Abstract: In various embodiments, a support system includes a multi-layer cover sheet with a number of layers. In certain embodiments, a source to move air inside and outside the multi-layer cover sheet can be provided. The source can include a source of positive pressure or negative pressure.

Abstract: There is provided herein a dryer polymer substance including a hetero-phase polymer composition including two or more polymers wherein at least one of the two or more polymers include sulfonic groups, wherein the substance is adapted to pervaporate a fluid. The fluid may include water, water vapor or both. There is also provided herein a process for the preparation of a dryer polymer substance adapted to pervaporate a fluid (such as water, water vapor or both) the process includes mixing two or more polymers, wherein at least one of the two or more polymers may include groups which are adapted to be sulfonated, to produce a hetero-phase polymer composition and processing the polymer blend into a desired form.

Abstract: A method for producing a carbon membrane of the present invention is a production method where a carbon membrane obtained by subjecting a carbon-containing layer to thermal decomposition in an oxygen inert atmosphere while sending a gas mixture containing an oxidizing gas thereinto is thermally heated. The carbon membrane is subjected to a heating oxidation treatment with controlling the ratio of the flow rate of the gas mixture to the areas of the carbon membrane to 0.5 cm/min. or more to control (temperature ° C.)2×time (h)/10000, which is the relation between the temperature of the gas mixture and the flow time, to 9 to 32. This enables to obtain a carbon film which selectively separates alcohols having 2 or less carbon atoms from a liquid mixture of the alcohols having 2 or less carbon atoms and organic compounds having 5 to 9 carbon atoms.

Abstract: The instant invention generally provides polymer pi-bond-philic filler composite comprising a molecularly self-assembling material and a pi-bond-philic filler, and a process of making and an article comprising the polymer pi-bond-philic filler composite. The instant invention also generally provides a process of separating a pi-bond-philic gas from a separable gas mixture comprising the pi-bond-philic gas.

Abstract: The invention relates to a device for drying a gas, in particular air, that comprises at least one chamber (5) with an inlet (5a) for the flow of gas to be treated and an outlet (5b) for the flow of treated gas, said chamber being limited by at least one membrane (6) having a water vapor perviousness that is significantly higher than the perviousness to other gases or vapors, a humidity absorbing material being provided or flowing against the membrane (6) on the side opposite the chamber. The device includes a stack of plates (P1, P2) provided with central openings (A, B); each chamber (5) is formed by a central opening (A) located between two parallel membranes (6) while the humidity absorbing material is provided against each membrane (6); each plate (P1) is sandwiched between two plates (P2, P3) including a housing (B, B1) for the humidity absorbing material; and a plurality of chambers (5) are stacked and connected in series.

Abstract: An air dryer having an internal orifice designed into an outlet end cap that eliminates the need for external valves or regulators to control the flow of air through the dryer. The internal orifice, which can be press-fit or threaded into the end cap, provides a consistent and stable outlet flow and dew point and eliminates the need for instruments to measure outlet flow and dew point. The orifice size can be easily changed for changing outlet flow and dew point. A protective tubular shroud is provided for shielding a membrane module of the dryer, and for routing sweep gas to a bottom vent.

Abstract: Contaminating water and/or fuel material may be removed from a stream of internal combustion engine lubricating oil being circulated over parts of an operating engine. A suitable membrane material is supported in a suitable housing. At least a portion of the oil stream is flowed over one side of the membrane and water and/or fuel material diffuses through the membrane to its other side where they are gathered and removed from the housing. The water and fuel material may be recovered separately using different membranes or different regions of a membrane. They may be swept from the membranes and housings using streams of flowing air heated to a pre-selected temperatures using waste engine heat for disposition outside the housing. Application of this practice to other membrane-separable mixtures is described.

Abstract: A water vapor transfer assembly for a fuel cell system includes at least one water vapor transfer device. The water vapor transfer device permits a transfer of water from a wet stream to a dry stream. The water vapor transfer device is disposed between a pair of end plates. The end plates each have a plurality of outwardly extending ribs. The water vapor transfer device and the end plates are disposed within a housing having a pair of wet stream apertures and a pair of dry stream apertures formed therein. The housing further includes a plurality of channels formed adjacent the dry stream apertures. The channels are in fluid communication with the wet stream apertures. The outwardly extending ribs of the end plates cooperate with the channels to define a tortuous bypass flow path between the wet stream apertures of the housing.

