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CN-120699667-B - Method and device for increasing yield of high-quality low-sulfur petroleum coke

CN120699667BCN 120699667 BCN120699667 BCN 120699667BCN-120699667-B

Abstract

The invention relates to the technical field of petrochemical industry, in particular to a method and a device for increasing yield of high-quality low-sulfur petroleum coke. The method comprises the steps of carrying out hydrodesulfurization pretreatment on raw oil and a catalyst, carrying out heat treatment on the obtained liquid-solid component I, carrying out separation and extraction on the obtained liquid-solid component II, and carrying out coking treatment on the obtained coking raw material to obtain low-sulfur petroleum coke with the sulfur content less than or equal to 2wt%, wherein the catalyst is selected from at least one complex formed by bonding active metal and an organic ligand through coordination bonds. The method provided by the invention not only realizes the efficient conversion of the raw oil and increases the yield of the high-quality petroleum coke, but also widens the raw materials of the low-sulfur petroleum coke and realizes the economic added value of the raw oil, especially the high-sulfur inferior raw oil.

Inventors

  • TAO MENGYING
  • HOU HUANDI
  • LIU ZIBIN
  • WANG TING
  • DONG MING
  • ZHAO FEI

Assignees

  • 中国石油化工股份有限公司
  • 中石化石油化工科学研究院有限公司

Dates

Publication Date
20260505
Application Date
20240326

Claims (20)

