Methods and apparatus for enriching aromatic components

Abstract

This invention relates to the field of petroleum component processing for high-aromatic oils, specifically a method and apparatus for enriching aromatic components. The former comprises the following steps: First, the feedstock oil, after primary adsorption refining, enters a multi-stage centrifugal extractor. In the multi-stage centrifugal extractor, the extraction solvent flows counter-currently with the feedstock oil for solvent extraction, yielding raffinate and extracted oil. Second, the extracted oil undergoes sedimentation separation to obtain upper and lower extracted oils. Third, the lower extracted oil undergoes sequential solvent separation and secondary adsorption refining to complete the enrichment and separation of high-aromatic oils from the feedstock oil, resulting in high-aromatic environmentally friendly rubber oil. This invention can simultaneously achieve both oil yield and aromatic selectivity, obtaining aromatic-rich components with an aromatic content greater than 75% and an aromatic extraction rate higher than 60%, ultimately yielding C... A It is a high-aromatic environmentally friendly rubber oil with 20% to 30% aromatics, which further improves the utilization rate of mono- and bi-cyclic aromatics in vacuum distillate oil, can achieve continuous operation, and has high refining efficiency and high recovery rate.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of processing high-aromatic oil from petroleum components, and is a method and device for enriching aromatic components. BACKGROUND

[0002] High-aromatic environment-friendly rubber oil TDAE is widely used in oil-extended rubber and tire industries due to high aromatic content, good compatibility with rubber, and advantages in improving tire processing and use performance indexes, and is mainly obtained by enrichment separation of raw oil. However, due to high dependence on imports and high oil prices, domestic high-C A The market gap of environment-friendly rubber oil is large, and the production of high-end environment-friendly tires in China is limited. The aromatic content in naphthenic base vacuum distillate oil is high, and it is a relatively suitable raw material for producing high-aromatic oil, but the content of polycyclic aromatic hydrocarbons such as tetra-, penta- and hexa-cyclic aromatic hydrocarbons in the naphthenic base vacuum distillate oil is also high, which is not conducive to the separation and enrichment of high-quality mono- and di-cyclic aromatic hydrocarbons. How to fully utilize the naphthenic base raw material resources and develop high-C A The environment-friendly naphthenic base rubber oil technology is the development direction in the field.

[0003] At present, the production technology of environmentally friendly naphthenic high aromatic oil mainly has three processes of solvent extraction, hydrogenation treatment and solvent extraction-hydrogenation treatment. However, the production method of high aromatic environmentally friendly rubber oil which is more popular at home and abroad is mostly the tower type solvent extraction method. The patent documents with publication numbers CN101591453B, CN104293385B, CN101591453B, EP-A-417980, WO9844075, USP6248929 select polar solvents such as furfural / phenol / NMP / dimethyl sulfoxide, and carry out multiple countercurrent extraction with the raw material to produce environmentally friendly aromatic oil. The Chinese patent documents with publication numbers CN101597513 and CN101386687A take reduced three-line fraction oil as raw material to carry out 2 times of solvent extraction to obtain aromatic rubber oil, and if necessary, white clay refining is used to control the content of PCA and other impurities. The Chinese patent documents with publication numbers CN101684185 and CN101928595A use cyclohexane / petroleum ether / HVI150 / elemental hydrocarbon / light hydrocarbon as dilution solvent, and use furfural / dimethyl sulfoxide to selectively remove PCA in the extracted oil under specific conditions, and if necessary, the environmentally friendly aromatic oil is obtained after white clay refining. The Chinese patent document with publication number CN1570037A uses catalytic cracking cycle oil with a residue mixing amount of 20% as raw material, and uses the extracted liquid of the lubricating oil furfural refining device as solvent to extract to obtain high aromatic oil. The Chinese patent document with publication number CN102115677A carries out pressurized and heated extraction of high aromatic oil and formula solvent (one or two or more of nitrobenzene, dimethylformamide, sulfolane, furfural, dimethyl sulfoxide) in an extraction tower after warming, filtering residue, high temperature distillation and formula blending, and obtains a product with an aromatic content of more than 30% and a yield of 80%. However, the simple tower type solvent extraction technology uses the method of directly extracting the vacuum distillate oil of naphthenic crude oil twice or more than twice to produce environmentally friendly aromatic rubber oil, the extraction separation efficiency is low, the mass ratio of solvent to raw material oil is large and easy to fluctuate with the properties of raw material, and the aromatic content, aromatic carbon content and yield of the obtained environmentally friendly aromatic oil are low.

[0004] In terms of hydrogenation treatment process for preparing high aromatic oil, the Chinese patent document with publication number CN102311784A carries out hydrogenation modification reaction and hydrogenation refining reaction of raw material oil and hydrogen under hydrogenation treatment conditions, and adjusts the catalyst to obtain environmentally friendly rubber oil. The Chinese patent document with publication number CN108611120A uses hydrogenation treatment-isomerization and condensation-hydrogenation refining to effectively improve the light and heat stability of naphthenic rubber oil without affecting the naphthenic content in naphthenic rubber oil, and the aromatic yield can reach 81%, and the aromatic content in the product is 50%.

[0005] Regarding the production of high-aromatic oils using solvent extraction-hydrogenation processes, Chinese patent document CN102453538A uses lubricating oil solvent-refined extract as raw material. It employs mild hydrogenation to control the saturation rate of polycyclic aromatic hydrocarbons (PAHs) between 40% and 50%, followed by shallow extraction to obtain PCA < 3.0% and C2O2 < 50%. A Environmentally friendly aromatic oils for tires with >20% aromatic content. European patent document EP1260569-A2 uses a mixture of vacuum distillate oil and solvent extract from lubricating oil solvent refining as raw materials, employing a nickel-molybdenum / nickel-cobalt type hydrorefining catalyst to produce environmentally friendly aromatic oils. Chinese patent document CN103160318 uses crude oil, atmospheric / vacuum residue, and vacuum distillate oil as raw materials, utilizing a combined process of thermal cracking-hydrorefining-solvent refining-hydrotreating to produce environmentally friendly high-aromatic oils with an aromatic content of 10% to 60%. Chinese patent document CN107987876A utilizes the residue oil after hydrorefining-vacuum stripping-solvent extraction to obtain environmentally friendly naphthenic rubber oil. Chinese patent document CN103773493A describes a method where the feedstock oil is first subjected to shallow extraction with a suitable solvent to partially remove polycyclic aromatic hydrocarbons, gums, asphaltenes, and heavy metals. Then, using a suitable hydrotreating catalyst under relatively mild hydrotreating conditions, some aromatic rings of the polycyclic aromatic hydrocarbons are opened to generate monocyclic or bicyclic aromatic hydrocarbons, yielding C64444493A. A The above-mentioned technology significantly increases the content of non-ideal components in the extracted oil after solvent extraction, increasing the difficulty of subsequent hydrotreating and affecting the catalyst's lifespan. While hydrorefining can deeply hydrogenate the solvent-refined oil, achieving PCA <3%, it also results in a significant loss of aromatics due to the limitation of chemical equilibrium, leading to a substantial loss of aromatics value. Therefore, it is impossible to simultaneously achieve both performance targets. Furthermore, hydrorefining requires stringent operating conditions, consumes a large amount of hydrogen, and incurs high operating costs.

