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 pressure measurement device, 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. The at least one valve adjusts the number of membranes combined and connected to the flow of gas entering into at least one of the membrane separation units as a function of the pressure recorded by the pressure measurement device.

An approach for separating a gaseous mixture includes a multi-stage membrane system in which a rubbery membrane is operated at a low temperature. Various streams are cooled and heated in a multi-fluid heat exchanger. In specific configurations, the multi-fluid heat exchanger is cooled by using no fluids other than fluids derived from the permeate and/or residue generated in the first membrane stage.

Known catalyst systems for the catalytic combustion of ammonia to form nitrogen oxides consist of a plurality of single- or multilayer catalyst gauzes warp-knitted, weft-knitted or woven from platinum-based noble metal wire, which, when arranged one behind the other in a fresh gas flow direction, form a front group of gauze layers and at least one downstream group of gauze layers arranged after the front group. To provide from this starting point a catalyst system for use in a medium-pressure plant for ammonia oxidation, with which a high service life and a high yield of the main product NO can be achieved, it is proposed that the front group comprises a gauze layer or a plurality of gauze layers made of a first, rhodium-rich noble metal wire, wherein the gauze layer or one of the gauze layers made of the rhodium-rich noble metal wire is a front gauze layer facing the fresh gas, and that the downstream group comprises gauze layers made of a second, rhodium-poor noble metal wire, wherein the rhodium content in the rhodium-rich noble metal wire is at least 7 wt. % and no more than 9 wt. % and is at least 1 percentage point higher than the rhodium content in the rhodium-poor noble metal wire

A gas separation system for controlling a concentration of a first gas species and a second gas species in an outlet gas comprises a splitter unit. The splitter unit comprises a gas membrane system having a gas inlet port. The gas inlet port is in fluid connection with an air intake. A membrane is a selective barrier and allows some things to pass through but stops others.

A method for separating a raw feed gas stream using a plurality of membrane separation stages includes separating a pressurized feed gas stream into a first nonpermeate stream and a first permeate stream, compressing the first permeate stream to form a compressed first permeate stream, separating the compressed first permeate stream into a second nonpermeate stream and a second permeate stream, separating the second permeate stream into a third nonpermeate stream and a third permeate stream, combining the third nonpermeate stream with a raw feed gas stream to form a combined feed stream, compressing the combined feed stream to form a compressed combined feed stream, and combining the second nonpermeate stream with the compressed combined feed stream to form the pressurized feed gas stream.

Disclosed herein is a system for recovering carbon monoxide from an industrial by-product gas, the system including a supply unit for supplying an industrial by-product gas containing carbon dioxide, nitrogen, carbon monoxide, and hydrogen, a first membrane separation unit including a separation membrane capable of allowing carbon dioxide and hydrogen to permeate, and receiving the industrial by-product gas supplied from the supply unit to allow carbon dioxide and hydrogen to permeate, and a second membrane separation unit including a polymer membrane in which a transition metal is supported, and receiving a gas remaining in the first membrane separation unit to allow carbon monoxide to permeate.

The invention relates to a process for recovering methane from digester biogas or landfill gas. More specifically, the invention pertains to a method for producing biomethane that removes impurities from a compressed digester biogas with staged membrane modules of at least two different types, to produce a biomethane having at least 94% CH.sub.4, below 3% of CO.sub.2, and below 4 ppm of H.sub.2S.

Systems and methods are provided that obtain the same or better level of performance by using lower operating flow rates, pressures and/or optimized flow distributions within the system. This extends the life of system components and lower energy consumption. In one embodiment, gas separation (or sieve) beds that are used to separate gaseous components are provided that have lower flow and pressure requirements compared to conventional beds. The sieve beds include, for example, a diffuser having low solid area in cross-section and maximum open area for flow while providing adequate mechanical properties to contain sieve material and support filter media. In another embodiment, systems and methods are provided having an indicator when a component has been serviced or repaired. This provides an indication whether the component has been tampered with in any manner. This allows the manufacturer to determine if the component was serviced, repaired, or tampered with outside the manufacturer's domain.

Systems and methods are provided that obtain the same or better level of performance by using lower operating flow rates, pressures and/or optimized flow distributions within the system. This extends the life of system components and lower energy consumption. In one embodiment, gas separation (or sieve) beds that are used to separate gaseous components are provided that have lower flow and pressure requirements compared to conventional beds. The sieve beds include, for example, a diffuser having low solid area in cross-section and maximum open area for flow while providing adequate mechanical properties to contain sieve material and support filter media. In another embodiment, systems and methods are provided having an indicator when a component has been serviced or repaired. This provides an indication whether the component has been tampered with in any manner. This allows the manufacturer to determine if the component was serviced, repaired, or tampered with outside the manufacturer's domain.

The present invention relates to a low-temperature membrane separation device and method for capturing carbon dioxide at a high concentration, in which a gas mixture is passed through a membrane unit to thus separate carbon dioxide. The membrane unit includes a membrane for capturing carbon dioxide and is connected to a feed gas line, a retentate gas line and a permeate gas line. The method includes a first separation step of passing the gas mixture through a first membrane unit and a second separation step of passing the permeation gas, which is discharged to the permeate gas line connected to the first membrane unit, through a second membrane unit. The second separation step is performed at a temperature that is lower than a temperature at which the first separation step is performed.