EP0321713A2 - Production d'un carburéacteur à haute densité à partir d'huiles de charbon - Google Patents

Production d'un carburéacteur à haute densité à partir d'huiles de charbon Download PDF

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Publication number
EP0321713A2
EP0321713A2 EP88119449A EP88119449A EP0321713A2 EP 0321713 A2 EP0321713 A2 EP 0321713A2 EP 88119449 A EP88119449 A EP 88119449A EP 88119449 A EP88119449 A EP 88119449A EP 0321713 A2 EP0321713 A2 EP 0321713A2
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EP
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Prior art keywords
hydrogenation
effected
hydrocracking
coal
temperature
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Application number
EP88119449A
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German (de)
English (en)
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EP0321713B1 (fr
EP0321713A3 (en
Inventor
Marvin Ira Greene
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CB&I Technology Inc
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Lummus Crest Inc
ABB Lummus Crest Inc
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    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G65/00—Treatment of hydrocarbon oils by two or more hydrotreatment processes only
    • C10G65/02—Treatment of hydrocarbon oils by two or more hydrotreatment processes only plural serial stages only
    • C10G65/12—Treatment of hydrocarbon oils by two or more hydrotreatment processes only plural serial stages only including cracking steps and other hydrotreatment steps

Definitions

  • This invention relates to the production of aviation fuels, and more particularly to the production of high density jet fuels (HDJF).
  • HDJF high density jet fuels
  • Prior art processes for producing HDJF generally involve the blending of various petroleum streams that are rich in two and three ring precursors. Such a procedure presents problems in that sufficient commercial quantities of such streams may not always be available in conventional petroleum processes.
  • Primary coal-derived liquids whether derived from thermal processes or hydrogenation processes, are viscous black oils characterized by high heteroatom content and high polynuclear aromatics content. Accordingly, they are deficient in hydrogen content with respect to comparable petroleum liquids and therefore require significant hydroprocessing to upgrade them to aviation turbine fuels and other clean distillate fuel products.
  • a further complication with regard to their hydroprocessability is that they are typically contaminated with coke precursors (i.e., Conradson Carbon Residue, preasphaltenes, etc.) and metals derived from the coal mineral matter.
  • coke precursors i.e., Conradson Carbon Residue, preasphaltenes, etc.
  • metals derived from the coal mineral matter i.e., metals derived from the coal mineral matter.
  • the present invention is directed to an improved process for producing high density jet fuel.
  • a high density jet fuel is produced by subjecting a coal derived heavy liquid to a series of processing steps, which includes hydrocracking to generate a vapor fraction including a distillate; denitrification of the vapor fraction; and saturation of aromatics to produce a product from which a high density jet fuel may be recovered.
  • the coal derived liquid is a heavy coal liquid, often referred to as a coal tar, which may be produced as a byproduct from coal gasification, coal pyrolysis, coal partial oxidation, coking, hydropyrolysis, hydrogenation, etc.
  • a coal tar generally has at least 25% thereof boiling above 850°F and most generally at least 50% boiling above 850°F (by volume).
  • the liquid may be dervied from a variety of coals or including but not limited to lignite, bituminous and subbituminous coals, etc.
  • the coal derived heavy liquid is initially subjected to hydrocracking in the presence of a hydrocracking catalyst.
  • a hydrocracking catalyst Such hydrocracking is preferably effected in the presence of a catalyst and at conditions which maximize the yield of 524°C- distillate.
  • hydrocracking is effected at a temperature of at least 370°C, and preferably at least 415°C. In most cases, the temperature does not exceed 468°C, and preferably does not exceed 454°C.
  • the hydrocracking is effected at elevated pressures, with the pressure generally exceeding 1,000 psig, and most generally exceeding 2,000 psig. In most cases, the pressure is not in excess of 3,000 psig. Hydrogen is added in an amount effective to accomplish the desired hydrocracking.
  • the hydrocracking is operated at a hydrogen partial pressure of at least 100 atmospheres, with the hydrogen partial pressure generally not exceeding 200 atmospheres.
  • the conditions are selected to provide a conversion to 524°C- distillate of at least 75%, and preferably at least 90%. In some cases, recycle of heavier materials is required in order to achieve such conversion.
  • the hydrocracking catalyst is of a type known in the art, and generally includes a Group VI or Group VIII hydrocracking component, preferably supported on a suitable support.
  • a combination of nickel oxide and molybdenum oxide; a combination of cobalt oxide and molybdenum oxide; molybdenum oxide, etc. with the support generally being an alumina support.
