Abstract: A breathable, stretch-thinned barrier film having improved strength, processability and/or breathability is formed from a mixture of a thermoplastic polymer and cavated filler particles such as cyclodextrin. The cavated filler particles provide the film with enhanced breathability to water vapor due to their ring-like, conical, cylindrical or otherwise hollow molecular structure, yet the film remains substantially impermeable to aqueous liquids. The enhanced breathability occasioned by the cavated particles permits the use of relatively low filler levels and correspondingly high polymer levels, thereby enhancing the film strength. The filler may melt during extrusion of the molten polymer into a film, facilitating smooth processing, and re-crystallize into particles after the film is formed and cooled.

Abstract: A process for treating natural gas or other methane-rich gas to remove excess nitrogen and carbon dioxide simultaneously. The invention relies on membrane separation using nitrogen/methane and carbon dioxide/methane selective membranes. The gas can typically be brought to pipeline specification for both components, without requiring the use of amine scrubbing or other acid gas removal technique. Where water vapor or hydrogen sulfide is present in the raw gas, these contaminants may also be removed to meet pipeline specification in a single operation.

Abstract: A hollow fiber membrane dehumidification device that possess hollow fiber membranes that cause the compressed air supplied from one end to the interior to flow through and at the same time discharge moisture in the compressed air to the outside, and by so doing exhausts the compressed air to the other end as dehumidified air. There is a reflux route that causes a portion of the dehumidified air exhausted from the hollow fiber membranes to flow back to the outside of the hollow fiber membranes as purged air and a variable restrictor that is provided on the reflux route that increases or decreases the opening-closing volume in accordance with the increase or the decrease of the pressure of the compressed air that flows through the interior of the hollow membranes.

Abstract: A hollow fiber membrane dehumidification device with a housing chamber open to atmosphere via a through hole. Hollow fiber membranes are disposed in the housing chamber and cause compressed air entering from one end to flow through and be discharged at the other end as dehumidified air by discharging moisture to the outside housing chamber. A reflux route is provided to permit a portion of the dehumidified air to flow back to the housing chamber as purged air. First and second orifices are provided on the reflux route wherein the second orifice has an opening diameter larger than that of the first orifice.

Abstract: A method for removing a condensable component from a process stream in which a first side of a permselective membrane is contacted with the process stream in which is disposed the condensable component. The condensable component is passed through the permselective membrane to a second side of the permselective membrane, forming a condensable permeate. The condensable permeate is then contacted with a liquid stream having a liquid form of the condensable permeate, forming a condensed permeate. The condensed permeate may then be returned to the process which generated the process stream.

Abstract: An integral hollow fiber membrane gas purification apparatus is disclosed. The apparatus comprises one or more filtration elements and a hollow fiber membrane cartridge placed coaxially in a common housing. In some embodiments, the filtration elements are omitted and the hollow fiber membrane cartridge is employed as a combined gas separation/filtration device. The apparatus of this invention is particularly useful for conditioning compressed air that includes the removal of both suspended matter and water vapor.

Abstract: A humid gas stream is dehumidified by bringing that stream into contact with the front surface of a hydrophilic capillary condenser layer that captures the water and moves it adjacent the rear surface of the capillary layer. A semi-permeable collodion membrane, is disposed on the rear capillary surface of the condenser layer, and an osmotic fluid, such as glycerol, is disposed adjacent the collodion membrane. An osmotic driving force, resulting from a water concentration gradient across the collodion membrane, transports the condensed water from the condensing layer through the thickness of the membrane and into an osmotic fluid. The collodion membrane also inhibits the osmotic fluid from flowing into the condenser layer.

Abstract: A method for removing a condensable component from a process stream in which a first side of a permselective membrane is contacted with the process stream in which is disposed the condensable component. The condensable component is passed through the permselective membrane to a second side of the permselective membrane, forming a condensable permeate. The condensable permeate is then contacted with a liquid stream having a liquid form of the condensable permeate, forming a condensed permeate. The condensed permeate may then be returned to the process which generated the process stream.