[0006] In conclusion, existing technologies cannot obtain C. A High aromatic hydrocarbon environmentally friendly rubber oils with a content of >25% are less competitive compared to foreign high aromatic hydrocarbon environmentally friendly rubber oil products. Summary of the Invention

[0007] This invention provides a method and apparatus for enriching aromatic hydrocarbon components, overcoming the shortcomings of the prior art. It effectively solves the problem of low aromatic hydrocarbon content in the raw materials used in the production of environmentally friendly rubber oils, resulting in low-quality environmentally friendly rubber oil C. A The problem is not high.

[0008] One of the technical solutions of the present invention is achieved through the following measures: a method for enriching aromatic hydrocarbon components, comprising the following steps:

[0009] The first step involves the raw oil undergoing adsorption refining and then entering a multi-stage centrifugal extractor. In the multi-stage centrifugal extractor, the extraction solvent and the raw oil flow counter-currently to perform solvent extraction, yielding raffinate oil and extracted oil.

[0010] The second step is to separate the extracted oil by sedimentation to obtain upper extracted oil and lower extracted oil.

[0011] The third step involves sequentially solvent separation and secondary adsorption refining of the extracted oil to enrich and separate the high aromatic hydrocarbon oil from the raw material oil, thereby obtaining high aromatic hydrocarbon environmentally friendly rubber oil.

[0012] The following are further optimizations and / or improvements to one of the above-mentioned technical solutions:

[0013] The above-mentioned methods for enriching aromatic components also include:

[0014] The fourth step is to separate the raffinate obtained in the first step by sedimentation to obtain upper raffinate and lower raffinate.

[0015] The fifth step involves combining the residual oil from the bottom pump and the oil extracted from the top pump obtained in the second step, followed by solvent separation to enrich and separate low-aromatic oil from the feedstock oil, thus obtaining low-aromatic environmentally friendly rubber oil. The residual oil from the top pump is then separated by solvent to obtain catalytic cracking feedstock and lubricating oil base oil.

[0016] In the first step above, the feedstock is a naphthenic vacuum distillate or light de-oiled oil with a distillation range of 300°C to 550°C and a molecular weight of 320 to 520; the aromatic content in the feedstock is 20.0% to 27.5%, and the alkane content is not higher than 50%.

[0017] In the first step described above, the operating conditions for solvent extraction in the multi-stage centrifugal extractor are as follows: the mass ratio of extraction solvent to feed oil is 0.5:1 to 10:1, the temperature of the light phase inlet of the multi-stage centrifugal extractor is 30°C to 120°C, the temperature of the heavy phase inlet of the multi-stage centrifugal extractor is 60°C to 140°C, and the extraction pressure is 0.01 MPa to 0.1 MPa.

[0018] In the first step described above, the operating conditions for solvent extraction in the multi-stage centrifugal extractor are as follows: the mass ratio of extraction solvent to feed oil is 2:1 to 6:1, the temperature of the light phase inlet of the multi-stage centrifugal extractor is 40°C to 100°C, the temperature of the heavy phase inlet of the multi-stage centrifugal extractor is 70°C to 110°C, and the extraction pressure is 0.01MPa to 0.05MPa.

[0019] In the first step described above, the operating conditions for solvent extraction in the multi-stage centrifugal extractor are as follows: the mass ratio of extraction solvent to feed oil is 2:1 to 6:1, the temperature of the light phase inlet of the multi-stage centrifugal extractor is 40°C to 100°C, the temperature of the heavy phase inlet of the multi-stage centrifugal extractor is 70°C to 110°C, and the extraction pressure is 0.01MPa to 0.05MPa.

[0020] In the first step above, the extraction solvent is a mixture of solvents A and B, where solvent A is a strongly polar solvent and accounts for 30% to 60% of the total volume of the extraction solvent, and solvent B is a weakly polar solvent and accounts for 40% to 70% of the total volume of the extraction solvent.

[0021] In the first step above, the operating conditions for the single adsorption purification are as follows: the adsorbent is clay, the amount of adsorbent is 5% to 20% of the mass of the raw oil, the reaction temperature is 60℃ to 120℃, and the reaction time is 30 min to 120 min.

[0022] In the third step above, the operating conditions for secondary adsorption purification are as follows: the adsorbent is powdered activated carbon with oxygen-containing functional groups, the amount of adsorbent is 0.2% to 20% of the mass of the extracted oil, the adsorption time is 30 min to 60 min, and the adsorption temperature is 40℃ to 100℃.

[0023] In the first step above, the number of centrifugal extractor stages in the multi-stage centrifugal extractor is i, and 2≤i≤6.

[0024] In the first step above, the residence time of the feed oil and extraction solvent in the multi-stage centrifugal extractor is 30s to 120min, and the separation factor of the multi-stage centrifugal extractor is 500 to 1500.

[0025] In the second and fourth steps above, the operating conditions for sedimentation separation are: sedimentation time of 30 min to 120 min and sedimentation temperature of 30℃ to 80℃.

[0026] Solvent A is one or more of H2O, sulfolane, dimethyl sulfoxide, N-formylmorpholine, furfural, acetylfuran, N,N-dimethylacetamide, N,N-dimethylformamide, N-methylpyrrolidone, N-methylethanolamine, N-ethylmorpholine, glycerol, ethylene glycol, propylene glycol, N,N,N,N-tetramethylurea, diacetone alcohol, 1,2-dichloroethane, and ethylene glycol diethyl ether; solvent B is one or more of N-methylpyrrolidone, N-methylethanolamine, N-ethylmorpholine, glycerol, ethylene glycol, propylene glycol, N,N,N,N-tetramethylurea, diacetone alcohol, 1,2-dichloroethane, and ethylene glycol diethyl ether.

[0027] The second technical solution of the present invention is achieved through the following measures: an apparatus for implementing a method for enriching aromatic hydrocarbon components, comprising a first adsorption purifier, a multi-stage centrifugal extractor, a heavy phase settling tank, a second adsorption purifier, a heavy phase solvent remover, and a mixed solvent remover; the feed end of the first adsorption purifier is fixedly connected to a feed oil pipeline; the discharge end of the first adsorption purifier is fixedly connected to the primary light phase feed inlet of the multi-stage centrifugal extractor via a centrifugal extraction pipeline; and the final heavy phase feed inlet of the multi-stage centrifugal extractor is fixedly connected to an extraction solvent feed pipeline. An oil extraction pipeline is fixedly connected between the primary outlet of the multi-stage centrifugal extractor and the heavy phase settling tank. An upper oil extraction pipeline is fixedly connected between the first outlet of the heavy phase settling tank and the inlet of the mixing solvent remover. A low-aromatic oil pipeline is fixedly connected to the outlet of the mixing solvent remover. A heavy phase solvent removal pipeline is fixedly connected between the second outlet of the heavy phase settling tank and the inlet of the heavy phase solvent remover. A secondary adsorption and purification pipeline is fixedly connected between the outlet of the heavy phase solvent remover and the second adsorption and purification unit. A high-aromatic oil pipeline is fixedly connected to the outlet of the second adsorption and purification unit.

