Method for treating hydrocarbon oil

Abstract

The invention relates to a method for treating hydrocarbon oil. The method comprises the following steps: fractionating a gasoline raw material to obtain a benzene-poor light fraction, a benzene-poor heavy fraction and a benzene-rich middle fraction; then contacting the benzene-poor light fraction and / or the benzene-poor heavy fraction and a first hydrogen donor with a first catalyst in a desulfurization reactor, and carrying out desulfurization reaction under a selective desulfurization condition, and contacting the benzene-rich middle fraction and a second hydrogen donor with a second catalyst in a debenzolization reactor and carrying out a hydrogenation reaction under hydrogenation reaction conditions to convert benzene into cyclohexane. According to the present invention, the benzene-poor fraction is subjected to high-selectivity deep desulfurization, the octane number loss is less, the hydrogenation saturation of benzene in the benzene-rich fraction is achieved so as to reduce the benzene content in the refined product, and the hydrofined hydrocarbon oil can be adopted as the blending component to produce the clean gasoline with characteristics of low benzene content and low sulfur content.

Description

Technical Field

[0001] The invention belongs to the field of petrochemical industry, and in particular, relates to a method for processing hydrocarbon oil. Background Art

[0002] In recent years, environmental regulations have increasingly tightened restrictions on automobile exhaust emissions, and countries around the world have increasingly higher requirements for the benzene content in gasoline, and the demand for clean oil products with lower benzene content has become more and more obvious. The current National VI gasoline quality standard GB 17930-2016 stipulates that the volume fraction of benzene in gasoline should not exceed 0.8%, and that the sulfur content in gasoline should be below 10 micrograms / gram. Because benzene has a strong carcinogenic effect, future quality regulations may further reduce the benzene content in gasoline.

[0003] The main sources of the catalytic gasoline pool include catalytic cracking gasoline, reformed gasoline, alkylate, etc. In China, the proportion of catalytic cracking gasoline in the gasoline pool is as high as about 70%, so reducing the benzene and sulfur content in catalytic cracking gasoline can become the basis for ensuring that the benzene and sulfur content of the gasoline pool is qualified. Moreover, as a high-octane component of the gasoline pool, the benzene content of reformed gasoline must also be strictly controlled before blending.

[0004] CN101451076A discloses a method for reducing the benzene content in gasoline. The method conducts an alkylation translocation reaction between gasoline or a benzene-rich fraction in gasoline and a polyalkylbenzene raw material under the action of a solid acid catalyst, which can significantly reduce the benzene content in gasoline without any loss of octane number or gasoline yield, and does not require subsequent separation.

[0005] CN103725312A discloses a catalytic conversion method for reducing the benzene content in a benzene-rich gasoline component. The method can reduce the problems caused by excessively high reaction temperature, excessively low pressure, and too low mass ratio of secondary benzene gasoline component to methanol during the alkylation reaction between the benzene-rich gasoline component and methanol.

[0006] The benzene content in hydrocarbon oil can be reduced by using an alkylation process or by using a hydrogenation method to hydrogenate and saturate the benzene-rich fraction. For example, the Bensat process developed by UOP can process the benzene-rich fraction of reforming oil. The benzene in the benzene-rich fraction is highly selectively hydrogenated and saturated to cyclohexane on a highly selective fixed-bed catalyst. This process only requires slightly more hydrogen than the stoichiometric amount, but requires the use of the precious metal Pt as a catalyst, which is relatively expensive.

[0007] However, the benzene content and sulfur content in the hydrocarbon oil obtained by the existing hydrocarbon oil conversion methods still need to be further reduced. Summary of the invention

[0008] The object of the present invention is to provide a method for treating hydrocarbon oil, by which the benzene content and the sulfur content in the hydrocarbon oil can be reduced simultaneously and the conversion efficiency of benzene can be improved.

[0009] In order to achieve the above object, the first aspect of the present invention provides a method for treating hydrocarbon oil, comprising the following steps:

[0010] (1) fractionating a hydrocarbon oil feedstock to obtain a benzene-poor light fraction, a benzene-poor heavy fraction, and a benzene-rich middle fraction; the initial distillation point of the benzene-rich middle fraction is any temperature between 55 and 70° C., and the final distillation point is any temperature between 90 and 130° C.;

[0011] (2) contacting the benzene-depleted light fraction and / or the benzene-depleted heavy fraction and a first hydrogen donor with a first catalyst in a desulfurization reactor and performing a desulfurization reaction under selective desulfurization conditions to obtain a first hydrocarbon oil and a first spent catalyst;

[0012] (3) contacting the benzene-rich middle fraction and the second hydrogen donor with a second catalyst in a debenzenization reactor and performing a hydrogenation reaction under hydrogenation reaction conditions to convert benzene into cyclohexane to obtain a second hydrocarbon oil and a second spent catalyst;

[0013] (4) The first catalyst to be regenerated and the second catalyst to be regenerated are subjected to oxygen-containing charring, stripping and reduction in sequence to obtain a first regenerated catalyst and a second regenerated catalyst, and the first regenerated catalyst is returned to the desulfurization reactor for a selective desulfurization reaction, and the second regenerated catalyst is returned to the debenzenization reactor for a hydrogenation reaction.

