Membrane Patents (Class 62/624)
  • Patent number: 10293300
    Abstract: A natural-gas purification apparatus includes: a plurality of carbon-dioxide separation units that are arranged in series and separate carbon dioxide, through carbon-dioxide separation membranes, from natural gas pressurized by a compressor, cooled by a cooling unit to liquefy and separate a high-boiling-point hydrocarbon component, and heated by a heating unit; a gas supply pipe that is provided between the plurality of carbon-dioxide separation units through on-off valves and that supplies the natural gas; a compressor that is provided to the gas supply pipe; a cooling unit that liquefies and separates a high-boiling-point hydrocarbon component by cooling the natural gas pressurized by this compressor; and a heating unit that heats the natural gas after the separation of the high-boiling-point hydrocarbon component by this cooling unit.
    Type: Grant
    Filed: March 31, 2017
    Date of Patent: May 21, 2019
    Assignee: MITSUBISHI HEAVY INDUSTRIES, LTD.
    Inventors: Masayuki Eda, Wataru Matsubara, Shintaro Honjo, Susumu Okino, Hiromi Nakatani, Masaki Yushima
  • Patent number: 10246660
    Abstract: A natural-gas purification apparatus includes: a compressor that adjusts the pressure of natural gas from the ground; a cooling unit that liquefies and separates a part of natural-gas liquid by cooling the natural gas after the pressure adjustment by the compressor; a heating unit that heats the natural gas after the separation of the part; a carbon-dioxide separation unit that separates carbon dioxide from the natural gas heated by the heating unit; and an arithmetic control device that adjusts and controls at least one of the compressor, the cooling unit, and the heating unit to a value which has been set in advance according to the composition of the natural gas, such that the cooling unit will liquefy and separate the part of the natural-gas liquid in the natural gas and the carbon-dioxide separator maintains the remaining part of the natural-gas liquid in the natural gas in gaseous form.
    Type: Grant
    Filed: March 31, 2017
    Date of Patent: April 2, 2019
    Assignee: MITSUBISHI HEAVY INDUSTRIES, LTD.
    Inventors: Masayuki Eda, Wataru Matsubara, Shintaro Honjo, Susumu Okino, Hiromi Nakatani, Masaki Yushima
  • Patent number: 10208258
    Abstract: Closed loop filtration systems and methods of the present teachings can provide liquid reformable fuels enriched in light end hydrocarbons and/or having reduced content of sulfur and/or other impurities. Such enriched liquid reformable fuels can be used in fuel cell systems having a vaporizer and hydrocarbon fuel reformer such that the fuel cell system can experience less deleterious impact on its components, for example, coking. Filter elements for use in the systems and methods also are provided.
    Type: Grant
    Filed: March 5, 2015
    Date of Patent: February 19, 2019
    Assignee: WATT Fuel Cell Corp.
    Inventors: Caine Finnerty, Mathew Isenberg, Amanda Simson
  • Patent number: 9733014
    Abstract: The invention relates to a method and device for obtaining compressed oxygen and compressed nitrogen by the low-temperature separation of air in a distillation column system for nitrogen-oxygen separation, said distillation column system having at least one high-pressure column (8) and one low-pressure column (460), wherein the low-pressure column (460) is in a heat-exchanging connection with the high-pressure column (8) by means of a main condenser (461) designed as a condenser-evaporator. Feed air is compressed in an air compressor (2). The compressed feed air (6, 734, 802, 840) is cooled down in a main heat exchanger (20) and at least partially introduced into the high-pressure column (8). An oxygen-enriched liquid (462, 465) is removed from the high-pressure column (8) and fed to the low-pressure column (460) at a first intermediate position (464, 467, 906).
