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EP0156614B1 - Cokéfaction de résidu en présence d'un donneur d'hydrogène - Google Patents

Cokéfaction de résidu en présence d'un donneur d'hydrogène Download PDF

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Publication number
EP0156614B1
EP0156614B1 EP85301883A EP85301883A EP0156614B1 EP 0156614 B1 EP0156614 B1 EP 0156614B1 EP 85301883 A EP85301883 A EP 85301883A EP 85301883 A EP85301883 A EP 85301883A EP 0156614 B1 EP0156614 B1 EP 0156614B1
Authority
EP
European Patent Office
Prior art keywords
hydrogen
donating
diluent
feedstock
zone
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP85301883A
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German (de)
English (en)
Other versions
EP0156614A3 (en
EP0156614A2 (fr
Inventor
Hanbury John Woods
Frank Souhrada
Kenneth Robert Dymock
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Gulf Canada Ltd
Original Assignee
Gulf Canada Resources Inc
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Filing date
Publication date
Application filed by Gulf Canada Resources Inc filed Critical Gulf Canada Resources Inc
Publication of EP0156614A2 publication Critical patent/EP0156614A2/fr
Publication of EP0156614A3 publication Critical patent/EP0156614A3/en
Application granted granted Critical
Publication of EP0156614B1 publication Critical patent/EP0156614B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
    • C10B57/00—Other carbonising or coking processes; Features of destructive distillation processes in general
    • C10B57/04—Other carbonising or coking processes; Features of destructive distillation processes in general using charges of special composition
    • C10B57/045—Other carbonising or coking processes; Features of destructive distillation processes in general using charges of special composition containing mineral oils, bitumen, tar or the like or mixtures thereof
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
    • C10B55/00—Coking mineral oils, bitumen, tar, and the like or mixtures thereof with solid carbonaceous material
    • 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
    • C10G9/00—Thermal non-catalytic cracking, in the absence of hydrogen, of hydrocarbon oils
    • C10G9/005—Coking (in order to produce liquid products mainly)

