Chilling Patents (Class 208/37)
  • Patent number: 7351324
    Abstract: The present invention relates to a liquid fuel blended by dissolving crude pentane into the heavy oil with different proportions, and applied to different combustion system respectively; the fuel thus formed is easily dissolved, volatilized, atomized and vaporized into fine vapor articles, so it will burn completely to not only increase the heat value but also reduce the pollution without producing the dense smoke like common heavy oil combustion furnace. In addition, alkanes with low price, low octane value and high volatility substitute or blend with the crude pentane to become a liquid fuel having suitable initial boiling point, viscosity and fluidity as well as low price and low pollution, which is much better than common diesel oil.
    Type: Grant
    Filed: January 24, 2003
    Date of Patent: April 1, 2008
    Inventor: Hong-Lin Chen
  • Patent number: 6890425
    Abstract: A method of refining a petroleum product to remove aromatics and to separate paraffinic oils and waxes is provided. The method involves the utilization of phase equilibria wherein crystallized or solidified waxes, normally present in the petroleum product, are used to remove oils from a liquid solvent phase containing dissolved aromatics present in the unrefined petroleum product. The wax containing the oils is separated from the aromatic-containing solvent and is further processed to separate the waxes and oils. For petroleum products containing little, if any, wax, additional wax may be added and recycled back for further use in removing oils from the petroleum product. The method has particular application in preparing lubricating oils having a high viscosity index, where the presence of aromatics and wax can be detrimental.
    Type: Grant
    Filed: September 30, 2002
    Date of Patent: May 10, 2005
    Assignee: Process Dynamics, Inc.
    Inventors: Michael D. Ackerson, Michael Steven Byars
  • Patent number: 6497813
    Abstract: A method of refining a petroleum product to remove aromatics and to separate paraffinic oils and waxes is provided. The method involves the utilization of phase equilibria wherein crystallized or solidified waxes, normally present in the petroleum product, are used to remove oils from a liquid solvent phase containing dissolved aromatics present in the unrefined petroleum product. The wax containing the oils is separated from the aromatic-containing solvent and is further processed to separate the waxes and oils. For petroleum products containing little, if any, wax, additional wax may be added and recycled back for further use in removing oils from the petroleum product. The method has particular application in preparing lubricating oils having a high viscosity index, where the presence of aromatics and wax can be detrimental.
    Type: Grant
    Filed: January 19, 2001
    Date of Patent: December 24, 2002
    Assignee: Process Dynamics, Inc.
    Inventors: Michael D. Ackerson, Michael Steven Byars
  • Publication number: 20020096451
    Abstract: A method of refining a petroleum product to remove aromatics and to separate paraffinic oils and waxes is provided. The method involves the utilization of phase equilibria wherein crystallized or solidified waxes, normally present in the petroleum product, are used to remove oils from a liquid solvent phase containing dissolved aromatics present in the unrefined petroleum product. The wax containing the oils is separated from the aromatic-containing solvent and is further processed to separate the waxes and oils. For petroleum products containing little, if any, wax, additional wax may be added and recycled back for further use in removing oils from the petroleum product. The method has particular application in preparing lubricating oils having a high viscosity index, where the presence of aromatics and wax can be detrimental.
    Type: Application
    Filed: January 19, 2001
    Publication date: July 25, 2002
    Inventors: Michael D. Ackerson, Michael Steven Byars
  • Patent number: 6294076
    Abstract: The invention is a process for producing a mixture of Fischer-Tropsch product that is solid at ambient conditions (between 32° F. and 95° F.), such as wax, and hydrocarbon liquid, such as naphtha, that can be pumped at ambient temperature (between 32° F. and 95° F.). The temperature of the mixture is controlled below the melting point of the Fischer-Tropsch product. The present invention provides for the transport of Fischer-Tropsch product from a remote location in a readily available medium, such as naphtha, via pipeline, tanker or railcar. At the completion of the transport, the hydrocarbon liquid and Fischer-Tropsch product are separated by conventional methods such as flashing, distillation, or filtration with minimal contamination from the hydrocarbon liquid.
    Type: Grant
    Filed: April 21, 2000
    Date of Patent: September 25, 2001
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: W. B. Genetti, L. L. Ansell, Daniel F. Ryan, Paul J. Berlowitz
  • Patent number: 6268401
    Abstract: The invention is a process for producing a mixture of wax and crude oil which can be pumped at ambient temperature. The wax is preferably a Fisher-Tropsch wax. The temperature of the crude oil is controlled to a level below the dissolution temperature of the wax. The wax crystals are homogenized and dispersed into the crude oil to form a mixture. The present invention prevents the wax from dissolving in the crude oil and subsequently re-crystallizing at lower temperatures which can substantially increase the viscosity of the mixture thereby decreasing the effectiveness of transporting the mixture.
