Methods for processing heavy oil

Abstract

The present invention relates to the technical field of low-quality heavy oil processing, and discloses a method for processing heavy oil. The method includes: subjecting a heavy oil raw material to atmospheric distillation to obtain atmospheric distillate oil and atmospheric residue; subjecting the atmospheric residue to countercurrent contact with a solvent for extraction and separation to obtain a light component and a heavy component; the temperature of the extraction and separation is higher than the critical temperature of the solvent, and the pressure of the extraction and separation is higher than the critical pressure of the solvent; subjecting the light component to vacuum distillation, and obtaining a vacuum component I with a carbon residue value of less than 0.45w% as a hydrogenation raw material; a vacuum component II with a carbon residue value of 0.45-2.0w% as a lubricating oil raw material; and a vacuum component III with a carbon residue value greater than 2.0w% as a catalytic cracking raw material. The method can obtain a light component with a lower carbon residue value and a higher yield, and the components obtained by its graded utilization can be used as high-quality hydrogenation raw materials, lubricating oil raw materials and catalytic cracking raw materials, and the heavy component is used as an additive for hard asphalt, with excellent economic benefits.

Description

Technical Field

[0001] The present invention relates to the technical field of low-quality heavy oil processing, and in particular to a method for processing heavy oil. Background Art

[0002] Since the 21st century, conventional oil resources worldwide have been declining, with the trend toward heavier and lower-quality oil resources. With advancements in crude oil extraction technology and the continuous increase in heavy oil production, increasingly stringent environmental regulations and growing demand for lighter oil products have drawn the attention of major oil companies worldwide regarding the efficient conversion and comprehensive utilization of heavy oil. Heavy oil accounts for a significant proportion of petroleum resources, with its total equivalent reserves far exceeding those of conventional crude oil and natural gas. In recent years, global production and processing of heavy oil has continued to grow. The sustainable, efficient, and economical utilization of heavy oil resources, while reducing crude oil costs, can effectively improve refinery economics.

[0003] Heavy oil has the characteristics of high density, high carbon residue value, high content of colloid and asphaltene, and high metal content. It is difficult to lighten it and it is difficult to process it using conventional petroleum resource processing technology. There are two difficulties in the process of lightening heavy oil: (1) The high carbon residue value of the residual oil is prone to condensation and coking; (2) The presence of a large amount of metals such as nickel and vanadium and asphaltene can easily cause coking, metal aggregation, and a reduction in the number of active centers, ultimately leading to catalyst deactivation. It is difficult to directly use conventional fixed-bed residual oil hydrogenation units for processing, and the unit operation cycle is short. The economic benefits of processing through technical routes such as viscosity reduction and coking processes are low. The processing of heavy oil (especially low-quality heavy oil) is somewhat difficult. The degree of coking tendency in the vacuum furnace is closely related to the oil temperature and its residence time in the heating furnace tube. For a given heavy and low-quality oil, a higher furnace outlet temperature is required when using vacuum deep drawing. In order to reduce the thermal cracking reaction of the residual oil and reduce the risk of coking in the furnace tube, the branch temperature of the vacuum line of some vacuum devices is mostly below 385℃, making deep drawing difficult. When oil temperature exceeds a certain limit, thermal cracking easily occurs, producing free carbon. This leads to coking of the furnace tubes, making it difficult for the decompression system to achieve stable operation over a long period of time. This also results in unclear separation of the wax oil fraction and low yield. The residual oil obtained after distillation may meet the penetration requirements of heavy-duty road asphalt products. However, due to its low elongation, low flash point, high post-TFOT losses, and a penetration ratio that does not meet product quality requirements, it is difficult to ship as a high-grade asphalt product. Overall economic benefits are low, and a single oil processing route and product structure will no longer meet the new market demand. Therefore, for heavy crude oil, research is underway to directly post-process the atmospheric residue, avoiding high-temperature cracking while achieving high-value utilization. Bright stock is a high-viscosity base oil produced by distillation or separation of heavy oil. It boasts high added value, widespread daily use, and broad market prospects. In lubricant production, C3 is often used as a solvent to separate residual oil to obtain a bright stock feedstock that meets the requirements. However, research has found that even with C3 as a solvent for extraction of atmospheric residue oil with high viscosity and high carbon residue, the resulting light deasphalted oil cannot be directly used due to its viscosity and flash point values failing to meet the requirements for bright stock feedstock.