Abstract: A method of removing water and/or methanol from fluid mixtures of the water or methanol with other compounds uses vapor permeation or pervaporation of the water or methanol, as the case may be, from the mixture through a membrane having an amorphous perfluoropolymer selectively permeable layer. The novel process can be applied in such exemplary embodiments as (a) removing water or methanol from mixtures of compounds that have relative volatility of about 1-1.1 or that form azeotropic mixtures with water or methanol, (b) the dehydration of hydrocarbon oil such as hydraulic fluid to concentrations of water less than about 50 ppm, (c) removing water and methanol byproducts of reversible chemical reactions thereby shifting equilibrium to favor high conversion of reactants to desirable products, (d) drying ethanol to less than 0.5 wt.

Abstract: The invention provides a method for the purification of a liquid by membrane distillation comprising: passing a heated vapourising stream of a liquid (retentate stream) through a retentate channel along a porous hydrophobic membrane (10), whereby vapour of the liquid flows via the pores of the membrane to the other side of said membrane, and condensing said vapour on the other side of said membrane to give a distillate stream in a distillate channel (5) which distillate is created by passing the heat of condensation (latent heat) towards a condenser surface (3), said condenser surface forming a non-porous separation between a feed stream of the liquid to be purified and said distillate stream, which feed stream is passed through a feed channel (2) in counter-current with the retentate stream, in which feed channel a space material (4) is arranged whereby at least part of the latent heat is transferred via the condenser surface to the feed stream, and whereby a positive liquid pressure difference is applied be

Abstract: Methods for the purification of steam, systems for purifying steam, methods for measuring and/or controlling steam flow rates, and uses for purified steam are provide. Also provided are substantially gas-impermeable membranes, such as perfluorinated ionomers (e.g., perfluoroethylene-sulfonic-acid/tetrafluoroethylene membranes), having a high ratio of water vapor permeation relative to gas permeation through the membrane. Also provided are methods of operation of such membranes at relatively high operating temperatures for the purification of steam and for operation of such membranes at relatively low temperature and sub-atmospheric pressures for the purification of steam. In a preferred embodiment, the system 400 for purifying steam comprises heater 404 for creating a source of a steam feed, and a purification device 416 for housing a substantially gas-impermeable membrane 424. In the operation of system 400, water, such as deionized water, is added to vessel 402 to provide a source of the steam feed.

Abstract: A membrane gas dryer includes an upstream fitting assembly, a downstream fitting assembly, a purge tube, and a sample element. The upstream fitting assembly and the downstream fitting assembly include fitting bodies and barrier sleeves. The fitting bodies and the barrier sleeves form purge plenums that are in fluid communication with the purge tube. Sealing interfaces on the fitting bodies maintain fluid-tight seals around the purge plenums as the barrier sleeves rotate about fitting bodies. The sample element includes a water-permeable membrane and passes inside the purge tube such that moisture in a sample gas flowing in a downstream direction through the sample element between the fitting body to the downstream fitting body passes moisture through the water-permeable membrane and into a purge gas flowing in the purge tube in one of an upstream direction or a downstream direction between the purge plenums.

Abstract: The instant invention generally provides polymer inorganic clay composite comprising a molecularly self-assembling material and an inorganic clay, and a process of making and an article comprising the polymer inorganic clay composite.

Abstract: A process for preparing a membrane comprising the steps of providing a composition comprising a polymerizable compound having at least 25 oxyethylene groups and at least two non-substituted vinyl groups, applying the composition to a support thereby forming a continuous layer on the support, and polymerizing the composition thereby forming a non-porous polymer film. Also claimed are the resultant membranes and their uses, e.g. for separating polar and non-polar gases.

Abstract: A water trap (1) improved with respect to handling and operational safety includes: two semipermeable membranes (2) and at least one tank (7), wherein the membranes have a water penetration pressure greater than 750 hPa and are made of the same or different PTFE laminates. The gas flow is divided in a ratio between 10:90 and 25:75 into the flush-/purge branch and analysis branch to the sensors (12) and a path parallel to the sensors (12), respectively, with the aid of the membranes and downstream filter elements and via the material and configuration.

Abstract: A liquid degasser for a space device including a gas permeable material configured for contact with a flow of liquid to be de-gassed on one side and a vacuum on the other side, and wherein the gas permeable material allows gas in the liquid to diffuse to the vacuum to remove the gas from the liquid.