Definitions

  • the present invention relates to a process for obtaining increased yields of liquid hydrocarbons from coking feedstocks by introducing hydrogen-donating hydrocarbon material together with the feedstock.
  • a gas oil and/or residuum is heated rapidly to coking temperature, initiating thermal breakdown, and passed into a coking drum, where the hot material continues thermal breakdown and conversion to lighter hydrocarbons and coke.
  • Coke yields in such processes can be as large as 30% or more, and the production of large amounts of this low-valued material is uneconomic.
  • Processes known in the art include the manufacture of premium coke, that is, coke having a low coefficient of thermal expansion (CTE), which is higher-valued than conventional coke.
  • CTE coefficient of thermal expansion
  • Wilson et al in U.S. Patent 3 617 513, disclosed a process for converting coal into liquid hydrocarbon products.
  • Coal was slurried with a hydrogen donor solvent boiling in the range from 177°C to 482°C, liquefied and the bottoms, containing liquid liquefaction products, non-liquefied solid coal particles and unconsumed hydrogen-donor solvent was passed to a fluid coking zone.
  • Operating conditions in the fluid coking zone included temperatures of from 538°C to 816°C.
  • the present invention provides a method for treating heavy hydrocarbonaceous oil feedstock, comprising:
  • the invention also resides in a method for reducing the amount of coke production in the coking of heavy hydrocarbonaceous oil feedstock, comprising the steps as listed above.
  • the process of the invention utilises a hydrogen-donating hydrocarbon diluent to provide sufficient hydrogen to add to at least a portion of the radicals that are created from the residuum feedstock when it is exposed to temperatures in the coking range, i.e. from 420°C to 500°C.
  • the hydrogen-donating diluent has a boiling range from 180°C to 400°C, preferably from 200°C to 350°C, at atmospheric pressure.
  • the donor diluent can be a highly aromatic light cycle oil generated in a catalytic cracking process; the oil is partially hydrogenated by known methods to produce a hydrogen donor diluent containing, for example, tetralin and substituted tetralins.
  • hydrogen-donating compounds and hydrogen donor precursors together comprise at least 40 percent of the hydrogen donor diluent.
  • Hydrocarbons boiling in the upper portion of the aforementioned broad boiling range that is, boiling from about 350°C to 400°C, generally participate to a minor degree, if at all, as hydrogen-donating materials during donor hydrocracking.
  • Some of those hydrocarbons, called herein hydrogen donor precursors are converted during donor hydrocracking into compounds that can be partially hydrogenated to hydrogen-donating compounds boiling in the aforementioned broad boiling range.
  • the hydrogen-donating diluent can advantageously include materials boiling up to 400°C.
  • the proportion of hydrogen-donating hydrocarbon diluent in relation to the residuum feedstock can be from about 0.02:1 to 1.0:1, preferably from 0.15:1 to 0.5:1.
  • a portion of the hydrogen donor requirement can be supplied by recycled hydrogen donor material obtained by fractionating the coker liquids product and partially hydrogenating at least a portion of a 180°C to 400°C donor precursor fraction, or preferably a 200°C to 350°C fraction, to produce a recycle hydrogen donor material.
  • the ratio of recycle hydrogen donor material to fresh hydrogen donor material can be from 0.1:1 to 2:1.
  • the temperature of the reaction mass entering the coker from a transfer tube can be in the range from 420°C to 500°C, preferably from 450°C to 500°C.
  • the relationship of time in the heating zone and temperature of that zone is governed by the nature of the heavy hydrocarbonaceous oil being treated. Oils that tend to crack easily are kept for a shorter residence time or at a lower temperature, or both, than oils that are more refractory.
  • the heavy hydrocarbonaceous oil feedstock can comprise a residuum from atmospheric or vacuum distillation of conventional crude oil, or an atmospheric or vacuum residuum of heavy oil or bitumen.
  • bitumen can be used as the feedstock oil.
  • Mixtures of the above-mentioned oils can also be fed to the process.
  • a high temperature requires a short residence time in the heating zone, as is known to those skilled in the art.
  • the temperature maintained in a coke drum is generally 16wer than the material in the transfer tube, and can be from 400°C to 480°C.
  • Operating pressure can be from atmospheric, i.e. 101 kPa, to about 600 kPa, preferably from 200 kPa to 400 kPa.
  • the liquid product material obtained from an overhead stream off the coke drum can be fractionated. At least a portion of a material boiling in the heavy gas oil range, i.e. above 400°C, can be recycled to be mixed with fresh residuum feedstock.
  • the bottoms recycle-to-fresh residuum feed ratio can be up to about 0.4:1. In refinery operation, a bottoms recycle-to-fresh feed ratio of 0.1:1 to 0.3:1 is generally sufficient to remove the entire heavy gas oil product.
  • both hydrogen donor material and heavy gas oil can be recycled.
  • the hold time of reaction mass in the coke drum can be from 5 minutes to 60 minutes.
  • delayed coking according to the invention is performed using two coke drums alternately. When one of the drums is filled with coke, it is disconnected from the preheating furnace and the coke product is discharged while the other drum is being filled with reaction mass from a preheating furnace via a transfer tube. The initial reaction mass entering either coke drum after startup of that drum is subjected to a longer period of exposure to coking conditions than the last reaction mass prior to shutdown of that drum. The method of the invention can be performed in such refinery conditions.
  • Figure 1 the single drawing, represents a preferred form of apparatus for carrying out the process of the invention.
  • vacuum residuum feedstock is fed by lines 11 and 13 to surge drum 2.
  • Partially hydrogenated light cycle oil is fed by line 12, and blended with residuum to be fed into drum 2 by line 13, and optionally recycled gas oil is added by line 17.
  • the resulting blend is taken through line 14 to coker preheating furnace 6 where it is heated to coking temperature, typically 420°C to 500°C, thence by line 15 to coke drum 7 or coke drum 7a.
  • the drum not being filled at the time is cut off from the system by valves 3 and 4 or 3a and 4a.
  • the drum After a suitable holding period in the coke drum, at a temperature from 400°C to 480°C, and a pressure substantially lower than the pressure in the preheating furnace 6, during which period coker overheads are removed by line 16 to fractionator 8 from which products from gases to heavy gas oil are withdrawn by lines 21 to 24, the drum is taken out of service and its coke content removed via line 18 or 18a.
  • at least a portion of heavy gas oil boiling above 400°C can be recycled via line 17 for further treatment in the coker, and if desired, all of the heavy gas oil can be thus converted to lighter petroleum products or to coke. Where such stream is not recycled, it can advantageously be fed to a fluid catalytic cracking zone.
  • a portion of the hydrogen donor requirement can be satisfied by passing through line 19 at least a portion of the gas oil fraction in line 23 boiling between 180°C and 400°C, preferably between 200°C and 350°C, partially hydrogenating the gas oil in hydrogenation zone 9 and recycling the resulting recycle hydrogen donor material through line 20 to blend with fresh donor fed by line 12.
  • the blend was heated to 493°C in a commercial-scale coker furnace at 1.48 MPa (absolute) and passed through a pressure reducing valve into a coke drum where the reaction mass was held at 471°C and 240 kPa as the coke drum filled with coke.
  • Coker overheads were taken off the fractionator with yields (net of the added cycle oil) shown as Run 1 in Table 1.
  • the coke product contained 12 percent Volatile Combustible Matter (VCM).
  • VCM Volatile Combustible Matter
  • the process of the invention is thus shown to be effective in lowering the production of coke on both laboratory-scale and commercial-scale apparatus. Additional advantages are that the process produces a more saturated gasoline product than conventional processes, and reduces fouling of furnace tubes in the heating zone.