[0004] CN101050383A discloses a combined heavy oil processing process. Vacuum residue is treated with a butane deasphalting process to obtain two components: deasphalted oil and deoiled asphalt. The deasphalted oil is mixed with one or both of other catalytic cracking feedstocks, atmospheric residue and vacuum wax oil, and used as a feedstock for a catalytic cracking unit. High-value-added light hydrocarbons and gasoline and diesel are produced through the catalytic cracking process. The remaining catalytic cracking oil slurry, which is difficult to crack, is used as a feedstock for a slurry topping process, i.e., a vacuum fractionation process. After treatment through the vacuum fractionation process, it is separated into two components: light oil slurry and topped heavy oil slurry. The light oil slurry is mixed with a portion of the deoiled hard asphalt produced by the solvent deasphalting unit and used as a feedstock for a visbreaking unit to produce No. 7 commercial fuel oil. The topped heavy oil slurry and another portion of the deoiled hard asphalt produced by the solvent deasphalting unit are fed into an online asphalt blending unit, i.e., a static mixer, and are fully mixed to produce high-grade road petroleum asphalt. When this method processes inferior and heavy crude oil, the vacuum distillation unit fluctuates greatly due to its easy cracking, resulting in unstable operation, high energy consumption, and easy corrosion of equipment by high-temperature sulfur and high-temperature acid, which shortens the start-up period of the unit and increases operating costs.

[0005] Furthermore, in the prior art, after using solvents to separate atmospheric residue, the resulting light deasphalted oil is directly fed into a hydrogenation unit or a catalytic unit. However, when this method is used to treat atmospheric residue with high viscosity and high carbon residue, the resulting solvent-refined oil often does not meet the flash point requirements and is difficult to use directly as a raw material for bright stock production.

[0006] Efficiently converting and utilizing low-quality residual oil is crucial for improving a refinery's overall profitability. Existing technologies for processing low-quality heavy oil primarily rely on a simple combination of several processes, without tailored refinement based on the specific characteristics of the components. Given the high density, colloid, and asphaltene content of heavy oil, appropriate processing technologies and routes need to be developed to reduce production costs and maximize the value of the crude oil. To this end, refining companies must continuously enrich their process pipelines, leveraging the strengths of existing processing technologies to address their weaknesses and focusing on combining them to optimize the refinery's crude oil processing routes while minimizing investment costs. Summary of the Invention

[0007] The purpose of the present invention is to overcome the problems that the existing heavy oil processing methods are not suitable for processing high-viscosity and high-carbon residual heavy oil, the obtained light deasphalted oil is difficult to meet the requirements of directly being used as a raw material for the production of high-value-added lubricating oil, and the hydrogenation unit has a short operating cycle.

[0008] In order to achieve the above object, the present invention provides a method for processing heavy oil, the method comprising:

[0009] (1) subjecting a heavy oil raw material to atmospheric distillation to obtain atmospheric distillate oil and atmospheric residue oil; the heavy oil raw material has a density of greater than 0.92 g / cm at 20°C. 3 And the carbon residue value is greater than 6w%;

[0010] (2) extracting and separating the atmospheric residue oil by countercurrent contact with a solvent to obtain a light component and a heavy component; wherein the temperature of the extraction and separation is higher than the critical temperature of the solvent, and the pressure of the extraction and separation is higher than the critical pressure of the solvent; and the heavy component is used as an additive for hard asphalt;

[0011] (3) subjecting the light component to vacuum distillation to obtain vacuum component I, vacuum component II, and vacuum component III; wherein the vacuum component I has a carbon residue value of less than 0.45w%, and is used as a hydrogenation feedstock; the vacuum component II has a carbon residue value of 0.45-2.0w%, and is used as a lubricating oil feedstock; and the vacuum component III has a carbon residue value of greater than 2.0w%, and is used as a catalytic cracking feedstock.