    Type: Grant
    Filed: August 9, 2011
    Date of Patent: August 15, 2017
    Assignee: LINDE AKTIENGESELLSCHAFT
    Inventors: Dirk Schwenk, Alexander Alekseev, Frances Masterson, Dimitri Goloubev
  • Patent number: 9636630
    Abstract: A gas separation method includes contacting a membrane filter with gas feed, permeating the gas from the gas feed through the membrane, and producing filtered gas from the filter. The filtered gas is produced from the filter as a result of the membrane removing any hydrocarbons containing six or more carbon atoms to produce a total of 0.001 ppm w/w or less. A gas separation method includes feeding gas into a filter containing a hollow fiber membrane that exhibits the property of resisting degradation due to exposure to hydrocarbons containing six or more carbon atoms. The filter exhibits a pressure drop across the membrane of less than 5 psi. The method includes feeding the filtered gas into a gas separation module that exhibits a susceptibility to degradation from exposure to hydrocarbons containing six or more carbon atoms.
    Type: Grant
    Filed: October 13, 2014
    Date of Patent: May 2, 2017
    Assignee: THE BOEING COMPANY
    Inventors: Barbara J Evosevich, Ivana Jojic
  • Patent number: 9555360
    Abstract: A device and method for producing a reformate fuel from a hydrocarbon gas source. The invention enables the conversion of a dilute hydrocarbon gas into a more easily consumable reformate fuel. Gases having low concentrations of hydrocarbons are concentrated using a concentrator into a gaseous or liquid concentrated VOC fuel. The concentrated VOC fuel is then converted into a reformate using a reformer. The reformate is more easily consumed by an energy conversion device such as a combustion engine, fuel cell, sterling engine or similar device that converts chemical energy into kinetic or electrical energy. The reformer enables complex hydrocarbon fuels that are not normally suitable for use in an energy conversion device to be converted into a reformate. The reformate may be directly supplied into the energy conversion device.
    Type: Grant
    Filed: April 26, 2011
    Date of Patent: January 31, 2017
    Assignee: DTE Energy
    Inventors: Patrick Ryan, Jeffery White, Mark Wherrett
  • Patent number: 9433887
    Abstract: The invention is a process involving membrane-based gas separation for separating and recovering carbon dioxide emissions from combustion processes in partially concentrated form, and then transporting the carbon dioxide and using or storing it in a confined manner without concentrating it to high purity. The process of the invention involves building up the concentration of carbon dioxide in a gas flow loop between the combustion step and a membrane separation step. A portion of the carbon dioxide-enriched gas can then be withdrawn from this loop and transported, without the need to liquefy the gas or otherwise create a high-purity stream, to a destination where it is used or confined, preferably in an environmentally benign manner.
    Type: Grant
    Filed: September 4, 2014
    Date of Patent: September 6, 2016
    Assignee: MEMBRANE TECHNOLOGY AND RESEARCH, INC.
    Inventors: Johannes G Wijmans, Richard W Baker, Timothy C Merkel
  • Patent number: 9211523
    Abstract: A fractionation system for a polymerization reactor includes a membrane separation system designed to separate light components, such as unreacted monomer and inerts, from diluent. The membrane separation system may employ one or more membrane modules designed to separate hydrocarbons based on size, solubility, or combinations thereof. The fractionation system also may include a heavies fractionation column designed to separate heavy components, such as unreacted comonomer and oligomers, from the diluent.
    Type: Grant
    Filed: July 1, 2010
    Date of Patent: December 15, 2015
    Assignee: Chevron Phillips Chemical Company LP
    Inventors: Andrew J. Mills, Ralph W. Romig, Andrea L. Hoener
  • Patent number: 9186614
    Abstract: An apparatus for producing hydrogen from an off-gas originating from a gas to liquid (GTL) process is provided. The apparatus includes a cryogenic distillation column, a first CO shift reactor, a second CO shift reactor, an SMR, and a first and second PSA. The cryogenic distillation column is configured to receive an off-gas and separate it into a light ends and a heavy ends. The first CO shift reactor is configured to receive the light ends and, in the presence of steam, produce additional hydrogen and carbon monoxide. The SMR is configured to receive the heavy ends and convert hydrocarbons within the heavy ends to hydrogen and CO, with the resulting stream then being treated in the second CO shift reactor to produce additional hydrogen and CO2. The hydrogen is then captured using the first and second PSAs.