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  • Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
  • Coke Industry (AREA)

Claims (11)

1. Un procédé pour traiter une charge d'huile hydrocarbonée lourde qui consiste:
(a) à mélanger la charge d'huile hydrocarbonée lourde et un diluant hydrocarboné donneur d'hydrogène bouillant dans un intervalle de 180 à 400°C sous pression atmosphérique, dans un rapport à ladite charge de 0,02:1 à 1,0:1 en poids dans une zone de mélange;
(b) à chauffer le mélange de la charge et du diluant hydrocarboné donneur d'hydrogène à une température de 420 à 500°C dans une zone de chauffage pour former une masse de réaction;
(c) à maintenir la masse de réaction dans une zone de cokéfaction à une température de 400 à 480°C et sous une pression de 101 à 600 kPa pendant une durée de séjour de 5 à 60 min; et
(d) à récupérer les hydrocarbures liquides produits et le coke de la zone de cokéfaction.
2. Un procédé selon la revendication 1, dans lequel ledit diluant donneur d'hydrogène comprend une huile de recyclage légère partiellement hydrogénée, dans laquelle les hydrocarbures donneurs d'hydrogène et les précurseurs de donneurs d'hydrogène constituent ensemble au moins 40% de ladite huile de recyclage légère.
3. Un procédé selon la revendication 1 ou 2, dans lequel ledit diluant donneur d'hydrogène bout dans un intervalle de 200 à 350°C sous la pression atmosphérique.
4. Un procédé selon l'une quelconque des revendications 1 à 3, dans lequel ledit diluant hydrocarboné donneur d'hydrogène est mélangé avec ladite charge d'huile hydrocarbonée lourde dans un rapport à ladite charge de 0,15:1 à 0,5:1.
5. Un procédé selon l'une quelconque des revendications 1 à 4, dans lequel lesdites conditions dans la zone de chauffage comprennent une température dans l'intervalle de 450 à 500°C.
6. Un procédé selon l'une quelconque des revendications 1 à 5, dans lequel ladite pression dans ladite zone de cokéfaction est de 200 à 400 kPa.
7. Un procédé selon l'une quelconque des revendications 1 à 6, caractérisé en outre en ce que:
(a) on fractionne lesdits hydrocarbures liquides récupérés pour en séparer des courants d'hydrocarbures bouillant au-dessous de 400°C pour produire une fraction lourde de gazole bouillant dans un intervalle au-dessus de 400°C; et
(b) on recycle au moins une portion de ladite fraction lourde de gazole dans ladite zone de mélange.
8. Un procédé selon la revendication 7, dans laquelle le rapport de ladite fraction lourde de gazole à ladite charge d'huile hydrocarbonée lourde est de 0,1:1 à 0,3:1.
9. Un procédé selon la revendication 7 ou 8, dans laquelle la quantité totale de ladite fraction lourde de gazole est recyclée dans ladite zone de mélange.
10. Un procédé selon l'une quelconque des revendications 1 à 9, caractérisé en ce que:
(a) on fractionne lesdits hydrocarbures liquides récupérés pour en séparer une fraction de précurseurs de donneurs bouillant dans un intervalle d'environ 180 à 400°C;
(b) on hydrogène partiellement au moins une portion de ladite fraction de précurseurs de donneurs pour produire un produit donneur d'hydrogène de recyclage; et
(c) on recycle ledit produit donneur d'hydrogène de recyclage pour former au moins une portion dudit diluant donneur d'hydrogène.
11. Un procédé selon la revendication 10, dans lequel ledit produit donneur d'hydrogène de recyclage est utilisé dans un rapport au diluant donneur d'hydrogène frais de 0,1:1 à 2:1.
EP85301883A 1984-03-20 1985-03-19 Cokéfaction de résidu en présence d'un donneur d'hydrogène Expired - Lifetime EP0156614B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CA450003 1984-03-20
CA000450003A CA1246481A (fr) 1984-03-20 1984-03-20 Cokefaction de residus en presence d'hydrogene donneur