[0012] Through the above technical solution, the method provided by the present invention processes heavy oil raw materials with high viscosity and high carbon residue. By supercritical solvent separation, the problem of easy cracking of components and low extraction rate at high temperature in the process of vacuum deep extraction of inferior heavy oil is avoided, and light components with lower carbon residue value and higher yield than those separated by subcritical solvent are obtained. The light components obtained by extraction and separation of atmospheric residue oil are separated and graded by combining supercritical solvent separation and vacuum distillation. High-quality hydrogenation raw materials, lubricating oil raw materials and catalytic cracking raw materials are respectively sent to each device, so that each device is converted under its own optimized process conditions, thereby improving the operating cycle of downstream devices and significantly improving the yield of light oil. The heavy components obtained by extraction and separation of atmospheric residue oil can be used as additives for hard asphalt to improve rutting caused by insufficient high-temperature stability of asphalt concrete pavement, improve the high-temperature deformation resistance and fatigue resistance of asphalt concrete pavement, and have excellent economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The figure is a flow chart of a method for processing heavy oil according to one embodiment of the present invention.

[0014] Description of Reference Numerals

[0015] 1. Heavy oil feedstock 2. Atmospheric distillation unit 3. Gas

[0016] 4. Atmospheric distillate oil 5. Atmospheric residue oil 6. Extraction separation unit

[0017] 7. Light components 8. Vacuum distillation unit 9. Heavy components

[0018] 10. Decompression component I 11. Decompression component II 12. Decompression component III

[0019] 13. Hydroprocessing unit 14. Lubricating oil refining unit 15. Catalytic cracking unit

[0020] 16. Blending tank 17. Hard asphalt 18. Hydrorefined oil

[0021] 19. Bright oil 20. Catalytic cracking products DETAILED DESCRIPTION

[0022] The endpoints of the ranges and any values disclosed herein are not limited to the precise ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0023] The present invention provides a method for processing heavy oil, comprising:

[0024] (1) subjecting a heavy oil raw material to atmospheric distillation to obtain atmospheric distillate oil and atmospheric residue oil; the heavy oil raw material has a density of greater than 0.92 g / cm at 20°C. 3 And the carbon residue value is greater than 6w%;

[0025] (2) extracting and separating the atmospheric residue oil by countercurrent contact with a solvent to obtain a light component and a heavy component; wherein the temperature of the extraction and separation is higher than the critical temperature of the solvent, and the pressure of the extraction and separation is higher than the critical pressure of the solvent; and the heavy component is used as an additive for hard asphalt;

[0026] (3) subjecting the light component to vacuum distillation to obtain vacuum component I, vacuum component II, and vacuum component III; wherein the vacuum component I has a carbon residue value of less than 0.45w%, and is used as a hydrogenation feedstock; the vacuum component II has a carbon residue value of 0.45-2.0w%, and is used as a lubricating oil feedstock; and the vacuum component III has a carbon residue value of greater than 2.0w%, and is used as a catalytic cracking feedstock.

[0027] According to some embodiments of the present invention, in step (1), the density of the heavy oil feedstock at 20°C is greater than 0.92 g / cm 3 The carbon residue value is greater than 6w%, which is a low-quality heavy oil with high viscosity and high carbon residue. There is no particular restriction on the source of the heavy oil raw material, which can be a low-quality heavy crude oil that meets the above requirements.