    Type: Grant
    Filed: June 12, 2013
    Date of Patent: November 17, 2015
    Assignee: L'Air Liquide Société Anonyme Pour L'Etude Et L'Exploitation Des Procedes Georges Claude
    Inventor: Bhadra S. Grover
  • Patent number: 8555673
    Abstract: The invention relates to a method and apparatus for separating a mixture containing carbon monoxide, nitrogen and hydrogen by cryogenic distillation in a separation system which includes a denitrification column and at least another column. The method can include separating the mixture in order to obtain a fluid enriched with carbon monoxide and containing nitrogen, separating the fluid in the denitrification column, pressurizing the carbon monoxide flow from the column in a compressor up to a high pressure, collecting a fraction of carbon monoxide flow to be used as a product, expanding an amount of the high-pressure carbon monoxide flow in a valve prior to supplying it to the denitrification column, and varying the flow expanded in the valve according to re-boiling needs of the denitrification column.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: October 15, 2013
    Assignee: L'Air Liquide, Société pour l'Étude et l'Éxploitation des Procédés Georges Claude
    Inventors: Arthur Darde, Antoine Hernandez
  • Patent number: 8471087
    Abstract: Disclosed is a process for separating an acidic contaminant and light hydrocarbon of a light hydrocarbon feed having a large contaminating acidic contaminant content. Among other features, the process uses a combination of distillation and membrane separation arranged in a unique way to yield a high-purity light hydrocarbon product and a high-purity acidic contaminant product.
    Type: Grant
    Filed: May 17, 2010
    Date of Patent: June 25, 2013
    Assignee: Shell Oil Company
    Inventors: Zaida Diaz, Shu Shu, Paul Jason Williams
  • Patent number: 8337587
    Abstract: A process for the recovery of carbon dioxide from a gas mixture that includes pretreating a gas mixture comprising carbon dioxide, water vapor, and one or more light gases in a pretreating system to form a cooled gas mixture, fractionating the cooled gas mixture to recover a bottoms fraction comprising carbon dioxide and an overheads fraction comprising carbon dioxide and the light gases, passing the overheads fraction over a membrane selective to carbon dioxide to separate a carbon dioxide permeate from a residue gas comprising the light gases, recycling the carbon dioxide permeate to the pretreating system, and recovering at least a portion of the bottoms fraction as a purified carbon dioxide product stream is described.
    Type: Grant
    Filed: May 20, 2008
    Date of Patent: December 25, 2012
    Assignee: Lummus Technology Inc.
    Inventors: Loren E. Gearhart, Sanjiv N. Patel, David Koch
  • Patent number: 8177885
    Abstract: A gas separation process for treating exhaust gases from the combustion of gaseous fuels, and gaseous fuel combustion processes including such gas separation. The invention involves routing a first portion of the exhaust stream to a carbon dioxide capture step, while simultaneously flowing a second portion of the exhaust gas stream across the feed side of a membrane, flowing a sweep gas stream, usually air, across the permeate side, then passing the permeate/sweep gas back to the combustor.
    Type: Grant
    Filed: September 13, 2010
    Date of Patent: May 15, 2012
    Assignee: Membrane Technology and Research, Inc
    Inventors: Johannes G. Wijmans, Timothy C. Merkel, Richard W. Baker
  • Patent number: 8128733
    Abstract: A membrane-based gas separation process for treating gas streams that contain methane in low concentrations. The invention involves flowing the stream to be treated across the feed side of a membrane and flowing a sweep gas stream, usually air, across the permeate side. Carbon dioxide permeates the membrane preferentially and is picked up in the sweep air stream on the permeate side; oxygen permeates in the other direction and is picked up in the methane-containing stream. The resulting residue stream is enriched in methane as well as oxygen and has an EMC value enabling it to be either flared or combusted by mixing with ordinary air.
