In a first stage of a methane conversion system, at least some methane (CH.sub.4) in an input gas flow stream can be converted into C.sub.2 hydrocarbons, hydrogen gas (H.sub.2), and aromatics to provide a first processed stream. The conversion can be direct non-oxidative methane conversion (DNMC). At least some of the aromatics can be removed from the first processed stream to provide a second processed stream. In a second stage of the methane conversion system, at least some of the H.sub.2 can be removed from the second processed stream to provide a recycle stream. The recycle stream can be returned to the first stage of the methane conversion system for further conversion of methane and removal of aromatics and H.sub.2 products.

An H.sub.2-rich fuel gas stream can be advantageously produced by reforming a hydrocarbon/steam mixture in to produce a reformed stream, followed by cooling the reformed stream in a waste-heat recovery unit to produce a high-pressure steam stream, shifting the cooled reformed stream a first shifted stream, cooling the first shifted stream, shifting the cooled first shifted stream to produce a second shifted stream, cooling the second shifted stream, abating water from the cooled second shifted stream to obtain a crude gas mixture stream comprising H.sub.2 and CO.sub.2, and recovering a CO.sub.2 stream from the crude gas mixture stream. The H.sub.2-rich stream can be advantageously combusted to provide thermal energy needed for residential, office, and/or industrial applications including in the H.sub.2-rich fuel gas production process. The H.sub.2-rich fuel gas production process can be advantageously integrated with an olefins production plant comprising a steam cracker.

The present invention relates to an extraction unit for extracting hydrogen from a gas mixture, including a tube or vessel, including a transit channel for passing a gas mixture in a feed-through direction from a receiving opening to a dispensing opening, which tube or vessel is arranged to be received in-line in a gas transport pipe, at least one membrane-electrode assembly arranged in the tube or vessel with at least one anode, a membrane and a cathode. The assembly is arranged such that an anode surface faces the transit channel and that a cathode surface faces away from the transit channel to a drain separated from the feed-through channel. The anode and the cathode are provided with a connector for an electrical voltage source.

The invention provides a process for separating hydrogen from a gaseous feed stream in a polymerisation process, comprising the steps i) polymerising an olefin monomer and optionally at least one olefin comonomer, in the presence of a solvent optionally in the presence of hydrogen, so as to form a polymerisation reaction mixture comprising a polyolefin polymer, unreacted monomer(s), solvent and hydrogen; ii) separating said polyolefin polymer from said unreacted monomer(s), solvent and hydrogen; iii) feeding said unreacted monomer(s) and hydrogen to a condenser so as to form said gaseous feed stream; iv) contacting said gaseous feed stream with a hydrogen separating membrane so as to form a hydrogen-rich gaseous stream and a hydrogen-lean gaseous stream.

Provided are a hydrogen purification device and a hydrogen purification method whereby hydrogen having a high purity can be purified at a high yield from a starting gas. The hydrogen purification device comprises: a starting gas source that supplies a starting gas, said starting gas containing hydrogen molecules and/or a hydride, to a discharge space; a plasma reactor that defines at least a part of the discharge space; a hydrogen flow channel that is connected to the discharge space; and leads out purified hydrogen from the starting gas source; a hydrogen separation membrane that partitions the discharge space from the hydrogen flow channel defines at least a part of the discharge space by one surface thereof and defines at least a part of the hydrogen flow channel by the other surface thereof; an electrode that is positioned outside the discharge space; and an adsorbent that is filled in the discharge space and adsorbs the starting gas. In the hydrogen purification method according to the present invention, the starting gas is adsorbed by the adsorbent in the discharge space. Hydrogen molecules, which have been desorbed from the adsorbent by discharge, are allowed to penetrate through the hydrogen separation membrane 4 and led out into the hydrogen flow channel.

The invention includes a gas processing system for transforming a hydrocarbon-containing inflow gas into outflow gas products, where the system includes a gas delivery subsystem, a plasma reaction chamber, and a microwave subsystem, with the gas delivery subsystem in fluid communication with the plasma reaction chamber, so that the gas delivery subsystem directs the hydrocarbon-containing inflow gas into the plasma reaction chamber, and the microwave subsystem directs microwave energy into the plasma reaction chamber to energize the hydrocarbon-containing inflow gas, thereby forming a plasma in the plasma reaction chamber, which plasma effects the transformation of a hydrocarbon in the hydrocarbon-containing inflow gas into the outflow gas products, which comprise acetylene and hydrogen. The invention also includes methods for the use of the gas processing system.

The invention includes a gas processing system for transforming a hydrocarbon-containing inflow gas into outflow gas products, where the system includes a gas delivery subsystem, a plasma reaction chamber, and a microwave subsystem, with the gas delivery subsystem in fluid communication with the plasma reaction chamber, so that the gas delivery subsystem directs the hydrocarbon-containing inflow gas into the plasma reaction chamber, and the microwave subsystem directs microwave energy into the plasma reaction chamber to energize the hydrocarbon-containing inflow gas, thereby forming a plasma in the plasma reaction chamber, which plasma effects the transformation of a hydrocarbon in the hydrocarbon-containing inflow gas into the outflow gas products, which comprise acetylene and hydrogen. The invention also includes methods for the use of this gas processing system.

A process for producing low or no carbon intensity hydrogen. In one embodiment, the process includes the step of pretreating a hydrocarbon gas stream. The pretreated hydrocarbon gas stream is fed into a reformer. The pretreated hydrocarbon gas steam is heated in the reformer to produce a synthesis gas stream and a flue gas stream. The flue gas stream is fed to a waste heat recovery section. Waste heat is recovered to increase the thermal efficiency of the process. The synthesis gas stream is fed to a shift gas reactor. Carbon monoxide from the synthesis gas stream in the shift gas reactor is converted to produce hydrogen and carbon dioxide. The carbon dioxide is separated from the synthesis gas stream and the hydrogen is separated. In another embodiment, the carbon dioxide is captured following the hydrogen separation. In another embodiment, the carbon dioxide is captured from the flue gas.

A method for decreasing the SFFC of a steam reforming plant, including establishing a base operating mode. Then modifying the base operating mode by introducing the shift gas stream into a solvent based, non-cryogenic separator prior to introduction into the pressure swing adsorption and introducing the compressed hydrogen depleted off-gas stream in a membrane separation unit, wherein the membrane is configured to produce the hydrogen enriched permeate stream at a suitable pressure to allow the hydrogen enriched permeate stream to be combined with carbon dioxide lean shift gas stream, prior to introduction into the pressure swing adsorption unit without requiring additional compression. Thereby establishing a modified operating mode. Wherein said pressure swing adsorption unit has a modified overall hydrogen recovery. Wherein said modified operating mode has a modified hydrogen production, a modified hydrogen production unit firing duty, a modified SCO2e, and a modified SFFC.

A method for decreasing the SFFC of a steam reforming plant, including establishing a base operating mode. Then modifying the base operating mode by introducing the shift gas stream into a solvent based, non-cryogenic separator prior to introduction into the pressure swing adsorption and introducing the compressed hydrogen depleted off-gas stream in a membrane separation unit, wherein the membrane is configured to produce the hydrogen enriched permeate stream at a suitable pressure to allow the hydrogen enriched permeate stream to be combined with carbon dioxide lean shift gas stream, prior to introduction into the pressure swing adsorption unit without requiring additional compression. Thereby establishing a modified operating mode. Wherein said pressure swing adsorption unit has a modified overall hydrogen recovery. Wherein said modified operating mode has a modified hydrogen production, a modified hydrogen production unit firing duty, a modified SCO2e, and a modified SFFC.