[0014] Optionally, the hydrocarbon oil feedstock is selected from one or more of catalytic cracking gasoline, catalytic pyrolysis gasoline and reforming gasoline; the sulfur content of the hydrocarbon oil feedstock is 10 to 5000 μg / g, and the mass percentage of benzene in the hydrocarbon oil feedstock is 0.7 to 10%; preferably, the sulfur content of the hydrocarbon oil feedstock is 30 to 3000 μg / g, and the mass percentage of benzene in the hydrocarbon oil feedstock is 0.8 to 5%.

[0015] Optionally, the distillation pressure during the distillation is 0.1 to 1.0 MPa, preferably 0.1 to 0.5 MPa.

[0016] Optionally, the first catalyst and the second catalyst each include a carrier and a metal active component; based on the weight of the carrier, the carrier includes 20 to 85 wt% of zinc oxide, 10 to 75 wt% of aluminum oxide and 5 to 70 wt% of silica; based on the weight of the first catalyst and the second catalyst, the content of the metal active component in the first catalyst and the second catalyst is each 5 to 30 wt%; the active metal component is selected from one or more of cobalt, nickel, iron, manganese, copper, molybdenum, tungsten, silver, tin and vanadium.

[0017] Optionally, the first hydrogen donor and the second hydrogen donor are each independently selected from one or more of hydrogen, a mixed gas containing hydrogen and a hydrogen donor; the hydrogen donor is selected from one or more of tetralin, decalin and dihydroindene; preferably, the volume fraction of hydrogen in the first hydrogen donor and the second hydrogen donor is each independently 50-100%.

[0018] Optionally, the average particle size of the first catalyst and the second catalyst is independently 20-200 μm, and the wear index is 2.0-8.0%; preferably, the average particle size of the first catalyst and the second catalyst is independently 40-100 μm, and the wear index is 3.0-6.0%.

[0019] Optionally, the conditions of the desulfurization reaction include: a reaction temperature of 300 to 480°C, a reaction pressure of 0.1 to 5.0 MPa, a volume ratio of the first hydrogen donor to the benzene-depleted light fraction and / or the benzene-depleted heavy fraction of (10 to 200): 1, and a weight hourly space velocity of the benzene-depleted light fraction and / or the benzene-depleted heavy fraction of 0.5 to 20 h -1 Preferably, in the desulfurization reactor, the reaction temperature is 350-450°C, the reaction pressure is 0.5-3.5 MPa, the volume ratio of the first hydrogen donor to the benzene-depleted light fraction and / or the benzene-depleted heavy fraction is (20-100):1, and the weight hourly space velocity of the benzene-depleted light fraction and / or the benzene-depleted heavy fraction is 1.5-10 h -1 .

[0020] Optionally, the conditions of the hydrogenation reaction include: a reaction temperature of 150 to 450° C., a reaction pressure of 0.5 to 8.0 MPa, a volume ratio of the second hydrogen donor to the benzene-rich middle distillate of (100 to 2000):1, and a weight hourly space velocity of the benzene-rich middle distillate of 0.2 to 10 h -1 Preferably, the reaction temperature of the hydrogenation reaction is 250-400°C, the reaction pressure is 1.5-3.5 MPa, the volume ratio of the second hydrogen donor to the benzene-rich middle distillate is (300-1000):1, and the weight hourly space velocity of the benzene-rich middle distillate is 1.5-5h-1 .

[0021] Optionally, the method further includes: preheating the benzene-depleted light fraction and / or the benzene-depleted heavy fraction and the first hydrogen donor to 300-500°C before carrying out the desulfurization reaction; and preheating the benzene-rich intermediate fraction and the second hydrogen donor to 150-400°C before carrying out the hydrogenation reaction.

[0022] Optionally, the oxygen-containing coking is carried out in the presence of an oxygen-containing gas, and the conditions for the oxygen-containing coking include: a temperature of 300-800°C and a pressure of 0.1-3.0 MPa; preferably, a temperature of 350-600°C and a pressure of 0.1-1.0 MPa; wherein the oxygen-containing gas is selected from one of air, a mixed gas of oxygen and nitrogen, and a mixed gas of air and nitrogen; the volume fraction of oxygen in the oxygen-containing gas is 5-50%; and the medium used for the stripping is selected from nitrogen and / or CO2.

[0023] Optionally, the reduction of the first catalyst to be generated and the second catalyst to be generated is performed in a reducing gas atmosphere; the reducing gas is hydrogen or a mixed gas containing hydrogen; the volume fraction of hydrogen in the mixed gas containing hydrogen is 50-100%.

[0024] Optionally, the reduction conditions include: a reduction temperature of 300 to 480° C. and a reduction pressure of 0.1 to 10 MPa; preferably, the reduction temperature is 350 to 450° C. and the reduction pressure is 0.5 to 5 MPa.

[0025] Optionally, the method further comprises: mixing the first hydrocarbon oil and the second hydrocarbon oil to obtain refined hydrocarbon oil.

[0026] Through the above technical scheme, the present invention achieves hydrogenation saturation of benzene in the benzene-rich fraction while achieving high-selectivity deep desulfurization of the benzene-poor fraction and low octane number loss, thereby reducing the benzene content in the refined product. The hydrocarbon oil after hydrorefining can be used as a blending component to produce clean gasoline with low benzene and sulfur contents.