Abstract: A vertically directed dryer unit (10) for compressed air, comprising a dryer cartridge (22) which, together with a housing (16, 18, 20), defines an inlet head area (92) and an outlet head area (72). A plurality of hollow membrane fibers (30) extend inside the cartridge between the two head areas, the wall material thereof being more permeable with respect to water vapor than air. An outlet valve (90) is provided between the outlet head area (72) and an outlet (74) of the drier unit. Said valve only opens when the pressure in the outlet head area (72) produces sufficient pressure for the provision of purging air. The purging air is fed to the outer surface of the membrane fibers (30) via a throttle element (70).

Abstract: The present disclosure relates to systems and methods for dehumidifying air by establishing a humidity gradient across a water selective permeable membrane in a dehumidification unit. Water vapor from relatively humid atmospheric air entering the dehumidification unit is extracted by the dehumidification unit without substantial condensation into a low pressure water vapor chamber operating at a partial pressure of water vapor lower than the partial pressure of water vapor in the relatively humid atmospheric air. For example, water vapor is extracted through a water permeable membrane of the dehumidification unit into the low pressure water vapor chamber. As such, the air exiting the dehumidification unit is less humid than the air entering the dehumidification unit. The low pressure water vapor extracted from the air is subsequently condensed and removed from the system at ambient conditions.

Abstract: The present invention relates to systems and methods for dehumidifying air by establishing a humidity gradient across a water selective permeable membrane in a dehumidification unit. Water vapor from relatively humid atmospheric air entering the dehumidification unit is extracted by the dehumidification unit without substantial condensation into a low pressure water vapor chamber operating at a partial pressure of water vapor lower than the partial pressure of water vapor in the relatively humid atmospheric air. For example, water vapor is extracted through a water permeable membrane of the dehumidification unit into the low pressure water vapor chamber. As such, the air exiting the dehumidification unit is less humid than the air entering the dehumidification unit. The low pressure water vapor extracted from the air is subsequently condensed and removed from the system at ambient conditions.

Abstract: The present disclosed embodiments relate to systems and methods for dehumidifying air by establishing a humidity gradient across a water selective permeable membrane in a dehumidification unit. Water vapor from relatively humid atmospheric air entering the dehumidification unit is extracted by the dehumidification unit without substantial membrane water vapor rejection into a low pressure water vapor chamber operating at a partial pressure of water vapor lower than the partial pressure of water vapor in the relatively humid atmospheric air. For example, water vapor is extracted through a water permeable membrane of the dehumidification unit into the low pressure water vapor chamber. As such, the air exiting the dehumidification unit is less humid than the air entering the dehumidification unit. The low pressure water vapor extracted from the air is subsequently expelled through a membrane vapor rejection unit to ambient conditions.

Abstract: The present invention relates to systems and methods for dehumidifying air by establishing humidity gradients in a plurality of dehumidification units, which are arranged in series and/or in parallel. Water vapor from air entering each stage of the plurality of dehumidification units is extracted by the dehumidification units without substantial condensation into low pressure water vapor chambers. For example, in one embodiment, the water vapor is extracted through water vapor permeable membranes of the dehumidification units into the low pressure water vapor chambers. As such, the air exiting each of the dehumidification units is less humid than the air entering the dehumidification units. The low pressure water vapor extracted from the air is subsequently compressed to a slightly higher pressure (i.e., just high enough to facilitate condensation), condensed, and removed from the system at ambient conditions.

Abstract: The present invention relates to a membrane wherein said membrane comprises a polymerized composition that comprised prior to polymerization at least one type of compound comprising at least 70 oxyethylene groups and at least two polymerizable groups. The invention further relates to the use of this membrane for separating polar gases and vapors.

Abstract: The present invention relates to a membrane wherein said membrane comprises a continuous non-porous layer comprising a polymerized composition that comprised prior to polymerization at least one type of compound having a molecular weight of at least 1500 Da and comprising at least 75 weight % of oxyethylene groups and at least two polymerizable groups each comprising a non-substituted vinyl group. The invention further relates to the use of this membrane for separating polar gases and vapors.

Abstract: A fuel source for an electrochemical cell includes two or more chemical hydride pellets, a flexible, porous, liquid water impermeable, hydrogen and water vapor permeable membrane in contact with and at least partially surrounding each hydride pellet, and a porous metal hydride layer positioned between each hydride pellet. Air gaps are between each pellet.

