With Added Gas Or Vapor Patents (Class 208/362)
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Patent number: 8524972Abstract: This disclosure relates generally to low temperature steam stripping methods for byproduct polymer and solvent separation from an ethylene oligomerization process. The methods disclosed have been found to separate byproduct polymer from solvent without fouling process equipment or causing other process problems. The byproduct polymer ends up as flowable solid particles in a water stream that may be easily discharged from the process, while solvent is recovered for recycle to the process. In embodiments of the invention, over 90 wt % of the solvent used is recovered and the discharged byproduct polymer is less than 20 wt % solvent.Type: GrantFiled: April 18, 2012Date of Patent: September 3, 2013Assignee: ExxonMobil Chemical Patents Inc.Inventors: Michael W. Weber, Randy L. Foster, James R. Lattner, Jimmy L. Tardy, Michael J. Veraa
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Patent number: 8394264Abstract: In order to keep diesel or heating oil obtained by fractional distillation, in particular after depolymerization of residues, or pyrolysis oil that was obtained by pyrolysis of rubber or organic substances, permanently clear and light, first, the process of discoloration (darkening) is allowed and then a second distillation is carried out, through which a permanently clear and light heating, diesel or heavy oil is obtained.Type: GrantFiled: July 7, 2008Date of Patent: March 12, 2013Inventors: Manfred Sappok, Dieter Wagels
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Patent number: 8303803Abstract: In one aspect, the inventive process comprises a process for pyrolyzing a hydrocarbon feedstock containing nonvolatiles in a regenerative pyrolysis reactor system. The inventive process comprises: (a) heating the nonvolatile-containing hydrocarbon feedstock upstream of a regenerative pyrolysis reactor system to a temperature sufficient to form a vapor phase that is essentially free of nonvolatiles and a liquid phase containing the nonvolatiles; (b) separating said vapor phase from said liquid phase; (c) feeding the separated vapor phase to the pyrolysis reactor system; and (d) converting the separated vapor phase in said pyrolysis reactor system to form a pyrolysis product.Type: GrantFiled: January 13, 2012Date of Patent: November 6, 2012Assignee: ExxonMobil Chemical Patents Inc.Inventors: Paul F. Keusenkothen, James N. McCoy, Frank Hershkowitz
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Patent number: 8142648Abstract: Controlled RVP C5+ products are produced from feed gas in configurations and methods in which a heavier portion of the feed gas is fractionated into several streams having distinct RVP and in which a C5+ stream is produced from the lighter portion of the feed gas. The so formed streams are then combined to produce C5+ products with controlled RVP. Thus, RVP control is achieved without the need for external products for blending process streams derived from the feed gas.Type: GrantFiled: October 24, 2007Date of Patent: March 27, 2012Assignee: Fluor Technologies CorporationInventor: John Mak
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Patent number: 7993435Abstract: A process for cracking hydrocarbon feedstock containing resid comprising: heating the feedstock, mixing the heated feedstock with a fluid and/or a primary dilution steam stream to form a mixture, flashing the mixture to form a vapor phase and a liquid phase which collect as bottoms and removing the liquid phase, separating and cracking the vapor phase, and cooling the product effluent, wherein the bottoms are maintained under conditions to effect at least partial visbreaking. The visbroken bottoms may be steam stripped to recover the visbroken molecules while avoiding entrainment of the bottoms liquid. An apparatus for carrying out the process is also provided.Type: GrantFiled: September 15, 2006Date of Patent: August 9, 2011Assignee: ExxonMobil Chemical Patents Inc.Inventors: Richard C. Stell, George J. Balinsky, James N. McCoy, Paul F. Keusenkothen
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Patent number: 7914667Abstract: In one aspect, the inventive process comprises a process for pyrolyzing a hydrocarbon feedstock containing nonvolatiles in a regenerative pyrolysis reactor system. The inventive process comprises: (a) heating the nonvolatile-containing hydrocarbon feedstock upstream of a regenerative pyrolysis reactor system to a temperature sufficient to form a vapor phase that is essentially free of nonvolatiles and a liquid phase containing the nonvolatiles; (b) separating said vapor phase from said liquid phase; (c) feeding the separated vapor phase to the pyrolysis reactor system; and (d) converting the separated vapor phase in said pyrolysis reactor system to form a pyrolysis product.Type: GrantFiled: May 13, 2008Date of Patent: March 29, 2011Assignee: ExxonMobil Chemical Patents Inc.Inventors: Paul F. Keusenkothen, James N. McCoy, Judith Hey, legal representative, Frank Hershkowitz