[0027] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0029] Figure 1 It is a schematic flow chart of an embodiment of the method for treating hydrocarbon oil provided by the present invention.

[0030] Figure 2 It is a schematic flow chart of another embodiment of the method for treating hydrocarbon oil provided by the present invention.

[0031] Description of Reference Numerals

[0032] 1 pipeline 2 fractionation tower 3 pipeline

[0033] 4 pipelines 5 pipelines 6 pipelines

[0034] 7 Debenzene Reactor 8 Pipeline 9 Pipeline

[0035] 10 first receiver 11 pipeline 12 lock hopper

[0036] 13 pipeline 14 pipeline 15 regenerator feeder

[0037] 16 pipeline 17 pipeline 18 regenerator

[0038] 19 pipeline 20 pipeline 21 regenerator receiver

[0039] 22 pipeline 23 pipeline 24 second reducer

[0040] 25 pipeline 26 pipeline 27 desulfurization reactor

[0041] 28 pipeline 29 pipeline 30 second receiver

[0042] 31 pipeline 32 pipeline 33 first reducer

[0043] 34 pipeline DETAILED DESCRIPTION

[0044] The specific embodiments of the present invention are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0045] A first aspect of the present invention provides a method for treating hydrocarbon oil, comprising the following steps:

[0046] (1) fractionating a hydrocarbon oil feedstock to obtain a benzene-poor light fraction, a benzene-poor heavy fraction, and a benzene-rich middle fraction; the initial distillation point of the benzene-rich middle fraction is any temperature between 55 and 70° C., and the final distillation point is any temperature between 90 and 130° C.;

[0047] (2) contacting the benzene-depleted light fraction and / or the benzene-depleted heavy fraction and a first hydrogen donor with a first catalyst in a desulfurization reactor and performing a desulfurization reaction under selective desulfurization conditions to obtain a first hydrocarbon oil and a first spent catalyst;

[0048] (3) contacting the benzene-rich middle fraction and the second hydrogen donor with a second catalyst in a debenzenization reactor and performing a hydrogenation reaction under hydrogenation reaction conditions to convert benzene into cyclohexane to obtain a second hydrocarbon oil and a second spent catalyst;

[0049] (4) The first catalyst to be regenerated and the second catalyst to be regenerated are subjected to oxygen-containing charring, stripping and reduction in sequence to obtain a first regenerated catalyst and a second regenerated catalyst, and the first regenerated catalyst is returned to the desulfurization reactor for a selective desulfurization reaction, and the second regenerated catalyst is returned to the debenzenization reactor for a hydrogenation reaction.

[0050] Through the above technical scheme, the present invention performs a hydrogenation saturation reaction on the benzene-rich middle fraction obtained by fractionation of the whole fraction gasoline to remove benzene and sulfur therein, and performs a desulfurization reaction on the benzene-poor light fraction and the benzene-poor heavy fraction to remove sulfur therein, while the benzene-poor fraction is highly selectively deeply desulfurized and the octane number loss is small, and the hydrogenation saturation of benzene in the benzene-rich fraction is achieved, thereby reducing the benzene content in the refined product, and the hydrocarbon oil after hydrorefining can be used as a blending component to produce clean gasoline with low benzene content and sulfur content. Moreover, by coupling the selective adsorption desulfurization and the deep hydrogenation of benzene, the cost of equipment investment and operation is reduced.

[0051] The catalyst after the desulfurization reaction can be regenerated by contacting with oxygen-containing gas and reduced and then returned to the desulfurization reactor for continued use. The catalyst deactivated after the hydrodebenzening reaction can be regenerated by contacting with oxygen-containing gas and reduced with hydrogen and then continued to be used in the desulfurization reaction and debenzening reaction.

[0052] The hydrocarbon oil feedstock is selected from one or more of catalytic cracking gasoline, catalytic pyrolysis gasoline and reforming gasoline; the sulfur content of the hydrocarbon oil feedstock is 10 to 5000 μg / g, and the mass percentage of benzene in the hydrocarbon oil feedstock is 0.7 to 10%; preferably, the sulfur content of the hydrocarbon oil feedstock is 30 to 3000 μg / g, and the mass percentage of benzene in the hydrocarbon oil feedstock is 0.8 to 5%.

[0053] The mass fraction of olefins in the hydrocarbon oil feedstock is 2-50%, preferably 5-40%, and the mass fraction of aromatics is above 20%, preferably above 30%.

[0054] The final boiling point of the hydrocarbon oil feedstock in the present invention is 220°C or lower, preferably 200°C or lower.

[0055] Wherein, the fractionation pressure during the fractionation is 0.1-1.0 MPa, preferably 0.1-0.5 MPa.

[0056] In the present invention, the full-component gasoline raw material is fractionated in a fractionating tower to obtain a benzene-rich fraction (middle fraction) and a benzene-poor fraction (light fraction or heavy fraction or a mixture of light and heavy fractions), the initial distillation point of the benzene-rich fraction is 55-70°C, and the final distillation point is 90-130°C.

