Recycle Patents (Class 62/631)
  • Patent number: 11884621
    Abstract: A process for the separation of a natural gas stream is provided. The process includes receiving an effluent gas flow from a first fractionator operating at a first pressure, splitting the effluent gas flow into a first stream and a second stream, and passing the first stream through a heat exchanger thereby causing a phase change of at least a portion of the first stream from a gaseous state to a liquid state. The process includes inserting the first stream into an upper portion of a second fractionator operating at a second pressure. The second pressure is lower than the first pressure. The process includes inserting the second stream into a lower portion of the second fractionator, and diverting liquids from a lower portion of the second fractionator to the first fractionator.
    Type: Grant
    Filed: March 25, 2022
    Date of Patent: January 30, 2024
    Assignee: Enerflex US Holdings Inc.
    Inventor: Timothy W. Oneal
  • Patent number: 11274256
    Abstract: Provided are an apparatus and a method for separation and recovery of propane and heavier hydrocarbons from LNG. The apparatus has, from the upstream side toward the downstream side of LNG supply, first column (3) equipped with first column overhead condenser (2), first column bottom reboiler (4) and side reboiler (5), and second column (14) equipped with second column overhead condenser (11) and second column bottom reboiler (15). The first column (3) separates methane and a part of ethane as an overhead vapor and separates remaining ethane and C3 or higher hydrocarbons as a bottom liquid. The second column (14) separates ethane as an overhead vapor and separates C3 or higher hydrocarbons as a bottom liquid.
    Type: Grant
    Filed: October 23, 2018
    Date of Patent: March 15, 2022
    Assignee: TOYO ENGINEERING CORPORATION
    Inventors: Shoichi Yamaguchi, Yasuyuki Yamamori, Xiaoxue Zhang
  • Patent number: 10017434
    Abstract: Gas separation processes are provided for separating dehydrogenation reaction products from a raw gas stream to recover hydrocarbons, specifically olefins, such as propylene and iso-butene, as well as unreacted feedstock. The processes employ a sequence of partial condensation steps, interspersed with membrane separation steps to raise the hydrocarbon dewpoint of the uncondensed gas, thereby avoiding the use of low-temperature or cryogenic conditions.
    Type: Grant
    Filed: September 21, 2016
    Date of Patent: July 10, 2018
    Assignee: Membrane Technology and Research, Inc.
    Inventors: Nicholas P Wynn, Alvin Ng, Douglas Gottschlich, Paul Su, Meijuan Zhou, Sylvie Thomas-Droz
  • Patent number: 9739485
    Abstract: The invention relates to a unit for the purification of a gas flow comprising CO and at least 45% CO2 and a method of operating said unit. In one embodiment, said unit contains a first compressor, a heat exchanger configured to cool the compressed gas flow, a separation chamber configured to separate head gas produced in the heat exchanger, a heater disposed on the line of the head gas originating from the separation chamber, a catalytic oxidation unit for oxidizing the compressed CO in the gas flow originating from the heater, and turbines placed downstream of the catalytic oxidation unit.
    Type: Grant
    Filed: September 25, 2013
    Date of Patent: August 22, 2017
    Assignee: L'Air Liquide Société Anonyme Pour L'Étude Et L'Exploitation Des Procedes Georges Claude
    Inventors: Nicolas Chambron, Arthur Darde, Richard Dubettier-Grenier, Mathieu Leclerc
  • Patent number: 8910495
    Abstract: Devices and methods for retrofitting a natural gas liquids plant are contemplated to extend recovery of C3+ hydrocarbons from various feed gases to recovery of C2+ and C3+ hydrocarbons. In especially preferred aspects, dedicated C2+ exchangers are integrated to exclusively cool the feed gas to produce a cooled absorber feed and to produce two separate absorber reflux streams. During C2+ recovery, absorber reflux is provided by a portion of the residue gas and a portion of the feed gas, while during C3+ recovery absorber and distillation column reflux are provided by the distillation column overhead product.