    Type: Grant
    Filed: April 21, 2000
    Date of Patent: July 31, 2001
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Bruce R. Cook, Eric B. Sirota, Hu Gang, Loren L. Ansell
  • Patent number: 6074548
    Abstract: A process for fractional crystallization of paraffin from mineral oil based and synthetic crude paraffin, wherein crude paraffin having a high oil content is crystallized in a crystallizer equipped with perforated metal sheets (31) extending in a zig-zag in the spaces between the heat exchanger surfaces (39). The paraffin-containing melt is only solidified to an extent such that the fractions and oils for discharge remain liquid and are run off without total solidification of the melt. The perforated sheets (31) support the layers of crystals (43) and during sweating the paraffin is detached in strips from the heat exchanger surface (39) and is adapted to rest on the sloping perforated sheets (31). The inclination of the perforated sheets (31) guides and moves the paraffin strips (53), so that the paraffin strips remain in contact with the heat exchanger surfaces (39) while being pressed by their own weight along the inclined surface (30) towards the heat exchanger surfaces (39).
    Type: Grant
    Filed: July 16, 1998
    Date of Patent: June 13, 2000
    Assignees: Schumann Sasol GmbH & Co. KG, Sulzer Chemtech AG
    Inventors: Norbert Matzat, Gunther Hildebrand, Ferdinand Richter, Manfred Stepanski, Florian Lippuner, Herbert Engstler, Bernhard J. Jans
  • Patent number: 6042715
    Abstract: A thermodynamic model is formed which allows determination of the temperature at which waxes or paraffins appear in petroleum fluids, and notably in crudes, as well as the solid fraction that precipitates when the temperature of the petroleum fluid falls below this critical value. A differentiation is established between n-paraffins, iso-paraffins, naphthenes and aromatics. The model utilizes an analytical representation of the fluids by pseudo-components, the physico-chemical parameters of most of them being determined by combination of the corresponding parameters of a certain number of pure hydrocarbons gathered in a database. The model takes account of the non-ideality of the solid, liquid, and gas phases. Two of the pseudo-constituents including the heaviest fractions are represented by two ficticious molecules, each being defined by a molar distribution among various groups which constitute them, and a group contribution method is used to calculate the thermodynamic properties thereof.
    Type: Grant
    Filed: September 16, 1997
    Date of Patent: March 28, 2000
    Assignee: Institut Francais du Petrole
    Inventors: Sandra Calange, Veronique Ruffier-Meray, Emmanuel Behar
  • Patent number: 5976353
    Abstract: A process for producing a high VI/low volatility lubricating oil basestock. The process comprises subjecting the raffinate from a solvent extraction step to a two step, single stage hydroconversion process wherein the first step involves severe hydroconversion of the raffinate followed by a cold hydrofinishing step.
    Type: Grant
    Filed: June 28, 1996
    Date of Patent: November 2, 1999
    Assignee: Exxon Research and Engineering Co
    Inventors: Ian A. Cody, Douglas R. Boate, Sandra J. Alward, William J. Murphy, John E. Gallagher, Gary L. Harting
  • Patent number: 5935416
    Abstract: A process for producing a high VI/low volatility lubricating oil basestock. The process comprises subjecting the raffinate from a solvent extraction step to a two-step, single-stage hydroconversion process wherein the first step involves severe hydroconversion of the raffinate followed by a cold hydrofinishing step. The effluent from the cold hydrofinishing step is then catalytically dewaxed or in the alternative, solvent dewaxed followed by catalytic dewaxing.
    Type: Grant
    Filed: February 13, 1998
    Date of Patent: August 10, 1999
    Assignee: Exxon Research and Engineering Co.
    Inventors: Ian A. Cody, Douglas R. Boate, William J. Murphy, Daniel P. Leta
  • Patent number: 5827952
    Abstract: Acoustic-wave sensor apparatus and method for analyzing a normally liquid petroleum-based composition for monitoring deposition-point temperature. The apparatus includes at least one acoustic-wave device such as SAW, QCM, FPM, TSM or APM type devices in contact with the petroleum-based composition for sensing or detecting the surface temperature at which deposition occurs and/or rate of deposition as a function of temperature by sensing an accompanying change in frequency, phase shift, damping voltage or damping current of an electrical oscillator to a known calibrated condition. The acoustic wave device is actively cooled to monitor the deposition of constituents such as paraffins by determining the point at which solids from the liquid composition begin to form on the acoustic wave device. The acoustic wave device can be heated to melt or boil off the deposits to reset the monitor and the process can be repeated.