[0057] Wherein, the first catalyst and the second catalyst each include a carrier and a metal active component; based on the weight of the carrier, the carrier includes 20-85wt% of zinc oxide, 10-75wt% of aluminum oxide and 5-70wt% of silica; based on the weight of the first catalyst and the second catalyst each, the content of the metal active component in the first catalyst and the second catalyst is each 5-30wt%; the active metal component is selected from one or more of cobalt, nickel, iron, manganese, copper, molybdenum, tungsten, silver, tin and vanadium.

[0058] In the present invention, the carrier is prepared by pulping, mixing, molding, drying and calcining; the active metal component is loaded onto the carrier by impregnation, spraying and the like, and then dried and calcined to obtain a catalyst.

[0059] In the present invention, in order to facilitate the fluidization of the first catalyst and the second catalyst, the first catalyst and the second catalyst are preferably in the form of microspheres, and the average particle diameters thereof are independently 20 to 200 μm, preferably 40 to 100 μm.

[0060] Wherein, the first hydrogen donor and the second hydrogen donor are independently selected from one or more of hydrogen, a mixed gas containing hydrogen and a hydrogen donor; the hydrogen donor is selected from one or more of tetralin, decalin and dihydroindene; preferably, the volume fraction of hydrogen in the first hydrogen donor and the second hydrogen donor is independently 50-100%.

[0061] The average particle size of the first catalyst and the second catalyst is independently 20-200 μm, and the wear index is 2.0-8.0%; preferably, the average particle size of the first catalyst and the second catalyst is independently 40-100 μm, and the wear index is 3.0-6.0%.

[0062] The conditions of the desulfurization reaction include: a reaction temperature of 300 to 480°C, a reaction pressure of 0.1 to 5.0 MPa, a volume ratio of the first hydrogen donor to the benzene-poor light fraction and / or the benzene-poor heavy fraction of (10 to 200): 1, and a weight hourly space velocity of the benzene-poor light fraction and / or the benzene-poor heavy fraction of 0.5 to 20 h -1Preferably, in the desulfurization reactor, the reaction temperature is 350-450°C, the reaction pressure is 0.5-3.5 MPa, the volume ratio of the first hydrogen donor to the benzene-depleted light fraction and / or the benzene-depleted heavy fraction is (20-100):1, and the weight hourly space velocity of the benzene-depleted light fraction and / or the benzene-depleted heavy fraction is 1.5-10 h -1 The above-mentioned desulfurization reaction conditions can not only achieve deep desulfurization of the benzene-poor fraction, but also reduce the octane number loss of the benzene-poor fraction.

[0063] In the present invention, the desulfurization reactor and the debenzenization reactor are each preferably a fluidized bed reactor, and the top of the fluidized bed reactor is provided with a settling section, a separation section and a filter for further separating the reaction oil gas and the catalyst.

[0064] The conditions of the hydrogenation reaction include: a reaction temperature of 150 to 450° C., a reaction pressure of 0.5 to 8.0 MPa, a volume ratio of the second hydrogen donor to the benzene-rich middle distillate of (100 to 2000):1, and a weight hourly space velocity of the benzene-rich middle distillate of 0.2 to 10 h -1 Preferably, the reaction temperature of the hydrogenation reaction is 250-400°C, the reaction pressure is 1.5-3.5 MPa, the volume ratio of the second hydrogen donor to the benzene-rich middle distillate is (300-1000):1, and the weight hourly space velocity of the benzene-rich middle distillate is 1.5-5h -1 Under the above-mentioned hydrogenation saturation reaction conditions, sulfur and benzene in the benzene-rich fraction can be removed, while avoiding excessive loss of gasoline octane number, and the consumption of the second hydrogen donor is also controlled within a reasonable range, with good economic efficiency.

[0065] The method further includes: preheating the benzene-poor light fraction and / or the benzene-poor heavy fraction and the first hydrogen donor to 300-500°C before the desulfurization reaction; and preheating the benzene-rich middle fraction and the second hydrogen donor to 150-400°C before the hydrogenation reaction.

[0066] The oxygen-containing coking is carried out in the presence of an oxygen-containing gas, and the conditions for the oxygen-containing coking include: a temperature of 300-800°C and a pressure of 0.1-3.0 MPa; preferably, a temperature of 350-600°C and a pressure of 0.1-1.0 MPa; the oxygen-containing gas is selected from one of air, a mixed gas of oxygen and nitrogen, and a mixed gas of air and nitrogen; the volume fraction of oxygen in the oxygen-containing gas is 5-50%; the medium used for the stripping is selected from nitrogen and / or CO2.

[0067] The reduction of the first catalyst to be regenerated and the second catalyst to be regenerated is performed in a reducing gas atmosphere; the reducing gas is hydrogen or a mixed gas containing hydrogen; the volume fraction of hydrogen in the mixed gas containing hydrogen is 50-100%.

[0068] The reduction conditions include: a reduction temperature of 300 to 480° C. and a reduction pressure of 0.1 to 10 MPa; preferably, the reduction temperature is 350 to 450° C. and the reduction pressure is 0.5 to 5 MPa.

[0069] In the present invention, in order to suppress the temperature rise of the debenzenization reactor, the hydrogenated saturated reaction product can be returned to mix with the benzene-rich middle distillate, and the mass ratio of the returned hydrogenated refined product to the benzene-rich middle distillate is 0.2-5, preferably 0.5-3.