[0028] The apparatus for implementing the above-mentioned method for enriching aromatic components further includes a light phase settling tank and a light phase solvent remover. A main raffinate oil pipeline is fixedly connected between the final discharge port of the multi-stage centrifugal extractor and the feed end of the light phase settling tank. An upper raffinate oil pipeline is fixedly connected between the first discharge end of the light phase settling tank and the feed end of the light phase solvent remover. A non-aromatic oil pipeline is fixedly connected to the discharge end of the light phase solvent remover. A lower raffinate oil pipeline is fixedly connected between the second discharge end of the light phase settling tank and the upper extraction oil pipeline.

[0029] A mixing and solvent removal pipeline is fixedly connected between the above-mentioned main raffinate pipeline and the upper extraction pipeline between the heavy phase settling tank and the lower raffinate pipeline.

[0030] The beneficial effects of this invention are as follows:

[0031] (1) The mixed solvent used in this invention can simultaneously achieve both oil yield and aromatic selectivity compared to existing traditional solvents. By combining a multi-stage centrifugal extractor with adsorption and sedimentation processes, aromatic-rich components with an aromatic content greater than 75% and an aromatic extraction rate greater than 60% can be obtained, and C30 can be finally obtained. A It is a high-aromatic, environmentally friendly rubber oil with 20% to 30% aromatic hydrocarbon content.

[0032] (2) It improves the utilization rate of mono- and dicyclic aromatic hydrocarbons in cycloalkyl vacuum distillate.

[0033] (3) It can achieve continuous operation, high refining efficiency and high recovery rate. Attached Figure Description

[0034] Appendix Figure 1 This is a schematic diagram of the process flow of the present invention.

[0035] Appendix Figure 1The codes in the diagram are as follows: 1 for the first adsorption purifier, 2 for the multi-stage centrifugal extractor, 3 for the heavy phase settling tank, 4 for the second adsorption purifier, 5 for the heavy phase solvent remover, 6 for the mixed solvent remover, 7 for the light phase settling tank, 8 for the light phase solvent remover, 9 for the feed oil pipeline, 10 for the centrifugal extraction pipeline, 11 for the extraction solvent feed pipeline, 12 for the extracted oil pipeline, 13 for the upper extracted oil pipeline, 14 for the low aromatic oil pipeline, 15 for the heavy phase solvent remover pipeline, 16 for the secondary adsorption purifier pipeline, 17 for the high aromatic oil pipeline, 18 for the main raffinate oil pipeline, 19 for the upper raffinate oil pipeline, 20 for the non-aromatic oil pipeline, 21 for the lower raffinate oil pipeline, and 22 for the mixed solvent remover pipeline. Detailed Implementation

[0036] This invention is not limited to the following embodiments; specific implementation methods can be determined according to the technical solution of this invention and actual conditions. Unless otherwise specified, all chemical reagents and chemicals mentioned in this invention are known and commonly used chemical reagents and chemicals in the prior art. Room temperature in this invention generally refers to a temperature between 15°C and 25°C, generally defined as 25°C. Unless otherwise specified, all equipment and apparatus used in this invention are known and commonly used equipment and apparatus in the art.

[0037] The present invention will be further described below with reference to embodiments:

[0038] Example 1: As Figure 1 As shown, the method for enriching aromatic components is carried out according to the following steps:

[0039] In the first step, after the raw oil undergoes adsorption refining, it enters the multi-stage centrifugal extractor 2. In the multi-stage centrifugal extractor 2, the extraction solvent and the raw oil flow counter-currently to carry out solvent extraction, obtaining raffinate oil and extracted oil.

[0040] The second step is to separate the extracted oil by sedimentation to obtain upper extracted oil and lower extracted oil.

[0041] The third step involves sequentially solvent separation and secondary adsorption refining of the extracted oil to enrich and separate the high aromatic hydrocarbon oil from the raw material oil, thereby obtaining high aromatic hydrocarbon environmentally friendly rubber oil.

[0042] Example 2: As an optimization of the above embodiment, the method for enriching aromatic components further includes:

[0043] The fourth step is to separate the raffinate obtained in the first step by sedimentation to obtain upper raffinate and lower raffinate.

[0044] The fifth step involves combining the residual oil from the bottom pump and the oil extracted from the top pump obtained in the second step, followed by solvent separation to enrich and separate low-aromatic oil from the feedstock oil, thus obtaining low-aromatic environmentally friendly rubber oil. The residual oil from the top pump is then separated by solvent to obtain catalytic cracking feedstock and lubricating oil base oil.

[0045] Example 3: As an optimization of the above example, in the first step, the feed oil is a naphthenic vacuum distillate or light de-oiled oil with a distillation range of 300°C to 550°C and a molecular weight of 320 to 520; the aromatic content in the feed oil is 20.0% to 27.5%, and the alkane content is not higher than 50%.

[0046] Example 4: Figure 1 As shown, as an optimization of the above embodiment, in the first step, the operating conditions for solvent extraction in the multi-stage centrifugal extractor 2 are as follows: the mass ratio of extraction solvent to raw oil is 0.5:1 to 10:1, the temperature of the light phase inlet of the multi-stage centrifugal extractor 2 is 30°C to 120°C, the temperature of the heavy phase inlet of the multi-stage centrifugal extractor 2 is 60°C to 140°C, and the extraction pressure is 0.01 MPa to 0.1 MPa.

[0047] Example 5: Figure 1 As shown, as an optimization of the above embodiment, in the first step, the operating conditions for solvent extraction in the multi-stage centrifugal extractor 2 are as follows: the mass ratio of extraction solvent to raw oil is 2:1 to 6:1, the temperature of the light phase inlet of the multi-stage centrifugal extractor is 40°C to 100°C, the temperature of the heavy phase inlet of the multi-stage centrifugal extractor is 70°C to 110°C, and the extraction pressure is 0.01MPa to 0.05MPa.

[0048] Example 6: As an optimization of the above example, in the first step, the extraction solvent is a mixed solvent of A and B, wherein solvent A is a strongly polar solvent and accounts for 30% to 60% of the total volume of the extraction solvent, and solvent B is a weakly polar solvent and accounts for 40% to 70% of the total volume of the extraction solvent.

[0049] Example 7: As an optimization of Example 6 above, solvent A is one or more of H2O, sulfolane, dimethyl sulfoxide, N-formylmorpholine, furfural, acetylfuran, N,N-dimethylacetamide, N,N-dimethylformamide, N-methylpyrrolidone, N-methylethanolamine, N-ethylmorpholine, glycerol, ethylene glycol, propylene glycol, N,N,N,N-tetramethylurea, diacetone alcohol, 1,2-dichloroethane, and ethylene glycol diethyl ether; solvent B is one or more of N-methylpyrrolidone, N-methylethanolamine, N-ethylmorpholine, glycerol, ethylene glycol, propylene glycol, N,N,N,N-tetramethylurea, diacetone alcohol, 1,2-dichloroethane, and ethylene glycol diethyl ether.