    Type: Grant
    Filed: May 11, 2009
    Date of Patent: March 6, 2012
    Assignee: Membrane Technology & Research, Inc
    Inventors: Johannes G. Wijmans, Timothy C. Merkel, Haiqing Lin, Scott Thompson, Ramin Daniels
  • Patent number: 8034168
    Abstract: Disclosed herein are combustion systems and power plants that incorporate sweep-based membrane separation units to remove carbon dioxide from combustion gases. In its most basic embodiment, the invention is a combustion system that includes three discrete units: a combustion unit, a carbon dioxide capture unit, and a sweep-based membrane separation unit. In a preferred embodiment, the invention is a power plant including a combustion unit, a power generation system, a carbon dioxide capture unit, and a sweep-based membrane separation unit. In both of these embodiments, the carbon dioxide capture unit and the sweep-based membrane separation unit are configured to be operated in parallel, by which we mean that each unit is adapted to receive exhaust gases from the combustion unit without such gases first passing through the other unit.
    Type: Grant
    Filed: April 22, 2011
    Date of Patent: October 11, 2011
    Assignee: Membrane Technology & Research, Inc
    Inventors: Johannes G. Wijmans, Timothy C Merkel, Richard W. Baker
  • Patent number: 8025715
    Abstract: A gas separation process for treating flue gases from combustion processes, and combustion processes including such gas separation. The invention involves routing a first portion of the flue gas stream to be treated to a carbon dioxide capture step, while simultaneously flowing a second portion of the flue gas across the feed side of a membrane, flowing a sweep gas stream, usually air, across the permeate side, then passing the permeate/sweep gas to the combustor.
    Type: Grant
    Filed: September 13, 2010
    Date of Patent: September 27, 2011
    Assignee: Membrane Technology and Research, Inc
    Inventors: Johannes G. Wijmans, Timothy C. Merkel, Richard W. Baker
  • Patent number: 8016923
    Abstract: Disclosed herein are combustion systems, power plants, and flue gas treatment systems that incorporate sweep-based membrane separation units to remove carbon dioxide from combustion gases. In its most basic embodiment, the invention is a combustion system that includes three discrete units: a combustion unit, a carbon dioxide capture unit, and a sweep-based membrane separation unit. In a preferred embodiment, the invention is a power plant including a combustion unit, a power generation system, a carbon dioxide capture unit, and a sweep-based membrane separation unit. In yet another embodiment, the invention is a flue gas treatment system that incorporates three membrane separation units with a carbon dioxide liquefaction unit.
    Type: Grant
    Filed: March 24, 2011
    Date of Patent: September 13, 2011
    Assignee: Membrane Technology and Research, Inc
    Inventors: Richard W. Baker, Johannes G Wijmans, Timothy C Merkel, Haiqing Lin, Ramin Daniels, Scott Thompson
  • Publication number: 20110174016
    Abstract: A process for treating offshore natural gas includes processing the natural gas on an off-shore processing facility by, (i) liquefying and fractionating the natural gas to generate a liquefied natural gas stream and a higher hydrocarbon stream, (ii) vapourising at least a portion of the higher hydrocarbon stream, (iii) passing the vapourised higher hydrocarbon stream and steam over a steam reforming catalyst to generate a reformed gas mixture comprising methane, steam, carbon oxides and hydrogen, (iv) passing the reformed gas mixture over a methanation catalyst to generate a methane rich gas, and (v) combining the methane-rich gas with the natural gas prior to the liquefaction step.
    Type: Application
    Filed: June 15, 2009
    Publication date: July 21, 2011
    Applicant: JOHNSON MATTHEY PUBLIC LIMITED COMPANY
    Inventors: Peter John Herbert Carnell, Ginny Yuen Che Ng
  • Patent number: 7964020
    Abstract: A gas separation process for treating flue gases from combustion processes, and combustion processes including such gas separation. The invention involves flowing the flue gas stream to be treated across the feed side of a membrane, flowing a sweep gas stream, usually air, across the permeate side, then passing the permeate/sweep gas to the combustor.