Abstract: A vertically directed dryer unit for compressed air, comprising a dryer cartridge which, together with a housing, defines an inlet head area and an outlet head area. A plurality of hollow membrane fibers extend inside the cartridge between the two head areas, the wall material thereof being more permeable with respect to water vapor than air. An outlet valve is provided between the outlet head area and an outlet of the drier unit. Said valve only opens when the pressure in the outlet head area produces sufficient pressure for the provision of purging air. The purging air is fed to the outer surface of the membrane fibers via a throttle element.

Abstract: An air dryer includes a housing with an air inlet, an air outlet and a liquid drain outlet; and a membrane separator having surfaces extending between a first and second ends of the membrane. A first passage in the housing is connected to the air inlet and air outlet at it respective ends and extends between the first and second ends of the membrane separator along the surfaces of the membrane separator. A second passage in the housing is connected to the drain outlet and air outlet at it respective ends and extends between the first and second ends of the membrane along a surface of the membrane separator. A valve is connected between the second passage and the drain outlet for controlling the draining of the liquid and sweep air flow through the second passage. The dryer is to be inserted in a reservoir at its inlet or outlet. A coalescing filter may be provided in the housing in series with the membrane separator and the housing would include a second drain for the coalescing filter.

Abstract: A dehydrating system is designed to maintain the availability of a plant having the dehydrating system using a water separation membrane by allowing a water separation membrane unit to be replaced while the plant is in operation. The dehydrating system comprises at least two water separation membrane units in use arranged parallel to the direction of flow of a fluid to be processed, is configured so that at least one spare water separation membrane unit can be installed parallel to the direction of flow of the fluid to be processed with respect to the at least two water separation membrane units, having monitoring devices for the product fluid to be taken out, and maintains the properties of the product fluid by operating the spare water separation membrane unit depending on the properties of the product fluid monitored by the monitoring devices.

Abstract: A passive humidifier membrane includes polyolefin with a plurality of pores, wherein the average pore size of the plurality of pores is 0.05 ?m to 0.4 ?m as established by a PMI Capillary Flow Porometer. The humidifier membrane is virtually airtight while providing a high transfer rate of water. Transfer of heat is also high. The humidifier membrane is particularly suitable for heat exchange and water transfer between fluids and, it is particularly useful for applications inside or outside fuel cells such as PEMFC. The membrane is also particularly useful in the application as humidifier for air or oxygen.

Abstract: A dehumidification type air system is configured such that a switching valve and an air-used device are connected through a dehumidifying member made of a polymer permeation membrane with moisture permeability, and by bringing a moisture emitting face of the dehumidifying member into contact with the atmosphere, supply air supplied from the switching valve through the dehumidifying member to the air-used device is dehumidified by the dehumidifying member, while the moisture permeating through the dehumidifying member is diffused from the moisture emitting face to the atmosphere through natural evaporation.

Abstract: A process for separating vapors, for example for separating water from ethanol, uses a gas separation membrane unit. Permeate from the membrane unit is compressed and may be used for example as heating steam for distillation. The membrane unit may have two or more stages. Permeate from a stage may be condensed and used for example as fermentation make up water, compressed and fed to the permeate from an upstream stage or heating steam, or fed to another membrane stage for further dewatering. The gas separation membrane unit may be used to remove water from a fermentation broth that has been partially dewatered, for example by one or more of a distillation column or molecular sieve.

Abstract: The invention is a pervaporation process and pervaporation equipment, using a series of membrane modules, and including inter-module reheating of the feed solution under treatment. The inter-module heating is achieved within the tube or vessel in which the modules are housed, thereby avoiding the need to repeatedly extract the feed solution from the membrane module train.

Abstract: In various embodiments, a support system includes a multi-layer cover sheet with a number of layers. In certain embodiments, a source to move air inside and outside the multi-layer cover sheet can be provided. The source can include a source of positive pressure or negative pressure.

Abstract: A membrane dryer includes a shell having an inner tube and an outer tube and a bundle of hollow fibers supported in the shell. A dryer air inlet into the hollow fibers and a sweep air outlet from the inner tube are at a first end of the shell. A dryer air outlet into the hollow fibers and a sweep air inlet from the inner tube are at a second end of the shell. The inner tube has a first set of circumferential openings into the sweep air space adjacent the first end of the shell and a second set of circumferential openings into the sweep air space adjacent the first end of the shell; and a second plug is in the inner tube between the first and second set of openings.