  1. 1. The method for increasing yield of high-quality low-sulfur petroleum coke is characterized by comprising the steps of (1) carrying out hydrodesulfurization pretreatment on raw oil and a catalyst in the presence of hydrogen to obtain a liquid-solid component I and a gas I; (2) Carrying out heat treatment on the liquid-solid component I to obtain a liquid-solid component II and a gas II; (3) Separating and extracting the liquid-solid component II to obtain external tail oil, light components and heavy components; (4) Carrying out coking treatment on the heavy component serving as a coking raw material to obtain low-sulfur petroleum coke with the sulfur content of less than or equal to 2 wt%; wherein the separation and extraction is selected from extraction separation-distillation coupling or distillation cutting; the conditions of the hydrodesulfurization pretreatment comprise 380-440 ℃, 8-20MPa of hydrogen partial pressure, 0.05-0.6h -1 of volume space velocity and 200-20000 mug/g of catalyst concentration calculated by metal element; The heat treatment conditions comprise 380-440 ℃, 0.1-4MPa and 10-120min, wherein the heat treatment is carried out in an air atmosphere or an inert atmosphere; The coking treatment conditions comprise the temperature of 500-600 ℃, the pressure of 0.15-0.3MPa, the time of 1-5h and the circulation ratio of 0-1; Wherein the catalyst is selected from at least one complex formed by coordination bonding of an active metal and an organic ligand; The catalyst has a composition shown in a formula (I), wherein MO a [R(COO) x ] b (I), wherein M is selected from at least one metal element in VB group, VIB group, VIII group and IB group, R is selected from C 3 -C 20 alkyl, x is selected from 1,2 and 3, a is selected from positive numbers of 0-5, and b is selected from positive numbers of 1-6; The active metal content of the catalyst is 5-35wt% based on M.
  2. 2. The process according to claim 1, wherein the conditions of the hydrodesulfurization pretreatment include a temperature of 400 to 430 ℃, a hydrogen partial pressure of 10 to 18MPa, a volume space velocity of 0.1 to 0.5h -1 , and a concentration of the catalyst in terms of metal element of 500 to 10000. Mu.g/g; and/or, the hydrodesulfurization pretreatment is performed in a slurry bed reactor; And/or, in the raw oil, the sulfur content is more than or equal to 3wt%, the asphaltene content is more than or equal to 11wt%, the heavy metal content calculated by Ni and/or V is more than or equal to 150ppm, and the kinematic viscosity at 100 ℃ is more than or equal to 2000mm 2 /s; and/or the raw oil is selected from high-sulfur inferior oil.
  3. 3. The method of claim 1, wherein the feedstock oil is selected from at least one of a high sulfur crude oil, a high sulfur deasphalted oil, and a high sulfur vacuum residuum.
  4. 4. The method of claim 1, wherein in formula I, M is selected from at least one metal element of V, cr, mo, W, fe, co, ru, ni, cu and Pd, R is selected from C 4 -C 20 normal alkyl, C 4 -C 20 isopolyalkyl, C 5 -C 20 cycloalkyl-containing and C 6 -C 20 aryl, x is selected from 1, 2, a is selected from positive numbers of 1-3, and b is selected from positive numbers of 2-5.
  5. 5. The method of claim 4, wherein in formula I, M is selected from at least one metal element of Mo, W, ni, V, co and Fe, and R is selected from C 5 -C 11 normal alkyl, C 5 -C 11 isopolyl, C 5 -C 12 cycloalkyl-containing, and C 6 -C 12 aryl.
  6. 6. The method of claim 1, wherein the infrared spectrum of the catalyst has a characteristic peak of M-O, M =o vibration at position 700-1000cm -1 and a characteristic peak of-C (=o) -O group coordination to metal M at positions 1350-1450cm -1 and 1500-1610cm -1 .
  7. 7. The process according to claim 1, wherein the active metal content in the catalyst, expressed as M, is 8-25wt%.
  8. 8. The process according to claim 7, wherein the active metal content in the catalyst, expressed as M, is 10-25wt%.
  9. 9. The process according to claim 8, wherein the active metal content in the catalyst, expressed as M, is 10-20wt%.
  10. 10. The method according to claim 1, wherein the heat treatment conditions include a temperature of 400-430 ℃, a pressure of 1-3MPa, and a time of 20-100min; And/or, the heat treatment is performed in an inert atmosphere.
  11. 11. The process according to claim 1, wherein the liquid-solid component II satisfies a weight loss of < 15% by weight for a fraction of 0% by weight < 5% by weight of toluene insolubles and 0% by weight < greater than 350 ℃.
  12. 12. The process according to claim 11, wherein the liquid-solid component II satisfies a weight loss of < 10% by weight for a fraction of 0% by weight < 3% by weight of toluene insolubles and 0% by weight < more than 350 ℃.
  13. 13. The process according to claim 1, wherein the liquid-solid component II also satisfies a sulfur content of not more than 2% by weight and a carbon residue content of not less than 7% by weight.
  14. 14. The process according to claim 13, wherein the liquid-solid component II satisfies a sulfur content of 1.5 wt.% or less and a carbon residue content of 10 wt.% or more.
  15. 15. The method according to claim 1, wherein when the separation and extraction is selected from the group consisting of extraction separation-distillation coupling, the extraction separation-distillation coupling process comprises contacting the liquid-solid component II with a solvent and performing extraction separation to obtain the external tail-flick oil and the solid-removal oil, and distilling the solid-removal oil to obtain the light component and the heavy component.
  16. 16. The process of claim 15, wherein the extraction separation conditions comprise a temperature of 40-300 ℃, a pressure of 0.1-6MPa, and a weight ratio of solvent to de-solidified oil of 1-10:1.
  17. 17. The process of claim 16, wherein the extraction separation conditions comprise a temperature of 80-240 ℃, a pressure of 0.1-3MPa, and a weight ratio of solvent to de-solidified oil of 1-5:1.
  18. 18. The method of claim 15, wherein the distillation temperature is ≡330 ℃.
  19. 19. The method of claim 18, wherein the temperature of the distillation is 330-370 ℃.
  20. 20. The method of claim 15, wherein the solvent is selected from at least one of C 3 -C 8 alkanes, C 3 -C 8 olefins, toluene, and light naphtha.