    Type: Grant
    Filed: May 27, 1997
    Date of Patent: October 27, 1998
    Assignee: Sandia National Laboratories
    Inventors: Arthur J. Mansure, James J. Spates, Stephen J. Martin
  • Patent number: 5651877
    Abstract: A semicontinuous process for solvent dewaxing a waxy petroleum oil feed stream including the steps of: diluting of the waxy oil feed stream with solvent; feeding cold oil/solvent/wax mixture to a filter to remove the wax and obtain an oil/solvent filtrate stream; contacting the oil/solvent filtrate stream with a selective semipermeable membrane to selectively transfer solvent through the membrane to obtain a solvent-rich permeate; and periodically directing a warm stream of recovered solvent onto the membrane surface to wash the membrane and remove impurities therefrom.
    Type: Grant
    Filed: April 16, 1996
    Date of Patent: July 29, 1997
    Assignee: Mobil Oil Corporation
    Inventors: Ronald M. Gould, Harold A. Kloczewski, Krishna S. Menon, Thomas E. Sulpizio, Lloyd S. White
  • Patent number: 5547562
    Abstract: The invention decloses a method for dewaxing a hydrocarbon oil which comprises adding an oil-soluble poly C.sub.18 -C.sub.22 alkylmethacrylate having a molecular weight of from about 10,000 to about 2,000,000 daltons to a hydrocarbon oil containing wax; cooling the oil to allow wax crystals to form, separating the wax crystals from the oil and recovering a dewaxed oil.
    Type: Grant
    Filed: May 25, 1995
    Date of Patent: August 20, 1996
    Assignee: Nalco/Exxon Energy Chemicals, L.P.
    Inventors: Rupinder S. Grewal, Michael E. Joyce, Randall F. Nord
  • Patent number: 5494566
    Abstract: A process for solvent dewaxing petroleum feedstock to separate crystallized wax from lubricant oil by filtration of a wax/oil/solvent mixture. The feedstock is sequentially cooled and mixed with cold polar solvent to form a wax crystal phase and oil-solvent phase, and-the oil-solvent filtrate stream is contacted with solvent permeable selective membrane at low temperature to recover an internal circulating permeate solvent stream and an oil-rich retentate stream containing dewaxed oil product and residual solvent. Improved operation is achieved by splitting the internal circulating solvent stream into a multiple cold solvent recycle streams and injecting a plurality of the cold solvent recycle streams into the waxy petroleum feedstock during sequential cooling and mixing. By initially injecting a cold recycle solvent stream in to the waxy petroleum feedstock at a small temperature differential near the wax crystallization temperature, shock cooling and excess small wax crystal formation is avoided.
    Type: Grant
    Filed: May 26, 1994
    Date of Patent: February 27, 1996
    Assignee: Mobil Oil Corporation
    Inventors: Ronald M. Gould, Albert R. Nitsch
  • Patent number: 5400618
    Abstract: Batch auto-refrigerative dewaxing processes employing at least two batch chilling vessels can be improved by integrating the batch auto-refrigerative dewaxing chilling cycles of the chilling vessels so as to have their cycles of operation overlap and use thermocompressors to recover the energy of the hot, high pressure cycle stream of one vessel by operation on the cooler, low pressure cycle stream of the other vessel to increase the pressure of said low pressure cycle stream. The overlap operation of the multiple batch chillers integrated through the thermocompressor will also permit running the cool, low pressure cycle to a pressure even lower than atmospheric without inleakage of air because of the vacuum effect generated by the hot, higher pressure stream running through the thermocompressor. Autorefrigerative dewaxing employs liquified normally gaseous solvents as the chilling solvents such as C.sub.3 -C.sub.4 alkanes/alkenes e.g. propane, propylene, butane, butylene and mixtures thereof.
    Type: Grant
    Filed: October 26, 1993
    Date of Patent: March 28, 1995
    Assignee: Exxon Research & Engineering Co.
