A process for capturing carbon dioxide in which an exhaust stream containing carbon dioxide is cooled by a plurality of stages of indirect heat exchange to produce a cooled exhaust stream, compressed over a plurality of stages of compression, and separated to produce a CO2-enriched stream and a CO2-depleted stream. The CO2-enriched stream is dehydrated by contacting the CO2-enriched stream with a regenerated desiccant to produce a CO2 product stream and a spent desiccant. The CO2-depleted stream is heated by indirect heat exchange against the exhaust stream to produce a hot CO2-depleted stream, while a portion of the CO2-depleted stream is extracted from an interstage of the plurality of stages of indirect heat exchange to regenerate the spent desiccant. The hot CO2-depleted stream is expanded over a plurality of stages of expansion to drive the compression of the cooled exhaust, thereby producing an expanded CO2-depleted stream.

An oxygen concentrator (100) may have a moisture conditioning system. In some implementations, the concentrator includes a compressor to induce feed gas into the concentrator. A first pathway may receive the feed gas from the compression system. The first pathway may be configured to draw moisture to produce moisture reduced feed gas. The first pathway may lead the moisture reduced feed gas to sieve bed(s) which produce oxygen enriched air with the moisture reduced feed gas. An accumulator may be configured to receive the produced oxygen enriched air from the sieve bed(s). A second pathway from the accumulator may apply the drawn-out moisture to the produced enriched air to produce humidified enriched air. A third pathway may transfer the drawn-out moisture from the first pathway to the second pathway. An outlet coupled with the second pathway may release the humidified enriched air from the concentrator for a user.

An apparatus and method for flow management and CO.sub.2-recovery from a CO.sub.2 containing hydrocarbon flow stream, such as a post CO.sub.2-stimulation flowback stream. The apparatus including a flow control zone, a gas separation zone, a pretreatment zone, and a CO.sub.2-capture zone. The CO.sub.2-capture zone is in fluid communication with the pretreatment zone to provide CO.sub.2-capture from a pretreated flowback gas stream and output a captured CO.sub.2-flow stream. The CO.sub.2-capture zone includes a first CO.sub.2-enricher and at least one additional CO.sub.2 enricher disposed downstream of the first CO.sub.2 enricher and in cascading relationship to provide a CO.sub.2-rich permeate stream, the CO.sub.2-capture zone further including at least one condenser to condense the enriched CO.sub.2-stream and output the captured CO.sub.2-flow stream.

An environment control system utilizes oxygen and humidity control devices that are coupled with an enclosure to independently control the oxygen concentration and the humidity level within the enclosure. An oxygen depletion device may be an oxygen depletion electrolyzer cell that reacts with oxygen within the cell and produces water through electrochemical reactions. A desiccating device may be g, a dehumidification electrolyzer cell, a desiccator, a membrane desiccator or a condenser. A controller may control the amount of voltage and/or current provided to the oxygen depletion electrolyzer cell and therefore the rate of oxygen reduction and may control the amount of voltage and/or current provided to the dehumidification electrolyzer cell and therefore the rate of humidity reduction. The oxygen level may be determined by the measurement of voltage and a limiting current of the oxygen depletion electrolyzer cell. The enclosure may be a food or artifact enclosure.

A flow plate for a humidifier, having flow fields on both mutually opposite flat sides of the flow plate is described. The flow plate proposed here has a multiplicity of through-openings, wherein the through-openings are designed such that a perpendicular projection of the through openings onto a plane oriented parallel to the plane of the flat surface of the flow plate has a non-vanishing area, so that gas passing through the through-openings effects, at least in part, mixing of a gas guided in the flow fields perpendicular to the plane of the flat surface of the flow plate. The through-openings improve the power of the humidifier, thus permitting a lower number of flow plates and therefore a more lightweight and more compact design.

Apparatus and methods are described, including a water trap (28) that includes an inlet portion (40), via which a mixture of gas and water is configured to enter the water trap, and an outlet portion (42), via which the gas is configured to exit the water trap, the inlet portion and the outlet portion being formed separately from one another and being coupled to one another, such as to form a tube (44) that defines a longitudinal axis and that defines an internal hollow volume through which the gas is configured to flow. A membrane filter (46) is disposed in a flat configuration within the tube, between the inlet portion and the outlet portion, such that the membrane filter is substantially parallel to the longitudinal axis of the tube, the membrane filter being configured to prevent the water from passing therethrough. Other applications are also described.

A dehumidification mechanism for an appliance includes a blower that delivers humid process air along an airflow path. A drum is positioned along the airflow path. A condensing apparatus dehumidifies the humid air to define dehumidified air. A membrane has a plurality of nanopores that define a portion of the airflow path within the condensing apparatus. The humid air is delivered along the membrane having the plurality of nanopores and the nanopores operate through capillary condensation to dehumidify the humid air and separate condensate away from the humid air to define the dehumidified air. The condensate removed by the nanopore membrane is delivered away from the airflow path and to a condensate collection area within the appliance.

A method relating to a copolymer containing rigid polyamides blocks and flexible blocks including, relative to the total weight of the copolymer: from 55% to 90% by weight of flexible blocks, including at least 35% by weight from polyethylene glycol; from 10% to 45% by weight of rigid polyamide blocks, in which the mean carbon content of the repeating units of the polyamide blocks is greater than or equal to 7. A method also relating to a process for preparing such a copolymer, to a membrane including such a copolymer and to a process for preparing such a membrane.

The invention relates to a process for dehumidifying a moist gas mixture. The invention further relates to an apparatus for dehumidifying a moist gas mixture and to the use of said apparatus in the process according to the invention.

Disclosed are various turbulent, corrosion-resistant heat exchangers used in desiccant air conditioning systems.