Description

Method and device for increasing yield of high-quality low-sulfur petroleum coke Technical Field The invention relates to the technical field of petrochemical industry, in particular to a method for increasing yield of high-quality low-sulfur petroleum coke and a device for increasing yield of high-quality low-sulfur petroleum coke. Background Petroleum coke is a solid product obtained by a delayed coking device of a petroleum refinery, and is an irreplaceable production raw material in a plurality of industries such as glass, steel, electrolytic aluminum and the like. The quality of petroleum coke products is greatly affected by the variety of crude oil processed by refineries, and most of sulfur and impurities in the crude oil are enriched in petroleum coke. According to sulfur content classification, the petroleum coke with the sulfur mass fraction not more than 3wt% is called low sulfur petroleum coke and is mainly used for manufacturing electrodes in the steel-making and aluminum-making industries, and the petroleum coke with the sulfur content higher than 3wt% is called high sulfur coke, is an economic fuel capable of replacing power coal and is mainly used as fuel in cement, electric power and steel-making industries. In most countries in the world, the petroleum coke with high sulfur content is mainly used as the fuel of power plants, and the petroleum coke with high quality and low sulfur content is widely applied in the industries of steelmaking, aluminum smelting and carbon, so that the value of the petroleum coke with low sulfur content is greatly increased. Along with the continuous aggravation trend of petroleum resources, imported crude oil, particularly high-sulfur crude oil, in China is gradually increased, and the yield of high-sulfur petroleum coke is increased. Reducing the sulfur content of coker feedstock is critical to reducing high sulfur coke yield and producing low sulfur coke. The combined process of residual oil hydrogenation and delayed coking can solve the problem of high sulfur content of petroleum coke faced by the delayed coking process. However, the hydrodesulfurization also inevitably brings about the loss of the coke-producing effective component, namely carbon residue, and how to obtain the coking raw material with high carbon residue content while effectively desulfurizing, thereby meeting the greatly increased low sulfur coke requirement of downstream industries, and being a factor which must be considered in the development process. CN201110353406.4 discloses a combined process method of residuum hydrotreatment and delayed coking, which is to mix residuum, coker wax oil and hydrogen, then enter a hydrotreater to react, mix the separated hydrogenated residuum and vacuum wax oil or enter a delayed coker together with other conventional raw materials, then separate coker products, wherein the coker wax oil is completely circulated to the residuum hydrotreater. The method can produce low sulfur petroleum coke. However, fixed beds have severe limitations on asphaltenes, metal content, etc. of the feed. CN201110322478.2 discloses a combined process for hydrotreating and delayed coking of residuum. The method adopts the boiling bed hydrotreating process for the residuum hydrotreating, and comprises the steps that liquid phase products of the residuum raw materials after the boiling bed hydrotreating are directly fed into a coking fractionating tower without fractionation, are in countercurrent contact with oil gas generated by coking, leach coke powder carried in the high-temperature oil gas, discharge light components generated by hydrogenation and light components generated by coking out of the device together, and recycle fractions above wax oil to a delayed coking device. The method combines boiling bed residual oil hydrogenation with delayed coking, and the boiling bed residual oil hydrogenation device has few domestic industrial applications, so that the wide application of the process is limited. Therefore, the development of the residual oil hydrogenation-delayed coking combined process capable of increasing yield of high-quality low-sulfur coke has important significance for solving the problem of high-sulfur coke outlet, improving the resource utilization rate and meeting the market demand. Disclosure of Invention The invention aims to overcome the technical problems and provide a method for increasing yield of high-quality low-sulfur petroleum coke and a device for increasing yield of high-quality low-sulfur petroleum coke. In order to achieve the aim, the first aspect of the invention provides a method for increasing yield and quality of low-sulfur coke, which comprises the steps of carrying out hydrodesulfurization pretreatment on raw oil and a catalyst, carrying out heat treatment on the obtained liquid-solid component I, carrying out separation and extraction on the obtained liquid-solid component II, and carrying out coking treatment on the obtained coking ra