Abstract: In an arrangement for removing water vapor from pressurized gases or gas mixtures, particularly from air, a membrane separating apparatus is provided wherein the gas-vapor stream is separated into a vapor-enriched permeate stream and a vapor-depleted retentate stream and the vapor enriched permeate stream is conducted to a vacuum pumping device for generating at the permeate side of the membrane separating apparatus a vacuum providing for a predetermined trans-membrane pressure ratio.

Abstract: A hollow fiber membrane gas separation apparatus of a compact design suitable for separation and purification of gases is disclosed. The apparatus comprises an outer housing that consists of a detachable bowl and a head closure, and a removable hollow fiber membrane cartridge positioned therein. The cartridge contains a concentric tubular inner core member and is surrounded by a shell and at least one end closure. The cartridge is attached by its first axial end in a sealed and removable manner to a gas flow conduit positioned coaxially in the housing closure wherein said conduit being in fluid communication with a gas inlet or product gas outlet port formed in the housing head closure and by its second axial end to a waste gas exit port in the bowl.

Abstract: An asymmetric membrane is formed using a mixture of two or more different polymers including at least one type of polyimide. It is thereby possible to produce a gas separation membrane with low permeation resistance (a high permeation rate) for permeate gases passing through the porous layer of the membrane, which also maintains a practical level of mechanical strength of the membrane and has excellent water resistance and hot water resistance.

Abstract: A humid gas stream is dehumidified by bringing that stream into contact with the front surface of a hydrophilic capillary condenser layer that captures the water and moves it adjacent the rear surface of the capillary layer. A semi-permeable collodion membrane, is disposed on the rear capillary surface of the condenser layer, and an osmotic fluid, such as glycerol, is disposed adjacent the collodion membrane. An osmotic driving force, resulting from a water concentration gradient across the collodion membrane, transports the condensed water from the condensing layer through the thickness of the membrane and into an osmotic fluid. The collodion membrane also inhibits the osmotic fluid from flowing into the condenser layer.

Abstract: A downhole preferential hydrocarbon gas recovery system and method employ preferentially selective materials to separate the hydrocarbon gas from contaminants. According to one aspect of the invention, the preferentially selective materials are arranged in tubes with the hydrocarbon gas flowing through the tubes and the contaminants permeating out through the preferentially selective material.

Abstract: A method for purifying a minority constituent and concentrating it in a majority constituent of a gas mixture that also contains one or more other minority constituent(s) employs (i) a selective permeation step, (ii) next, a purification step, and (iii) finally a concentration step. In the selective permeation step, an initial gas mixture is passed through a membrane to yield a gas mixture that is enriched in the first minority constituent. In the purifying step, the first minority constituent is absorbed by a solid adsorbent which has a strong affinity for the first minority constituent, then following an elution step, a gas mixture that contains essentially only the majority constituent and the first minority constituent is formed.

Abstract: The invention is concerned with a device and a process for drying air in ventilation devices for fuel tanks and gas drying in fuel tanks via vapor permeable membranes and sorbents.

Abstract: A gas separator, a method for producing the gas separator, and a method for separating gases based on a property of inelasticity of the gases. The inventive gas separator is a permeable porous material for separating a mixture of gases by selectable pore size exclusion, comprising pores formed with at least one nanostructured compound. In other words, the inventive porous material can be used to separate a mixture of gases based upon the different working diameter of each of the gases. By selecting specific nanostructured compounds, the porous material can be tailored to contain pores of a predetermined size which allow gases having a working diameter smaller than the size of the pores to pass through the material while preventing the passage of gases having a working diameter greater than the size of the pores.

Abstract: Water- and ion-conducting membranes composed of sulfonated statistical arylvinyl polymers, the arylvinyl polymer comprising at least one arylvinyl monomer and at least one olefin monomer and wherein aromatic moieties derived from the arylvinyl monomer are at least partially sulfonated, are used as proton-conducting membranes for production of electricity, as water-conducting membranes for humidification of fuel gases in fuel cells and heat and moisture exchange in heating/ventilation/air conditioning systems. Water-conducting membranes composed of sulfonated arylvinyl polymers, the arylvinyl polymer comprising at least one arylvinyl monomer and wherein aromatic moieties derived from the arylvinyl monomer are at least partially sulfonated are used for desalination of seawater.

