Micropores Patents (Class 159/DIG27)
  • Patent number: 5976324
    Abstract: A process as been found for the removal of water from reaction mixtures of acids or acid anhydrides or of aqueous alkali metal hydroxide solutions with alcohols using vapor permeation/pervaporation at the boiling point of the reaction mixture, which includes initially introducing the lowest-boiling educt in less than the stoichiometric amount, based on the other particular educt, together with this other educt, heating the reaction mixture to the boiling point and freeing the vapor mixture, which is formed from the boiling reaction mixture and includes chiefly water and the lowest-boiling component, from water on a membrane, recycling the vapor mixture which has been freed from water into the reaction mixture and topping up the reaction mixture with the lowest-boiling educt in the course of the reaction.
    Type: Grant
    Filed: October 7, 1997
    Date of Patent: November 2, 1999
    Assignee: Bayer Aktiengesellschaft
    Inventors: Andreas Groschl, Adolf Winkler, Josef Bremen
  • Patent number: 5868906
    Abstract: A method for the on-site reprocessing of isopropyl alcohol used in semiconductor manufacturing, to generate an ultradry and ultrapure isopropyl alcohol. This ultradry and ultrapure isopropyl alcohol is produced through a pervaporation step, followed by double distillation. In the first distillation step, an autonomous azeotropic self-stripping distillation column is used to produce an ultradry and partially purified isopropyl alcohol. In the next step, the isopropyl alcohol is distilled in an overhead product distillation column, to produce an ultrapure and ultradry isopropyl alcohol. Alternatively, if the feed isopropyl alcohol contains less than 2000 ppm water, the pervaporation step may be omitted.The resulting isopropyl alcohol has between a high of 100 parts per million (ppm) and a low of 0.1 ppm of water in the isopropyl alcohol. It also has zero particles per milliliter of a size larger than 2.0 microns, zero to 2 particles per milliliter of a size of 0.5 micron to 2.
    Type: Grant
    Filed: August 2, 1996
    Date of Patent: February 9, 1999
    Assignee: Athens Corporation
    Inventors: John A. Adams, Gerald A. Krulik, Christopher Blatt, David Persichini
  • Patent number: 5681433
    Abstract: A process for the dehydration of a vaporous mixture. The basic process involves directing a predominantly condensable water vapor-containing vaporous mixture against the feed side of a membrane while maintaining the feed near saturation without condensing it, directing a condensable vapor sweep stream past the permeate side of the membrane in a countercurrent flow, thereby transporting water vapor in the vaporous mixture from the feed side to the permeate side of the membrane to form a noncondensed combined permeate side mixture of condensable vapor and transported water vapor.
    Type: Grant
    Filed: September 14, 1994
    Date of Patent: October 28, 1997
    Assignee: Bend Research, Inc.
    Inventors: Dwayne T. Friesen, David D. Newbold, Scott B. McCray, Roderick J. Ray
  • Patent number: 5628901
    Abstract: A single vessel with no moving parts is constructed to perform the functions of coalescing, vacuum dehydration, and thin film evaporation.
    Type: Grant
    Filed: April 30, 1993
    Date of Patent: May 13, 1997
    Assignee: Castrol Industrial North America Inc.
    Inventors: William L. Lawrence, Robert D. Coyle
  • Patent number: 5552023
    Abstract: Recovery of ethylene glycol from dilute aqueous solutions is accomplished by passing the solution over the surface of a porous hydrophobic membrane capable of passing water vapor but not liquid water. The pressure and temperature provide a positive driving force for the movement of water vapor through the membrane to the opposite face where it is removed by condensation or a stream of gas or liquid. Preliminary concentration of the aqueous solutions may be provided by use of reverse osmosis membrane. The method is useful in the reclamation of spent deicing fluid.
    Type: Grant
    Filed: December 15, 1993
    Date of Patent: September 3, 1996
    Assignee: AlliedSignal Inc.
    Inventor: Shaojun J. Zhou
  • Patent number: 5522970
    Abstract: Distilling tube apparatus for converting salt water such as sea water into fresh water is provided. The apparatus includes a first tube through which a feed stream of heated salt water is caused to flow, the first tube being constructed of a porous material which is both water-vapor permeable and liquid water impermeable, which tube allows water vapor to permeate through its walls thereof when heated salt water flows therethrough, the vapor then condensing outside of the first tube upon cooling of the vapor thereat. This first tube is preferably constructed of porous, expanded polytetrafluoroethylene. A second tube oriented in generally parallel relationship and in close proximity to the first tube is provided through which cooling water is caused to flow. The cooling water is maintained at a temperature lower than that of the heated salt water, thereby resulting in a lowering of the temperature of the surroundings of the second tube and providing an enhanced driving force for distillation of the salt water.
    Type: Grant
    Filed: December 2, 1994
    Date of Patent: June 4, 1996
    Assignee: Japan Gore-Tex, Inc.
