A method of treating a hydrocarbon oil

Abstract

The present application relates to a method for treating hydrocarbon oil, comprising fractionating a gasoline feedstock to obtain a benzene-lean light fraction, a benzene-lean heavy fraction and a benzene-rich intermediate fraction; then contacting the benzene-lean light fraction and / or the benzene-lean heavy fraction and a first hydrogen donor with a first catalyst in a desulfurization reactor under selective desulfurization conditions to perform a desulfurization reaction, and contacting the benzene-rich intermediate fraction and a second hydrogen donor with a second catalyst in a benzene saturation reactor under hydrogenation reaction conditions to convert benzene into cyclohexane. The present application realizes the hydrogenation saturation of benzene in the benzene-rich fraction while achieving high selectivity and deep desulfurization of the benzene-lean fraction with little octane loss, thereby reducing the benzene content in the refined product. The hydrocarbon oil after hydrofining can be used as a blending component to produce clean gasoline with low benzene content and low sulfur content.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of petrochemical industry, and particularly relates to a method for treating hydrocarbon oil. BACKGROUND

[0002] In recent years, environmental protection regulations on automobile exhaust emission are becoming increasingly strict, and the requirements for benzene content in gasoline are also increasingly high in the world. The demand for clean oil products with low benzene content is increasingly obvious. The current implemented national VI gasoline quality standard GB 17930-2016 stipulates that the volume fraction of benzene in gasoline is not greater than 0.8%, and stipulates that the sulfur content in gasoline is below 10 micrograms per gram. Since benzene has strong carcinogenic effect, the benzene content in gasoline may be further reduced in future quality specifications.

[0003] The main sources of catalytic gasoline pool include catalytic cracking gasoline, reforming gasoline, alkylated oil, 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 the qualification of the benzene and sulfur content in the gasoline pool. Moreover, reforming gasoline as a high octane component of the gasoline pool must also strictly control the benzene content therein before blending.

[0004] CN101451076A discloses a method for reducing the benzene content in gasoline. The method performs transalkylation reaction of gasoline or benzene-rich fraction in gasoline with multi-alkyl benzene raw material under the action of a solid acid catalyst, which can significantly reduce the benzene content in gasoline without octane loss, gasoline yield loss, and subsequent separation.

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

[0006] The method for reducing the benzene content in hydrocarbon oil can adopt alkylation process, and can also adopt hydrogenation method to hydrogenate and saturate the benzene-rich fraction. For example, the Bensat process developed by UOP Company can treat the benzene-rich fraction of reforming generated oil. The benzene in the benzene-rich fraction is selectively hydrogenated and saturated into cyclohexane on a high-selectivity fixed-bed catalyst. The process only needs slightly more than stoichiometric hydrogen, but needs to use noble metal Pt as the catalyst, which has high cost.

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

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

[0009] To achieve the above-mentioned purpose, the first aspect of the present application provides a method for treating hydrocarbon oil, comprising the following steps:

[0010] (1) fractionating a hydrocarbon oil raw material to obtain a benzene-lean light fraction, a benzene-lean heavy fraction and a benzene-rich middle fraction; the initial boiling point of the benzene-rich middle fraction is any temperature between 55-70℃, and the final boiling point is any temperature between 90-130℃;

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

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

[0013] (4) sequentially carrying out oxygen-containing calcination, stripping and reduction on the first spent catalyst and the second spent catalyst respectively to obtain a first regenerated catalyst and a second regenerated catalyst, and returning the first regenerated catalyst to the desulfurization reactor to carry out a selective desulfurization reaction, and returning the second regenerated catalyst to the benzene conversion reactor to carry out a hydrogenation reaction.

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

[0015] Optionally, the fractionation pressure during fractionation is 0.1-1.0MPa, preferably 0.1-0.5MPa.