Abstract: Porous titanium silicate molecular sieves are produced in the form of a membrane capable of separating fluid molecular mixtures.

Abstract: Potassium or other alkali metal formate solution is used to absorb moisture from gas through a membrane. The membrane may be supported on permeable tubes, and the potassium or other alkali metal formate may be regenerated for reuse, preferably by a cavitation regenerator. The potassium or other alkali metal formate should be present as a 40-80% solution, most preferably 70-76%. The process is especially useful for the dehydration of natural gas.

Abstract: The invention relates to a method of making an epoxysilicone coated membrane by coating a porous asymmetric membrane layer with a UV-curable controlled release epoxysilicone coating. A mixture of the epoxysilicone resin and an onium photocatalyst are applied to the porous asymmetric membrane layer in a dilute non-polar solution and cured by UV or electron beam radiation to produce a dry epoxysilicone coated membrane. The porous asymmetric membrane layer is comprised of an asymmetric cellulosic membrane or an asymmetric polymer membrane with a low selectivity. The epoxysilicone coating was found to provide the asymmetric membrane layer with improved selectivity which extends to separation temperatures below 70° C. and provides stable flux rates. Membranes produced in this manner are useful for the separation of gases such as carbon dioxide from natural gas.

Abstract: An asymmetric membrane is formed using a mixture of two or more different polymers including at least one type of polyimide. It is thereby possible to produce a gas separation membrane with low permeation resistance (a high permeation rate) for permeate gases passing through the porous layer of the membrane, which also maintains a practical level of mechanical strength of the membrane and has excellent water resistance and hot water resistance.

Abstract: The invention relates to an apparatus for performing membrane gas/liquid absorption at elevated pressure, comprising a pressure vessel in which a membrane unit is provided for separate feed-through of the gas phase and the liquid phase, in such a way that exchange of components to be absorbed can take place between the gas phase and the liquid phase, the flow direction of the gas phase through the absorber being essentially perpendicular to the flow direction of the liquid phase through the absorber. The invention further relates to a method for performing gas/liquid membrane absorption employing this absorber, in particular for the absorption of CO2, H2S, mercury (vapor) and/or water (vapor) from a gas phase at elevated pressure. The invention finally relates to a method for refining natural gas using the absorber and method according to the invention.

Abstract: Aqueous streams containing organic and/or inorganic contaminants are purified by the removal of the contaminant by contacting the aqueous stream with a membrane formed from a porous, crystalline titanium silicate.

Abstract: The dryer for compressed air comprises a filter bowl (20), which has an inlet (22) for damp compressed air, an outlet (24) for dried compressed air, a scavenging air inlet (26) and a scavenging air outlet (28). A membrane is accommodated in the filter bowl (20). The membrane lets selectively water steam flow through and has two sides. One side of the membrane is stroked by the compressed air, while scavenging air flows on the other side of the membrane. A feeder pipe (32) is provided, through which dried compressed air coming from the outlet (24) is fed into the scavenging air inlet (26). A closing device (34, 36, 38) is arranged in the feeder pipe (32) and has a closed position. The closed position depends on the consumption of compressed air in such a way that more or less scavenging air is made available when more or less compressed air is taken by a consumer device, operated by dried compressed air.

Abstract: The present invention provides a means and a device to control relative humidity and airborne contaminants within a defined environment. The devices and methods of the present invention enable a user to regulate the relative humidity of a defined environment and insure that extreme conditions, e.g. less than 15% or greater than 90% relative humidity, do not exist. The air quality control system can also be used to control the relative humidity in and about a narrow range. Control over relative humidity and airborne contaminants is achieved by combining an appropriate salt and water solution, such as a saturated salt solution with a solid phase of that salt, with an isolation membrane and a getter system. The present invention is particularly useful for housing sensors, such as SIR sensors, which are sensitive to relative humidity extremes.