    Inventor: Abraham R. DeKraker
  • Patent number: 5401383
    Abstract: The incremental solvent dilution chilling of 600N waxy oils in a staged agitated chilling tower using cold solvent injection is improved in terms of feed filter rate with respect to a 600N waxy oil having a final boiling point of >600.degree. C. and a mean boiling point of about 500.degree. C. when the solvent dewaxing process is practiced under conditions of cold solvent injection such that there is an equal chilling rate/stage profile as compared to an equal temperature drop/stage profile in the chilling tower and with respect to a 600N waxy oil having a final boiling point of 600.degree. C. and a mean boiling point of about 500.degree. C. when the solvent dewaxing process is practiced under conditions of cold solvent injection such that there is an equal temperature drop/stage profile as compared to an equal chilling rate/stage profile in the chilling tower.
    Type: Grant
    Filed: September 10, 1993
    Date of Patent: March 28, 1995
    Assignee: Exxon Research & Engineering Co.
    Inventor: Patrick C. Ewener
  • Patent number: 5360530
    Abstract: A process for solvent dewaxing a waxy oil feed to obtain petroleum oil lubricating stock comprising the steps of contacting a warm waxy oil feed by indirect heat exchange first with cold filtrate, then with refrigerant to crystallize and precipitate the wax in the oil feed to form an oil/solvent/wax mixture. The oil/solvent/wax mixture is diluted with cold solvent to adjust the viscosity of the mixture and the mixture is fed to a filter which filters and removes the wax from the cold oil/solvent/wax mixture. A cold wax cake is recovered and a cold oil/solvent filtrate stream is recovered. The cold oil/solvent filtrate stream is fed, at the filtration temperature, to a selective permeable membrane. The membrane selectively separates the cold filtrate into a cold solvent permeate stream and a cold filtrate stream which contains the dewaxed oil and the remaining solvent. The cold solvent permeate stream at the filtration temperature is recycled to the filter feed stream.
    Type: Grant
    Filed: April 23, 1993
    Date of Patent: November 1, 1994
    Assignee: Mobil Oil Corporation
    Inventors: Ronald M. Gould, William F. Heaney, Albert R. Nitsch, Howard E. Spencer
  • Patent number: 5358625
    Abstract: A process for solvent dewaxing a waxy oil feed to produce a lubricating oil by contacting a warm waxy oil feed in counter-current with a cold oil/solvent filtrate stream through a selectively permeable membrane to transfer cold solvent through the membrane to the feed and simultaneously cool the feed, dilute it with solvent and separate solvent from the cold oil/solvent filtrate stream. The cooled, diluted feed stream is then further cooled to precipitate the wax to form an oil/solvent/wax mixture which is further diluted with cold solvent and filtered to remove wax. The cold oil/solvent filtrate stream is cycled to the selectively permeable membrane for the counter-current contact with the warm waxy oil feed and, after removal of a portion of the solvent over the membrane, is sent to an oil/solvent separation operation in which the solvent is removed from the dewaxed oil.
    Type: Grant
    Filed: April 23, 1993
    Date of Patent: October 25, 1994
    Assignee: Mobile Oil Corporation
    Inventor: Ronald M. Gould
  • Patent number: 5098550
    Abstract: A method for the solvent dewaxing of wax-containing petroleum products with at least one solvent suitable for dewaxing and a polymeric dewaxing aid comprising polyacrylates, by mixing the products to be dewaxed with the solvent and the polymeric dewaxing aid, chilling the mixture so obtained, and separating the precipitated wax, the dewaxing aid used being a mixture of(I) a polymer of esters of acrylic acid with C.sub.10 -C.sub.40 alkanols and(II) a polymer of esters of methacrylic acid with alkanols comprising more than 10 weight percent of branched alkanols,the weight ratio between components (I) and (II) ranging from 1:20 to 20:1.
    Type: Grant
    Filed: October 3, 1990
    Date of Patent: March 24, 1992
    Assignee: Rohm GmbH
    Inventors: Michael Mueller, Horst Pennewiss
  • Patent number: 5006222
    Abstract: An improvement has been discovered in a process for solvent dewaxing a hydrocarbon lubricating oil stock. Solvent dewaxed oils are steam stripped and then vacuum dehydrated at 2.5 psia at the steam stripping temperature of 350.degree. F. to 450.degree. F. Nitrogen or natural gas having a dew point of -100.degree. F. or lower is contacted with the oil at 0.5 to 1 SCF/bbl. A solvent free lubricating oil is produced which is water haze free in cold storage.
    Type: Grant
    Filed: May 23, 1990
    Date of Patent: April 9, 1991
    Assignee: Texaco Inc.
    Inventor: Avilino Sequeira, Jr.