    Inventors: Yutaka Shimizu, Yoshiyuki Otsuka, Yoshihiko Hiraga, Atsushi Tanigawa, Masayuki Kobayashi
  • Patent number: 5494556
    Abstract: A method of separating a liquid mixture wherein the liquid mixture is heated; the heated liquid mixture is supplied to a pervaporation membrane module to separate a permeable component of the liquid; a portion of non-permeated liquid is circulated through a circulation pipe into a liquid mixture feeding pipe before a heater, and the remaining portion of the non-permeated liquid is extracted to the outside of the system, and wherein the temperature of the liquid in the liquid mixture feeding pipe in which the non-permeated liquid has been mixed with the liquid mixture or in the circulation pipe for the non-permeated liquid, is measured, and when the measured temperature is out of a predetermined range, new supply of the liquid mixture and/or extraction of the non-permeated liquid is stopped.
    Type: Grant
    Filed: November 28, 1994
    Date of Patent: February 27, 1996
    Assignees: Mitsubishi Chemical Corporation, Mitsubishi Kasei Engineering Company
    Inventors: Masaaki Mita, Masumi Hino, Moriyoshi Kudo
  • Patent number: 5445731
    Abstract: Apparatus for breaking or separating a liquid mixture or emulsion having two or more components. The apparatus includes a closed vessel having one or more sequentially connected filtering compartments holding a filtering element such as a membrane assembly capable of achieving a multi-stage pervaporation to separate out a vaporous component of the solution. The apparatus further includes a bypass facility which interconnects adjacent filtering compartments. To compensate for the loss of heat energy during the vaporization segments, the residual liquid solution is bypassed into a second vaporization phase, the bypass facility including heating means for maintaining the residual solution of a predetermined liquid temperature prior to its entering the second or subsequent filtering phase.
    Type: Grant
    Filed: September 8, 1993
    Date of Patent: August 29, 1995
    Assignee: Texaco Inc.
    Inventors: David Tuohey, Craig R. Bartels, Vatsal M. Shah
  • Patent number: 5385647
    Abstract: A process for reducing the alcohol content of alcohol-containing beverages, in particular of beer or wine, wherein the alcohol is partially or completely removed by way of pervaporation.
    Type: Grant
    Filed: January 21, 1993
    Date of Patent: January 31, 1995
    Assignee: Deutsche Carbone AG
    Inventors: Hartmut E. A. Brueschke, Walter H. Schneider, Guenter F. Tusel
  • Patent number: 5304287
    Abstract: A microdistillation method for the quantitative steam distillation of cyanide, phenolic compounds, hydrogen fluoride, ammonia, sulfites and other volatile analyte compounds from samples of environmental waters and sludge for their subsequent analysis involves volatilizing the water in the sample tube of a microdistillation column. The pressure which develops due to the water vapor forces all volatile compounds from the water sample, including the water itself, through a hydrophobic membrane and into the collector tube of the microdistillation column. The volatile compounds and the water vapor condense in the cooler collector tube and are quantitatively trapped and retained over the membrane. Relatively small samples may be distilled.
    Type: Grant
    Filed: February 7, 1991
    Date of Patent: April 19, 1994
    Assignee: Lachat Instruments
    Inventor: Scott Stieg
  • Patent number: 5300197
    Abstract: A distillation apparatus includes a distillation unit for distilling feed water. The distillation unit includes an evaporation part, a condensation part and a hydrophobic porous membrane interposed between the evaporation part and the condensation part, which are integrated with one another. A heating unit for heating the feed water and a cooling portion for cooling distillate produced by distillation of the feed water are provided apart from the distillation unit. One or both of the heating unit and the cooling unit are provided with a heat pump. With this construction, an additional heater does not need to be provided, and the distillation unit and both of the heating unit and the cooling unit can be changed in size and performance independently of each other, so that the overall size of the distillation apparatus can be reduced.
    Type: Grant
    Filed: December 10, 1990
    Date of Patent: April 5, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Kenji Mitani, Akira Ashida, Katsuya Ebara, Hideaki Kurokawa
  • Patent number: 5290403
    Abstract: A liquid evaporating apparatus includes a liquid inlet 1 to which an evaporator 2 is connected which incorporates a gas inlet 28 and gas flow channels defined by vapor-permeable hydrophobic walls 23, 24, 25, 26. The apparatus may be used to moisturize air in a room, in which case it is configured to circulate room air through the evaporator and to discharge vaporized liquid through the output side 22 of the evaporator and into the room. Alternatively, the apparatus may be used to cleanse liquid, in which case it includes a condensing chamber 3 connected to the output side of the evaporator. The apparatus will also include a closed gas loop 4 which is located between the output side and the input side 21 of the evaporator and which incorporates a fan 5 for transporting a vapor-gas mixture continuously to the condensing chamber.