Abstract: A mixed gas-separating membrane module having a high separating efficiency includes a cylindrical container having a mixed gas-feed section, a non-permeated gas-delivery section, and a middle section; a bundle of a plurality of hollow fibers each extending through the middle section and each having an end portion opening to the mixed gas-feed section and an opposite end portion opening to the non-permeated gas-delivery section; a pair of a first disk supporting the hollow fiber end portion opening to the mixed gas-feed section and partitioning the middle section from the mixed gas-feed section, and a second disk supporting the opposite hollow fiber end portions opening to the non-permeated gas-delivery section and partitioning the middle section from the non-permeated gas-delivery section, the first and second disks supporting the hollow fibers so that the hollow fibers are spaced from each other, to leave a continuous space between the hollow fibers; and a cylindrical film member surrounding the hollow fiber

Abstract: The invention relates to a process for providing subjects with an increased oxygen supply. Prior art processes, especially diaphragm or molecular sieve technology, are used to prepare oxygen-enriched pure air (10), which is used to flood premises in a building, an “oxygenarium”. These premises are large enough for the subjects exposed to this atmosphere to have considerable freedom of movement, while at the same time it is possible for them to perform strengthening or rehabilitation exercises. The air consumed by the subjects is reprocessed and fed back into the oxygenarium with fresh outside air.

Abstract: An improved plate-and-frame assembly selectively transfers a fluid component from one fluid stream to another fluid stream. In a preferred embodiment, a plate-and-frame humidity exchanger with unitary plates and seals transfers water vapor and heat between two fluid streams.

Abstract: A small system for efficiently producing low flow rates of a nitrogen or nitrogen/hydrogen stream from an initial feed which also contains oxygen, employing a defined catalytic reactor unit producing product at very high space velocities.

Abstract: A combination gas drying and reservoir apparatus includes a reservoir, a membrane dryer disposed inside the reservoir and a control scheme that reduces the amount of gas lost as sweep gas from the dryer. The reservoir has an inlet flange that receives moisture laden gas from a compressor, an outlet flange from which dried gas discharges to a pneumatic system and a purge flange. The dryer includes a vessel encasing a membrane unit between its inlet and outlet ends. A purge port of the vessel communicates with the purge flange to form a purge channel. The inlet end of the vessel is connected to the inlet flange from which it receives the moisture laden gas. The moisture laden gas then flows into the membrane unit. Sweep gas that has permeated through membranes flows from a sweep space defined between the vessel and the membrane unit to the purge channel. Dried gas flows out of the membrane unit through the outlet end of the vessel into the reservoir.

Abstract: An apparatus for utilizing semi-permeable membrane technology to process compressed air in such applications as a compressed air system of a railway locomotive.

Abstract: A process for recovering SF.sub.6 from a gas is provided. The process includes the step of contacting a gas stream comprising SF.sub.6 and at least one of N.sub.2, O.sub.2, CO.sub.2, and H.sub.2 O with a membrane in at least one membrane separation unit at conditions effective to obtain a retentate stream rich in SF.sub.6 and a permeate stream rich in at least one of N.sub.2, O.sub.2, CO.sub.2, and H.sub.2 O. A process for forming solidified Mg metal is also provided. The process includes recovering and/or recycling of SF.sub.6 and/or CO.sub.2.

Abstract: A bi-directional air exchanger for a metal-air battery having a housing. The air exchanger includes an ambient air passageway for a first flow of air in a first direction, a battery exhaust passageway for a second flow of air in a second direction, and one or more membranes. The ambient air passageway and the battery exhaust passageway are separated within the housing by the one or more membranes such that the first and the second flows of air are in fluid communication with one another for the exchange of humidity.

Abstract: The invention relates to a gas dehydration membrane comprising a membrane having pores communicating between a first and an opposing second surface of the membrane and further having an average pore diameter on the first surface of the membrane which is about 10 to 1000 times smaller than that on the opposing second surface of the membrane. The invention further relates to a process for dehydrating a gaseous feedstock comprising passing the gaseous feedstock over a membrane characterized by high surface porosity wherein pore openings on a first surface thereof are at least 10 to 1000 times smaller than pore openings on an opposing surface thereof and wherein from about 2% to about 30% of the pore volume is occupied by a humectant.