  • Patent number: 4898659
    Abstract: Solvent dewaxing of waxy hydrocarbon oils using scraped surface chillers is improved by injecting cold solvent into the scraped surface chillers at multiple points to augment the indirect chilling occurring in said scraped surface chillers. In utilizing this multi-point cold solvent injecting process it is important to control the .DELTA.T occurring at each injection point within each chiller bank across the entire chiller train.The .DELTA.T at each injection point attributable only to cold solvent injection must be equal if one is to secure the benefit of the present invention which is an improved liquids/solids ratio without deterioration of the feed filter rate.Preferably, to avoid any possible deterioration of filter rate and/or liquids solids, the cold solvent injection should be completed prior to the slurry in the scraped surface chiller train experiences any shock chilling.
    Type: Grant
    Filed: March 21, 1988
    Date of Patent: February 6, 1990
    Assignee: Exxon Research and Engineering Company
    Inventor: Thomas E. Broadhurst
  • Patent number: 4810437
    Abstract: A process for manufacturing a carbon fiber or graphite fiber includes melt-spinning a carbonaceous pitch, infusibilizing the resulting pitch fiber, carbonizing, and when necessary graphitizing the fiber. A precursor of the carbonaceous pitch is centrifuged in a molten state to separate the precursor pitch simultaneously into a solids slurry layer, an optically isotropic phase, and an optically anisotropic phase, and the latter is utilized as the carbonaceous pitch.
    Type: Grant
    Filed: April 21, 1988
    Date of Patent: March 7, 1989
    Assignee: Toa Nenryo Kogyo K.K.
    Inventors: Takayuki Izumi, Kikuji Komine, Wataru Kobayashi
  • Patent number: 4702758
    Abstract: A stream of gas and waxy oil is cooled by an expansion turbine to form a wax/oil slurry, and the slurry is pipeline transported without wax deposition in the pipeline and/or to prevent melting of permafrost along the pipeline right of way.
    Type: Grant
    Filed: May 29, 1986
    Date of Patent: October 27, 1987
    Assignee: Shell Western E&P Inc.
    Inventor: Julia S. Geer
  • Patent number: 4697426
    Abstract: A stream of gas and waxy oil is cooled by a choke to form a wax/oil slurry, and the slurry is pipeline transported without wax deposition in the pipeline and/or to prevent melting of permafrost along the pipeline right of way.
    Type: Grant
    Filed: May 29, 1986
    Date of Patent: October 6, 1987
    Assignee: Shell Western E&P Inc.
    Inventor: William T. Knowles, Jr.
  • Patent number: 4608151
    Abstract: A process for producing high quality, high molecular weight microcrystalline wax from a hydrocracked, undewaxed bright stock, comprising hydrodenitrification, mild hydrofinishing, and solvent dewaxing.
    Type: Grant
    Filed: December 6, 1985
    Date of Patent: August 26, 1986
    Assignee: Chevron Research Company
    Inventor: Stephen J. Miller
  • Patent number: 4461699
    Abstract: In the preparation of a heavy oil with a low Ramsbottom Carbon Test (RCT) from a long residue by a two-stage process comprising catalytic hydrotreatment followed by solvent deasphalting and recycle of the asphalt to the first stage the catalytic hydrotreatment for RCT reduction in the first stage is carried out at such a severity that the C.sub.4.sup.- gas production per percent RCT reduction is kept between defined limits.
    Type: Grant
    Filed: June 24, 1982
    Date of Patent: July 24, 1984
    Assignee: Shell Oil Company
    Inventors: Jacobus Eilers, Willem H. J. Stork
  • Patent number: 4447311
    Abstract: A dewaxing process for reducing the pour point of waxy oils in which the oil is cooled by direct contact with a liquid autorefrigerant such as propane. The wax which separates upon cooling is removed by flotation assisted by the bubbles of vaporized autorefrigerant which rise through the oil to form a frothy slurry of wax which can be decanted and the wax recovered from it. A dewaxing solvent such as methyl ethyl ketone may be used to assist separation of the wax.