    Type: Grant
    Filed: May 8, 2009
    Date of Patent: June 21, 2011
    Assignee: Membrane Technology & Research, Inc
    Inventors: Richard W Baker, Johannes G Wijmans, Timothy C Merkel, Haiqing Lin, Ramin Daniels, Scott Thompson
  • Patent number: 7638059
    Abstract: The present invention relates to an oxygen isotope separation system and a method therefor. More specifically, the invention relates to a newly invented pressure-driven AGMD (Air Gap Membrane Distillation) system applied to a multi-stage membrane distillation cells which can produce an oxygen isotope effectively and economically, and a method therefor. The invention provides an oxygen isotope separation system including a number of Air Gap Membrane Distillation (AGMD) permeation cells connected in series to separate a feed into a product and a tail, wherein each of the AGMD cell is connected at a tail outlet with a reflux pump and at a product outlet, whereby the product from (i?1)th cell and the tail from (i+1)th cell are pumped as the feed into ith cell.
    Type: Grant
    Filed: February 2, 2007
    Date of Patent: December 29, 2009
    Assignee: Korea Atomic Energy Research Institute
    Inventors: JaeWoo Kim, Hwa-Rim Choi, Dae-Shik Chang, Yun-Young Choi
  • Patent number: 7263858
    Abstract: The present invention provides generally a method and apparatus for purifying a liquid. More particularly, purification of a bulk liquid is performed by introducing a liquid stream to a purification vessel, which comprises both a distillation chamber for forming a purified vapor and an annular chamber for collecting a purified liquid that is condensed from the purified vapor. A refrigerant system provides thermodynamic efficiency in the purification method by directing waste heat generated in one part of the refrigerant system for heating duty in another part of the refrigerant system. The method and apparatus can be applied to producing purified carbon dioxide, nitrous oxide, ammonia and fluorocarbons.
    Type: Grant
    Filed: May 20, 2005
    Date of Patent: September 4, 2007
    Assignee: The BOC Group, Inc.
    Inventor: Walter Whitlock
  • Patent number: 7152430
    Abstract: A method of separating CO2 from a hydrocarbon gas inlet stream that is within predetermined pressure and temperature ranges including the steps of subjecting the inlet stream to fractional distillation providing a bottom product stream and a distillation overhead stream, passing the distillation overhead stream to a membrane unit producing a CO2 by-product stream and a hydrocarbon stream and chilling the hydrocarbon stream to produce a reflux liquid stream and a hydrocarbon gas product.
    Type: Grant
    Filed: March 9, 2004
    Date of Patent: December 26, 2006
    Assignee: National Tank Company
    Inventor: David Parro
  • Patent number: 7124605
    Abstract: A method of separating CO2 from a hydrocarbon gas inlet stream that is within predetermined pressure and temperature ranges, including the steps of subjecting the inlet stream to fractional distillation providing a CO2 bottom product stream and a distillation overhead stream, passing the distillation overhead stream to the inlet of a primary reflux drum producing a primary reflux liquid stream and a hydrocarbon vapor stream, subjecting the hydrocarbon vapor stream to membrane separation to provide a hydrocarbon product stream and a permeate stream, compressing the permeate stream and recycling the compressed permeate stream to the inlet of the primary reflux drum thereby providing a CO2 liquid product and a hydrocarbon gas product.
    Type: Grant
    Filed: October 30, 2003
    Date of Patent: October 24, 2006
    Assignee: National Tank Company
    Inventors: David Parro, Edgar S. Sanders, Jr.
  • Patent number: 6568206
    Abstract: A process for recovering a first component and/or a second component from a multicomponent feed gas mixture containing the first component and the second component includes multiple steps. The first step is to pass the feed gas mixture through a membrane separation unit, thereby separating the feed gas mixture into a first stream enriched in the first component and a second stream lean in the first component. The second step is to cool the first stream. The third step is to expand the cooled first stream in a work extraction device, thereby generating a refrigeration supply for the process.
    Type: Grant
    Filed: July 18, 2001
    Date of Patent: May 27, 2003
    Assignee: Air Products and Chemicals, Inc.