Abstract: A control system reduces the amount of gas lost as sweep gas from a membrane gas dryer. The membrane gas dryer is of the type that features an inlet end that receives moisture laden gas from a compressor, an outlet end from which dried gas is discharged to a pneumatic component and a drain port from which permeate sweep gas inclusive of permeate water vapor is expelled from the gas dryer. The control system includes a purge valve that is connected to the drain port of the gas dryer and a mechanism that controls the purge valve. The purge valve has a pilot port that responds to pressure by closing the purge valve thereby preventing the permeate sweep gas from exhausting to atmosphere through the drain port.

Abstract: A method of separating iodine gas by passing a phase containing iodine gas through a hydrophobic separation membrane containing pores having a pore diameter of 1 nm to 60 .mu.m, retaining iodine gas on the upstream side of the flow of the phase in the separation membrane, and removing the phase from which iodine gas has been removed from the downstream side of the separation membrane. In addition, a membrane that is impermeable to water but permeable to steam is used in combination with this separation membrane.

Abstract: A system for the ultrapurification of organic solvents comprising (1) a membrane-based vapor permeation step for selective removal of water vapor from the solvent, wherein a countercurrent sweep stream is used that has a particular partial pressure of water vapor, (2) a filtration step for selective removal of particulates, and (3) an ion exchange step for selective removal of ionic species.

Abstract: This invention relates to a miniaturizable separation module (dehumidifier, humidifier) utilizing the gas separation property of waterproof membranes having fine moisture-permeable through holes. The separation module according to the invention comprises: a cylindrical casing 10 installed at the wall of a moisture-proof and drip-proof box 4, so as to form a gas passage communicating the inside and the outside of the box; a plurality of waterproof membranes 1, 2, 3, having fine moisture-permeable through holes, disposed in the cylindrical casing at intervals of spacing, so as to form chambers 5, 6 in the gas passage; and conductive porous structures disposed in proximity of the waterproof membranes. The longitudinal section of the solid portion around the holes of the conductive porous structure is formed into an essentially egg-like shape, and the acute angle side of the egg-like longitudinal sectional shape is disposed so as to direct to the waterproof membrane.

Abstract: A process for conditioning natural gas containing C.sub.3+ hydrocarbons and/or acid gas, so that it can be used as combustion fuel to run gas-powered equipment, including compressors, in the gas field or the gas processing plant. Compared with prior art processes, the invention creates lesser quantities of low-pressure gas per unit volume of fuel gas produced. Optionally, the process can also produce an NGL product.

Abstract: A mass transfer composite membrane for use with a fuel cell power plant includes a transfer medium core between opposed, rigid, porous support sheets. An inlet surface of the composite membrane is positioned in contact with an oxidant inlet stream of a fuel cell power plant, and an opposed exhaust surface of the composite membrane is positioned in contact with an exhaust stream exiting the fuel cell power plant to recover mass such as water from the exhaust stream and transfer it into the oxidant inlet stream entering the fuel cell. The transfer medium core may comprise any of a variety of materials for sorbing a fluid substance consisting of polar molecules such as water molecules from a fluid stream consisting of polar and non-polar molecules. A preferred transfer medium core is an ionomeric membrane such as a water saturated polyfluorosulfonic acid ionomer membrane.

Abstract: A gas sampling apparatus includes a probe tube having a tip positionable in a stream of products of combustion and a sample dryer tube connected in fluid communication with an end of the probe tube opposite the tip. The sample dryer tube is received in a purge gas tube along a lengthwise axis thereof. The purge gas tube and the sample dryer tube define therebetween a space through which a purge gas pump urges a purge gas in a first direction. A sample pump connected in fluid communication with the sample dryer tube urges therethrough in a second direction opposite the first direction a sample of gas obtained from the stream of products of combustion via the probe tube. A sensor is positioned to detect a constituent of the sample of gas exhausted from the sample dryer tube. The sample dryer tube is formed at least in part of a hydrophilic membrane and the purge gas entering the space contains less water vapor than the sample of gas.