    Type: Grant
    Filed: July 22, 1982
    Date of Patent: May 8, 1984
    Assignee: Mobil Oil Corporation
    Inventors: Patrick E. Fowles, Gerald L. Shoemaker, Tsoung-Yuan Yan
  • Patent number: 4441987
    Abstract: An improved process for dewaxing waxy hydrocarbon oils, wherein said waxy oil is cooled in an indirect chilling zone to a temperature greater than the wax separation temperature whereby wax is precipitated to form a wax-oil-solvent slurry, cooling the slurry to the wax separation temperature in an indirect chilling zone thereby precipitating a further portion of wax from said waxy oil and separating said precipitated wax from the wax-oil-solvent slurry in solid-liquid separation means, the improvement comprising using as the indirect chilling zone an indirect heat exchanger means operated at a high level of agitation. Expressed in terms of Impeller Reynolds Number the agitation is on the order of about 1,000 to 1,000,000.Alternatively, the direct chilling zone is totally replaced by the high agitation indirect heat exchanger means.
    Type: Grant
    Filed: March 20, 1981
    Date of Patent: April 10, 1984
    Assignee: Exxon Research & Engineering Company
    Inventor: Thomas E. Broadhurst
  • Patent number: 4334978
    Abstract: In hydrocarbon oil dewaxing processes comprising passing the waxy oil through a staged vertical tower, injecting cold solvent at a plurality of stages along the vertical tower under conditions of high agitation to achieve substantially instantaneous mixing at each point, continuing the chilling, preferably at a rate of from 1.degree. to 8.degree. F. per minute, by means of cold solvent injection until a temperature at least 30.degree. F. above the filtering temperature but less than about 40.degree. to 45.degree. F. above the filtering temperature is reached and completing the cooling of the oil to the separation temperature in rotating element scraped surface chillers, the improvement comprising operating the scraped surface chillers at a chilling temperature range of at least 30.degree. F. while reducing the operating speed of the rotating elements in the scraped surface chiller to a speed of from 5 to 20% preferably 8 to 14% of the original design operation speed.
    Type: Grant
    Filed: November 24, 1980
    Date of Patent: June 15, 1982
    Assignee: Exxon Research & Engineering Co.
    Inventor: Thomas E. Broadhurst
  • Patent number: 4262790
    Abstract: Apparatus for separating paraffin from oil in refineries wherein such separation is accomplished by a cooling process, in a heat exchanger, the apparatus controlling the cooling process by sensing either the pressure upstream of the heat exchanger and directly controlling the flow through a heat exchanger bypass, or sensing the temperature downstream of the heat exchanger and inversely controlling the flow through a heat exchanger bypass, the flow control in each case regulating the flow of cooling liquid through the heat exchanger.
    Type: Grant
    Filed: November 16, 1979
    Date of Patent: April 21, 1981
    Inventor: Alfonso Castiglione
  • Patent number: 4252549
    Abstract: In crystallization units such as wax crystallization units where a scraped surface double pipe heat exchanger type chiller is used, the improvement of replacing the scraped surface chiller tube with a porous tube to provide positive flow of coolant through the tube wall to prevent crystal deposition on the process side of the tube, whereby crystal degradation is eliminated and increased filter rate is obtained.
    Type: Grant
    Filed: May 31, 1979
    Date of Patent: February 24, 1981
    Assignee: Suntech, Inc.
    Inventors: Richard W. Chaunce, Thomas J. McGinley
  • Patent number: 4169039
    Abstract: In a DILCHILL* dewaxing process employing rotary drum wax filters, the waxy slurry in the filters must be periodically dumped and the filters washed with hot solvent to remove wax fines which plug the cloth. The dumped slurry contains useful oil which can be recovered, with no detriment to the subsequent filter rate, by mixing the dumped slurry with the hot filter washings and recycling this mixture back into the DILCHILL dewaxing zone at one or more points therein wherein the temperature of the recycled mixture is from about 5.degree. to 50.degree. F. lower than the bulk temperature of the oil in the dewaxing zone and in an amount ranging from about 0.02 to 0.4 volumes of recycle per volume of feed.* DILCHILL is a registered service mark of the Exxon Research and Engineering Company.
    Type: Grant
    Filed: December 27, 1977
    Date of Patent: September 25, 1979
    Assignee: Exxon Research & Engineering Co.
    Inventor: James D. Bushnell
  • Patent number: 4129583
    Abstract: In a continuous process for separating crystallizable organic components from mixtures thereof in solution, a feedstock of such components is mixed with at least one solvent therefor and the resulting feedstock mixture is continuously fed into a vessel in which a baffle defines a partially confined first zone and a partially confined second zone communicating with the first zone. At least one low-boiling point high-vapor pressure refrigerant is injected into the feedstock mixture in the first zone and evaporates and adiabatically expands therein to effect rapid cooling of the mixture to a selected low temperature and thereby form a slurry of microcrystals of components which are crystallizable down to the selected temperature.