  • the hydrocracking is accomplished at liquid hourly space velocities of from 0.1 to 3.0.
  • the effluent from the hydrocracking includes both a vapor and a liquid fraction.
  • the vapor fraction is separated from such effluent, and such vapor fraction includes a distillate, with such distillate generally having a maximum nominal end point of about 400°C (atmospheric equivalent).
  • Such vapor fraction is generally separated from the hydrocracking effluent at essentially the reaction pressures.
  • the vapor fraction recovered from the hydrocracking, which includes distillate, is then subjected to hydrotreating by contacting such vapor fraction with hydrogen in the presense of a hydrogenation catalyst which preferably has denitrification activity.
  • the catalyst is preferably one which also has some hydrocracking activity to increase the content of distillates. Moreover, such catalyst should have some saturation activity to cap free radicals and to saturate olefinic unsaturation.
  • the hydrotreating is effected in a fixed bed and under conditions which reduce aromatics as well as the nitrogen content of the effluent to acceptable levels; for example, less than 500 parts per million, and preferably less than 1 part per million.
  • Such hydrotreating may be accomplished at temperatures of at least 315°C and preferably at least 345°C.
  • the temperature does not exceed 400 °C, and preferably does not exceed 370°C.
  • Such hydrotreating is generally accomplished at a hydrogen partial pressure of at least 70 atm, and in most cases, the hydrogen partial pressure does not exceed 200 atm.
  • suitable catalysts there may be mentioned catalysts from groups VI and/or VIII.
  • the catalyst is preferably supported on a suitable support.
  • the catalyst may be comprised of nickel oxide and tungsten oxide; molybdenum oxide and nickel oxide, which is preferably supported on an alumina support.
  • the effluent from the hydrotreating is separated into a C5- gas stream and a C5+distillate stream, with the C5 distillate stream then being subjected to additional hydrogenation in the presence of a hydrogenation catalyst to saturate aromatics. More particularly, aromatics are saturated in order to generate two and three ring cycloparaffins.
  • the hydrogenation to effect saturation of aromatics is generally accomplished at a temperature of at least 260°C and preferably at least 287°C. In most cases, the temperature does not exceed 345°C, and preferably does not exceed 320°C.
  • the saturation is accomplished at a pressure of at least 68 atm, and preferably at least 100 atm. In most cases, the pressure does not exceed about 170 atm.
  • the saturation is generally accomplished at a hydrogen partial pressure of at least 55 atm, and generally the hydrogen partial pressure does not exceed 140 atm. Space velocities are generally in the order of 0.5 to 4.0 hours ⁇ 1.
  • the hydrogenation is preferably effected in the presence of the catalyst at conditions to provide an effluent having less than 25%, by weight of aromatics.
  • the catalyst which is employed for saturation of aromatics includes a hydrogenation component such as nickel oxide on silica-alumina, in acidic form, or may be comprised of molybdenum oxide and nickel oxide on alumina having high loading of molybdenum oxide at low density or may be a Y-type zeolite. It is to be understood that if there is a sufficient reduction of aromatic content during the initial hydrotreating, then within the scope of the invention the subsequent hydrogenation could be eliminated.
  • the effluent from the saturation is quenched, depressurized and the product is fractionated to recover a high density jet fuel fraction.
  • a gasoline fraction and a bottoms cut which may be recycled to the saturation stage.
  • the recycle cut point of the distillation bottoms can be varied between 176°C and 400°C as necessary to control the smoke point, energy density, aromatic content and freeze point of the high density jet fuel (HDJF).
  • a high density jet fuel has at least 95 volume percent thereof boiling below about 690°F and preferably below 550°F; an API gravity of no greater than 35°, and a hydrogen content of at least 12% and preferably at least 13.5%, by weight.
  • the 5 volume percent boiling point is preferably no less than 250°F and most preferably no less than 300°F.
  • the drawing is a simplified schematic flow diagram of an embodiment of a process in accordance with the present invention.
  • coal derived heavy liquid in line 10 is combined with recycle in line 11, and the combined feed introduced into a hydrocracking zone, schematically generally indicated as 13, along with hydrogen gas in line 14.
  • the hydrocracking zone 13 is preferably comprised of one or more expanded bed reactors wherein the combined feed and hydrogen flow upwardly through an expanded bed of hydrocracking catalyst of the type hereinabove described.
  • an expanded bed hydrocracking operation is preferred, it is possible to accomplish such hydrocracking by other processing techniques, such as a fixed bed operation employing a plurality of beds.
  • the hydrocracking zone is operated at conditions hereinabove described to produce an effluent containing a liquid fraction and a vapor fraction with the vapor including a distillate which boils below about 400°C.