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

[0017] Optionally, each of the first hydrogen donor and the second hydrogen donor is independently selected from one or more of hydrogen gas, a hydrogen-containing mixed gas and a hydrogen donor; the hydrogen donor is selected from one or more of tetrahydro naphthalene, decahydro naphthalene and dihydro indene; preferably, the volume fraction of hydrogen gas in each of the first hydrogen donor and the second hydrogen donor is independently 50-100%.

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

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

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

[0021] Optionally, the method further comprises: preheating the benzene-lean light fraction and / or the benzene-lean 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.

[0022] Optionally, the oxygen-containing charring is carried out in the presence of an oxygen-containing gas, the conditions of the oxygen-containing charring 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%; the medium used in the stripping is selected from nitrogen and / or CO2.

[0023] Optionally, the reduction of each of the first spent catalyst and the second spent catalyst is carried out 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 conditions of the reduction include: a reduction temperature of 300-480°C and a reduction pressure of 0.1-10 MPa; preferably, a reduction temperature of 350-450°C and a reduction pressure of 0.5-5 MPa.

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

[0026] Through the above technical solutions, the present application realizes the deep desulfurization of the benzene-lean fraction with high selectivity and low octane loss, and the hydrogenation saturation of benzene in the benzene-rich fraction, thereby reducing the content of benzene in the refined product. The hydrocarbon oil after the hydrofining can be used as a blending component to produce clean gasoline with low benzene content and low sulfur content.

[0027] Other features and advantages of the present application will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

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

[0029] Figure 1 is a flowchart of an embodiment of the method for treating hydrocarbon oil provided by the present application.

[0030] Figure 2 This is a schematic flowchart of another embodiment of the method for processing hydrocarbon oil provided by the present invention.

[0031] Explanation of reference numerals in the attached figures

[0032] 1. Pipeline 2. Distillation Tower 3. Pipeline

[0033] 4 pipelines, 5 pipelines, 6 pipelines

[0034] 7. Benzene Removal Reactor; 8. Pipeline; 9. Pipeline

[0035] 10 First receiver 11 Pipeline 12 Locking 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 pipelines Detailed Implementation

[0044] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

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

[0046] (1) The hydrocarbon oil feedstock is fractionated to obtain a light fraction leaning against benzene, a heavy fraction leaning against benzene, and a middle fraction rich in benzene; the initial boiling point of the middle fraction rich in benzene is any temperature between 55 and 70°C, and the final boiling point is any temperature between 90 and 130°C.

[0047] (2) The light fraction of the lean benzene and / or the heavy fraction of the lean benzene and the first hydrogen donor are contacted with the first catalyst in a desulfurization reactor and desulfurized under selective desulfurization conditions to obtain the first hydrocarbon oil and the first catalyst to be generated.

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

[0049] (4) sequentially performing oxygen-containing coke burning, stripping and reduction on the first spent catalyst and the second spent catalyst respectively to obtain a first regenerated catalyst and a second regenerated catalyst, and returning the first regenerated catalyst to the desulfurization reactor to perform a selective desulfurization reaction, and returning the second regenerated catalyst to the debenznization reactor to perform a hydrogenation reaction.

[0050] By the above technical solution, the benzene-rich intermediate fraction obtained by fractionating the whole fraction gasoline is subjected to a hydrogenation saturation reaction to remove benzene and sulfur therefrom, and the benzene-lean light fraction and the benzene-lean heavy fraction are subjected to a desulfurization reaction to remove sulfur therefrom, so that the benzene in the benzene-rich fraction is subjected to hydrogenation saturation while the benzene-lean fraction is subjected to deep desulfurization with high selectivity and little loss of octane number, thereby reducing the content of benzene in the refined product, and the hydrocarbon oil after the hydrogenation refining can be used as a blending component to produce clean gasoline with low benzene content and low sulfur content. Moreover, the selective adsorption desulfurization and the deep benzene hydrogenation are coupled, thereby reducing the investment and operation cost of the device.