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Patent number: 7670573Abstract: A process for decoking of a process that cracks hydrocarbon feedstock containing resid and coke precursors, wherein steam is added to the feedstock to form a mixture which is thereafter separated into a vapor phase and a liquid phase by flashing in a flash/separation vessel, separating and cracking the vapor phase, and recovering cracked product. Coking of internal surfaces in and proximally downstream of the vessel is controlled by interrupting the feed flow, purging the vessel with steam, introducing an air/steam mixture to at least partially combust the coke, and resuming the feed flow when sufficient coke has been removed. An apparatus for carrying out the process is also provided.Type: GrantFiled: October 16, 2006Date of Patent: March 2, 2010Assignee: ExxonMobil Chemical Patents Inc.Inventors: Richard C. Stell, Arthur R. Di Nicolantonio, James M. Frye, Subramanian Annamalai, Nicholas G. Vidonic
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Patent number: 7641870Abstract: Hydrocarbon feedstock containing resid is cracked by a process comprising: (a) heating the hydrocarbon feedstock; (b) mixing the heated hydrocarbon feedstock with steam and optionally water to form a mixture stream; (c) introducing the mixture stream to a flash/separation apparatus to form i) a vapor phase at its dew point which partially cracks and loses/or heat causing a temperature decrease and partial condensation of the vapor phase in the absence of added heat to provide coke precursors existing as uncoalesced condensate, and ii) a liquid phase; (d) removing the vapor phase as overhead and the liquid phase as bottoms from the flash/separation apparatus; (e) treating the overhead by contacting with a hydrocarbon-containing nucleating liquid substantially free of resid and comprising components boiling at a temperature of at least about 260° C. (500° F.Type: GrantFiled: January 25, 2008Date of Patent: January 5, 2010Assignee: ExxonMobil Chemical Patents Inc.Inventors: Richard C. Stell, Nicholas G. Vidonic
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Publication number: 20090008296Abstract: In order to keep diesel or heating oil obtained by fractional distillation, in particular after depolymerization of residues, or pyrolysis oil that was obtained by pyrolysis of rubber or organic substances, permanently clear and light, first, the process of discoloration (darkening) is allowed and then a second distillation is carried out, through which a permanently clear and light heating, diesel or heavy oil is obtained.Type: ApplicationFiled: July 7, 2008Publication date: January 8, 2009Applicant: CLYVIA TECHNOLOGY GMBHInventors: Manfred Sappok, Dieter Wagels
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Patent number: 7060865Abstract: Disclosed is a process for removing DME from a stream containing C4 olefins. The process includes providing a first stream comprising C4 olefins, C5+ hydrocarbons, DME, and methanol. The first stream is separated into a second stream comprising the C4 olefins and the DME and a third stream comprising the C5+ hydrocarbons and the methanol. The second stream is directed to a DME absorption unit, wherein the second stream contacts water under conditions effective to separate the C4 olefins from the DME. Also disclosed is a process including contacting the first stream with water in a methanol removal unit under conditions effective to separate remove the methanol therefrom; distilling the methanol-depleted stream to remove C5+ hydrocarbon components, and contacting the stream with water in a DME removal unit under conditions effective to form an overhead stream comprising the C4 olefins and a bottoms stream comprising the DME.Type: GrantFiled: November 12, 2002Date of Patent: June 13, 2006Assignee: ExxonMobil Chemical Patents Inc.Inventors: Zhong Yi Ding, James Richardson Lattner
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Patent number: 6855244Abstract: In an embodiment, the invention relates to a method for reducing coke agglomeration in petroleum streams derived from coking processes. In a preferred embodiment, the invention relates to a method for mitigating filter fouling from a coker gas oil by using a pusher gas substantially free of molecular oxygen.Type: GrantFiled: July 10, 2002Date of Patent: February 15, 2005Assignee: ExxonMobil Research and Engineering CompanyInventors: Michael Siskin, Simon R. Kelemen
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Patent number: 6830677Abstract: In an embodiment, the invention relates to a method for reducing coke agglomeration in petroleum streams derived from coking processes. In a preferred embodiment, the invention relates to a method for mitigating filter fouling from a coker gas oil wherein an oxygen scavenger is employed to remove molecular oxygen and peroxides.Type: GrantFiled: July 10, 2002Date of Patent: December 14, 2004Assignee: ExxonMobil Research and Engineering CompanyInventors: Michael Siskin, Simon R. Kelemen