    Type: Grant
    Filed: May 27, 1993
    Date of Patent: March 1, 1994
    Inventor: Aapo Saask
  • Patent number: 5268150
    Abstract: A concentrator/extractor apparatus for employing solvent to extract a substance from a sample in order to increase the concentration of the substance in less time than prior art apparatuses is disclosed. The disclosed apparatus, and kits including the disclosed apparatus and compatabile components, is provided with a sample containing body in which a hydrophobic membrane is utilized to prevent the sample liquid from migrating to the concentrator portion of the combination extractor/concentrator apparatus. Solvents having densities greater than, or lower than, the sample may be used to process such samples by the disclosed apparatus.
    Type: Grant
    Filed: December 18, 1991
    Date of Patent: December 7, 1993
    Assignee: Corning Incorporated
    Inventor: David T. Burkitt
  • Patent number: 5246549
    Abstract: An apparatus for distilling corrosive compounds under high temperatures, which would include primary vessel chamber, having a first interior annular wall lined with a loose polymer, such as PTFE (or TEFLON), a second annular wall exterior to the first annular wall, and defining an annular space between the interior and the exterior wall; a somewhat rigid porous material for supporting the interior PTFE liner positioned along the interior wall of the vessel; device for drawing air out of the annular space between interior and exterior walls, for creating a vacuum at the annular space, so that the PTFE liner is supported firmly against the somewhat rigid porous support member; next, a second means for drawing air out of the interior of the vessel for creating a vacuum therewithin so that a pressure equilibrium is established between the interior of the vessel and the annular space, and a corrosive material can be heated in the vessel chamber under the vacuum, and the liner be maintained flush against the wall o
    Type: Grant
    Filed: August 26, 1991
    Date of Patent: September 21, 1993
    Inventor: John Heil
  • Patent number: 5232085
    Abstract: A distillation system has a degassing tank, a distiller for generating vapor of raw water taken from the degassing tank, a heater for heating the vapor from the distiller to convert the vapor into a high temperature and pressure vapor, a hydrophobic porous membrane through which the vapor from the heater flows, and a heat transfer unit provided in the distiller for effecting heat exchange between the vapor from the membrane member and the raw water from the degassing tank. The structural elements such as the heat exchange unit, piping, etc., with which the vapor from the membrane or the condensate thereof is brought into contact are made of titanium or titanium alloy.
    Type: Grant
    Filed: July 25, 1991
    Date of Patent: August 3, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Nobuatsu Hayashi, Susumu Horiuchi, Hiroaki Yoda
  • Patent number: 5203969
    Abstract: A method of separating and recovering components of a mixture having a gap in the range of miscibility and having organic compounds and water in a pervaporization process with the aid of membranes. The mixture is first separated into an organically loaded water phase and a water-saturated organic phase. Subsequently, the organically loaded water phase and the water-saturated organic phase are separately subjected to parallel, different pervaporization processes, resulting in retentates as water on the one hand and organic liquid on the other hand. The permeates that result during the pervaporization processes are subsequently returned to the mixture that is to be separated.
    Type: Grant
    Filed: October 7, 1991
    Date of Patent: April 20, 1993
    Assignee: GKSS-Forschungszentrum Geesthacht GmbH
    Inventors: Axel Wenzlaff, Dieter Behling, Karl W. Boddeker
  • Patent number: 5182022
    Abstract: Charge aqueous solution containing 85 w % ethylene glycol is concentrated by pervaporation across a sulfonated polyethylene membrane to yield retentate containing 95 w % ethylene glycol.
    Type: Grant
    Filed: June 19, 1991
    Date of Patent: January 26, 1993
    Assignee: Texaco Inc.
    Inventors: Mordechai Pasternak, John Reale, Jr.
  • Patent number: 5160413
    Abstract: Micro-distillation apparatus is provided for analyzing acidic anions in which the acidic anion sample is placed in a lower elongated member in water containing an acidifying material, upon heating the acidic anion leaves the lower member as a gas, passing through a permeable membrane into an upper elongated member containing a material which converts the acidic anion to a salt and the salt is recovered for analysis. The micro-distillation apparatus is sized so that a number of samples can be heated in a small heating member, such as a hot block heater.
    Type: Grant
    Filed: August 16, 1990
    Date of Patent: November 3, 1992
    Assignee: Conoco Inc.
    Inventor: Joe D. Allison
  • Patent number: 5152898
    Abstract: Concentration of solutions containing methanol and either dimethyl carbonate or methyl t-butyl ether may be effected by a composite membrane including a dibromobutane cross-linked poly(4-vinyl pyridine) bonded to a porous layer of polyacrylonitrile on a polyester backing.
    Type: Grant
    Filed: November 16, 1989
    Date of Patent: October 6, 1992
    Assignee: Texaco Inc.