[0051] The catalyst after the desulfurization reaction can be regenerated by contacting with an oxygen-containing gas and then reduced by hydrogen and returned to the desulfurization reactor for continuous use, and the deactivated catalyst after the hydrogenation debenznization reaction can be regenerated by contacting with an oxygen-containing gas and then reduced by hydrogen and used for the desulfurization reaction and the debenznization reaction.

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

[0053] The mass fraction of olefins in the hydrocarbon oil raw material is 2-50%, preferably 5-40%, and the mass fraction of aromatic hydrocarbons is more than 20%, preferably more than 30%.

[0054] The final boiling point of the hydrocarbon oil raw material in the present application is below 220°C, preferably below 200°C.

[0055] The fractionating pressure is 0.1-1.0 MPa, preferably 0.1-0.5 MPa.

[0056] In the present application, the full-component gasoline raw material is fractionated in a fractionating column to obtain a benzene-rich fraction (middle fraction) and a benzene-lean fraction (light fraction or heavy fraction or mixture of light and heavy fractions), the initial boiling point of the benzene-rich fraction being 55-70℃ and the final boiling point being 90-130℃.

[0057] The first catalyst and the second catalyst each comprise a carrier and a metal active component; the carrier comprises 20-85wt% of zinc oxide, 10-75wt% of aluminum oxide and 5-70wt% of silica, based on the weight of the carrier; the content of the metal active component in the first catalyst and the second catalyst is 5-30wt% respectively, based on the weight of the first catalyst and the second catalyst respectively; 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 application, the carrier is prepared by beating and mixing, molding, drying and calcining; the active metal component is loaded onto the carrier by impregnation, spraying or the like, followed by drying and calcining to obtain the catalyst.

[0059] In the present application, in order to facilitate fluidization of the first catalyst and the second catalyst, the first catalyst and the second catalyst are preferably microspheres, the average particle size of which is independently 20-200μm, preferably 40-100μm.

[0060] The first hydrogen donor and the second hydrogen donor are each independently selected from one or more of hydrogen, hydrogen-containing mixed gas and hydrogen donor; the hydrogen donor is selected from one or more of tetrahydro naphthalene, decahydro naphthalene and dihydro indene; 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 20-200μm, and the attrition index is 2.0-8.0%; preferably, the average particle size of the first catalyst and the second catalyst is independently 40-100μm, and the attrition index is 3.0-6.0%.

[0062] The desulfurization reaction conditions include a reaction temperature of 300-480℃, a reaction pressure of 0.1-5.0MPa, a volume ratio of the first hydrogen donor to the benzene-lean light fraction and / or the benzene-lean heavy fraction being (10-200):1, and a weight hourly space velocity of the benzene-lean light fraction and / or the benzene-lean heavy fraction being 0.5-20h -1; preferably, in the desulfurization reactor, the reaction temperature is 350-450 DEG C, the reaction pressure is 0.5-3.5 MPa, the volume ratio of the first hydrogen donor to the light fraction of the benzene-lean fraction and / or the heavy fraction of the benzene-lean fraction is (20-100):1, and the weight hourly space velocity of the light fraction of the benzene-lean fraction and / or the heavy fraction of the benzene-lean fraction is 1.5-10 h -1 The above desulfurization reaction conditions can not only realize deep desulfurization of the benzene-lean fraction, but also result in less loss of octane value of the benzene-lean fraction.