    Type: Grant
    Filed: June 20, 2012
    Date of Patent: December 16, 2014
    Assignee: Fluor Technologies Corporation
    Inventor: John Mak
  • Patent number: 8840707
    Abstract: A gas condensate production plant comprises a plurality of separation units in which C2 and/or C3 lighter components are stripped from the separator feeds using compressed heated stripping vapor produced from the feed in respective downstream separation units. Contemplated plants substantially reduce heating and cooling duties by using the waste heat from the compressor discharges in the separation process. Furthermore, the multi-stage fractionation according to the inventive subject matter provides improved gas condensate recovery at reduced energy costs.
    Type: Grant
    Filed: June 22, 2005
    Date of Patent: September 23, 2014
    Assignee: Fluor Technologies Corporation
    Inventor: John Mak
  • Patent number: 8695376
    Abstract: Contemplated plant configurations and methods employ a vaporized and supercritical LNG stream at an intermediate temperature that is expanded, wherein refrigeration content of the expanded LNG is used to chill one or more recompressor feed streams and to condense a demethanizer reflux. One portion of the so warmed and expanded LNG is condensed and fed to the demethanizer as reflux, while the other portion is expanded and fed to the demethanizer as feed stream. Most preferably, the demethanizer overhead is combined with a portion of the vaporized and supercritical LNG stream to form a pipeline product.
    Type: Grant
    Filed: December 20, 2007
    Date of Patent: April 15, 2014
    Assignee: Fluor Technologies Corporation
    Inventor: John Mak
  • Patent number: 8552245
    Abstract: This method includes the separation of an upstream partly condensed cracked gas stream in an intermediate separator (44B) in order to recover an intermediate liquid (136), and an intermediate cracked gas stream (138) and the introduction of the intermediate liquid (140) into an intermediate demethanization column (68). The method comprises the sampling of a portion of the intermediate liquid (136) and the expansion of at least one first fraction (194) obtained from the sampled portion (190). It comprises the putting of the first expanded fraction in a heat exchange relationship with the intermediate head stream (146) from the column (68) for at least partly condensing the intermediate head stream (146). The method includes the separation of the intermediate partly condensed head stream in a first reflux separator (76) in order to form a liquid stream (148) introduced into the intermediate column (68) and a combustible gas stream (150).
    Type: Grant
    Filed: March 28, 2011
    Date of Patent: October 8, 2013
    Assignee: Technip France
    Inventors: Yvon Simon, Jean-Paul Laugier
  • Patent number: 8505333
    Abstract: An LNG facility employing an optimized heavies removal system. The optimized heavies removal system can comprise at least one distillation column and at least two separate heat exchangers. The heat exchangers can be operable to heat a liquid stream withdrawn from a distillation column to thereby provide predominantly vapor and/or liquid streams that can be reintroduced into the column.
    Type: Grant
    Filed: December 9, 2008
    Date of Patent: August 13, 2013
    Assignee: ConocoPhilips Company
    Inventors: Megan V. Evans, Attilio J. Praderio, Lisa M. Strassle, Mohan S. Chahal, Matthew C. Gentry, Wesley R. Qualls, Marc T. Bellomy, James L. Rockwell
  • Patent number: 8256243
    Abstract: Methods and apparatus for the integration of a fractionation process and an olefin refrigeration system, wherein the fractionation process olefin effluent is supplied to the refrigeration system, can eliminate a fractionation process condenser and reflux drum typically present. A plurality of bottoms streams can be collected from the fractionation process. The olefin refrigerant can be supplied to alternate olefin refrigerant consumers, as desired. A column in the fractionation process can be refluxed with an olefin stream from refrigeration system, and olefin product can be collected or exported via line.
    Type: Grant
    Filed: December 16, 2006
    Date of Patent: September 4, 2012
    Assignee: Kellogg Brown & Root LLC
    Inventor: Vijender Kumar Verma
  • Patent number: 8075742
    Abstract: An apparatus and process for the separation of refrigerant mixtures is provided. The apparatus includes a first distillation column, a first condenser, and a first collection vessel. The apparatus also includes a sorter vessel that includes a sorter agent, wherein the sorter vessel is fluidly connected to the first distillation column.