[0050] Example 8: As an optimization of the above example, in the second and fourth steps, the sedimentation separation operation conditions are: sedimentation time of 30 min to 120 min and sedimentation temperature of 30°C to 80°C.

[0051] Example 9: As an optimization of the above examples, the operating conditions for the first adsorption purification in the first step are as follows: the adsorbent is kaolin, the amount of adsorbent is 5% to 20% of the mass of the feed oil, the reaction temperature is 60℃ to 120℃, and the reaction time is 30 min to 120 min. After the first adsorption purification treatment, the PCA content in the feed oil is <1%.

[0052] Example 10: As an optimization of the above examples, in the third step, the operating conditions for secondary adsorption purification are as follows: the adsorbent is powdered activated carbon with oxygen-containing functional groups, the amount of adsorbent is 0.2% to 20% of the mass of the extracted oil, the adsorption time is 30 min to 60 min, and the adsorption temperature is 40℃ to 100℃. The oxygen-containing functional groups of the powdered activated carbon can be carboxyl groups, lactone groups, and phenolic hydroxyl groups, etc.

[0053] Example 11: As an optimization of the above example, in the first step, the number of centrifugal extraction stages in the multi-stage centrifugal extractor 2 is i, and 2≤i≤6. In actual operation, the number of extraction stages can be increased or decreased according to the required oil quality.

[0054] Example 12: As Figure 1 As shown, as an optimization of the above embodiment, in the first step, the residence time of the raw oil and the extraction solvent in the multi-stage centrifugal extractor 2 is 30s to 120min, and the separation factor of the multi-stage centrifugal extractor 2 is 500 to 1500.

[0055] This invention provides a method for enriching aromatic components and producing environmentally friendly high-aromatic oils using naphthenic vacuum distillate oils with an aromatic content of 9% to 50% as raw materials, employing a combined process of adsorption refining, centrifugal solvent extraction, sedimentation separation, and adsorption refining. The solvent extraction process has advantages such as a wide range of adaptable raw materials, simple process, low investment, and good separation effect, while removing PCA and maintaining a high C content. A The extractant plays a crucial role in the effective separation of mixtures using solvent extraction technology. In the first step of this invention, the feed oil is a naphthenic vacuum distillate, light de-oiling oil, etc., with a boiling range of 300°C to 550°C, a molecular weight of 320 to 520, an aromatic hydrocarbon content of 20.0% to 27.5%, and an alkane content not exceeding 50%. The extraction solvent used in this invention is an AB mixed solvent, which fully utilizes the complementary advantages of strong and weak polar solvents. The properties of the mixed solvent can be adjusted according to production needs to adapt it to oils with different properties.

[0056] The multi-stage centrifugal extractor 2 used in this invention is composed of multiple centrifugal extractor units. A motor drives the drum to rotate at high speed. Raw material oils of different densities and immiscible with each other, along with the extraction solvent, enter the mixing zone between the drum and the shell through two separate inlets, one for light and one for heavy components, according to a specific solvent-to-raw material oil mass ratio. This allows for rapid mixing and thorough contact between the two phases, enabling the aromatic components in the raw material oil to dissolve into the extraction solvent during the extraction process, thus completing the extraction mass transfer process. The mixture of raw material oil and extraction solvent enters the drum under the action of a vortex plate. The mixture rotates synchronously with the drum. Under the action of centrifugal force, the denser, heavier phase flows upwards and gradually moves towards the center of the drum and towards the drum wall; the less dense, lighter phase gradually moves away from the drum wall and towards the center. The clarified liquids of both phases finally enter the collection chamber through their respective weirs and are led out of the machine through discharge pipes, ultimately separating into extracted oil and residual oil phases.

[0057] The entire process involves two adsorption refining treatments, both primarily based on physical adsorption. The first adsorption refining uses activated clay, mainly to adsorb non-ideal components such as macromolecules and polar substances from the feedstock oil to reduce PCA (polyacrylamide). The selected activated clay is a layered silicate crystal, obtained through acidification and drying, with a microporous network structure on its surface. During refining, non-ideal components are quickly and completely adsorbed onto the inner surface of the activated clay lattice. Under nitrogen protection, the PCA of the feedstock oil treated with activated clay is <1%. The second adsorption refining uses powdered activated carbon. Powdered activated carbon has a well-developed pore structure and a large specific surface area, and is chemically stable, acid and alkali resistant. In addition, the surface of activated carbon also has a certain proportion of oxygen-containing functional groups such as carboxyl groups, lactone groups, and phenolic hydroxyl groups. After modification with 10% to 50% HNO3, the total acidity of the activated carbon surface can reach 1 mmol / g to 2 mmol / g. These functional groups endow activated carbon with unique chemical properties, enabling it to combine with various substances and achieve an adsorption effect. After secondary adsorption refining, the extracted oil contains less than 3% PCA, less than 10 μg / g of the eight polycyclic aromatic hydrocarbons (PAHs), and less than 1 μg / g of benzo(a)pyrene, thus obtaining C A >25% high aromatic hydrocarbon environmentally friendly rubber oil.

[0058] Example 13: As Figure 1As shown, the apparatus for implementing the method of enriching aromatic components includes a first adsorption purifier 1, a multi-stage centrifugal extractor 2, a heavy phase settling tank 3, a second adsorption purifier 4, a heavy phase solvent remover 5, and a mixed solvent remover 6. The feed end of the first adsorption purifier 1 is fixedly connected to a feed oil pipeline 9. The discharge end of the first adsorption purifier 1 is fixedly connected to the primary light phase feed inlet of the multi-stage centrifugal extractor 2 via a centrifugal extraction pipeline 10. The final heavy phase feed inlet of the multi-stage centrifugal extractor 2 is fixedly connected to an extraction solvent feed pipeline 11. The primary discharge outlet of the multi-stage centrifugal extractor 2 is connected to... A pumping oil pipeline 12 is fixedly connected between the heavy phase settling tanks 3 and the first discharge end of the heavy phase settling tank 3 and the feed end of the mixing solvent remover 6. An upper pumping oil pipeline 13 is fixedly connected between the first discharge end of the heavy phase settling tank 3 and the feed end of the mixing solvent remover 6. A low aromatic oil pipeline 14 is fixedly connected between the discharge end of the heavy phase settling tank 3 and the feed end of the heavy phase solvent remover 5. A secondary adsorption and purification pipeline 16 is fixedly connected between the discharge end of the heavy phase solvent remover 5 and the second adsorption and purification unit 4. A high aromatic oil pipeline 17 is fixedly connected between the discharge end of the second adsorption and purification unit 4.