[0070] Wherein, the method further comprises: mixing the first hydrocarbon oil and the second hydrocarbon oil to obtain refined hydrocarbon oil.

[0071] In a specific embodiment of the present invention, Figure 1 As shown, the hydrocarbon oil feedstock containing benzene enters the middle part of the fractionation tower through pipeline 1, and is fractionated to obtain a benzene-poor light fraction, a benzene-rich middle fraction, and a benzene-poor heavy fraction. The benzene-rich middle fraction is preheated and mixed with the second hydrogen donor from pipeline 6 through pipeline 4, enters from the bottom of the debenzenization reactor 7, passes through the debenzenization reactor 7 from bottom to top, and contacts with the second catalyst in the debenzenization reactor 7 for hydrogenation reaction to convert benzene into cyclohexane. The hydrocarbon oil material after hydrogenation reaction and the second catalyst to be regenerated enter the sedimentation separation section and filter at the top of the debenzenization reactor 7 for oil separation, and the hydrocarbon oil after debenzenization is sent to the subsequent product separation and stabilization system through pipeline 8 for further processing.

[0072] The second catalyst to be regenerated after the hydrogenation reaction is sent to the first receiver 10 through pipeline 9 for stripping to remove the oil and gas adsorbed on the second catalyst to be regenerated. The second catalyst to be regenerated after the hydrocarbon oil is removed is sent to the lock hopper 12 through pipeline 11. After nitrogen replacement in the lock hopper 12, the high-pressure hydrogen environment is changed to a low-pressure nitrogen environment. The replaced gas is sent to the combustion furnace for treatment through pipeline 13. The second catalyst to be regenerated is sent to the regenerator feeder 15 through pipeline 14. The second catalyst to be regenerated is lifted by the lifting gas through pipeline 16 and sent to the regenerator 18 to contact with the oxygen-containing gas. The oxygen-containing gas is passed into the regenerator 18 from the bottom of the regenerator 18 through pipeline 17 for regeneration to remove the sulfur and carbon loaded on the second catalyst to be regenerated. The sulfur-containing regenerated flue gas is separated at the top of the regenerator 18 and then transported to the sulfur production unit or flue gas treatment unit through pipeline 19. The second regenerated catalyst is transported to the regenerator receiver 21 via pipeline 20 for stripping, and is passed through an inactive gas medium such as nitrogen and CO2 to reduce the oxygen carried by the second regenerated catalyst. Then, it enters the lock hopper 12 via pipeline 22, and is converted from a low-pressure oxygen-containing environment to a high-pressure hydrogen-containing environment. The second regenerated catalyst after gas replacement is transported to the debenzenization reactor reducer 24 via pipeline 23 for reduction. The reduced second regenerated catalyst is returned to the debenzenization reactor 7 via pipeline 25 to continue to participate in the debenzenization reaction of the benzene-rich intermediate fraction.

[0073] The preheated benzene-depleted light fraction and the benzene-depleted heavy fraction are mixed with the first hydrogen donor from pipeline 26 via pipeline 3 and pipeline 5 respectively, enter the desulfurization reactor 27 from the bottom of the desulfurization reactor 27, contact with the first catalyst in the desulfurization reactor 27 for selective desulfurization reaction, and the hydrocarbon oil material after the desulfurization reaction and the first catalyst to be generated enter the sedimentation separation section and filter at the top of the desulfurization reactor 27 for oil-agent separation, and the desulfurized hydrocarbon oil is sent to the subsequent product separation and stabilization system for treatment via pipeline 28.

[0074] After the desulfurization reaction, the first spent catalyst is transported to the second receiver 30 through pipeline 29 for stripping to remove the oil gas adsorbed on the first spent catalyst. After the hydrocarbon oil is removed, the first spent catalyst is sent to the lock hopper 12 through pipeline 31, and after nitrogen replacement, the high-pressure hydrogen atmosphere is changed to a low-pressure nitrogen atmosphere. The first spent catalyst is sent to the regenerator feeder 15 through pipeline 14. After the first spent catalyst is lifted by the lifting gas, it is sent to the regenerator 18 through pipeline 16 to contact with the oxygen-containing gas to burn off the sulfur and carbon loaded on the first spent catalyst. The first regenerated catalyst obtained after the charring treatment is sent to the regenerator receiver 21 via pipeline 20 for stripping with an inactive gas medium, and then sent to the lock hopper 12 via pipeline 22 to change from a low-pressure oxygen-containing environment to a high-pressure hydrogen-containing environment. The first regenerated catalyst after gas replacement is transported to the desulfurization reactor reducer 33 via pipeline 23 for reduction. The reduced first regenerated catalyst is returned to the desulfurization reactor 27 via pipeline 34 to continue to participate in the selective desulfurization reaction of the benzene-depleted light fraction and the benzene-depleted heavy fraction.

[0075] In another specific embodiment of the present invention, the method for treating hydrocarbon oil of the present invention can also make the debenzenization reactor and the desulfurization reactor share a filter, such as Figure 2 As shown, the upper portion of the desulfurization reactor 27 is provided with a debenzenized hydrocarbon oil inlet for the debenzenized hydrocarbon oil to enter.