Abstract: An object of the present invention is to provide a zeolite membrane composite satisfying both the treating amount and the separation performance at a practically sufficient level, which can be applied even in the presence of an organic material and can separate/concentrate an organic material-containing gas or liquid mixture and which is economic without requiring a high energy cost and is not limited in its application range; a production method thereof; and a separation or concentration method using the same. The present invention is an inorganic porous support-zeolite membrane composite, wherein the inorganic porous support contains a ceramic sintered body and the inorganic porous support-zeolite membrane composite has, as a zeolite membrane, a CHA-type zeolite crystal layer on the inorganic porous support surface.

Abstract: There is described a composite material such as venting materials and vents containing said venting materials. The vents are air- or more generally gas-permeable venting composites that are oleophobic and liquid repellent.

Abstract: A membrane dryer includes a shell having an inner tube and an outer tube and a bundle of hollow fibers supported in the shell. A dryer air inlet into the hollow fibers and a sweep air outlet from the inner tube are at a first end of the shell. A dryer air outlet into the hollow fibers and a sweep air inlet from the inner tube are at a second end of the shell. The inner tube has a first set of circumferential openings into the sweep air space adjacent the first end of the shell and a second set of circumferential openings into the sweep air space adjacent the first end of the shell; and a second plug is in the inner tube between the first and second set of openings.

Abstract: A separator for a hydraulic system is provided, including a substrate and a membrane. The substrate includes a substrate outer surface and a gas side expulsion area. The expulsion area is for expelling gas from the separator. The membrane is in communication with the substrate, and is for permeating gas to the substrate outer surface while substantially blocking ingression of fluid to the substrate. The substrate outer surface is for receiving gas. The substrate is for transporting gas from the substrate outer surface to the expulsion area.

Abstract: Processes for dehydrating an organic/water solution by pervaporation or vapor separation using fluorinated membranes. The processes are particularly useful for treating mixtures containing light organic components, such as ethanol, isopropanol or acetic acid.

Abstract: A gas separator having excellent humidifying performance, pressure loss, volume efficiency, and durability humidifies gases used in an on-vehicle fuel cell. The gas separator has upper and lower surfaces of pleat elements of a pleat molding covered by a plate having intake and exhaust ports. The pleat molding is formed by pleating a compound membrane formed of a gas separating membrane and at least one layer of permeable reinforcement material. The pleat element is formed by disposing a reinforcement frame at the outer side part of the molding. The ratio (R=L/H) of a shortest distance (L) between the intake and exhaust ports to a height (H) of the pleat molding is 0.1 to 7.0, and the ratio (W/Le) of the width (W) to the length (Le) of the pleat molding is 0.3 to 10.0. The gas separator operates at a volume flow ratio of 200 or higher.

Abstract: A method and apparatus for humidifying air in which the first side of a permselective water transport membrane is contacted with water vapor laden flue gas from a combustion process having a first water vapor partial pressure and a first temperature and at least a portion of the water vapor is condensed, producing condensed water. The condensed water is transported through the membrane to the opposite side of the membrane, which is contacted with an air stream having a second water vapor partial pressure, which second water vapor partial pressure is less than the first water vapor partial pressure, and having a second temperature, which second temperature is less than the first temperature. Upon contact with the air stream, the condensed water evaporates into the air stream, resulting in a humidified air stream.

Abstract: A breathing air purification device and method having a carbon-monoxide free sweep stream. Water vapor is removed from a compressed air stream using a membrane dryer, comprising, a membrane having a permeate portion and a non-permeate portion, a membrane housing which encases the membrane, a membrane feed inlet conduit connected to the membrane and a non-permeate gas outlet conduit fluidly connected to the non-permeate portion of the membrane. The sweep stream used to cleanse the outer permeate portion of the membrane dryer is taken from a catalyst filter. The catalyst filter includes a cartridge containing a bed of catalyst, two end pieces maintaining the cartridge within a catalyst bed housing and having outlet holes, a catalyst inlet conduit connected to the bed of catalyst and a product gas outlet conduit connected to the outlet holes. A sweep inlet tube provides a gas connection from the catalyst filter component to the permeate portion of the membrane.

Abstract: A method and apparatus are provided for controlling the amount of purging that occurs within a membrane separation device. The membrane separation device includes a membrane separation component and sweep controlling component. Within the membrane separation component, a major portion of the non-permeate gas is sent out of the membrane separation device to work, while a minor portion is diverted for use as a sweep gas. The sweep gas is controlled by a valve that cycles with a device, such as a compressor. Thus, the membrane separation device is on when the compressor is on and is off when the compressor is off. As such, the membrane separation device is not required to sweep at all times.