    Type: Grant
    Filed: January 24, 1978
    Date of Patent: December 12, 1978
    Inventor: Klaus Zondek
  • Patent number: 4128472
    Abstract: A solvent dewaxing process for removing wax from intermediate grade waxy petroleum distillate oils wherein a waxy oil stock, prediluted with 0-2 volumes dewaxing solvent is heated to a temperature in the range of about 110 to 130.degree. F for melting all wax therein; wherein the heated waxy oil stock/solvent mixture is cooled to about 5.degree. F above the depressed cloud point and is diluted with 1-5 volumes dewaxing solvent having a temperature 25.degree.-40.degree. F below the depressed cloud point for forming a wax/oil/solvent mixture having a temperature 5.degree.-15.degree. F below the depressed cloud point, and wherein the wax/oil/solvent mixture is further cooled at 1.degree.-8.degree. F/min. to a selected separation temperature in the range of 0 to -40.degree. F for precipitating additional wax. Precipitated wax is removed at the separation temperature to produce a wax free oil/solvent mixture which is subsequently fractionated to yield a dewaxed oil suitable for use in lubricating oils.
    Type: Grant
    Filed: July 5, 1977
    Date of Patent: December 5, 1978
    Assignee: Texaco Inc.
    Inventors: Charles W. Harrison, Paul P. Bozeman, Jr., deceased
  • Patent number: 4115243
    Abstract: A process for dewaxing heavy distillate and residual petroleum oil stocks wherein a waxy oil stock, prediluted with 1-2.5 volumes dewaxing solvent, is cooled to about the depressed cloud point, wherein the cooled, prediluted waxy oil stock is treated with dewaxing solvent, in increments of 0.3-1.5 volumes each to a total dilution of 3.5 to 4 volumes solvent, under conditions of good mixing and cooling at about 1.degree.-8.degree. F/min, to a desired separation temperature for precipitating wax crystals and producing a dewaxed oil.
    Type: Grant
    Filed: July 5, 1977
    Date of Patent: September 19, 1978
    Assignee: Texaco Inc.
    Inventors: Charles W. Harrison, Herbert J. Pitman, Avilino Sequeira
  • Patent number: 4115244
    Abstract: A process for dewaxing a waxy petroleum distillate charge stock, wherein a mixture of waxy oil and solvent, heated for dissolving all solid wax therein, is cooled to a first temperature about 40.degree.-50.degree. F (22.degree. to 28.degree. C) above a selected separation temperature, and is held at such first temperature for a period of 1-2 minutes for equilibrating wax crystallization, wherein said oil-solvent mixture, at said first temperature, is cooled to a second temperature about 15.degree.14 20.degree. F (8.degree.-11.degree. C) above said separation temperature and is held at said second temperature for 1-2 minutes for equilibration of wax crystallization, wherein said oil-solvent mixture, at said second temperature, is cooled to said separation temperature, and wherein solid wax is separated from oil-solvent mixture at said separation temperature.
    Type: Grant
    Filed: July 5, 1977
    Date of Patent: September 19, 1978
    Assignee: Texaco Inc.
    Inventors: Herbert J. Pitman, Charles W. Harrison, Avilino Sequeira
  • Patent number: 4115245
    Abstract: A solvent dewaxing process wherein an intermediate range waxy distillate oil, heated for dissolving all wax therein, is mixed with about 1-4 volumes dewaxing solvent having a temperature in the range of 60.degree.-80.degree. F for forming an oil-solvent mixture having a temperature below depressed cloud point. The oil-solvent mixture is subsequently cooled at 1.degree.-8.degree. F/min to a selected separation temperature for precipitating wax and forming a first wax/oil/solvent mixture. Additional solvent, at about the separation temperature, is mixed with first wax/oil/solvent mixture in an amount equivalent to about 1-2 volumes of waxy oil charge for precipitating additional wax and forming a second wax/oil/sovent mixture. Precipitated wax is separated, at said separation temperature from said second wax/oil/solvent mixture.
    Type: Grant
    Filed: July 5, 1977
    Date of Patent: September 19, 1978
    Assignee: Texaco Inc.
    Inventors: Charles W. Harrison, Leonard R. Watts
  • Patent number: 4115242
    Abstract: A process wherein a light waxy petroleum distillate stock, having a viscosity less than about 200 SUS at 100.degree. F, is heated for melting any wax therein, wherein said heated waxy stock is incrementally mixed with a flowing stream of dewaxing solvent, having a temperature in the range of 40.degree.-80.degree. F, for forming an oil/solvent mixture at a temperature 5.degree.-10.degree. F below the depressed cloud point, and wherein the oil/solvent mixture is cooled at a uniform rate in the range of 1.degree.-8.degree. F/min. to a separation temperature in the range of +25.degree. to -40.degree. F for precipitating wax from said mixture.