[0028] According to some embodiments of the present invention, preferably, in step (1), the heavy oil feedstock is distilled in an atmospheric distillation unit, the cut-off temperature of the atmospheric distillation is 350°C, and an atmospheric residue with a temperature greater than 350°C is obtained at the bottom of the atmospheric distillation tower (i.e., the atmospheric residue is the fraction with a temperature greater than 350°C). Because heavy oil feedstock undergoes significant decomposition starting at 350°C under atmospheric pressure, the fraction with a boiling point greater than 350°C is typically distilled under reduced pressure.

[0029] According to some embodiments of the present invention, preferably, in step (1), the viscosity of the atmospheric residue at 100°C is greater than 280 mm2 / s and the carbon residue value is not less than 13w%; more preferably, the viscosity of the atmospheric residue at 100°C is 320-5500 mm2 / s. 2 / s and the carbon residue value is 15-18w%. The viscosity and carbon residue value of the atmospheric residue oil are also high.

[0030] According to some embodiments of the present invention, preferably, the atmospheric residue has a density at 20°C greater than 0.95 g / cm 3 .

[0031] According to some embodiments of the present invention, preferably, in step (1), the atmospheric residue has a nickel content of 20-130 mg / kg; a vanadium content of 1-380 mg / kg; a nitrogen content of 0.4-1.1 w%; and a sulfur content of 0.3-3.5 w%.

[0032] According to some embodiments of the present invention, preferably, in step (1), the product of the atmospheric distillation further includes a gas component.

[0033] According to some embodiments of the present invention, preferably, in step (2), the conditions for the extraction and separation include: a temperature of 110-175° C. and a pressure of 7.5-12 MPa.

[0034] According to some embodiments of the present invention, preferably, the extractive separation is carried out in an extraction tower, and the bottom temperature of the extraction tower is 110-165° C., and the top temperature of the extraction tower is 115-175° C.;

[0035] More preferably, the bottom temperature of the extraction tower is lower than the top temperature.

[0036] According to some embodiments of the present invention, preferably, in step (2), the volume ratio of the solvent to the atmospheric residue is 6-12:1.

[0037] According to some embodiments of the present invention, preferably, in step (2), the solvent is selected from at least one of C3-C4 alkanes, preferably propane and / or isobutane.

[0038] According to some embodiments of the present invention, preferably, in step (2), the distillation range of the light component is 345-737°C.

[0039] According to some embodiments of the present invention, preferably, in step (2), the yield of the light component is 15-60%.

[0040] According to some embodiments of the present invention, preferably, in step (2), the carbon residue value of the light component is 0.2-5.5w%; the viscosity at 100°C is 15-80mm 2 / s.

[0041] According to some embodiments of the present invention, the method uses supercritical solvent separation to avoid the problem of easy cracking of components at high temperatures and low extraction rate of inferior heavy oil during vacuum deep extraction, and can obtain light components with lower residual carbon value and higher yield than subcritical solvent separation.

[0042] According to some embodiments of the present invention, preferably, in step (2), the softening point of the heavy component is 65-125°C.

[0043] According to some embodiments of the present invention, preferably, the yield of the heavy component is 40-85%.

[0044] According to some embodiments of the present invention, preferably, the density of the heavy component at 20°C is 0.99-1.07 g / cm 3 The residual carbon value is 20-30w%. The heavy component can be used as an additive for hard asphalt to prepare hard asphalt.

[0045] According to some embodiments of the present invention, preferably, in step (3), the temperature of the reduced pressure distillation is 370-580°C.

[0046] According to some embodiments of the present invention, preferably, in step (3), the first cutting temperature of the decompression component I and the decompression component II is 370-460°C; the second cutting temperature of the decompression component II and the decompression component III is 420-580°C, and the first cutting temperature is lower than the second cutting temperature; the decompression component I is a fraction having a temperature lower than the first cutting temperature, the decompression component II is a fraction having a temperature between the first cutting temperature and the second cutting temperature, and the decompression component III is a fraction having a temperature higher than the second cutting temperature.