Abstract: A gas-separation membrane module assembly and a gas-separation process using the assembly. The assembly includes a set of tubes, each containing gas-separation membrane elements, arranged within a housing. The housing contains tube sheets that divide the space within the housing into three separate, gas-tight spaces, with the tubes mounted in the central space. Feed gas enters the tubes through apertures positioned to feed multiple membrane elements within a tube in parallel, and one or more manifolds are used to collect residue gas from the membrane elements and direct the gas to the residue port or to a second group of membrane elements within the tube. The assembly can be used in various ways to carry out gas separation processes.

Abstract: In various embodiments, a support system includes a multi-layer cover sheet with a number of layers. In certain embodiments, a source to move air inside and outside the multi-layer cover sheet can be provided. The source can include a source of positive pressure or negative pressure.

Abstract: A lithographic projection apparatus (1) includes a support configured to support a patterning device (MA), the patterning device configured to pattern the projection beam according to a desired pattern. The apparatus has a substrate (W) table configure to hold a substrate, a projection system configured to project the patterned beam onto a target portion of the substrate. The apparatus also has a purge gas supply system (100) configured to provide a purge gas near a surface of a component of the lithographic projection apparatus. The purge gas supply system (100) includes a purge gas mixture generator (120) configured to generate a purge gas mixture which includes at least one purging gas and moisture. The purge gas mixture generator has a moisturizer (150) configured to add the moisture to the purge gas and a purge gas mixture outlet (130) connected to the purge gas mixture generator (120) configured to supply the purge gas mixture near the surface.

Abstract: Disclosed are a gas separation membrane and a gas separation method in which at least one species of organic vapor is separated and recovered from an organic vapor mixture using the gas separation membrane. The gas separation membrane is made of an aromatic polyimide composed of a tetracarboxylic acid component consisting of an aromatic ring-containing tetracarboxylic acid and a diamine component comprising 10 to 90 mol % of a combination of (B1) 3,4?-diaminodiphenyl ether and (B2) 4,4?-diaminodiphenyl ether at a B1 to B2 molar ratio, B1/B2, ranging from 10/1 to 1/10, and 10 to 90 mol % of other aromatic diamine.

Abstract: A high-temperature, steam-selective membrane for adding steam to or removing steam from various types of chemical reactions is disclosed herein. In one embodiment, such a membrane includes a polymer layer (a Nafion or sulfonated PEEK polymer layer, for example) exhibiting high selectivity to the transport of steam relative to other gas species. The polymer layer is sandwiched between substantially rigid porous layers that are steam permeable. The rigid porous layers substantially immobilize the polymer layer and reduce the tendency of the polymer layer to shrink and/or expand in response to changes in temperature or humidity. The rigid porous layers may also retain water to keep the polymer layer moist. The physical support and moisture retention provided by the rigid porous layers enable the polymer layer to operate in a temperature range of about 100° C. to 500° C.

Abstract: A method of exchanging water-water vapor between a first air stream and a second air stream includes making a third air stream, the flow velocity of which is regulated, flow through first and second intermediate volumes without cooling or heating the third air stream, dehumidifying the first air stream by making the first air stream flow through at least one first cavity which is separated by a first water-vapor-permeable structure from the first intermediate volume, and humidifying the second air stream by making the second air stream flow through at least one second cavity which is separated by a second water-vapor-permeable from the second intermediate volume.

Abstract: A purge valve for use with an air drying system is provided. The valve includes a housing or body, a piston disposed within the body, and a valve in communication with the piston. The respective geometries of the piston body and the valve define a circumferential cavity between and around the piston body and the valve. A sealing means is disposed within the circumferential cavity for forming a seal between the valve and the body. A plurality of guide members attached to or formed integrally with the valve provide positional stability to the valve within the body and provide enhanced airflow in, through, and around the valve.

Abstract: A dehydration method by which water is selectively separated from a water-containing mixture 31 with a separation membrane. The separation membrane is a DDR type zeolite membrane 2. The dehydration method includes bringing the mixture 31 into contact with one side of the DDR type zeolite membrane 2 and causing a pressure difference between that side of the DDR type zeolite membrane 2 which is in contact with the mixture and the other side of the DDR type zeolite membrane 2 to thereby cause the water to selectively permeate and separate out. By the dehydration method, water can be selectively separated from a water-containing mixture without the need of a high energy cost. The separation membrane has excellent acid resistance.