    Inventor: Eric William Scharpf
  • Patent number: 6425267
    Abstract: A process for treating natural gas or other methane-rich gas to remove excess nitrogen. The invention relies on membrane separation using methane-selective membranes, but does not require the membranes to be operated at very low temperatures. We have found that, by using a two-step membrane system design, and controlling the operating pressures for the membrane steps within certain ranges, the capital and operating costs of the process can be kept within economically acceptable limits.
    Type: Grant
    Filed: July 27, 2001
    Date of Patent: July 30, 2002
    Assignee: Membrane Technology and Research, Inc.
    Inventors: Richard W. Baker, Kaaeid A. Lokhandwala, Johannes G. Wijmans, Andre R. Da Costa
  • Publication number: 20010035026
    Abstract: A method for generating refrigeration for application to a heat load, especially at very cold temperatures, using an environmentally benign working gas such as air and using an upstream precooling circuit to reduce or eliminate inefficiencies stemming from warm end pinch.
    Type: Application
    Filed: March 21, 2001
    Publication date: November 1, 2001
    Inventors: Dante Patrick Bonaquist, Harry Cheung, Arun Acharya
  • Patent number: 6289693
    Abstract: A system and process for the production of synthesis gas with a specific H2CO ratio, for example, 0.7 to 1.2 and a low residual methane content, for example, less than 5 percent (5%). Excess hydrogen from the syngas feed stream is removed by a membrane as a permeate and the retentate gas cryogenically separated.
    Type: Grant
    Filed: January 25, 2000
    Date of Patent: September 18, 2001
    Assignee: Chart Industries, Inc.
    Inventor: John V. O'Brien
  • Patent number: 6205813
    Abstract: A natural gas purification system which can produce both fuel and high purity hydrocarbon product such as high purity methane or high purity natural gas wherein high temperature carbon dioxide removal is followed by cryogenic rectification to produce fuel and high purity hydrocarbon product.
    Type: Grant
    Filed: July 1, 1999
    Date of Patent: March 27, 2001
    Assignee: Praxair Technology, Inc.
    Inventors: Minish Mahendra Shah, James Joseph Maloney, Raymond Francis Drnevich
  • Patent number: 6192706
    Abstract: A system for producing carbon monoxide wherein a carbon monoxide containing feed stream is processed in a membrane separation unit for partial removal of carbon dioxide, cooled to complete the removal of carbon dioxide, and then processed in a cryogenic separation system comprising a first cryogenic separation column and a second cryogenic separation column for the production of product carbon monoxide.
    Type: Grant
    Filed: October 5, 1999
    Date of Patent: February 27, 2001
    Assignee: Praxair Technology, Inc.
    Inventors: Thomas John Bergman, Jr., John Fredric Billingham, Michael Robert Couche, Minish Mahendra Shah
  • Patent number: 6173585
    Abstract: An apparatus for the cryogenic separation of a mixture containing at least hydrogen, carbon monoxide and methane comprises two phase separators (A, H), two heat exchangers (D, K) and two stripping columns (B, I). The mixture cooled in the first exchanger is sent into a phase separator and at least some of the condensed fraction is sent into the first stripping column (B). At least some of the head gas from the stripping column is sent into the second phase separator (H) and the liquid produced is sent into the head of the second stripping column (I). The base liquid from the first stripping column may be sent into a purification column (C).
    Type: Grant
    Filed: June 28, 1999
    Date of Patent: January 16, 2001
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Jean Billy, Francois Fuentes, Nathalie Sosson
  • Patent number: 6161397
    Abstract: Gas mixtures are separated by cryogenic separation, preferably a cryogenic condensation separation cycle, into at least a first gas mixture and a second gas mixture having at least one component common with the first gas mixture; at least one gas mixture selected from at least a portion of said feed gas mixture and at least a portion of said second gas mixture is subjected to non-cryogenic separation to provide a separated gas rich in said common component; and said separated gas is added to said first gas mixture to contribute to a product gas mixture. It is particularly preferred to also blend a portion of the second gas mixture with the first gas mixture to facilitate, in conjunction with the separated stream, simultaneous control of both the amount and composition of the first gas mixture product.