[0063] In the present application, the desulfurization reactor and the benzene removal 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: the reaction temperature is 150-450 DEG C, the reaction pressure is 0.5-8.0 MPa, the volume ratio of the second hydrogen donor to the benzene-rich intermediate fraction is (100-2000):1, and the weight hourly space velocity of the benzene-rich intermediate fraction is 0.2-10 h -1 ; preferably, the reaction temperature of the hydrogenation reaction is 250-400 DEG C, the reaction pressure is 1.5-3.5 MPa, the volume ratio of the second hydrogen donor to the benzene-rich intermediate fraction is (300-1000):1, and the weight hourly space velocity of the benzene-rich intermediate fraction is 1.5-5 h -1 Under the above hydrogenation saturation reaction conditions, the sulfur and benzene in the benzene-rich fraction can be removed, while avoiding excessive loss of octane value of the gasoline, and the consumption of the second hydrogen donor is controlled within a relatively reasonable range, which is good in economy.

[0065] The method further comprises: preheating the light fraction of the benzene-lean fraction and / or the heavy fraction of the benzene-lean fraction and the first hydrogen donor to 300-500 DEG C before the desulfurization reaction; and preheating the benzene-rich intermediate fraction and the second hydrogen donor to 150-400 DEG C before the hydrogenation reaction.

[0066] The oxygen-containing charring is carried out in the presence of an oxygen-containing gas, and the conditions of the oxygen-containing charring include: the temperature is 300-800 DEG C, and the pressure is 0.1-3.0 MPa; preferably, the temperature is 350-600 DEG C, and the pressure is 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%; and the medium used for the stripping is selected from nitrogen and / or CO2.

[0067] The reduction of the first and second spent catalysts is respectively carried out in a reducing gas atmosphere; the reducing gas is hydrogen or a hydrogen-containing mixed gas; the hydrogen-containing mixed gas contains hydrogen in a volume fraction of 50-100%.

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

[0069] In the present application, in order to inhibit the temperature rise of the de-benzene reactor, the hydrogenation saturated reaction product can be returned to be mixed with the benzene-rich intermediate fraction, and the mass ratio of the returned hydrogenation refined product to the benzene-rich intermediate fraction is 0.2-5, preferably 0.5-3.

[0070] The method further comprises mixing the first and second hydrocarbon oils to obtain refined hydrocarbon oil.

[0071] In one specific embodiment of the present application, as shown in Figure 1 The benzene-containing hydrocarbon oil raw material enters the middle part of the fractionating column through pipeline 1, and is fractionated to obtain a benzene-lean light fraction, a benzene-rich intermediate fraction and a benzene-lean heavy fraction. The benzene-rich intermediate fraction is preheated, mixed with the second hydrogen donor from pipeline 6 through pipeline 4, and enters the bottom of the de-benzene reactor 7 from the bottom to the top, and contacts the second catalyst in the de-benzene reactor 7 to carry out hydrogenation reaction, so as to convert benzene into cyclohexane. The hydrocarbon oil material after hydrogenation reaction and the second spent catalyst enter the settling separation section and the filter at the top of the de-benzene reactor 7 to carry out oil catalyst separation, and the hydrocarbon oil after de-benzene is sent to the subsequent product separation and stabilization system through pipeline 8 for further treatment.

[0072] The second spent catalyst after hydrogenation reaction is sent to the first receiver 10 through line 9 for stripping to remove the oil gas adsorbed on the second spent catalyst, and the second spent catalyst after removal of hydrocarbon oil is sent to the closed hopper 12 through line 11, and is changed from a high-pressure hydrogen environment to a low-pressure nitrogen environment after replacement by nitrogen gas in the closed hopper 12, and the replaced gas is sent to the combustion furnace for treatment through line 13. The second spent catalyst is sent to the regenerator feeder 15 through line 14, and the second spent catalyst is lifted by lifting gas and sent to the regenerator 18 through line 16 to contact with the oxygen-containing gas, and the oxygen-containing gas is introduced into the regenerator 18 from the bottom of the regenerator 18 through line 17 for regeneration to remove the sulfur and carbon loaded on the second spent catalyst. The sulfur-containing regeneration flue gas is separated at the top of the regenerator 18 and sent to a sulfur production unit or a flue gas treatment unit through line 19. The second regenerated catalyst is sent to the regenerator receiver 21 through line 20 for stripping, and the oxygen carried by the second regenerated catalyst is reduced by a non-active gas medium such as nitrogen and CO2, and then enters the closed hopper 12 through line 22 to change from a low-pressure oxygen-containing environment to a high-pressure hydrogen environment, and the second regenerated catalyst after gas replacement is sent to the debenzolization reactor reducer 24 through line 23 for reduction, and the second regenerated catalyst after reduction is returned to the debenzolization reactor 7 through line 25 to continue to participate in the debenzolization reaction of the benzene-rich middle distillate.