[0076] The benzene-rich intermediate fraction is sent to the debenzenization reactor 7 via pipeline 4 for debenzenization reaction. The material after the debenzenization reaction is separated from the second catalyst to be regenerated in the settling separation section at the top of the debenzenization reactor to obtain the second hydrocarbon oil after debenzenization and the second catalyst to be regenerated. The second hydrocarbon oil after debenzenization is transported to the top of the desulfurization reactor 27 via pipeline 8, and the second catalyst to be regenerated is still sent to the first receiver 10 via pipeline 9 for stripping, and then transported to the lock hopper 12 via pipeline 11 for subsequent regeneration, stripping and reduction treatment.

[0077] The benzene-poor light fraction and the benzene-poor heavy fraction are respectively sent to the desulfurization reactor 27 through pipeline 3 and pipeline 5 for selective desulfurization reaction. The hydrocarbon oil material and the first catalyst to be regenerated after the desulfurization reaction are separated in the sedimentation separation section at the top of the desulfurization reactor. The first hydrocarbon oil obtained is mixed with the second hydrocarbon oil through pipeline 8 and further separated from the oil agent in the filter at the top of the desulfurization reactor 27, and then sent to the subsequent separation and stabilization system. The separated first catalyst to be regenerated is continuously sent to the second receiver 30 through pipeline 29 for stripping, and then transported to the lock hopper 12 through pipeline 31 for subsequent regeneration, stripping and reduction treatment.

[0078] The present invention is further described in detail by way of examples. The raw materials used in the examples can be obtained through commercial sources.

[0079] The first catalyst for desulfurization reaction and the second catalyst for debenzenization reaction used in the examples are both FCAS series catalysts, which are commercially available products produced by Nanjing Catalyst Company, with zinc oxide, silica and aluminum oxide as carriers and Ni as the active component.

[0080] The whole-fraction catalytic gasoline, benzene-rich gasoline raw material A and benzene-poor gasoline raw material B used in the embodiment are from Tianjin Petrochemical Company, wherein the gasoline raw material A and the gasoline raw material B are the benzene-rich fraction and the benzene-poor fraction obtained by fractionation of the whole-fraction catalytic gasoline, respectively. The properties of the whole-fraction catalytic gasoline, the gasoline raw material A and the gasoline raw material B are shown in Table 1, and the whole-fraction gasoline can be separated into 13% by weight of the gasoline raw material A and 87% by weight of the gasoline raw material B.

[0081] Table 1 Gasoline raw material properties

[0082]

[0083]

[0084] Example 1

[0085] The test of Example 1 was carried out Figure 1 The test was carried out on the test device shown in the figure. The whole fraction catalytic gasoline raw material was divided into a benzene-poor light fraction, a benzene-rich middle fraction and a benzene-poor heavy fraction in the fractionation tower, wherein the cutting point temperature between the benzene-rich middle fraction and the benzene-poor light fraction was 60°C, and the cutting point temperature between the benzene-rich middle fraction and the benzene-poor heavy fraction was 95°C. The properties of the whole fraction catalytic gasoline, gasoline raw material A and gasoline raw material B are shown in Table 1.

[0086] The benzene-rich intermediate fraction (gasoline feedstock A) is introduced into a debenzenization reactor to carry out a hydrogenation saturation reaction of benzene with a first catalyst, and the reacted materials and the catalyst are separated from the oil agent in a sedimentation separation section and a filter at the top of the debenzenization reactor to obtain a first hydrocarbon oil and a first regenerated catalyst; the first regenerated catalyst is sent to a regenerator for regeneration to obtain a first regenerated catalyst, and the first regenerated catalyst is sent to a first reducer for reduction, and then the reduced first regenerated catalyst is returned to the debenzenization reactor;

[0087] A benzene-poor light fraction and a benzene-poor heavy fraction (gasoline feedstock B) are introduced into a desulfurization reactor to contact with a second catalyst for a desulfurization reaction. The materials and catalyst after the reaction are separated from the oil agent in a sedimentation separation section and a filter at the top of the desulfurization reactor to obtain a second hydrocarbon oil and a second catalyst to be regenerated; the second catalyst to be regenerated is sent to a regenerator for regeneration to obtain a second regenerated catalyst, and the second regenerated catalyst is sent to a second reducer for reduction, and then the reduced second regenerated catalyst is returned to the desulfurization reactor.

[0088] The conditions for implementing the hydrogenation saturation reaction and the desulfurization reaction, as well as the regeneration and reduction conditions of the first spent catalyst and the second spent catalyst, respectively, are shown in Table 2.

[0089] Embodiment 2-3

[0090] The experiments of Examples 2 to 3 were carried out Figure 1 The test apparatus shown in the figure is used, which differs from Example 1 in that:

[0091] The conditions for the introduction of the benzene-rich middle fraction (gasoline feedstock A) into the debenzenization reactor to carry out the hydrogenation saturation reaction of benzene with the first catalyst are different;

[0092] The conditions for the desulfurization reaction when the benzene-poor light fraction and the benzene-poor heavy fraction (gasoline feedstock B) are introduced into the desulfurization reactor and contacted with the second catalyst are different.