[0047] According to some embodiments of the present invention, preferably, in step (3), the viscosity of the decompression component I at 100°C is 10-50 mm 2 / s; the total content of nickel and vanadium is less than 5 mg / kg. The decompression component I can be used as a hydrogenation feedstock for a hydrogenation reaction. Preferably, the reaction conditions include: a hydrogen partial pressure of 10-17 MPa and a temperature of 350-400°C.

[0048] According to some embodiments of the present invention, preferably, in step (3), the viscosity of the decompression component II at 100°C is 25-150 mm 2 / s; and / or, the flash point of the vacuum fraction II is greater than 280°C, which can meet the raw material requirements for producing bright stock. The vacuum fraction II can be directly used as a lubricating oil raw material for solvent extraction, solvent dewaxing, and adsorption refining by adsorbent. Preferably, the reaction conditions include: a mass ratio of extraction solvent to deasphalted oil in the solvent extraction of 3.0-6:1; an extraction tower top temperature of 90-130°C and an extraction tower bottom temperature of 50-70°C; a solvent dewaxing filtration temperature of -25 to -20°C; and adsorption refining conditions include a contact temperature of 120-210°C and a contact time of 25-50 minutes.

[0049] According to some embodiments of the present invention, preferably, in step (3), the viscosity of the decompression component III at 100°C is 90-210 mm 2 / s. The vacuum component III can be used as a catalytic cracking raw material for catalytic cracking reaction. Preferably, the reaction conditions include: reaction temperature of 490-650 ° C, catalyst-oil mass ratio of 5-55:1, mass space velocity of 4h -1 .

[0050] In the prior art, even with C3 as the solvent for extraction of high-viscosity, high-carbon-residue atmospheric residue, the resulting light deasphalted oil cannot be directly utilized due to its viscosity and flash point, which make it difficult to meet the requirements of bright stock feedstock. However, the inventors of the present invention discovered that supercritical solvent separation avoids the problems of component cracking and low extraction efficiency at high temperatures that occur during vacuum deep extraction of inferior heavy oil, thereby obtaining light fractions with lower carbon residues and higher yields than those obtained with subcritical solvent separation. By combining supercritical solvent separation with vacuum distillation, the light fractions obtained from the atmospheric residue extraction are separated and graded for utilization. High-quality hydrogenation feedstock, lubricant feedstock, and catalytic cracking feedstock are fed to separate units, allowing each unit to perform conversion under its own optimized process conditions. This improves the operating cycle of downstream units and significantly increases the yield of light oil. The heavy fractions obtained from the atmospheric residue extraction are used as additives for hard asphalt. The production cost of using these heavy fractions to improve the rutting resistance of asphalt concrete pavements is far lower than that of polymer-modified asphalt and anti-rutting additives, resulting in excellent economic benefits.

[0051] According to a particularly preferred embodiment of the present invention, the method for processing heavy oil comprises:

[0052] (1) subjecting a heavy oil raw material to atmospheric distillation to obtain atmospheric distillate oil and atmospheric residue oil; the heavy oil raw material has a density of greater than 0.92 g / cm at 20°C. 3 The carbon residue value is greater than 6w%; the viscosity of the atmospheric residue oil at 100°C is greater than 280mm 2 / s and the residual carbon value is not less than 13w%;

[0053] (2) contacting the atmospheric residue with a solvent in countercurrent flow to perform extraction and separation to obtain a light component and a heavy component; the heavy component is used as an additive for hard asphalt;

[0054] The extraction separation is carried out in an extraction tower, and the bottom temperature of the extraction tower is 110-165° C., and the top temperature of the extraction tower is 115-175° C.; the bottom temperature of the extraction tower is lower than the top temperature; the pressure of the extraction separation is 7.5-12 MPa; the volume ratio of the solvent to the atmospheric residue is 6-12:1; and the solvent is selected from at least one of C3-C4 alkanes;

[0055] (3) subjecting the light component to vacuum distillation to obtain vacuum component I, vacuum component II, and vacuum component III;

[0056] The vacuum distillation temperature is 370-580°C; the vacuum component I has a carbon residue value of less than 0.45w%, and is used as a hydrogenation feedstock; the vacuum component II has a carbon residue value of 0.45-2.0w%, and is used as a lubricating oil feedstock; and the vacuum component III has a carbon residue value greater than 2.0w%, and is used as a catalytic cracking feedstock.