    Type: Grant
    Filed: December 3, 2009
    Date of Patent: December 13, 2011
    Assignee: Midwest Refrigerants, LLC
    Inventor: Gregorio Tarancon, III
  • Patent number: 7856848
    Abstract: The present invention related to a flexible hydrocarbon gas separation process that could dehydrate the water-saturated hydrocarbon gas mixture and recover thereof the required higher hydrocarbons (NGL) therein with a controllable ethane recovery rate (ranging from >95% to <2%) while keeping high recovery rate of all other heavier components. The flexible process comprises the following steps: deep-cooling and dehydrating the raw gas and get the NGL condensate; flowing the deep-dehydrated gas into the flexible absorber to get the rich oil with desirable ethane content; completely demethanizing and partially deethanizing as desired the rich oil and the NGL condensate to get purified rich oil and purified NGL condensate, respectively; separating the NGL vapor from the purified rich oil; cooling and compressing the NGL vapor; mixing the NGL vapor with the purified NGL condensate; and liquefying the mixture to get the final NGL product.
    Type: Grant
    Filed: March 5, 2007
    Date of Patent: December 28, 2010
    Inventor: Yingzhong Lu
  • Publication number: 20100223952
    Abstract: A process and apparatus for producing a carbon monoxide-containing product from a feed containing hydrogen, carbon monoxide, methane, nitrogen and optionally argon. The carbon monoxide-containing product is produced using a hydrogen stripping column for forming a hydrogen-enriched vapor and a hydrogen-freed liquid, a nitrogen separation fractionator for forming a nitrogen-enriched vapor and a nitrogen-depleted liquid containing carbon monoxide and methane from the hydrogen-freed liquid, and a carbon monoxide/methane separation fractionator for forming the carbon monoxide containing product and a methane-enriched liquid from the nitrogen-depleted liquid. At least part of the nitrogen separation fractionator condenser duty provides the feed vaporization duty and reboiler duty for the carbon monoxide/methane separation fractionator, thereby reducing the energy requirement for the separation.
    Type: Application
    Filed: March 3, 2009
    Publication date: September 9, 2010
    Applicant: AIR PRODUCTS AND CHEMICALS, INC.
    Inventor: Brian Alfred McNeil
  • Patent number: 7707852
    Abstract: The present invention concerns a process for recovering lower carbon olefins from MTO or DTO product gas. Said process primarily comprises the product gas compressing, pre-deethanizing, demethanizing and ethylene recovering apparatus, depropanizing column, ethylene rectification column, propylene rectification column and the like. In addition, the process of the present invention needs no independent ethylene cooling system, and the ethylene recovery rate may achieve 99.5%.
    Type: Grant
    Filed: September 29, 2006
    Date of Patent: May 4, 2010
    Assignees: China Petroleum & Chemical Corporation, Sinopec Engineering Incorporation
    Inventors: Zhenwei Wang, Zaihang Sheng, Xueliang Zhao
  • Publication number: 20100043489
    Abstract: A method for separating a mixture of carbon monoxide, methane, hydrogen and optionally nitrogen by cryogenic distillation is provided.
    Type: Application
    Filed: December 14, 2007
    Publication date: February 25, 2010
    Inventors: Arthur Darde, Natacha Halk-Beraud, Antoine Hernandez, Guillaume Teixeira
  • Publication number: 20090301132
    Abstract: An LNG facility employing an optimized heavies removal system. The optimized heavies removal system can comprise at least one distillation column and at least two separate heat exchangers. The heat exchangers can be operable to heat a liquid stream withdrawn from a distillation column to thereby provide predominantly vapor and/or liquid streams that can be reintroduced into the column.
    Type: Application
    Filed: December 9, 2008
    Publication date: December 10, 2009
    Applicant: CONOCOPHILLIPS COMPANY
    Inventors: Megan V. Evans, Attilio J. Praderio, Lisa M. Strassle, Mohan S. Chahal, Matthew C. Gentry, Wesley R. Qualls, Marc T. Bellomy, James L. Rockwell
  • Patent number: 7617701
    Abstract: In a process for producing a mixture containing at least 10% carbon monoxide (73) by cryogenic separation of a feed gas containing at least carbon monoxide, hydrogen and methane, the feed gas (1) is separated to produce a first gas enriched in hydrogen (71), the feed gas is scrubbed in a methane wash column (7), a carbon monoxide enriched stream (13) from the bottom of the methane wash column is separated (19) to produce a stream further enriched in carbon monoxide (23), the stream further enriched in carbon monoxide is separated to form a carbon monoxide rich stream (31,49) and a liquid methane stream (27), at least part (72) of the carbon monoxide rich stream is mixed with the first gas enriched in hydrogen to form the mixture containing at least 10% carbon monoxide as a product stream.