  • An effluent is drawn from the hydrocracking zone 13 through line 15, and is cooled in cooler 16, with the cooled effluent being introduced into a vapor liquid separation zone, schematically generally indicated as 17.
  • a separated liquid fraction is recovered through line 18, and all or a portion thereof is recycled through line 11, with the remaining product being recovered through line 19.
  • the liquid fraction recovered in line 18 generally has a boiling point in excess of 400°C, and is recycled through line 11 in an amount to achieve the desired conversion in hydrocracking zone 13.
  • the remaining 400°C plus fraction recovered through line 19 may be employed as a feed to a partial oxidation unit to produce synthesis gas.
  • the separated vapor fraction is recovered through line 21, and immediately introduced without condensation into a hydrotreating zone, schematically generally indicated as 22 along with hydrogen gas in line 23.
  • the hydrotreating zone is comprised of an upflow fixed catalyst bed reactor; however, other types of reactors may be employed.
  • the denitrification zone 22 is operated at a temperature lower than hydrocracking zone 13.
  • the hydrotreating zone 22 employs a catalyst, and is operated at conditions as hereinabove described in order to saturate some aromatics as well as reduce the nitrogen content of the vapor fraction.
  • some hydrocracking may be effected in zone 22, as well as capping of free radicals and reduction of olefinic unsaturation. As shown, the denitrification is effected in the vapor phase.
  • a hydrotreated effluent is withdrawn from the hydrotreating zone 22 through line 24, and such effluent is quenched in cooler 25 and depressured through valve 26 into a vapor-liquid separation zone, schematically generally indicated as 27.
  • a C5 ⁇ gas stream is recovered through line 28 and a C5+ liquid stream is recovered through line 29.
  • the liquid distillate in line 29 is combined with a recycle stream in line 31, as hereinafter described, and the combined stream in line 32 is introduced into a hydrogenation zone, schematically generally indicated as 33 which is operated with a catalyst and at conditions to effect saturation of aromatics.
  • hydrogenation zone 33 is an upflow fixed bed reactor wherein hydrogenation is effected in the liquid phase; however, it is to be understood that other types of reactors may be employed.
  • hydrogenation zone 33 is operated at a temperature lower than the temperature of hydrotreating zone 22; e.g., 25°C to 55°C less than zone 22.
  • An effluent having a reduced quantity of aromatics is withdrawn from zone 33 through line 34, cooled in cooler 35, and depressurized prior to introduction into a separation and recovery zone, which is generally shown as a distillation tower 39.
  • distillation zone 39 there is recovered a gas fraction through line 40, a gasoline fraction through line 36, a high density jet fuel through line 37, and a recycle fraction through line 31.
  • the recycle fraction in line 31 generally has a cut point of at least 176°C, and preferably at least 204°C with the maximum cut point being about 400°C.
  • the cut point of such recycle fraction can be varied as necessary to control the smoke point, energy density, aromatics content and freeze point of the high density jet fuel product recovery through line 37.
  • North Dakota Lignite tar oil having the following properties: Specific Gravity 1.076 Viscosity at 210F, cst 42 Pour Pt, C 38 Elementals, wt % C 81.99 H 8.53 N 1.10 S 0.72 O 7.42 Ash 0.24 Distillation, °F IBP 425 50% distilled 900
  • the hydrocracked products were recovered by conventional means to produce a light oil, heavy oil and residual oil product.
  • the heavy oil was fed to a trickle-bed hydrotreater operated at 350C, 2500 psig total pressure, 2000 psig hydrogen partial pressure, LHSV of 1.0 hr ⁇ 1 over NiWS/SiO2-­Al2O3 catalyst.
  • Hydrogen consumption was 1450 scf/bbl.
  • Nitrogen level in the product was 1 ppm. Aromatics were reduced from 80% to 35%.
  • the yield of HDJF was 82 liq vol % on the coal tar feed.
  • the hydrocracked products from the expanded-bed hydrocracker were separated in a V/L separator with the resultant vapors, without condensation, fed in an upflow manner directly to a fixed-bed hydrotreater.
  • the latter was operated at 350C, 2000 psig total pressure, 1600 psig hydrogen partial pressure, and GHSV of 0.75 hr ⁇ 1 over NiWS/SiO2-Al2O3 catalyst. Hydrogen consumption was 1150 scf/bbl. Nitrogen level in the product was 1 ppm. Aromatics were 48%.
  • the present invention is advantageous in that it is possible to effectively produce HDJF from coal derived liquids.
  • the present invention has particular applicability to liquids, derived from coal gasification and/or coal pyrolysis in that such liquids are particularly difficult to convert to HDJF in that they are more deficient in hydrogen than coal liquids derived by hydroliquification techniques.
  • desirable specifications for HDJF e.g., API gravity of no greater than 35°, hydrogen content of at least 12% and preferably at least 13.5%, all by weight; paraffin content of less than 10%, and an aromatic content of less than 25%.
  • such HDJF may be produced in increased yields.