Abstract: The present invention relates to an improved method and apparatus for separating one or more condensable compounds from a mixture of two or more gases of differing volatilities by capillary fractionation in a membrane-type apparatus, and a method of forming porous structures therefor. More particularly, the invention includes methods of forming and using an apparatus consisting, at least in part, of a porous structure having capillary-type passages extending between a plurality of small openings on the first side and larger openings on a second side of the structure, the passages being adapted to permit a condensed liquid to flow therethrough substantially by capillary forces, whereby vapors from the mixture are condensed, at least in part, and substantially in and adjacent to the openings on the first side, and are caused to flow in a condensed liquid state, substantially in the absence of vapor, from the openings on the first side to the openings on the second side.

Abstract: A condenser system for controlling vapor concentration contained in a flowing airstream is provided. The flowing airstream has an initial temperature upon entering the condenser system and a final temperature upon exiting the condenser system. The condenser system has a membrane member allowing mass transfer of the vapor therethrough with the airstream contacting the membrane member. A condensing member diffuses the vapor from the airstream through the membrane member. An insulating layer is positioned between the membrane member and the condensing member with the insulating layer inhibiting heat transfer between the flowing airstream and the condensing member wherein the final temperature of the airstream is substantially equal to the initial temperature of the airstream.

Abstract: A compressed air drying apparatus employs a hollow fiber membrane dryer to provide a compressed air stream having a low dew point for outdoor use. Energy efficiency is obtained by purging water vapor from the hollow fiber membrane dryer with an adsorption-dried atmospheric air flow and by using a portion of the atmospheric air flow to regenerate the adsorption drying medium, preferably with heat from the compressor.

Abstract: A system for controlling the atmosphere in the container comprising a membrane separation apparatus to separate nitrogen and a second separation apparatus, adapted to separate carbon dioxide and water vapor from a gas mixture in the container. The separated nitrogen is returned to the container, as is at least a portion of the carbon dioxide and water vapor, so as to produce and/or maintain a pre-determined atmosphere composition within the container thereby to prevent spoilage of perishable products within the container.

Abstract: A carbonaceous adsorbent membrane is prepared by contacting a hydrophobic carbonaceous adsorbent membrane with an aqueous solution of one or more oxidizing acids and one or more metals selected from the group consisting of copper (+2), chromium (+3), and nickel (+2). The treated membrane is rinsed and dried to yield a hydrophilic carbonaceous adsorbent membrane which is useful for removing water from water-containing gas mixtures.

Abstract: A membrane dryer apparatus for moist air includes a housing (1) that contains a tubular fabric strand bundle (7) of tubular fabric strands (8) made of selective absorption material through which air to be dried flows, water vapor diffusing through the fabric and collecting on its outside. A portion of the dried compressed output air is channeled off near the discharge (12) of the membrane dryer and passed through a scavenging air duct (14) having a throttle (16) and passed around the outside of the fabric strand bundle to scavenge moisture and remove it through discharge openings (17, 18) to the outside air. To limit consumption of scavenging air, an independent shut-off valve (19), working as an airflow sensor, is installed in the output air duct (13), and this shut-off valve (19) opens only when output air is actually extracted by a user.

Abstract: A process train for treating a gas stream containing methane, nitrogen, and at least one of water vapor, acid gas, C.sub.3+ hydrocarbons and aromatic hydrocarbons, the gas stream typically, but not necessarily, being natural gas. The treatment train includes separation of methane from nitrogen by means of membranes that preferentially permeate methane and reject nitrogen. Preferred processes include both a dehydration step and an NGL removal step to treat the gas before it passes to the methane/nitrogen membrane separation step. The process train can also include additional steps, such as an acid gas removal step, or a cryogenic methane/nitrogen separation step.

Abstract: An uncontrollable dehydrator where the uncontrollable discharge is augmented with a purge gas to increase the capacity of the dehydrator to achieve a target flow rate and dew point.

Abstract: An apparatus and method for separating oxides of heavy isotopes of hydrogen (deuterium oxide and oxides of tritium oxide) from water which is contaminated with these heavy hydrogen isotopes such as that currently being discharged from nuclear power plants. A central aspect of this invention includes an elongated length of hollow core fiber (HCF). By pumping the contaminated water into the HCF on either a static or a dynamic flowing basis, significant amounts of the oxides of heavy hydrogen isotopes remain in the HCF for subsequent disposal, the water discharging from the exit end thereof being substantially lower in heavy hydrogen isotope content.