[0093] The reaction conditions of the hydrogenation saturation reaction part and the desulfurization reaction part of Examples 2 to 3 and the regeneration conditions of the first spent catalyst and the second spent catalyst are shown in Table 2.

[0094] Example 4

[0095] The test of Example 4 was carried out Figure 2 The test apparatus shown in the figure is used, which differs from Example 1 in that:

[0096] The benzene-rich middle fraction (gasoline feedstock A) is introduced into a debenzenization reactor to carry out a hydrogenation saturation reaction of benzene with a first catalyst, the reaction temperature is 400° C., the molar ratio of hydrogen donor to gasoline feedstock is 4.4, and the reacted materials and the catalyst are separated in a sedimentation separation section at the top of the debenzenization reactor to obtain a first hydrocarbon oil and a first spent catalyst;

[0097] A benzene-poor light fraction and a benzene-poor heavy fraction (gasoline feedstock B) are introduced into a desulfurization reactor to contact with a second catalyst for a desulfurization reaction at a reaction temperature of 440°C. The materials and the catalyst after the desulfurization reaction are separated in a sedimentation separation section at the top of the desulfurization reactor to obtain a second hydrocarbon oil and a second catalyst to be regenerated. The second hydrocarbon oil and the first hydrocarbon oil from the debenzenization reactor are further separated by an oil agent in a filter at the top of the desulfurization reactor to obtain a mixed hydrocarbon oil.

[0098] The reaction conditions during the hydrogenation saturation reaction and the desulfurization reaction in Example 4 and the regeneration conditions of the first spent catalyst and the second spent catalyst are shown in Table 2.

[0099] Table 2 Example reaction conditions and product properties

[0100]

[0101] According to Table 2, it can be seen that the catalyst of the present invention has both desulfurization and hydrogenation saturation functions, and can achieve desulfurization of benzene-poor gasoline and hydrogenation saturation of benzene-rich gasoline.

[0102] The benzene-rich fraction after hydrodebenzenization and the benzene-poor fraction (benzene-poor light fraction and benzene-poor heavy fraction) after desulfurization are directly mixed (weight ratio of about 13:87) as refined hydrocarbon oil.

[0103] Comparative Example 1

[0104] With full-fraction catalytic gasoline as raw material, the full-fraction catalytic gasoline and the hydrogen donor enter the desulfurization reactor, contact with the second catalyst of the desulfurization reactor for desulfurization reaction, and obtain the reaction product and the second regenerated catalyst; the second regenerated catalyst is sent to the regenerator through the pipeline for regeneration to obtain the second regenerated catalyst; then the second regenerated catalyst is reduced in the reducing gas, and the reduced second catalyst is returned to the desulfurization reactor to continue to participate in the reaction. The implementation conditions of the desulfurization reaction and the conditions of catalyst regeneration and reduction are shown in Table 3.

[0105] Comparative Example 2

[0106] Using full-fraction catalytic gasoline as a raw material, the full-fraction catalytic gasoline and a hydrogen donor enter a debenzene reactor to contact the first catalyst for a hydrogenation saturation reaction of benzene, separate the reacted material and the first regenerated catalyst, send the first regenerated catalyst to a regenerator for regeneration to obtain a first regenerated catalyst, send the first regenerated catalyst to a first reducer for reduction, and then return the reduced first regenerated catalyst to the debenzene reactor. The implementation conditions of the hydrogenation saturation reaction and the conditions for catalyst regeneration and reduction are shown in Table 3.

[0107] Table 3 Comparative Example Reaction Conditions and Product Properties

[0108]

[0109]

[0110] From the data in Table 3, it can be seen that when the whole-fraction gasoline is used as a raw material for desulfurization reaction in a desulfurization reactor, the benzene content in the product is still relatively high, while when the whole-fraction gasoline is introduced into a debenzenization reactor for hydrogenation and saturation, the sulfur and benzene contents in the product are very low. However, the olefins in the whole-fraction gasoline are almost all saturated, the loss of aromatics is also very large, the octane number loss is large, and the hydrogen consumption is very high, resulting in poor economic efficiency.

[0111] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0112] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0113] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A method for treating hydrocarbon oil, characterized in that: The following steps are involved: (1) fractionating a hydrocarbon oil feedstock to obtain a benzene-poor light fraction, a benzene-poor heavy fraction, and a benzene-rich middle fraction; the initial distillation point of the benzene-rich middle fraction is any temperature between 55 and 70° C., and the final distillation point is any temperature between 90 and 130° C.; (2) contacting the benzene-depleted light fraction and / or the benzene-depleted heavy fraction and a first hydrogen donor with a first catalyst in a desulfurization reactor and performing a desulfurization reaction under selective desulfurization conditions to obtain a first hydrocarbon oil and a first spent catalyst; (3) contacting the benzene-rich middle fraction and the second hydrogen donor with a second catalyst in a debenzenization reactor and performing a hydrogenation reaction under hydrogenation reaction conditions to convert benzene into cyclohexane to obtain a second hydrocarbon oil and a second spent catalyst; (4) The first catalyst to be regenerated and the second catalyst to be regenerated are subjected to oxygen-containing charring, stripping and reduction in sequence to obtain a first regenerated catalyst and a second regenerated catalyst, and the first regenerated catalyst is returned to the desulfurization reactor for a selective desulfurization reaction, and the second regenerated catalyst is returned to the debenzenization reactor for a hydrogenation reaction.