[0057] The method for processing heavy oil provided by the present invention is further described in detail below with reference to the accompanying drawings.

[0058] The present invention illustratively provides a flow chart of a method for processing heavy oil according to an embodiment of the present invention, as shown in FIG. Figure 1 As shown, the method includes:

[0059] (1) In the atmospheric distillation unit 2, a heavy oil feedstock 1 is subjected to atmospheric distillation to obtain gas 3, atmospheric distillate oil 4, and atmospheric residue oil 5;

[0060] (2) In the extraction tower of the extraction and separation unit 6, the atmospheric residue 5 is brought into countercurrent contact with the solvent from the extraction and separation unit 6 to perform extraction and separation, thereby obtaining a light component 7 and a heavy component 9; the heavy component 9 is transported to the blending tank 16 as an additive for the hard asphalt 17 to prepare the hard asphalt 17;

[0061] (3) in a vacuum distillation unit 8, the light component 7 is subjected to vacuum distillation to obtain a vacuum component I 10, a vacuum component II 11, and a vacuum component III 12;

[0062] The reduced pressure component I10 is transported as a hydrogenation feedstock to a hydroprocessing unit 13 for a hydroprocessing reaction to obtain a hydrorefined oil 18;

[0063] The reduced pressure component II 11 is transported as a lubricating oil raw material to the lubricating oil refining unit 14 for solvent refining reaction to obtain bright stock 19;

[0064] The vacuum fraction III 12 is transported as a catalytic cracking feedstock to a catalytic cracking unit 15 for catalytic cracking reaction to obtain a catalytic cracking product 20.

[0065] The raw materials and operating conditions of each step can be selected by referring to the above and will not be described in detail here.

[0066] The present invention will be described in detail below through examples.

[0067] In the following examples and comparative examples, unless otherwise specified, all raw materials used are commercially available.

[0068] The heavy oil raw material used was from China National Petroleum Corporation. The density of heavy oil raw material A at 20°C was 0.921 g / cm 3 , the residual carbon value is 7.0w%; the density of heavy oil feedstock B at 20℃ is 0.924g / cm 3 , the residual carbon value is 6.7w%.

[0069] Example 1

[0070] (1) The heavy oil raw material A is subjected to atmospheric distillation to obtain atmospheric distillate oil and atmospheric residue oil; wherein:

[0071] The cut-off temperature for atmospheric distillation is 350°C. The atmospheric residue is the fraction with a temperature greater than 350°C. Its properties are shown in Table 1.

[0072] (2) The atmospheric residue oil is contacted with a solvent in a countercurrent manner in an extraction tower for extraction and separation to obtain light components and heavy components; wherein:

[0073] The volume ratio of solvent to atmospheric residue was 10:1; the solvent was propane (purity > 99%); the bottom temperature of the extraction column was 115°C, and the top temperature of the extraction column was 125°C; the extraction separation pressure was 12 MPa;

[0074] The distillation range of the light component is 347-718°C; the yield and properties of the light component are shown in Table 2; the yield and properties of the heavy component are shown in Table 3; the heavy component is used as an additive for hard asphalt, and the properties of the hard asphalt obtained by blending it with 90# asphalt are shown in Table 5;

[0075] (3) subjecting the light component to vacuum distillation to obtain vacuum component I, vacuum component II, and vacuum component III; wherein:

[0076] The cut temperature of vacuum distillation, the distillation range and properties of each component are shown in Table 4; vacuum component I is used as a hydrogenation feedstock; vacuum component II is used as a lubricating oil feedstock; and vacuum component III is used as a catalytic cracking feedstock.