Publications (3)

Publication Number Publication Date
EP0156614A2 EP0156614A2 (fr) 1985-10-02
EP0156614A3 EP0156614A3 (en) 1987-08-05
EP0156614B1 true EP0156614B1 (fr) 1990-12-12

Family

ID=4127451

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85301883A Expired - Lifetime EP0156614B1 (fr) 1984-03-20 1985-03-19 Cokéfaction de résidu en présence d'un donneur d'hydrogène

Country Status (9)

Country Link
EP (1) EP0156614B1 (fr)
JP (1) JPS60238388A (fr)
AU (1) AU580035B2 (fr)
BR (1) BR8501214A (fr)
CA (1) CA1246481A (fr)
DE (1) DE3580859D1 (fr)
ES (1) ES8608564A1 (fr)
NO (1) NO851067L (fr)
ZA (1) ZA851903B (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105505449A (zh) * 2015-11-27 2016-04-20 中国海洋石油总公司 一种供氢焦化方法

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0718265A (ja) * 1993-07-01 1995-01-20 Kurita Water Ind Ltd 石油化学プロセス用汚れ防止剤
US6919017B2 (en) * 2002-04-11 2005-07-19 Conocophillips Company Separation process and apparatus for removal of particulate material from flash zone gas oil
US9039889B2 (en) * 2010-09-14 2015-05-26 Saudi Arabian Oil Company Upgrading of hydrocarbons by hydrothermal process
CN105331390A (zh) * 2015-11-27 2016-02-17 中国海洋石油总公司 一种供氢延迟焦化的方法
US20230168157A1 (en) * 2021-11-29 2023-06-01 Petróleo Brasileiro S.A. - Petrobras System and method for evaluation of the deposition in tubes of the furnaces of a delayed coking unit

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3617513A (en) * 1969-01-03 1971-11-02 Exxon Research Engineering Co Coking of heavy feedstocks
JPS5455005A (en) * 1977-10-12 1979-05-01 Chiyoda Chem Eng & Constr Co Ltd Cracking of heavy hydrocarbons to lighter grade
US4213846A (en) * 1978-07-17 1980-07-22 Conoco, Inc. Delayed coking process with hydrotreated recycle
US4176046A (en) * 1978-10-26 1979-11-27 Conoco, Inc. Process for utilizing petroleum residuum
DE2949935C2 (de) * 1979-12-12 1985-06-05 Metallgesellschaft Ag, 6000 Frankfurt Verfahren zur Umwandlung von hochsiedenden Rohölen in erdölähnliche Produkte
CA1122914A (fr) * 1980-03-04 1982-05-04 Ian P. Fisher Methode de valorisation des hydrocarbures lourds
US4385980A (en) * 1981-02-26 1983-05-31 Conoco Inc. Coal treating process

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105505449A (zh) * 2015-11-27 2016-04-20 中国海洋石油总公司 一种供氢焦化方法

Also Published As

Publication number Publication date
NO851067L (no) 1985-09-23
ES541382A0 (es) 1986-07-16
BR8501214A (pt) 1985-11-12
EP0156614A3 (en) 1987-08-05
AU4002285A (en) 1985-09-26
ZA851903B (en) 1985-10-30
DE3580859D1 (de) 1991-01-24
EP0156614A2 (fr) 1985-10-02
ES8608564A1 (es) 1986-07-16
JPS60238388A (ja) 1985-11-27
AU580035B2 (en) 1988-12-22
CA1246481A (fr) 1988-12-13

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