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  • Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
EP19880119449 1987-12-21 1988-11-23 Production d'un carburéacteur à haute densité à partir d'huiles de charbon Expired - Lifetime EP0321713B1 (fr)

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US13540187A 1987-12-21 1987-12-21
US135401 1987-12-21

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EP0321713A2 true EP0321713A2 (fr) 1989-06-28
EP0321713A3 EP0321713A3 (en) 1990-02-07
EP0321713B1 EP0321713B1 (fr) 1993-03-10

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1319701A1 (fr) * 2001-12-17 2003-06-18 Chevron USA, Inc. Procédé de préparation de distillats moyens de haute qualité d'hydrocraqueurs doux et d'hydrotraiteurs de gasole sous vide combiné avec alimentation externe à limite d'ébullition de distillats moyens
CN100419044C (zh) * 2005-07-15 2008-09-17 中国石油化工股份有限公司 一种从煤液化油最大量生产大比重航空煤油的方法
WO2014189743A1 (fr) * 2013-05-20 2014-11-27 Shell Oil Company Procédé de saturation de composés aromatiques pour diesel en deux étapes faisant appel à un catalyseur métallique commun
WO2014189744A1 (fr) * 2013-05-20 2014-11-27 Shell Oil Company Procédé de saturation de composés aromatiques pour diesel en deux étapes faisant appel à un balayage à la vapeur intermédiaire et à un catalyseur métallique commun

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3143489A (en) * 1961-11-24 1964-08-04 Consolidation Coal Co Process for making liquid fuels from coal
GB989258A (en) * 1961-04-19 1965-04-14 Gulf Research Development Co Process for hydrocracking a hydrocarbon
US3592757A (en) * 1969-03-17 1971-07-13 Union Oil Co Combination hydrocracking-hydrogenation process

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE755268A (fr) * 1970-08-01 1971-02-25 Texaco Development Corp Production de carburants pour moteurs et moteurs a reaction,

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB989258A (en) * 1961-04-19 1965-04-14 Gulf Research Development Co Process for hydrocracking a hydrocarbon
US3143489A (en) * 1961-11-24 1964-08-04 Consolidation Coal Co Process for making liquid fuels from coal
US3592757A (en) * 1969-03-17 1971-07-13 Union Oil Co Combination hydrocracking-hydrogenation process

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1319701A1 (fr) * 2001-12-17 2003-06-18 Chevron USA, Inc. Procédé de préparation de distillats moyens de haute qualité d'hydrocraqueurs doux et d'hydrotraiteurs de gasole sous vide combiné avec alimentation externe à limite d'ébullition de distillats moyens
US6787025B2 (en) 2001-12-17 2004-09-07 Chevron U.S.A. Inc. Process for the production of high quality middle distillates from mild hydrocrackers and vacuum gas oil hydrotreaters in combination with external feeds in the middle distillate boiling range
CN100419044C (zh) * 2005-07-15 2008-09-17 中国石油化工股份有限公司 一种从煤液化油最大量生产大比重航空煤油的方法
WO2014189743A1 (fr) * 2013-05-20 2014-11-27 Shell Oil Company Procédé de saturation de composés aromatiques pour diesel en deux étapes faisant appel à un catalyseur métallique commun
WO2014189744A1 (fr) * 2013-05-20 2014-11-27 Shell Oil Company Procédé de saturation de composés aromatiques pour diesel en deux étapes faisant appel à un balayage à la vapeur intermédiaire et à un catalyseur métallique commun
US9528052B2 (en) 2013-05-20 2016-12-27 Shell Oil Company Two stage diesel aromatics saturation process using base metal catalyst
US9683182B2 (en) 2013-05-20 2017-06-20 Shell Oil Company Two-stage diesel aromatics saturation process utilizing intermediate stripping and base metal catalyst
RU2671978C2 (ru) * 2013-05-20 2018-11-08 Шелл Интернэшнл Рисерч Маатсхаппий Б.В. Двухступенчатый способ насыщения ароматических соединений дизельного топлива, использующий промежуточное отпаривание, и катализатор на основе неблагородного металла
RU2695377C2 (ru) * 2013-05-20 2019-07-23 Шелл Интернэшнл Рисерч Маатсхаппий Б.В. Двухступенчатый способ насыщения ароматических соединений дизельного топлива, использующий катализатор на основе неблагородного металла

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Publication number Publication date
DE3879132D1 (de) 1993-04-15
EP0321713B1 (fr) 1993-03-10
EP0321713A3 (en) 1990-02-07

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