    Inventor: Craig R. Bartels
  • Patent number: 5108549
    Abstract: A method of separating and recovering components of a mixture having a gap in the range of miscibility and including organic compounds and water in a pervaporization process with the aid of membranes. The mixture is first separated into an organically loaded water phase and a water-saturated organic phase. Subsequently, the organically loaded water phase and the water-saturated organic phase are separately subjected to parallel, different pervaporization processes, resulting in retentates as water on the one hand and organic liquid on the other hand. The permeates that result during the pervaporization processes are subsequently returned to the mixture that is to be separated.
    Type: Grant
    Filed: February 23, 1990
    Date of Patent: April 28, 1992
    Assignee: GKSS-Forschungszentrum Geesthacht GmbH
    Inventors: Axel Wenzlaff, Dieter Behling, Karl W. Boddeker
  • Patent number: 5062927
    Abstract: The method of preparing and operating a heat-exchanging membrane of plastic material as the evaporating and condensing surfaces in a still includes treating the evaporating surface to be wettable by the distilland, and includes selectively washing the condensing surface which is unwettable by the by the distilland in order to promote efficient accumulation of condensed droplets and efficient heat transfer through the membrane to the evaporation surface. Washing liquids of either similar or disimilar chemical composition relative to the condensed vapor are recycled to the upper region of the condensing surface to facilitate washing of the surface by the downward movement of accumulated droplets of condensed vapor.
    Type: Grant
    Filed: January 5, 1990
    Date of Patent: November 5, 1991
    Assignee: T and G Technologies, Inc.
    Inventor: Timothy R. Stout
  • Patent number: 5059327
    Abstract: A preparation membrane for pervaporation which comprises a crosslinked reaction mixture of a polyvinyl alcohol or polyvinyl alcohol copolymer and a polystyrene sulfonic acid or polystyrene sulfonic acid copolymer. A method for separating a mixture of water and an organic compound by using the membrane is also disclosed.
    Type: Grant
    Filed: August 25, 1987
    Date of Patent: October 22, 1991
    Assignee: Director-General, Agency of Industrial Science and Technology
    Inventor: Shinsuke Takegami
  • Patent number: 5028298
    Abstract: The present invention relates to a technique of concentrating waste water whereby the water content of the waste water is removed with a high decontamination factor, employs a porous membrane having a property allowing gas such as steam to permeate but not allowing a liquid such as water to do, as a membrane for concentrating the waste water, and adopts a method wherein the waste water is turned into a vapor flow and this vapor flow is made to contact the porous membrane so as for the waste water to be concentrated on the occasion when the waste water is to be concentrated by means of this porous membrane. By turning the waste water into the vapor flow, most of various metal ions, a surfactant, etc. existing in the waste water are separated from the vapor flow. Mist, metal ions in the mist and others contained in the vapor flow are removed by the aforesaid porous membrane from the steam while permeating the same.
    Type: Grant
    Filed: November 4, 1988
    Date of Patent: July 2, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Tsutomu Baba, Koichi Chino, Shunsuke Uchida, Toshio Sawa, Makoto Kikuchi
  • Patent number: 5022967
    Abstract: A microdistillation column for the quantitative steam distillation of cyanide, phenolic compounds, hydrogen fluoride, ammonia, sulfites and other volatile analyte compounds from samples of environmental waters and sludge for their subsequent analysis involves volatilizing the water in the sample tube of the microdistillation column. The pressure which develops due to the water vapor forces all volatile compounds from the water sample, including the water itself, through a hydrophobic membrane and into the collector tube of the microdistillation column. The volatile compounds and the water vapor condense in the cooler collector tube and are quantitatively trapped and retained over the membrane. Relatively small samples may be distilled in the column.
    Type: Grant
    Filed: September 18, 1989
    Date of Patent: June 11, 1991
    Assignee: Lachat Instruments
    Inventor: Scott Stieg
  • Patent number: 4978430
    Abstract: An improved method for dehydration and concentration of an aqueous solution containing an organic compound is disclosed. The solution is evaporated to produce a gaseous mixture comprising an organic compound vapor and a water vapor. The water vapor is selectively removed from the gaseous mixture by permeation through an aromatic polyimide gas separation membrane while the gaseous mixture being kept in contact with a surface on one side of the gas separation membrane at a temperature of 70.degree. C. or higher to obtain a gaseous mixture comprising the organic compound vapor and a reduced amount of a water vapor.
    Type: Grant
    Filed: July 24, 1989
    Date of Patent: December 18, 1990
    Assignee: UBE Industries, Ltd.
    Inventors: Kanji Nakagawa, Yoshio Asakura, Shigeru Yamamoto, Kohei Ninomiya, Masayuki Kinouchi
  • Patent number: 4953694
    Abstract: A distilling apparatus includes an evaporation section which heats raw water and causes the generation of vapor from said raw water, and a hydrophobic porous film through which the thus generated vapor is filtered. Because vapor separated from the raw water is supplied to one surface of the hydrophobic porous film, the proportion of the vapor relative to the fluid supplied to that surface of the film can be increased, thereby enabling the efficient filtering of a large amount of vapor through the film. In addition, because the temperature of condensed water obtained by cooling the vapor can be kept in the vicinity of the boiling point thereof, any gases and volatile substances contained in the raw water are prevented from dissolving in the distilled water, thereby enabling the production of extremely pure distilled water.