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Patent number: 6746567Abstract: A film or tape has one of its major surfaces defined by microstructured features including a plurality of channels defined by spaced apart protrusions. The microstructured film is able to acquire liquids and to control the directional transport of such liquids for subsequent removal therefrom. The transport can be passive or active (i.e., caused or enhanced by an applied potential). The inventive microstructured films and tapes have applications in laminate floor assemblies (for spill removal) and industrial articles such as computer keyboards and other devices and assemblies that benefit from fluid removal. The invention also has application in evaporative and condensation applications. In one embodiment, at least one cross-channel is formed on the microstructured surface to join adjacent channels for liquid flow therebetween.Type: GrantFiled: December 20, 2002Date of Patent: June 8, 2004Assignee: 3M Innovative Properties CompanyInventors: Raymond P. Johnston, Sara B. Mortenson, Douglas A. Huntley, Stephanie B. Castiglione
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Patent number: 6413414Abstract: Methods and apparatus to separate a light lube stock product and a heavy lube stock product from heavy dewaxed lube oils are described which maintain product specifications while utilizing conventional refinery equipment. The heavy dewaxed lube oil stream is first heated, such as in a spiral heat exchanger in the top of a vacuum stripper, with the heavy lube stock fraction, and/or with hot oil. Next, the heated heavy dewaxed lube oil stream is injected into the vacuum stripper, and fuel gas is injected at the bottom of the stripper as the stripping medium. A light lube stock fraction is removed from the upper portion of the stripper, and a heavy lube stock fraction is removed from the lower portion thereof. Optionally, the gas stripping medium is removed from the top of the stripper by a vacuum pump and used to fuel a hot oil exchanger to heat the oil which in turn is employed to heat the heavy dewaxed lube oil stream.Type: GrantFiled: May 4, 2000Date of Patent: July 2, 2002Assignee: Bechtel CorporationInventors: Victor E. Arnold, Richard T. Cleveland
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Patent number: 6348137Abstract: An apparatus and a method for separating a liquid mixture by fractional distillation. The apparatus includes at least two chambers with a conduit from the lower portion of a chamber which contains liquid to the upper portion of an adjacent chamber, a source of pressurized vapor, and a conduit from the source of pressurized vapor to the lower portion of the chamber which contains liquid. Flow of the liquid from the chamber which contains liquid is effected by introducing pressurized vapor into the liquid, thereby reducing the density of the liquid, pumping the liquid into the upper portion of the adjacent chamber. The two or more chambers can be housed in a single circular vessel, where the chambers are separated by partitions radiating from the center of the cylindrical vessel to the wall of the vessel. The apparatus can have a reduced height compared to conventional distillation columns.Type: GrantFiled: January 7, 2000Date of Patent: February 19, 2002Assignee: IOR Energy Pty Ltd.Inventor: Arthur Nommensen
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Patent number: 6030524Abstract: In an atmospheric pipestill stripping process where steam is utilized as the stripping gas to strip bottoms and side stream products, the improvement comprising utilizing methanol or a methanol and steam mixture as said stripping gas. In a refinery atmospheric pipestill stripping process utilizing a stripping gas, said process comprising utilizing a gas selected from the group consisting of methanol and a mixture of methanol and steam as said stripping gas.Type: GrantFiled: October 6, 1998Date of Patent: February 29, 2000Assignee: Exxon Research and Engineering CoInventors: David W. Savage, Guido Sartori
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Patent number: 5916432Abstract: A transition metal salt, preferably ammonium heptamolybdate, is dissolved in water to provide a solution containing the dispersed catalyst precursor. The solution is atomized by passing it through an atomizing nozzle submerged in hot oil. The minute atomized droplets are delivered into the hot oil and the water is flashed to form steam bubbles. The precursor forms catalytic particles distributed in the oil.Type: GrantFiled: September 24, 1997Date of Patent: June 29, 1999Assignee: Alberta Oil Sands Technology and Research AuthorityInventors: Richard Anthony McFarlane, Ted Cyr, Randall Wayne Tedford Hawkins