[0077] Comparative Example 1

[0078] Step (1) and step (2) were carried out according to the method of Example 1, except that in step (2), the extraction separation was carried out under subcritical conditions, the bottom temperature of the extraction tower was 75°C, and the top temperature of the extraction tower was 85°C; the pressure of the extraction separation was 4 MPa; and the rest was the same as in Example 1, to obtain light components and heavy components; the yield and properties of the light components are shown in Table 2.

[0079] Comparative Example 2

[0080] The method of Example 1 is followed, except that step (3) is not performed.

[0081] Example 2

[0082] The method of Example 1 is followed, except that:

[0083] In step (1), heavy oil feedstock A is replaced by heavy oil feedstock B, and the properties of the obtained atmospheric residue are shown in Table 1;

[0084] In step (2), the volume ratio of the solvent to the atmospheric residue is 7:1; the solvent is isobutane (purity>99%); the bottom temperature of the extraction tower is 165° C., the top temperature of the extraction tower is 175° C.; the pressure of the extraction separation is 9.2 MPa;

[0085] The distillation range of the light component is 347-719°C; the yield and properties of the light component are shown in Table 2; the yield and properties of the heavy component are shown in Table 3, and the properties of the hard asphalt obtained by blending it with 90# asphalt are shown in Table 5;

[0086] In step (3), the cut temperature of the vacuum distillation, the distillation range and properties of each component are shown in Table 4;

[0087] The rest are the same as in Example 1.

[0088] Table 1 (Properties of atmospheric residue)

[0089]

[0090]

[0091] Table 2 (Light component properties)

[0092] Analysis Project Analytical methods Example 1 Example 2 Comparative Example 1 Light component yield / % / 45.3 55.0 42.3 Residual carbon / w% GB / T 17144 1.07 3.03 1.35 <![CDATA[Viscosity (80 °C) / (mm 2 / s)]]> GB / T 11137 171.90 214.1 165.3 <![CDATA[Viscosity (100 °C) / (mm 2 / s)]]> GB / T 11137 56.43 79.72 54.5 Flash point / ℃ GB / T 3536 257 264 245 C7 insoluble matter / (mg / kg) C7_INSOL_M ＜50 ＜50 ＜50 Ni+V content / (mg / kg) GB / T 37160 1.8 2.58 3.7

[0093] Table 3 (Heavy Component Properties)

[0094]

[0095] Table 4 (Properties of components obtained by vacuum distillation)

[0096]

[0097]

[0098] Table 5 (Hard Asphalt Properties)

[0099] project Example 1 Example 2 Needle penetration (25℃, 100g, 5s) / (0.1mm) 35 31 Softening point (ring and ball method) / ℃ 64 66 Brittle point / ℃ -14 -12 PG rating PG76-22 PG82-16

[0100] The above results show that the method provided by the present invention can be used to process high-viscosity, high-carbon heavy oil feedstock, resulting in a light fraction with a lower carbon residue and higher yield than that obtained by subcritical solvent separation. Furthermore, the light fraction can be separated by vacuum distillation, enabling its graded utilization. In particular, a vacuum fraction II with a carbon residue of 0.45-2.0 w% can be obtained, which can meet the requirements for direct use as a feedstock for the production of high-value-added lubricating oils. The low carbon residue and metal content of the vacuum fraction I can be fed into the hydrogenation unit, thereby improving the operating cycle of the hydrogenation unit.

[0101] Comparing the methods of Example 1 and Comparative Example 1, it can be seen that the method provided by the present invention can obtain light components with lower carbon residue value and higher yield than that of subcritical solvent separation;

[0102] Comparing the methods of Example 1 and Comparative Example 2, it can be seen that the flash point of the light component is less than 280°C. If vacuum distillation is not performed, it is not suitable to be directly used as a raw material for producing bright oil.