    Type: Grant
    Filed: August 12, 1998
    Date of Patent: December 19, 2000
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Brian Alfred McNeil, Eric William Scharpf, David Graham Winter
  • Patent number: 6141988
    Abstract: A process for recovering olefins from a gas stream containing olefins and hydrogen. The process comprises compressing the gas stream in at least one compression stage to form a compressed gas stream, contacting the compressed gas stream with a membrane at conditions effective to obtain a permeate stream rich in hydrogen and a retentate stream depleted in hydrogen, and introducing the permeate stream into a pressure swing adsorption system at conditions effective to obtain a nonadsorbed stream rich in hydrogen and a desorbed stream comprising olefins.
    Type: Grant
    Filed: December 9, 1998
    Date of Patent: November 7, 2000
    Assignees: Air Liquide America Corporation, L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Yves Engler, Gerard Dupuis
  • Patent number: 6128919
    Abstract: A process for separating natural gas and carbon dioxide from a raw feed stream, such as in carbon dioxide for EOR processes. Separation is by membrane separation at low pressures. By utilizing low pressure separation, highly selective membranes can be used and recycling becomes practical.
    Type: Grant
    Filed: September 22, 1998
    Date of Patent: October 10, 2000
    Assignee: Messer Griesheim Industries, Inc.
    Inventors: Paul A. Daus, Charles R. Pauley, deceased
  • Patent number: 6085549
    Abstract: A process for producing carbon dioxide from a gas stream containing same pretreats the incoming raw gas to remove contaminants and particularly to protect degradation of the membranes utilized for separation. The temperatures of the various gas streams are carefully controlled to reduce water from the stream. By-product and other gas streams of the process are recycled in order to increase efficiency by utilizing the heating or cooling properties of the streams. In addition, streams containing minor portions of carbon dioxide are returned to the system for recovery.
    Type: Grant
    Filed: April 8, 1998
    Date of Patent: July 11, 2000
    Assignee: Messer Griesheim Industries, Inc.
    Inventors: Paul A. Daus, Charles R. Pauley, John W. Koenst, Fred Coan
  • Patent number: 6065306
    Abstract: Ammonia is purified by a membrane unit to concentrate ammonia and/or ammonia and moisture. Moisture is removed in a temperature-swing adsorption unit. The resultant product of such purification is then partially condensed to remove light components of other impurities and then partially vaporized to produce a pressurized ammonia product lean in heavy components. If the feed stream is processed through the membrane unit first, the permeate stream will be lean in such impurities as carbon dioxide, nitrogen and methane. Moisture and any carbon dioxide not removed in the membrane unit is then removed by the adsorption unit. The resultant stream produced by action of the membrane and adsorption units is then partially condensed to produce a liquid lean in light impurities. Such liquid is then partially vaporized within a product pressure vessel to produce ammonia vapor lean in heavy impurities and at a required operational pressure.
    Type: Grant
    Filed: May 19, 1998
    Date of Patent: May 23, 2000
    Assignee: The BOC Group, Inc.
    Inventors: Wenchang Ji, Arthur I. Shirley, Atul M. Athalye, Piotr J. Sadkowski
  • Patent number: 6047561
    Abstract: A device and a process for preparing a high-purity inert gas from air, includes the successive steps of:a) cryogenically distilling compressed air,b) recovering an impure inert fluid containing hydrogen impurities (H.sub.2) and residual impurities,c) adsorbing at least some of the residual impurities contained in the impure inert fluid by at least one bed of at least one adsorbent,d) recovering an intermediate inert fluid containing hydrogen impurities,e) removing the hydrogen impurities contained in the intermediate inert fluid by permeation, andf) recovering a high-purity inert fluid in the gas state.