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Patent number: 5352336Abstract: Water and organic low-boiling constituents in organic heat transfer fluids used to heat commercial processes are removed by introducing a gas such as nitrogen into a turbulent flow of the heat transfer fluid and separating gas which then contains low-boiling constituents from the heat transfer fluid of the heat transfer system. The gas containing low-boiling constituents may be sent to a condenser to return heat transfer fluid which also vaporizes into the gas, but to a lesser extent than the low-boilers, to the heat transfer system. The gas containing low-boiling constituents is then combusted.Type: GrantFiled: June 17, 1993Date of Patent: October 4, 1994Assignee: The Dow Chemical CompanyInventors: Walter F. Seifert, Gary R. Buske, John B. Cuthbert
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Patent number: 5256258Abstract: Water and organic low-boiling constituents in a organic heat transfer fluids used to heat commercial processes are removed by counter current stripping the fluid with a gas such as nitrogen. The gas containing low-boiling constituents is sent to a rectification column and condenser to return heat transfer fluid which also vaporizes into the gas, but to a lesser extent than the low-boilers, to the heat transfer system.Type: GrantFiled: November 27, 1991Date of Patent: October 26, 1993Assignee: The Dow Chemical CompanyInventors: Walter F. Seifert, Gary R. Buske, John B. Cuthbert
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Patent number: 5225159Abstract: A method is provided for treating a sewage sludge-derived oil having a particular chemical composition, to reduce its odor. The method includes the first step of distilling the sewage sludge-derived oil to 150.degree. C. to remove water and volatile organic components, and then the essential step of circulating a gas consisting essentially of carbon dioxide gas therethrough.Type: GrantFiled: December 13, 1991Date of Patent: July 6, 1993Inventors: Henry Sawatzky, Terrance Giddings, Brian Farnand
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Patent number: 5141630Abstract: A process for separating or stripping lighter components from a heavier hydrocarbon feedstock contaminated with or otherwise including light components. The separation is accomplished by introducing the feedstock into a column and allowing the feedstock to flow through the column, contacting a first stripping medium and a second stripping medium. The first stripping medium entrains the lighter components. The second stripping medium entrains the first stripping medium and any lighter components remaining in the feedstock. Preferred first stripping media include hydrogen, methane, propane, and other inert gas and preferred second stripping media include nitrogen and other inert gas.Type: GrantFiled: July 19, 1991Date of Patent: August 25, 1992Assignee: Lyondell Petrochemical CompanyInventors: Martin P. Grosboll, Richard B. Halsey
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Patent number: 5105041Abstract: A process for the production of alkylaromatic hydrocarbons uses a working fluid to reduce the costs of separating an unreacted aromatic feed substrate from aromatic hydrocarbon products. Unreacted aromatic substrate is combined with a light hydrocarbon, such as propane, to form a combined effluent stream. The combined effluent stream enters a flash separator where unreacted aromatic substrate is lifted overhead with the light hydrocarbon while heavier aromatic products are recovered below. The aromatic substrate and light hydrocarbon are easily separated in a simple separation zone. Lifting the aromatic substrate with the working fluid reduces the volume of aromatic substrate that remains with the aromatic product so that the more energy intensive separation of the aromatic substrate and aromatic product is performed on a reduced volume of material.Type: GrantFiled: September 10, 1990Date of Patent: April 14, 1992Assignee: UOPInventors: Don L. Ferk, Eugene Schmelzer, Edward C. Haun
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Patent number: 5102531Abstract: A process for treating a hydrocarbonaceous feed stream containing a non-distillable component to produce a distillable hydrocarbonaceous product and a heavy product comprising the non-distillable component while minimizing thermal degradation of the hydrocarbonaceous feed stream which process comprises the steps of: (a) contacting the hydrocarbonaceous feed stream with a hot first hydrogen-rich gaseous stream having a temperature greater than the hydrocarbonaceous feed stream in a flash zone at flash conditions without indirect heat exchange thereby increasing the temperature of the hydrocarbonaceous feed stream and vaporizing at least a portion thereof to provide a hydrocarbonaceous vapor stream comprising hydrogen and a heavy product comprising the non-distillable component; (b) removing the hydrocarbonaceous vapor stream comprising hydrogen from the flash zone without contacting the vapor stream with hydrocarbonaceous liquid; (c) condensing at least a portion of the hydrocarbonaceous vapor stream comprisinType: GrantFiled: October 9, 1990Date of Patent: April 7, 1992Assignee: UOPInventors: Tom N. Kalnes, Robert B. James, Jr.