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

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

[0075] In another specific embodiment of the present application, the method for treating hydrocarbon oil of the present application can also share a filter for the desulfurization reactor and the desulfurization reactor, as shown in Figure 2 As shown, the upper portion of the desulfurization reactor 27 is provided with a desulfurized hydrocarbon oil inlet for the hydrocarbon oil after desulfurization.

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

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

[0078] The present application is further described in detail by the following examples. The raw materials used in the examples can be obtained by commercial purchase.

[0079] The first catalyst for desulfurization reaction and the second catalyst for benzene removal reaction used in the examples are both FCAS series catalysts, which are commercially available and produced by Nanjing Catalyst Company, and have zinc oxide, silica and alumina as carrier and Ni as active component.

[0080] The full-range catalytic gasoline, the benzene-rich gasoline feedstock A and the benzene-lean gasoline feedstock B used in the examples and the gasoline feedstock from Tianjin Petrochemical Branch Company are all full-range catalytic gasoline. The benzene-rich gasoline feedstock A and the benzene-lean gasoline feedstock B are obtained by fractionating the full-range catalytic gasoline. The properties of the full-range catalytic gasoline, the benzene-rich gasoline feedstock A and the benzene-lean gasoline feedstock B are shown in Table 1. The full-range gasoline can be fractionated into 13 wt% of the benzene-rich gasoline feedstock A and 87 wt% of the benzene-lean gasoline feedstock B.

[0081] Table 1 Properties of gasoline feedstocks

[0082]

[0083]

[0084] Example 1

[0085] The test of Example 1 was carried out on the test device shown in Figure 1 The full-range catalytic gasoline feedstock was fractionated into a benzene-lean light fraction, a benzene-rich middle fraction and a benzene-lean heavy fraction in a fractionating column. The cut point temperature of the benzene-rich middle fraction and the benzene-lean light fraction was 60°C, and the cut point temperature of the benzene-rich middle fraction and the benzene-lean heavy fraction was 95°C. The properties of the full-range catalytic gasoline, the benzene-rich gasoline feedstock A and the benzene-lean gasoline feedstock B are shown in Table 1.

[0086] The benzene-rich middle fraction (the gasoline feedstock A) was introduced into a benzene removal reactor to carry out benzene hydrogenation saturation reaction with the first catalyst. The reacted material and the catalyst were separated in a settling separation section and a filter at the top of the benzene removal reactor to obtain a first hydrocarbon oil and a first spent catalyst. The first spent catalyst was sent into a regenerator to be regenerated to obtain a first regenerated catalyst, which was then sent into a first reducer to be reduced, and then the reduced first regenerated catalyst was returned to the benzene removal reactor.

[0087] The benzene-lean light fraction and the benzene-lean heavy fraction (the gasoline feedstock B) were introduced into a desulfurization reactor to carry out desulfurization reaction with the second catalyst. The reacted material and the catalyst were separated in a settling separation section and a filter at the top of the desulfurization reactor to obtain a second hydrocarbon oil and a second spent catalyst. The second spent catalyst was sent into a regenerator to be regenerated to obtain a second regenerated catalyst, which was then sent into a second reducer to be reduced, and then the reduced second regenerated catalyst was returned to the desulfurization reactor.