    Type: Grant
    Filed: June 17, 1988
    Date of Patent: September 4, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Nobuatsu Hayashi, Sankichi Takahashi, Katsuya Ebara, Hideaki Kurokawa, Akira Yamada, Yasuo Koseki, Harumi Matsuzaki, Hiroaki Yoda
  • Patent number: 4944881
    Abstract: A liquid separation membrane for pervaporation composed of a polymeric substance having in the main chain a glycosidic skeleton containing cationic groups and/or anionic groups at least some of which form a salt with counter anions and/or counter cations; and a method for pervaporation, which comprises separating a water-organic liquid mixture or an organic liquid-organic liquid mixture by pervaporation using a separation membrane, said membrane being composed of a polymeric substance having in the main chain a glycosidic skeleton containing cationic groups and/or anionic groups at least some of which form a salt with counter anions and/or counter cations and being dried so as to have a water content of not more than 25% by weight.
    Type: Grant
    Filed: November 29, 1988
    Date of Patent: July 31, 1990
    Assignee: Agency of Industrial Science and Technology
    Inventors: Akira Michizuki, Yoshio Sato, Hisashi Ogawara, Syuzo Yamashita
  • Patent number: 4936954
    Abstract: A liquid mixture is separated by pervaporation in an apparatus formed by a unitary stack of upright rectangular plates, diaphragms, and seals held together by tie rods. Each of the plates is formed with two upper and two lower corners formed with respective holes and each plate is formed inward of the respective holes with a corrugated central portion and the holes of the plates are aligned horizontally. Each diaphragm is sandwiched between two plates to form a cell having a pair of compartments separated by the respective diaphragm. The seals are arranged in the upstream region of the stack such that the liquid mixture enters one of the lower holes, passes downstream along the upstream portion into one of the compartments of each cell, and its lighter fraction passes as vapor through the diaphragms into the other compartments of these cells while its heavier fraction passes back upstream and exits the apparatus from one of the upper holes.
    Type: Grant
    Filed: August 29, 1988
    Date of Patent: June 26, 1990
    Assignee: Metallgesellschaft AG
    Inventor: Ulrich Sander
  • Patent number: 4900402
    Abstract: A pervaporation process for separating at least one component from a mixture of liquids, for example for separating ethanol from a fermentation mass, by a series of three separation steps: separating the mixture by a first pervaporation to form a first permeate vapor enriched in the component to be separated; fractionating the first permeate vapor, for example by temperature condensation, to form a high concentration fraction twice enriched in the component to be separated; and either distilling the high concentration fraction or a second pervaporation to form a distillate or retentate liquid thrice enriched in the component to be separated.
    Type: Grant
    Filed: March 25, 1987
    Date of Patent: February 13, 1990
    Assignee: Kernforschungszentrum Karlsruhe GmbH
    Inventors: Jurgen Kaschemekat, Frank Schutt, Axel Wenzlaff
  • Patent number: 4877533
    Abstract: Water is separated from a less hydrophilic fluid by contacting the mixture with one face of a membrane having an active layer which consists essentially only of polymers of an unsaturated organic acid with a ratio of carbon atoms to acid groups (not counting any carbon atoms in the acid groups) of not more than six. Water is removed as a vapor from the other side of the membrane.
    Type: Grant
    Filed: December 29, 1987
    Date of Patent: October 31, 1989
    Assignee: British Petroleum Company p.l.c.
    Inventors: Ian G. Meldrum, Timothy d. Naylor
  • Patent number: 4875980
    Abstract: Disclosed is a method for separating and concentrating an organic component having a lower boiling point than water from an aqueous solution containing the organic component which comprises the steps of (1) bringing an aqueous solution containing an organic component having a lower boiling point than water into contact with one surface of a hydrophobic porous membrane, continuously or intermittently evacuating the side of the porous membrane opposite to the aqueous solution to obtain a concentrated vapor of the organic component, and liquefying the vapor; and (2) bringing the resulting concentrated aqueous solution into contact with one surface of a hydrophobic nonporous membrane, evacuating the side of the non-porous membrane opposite to the concentrated aqueous solution to obtain a further concentrated vapor of the organic component, and liquefying the vapor.
    Type: Grant
    Filed: August 26, 1987
    Date of Patent: October 24, 1989
    Assignees: Mitsubishi Rayon Engineering Co., Ltd., Mitsubishi Rayon Co., Ltd.
    Inventors: Masujiro Arita, Yukinobu Sugimoto
  • Patent number: 4824573
    Abstract: A crosslinked composite membrane having high permeation velocity and separation factor and a process for producing the same. The membrane comprises a skin layer comprising a crosslinking reaction product of a water-soluble polysaccharide having a sulfonate group and/or a sulfonic acid group and a polyfunctional melamine compound. The crosslinked composite membrane can be formed on a porous base such as an ultrafilter.