    Type: Grant
    Filed: April 7, 2004
    Date of Patent: November 17, 2009
    Assignee: L'Air Liquide, Societe Anonyme a Directoire et Conseil de Surveillance pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Jean Billy, Natacha Haik-Beraud, Jean Gallarda, Franck Wegrzyn
  • Patent number: 7565815
    Abstract: A process for liquefying natural gas in conjunction with producing a liquid stream containing predominantly hydrocarbons heavier than methane is disclosed. In the process, the natural gas stream to be liquefied is partially cooled, expanded to an intermediate pressure, and supplied to a distillation column. The bottom product from this distillation column preferentially contains the majority of any hydrocarbons heavier than methane that would otherwise reduce the purity of the liquefied natural gas. The residual gas stream from the distillation column is compressed to a higher intermediate pressure, cooled under pressure to condense it, and then expanded to low pressure to form the liquefied natural gas stream.
    Type: Grant
    Filed: February 16, 2007
    Date of Patent: July 28, 2009
    Assignee: Ortloff Engineers, Ltd.
    Inventors: John D. Wilkinson, Hank M. Hudson, Kyle T. Cuellar
  • Patent number: 7458232
    Abstract: This method comprises the cooling of the initial natural gas and its introduction into a column for recovering C2+ hydrocarbons. It comprises the recovery of the top stream from the column to form the treated natural gas, and the recovery of the bottom stream from the column for introducing it at a feed level of a fractionating column equipped with a top condenser. The column produces the said C3+ hydrocarbons at the bottom. The method comprises the recovery of the ethane rich stream from an intermediate level of the column located above the said feed level and the production of a secondary reflux stream from the said top condenser refluxed to the top of the recovery column.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: December 2, 2008
    Assignee: Technip France
    Inventor: Henri Paradowski
  • Patent number: 7249469
    Abstract: This invention relates to a method for separating a stream having benzene, toluene and alkyl benzene, said method comprising: feeding the stream into a first distillation column, wherein the stream comprises between about 60 mole percent to about 85 mole percent toluene, between about seven mole percent to about 20 mole percent benzene, and between about seven mole percent to about 20 mole percent alkyl benzene; separating the steam into a first mixture stream and a second mixture stream; feeding the first mixture stream and the second mixture stream into a distillation system; separating the first mixture stream and the second mixture stream into a first product stream, a system recycle stream, and a second product stream.
    Type: Grant
    Filed: November 18, 2004
    Date of Patent: July 31, 2007
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventor: John Roger Porter
  • Patent number: 6907752
    Abstract: A process for the recovery of natural gas liquids (NGL) (ethane, ethylene, propane, propylene and heavier hydrocarbons) from liquefied natural gas (LNG) is disclosed. The LNG feed stream is split with at least one portion used as an external reflux, without prior treatment, to improve the separation and recovery of the natural gas liquids (NGL).
    Type: Grant
    Filed: July 7, 2003
    Date of Patent: June 21, 2005
    Assignee: Howe-Baker Engineers, Ltd.
    Inventors: Scott Schroeder, Kenneth Reddick
  • Patent number: 6837071
    Abstract: Nitrogen is rejected from a feed gas stream comprising methane and nitrogen so as to form a methane product. The feed gas is separated in a double rectification column comprising a higher pressure rectification column 14, a lower pressure rectification column 16, and a condenser-reboiler 18. Product methane is withdrawn from the column 16 by a pump 42 and is vaporised. A flow of gas is recycled from the column 16 to the column 14, being warmed in main heat exchanger 4. A first part of the warmed recycle gas being compressed in compressor 48 to a first pressure and introduced into the higher pressure rectification column 14. A second part of the warmed recycle gas is compressed in the compressor 48 and condensed in a second condenser-reboiler associated with an intermediate main exchange region of the lower pressure column 16 and is returned to the higher pressure rectification column 14.