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

[0089] Examples 2-3

[0090] The test in Examples 2-3 was performed on the test apparatus shown in Figure 1 with the difference from Example 1 being that:

[0091] The conditions for the hydrogenation saturation reaction of benzene by introducing the benzene-rich middle distillate (gasoline feed A) into the benzene removal reactor with the first catalyst were different;

[0092] The conditions for the desulfurization reaction by introducing the benzene-lean light distillate and the benzene-lean heavy distillate (gasoline feed B) into the desulfurization reactor with the second catalyst were different.

[0093] The conditions for the hydrogenation saturation reaction, the desulfurization reaction, and the conditions for the regeneration, reduction, respectively, of the first spent catalyst and the second spent catalyst in Examples 2-3 are shown in Table 2.

[0094] Example 4

[0095] The test in Example 4 was performed on the test apparatus shown in Figure 2 with the difference from Example 1 being that:

[0096] The benzene-lean light distillate and the benzene-lean heavy distillate (gasoline feed B) were introduced into the desulfurization reactor with the second catalyst to perform the desulfurization reaction, the reaction temperature was 440°C, and the desulfurized reaction material and the catalyst were separated in the settling separation section at the top of the desulfurization reactor to obtain the second hydrocarbon oil and the second spent catalyst; the second hydrocarbon oil and the first hydrocarbon oil from the benzene removal reactor were further separated in the filter at the top of the desulfurization reactor to obtain the mixed hydrocarbon oil.

[0097] The benzene-lean light distillate and the benzene-lean heavy distillate (gasoline feed B) were introduced into the desulfurization reactor with the second catalyst to perform the desulfurization reaction, the reaction temperature was 440°C, and the desulfurized reaction material and the catalyst were separated in the settling separation section at the top of the desulfurization reactor to obtain the second hydrocarbon oil and the second spent catalyst; the second hydrocarbon oil and the first hydrocarbon oil from the benzene removal reactor were further separated in the filter at the top of the desulfurization reactor to obtain the mixed hydrocarbon oil.

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

[0099] Table 2 Reaction conditions and product properties in Examples

[0100]

[0101] According to Table 2, the catalyst of the present application has the functions of desulfurization and hydrogenation saturation, and can realize desulfurization of the lean benzene gasoline and hydrogenation saturation of the rich benzene gasoline.

[0102] The material after the benzene in the rich benzene fraction is removed by hydrogenation is directly mixed with the material after the lean benzene fraction (the light fraction of the lean benzene and the heavy fraction of the lean benzene) is desulfurized (weight ratio is about 13:87) to serve as refined hydrocarbon oil.

[0103] Comparative Example 1

[0104] The full-range catalytic gasoline is used as raw material, and the full-range catalytic gasoline and the hydrogen donor enter a desulfurization reactor to contact with a second catalyst to perform a desulfurization reaction, and a reaction product and a second spent catalyst are obtained; the second spent catalyst is sent to a regenerator for regeneration to obtain a second regenerated catalyst; then the second regenerated catalyst is reduced in a 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] The full-range catalytic gasoline is used as raw material, and the full-range catalytic gasoline and the hydrogen donor enter a desulfurization reactor to contact with a second catalyst to perform a desulfurization reaction, and a reaction product and a second spent catalyst are obtained; the second spent catalyst is sent to a regenerator for regeneration to obtain a second regenerated catalyst; then the second regenerated catalyst is reduced in a 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.

[0107] Table 3 Reaction conditions and product properties of comparative examples

[0108]

[0109]

[0110] As can be seen from the data in Table 3, the content of benzene in the product is still high when the full-range gasoline is used as raw material to perform a desulfurization reaction in a desulfurization reactor, and the contents of sulfur and benzene in the product are both very low when the full-range gasoline is introduced into a desulfurization reactor to perform hydrogenation saturation, however, the olefins in the full-range gasoline are almost all saturated, the loss of aromatic hydrocarbons is also very large, the octane number loss is large, and the hydrogen consumption is very high, and the economy is poor.

