second piping and configured to separate the dry carbon dioxide recycle stream into a carbon dioxide reinjection stream and a natural gas liquids stream.

A system for high-value utilization of organic solid waste includes an anaerobic digestion unit, a biogas measurement and collection unit and a methane purification and liquefaction unit. The anaerobic digestion unit includes an organic solid waste pretreatment system and an anaerobic digestion device. The biogas measurement and collection unit includes a gas flow meter and a high-pressure biogas collection device. The methane purification and liquefaction unit includes a high-pressure separation tank, a liquefaction pretreatment system, a heavy hydrocarbon and benzene removal device, a two-stage rectification system, a low-temperature pressure liquid storage tank device and a buffer storage tank. The organic solid waste undergoes an anaerobic digestion treatment to produce methane followed by collection, purification and liquefaction.