Membrane-based hydrogen purifiers having graphite frame members. The purifiers include a hydrogen-separation membrane module with at least one membrane cell containing at least one hydrogen-selective membrane, which includes a permeate face and an opposed mixed gas face, and a fluid-permeable support structure that physically contacts and supports at least a central region of the permeate face. The membrane cell further includes a permeate-side frame member and a mixed gas-side frame member. The permeate-side frame member is interposed between the hydrogen-selective membrane and the fluid-permeable support structure to physically contact a peripheral region of the permeate face and a peripheral region of the fluid-permeable support structure. The mixed gas-side frame member physically contacts a peripheral region of the mixed gas face. At least one of the permeate-side frame member and the mixed gas-side frame member is a graphite frame member.

A gas separation apparatus includes a separation membrane module including at least one gas separation membrane element in a housing, a casing for blocking external air, and a heat source unit for adjusting a temperature of a heat medium with which the casing is filled. The casing holds greater than or equal to two separation membrane modules.

An apparatus (1) for supplying a gas mixture to a patient, having a gas inlet line (30) with a gas inlet orifice (30a) that splits into a first gas line (31) and a second gas line (32); at least one permeation module (33) arranged on the second gas line (32), the said permeation module (33) having a feed port (33a) in fluidic communication with the second gas line (32), a retentate port (33b) and a permeate port (33c); a third gas line (34) in fluidic communication with the retentate port (33b) of the permeation module (33); a fourth gas line (35) in fluidic communication with the permeate port (33c) of the permeation module (33), and coupling fluidically to the said first gas line (31); and a source (360) of air in fluidic communication with the first gas line (31) and the fourth gas line (35).

Facility and method for membrane permeation treatment of a feed gas stream containing at least methane and carbon dioxide including first, second, and third membrane separation units each including at least one membrane that is more permeable to carbon dioxide than to methane, wherein a permeate from the first membrane separation unit is fed to the third membrane separation unit and a retentate from the first membrane separation unit is fed to the second membrane separation unit. A compressor B adjusts the third-permeate suctioning pressure as a function of the feed gas stream pressure and the second retentate methane concentration.

A natural gas processing system is mounted on a mobile platform that is transported to a natural gas source, such as a well. The system supplies retentate gas to operate multi-fuel engines for wellfield equipment such as pumps, compressors, and drills. A liquid drain discharges contaminants. A separator, first and second coalescing filters, and a particulate filter remove particulate matter and fluid contaminant matter from the natural gas. A dryer removes water vapor from the natural gas. Dual membranes separate the natural gas into a retentate gas and a permeate gas. A first heat exchanger adjusts temperature of the natural gas entering the membranes. A second heat exchanger adjusts temperature of the retentate gas output. A thermoelectric generator powered by the natural gas supplies process electricity. A process control monitors and controls the natural gas processing system, including pressure control valves, temperature control valves, and emergency shutdown systems. An instrument gas supply with an accumulator supplies gas pressure to operate pneumatic valves and instruments.

A device and method for carbon dioxide capture using circumscribed hollow membranes is disclosed. The device includes a hollow membrane unit having an inner conduit composed of a vapor membrane, and an outer conduit having an inside surface circumscribing the inner conduit forming a lumen. The outer conduit includes a CO.sub.2 pump membrane. The device also includes a mechanical pump maintaining a pressure differential between the lumen and the atmosphere, providing a product stream of CO.sub.2-rich gas from the lumen. The vapor membrane is sufficiently hydrophobic and porous to contain liquid water while also allowing water vapor formed by evaporation to pass through into the lumen. As water vapor passes from the lumen to the atmosphere through the CO.sub.2 pump membrane, a carbon concentration gradient is formed and maintained across the CO.sub.2 pump membrane. The carbon concentration gradient actively pumps CO.sub.2 out of the atmosphere and into the lumen.

An apparatus and process for separating a gas mixture is disclosed. The apparatus includes a first membrane stage, a second membrane stage, and a third membrane stage. The first membrane stage includes a first gas separation membrane configured to separate the gas mixture into a first retentate stream and a first permeate stream. The second membrane stage includes a second gas separation membrane configured to separate the first permeate stream into a second retentate stream and a second permeate stream. The second retentate stream of the second membrane stage is recycled back to connect with the first retentate stream to form a mixed fluid stream. The third membrane stage includes a third gas separation membrane configured to separate the mixed fluid stream into a third retentate stream and a third permeate stream, and the third retentate stream is configured to be withdrawn as a product or discarded.

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.

An apparatus and process for separating a gas mixture is disclosed. The apparatus includes a plurality of membrane separation stages comprising a first membrane stage, a second membrane stage, and a third membrane stage. Each of the first, second, and third membrane stages are designed to separate a gas stream provided to them into a permeate stream and a retentate stream. The retentate stream provided from the third membrane stage is configured to be withdrawn as a product, further processed, or discarded. The apparatus further includes a gas transport device with an inlet in communication with the gas mixture and an outlet in communication with the first membrane stage. The controller is in communication with at least one measuring device, and the controller adapts a behavior of the gas transport device in response to a measurement of the at least one measuring device.

A biogas upgrading system can include a multiple stage membrane system that is configured to remove oxygen so that the biogas is upgraded to have a higher concentration of methane, a pre-selected oxygen (O.sub.2) concentration (e.g. less than or equal to 0.2 mol %, etc.), and a pre-selected carbon dioxide (CO.sub.2) concentration (e.g. less than or equal to 5 mol %, etc.). The membrane system can be configured to reject O.sub.2 by utilizing a low CO.sub.2/O.sub.2 selectivity that is within a pre-determined range (e.g. less than 5 or less than 4.5). In some embodiments, the upgraded biogas that is output from the system can be entirely made up of methane, carbon dioxide, and oxygen. In other embodiments, the biogas can be almost entirely composed of these components along with a small amount of nitrogen and a trace amount (e.g. less than or equal to 0.2%-0.1%, etc.) of other components.