[0059] Example 14: As Figure 1 As shown, as an optimization of the above embodiment, the apparatus for implementing the method of enriching aromatic components further includes a light phase settling tank 7 and a light phase solvent remover 8. The final discharge port of the multi-stage centrifugal extractor 2 is fixedly connected to the feed end of the light phase settling tank 7 via a main raffinate oil pipeline 18. The first discharge end of the light phase settling tank 7 is fixedly connected to the feed end of the light phase solvent remover 8 via an upper raffinate oil pipeline 19. The discharge end of the light phase solvent remover 8 is fixedly connected to a non-aromatic oil pipeline 20. The second discharge end of the light phase settling tank 7 is fixedly connected to the upper extraction oil pipeline 13 via a lower raffinate oil pipeline 21.

[0060] Example 15: As Figure 1 As shown, as an optimization of the above embodiment, a mixing desolvation pipeline 22 is fixedly connected between the raffinate main pipeline 18 and the upper extraction oil pipeline 13 between the heavy phase settling tank 3 and the lower raffinate pipeline 21.

[0061] As needed, the multi-stage centrifugal extractor 2, heavy phase settling tank 3, heavy phase solvent remover 5, mixed solvent remover 6, light phase settling tank 7, and light phase solvent remover 8 in the apparatus for implementing the method of enriching aromatic components are all equipped with N2 protection during operation. The multi-stage centrifugal extractor 2 contains heat preservation or heat tracing facilities to meet the extraction temperature requirements, and valves that enable its normal operation are fixedly installed on each pipeline.

[0062] In operation, the feed oil passes through the first adsorption refiner 1 and enters through the primary light phase inlet of the multi-stage centrifugal extractor 2. The extraction solvent enters through the final heavy phase inlet of the multi-stage centrifugal extractor 2. The extraction solvent and feed oil flow counter-currently for mass transfer. The resulting raffinate and extracted oil flow out from the final light phase outlet and the primary heavy phase outlet of the multi-stage centrifugal extractor 2, respectively. The extracted oil enters the heavy phase settling tank 3, where it is separated to obtain upper and lower extracted oils. The lower extracted oil enters the heavy phase solvent remover 5 for solvent separation and then passes through the second adsorption refiner 4 for further purification, resulting in PCA <3%, aromatic content >75%, and C A The raffinate is a high-aromatic environmentally friendly rubber oil with a content of 20% to 30%. The raffinate can be directly combined with the upper extracted oil via the mixing and solvent removal line 22 and then enter the mixing and solvent removal unit 6 for solvent separation to obtain a low-aromatic environmentally friendly rubber oil. Alternatively, the raffinate can be separated into upper and lower raffinate oils in the light phase settling tank 7. The lower raffinate oil is then combined with the upper extracted oil for solvent separation to finally obtain a low-aromatic environmentally friendly rubber oil. After solvent separation, the upper raffinate oil yields a non-aromatic oil, which can be used as a catalytic cracking feedstock, lubricating oil base oil, etc.

[0063] Example 16:

[0064] like Figure 1 As shown, the feedstock oil in this embodiment is a hydrotreated naphthenic reduced-distillate oil with a molecular weight of 320, an aromatic content of 27.5%, and a distillation range of 300°C to 450°C.

[0065] The feedstock oil first enters the first adsorption refiner 1 for adsorption purification. The adsorption purification conditions are as follows: the amount of clay added to the first adsorption refiner 1 is 5% of the feedstock oil mass, the reaction temperature is 60℃, and the reaction time is 30 min. The purified feedstock oil enters through the light phase inlet of the multi-stage centrifugal extractor 2, and the extraction solvent enters through the heavy phase inlet. The volume ratio of solvent A (furfural:dimethyl sulfoxide = 1:1) to solvent B (diacetone alcohol) in the extraction solvent is 3:7. The solvent extraction operating conditions are as follows: the mass ratio of solvent to feedstock oil is 0.5:1, the light phase inlet temperature is 30℃, the heavy phase inlet temperature of the multi-stage centrifugal extractor is 60℃, the extraction pressure is 0.01 MPa, the number of extraction stages is 2, the residence time is 30 s, and the separation factor is 500; the extracted oil and the raffinate oil are separated.

[0066] The extracted oil enters the heavy phase settling tank 3, where it settles for 30 minutes at 30°C, separating the upper and lower extracted oils. The upper extracted oil and raffinate are combined and then subjected to solvent separation; the lower extracted oil undergoes solvent separation separately. The separated upper extracted oil and raffinate are combined and used as feedstock for catalytic cracking.

[0067] The separated lower-extracted oil is refined in the second adsorption refiner 4. The adsorption refining conditions are: activated carbon dosage is 0.2% of the lower-extracted oil mass, adsorption time is 30 min, and adsorption temperature is 40℃, thus obtaining C. A This is an environmentally friendly high-aromatic rubber oil with a content of 27.8%. See Table 1 for detailed parameters.

[0068] Example 17:

[0069] like Figure 1 As shown, the feedstock oil in this embodiment is a hydrotreated naphthenic subtractive third-line distillate oil with a molecular weight of 385, an aromatic content of 24.6%, and a distillation range of 350°C to 470°C.

[0070] The feedstock oil first enters the first adsorption refiner 1 for adsorption purification. The adsorption purification conditions are as follows: the amount of clay added to the first adsorption refiner 1 is 8% of the feedstock oil mass, the reaction temperature is 90℃, and the reaction time is 60 min. The purified feedstock oil enters through the light phase inlet of the multi-stage centrifugal extractor 2, and the extraction solvent enters through the heavy phase inlet. The volume ratio of solvent A (sulfolane) to solvent B (N-methylpyrrolidone) in the extraction solvent is 4:6. The solvent extraction operating conditions are as follows: the solvent to feedstock oil mass ratio is 2:1, the light phase inlet temperature is 60℃, the heavy phase inlet temperature of the multi-stage centrifugal extractor is 80℃, the extraction pressure is 0.05 MPa, the number of extraction stages is 3, the residence time is 10 min, and the separation factor is 650; the extracted oil and the raffinate oil are separated.

[0071] The extracted oil enters the heavy phase settling tank 3, and the residual oil enters the light phase settling tank 7. The settling time is 60 minutes, and the temperature is 80℃. The upper layer extracted oil, lower layer extracted oil, upper layer residual oil, and lower layer residual oil are separated. The lower layer extracted oil and the upper layer residual oil are separately subjected to solvent separation. The upper layer extracted oil and the lower layer residual oil are mixed and then subjected to solvent separation. The separated upper layer extracted oil and lower layer residual oil are combined to form a low-aromatic environmentally friendly rubber oil.

[0072] The separated lower-extracted oil is refined in a second adsorption refiner 4. The adsorption refining conditions are: activated carbon dosage is 5% of the lower-extracted oil mass, adsorption time is 50 min, and adsorption temperature is 60℃. This yields C. A This is an environmentally friendly high-aromatic rubber oil with a content of 30.9%. See Table 1 for detailed parameters.