    Type: Grant
    Filed: January 23, 1987
    Date of Patent: April 25, 1989
    Assignee: General Director of the Agency of Industrial Science and Technology
    Inventors: Zenjiro Honda, Hajime Komada, Hiroki Karakane
  • Patent number: 4818345
    Abstract: A distillation apparatus intended for distilling liquid, primarily water, comprising a distillation unit which includes a porous, hydrophobic membrane (2) which is pervious to steam, or vapor, but impervious to liquid, and a condensation surface (3) located at a distance from the membrane, such as to present an air gap (4) between the membrane and the condensation surface, the distillation apparatus further comprising units for conducting the liquid (20) to be distilled on the membrane surface remote from the air gap (4), and a unit for conducting a liquid (22) which is colder than the first mentioned liquid (20) on the side of the condensation surface (3) remote from the air gap (4). According to the invention the distance (L) between the membrane (2) and the condensation (3) lies in the range of about 0.2 mm-about 1 mm, and the thickness (b) of the membrane (2) is less than about 0.5 mm.
    Type: Grant
    Filed: February 10, 1987
    Date of Patent: April 4, 1989
    Inventor: Ann-Sofi Jonsson
  • Patent number: 4781837
    Abstract: A hydrophobic semi-permeable membrane process (e.g., using hydrophobic microporous hollow fibers) for the concentration of a dilute solution of low osmotic pressure by osmotic distillation (also known as membrane distillation or membrane evaporation), which is a separation process using as its driving force the difference in the osmotic pressure between two fluids (e.g., fruit juice and seawater) separated by a hydrophobic semi-permeable membrane to achieve a concentration of the fluid having the lower osmotic pressure (.e., fruit juice). When coupled with reverse osmosis means there is provided a method for recovery of solvent (e.g., potable water) from the process, e.g., desalination of seawater. A process is also provided to recover part of the energy available between the two fluids i.e., between two different potential energies, due to the difference in osmotic pressure between the two fluids.
    Type: Grant
    Filed: July 21, 1986
    Date of Patent: November 1, 1988
    Assignee: Limitinstant Limited
    Inventor: Michel S. M. Lefebvre
  • Patent number: 4778569
    Abstract: In a method and arrangement for separating a liquid mixture or a solution by converting a portion of the liquid mixture or portion of a solvent of the solution into a vapor phase and subsequent condensation of the obtained vapor with a porous separating wall, the pores of the porous separating wall are acted upon by a gas or gas mixture supplied through the pores of the porous separating wall in a counterstream to the vapor.
    Type: Grant
    Filed: January 8, 1986
    Date of Patent: October 18, 1988
    Assignee: AKZO nv.
    Inventor: Karl Ostertag
  • Patent number: 4746437
    Abstract: The method and apparatus for concentration aqueous solution in accordance with the present invention is characterized in that a hydrophobic porous membrane through which vapor can permeate, but not liquid, is brought into contact with an aqueous solution containing a solute at a concentration of at least 30%, and the water contained in the aqueous solution at the interface with the membrane is evaporated and permeates through the membrane. A method and an apparatus of recovering temperature of an aqueous solution comprising an aqueous solution concentration step in which the aqueous solution contact with the membrane, the water being evaporated; and a dilution step in which the resultant concentrated solution is diluted; wherein a temperature is obtained higher or lower than that of said aqueous solution.
    Type: Grant
    Filed: February 22, 1985
    Date of Patent: May 24, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Yasuo Koseki, Sankichi Takahashi, Katsuya Ebara, Osamu Kuroda, Hideaki Kurokawa
  • Patent number: 4728397
    Abstract: An apparatus for desalinating sea water, comprising a distillation unit which includes a porous hydrophobic membrane which is pervious to steam but impervious to water, and a condensation surface arranged at a distance from the membrane, the distillation arrangement also including a first unit for heating and conducting the water to be distilled on one side of the membrane, and a second unit arranged to conduct a liquid which is colder than the water, on the side of the condensation surface remote from the membrane, distilled water being collected and drawn-off between the membrane and the condensation surface.
    Type: Grant
    Filed: March 3, 1987
    Date of Patent: March 1, 1988
    Assignee: Svenska Utvecklings AB
    Inventors: Nils Kjellander, Bo Rodesjo
  • Patent number: 4718985
    Abstract: A system for diaphragm distillation of a liquid, for example for desalination of salt water, comprising a diaphragm, through which vapor, but not liquid can pass, and a condensation surface for condensing vapor having passed through the diaphragm, and necessary passageways. According to the invention, the system comprises one or several units, each of which comprises a plurality of pipes located one within the other, viz. a first (1) inner pipe, a second (2) pipe located outside thereof and consisting of a diaphragm of the aforesaid kind, and a third (3) pipe located outside the second (2) pipe, which first (1) and third (3) pipes are of a gas-tight material, that said unit is surrounded by a fourth (4) gas-tight pipe, where a first (5) passageway is formed by the first (1) pipe and a second (6), a third (7) and a fourth (8) passageway are formed between said pipes (1,2;2,3;3,4) in successive order in the direction from the inside outward.