    Type: Grant
    Filed: July 27, 1998
    Date of Patent: April 11, 2000
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Daniel Gary, Rene Lardeau, Jean-Yves Thonnelier
  • Patent number: 6032484
    Abstract: A method for the separation and recovery of fluorochemicals from a gas stream containing a diluent gas and fluorochemicals by first contacting the gas stream with a membrane system in one or more stages where the membrane(s) is selectively more permeable to the diluent gas than the fluorochemicals to result in a permeate stream rich in diluent gas and retentate rich in fluorochemicals, thereafter subjecting retentate the gas stream to a purification by distillation or adsorption resulting in a product stream enriched in fluorochemicals and a purified diluent stream. The purified diluent stream is used as a purge stream and/or a recycle stream together with the permeate stream to a vacuum pump upstream of the membrane separation step.
    Type: Grant
    Filed: March 23, 1998
    Date of Patent: March 7, 2000
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Iosif Chernyakov, Thomas Hsiao-Ling Hsiung, Alexander Schwarz, James Hsu-Kuang Yang
  • Patent number: 5979178
    Abstract: A process for recovering olefins from a cracking effluent containing olefins and hydrogen. The process comprises compressing the cracking effluent in at least one compression stage to form a compressed cracking effluent, contacting the compressed cracking effluent with a membrane at conditions effective to obtain a permeate stream rich in hydrogen and a retentate stream depleted in hydrogen, and introducing the permeate stream into a pressure swing adsorption system at conditions effective to obtain a nonadsorbed stream rich in hydrogen and a desorbed stream comprising olefins.
    Type: Grant
    Filed: December 16, 1997
    Date of Patent: November 9, 1999
    Assignees: Air Liquide America Corporation, L'air Liquide Societe Anonyme pour L'etude et L'exploitation des procedes Georges Claude
    Inventors: Yves Engler, Gerard Dupuis
  • Patent number: 5669958
    Abstract: A membrane separation process for treating a gas stream containing methane and nitrogen, for example, natural gas. The separation process works by preferentially permeating methane and rejecting nitrogen. We have found that the process is able to meet natural gas pipeline specifications for nitrogen, with acceptably small methane loss, so long as the membrane can exhibit a methane/nitrogen selectivity of about 4, 5 or more. This selectivity can be achieved with some rubbery and super-glassy membranes at low temperatures. The process can also be used for separating ethylene from nitrogen.
    Type: Grant
    Filed: February 29, 1996
    Date of Patent: September 23, 1997
    Assignee: Membrane Technology and Research, Inc.
    Inventors: Richard W. Baker, Kaaeid A. Lokhandwala, Ingo Pinnau, Scott Segelke
  • Patent number: 5647227
    Abstract: A membrane separation process combined with a cryogenic separation process for treating a gas stream containing methane, nitrogen and at least one other component. The membrane separation process works by preferentially permeating methane and the other component and rejecting nitrogen. The process is particularly useful in removing components such as water, carbon dioxide or C.sub.3+ hydrocarbons that might otherwise freeze and plug the cryogenic equipment.
    Type: Grant
    Filed: February 29, 1996
    Date of Patent: July 15, 1997
    Assignee: Membrane Technology and Research, Inc.
    Inventor: Kaaeid Lokhandwala
  • Patent number: 5634354
    Abstract: Olefins are recovered from thermally cracked gas or fluid catalytic cracking off gas by cooling the gas to condense a portion of the hydrocarbons, removing hydrogen from the noncondensed gas, and condensing the remaining hydrocarbons in a cold condensing zone using a dephlegmator which operates above about -166.degree. F. This mode of operation minimizes the amount of methane in the condensate which is further processed in demethanizer column(s) and permits the condensation of ethylene at warmer temperatures than possible using a partial condenser in the cold condensing zone. The use of a dephlegmator at temperatures above about -166.degree. F. minimizes or eliminates the formation and accumulation of unstable nitrogen compounds in the ethylene recovery system. Hydrogen is removed from the noncondensed gas in a process selected from polymeric membrane permeation, adsorptive membrane permeation, or pressure swing adsorption.
    Type: Grant
    Filed: May 8, 1996
    Date of Patent: June 3, 1997
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Lee J. Howard, Howard C. Rowles