    Type: Grant
    Filed: July 1, 2003
    Date of Patent: January 4, 2005
    Assignee: The BOC Group plc
    Inventor: John Douglas Oakey
  • Publication number: 20040250569
    Abstract: A gas processing plant has a de-ethanizer and a refluxed absorber, wherein the absorber operates at higher pressure than the de-ethanizer, and wherein at least a portion of the absorber bottoms product is expanded to provide cooling for the absorber reflux stream and/or the distillation column feed stream. Especially contemplated gas processing plants include propane and ethane recovery plants, and where the gas processing plant is an ethane recovery plant, it is contemplated that the ethane product comprises no more than 500 ppm carbon dioxide.
    Type: Application
    Filed: April 15, 2004
    Publication date: December 16, 2004
    Inventor: John Mak
  • Patent number: 6758060
    Abstract: Substantially all the nitrogen is removed from natural gas during the production of LNG, without producing mixed nitrogen/methane streams needing recycle and further processing, or requiring compression for burning as fuel, by operating both the high pressure and the low pressure multistage distillation towers of a two column cryogenic nitrogen rejection unit to produce acceptable liquefied natural gas as tower bottom products, while the low pressure tower is further operated to produce as an overhead a gas steam containing no more than about 1% methane for safe venting to the atmosphere.
    Type: Grant
    Filed: February 14, 2003
    Date of Patent: July 6, 2004
    Assignee: Chart Inc.
    Inventor: John V. O'Brien
  • Patent number: 6755965
    Abstract: A process for ethane extraction from a gas stream based on turboexpansion and fractionation with no mechanical refrigeration is provided. The feed gas is sweetened and dehydrated by a conventional amine process and by a molecular sieve unit, to remove carbon dioxide and water. After this pretreatment, the feed gas undergoes to a series of cooling steps through a cryogenic brazed aluminum heat exchanger and fed to a demethanizer column. A stream rich in methane is recovered from the top of this column and fed to a centrifugal compressor and subsequently routed to a booster/turboexpander. The temperature of the methane gas is greatly reduced by the expansion allowing the cooled methane stream to be a cooling source for cryogenic heat exchanger. Feed for a de-ethanizer column comes from the bottom liquids of the de-methanizer column. Ethane is recovered overhead at the de-ethanizer column.
    Type: Grant
    Filed: April 20, 2001
    Date of Patent: June 29, 2004
    Assignee: Inelectra S.A.
    Inventors: Filippo Pironti, Jorge Vincentelli
  • Patent number: 6601406
    Abstract: Methods and configurations for improved propane recovery plant employ an absorber column, and a deethanizer column with an overhead condenser that produces a reflux condensate. The reflux condensate is recycled to both the absorber column and the deethanizer column, and a third recycling loop feeds propane from the absorber column into the deethanizer column in a gaseous form. The overhead condenser employs cold reject gas from the absorber and/or propane as a refrigerant, and preferred deethanizer columns include an integral water removal contactor.
    Type: Grant
    Filed: June 19, 2002
    Date of Patent: August 5, 2003
    Assignee: Fluor Corporation
    Inventors: Eh Deng, John Mak, Richard B. Nielsen
  • Patent number: 6581410
    Abstract: The invention provides a process for the separation of a heavier hydrocarbon fraction from a gaseous feed comprising a mixture of hydrocarbons, which process comprises subjecting the feed to a first fractionation to form a condensed product; subjecting the condensed product to a second fractionation, at a lower pressure than the first fractionation pressure, to provide the heavier hydrocarbon fraction and distillate fraction; and withdrawing the produced heavier fraction wherein the distillate from the second fractionation is partially condensed to provide reflux streams for both the first and second fractionations. Running the second fractionation at a lower pressure than the first means that there is phased let-down of pressure in two stages, leading to an increased pressure at the suction of the residue gas compressor and reduces power consumption.
    Type: Grant
    Filed: September 4, 2001
    Date of Patent: June 24, 2003
    Assignee: Costain Oil Gas & Process Limited
    Inventors: Grant L. Johnson, Adrian J. Finn, Terence R. Tomlinson
  • Patent number: 6516631
    Abstract: A cryogenic natural gas liquids recovery process which includes the use of a demethanizer and a deethanizer includes a step of recycling a portion of the deethanizer overhead to the demethanizer.