    Type: Grant
    Filed: January 29, 1986
    Date of Patent: January 12, 1988
    Assignee: Svenska Utvecklings AB
    Inventor: Nils Kjellander
  • Patent number: 4698135
    Abstract: A system is provided for use adjacent a plant supporting material to be irrigated, for converting salt water into fresh water and dispensing the fresh water dripwise to the plant supporting material. The system comprises an evaporator member made of microporous hydrophobic material and having first and second surfaces, the microporous hydrophobic material permitting water vapor to diffuse through the member between the first and second surfaces thereof while preventing liquid water from passing therethrough, and a condenser including a condensing surface is spaced from the second surface of the evaporator member to define a gap therebetween. The condensing surface is in liquid flow communication with the plant supporting material to be irrigated. A conduit is provided for conducting a flow of salt water along the first surface of the evaporator members.
    Type: Grant
    Filed: October 3, 1985
    Date of Patent: October 6, 1987
    Assignee: Sirdan Research Limited
    Inventor: Simon Raab
  • Patent number: 4666564
    Abstract: Method and apparatus for distilling a liquid mixture to separate a volatile vapor fraction therefrom. The liquid is forced to flow along a meander-like path through a plurality of concentrically arranged chambers of a rotating drum. In the radially outermost chamber, a heating unit is provided which brings the liquid to a boiling temperature to allow formation of vapor. The liquid thus freed of volatile constituents is then discharged from the outermost chamber in which the liquid is subjected to a maximum centrifugal acceleration while the vapor moves radially inwardly under the action of the centripetal force to the innermost chamber from where the vapor containing volatile constituents is discharged.
    Type: Grant
    Filed: April 5, 1985
    Date of Patent: May 19, 1987
    Assignee: Fried. Krupp Gesellschaft mit beschrankter Haftung
    Inventor: Karl Zeitsch
  • Patent number: 4620900
    Abstract: A thermopervaporation apparatus comprising a microporous membrane which is impervious to liquids while readily allowing the vapor to pass therethrough, the passage of a hot feed solution situated on one side of said microporous membrane, a porous spacer disposed on at least part of the other side of said microporous membrane, and a heat-transmission wall disposed on said spacer, in such a manner that the vapor of the component to be separated from the feed solution permeates said membrane, diffuses to said heat-transmission wall through said spacer and is cooled on said heat-transmission wall to form a condensate which is withdrawn through said spacer, thereby improving a yield of the condensate.
    Type: Grant
    Filed: December 6, 1984
    Date of Patent: November 4, 1986
    Assignee: Nitto Electric Industrial Company Ltd.
    Inventors: Shoji Kimura, Shunichi Shimatani, Atsuo Yoshimura
  • Patent number: 4545862
    Abstract: A membrane distillation module is provided with a thin, flexible microporous membrane positioned against an impermeable condensor sheet that is stiffer in bending than the membrane. Distillate vapor diffuses through the membrane from the hot feed flowing rapidly past the membrane, and condenses and collects between, and in intimate contact with, the membrane and the condensor sheet. The condensed distillate is stripped by forces exerted by the hot feed acting on the distillate across the membrane, and flows toward a distillate outlet located in the downstream direction of the hot feed flow. Cold feed flows past the condensor sheet in the counter direction to that of the hot feed for absorbing the latent heat of condensation, and is subsequently additionally heated and introduced into the hot feed channel. Expanded microporous polytetrafluoroethylene (PTFE) is the preferred membrane material, and a spiral-wound assembly is the preferred configuration.
    Type: Grant
    Filed: March 5, 1982
    Date of Patent: October 8, 1985
    Assignee: W. L. Gore & Associates, Inc.
    Inventors: Wilbert L. Gore, Robert W. Gore, David W. Gore
  • Patent number: 4476024
    Abstract: A composite membrane structure is used in a distillation apparatus and method. The composite membrane separates a distilland and a distillate, such as salt water and fresh water. The composite membrane comprises a thin lyophobic microporous layer or membrane and a thin lyophilic layer or membrane. Evaporation and condensation takes place within the micropores of the lyophobic membrane. The lyophilic layer prevents intrusion of distilland into the pores of the lyophobic layer.
    Type: Grant
    Filed: August 9, 1982
    Date of Patent: October 9, 1984
    Assignee: International Power Technology, Inc.
    Inventor: Dah Y. Cheng
  • Patent number: 4419187
    Abstract: Apparatus and method for improved thermal membrane distillation utilizes a composite membrane comprised of a microporous lyophobic layer having deposited thereon an essentially nonporous lyophilic coating.