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Patent number: 5100536Abstract: A method of processing hydrocarbon substances including coal, heavy crude oil, and bitumen by hydrogenating the hydrocarbon substance with a gas containing from 20%-100% hydrogen at a pressure in the range of from 50 bar to 700 bar and at a temperature in the range of from 250.degree. C. to 600.degree. C. to produce a hydrogenation residue which is treated in a secondary stripping operation using hydrogen gas at a pressure between about 1.2 bar and 150 bar to recover light hydrocarbon gases from the hydrogenation residue.Type: GrantFiled: April 30, 1990Date of Patent: March 31, 1992Assignee: Ruhrkohle AGInventors: Ulrich Bonisch, Claus Strecker, Wolfdieter Klein
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Patent number: 5028313Abstract: A process for treating a hydrocarbonaceous feed stream containing a non-distillable component to produce a distillable hydrocarbonaceous product and a heavy product comprising the non-distillable component while minimizing thermal degradation of the hydrocarbonaceous feed stream which process comprises the steps of: (a) contacting the hydrocarbonaceous feed stream with a hot first hydrogen-rich gaseous stream having a temperature greater than the hydrocarbonaceous feed stream in a flash zone at flash conditions without indirect heat exchange thereby increasing the temperature of the hydrocarbonaceous feed stream and vaporizing at least a portion thereof to provide a hydrocarbonaceous vapor stream comprising hydrogen and a heavy product comprising the non-distillable component; (b) removing the hydrocarbonaceous vapor stream comprising hydrogen from the flash zone without contacting the vapor stream with hydrocarbonaceous liquid; (c) condensing at least a portion of the hydrocarbonaceous vapor stream comprisinType: GrantFiled: May 19, 1989Date of Patent: July 2, 1991Assignee: UOPInventors: Tom N. Kalnes, Robert B. James, Jr.
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Patent number: 4906338Abstract: A method for removing the volatile constituents from gasoline and volatile organic chemicals from contaminated potable water when a fluid including gasoline-water mixture and when contaminated potable water is introduced into a vertical tower includes the steps of flowing the gasoline-water fluid and the water downward in a tower over and in contact with media trays stacked in courses in the tower. The media trays, either circular or square, fit closely within the tower inner wall, such trays are aluminum or molded plastic frames one inch by one inch angles one-eighth inch thick, with a plurality of one and one-half inch wide slats one-quarter of an inch thick on the top of the frame; the slats being spaced apart not less than one-half inch nor more than three-quarters of an inch.Type: GrantFiled: October 8, 1987Date of Patent: March 6, 1990Inventor: Walter W. DeLoach
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Patent number: 4885424Abstract: A process for the production of alkylaromatic hydrocarbons uses a light hydrocarbon recycle to reduce the costs of separating an unreacted aromatic feed substrate from aromatic hydrocarbon products. Unreacted aromatic substrate is combined with a light hydrocarbon, such as propane, to form a combined effluent stream. The combined effluent stream enters a flash separator where unreacted aromatic substrate is lifted overhead with the light hydrocarbon while heavier aromatic products are recovered below. The aromatic substrate and light hydrocarbon are easily separated in a simple separation zone. Lifting the aromatic substrate with the light hydrocarbon reduces the volume of aromatic substrate that remains with the aromatic product so that the more energy intensive separation of the aromatic substrate and aromatic product is performed on a reduced volume of material.Type: GrantFiled: February 5, 1988Date of Patent: December 5, 1989Assignee: UOPInventors: Don L. Ferk, Eugene Schmelzer, Edward C. Haun
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Patent number: 4853088Abstract: A process and apparatus for separating volatile components from a volatile-containing liquid by a stripping gas flowing countercurrent to the liquid. Separation of the volatile components is enhanced by heating the liquid with radiant solar energy and agitating the liquid as it flows.Type: GrantFiled: April 12, 1988Date of Patent: August 1, 1989Assignee: Marathon Oil CompanyInventor: David D. Conway
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Patent number: 4822480Abstract: Improved product stripping in a catalytic hydrodesulfurization (CHD) product stream is obtained by employing off-gas from the unit as a stripping medium. The compressed off-gas is introduced into the stripper below the stripper feed level. The stripper may be operated at pressures higher than those previously employed in CHD product strippers and this permits LPG recovery to be maximized with lower product sulfur levels and reduced load in the off-gas compressor.Type: GrantFiled: December 22, 1987Date of Patent: April 18, 1989Assignee: Mobil Oil CorporationInventors: Mohsen N. Harandi, Hartley Owen, Michael T. Siuta