    Type: Grant
    Filed: July 5, 1977
    Date of Patent: September 19, 1978
    Assignee: Texaco Inc.
    Inventors: Avilino Sequeira, Herbert J. Pitman, Charles W. Harrison, Jerry E. Quasny
  • Patent number: 4088565
    Abstract: A process for dewaxing waxy petroleum distillate oil stock wherein one volume waxy oil stock is mixed with about 0.5-2 volumes aromatic hydrocarbon dewaxing solvent, and the oil/aromatic solvent mixture heated to a temperature for dissolving all solid wax therein, wherein the oil/aromatic solvent mixture is cooled at a rate of about 1.degree.-8.degree. F./min. to a selected separation temperature for precipitating wax crystals and forming a wax/oil/aromatic solvent mixture, wherein the wax/oil/aromatic solvent mixture is mixed with 0.5-2 volumes of ketone dewaxing solvent at said separation temperature for a residence time of about 15 seconds to two minutes for precipitating additional wax, and wherein solid wax and dewaxed oil are recovered as products of the process.
    Type: Grant
    Filed: July 5, 1977
    Date of Patent: May 9, 1978
    Assignee: Texaco Inc.
    Inventors: Leonard R. Watts, Norman L. Brewer
  • Patent number: 4024057
    Abstract: A grease removing device for removing liquid grease from solutions such as soups and broths and a method for using the device are disclosed. The grease removing device includes a flat plate having a multiplicity of projections on its undersurface. A container for holding coolant and a handle are also provided. In operation, the plate is cooled to a temperature lower than the freezing point of the grease; the undersurface of the plate is then brought into contact with the floating grease; and the plate with the attached solidified grease is then removed from the solution.
    Type: Grant
    Filed: June 4, 1976
    Date of Patent: May 17, 1977
    Inventor: Dorothy Joan McCoy
  • Patent number: 4013544
    Abstract: Hydrocarbon mixtures (e.g. "waxy" crude oils) are transported as a slurry by first fractionating the mixture into at least a relatively low pour point fraction and a relatively high pour point fraction. Thereafter, the high pour point fraction is congealed by dispersing it as particles into the bottom of a tower having a continuous stream of water flowing countercurrent to the dispersed fraction and wherein the water in at least the upper portion of the tower is at a temperature sufficient to congeal the dispersed particles. The particles pass upwardly through the tower and through an interface within the tower, the interface being the juncture of water and the low pour point fraction being introduced into the top portion of the tower. A portion of the resulting slurry is withdrawn and transported in a conduit at temperatures below those which bring about solution of the congealed particles in the low pour point fraction.
    Type: Grant
    Filed: August 21, 1974
    Date of Patent: March 22, 1977
    Assignee: Marathon Oil Company
    Inventor: LaVaun S. Merrill, Jr.
  • Patent number: 3972802
    Abstract: A dewaxing process is provided in which a mixture of a solvent comprising propylene-acetone and a waxy petroleum oil is contacted with a cold aqueous solution of acetone and methanol. The aqueous acetone-methanol solution, which is immiscible in the waxy oil-solvent mixture, cools the mixture thereby crystallizing a substantial portion of the wax in the mixture.
    Type: Grant
    Filed: June 5, 1975
    Date of Patent: August 3, 1976
    Assignee: Exxon Research and Engineering Company
    Inventor: James D. Bushnell
  • Patent number: RE30281
    Abstract: Hydrocarbon mixtures containing 1-80% wax, e.g. shale oil, can be transported in a pipeline by distilling the mixture into an overheads fraction and a bottoms fraction, cooling the overheads fraction to a temperature above its pour point, but to a temperature sufficiently low so that when it is admixed with the bottoms fraction, the composite temperature of the mixture will be at or below the temperature at which the mixture is to be transported, and admixing the overheads fraction with the bottoms fraction (at a temperature above that at which wax crystals form) while imparting to the mixture a shear rate less than about 20 sec.sup.-1 to form a pumpable slurry. The slurry is preferably transported in a pipeline at conventional temperatures.
    Type: Grant
    Filed: August 25, 1978
    Date of Patent: May 27, 1980
    Assignee: Marathon Oil Company
    Inventors: James E. Tackett, Paul H. Stewart