[0103] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A method for processing heavy oil, characterized in that: The method comprises: (1) Distilling a heavy oil feedstock under atmospheric pressure to obtain atmospheric distillate oil and atmospheric residue oil; the heavy oil feedstock has a density of greater than 0.92 g / cm at 20°C. 3 And the residual carbon value is greater than 6w; (2) extracting and separating the atmospheric residue oil by countercurrent contact with a solvent to obtain a light component and a heavy component; wherein the temperature of the extraction and separation is higher than the critical temperature of the solvent, and the pressure of the extraction and separation is higher than the critical pressure of the solvent; and the heavy component is used as an additive for hard asphalt; (3) subjecting the light fraction to vacuum distillation to obtain vacuum fraction I, vacuum fraction II, and vacuum fraction III; wherein the vacuum fraction I has a carbon residue value of less than 0.45w%, and is used as a hydrogenation feedstock; the vacuum fraction II has a carbon residue value of 0.45-2.0w%, and is used as a lubricating oil feedstock; and the vacuum fraction III has a carbon residue value of greater than 2.0w%, and is used as a catalytic cracking feedstock; The viscosity of the atmospheric residue at 100°C is 3895-5500 mm 2 / s and the residual carbon value is not less than 13w; The extraction separation is carried out in an extraction tower, and the bottom temperature of the extraction tower is 110-165° C., and the top temperature of the extraction tower is 115-175° C.; the bottom temperature of the extraction tower is lower than the top temperature.

2. The method according to claim 1, wherein In step (1), the atmospheric residue is a fraction having a temperature greater than 350° C.; and / or the product of the atmospheric distillation further includes a gas component.

3. The method according to claim 1, wherein In step (1), the carbon residue value of the atmospheric residue is 15-18% by weight; And / or, the atmospheric residue has a density of greater than 0.95 g / cm2 at 20°C. 3 .

4. The method according to any one of claims 1 to 3, wherein: In step (1), the atmospheric residue has a nickel content of 20-130 mg / kg, a vanadium content of 1-380 mg / kg, a nitrogen content of 0.4-1.1w% and a sulfur content of 0.3-3.5w%.

5. The method according to any one of claims 1 to 3, wherein: In step (2), the conditions for the extraction and separation include: a pressure of 7.5-12 MPa.

6. The method according to any one of claims 1 to 3, wherein: In step (2), the volume ratio of the solvent to the atmospheric residue is 6-12:1; And / or, the solvent is selected from at least one of C3-C4 alkanes.

7. The method according to claim 6, wherein: In step (2), the solvent is propane and / or isobutane.

8. The method according to any one of claims 1 to 3, wherein: In step (2), the distillation range of the light component is 345-737°C; the yield of the light component is 15-60%; And / or, the carbon residue value of the light component is 0.2-5.5w%; the viscosity at 100℃ is 15-80mm 2 / s.

9. The method according to any one of claims 1 to 3, wherein: In step (2), the softening point of the heavy component is 65-125° C.; the yield of the heavy component is 40-85%; And / or, the density of the heavy component at 20°C is 0.99-1.07 g / cm 3 ; The residual carbon value is 20-30w%.

10. The method according to any one of claims 1 to 3, wherein: In step (3), the temperature of the reduced pressure distillation is 370-580°C; And / or, the first cutting temperature of the decompression component I and the decompression component II is 370-460° C.; the second cutting temperature of the decompression component II and the decompression component III is 420-580° C., and the first cutting temperature is lower than the second cutting temperature; The decompression component I is a fraction having a temperature lower than the first cutting temperature, the decompression component II is a fraction having a temperature between the first cutting temperature and the second cutting temperature, and the decompression component III is a fraction having a temperature higher than the second cutting temperature.

11. The method according to any one of claims 1 to 3, wherein: In step (3), the viscosity of the decompression component I at 100°C is 10-50 mm 2 / s; the total content of nickel and vanadium is less than 5 mg / kg; And / or, the viscosity of the decompression component II at 100°C is 25-150 mm 2 / s; flash point greater than 280℃; And / or, the viscosity of the decompression component III at 100°C is 90-210 mm 2 / s.

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