[0073] Example 18:

[0074] like Figure 1 As shown, the feedstock oil in this embodiment is a hydrotreated naphthenic reduced-four fraction oil with a molecular weight of 410, an aromatic content of 20%, and a distillation range of 370°C to 520°C.

[0075] The feedstock oil first enters the first adsorption refiner 1 for adsorption purification. The adsorption purification conditions are as follows: the amount of clay added to the first adsorption refiner 1 is 10% of the feedstock oil mass, the reaction temperature is 110℃, and the reaction time is 100 min. The purified feedstock oil enters through the light phase inlet of the multi-stage centrifugal extractor 2, and the extraction solvent enters through the heavy phase inlet. The volume ratio of solvent A (N,N-dimethylacetamide:acetylfuran = 5:2) to solvent B (N-methylpyrrolidone) in the extraction solvent is 7:3. The solvent extraction operating conditions are as follows: the mass ratio of solvent to feedstock oil is 6:1, the light phase inlet temperature is 70℃, the heavy phase inlet temperature of the multi-stage centrifugal extractor is 110℃, the extraction pressure is 0.05 MPa, the number of extraction stages is 4, the residence time is 30 min, and the separation factor is 1000; the extracted oil and the raffinate oil are separated.

[0076] The extracted oil enters the heavy phase settling tank 3, and the residual oil enters the light phase settling tank 7. The settling time is 120 minutes, and the temperature is 60℃. The upper layer extracted oil, lower layer extracted oil, upper layer residual oil, and lower layer residual oil are separated. The lower layer extracted oil and the upper layer residual oil are separately subjected to solvent separation. The upper layer extracted oil and the lower layer residual oil are mixed and then subjected to solvent separation. The separated upper layer extracted oil and lower layer residual oil are combined to form a low-aromatic environmentally friendly rubber oil.

[0077] The separated lower-extracted oil is refined in a second adsorption refiner 4. The adsorption refining conditions are: activated carbon dosage is 5% of the lower-extracted oil mass, adsorption time is 60 min, and adsorption temperature is 60℃. This yields C. A This is an environmentally friendly high-aromatic rubber oil with a content of 31.5%. See Table 1 for detailed parameters.

[0078] Example 19:

[0079] like Figure 1 As shown, the raw material oil in this embodiment is the same as that in Example 18.

[0080] The feedstock oil first enters the first adsorption refiner 1 for adsorption purification. The adsorption purification conditions are as follows: the amount of clay added to the first adsorption refiner 1 is 10% of the feedstock oil mass, the reaction temperature is 110℃, and the reaction time is 100 min. The purified feedstock oil enters through the light phase inlet of the multi-stage centrifugal extractor 2, and the extraction solvent enters through the heavy phase inlet. The volume ratio of solvent A (N,N-propanetriol) to solvent B (N,N,N,N-tetramethylurea) in the extraction solvent is 1:1. The solvent extraction operating conditions are as follows: solvent to feedstock oil mass ratio is 3:1, light phase inlet temperature is 40℃, heavy phase inlet temperature of the multi-stage centrifugal extractor is 70℃, extraction pressure is 0.05 MPa, extraction stages are 4, residence time is 60 min, and separation factor is 1500; the extracted oil and raffinate oil are separated.

[0081] The extracted oil enters the heavy phase settling tank 3, and the residual oil enters the light phase settling tank 7. The settling time is 120 minutes, and the temperature is 60℃. The upper layer extracted oil, lower layer extracted oil, upper layer residual oil, and lower layer residual oil are separated. The lower layer extracted oil and the upper layer residual oil are separately subjected to solvent separation. The upper layer extracted oil and the lower layer residual oil are mixed and then subjected to solvent separation. The separated upper layer extracted oil and lower layer residual oil are combined to form a low-aromatic environmentally friendly rubber oil.

[0082] The separated lower-extracted oil is refined in a second adsorption refiner 4. The adsorption refining conditions are: activated carbon dosage is 5% of the lower-extracted oil mass, adsorption time is 60 min, and adsorption temperature is 60℃. This yields C. A This is an environmentally friendly high-aromatic rubber oil with a content of 28.5%. See Table 1 for detailed parameters.

[0083] Example 20:

[0084] like Figure 1 As shown, the feedstock oil in this embodiment is a naphthenic reduced-third-line distillate oil with a molecular weight of 430, an aromatic content of 23.5%, and a distillation range of 330°C to 460°C.

[0085] The feedstock oil first enters the first adsorption refiner 1 for adsorption purification. The adsorption purification conditions are as follows: the amount of bleaching clay added to the first adsorption refiner 1 is 10% of the feedstock oil mass, the reaction temperature is 90℃, and the reaction time is 90 min. The purified feedstock oil enters through the light phase inlet of the multi-stage centrifugal extractor 2, and the extraction solvent enters through the heavy phase inlet. The volume ratio of solvent A (furfural) to solvent B (N-methylpyrrolidone) in the extraction solvent is 1:1. The solvent extraction operating conditions are as follows: the solvent to feedstock oil mass ratio is 4:1, the light phase inlet temperature is 100℃, the heavy phase inlet temperature of the multi-stage centrifugal extractor is 120℃, the extraction pressure is 0.1 MPa, the number of extraction stages is 5, the residence time is 120 min, and the separation factor is 1000; the extracted oil and the raffinate oil are separated.

[0086] The extracted oil enters the heavy phase settling tank 3, and the residual oil enters the light phase settling tank 7. The settling time is 120 minutes, and the temperature is 40℃. The upper layer extracted oil, lower layer extracted oil, upper layer residual oil, and lower layer residual oil are separated. The lower layer extracted oil and the upper layer residual oil are separately subjected to solvent separation. The upper layer extracted oil and the lower layer residual oil are mixed and then subjected to solvent separation. The separated upper layer extracted oil and lower layer residual oil are combined to form a low-aromatic environmentally friendly rubber oil.

[0087] The separated lower-extracted oil is refined in a second adsorption refiner 4. The adsorption refining conditions are: activated carbon dosage is 5% of the lower-extracted oil mass, adsorption time is 40 min, and adsorption temperature is 80℃. This yields C. A This is an environmentally friendly high-aromatic rubber oil with a content of 32.0%. See Table 1 for detailed parameters.

[0088] Example 21:

[0089] like Figure 1 As shown, the raw material oil in this embodiment is the same as that in embodiment 20.

[0090] The feedstock oil first enters the first adsorption refiner 1 for adsorption purification. The adsorption purification conditions are as follows: the amount of clay added to the first adsorption refiner 1 is 12% of the feedstock oil mass, the reaction temperature is 120℃, and the reaction time is 110 min. The purified feedstock oil enters through the light phase inlet of the multi-stage centrifugal extractor 2, and the extraction solvent enters through the heavy phase inlet. The volume ratio of solvent A (dimethyl sulfoxide) to solvent B (N,N-dimethylformamide) in the extraction solvent is 4:6. The solvent extraction operating conditions are as follows: the solvent to feedstock oil mass ratio is 8:1, the light phase inlet temperature is 80℃, the heavy phase inlet temperature of the multi-stage centrifugal extractor is 100℃, the extraction pressure is 0.1 MPa, the number of extraction stages is 4, the residence time is 30 min, and the separation factor is 1200; the extracted oil and the raffinate oil are separated.

