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.

Devices, systems, and methods for determining gas characteristics to monitor transformer operation include extracting gas from transformer fluid for analysis.

A device for separating a gas, such as air, into components, includes a plurality of modules, each module having one or more polymeric membranes capable of gas separation. A set of valves, pipes, and manifolds together arrange the modules in one of two possible configurations. In a first configuration, the modules are arranged in parallel. In a second configuration, the modules are divided into two groups which are arranged in series. The device can be switched from parallel to series, or from series to parallel, simply by changing the positions of a small number of valves, typically three valves. The device can therefore produce gas either of higher purity, or moderate purity, depending on the settings of the valves. The device also includes improved structures for connecting the modules to inlet and outlet manifolds, and also includes devices for temporarily isolating one or more modules from the system.

Devices, systems, and methods for determining gas characteristics to monitor transformer operation include extracting gas from transformer fluid for analysis.

Described are porous sintered bodies and methods of making porous sintered bodies by steps that include an injection molding step.

The CO.sub.2 separation system performs, when the internal combustion engine is operating and the vehicle is travelling, a first mode wherein exhaust gas generated by the internal combustion engine is introduced to a CO.sub.2 supply side of a first CO.sub.2 separation device via a first CO.sub.2 supply side introduction flow path, and air from outside the vehicle is introduced to a CO.sub.2 permeation side of the first CO.sub.2 separation device via a first CO.sub.2 permeation side introduction flow path using travelling wind, whereby CO.sub.2 in the exhaust gas selectively permeates from the CO.sub.2 supply side to the CO.sub.2 permeation side of the first CO.sub.2 separation device through a CO.sub.2 permeable membrane of the first CO.sub.2 separation device using a difference in CO.sub.2 partial pressure between the CO.sub.2 supply side and the CO.sub.2 permeation side of the first CO.sub.2 separation device as a driving force.

Provided is a method for removing CO.sub.2 comprising: supplying a gas to be processed containing CO.sub.2, N.sub.2 and O.sub.2 to a feed side of a CO.sub.2/O.sub.2 selective permeation membrane within a temperature range of 15 C. to 50 C.; generating water vapor and supplying the water vapor to the CO.sub.2/O.sub.2 selective permeation membrane; selectively removing CO.sub.2 from the gas to be processed by permeating CO.sub.2 in the gas to be processed from the feed side to a permeate side of the CO.sub.2 selective permeation membrane selectively to O.sub.2 and N.sub.2 in the gas to be processed; and using a CO.sub.2 facilitated transport membrane having CO.sub.2/O.sub.2 selectivity and CO.sub.2/N.sub.2 selectivity within the temperature range as the CO.sub.2 selective permeation membrane, the CO.sub.2 facilitated transport membrane being configured with a hydrophilic polymer containing an amino acid and a deprotonating agent for preventing protonation of an amino group of the amino acid supported by a porous membrane, wherein a CO.sub.2 concentration in the gas to be processed is 3 mol % or less on a dry basis.

A method for capturing carbon dioxide from a carbon dioxide feed stream in which the carbon dioxide feed stream is dehydrated, cooled, and partially condensed. The partially condensed carbon dioxide stream is separated to form the carbon dioxide product stream. The carbon dioxide feed stream is produced by combusting a fuel stream with an oxygen-enriched gas stream with less than 92% purity.

A hydrogen gas producing apparatus includes a porous body (100) and a mixed gas source (300). The porous body (100) is permeable to hydrogen gas and carbon dioxide gas, and has a property of being more permeable to hydrogen gas than carbon dioxide gas. The mixed gas source (300) causes a mixed gas including carbon dioxide gas and hydrogen gas to flow into the porous body (100) under a condition that a pressure gradient represented by (P.sub.1P.sub.2)/L is below 50 MPa/m, where L represents the length of the porous body (100) in a direction in which the mixed gas permeates; P.sub.1 represents an inflow pressure of the mixed gas into the porous body (100); and P.sub.2 represents an outflow pressure thereof from the porous body (100).

A gas inerting system employs a carbon dioxide separation unit to remove carbon dioxide and water from an oxygen depleted gas stream generated from a catalytic oxidation unit and subsequently provides a nitrogen rich inerting gas to a fuel tank and/or to a cargo hold. A method of producing an inert gas passes an oxygen depleted gas stream from a catalytic oxidation unit through a carbon dioxide separation unit and provides a nitrogen rich inerting gas for fuel tank inerting and/or cargo hold fire suppression.