2. The method according to claim 1, wherein: The hydrocarbon oil feedstock is selected from one or more of catalytic cracking gasoline, catalytic pyrolysis gasoline and reforming gasoline; the sulfur content of the hydrocarbon oil feedstock is 10 to 5000 μg / g, and the mass percentage of benzene in the hydrocarbon oil feedstock is 0.7 to 10%; Preferably, the sulfur content in the hydrocarbon oil feedstock is 30 to 3000 μg / g, and the mass percentage of benzene in the hydrocarbon oil feedstock is 0.8 to 5%; Preferably, the fractionation pressure during the fractionation is 0.1 to 1.0 MPa, preferably 0.1 to 0.5 MPa.

3. The method according to claim 1, wherein: The first catalyst and the second catalyst each include a carrier and a metal active component; based on the weight of the carrier, the carrier includes 20 to 85 wt% of zinc oxide, 10 to 75 wt% of aluminum oxide and 5 to 70 wt% of silica; Based on the weight of the first catalyst and the second catalyst, the content of the metal active component in the first catalyst and the second catalyst is 5 to 30 wt % respectively; The active metal component is selected from one or more of cobalt, nickel, iron, manganese, copper, molybdenum, tungsten, silver, tin and vanadium.

4. The method according to claim 1, wherein: The first hydrogen donor and the second hydrogen donor are independently selected from one or more of hydrogen, a mixed gas containing hydrogen and a hydrogen donor; the hydrogen donor is selected from one or more of tetralin, decalin and dihydroindene; Preferably, the volume fraction of hydrogen in the first hydrogen donor and the second hydrogen donor is independently 50-100%.

5. The method according to claim 1, wherein: The first catalyst and the second catalyst each have an average particle size of 20 to 200 μm and an attrition index of 2.0 to 8.0% independently; Preferably, the first catalyst and the second catalyst each have an average particle size of 40 to 100 μm and an attrition index of 3.0 to 6.0%.

6. The method according to claim 1, wherein: The conditions of the desulfurization reaction include: a reaction temperature of 300-480° C., a reaction pressure of 0.1-5.0 MPa, a volume ratio of the first hydrogen donor to the benzene-depleted light fraction and / or the benzene-depleted heavy fraction of (10-200):1, and a weight hourly space velocity of the benzene-depleted light fraction and / or the benzene-depleted heavy fraction of 0.5-20 h -1 ; Preferably, in the desulfurization reactor, the reaction temperature is 350-450°C, the reaction pressure is 0.5-3.5 MPa, the volume ratio of the first hydrogen donor to the benzene-depleted light fraction and / or the benzene-depleted heavy fraction is (20-100):1, and the weight hourly space velocity of the benzene-depleted light fraction and / or the benzene-depleted heavy fraction is 1.5-10h -1 .

7. The method according to claim 1, wherein: The conditions of the hydrogenation reaction include: a reaction temperature of 150-450° C., a reaction pressure of 0.5-8.0 MPa, a volume ratio of the second hydrogen donor to the benzene-rich middle distillate of (100-2000):1, and a weight hourly space velocity of the benzene-rich middle distillate of 0.2-10 h -1 ; Preferably, the reaction temperature of the hydrogenation reaction is 250-400° C., the reaction pressure is 1.5-3.5 MPa, the volume ratio of the second hydrogen donor to the benzene-rich middle distillate is (300-1000):1, and the weight hourly space velocity of the benzene-rich middle distillate is 1.5-5 h -1 .

8. The method according to claim 1, wherein: The method further comprises: preheating the benzene-depleted light fraction and / or the benzene-depleted heavy fraction and the first hydrogen donor to 300-500° C. before performing the desulfurization reaction; and The benzene-rich middle fraction and the second hydrogen donor are preheated to 150-400° C. before the hydrogenation reaction.

9. The method according to claim 1, wherein: The oxygen-containing coking is carried out in the presence of an oxygen-containing gas, and the conditions for the oxygen-containing coking include: a temperature of 300 to 800° C. and a pressure of 0.1 to 3.0 MPa; preferably, a temperature of 350 to 600° C. and a pressure of 0.1 to 1.0 MPa; The oxygen-containing gas is selected from one of air, a mixed gas of oxygen and nitrogen, and a mixed gas of air and nitrogen; the volume fraction of oxygen in the oxygen-containing gas is 5 to 50%; The medium used in the stripping is selected from nitrogen and / or CO2; Preferably, the reduction of the first catalyst to be regenerated and the second catalyst to be regenerated is performed in a reducing gas atmosphere; the reducing gas is hydrogen or a mixed gas containing hydrogen; the volume fraction of hydrogen in the mixed gas containing hydrogen is 50-100%; Preferably, the reduction conditions include: a reduction temperature of 300 to 480° C. and a reduction pressure of 0.1 to 10 MPa; Preferably, the reduction temperature is 350-450° C., and the reduction pressure is 0.5-5 MPa.

10. The method according to claim 1, wherein: The method further comprises: mixing the first hydrocarbon oil and the second hydrocarbon oil to obtain a refined hydrocarbon oil.

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