[0091] The extracted oil enters the heavy phase settling tank 3, and the residual oil enters the light phase settling tank 7. The settling time is 100 minutes, and the temperature is 50℃. The upper layer extracted oil, lower layer extracted oil, upper layer residual oil, and lower layer residual oil are separated. The lower layer extracted oil and the upper layer residual oil are separately subjected to solvent separation. The upper layer extracted oil and the lower layer residual oil are mixed and then subjected to solvent separation. The separated upper layer extracted oil and lower layer residual oil are combined to form a low-aromatic environmentally friendly rubber oil.

[0092] The separated lower-extracted oil is refined in a second adsorption refiner 4. The adsorption refining conditions are: activated carbon dosage is 15% of the lower-extracted oil mass, adsorption time is 60 min, and adsorption temperature is 80℃. This yields C. A This is an environmentally friendly high-aromatic rubber oil with a content of 29.9%. See Table 1 for detailed parameters.

[0093] Example 22:

[0094] like Figure 1 As shown, the feedstock oil in this embodiment is a naphthenic reduced-four fraction oil with a molecular weight of 520, an aromatic content of 23.3%, and a distillation range of 390°C to 550°C.

[0095] The feedstock oil first enters the first adsorption refiner 1 for adsorption purification. The adsorption purification conditions are as follows: the amount of bleaching clay added to the first adsorption refiner 1 is 15% of the feedstock oil mass, the reaction temperature is 110℃, and the reaction time is 100 min. The purified feedstock oil enters through the light phase inlet of the multi-stage centrifugal extractor 2, while the extraction solvent enters through the heavy phase inlet. The volume ratio of solvent A (sulfolane:furfural = 3:3) to solvent B (diacetone alcohol) in the extraction solvent is 6:4. The solvent extraction operating conditions are as follows: the mass ratio of solvent to feedstock oil is 5:1, the light phase inlet temperature is 120℃, the heavy phase inlet temperature of the multi-stage centrifugal extractor is 140℃, the extraction pressure is 0.03 MPa, the number of extraction stages is 6, the residence time is 120 min, and the separation factor is 800; the extracted oil and the raffinate oil are separated.

[0096] The extracted oil enters the heavy phase settling tank 3, and the residual oil enters the light phase settling tank 7. The settling time is 80 minutes, and the temperature is 40℃. The upper layer extracted oil, lower layer extracted oil, upper layer residual oil, and lower layer residual oil are separated. The lower layer extracted oil and the upper layer residual oil are separately subjected to solvent separation. The upper layer extracted oil and the lower layer residual oil are mixed and then subjected to solvent separation. The separated upper layer extracted oil and lower layer residual oil are combined to form a low-aromatic environmentally friendly rubber oil.

[0097] The separated lower-extracted oil is refined in a second adsorption refiner 4. The adsorption refining conditions are: activated carbon dosage is 15% of the lower-extracted oil mass, adsorption time is 50 min, and adsorption temperature is 80℃. This yields C. A This is an environmentally friendly high-aromatic rubber oil with a content of 29.3%. See Table 1 for detailed parameters.

[0098] Example 23:

[0099] like Figure 1 As shown, the raw material oil in this embodiment is the same as that in embodiment 22.

[0100] The feedstock oil first enters the first adsorption refiner 1 for adsorption purification. The adsorption purification conditions are as follows: the amount of bleaching clay added to the first adsorption refiner 1 is 20% of the feedstock oil mass, the reaction temperature is 120℃, and the reaction time is 120 min. The purified feedstock oil enters through the light phase inlet of the multi-stage centrifugal extractor 2, and the extraction solvent enters through the heavy phase inlet. The volume ratio of solvent A (furfural) to solvent B (diacetone alcohol) in the extraction solvent is 3:7. The solvent extraction operating conditions are as follows: the mass ratio of solvent to feedstock oil is 10:1, the light phase inlet temperature is 80℃, the heavy phase inlet temperature of the multi-stage centrifugal extractor is 110℃, the extraction pressure is 0.08 MPa, the number of extraction stages is 5, the residence time is 40 min, and the separation factor is 1200; the extracted oil and the raffinate oil are separated.

[0101] The extracted oil enters the heavy phase settling tank 3, and the residual oil enters the light phase settling tank 7. The settling time is 60 minutes, and the temperature is 60℃. The upper layer extracted oil, lower layer extracted oil, upper layer residual oil, and lower layer residual oil are separated. The lower layer extracted oil and the upper layer residual oil are separately subjected to solvent separation. The upper layer extracted oil and the lower layer residual oil are mixed and then subjected to solvent separation. The separated upper layer extracted oil and lower layer residual oil are combined to form a low-aromatic environmentally friendly rubber oil.

[0102] The separated lower-extracted oil is refined in a second adsorption refiner 4. The adsorption refining conditions are: activated carbon dosage is 20% of the lower-extracted oil mass, adsorption time is 60 min, and adsorption temperature is 100℃. This yields C. A This is an environmentally friendly high-aromatic rubber oil with a content of 30.9%. See Table 1 for detailed parameters.

[0103] Comparative Example 1:

[0104] like Figure 1 As shown, the feedstock oil in this embodiment is the same as in Example 16. Solvent extraction (using a solvent extraction tower as the implementation device) is employed for separation. The feedstock enters from the upper inlet of the solvent extraction tower, and the extraction solvent, furfural, enters from the lower inlet. The solvent extraction operating conditions are as follows: solvent to feedstock oil mass ratio of 0.5:1, upper inlet temperature 30°C, and lower inlet temperature 60°C. The extracted oil and raffinate oil are separately subjected to solvent separation. The separated raffinate oil is used as feedstock for catalytic cracking, and the extracted oil undergoes adsorption refining treatment (adsorption refining conditions: activated carbon dosage 20% of the extracted oil mass, adsorption time 60 min, adsorption temperature 80°C) to obtain C. A Aromatic rubber oil with a content of 13.5%. Detailed parameters are shown in Table 1.

[0105] Comparative Example 2:

[0106] like ​ As shown, the feedstock oil in this embodiment is the same as in Example 22. Solvent extraction (using a solvent extraction tower as the implementation device) is employed for separation. The feedstock oil enters from the upper inlet of the solvent extraction tower, and the extraction solvent, dimethyl sulfoxide, enters from the lower inlet. The solvent extraction operating conditions are as follows: solvent to feedstock oil mass ratio of 10:1, upper inlet temperature 80℃, and lower inlet temperature 110℃. Upper extract oil, lower extract oil, upper raffinate oil, and lower raffinate oil are separated. The lower extract oil and upper raffinate oil are separately solvent-separated; the upper extract oil and lower raffinate oil are mixed and then solvent-separated. The separated upper extract oil and lower raffinate oil are combined to form a low-aromatic environmentally friendly rubber oil. The separated lower extract oil undergoes adsorption refining treatment (adsorption refining conditions: activated carbon dosage 20% of the lower extract oil mass, adsorption time 60 min, adsorption temperature 80℃) to obtain an aromatic rubber oil with a CA value of 15.7%. Detailed parameters are shown in Table 1.