    Type: Grant
    Filed: August 10, 2001
    Date of Patent: February 11, 2003
    Inventor: Mark A. Trebble
  • Patent number: 6405561
    Abstract: A process for separating a feed gas stream containing methane, C2 components, C3 components, and heavier components into a volatile gas stream containing a major portion of the methane and C2 components and a less volatile stream containing a major portion of the C3 and heavier components by adjusting the temperature and pressure of the feed gas stream and charging it to a separator/absorber where the gas stream is separated into a first gas stream containing a major portion of the methane and C2 components with a minor content of C3 and heavier components and a first liquid stream containing a major portion of the C3 and heavier components with a lesser concentration of C2 and lighter components with the first liquid stream being fractionated in a deethanizer into an overhead stream and a bottoms stream with the bottoms stream containing primarily C3 and heavier components with the overhead stream containing primarily C2 and lighter components being at least partially condensed and separated into a liquid re
    Type: Grant
    Filed: June 6, 2001
    Date of Patent: June 18, 2002
    Assignee: Black & Veatch Pritchard, Inc.
    Inventors: Robert A. Mortko, Kevin L. Currence
  • Patent number: 6347533
    Abstract: A fully thermally coupled distillation structure designed to overcome hydraulic limitations in the past has been revealed for separating a multi-component feed stream into three product streams. The fractionation apparatus is equipped with at least one condenser and one reboiler to provide fractionation efficiency surpassing the PETLYUK system. Further, the fractionation apparatus includes innovative designs to enable hydraulically balanced and energy efficient operation at various feed rates, compositions and product specifications.
    Type: Grant
    Filed: March 4, 2000
    Date of Patent: February 19, 2002
    Inventor: Peter Tung
  • Patent number: 6286335
    Abstract: An efficient and easier to operate distillation process separates mixtures containing three of more components into streams enriched in one of the components. The invention converts a two-way communication between two distillation columns of a prior art thermally coupled distillation system into a one-way communication. Either a distillation section is added to one of the two distillation columns or a new distillation column is added, and only a liquid stream is transferred from one distillation column to another distillation column thereby eliminating the implementation of the return vapor stream between the same locations of the two columns. More than one distillation column produces product streams of at least one of the most volatile or the least volatile major constituent components.
    Type: Grant
    Filed: September 3, 1999
    Date of Patent: September 11, 2001
    Assignee: Air Products and Chemicals, Inc.
    Inventor: Rakesh Agrawal
  • Patent number: 6269657
    Abstract: Hydrogen and carbon monoxide are separated from a condensate-containing gaseous mixture thereof by using (a) a “first” stripping column (8) to remove the hydrogen content of the CO-loaded methane stream (6) obtained by washing CO from the gaseous mixture, or the vapor portion from a phase separation thereof, ascending a methane wash column (2) and (b) a “second” stripping column or a flash separator (30) to remove the hydrogen content of the feed gas condensate (9) obtained from the methane wash column (2), or the phase separation. The vapor stream (32) from the second stripping column or flash separator (30) is fed to the first stripping column (8). The liquid stream from the first stripping column and the liquid stream (33) from the second stripping column or flash separator (30) are fed (16, 17, 19 & 20; 34 to 39) to different locations of a separation column (18) providing a gaseous carbon monoxide product stream (21) and a liquid methane wash recycle stream (3).
    Type: Grant
    Filed: June 2, 2000
    Date of Patent: August 7, 2001
    Assignee: Air Products and Chemicals, Inc.
    Inventor: Brian Alfred McNeil
  • Patent number: 6125653
    Abstract: The present invention comprises a process for producing liquefied natural gas from the methane that is produced during natural gas liquids extraction. The process includes distilling the feed to extract methane, then cooling and expanding the methane to produce liquefied natural gas and cold methane vapor. The cold methane vapor is employed as a coolant to precool the feed and to cool the methane before expansion, and is then recompressed for reinjection into the well formation. The bottoms from the methane distillation may be further distilled to extract ethane, which may be cooled with the cold methane vapor and combined with the liquefied natural gas product. A portion of the recompressed methane may be diverted from the compressor train, cooled and expanded to produce additional liquefied natural gas and cold methane vapor.
    Type: Grant
    Filed: April 26, 1999
    Date of Patent: October 3, 2000
    Assignee: Texaco Inc.