    Type: Grant
    Filed: March 4, 1982
    Date of Patent: December 6, 1983
    Assignee: International Power Technology, Inc.
    Inventors: Dah Y. Cheng, Steve J. Wiersma
  • Patent number: 4419242
    Abstract: A composite membrane separates a distilland and a distillate, such as salt water and fresh water. The composite membrane comprises a thin lyophobic microporous layer or membrane and a thin lyophilic layer or membrane on both sides of the lyophobic membrane or on the distillate side. Evaporation and condensation takes place within the micropores of the lyophobic membrane. The lyophilic layer on the distilland side prevents intrusion of distilland into the pores of the lyophobic layer. The lyophilic layer on the distillate side changes the surface curvature of the liquid/vapor interface in a manner which enhances the distillation rate through the membrane.
    Type: Grant
    Filed: February 18, 1982
    Date of Patent: December 6, 1983
    Assignee: International Power Technology, Inc.
    Inventors: Dah Y. Cheng, Steve J. Wiersma
  • Patent number: 4391676
    Abstract: An arrangement for permitting a first liquid to flow close to a second liquid, but without being intermixed therewith, includes a first plurality of plates (12) and a second plurality of plates (12), which are located between plates in the first plurality of plates but spaced therefrom by means of separating pieces. Each separating piece includes a frame formed about plate-shaped plane-parallel partial pieces, viz. an outer porous and hydrophobic plastic disphragm, an intermediate distance network of plastic and an outer thin plastic foil. The frame includes infeed holes for air and outfeed holes for water.The voids of the plastic diaphragm have a radius within the range of 2 to 5 .mu.m. The distance network has a thickness of 1 to 2 mm and consists of intersecting strips. The plastic foil has a thickness of about 0.1 mm.The plates include a frame with four through holes, of which two holes have connection to a recess in the plate, while the other two holes have no such connection.
    Type: Grant
    Filed: November 19, 1981
    Date of Patent: July 5, 1983
    Inventor: Finn Torberger
  • Patent number: 4344826
    Abstract: The waste water output of an RO unit in a distillation system is conveyed to a still's condenser cooling coil to minimize water requirements of the system. A portion of the heated water fron the condenser, in one embodiment, is circulated to the RO unit inlet, where a temperature mixing valve maintains an optimum temperature for the RO inlet water by mixing feed water and condenser output water in the desired proportions.
    Type: Grant
    Filed: June 20, 1980
    Date of Patent: August 17, 1982
    Assignee: Vaponics, Inc.
    Inventor: Verity C. Smith
  • Patent number: 4335576
    Abstract: A device for producing fresh water from salt sea water by utilizing the hydrodynamic energy of waves, comprising a buoyant platform; means for mooring the platform; a pump connected to the mooring means; a reservoir for pressurized sea water; a desalination system for extracting fresh water from the sea water; hydraulic flow control means for causing the pump to pump sea water into the sea water reservoir, as motion of the buoyant platform is produced due to the passing of waves beneath it; measuring means for measuring parameters of the sea adjacent the buoyant platform; and a control device connected to control the pressure in the sea water reservoir and the flow of sea water from the reservoir through the desalination system in response to the parameters of the sea.
    Type: Grant
    Filed: January 7, 1980
    Date of Patent: June 22, 1982
    Inventor: Harold H. Hopfe
  • Patent number: 4326923
    Abstract: Apparatus is provided for converting sea or other undrinkable waters to drinkable water without the use of driven or moving parts. Reliance upon gradient effects is made to effect the vaporization of, for example, sea water, followed by the condensation of the vapor to form distilled water. Gradient effects are achieved through the provision of differentials in the thermal conductivity, capillary activity, adsorptive, absorptive and/or pressure characteristics of particulate materials, or combinations of such physicals. For example, a column is packed with material graded as to its conductivity, the least thermally conductive material being nearest the cold or ambient water that is to be purified. In packing the column each successive layer of material has a greater thermal conductivity than the layer beneath it with the most conductive being at the top near the outlet arm of the column.
    Type: Grant
    Filed: January 9, 1980
    Date of Patent: April 27, 1982
    Inventor: Carl W. Mortenson
  • Patent number: 4316774
    Abstract: A urine-water recovery system is described which provides efficient potable water recovery from waste liquids. The design allows use over extended durations such as encountered in space flights. The system has advantages such as low power consumption, compactness, and gravity insensitive operation. The system comprises a vacuum distillation system combining a hollow fiber polysulfone membrane evaporator with a thermoelectric heat pump and condenser. With the system of the present invention, water purified from urine can be produced at a rate of more than 0.5 kg/hr at a total system energy of less than 400 w-hr/kg.
    Type: Grant
    Filed: July 5, 1979
    Date of Patent: February 23, 1982
    Assignee: United Technologies Corporation
    Inventor: Raymond B. Trusch