[0107] In summary, this invention provides a method and apparatus for enriching aromatics. This method can simultaneously achieve both oil yield and aromatic selectivity, obtaining aromatic-rich components with an aromatic content greater than 75% and an aromatic extraction rate greater than 60%, and ultimately obtaining C... A It is a high-aromatic environmentally friendly rubber oil with 20% to 30% aromatics, which further improves the utilization rate of mono- and bi-cyclic aromatics in vacuum distillate oil, can achieve continuous operation, and has high refining efficiency and high recovery rate.

[0108] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effect. Unnecessary technical features can be added or removed according to actual needs to meet the needs of different situations.

[0109]

Claims

1. A process for enriching aromatic hydrocarbon components, characterized by The following steps are taken: In the first step, the raw oil is subjected to primary adsorption refining and then enters a multi-stage centrifugal extractor. In the multi-stage centrifugal extractor, the extraction solvent and the raw oil are in countercurrent contact for solvent extraction, obtaining raffinate oil and extracted oil. In the second step, the extracted oil is subjected to settling separation, obtaining upper extracted oil and lower extracted oil. In the third step, the lower extracted oil is sequentially subjected to solvent separation and secondary adsorption refining, completing the enrichment and separation of high-aromatic oil in the raw oil to obtain high-aromatic environmentally friendly rubber oil. In the fourth step, the raffinate oil obtained in the first step is subjected to settling separation, obtaining upper raffinate oil and lower raffinate oil. In the fifth step, the lower raffinate oil and the upper extracted oil obtained in the second step are combined and subjected to solvent separation, completing the enrichment and separation of low-aromatic oil in the raw oil to obtain low-aromatic environmentally friendly rubber oil. The upper raffinate oil is subjected to solvent separation to obtain catalytic cracking material and lubricating oil base oil. In the first step, the raw oil is naphthenic vacuum distillate oil or light deoiled oil, with a distillation range of 300-550℃ and a molecular weight of 320-520. The aromatic content in the raw oil is 20.0%-27.5%, and the paraffin content is not higher than 50%. The operating conditions for solvent extraction in the multi-stage centrifugal extractor are as follows: the mass ratio of extraction solvent to raw oil is 0.5:1-10:1, the temperature of the light phase inlet of the multi-stage centrifugal extractor is 30-120℃, the temperature of the heavy phase inlet of the multi-stage centrifugal extractor is 60-140℃, and the extraction pressure is 0.01-0.1MPa. The extraction solvent is A-B mixed solvent, wherein solvent A is a strong polar solvent, accounting for 30%-60% of the total volume of the extraction solvent, and solvent B is a weak polar solvent, accounting for 40%-70% of the total volume of the extraction solvent. The operating conditions for the primary adsorption refining are as follows: the adsorbent is clay, the adsorbent dosage is 5%-20% of the mass of the raw oil, the reaction temperature is 60-120℃, and the reaction time is 30-120min. The operating conditions for the secondary adsorption refining are as follows: the adsorbent is powdered activated carbon with oxygen-containing functional groups, the adsorbent dosage is 0.2%-20% of the mass of the lower extracted oil, the adsorption time is 30-60min, and the adsorption temperature is 40-100℃.

2. The method of enriching aromatic hydrocarbon components according to claim 1, characterized by In the first step, the operating conditions for solvent extraction in the multi-stage centrifugal extractor are as follows: the mass ratio of extraction solvent to raw oil is 2:1-6:1, the temperature of the light phase inlet of the multi-stage centrifugal extractor is 40-100℃, the temperature of the heavy phase inlet of the multi-stage centrifugal extractor is 70-110℃, and the extraction pressure is 0.01-0.05MPa.

3. The method of enriching aromatic hydrocarbon components according to claim 1 or 2, characterized in that In the first step, the number of centrifugal extractors in the multi-stage centrifugal extractor is i, and 2≤i≤6; or / and, the residence time of the raw oil and the extraction solvent in the multi-stage centrifugal extractor is 30s-120min, and the separation factor of the multi-stage centrifugal extractor is 500-1500.

4. The method of enriching aromatic hydrocarbon components according to claim 1, characterized by Solvent A is one or more of sulfolane, dimethyl sulfoxide, and furfural; and solvent B is diacetone alcohol.

5. The method of enriching aromatic hydrocarbon components according to claim 1 or 2, characterized by In the second and fourth steps, the operating conditions for settling separation are as follows: the settling time is 30-120min, and the settling temperature is 30-80℃.

6. An apparatus for carrying out the process for enriching aromatic hydrocarbon components according to any one of claims 1 to 5, characterized in that The application relates to a crude oil refining system, which comprises a first adsorption refiner, a multi-stage centrifugal extractor, a heavy phase settling tank, a second adsorption refiner, a heavy phase desolventizer, a mixed desolventizer, a raw oil feeding pipeline is fixedly connected to the feeding end of the first adsorption refiner, a centrifugal extraction pipeline is fixedly connected between the discharging end of the first adsorption refiner and the primary light phase feeding port of the multi-stage centrifugal extractor, an extraction solvent feeding pipeline is fixedly connected to the final heavy phase feeding port of the multi-stage centrifugal extractor, an extracted oil pipeline is fixedly connected between the primary discharging port of the multi-stage centrifugal extractor and the heavy phase settling tank, an upper extracted oil pipeline is fixedly connected between the first discharging end of the heavy phase settling tank and the feeding end of the mixed desolventizer, a low-aromatic oil pipeline is fixedly connected to the discharging end of the mixed desolventizer, a heavy phase desolventizing pipeline is fixedly connected between the second discharging end of the heavy phase settling tank and the feeding end of the heavy phase desolventizer, a secondary adsorption refining pipeline is fixedly connected between the discharging end of the heavy phase desolventizer and the second adsorption refiner, and a high-aromatic oil pipeline is fixedly connected to the discharging end of the second adsorption refiner; the system further comprises a light phase settling tank and a light phase desolventizer, an extracted oil total pipeline is fixedly connected between the final discharging port of the multi-stage centrifugal extractor and the feeding end of the light phase settling tank, an upper extracted oil pipeline is fixedly connected between the first discharging end of the light phase settling tank and the feeding end of the light phase desolventizer, a non-aromatic oil pipeline is fixedly connected to the discharging end of the light phase desolventizer, and a lower extracted oil pipeline is fixedly connected between the second discharging end of the light phase settling tank and the upper extracted oil pipeline; or / and, a mixed desolventizing pipeline is fixedly connected between the extracted oil total pipeline and the upper extracted oil pipeline between the heavy phase settling tank and the lower extracted oil pipeline.

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