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Patent number: 4565623Abstract: This invention deals with a method for deasphalting heavy oils by mixing the oil with a completely miscible solvent at a low treat ratio and then subjecting the resulting one phase mixture to a gaseous antisolvent, such as carbon dioxide, to separate the mixture into two phases. The upper phase contains the majority of the miscible solvent and the product oil containing a significantly lower CCN then did the feedstock.Type: GrantFiled: August 20, 1984Date of Patent: January 21, 1986Assignee: Exxon Research and Engineering Co.Inventor: Thomas A. Davis
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Patent number: 4536283Abstract: The present invention relates to a process for the recovery of hydrocarbon oils from other heavier oils such as vacuum residua and, more particularly, to an improved process for deasphalting petroleum oils containing those asphalts. In one aspect of the invention, the process treats a solvent which has contacted the heavy oil with a gaseous antisolvent to separate effectively and usually without distillation, the solvent from the extracted oil. The deasphalted oil product typically will have low metals contaminants and enhanced MCR. Utilities or energy requirements for the process may be improved over prior art processes.Type: GrantFiled: August 20, 1984Date of Patent: August 20, 1985Assignee: Exxon Research and Engineering Co.Inventor: Thomas A. Davis
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Patent number: 4465584Abstract: Coal, petroleum residuum and similar carbonaceous feed materials are subjected to hydroconversion in the presence of molecular hydrogen to produce a hydroconversion effluent which is then subjected to one or more separation steps to remove lower molecular weight liquids and produce a heavy bottoms stream containing high molecular weight liquids and unconverted carbonaceous material. The viscosity of the bottoms streams produced in the separation step or steps is prevented from increasing by treating the feed to the separation step or steps with hydrogen sulfide gas prior to or during the separation step or steps. The viscosity of the heavy bottoms stream produced in the final separation step is also controlled by treating these bottoms with hydrogen sulfide gas.Type: GrantFiled: March 14, 1983Date of Patent: August 14, 1984Assignee: Exxon Research & Engineering Co.Inventors: Edward Effron, Alexis A. Giese, Gerald A. Melin
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Patent number: 4457837Abstract: A nonpolluting process for neutralizing corrosive acid components in the overheads of petroleum distillation units is disclosed. In the process, ammonia is added to said units and carried overhead. The overhead is condensed to yield hydrocarbon phase and an ammonia-containing aqueous phase. The aqueous phase is stripped to yield an ammoniacal steam that is returned to the distillation units and a substantially ammonia-free bottoms.Type: GrantFiled: July 23, 1982Date of Patent: July 3, 1984Assignee: Chevron Research CompanyInventor: Robert A. Farnham
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Patent number: 4424117Abstract: Hydrogen partial pressure in the distilled vapor phase in a stripper is maintained sufficienty to allow a smooth distillation processing whereby an efficient crude oil stripping is performed. The distillate overhead thus produced is maintained at a temperature high enough for direct feeding to a subsequent hydrotreating process by means of a reflux cooler installed at the top of the stripper.Type: GrantFiled: May 7, 1982Date of Patent: January 3, 1984Inventor: Masaya Kuno
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Patent number: 4127393Abstract: Apparatus and a process are provided whereby constituents of liquid mixtures eg non-distillate oils are vaporized under non-decomposing conditions in the presence of gases. Liquid components form a stream comprising the gas, vaporized and liquid constituents of the mixture are removed from the stream. Process may be employed to provide a vaporized feedstock for the non-catalytic thermal hydrogenation of hydrocarbon-based materials in the production of methane containing gases wherein the gas used for vaporization is the same as that used for the subsequent hydrogenation steps.Type: GrantFiled: July 25, 1977Date of Patent: November 28, 1978Assignee: British Gas CorporationInventors: Cyril Timmins, Henry L. Conway, Henry J. F. Stroud