    Inventors: Steven W. Shu, Francis A. Christiano, II
  • Patent number: 6116050
    Abstract: The present invention is directed to methods for separating and recovering propane, propylene and heavier hydrocarbons, i.e., the C.sub.3 + hydrocarbons, from a gas feed, e.g., raw natural gas or a refinery or petroleum plant gas stream. These methods employ sequentially configured first and second distillation columns, e.g., a de-methanizer tower followed by a de-ethanizer tower. A cooled gas feed condensate is separated in the first column into methane and a liquid phase comprising ethane and heavier hydrocarbons. The liquid phase is separated in the second column into a gas phase primarily comprising ethane and a second liquid phase primarily comprising the desired C.sub.3+ hydrocarbons. At least a portion of the second gas phase is introduced into the first distillation column as an overhead reflux to improve the separation of C.sub.3+ hydrocarbons. The methods of the present invention permit separation and recovery of more than about 99% of the C.sub.
    Type: Grant
    Filed: December 4, 1998
    Date of Patent: September 12, 2000
    Assignee: IPSI LLC
    Inventors: Jame Yao, Jong Juh Chen, Rong-Jwyn Lee, Douglas G. Elliot
  • Patent number: 6106674
    Abstract: The present invention teaches an efficient and easier to operate distillation system to separate mixtures containing three or more components into streams enriched in one of the components. In this invention, a liquid stream enriched in the least volatile component is withdrawn from the bottom of one distillation column while a vapor stream enriched in the most volatile component is withdrawn from the top of another distillation column. Of these two distillation columns, the pressure of the distillation column with the bottom liquid enriched in the least volatile component is higher; and this higher pressure distillation column transfers at least two vapor streams from different locations to either one or more other distillation columns within the distillation system. For a ternary mixture, both the vapor streams are transferred to the distillation column with the top vapor enriched in the most volatile component.
    Type: Grant
    Filed: May 26, 1998
    Date of Patent: August 22, 2000
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Rakesh Agrawal, Zbigniew Tadeusz Fidkowski
  • Patent number: 6082134
    Abstract: Hydrogen (4), and carbon monoxide (21) are separated from a gaseous mixture thereof, typically a mixture of essentially hydrogen, carbon monoxide and methane (1) using liquid methane (3) to dissolve carbon monoxide in a methane wash column (2), removing (8) residual hydrogen (15) from the loaded methane wash (6,9), and separating (18) the residual loaded methane into carbon monoxide and methane fractions (21,22). The residual hydrogen (15) is removed in a hydrogen stripping column (8), said column being refluxed with a methane rich scrubbing liquid stream (13) withdrawn from an intermediate location of the methane wash column (2).
    Type: Grant
    Filed: July 22, 1998
    Date of Patent: July 4, 2000
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Brian Alfred McNeil, Alan Geoffrey Truscott
  • Patent number: 6021647
    Abstract: Disclosed are methods of and means for producing ethylene by chilling the ethylene plant demethanizer heat exchange train with a refrigerated stream or streams from a cryogenic natural gas plant effective to provide ethylene level refrigeration, by condensing the ethylene distillation tower overhead with ethylene level refrigeration stream or streams from the cryogenic natural gas plant, by refluxing the ethylene plant demethanizer distillation column with a predominantly liquid methane mixture from the cryogenic natural gas plant, and by combinations thereof. Significant advantages in capital and operating costs associated with ethylene production.
    Type: Grant
    Filed: May 22, 1998
    Date of Patent: February 8, 2000
    Assignees: Greg E. Ameringer, Nasar Ullah Nasar, Lonnie Zack Mallory, George M. Hood
    Inventors: Greg E. Ameringer, Nasar Ullah Nasar
  • Patent number: 5956971
    Abstract: This invention relates to a process for producing pressurized liquid rich in methane from a multi-component feed stream containing methane and a freezable component having a relative volatility less than that of methane. The multi-component feed stream is introduced into a separation system having a freezing section operating at a pressure above about 1,380 kPa (200 psia) and under solids forming conditions for the freezable component and a distillation section positioned below the freezing section. The separation system produces a vapor stream rich in methane and a liquid stream rich in the freezable component. At least a portion of the vapor stream is cooled to produce a liquefied stream rich in methane having a temperature above about -112.degree. C. (-170.degree. F.) and a pressure sufficient for the liquid product to be at or below its bubble point. A first portion of the liquefied stream is returned to the separation system to provide refrigeration to the separation system.
    Type: Grant
    Filed: June 26, 1998
    Date of Patent: September 28, 1999
    Assignee: Exxon Production Research Company
    Inventors: Eric T. Cole, Eugene R. Thomas, Ronald R. Bowen
  • Patent number: 5918481
    Abstract: The invention provides a method for separating fluorocarbons from mixtures of fluorocarbon and hydrogen fluoride. In particular, the invention provides a method for separating fluorocarbons, such as pentafluoropropane, from azeotropic mixtures of the fluorocarbon and hydrogen fluoride using compositional variations with pressure.
    Type: Grant
    Filed: November 20, 1997
    Date of Patent: July 6, 1999
    Assignee: AlliedSignal Inc.
    Inventors: Hang Thanh Pham, Rajiv Ratna Singh, Hsueh Sung Tung, Daniel Christopher Merkel, David Goldschmidt, Tadeusz Piotr Rygas
  • Patent number: 5806339
    Abstract: The present invention is an enhancement of the prior art use of partial effects and component distribution regarding NGL fractionation, especially relating to the separation of propane, isobutane, normal butane and gasoline components. The present invention distributes butanes in two separate columns and integrates the thermodynamic efficiency obtained with partial effects to cascade reboiling duty through as many as four separate columns. The resulting savings in energy are compared with the prior art process of sequential fractionation of NGL.
    Type: Grant
    Filed: April 5, 1996
    Date of Patent: September 15, 1998
    Inventor: David B. Manley
  • Patent number: 5791161
    Abstract: The present invention is a set of improvements in deethanizing and depropanizing fractionation steps in NGL processing. The several embodiments of the present invention apply component distribution to multiple columns, interreboiling, intercondensing, thermal coupling and "thermo-mechanical" coupling to the commonly practiced deethanizer/depropanizer fractionation sequence of NGL processing. Also included are methods of capacity expansion or efficiency improvement for existing high pressure NGL deethanization operations.
    Type: Grant
    Filed: June 12, 1997
    Date of Patent: August 11, 1998
    Inventor: David B. Manley
  • Patent number: 5779863
    Abstract: Provided is a novel method and system for separating and purifying perfluorocompounds (PFCs). The method comprises the steps of: (a) introducing a perfluorocompound-containing gas stream into a first distillation column; (b) removing a light product from the first column, and removing a heavy product from the first column; (c) introducing the first column light product into a second distillation column; (d) removing a light product from the second column, and removing a heavy product from the second column; (e) introducing the second column light product into a third distillation column; and (f) removing a light product from the third column, and removing a heavy product from the third column. The method and system can be advantageously used in the treatment of exhaust gases from semiconductor processing tools, and results in highly purified PFCs which can be recycled, thereby avoiding the release of PFCs into the atmosphere.
    Type: Grant
    Filed: January 16, 1997
    Date of Patent: July 14, 1998
    Assignees: Air Liquide America Corporation, Air Liquide Process and Construction
    Inventors: Bao Ha, Timothy Arcuri
  • Patent number: 5685171
    Abstract: A method of separating from gaseous media, such as air or technical gases, organic vapors by substantially isothermally raising the pressure of the media and subjecting them to cooling in a cold scrubber receiving its operating low temperature from circulating first and second flows of refrigerants of moderate and significant refrigeration parameters and provided by resulting condensates.
    Type: Grant
    Filed: March 4, 1996
    Date of Patent: November 11, 1997
    Inventor: Hans Foerster
  • Patent number: 5673571
    Abstract: The present invention is a set of improvements in deethanizing and depropanizing fractionation steps in NGL processing. The several embodiments of the present invention apply component distribution to multiple columns, interreboiling, intercondensing, thermal coupling and "thermo-mechanical" coupling to the commonly practiced deethanizer/depropanizer fractionation sequence of NGL processing.
    Type: Grant
    Filed: March 6, 1996
    Date of Patent: October 7, 1997
    Inventor: David B. Manley