[0111] The preferred embodiments of the present application are described in detail above, but the present application is not limited to the specific details in the above-described embodiments, and various simple modifications can be made to the technical solutions of the present application within the technical concept of the present application, and these simple modifications all belong to the protection scope of the present application.

[0112] It should also be noted that any technically feasible combination of the various technical features described in the above embodiments is possible, provided that there is no contradiction. In order to avoid unnecessary repetition, the present application will not describe each possible combination.

[0113] Furthermore, any combination of the various embodiments of the present application is possible, provided that there is no contradiction with the idea of the present application, which should also be considered as disclosed by the present application.

Claims

1. A method of treating a hydrocarbon oil, characterized by, The method comprises the following steps: (1) fractionating a hydrocarbon oil feedstock to obtain a benzene-lean light fraction, a benzene-lean heavy fraction and a benzene-rich middle fraction; the benzene-rich middle fraction has an initial boiling point of any temperature between 55 and 70℃ and a final boiling point of any temperature between 90 and 130℃; (2) contacting the benzene-lean light fraction and / or the benzene-lean heavy fraction and a first hydrogen donor with a first catalyst in a desulfurization reactor under selective desulfurization conditions to perform a desulfurization reaction and obtain a first hydrocarbon oil and a first spent catalyst; (3) contacting the benzene-rich middle fraction and a second hydrogen donor with a second catalyst in a benzene removal reactor under hydrogenation reaction conditions to perform a hydrogenation reaction to convert benzene into cyclohexane, and obtain a second hydrocarbon oil and a second spent catalyst; (4) sequentially performing oxygen-containing calcination, stripping and reduction on the first spent catalyst and the second spent catalyst respectively to obtain a first regenerated catalyst and a second regenerated catalyst, and returning the first regenerated catalyst to the desulfurization reactor to perform a selective desulfurization reaction and returning the second regenerated catalyst to the benzene removal reactor to perform a hydrogenation reaction; The first catalyst and the second catalyst each comprise a carrier and a metal active component; the carrier comprises 20-85wt% of zinc oxide, 10-75wt% of aluminum oxide and 5-70wt% of silica, based on the weight of the carrier; the active metal component is selected from one or more of cobalt, nickel, iron, manganese, copper, molybdenum, tungsten, silver, tin and vanadium.

2. The method of claim 1, wherein, The hydrocarbon oil feedstock is selected from one or more of catalytic cracking gasoline, catalytic cracking gasoline and reforming gasoline; the sulfur content of the hydrocarbon oil feedstock is 10-5000μg / g, and the mass percentage of benzene in the hydrocarbon oil feedstock is 0.7-10%; The fractionation pressure during the fractionation is 0.1-1.0 MPa.

3. The method of claim 2, wherein, The sulfur content of the hydrocarbon oil feedstock is 30-3000μg / g, and the mass percentage of benzene in the hydrocarbon oil feedstock is 0.8-5%; The fractionation pressure during the fractionation is 0.1-0.5 MPa.

4. The method of claim 1, wherein, The content of the metal active component in the first catalyst and the second catalyst is 5-30wt% respectively, based on the weight of the first catalyst and the second catalyst respectively.

5. The method of claim 1, wherein, The first hydrogen donor and the second hydrogen donor are each independently selected from one or more of hydrogen, hydrogen-containing mixed gas and hydrogen donor; the hydrogen donor is selected from one or more of tetrahydro naphthalene, decahydro naphthalene and dihydro indene; The volume fraction of hydrogen in the first hydrogen donor and the second hydrogen donor is independently 50-100% respectively.

6. The method of claim 1, wherein, The average particle size of the first catalyst and the second catalyst is independently 20-200μm, and the attrition index is 2.0-8.0%.

7. The method of claim 6, wherein, The average particle size of the first catalyst and the second catalyst is independently 40-100μm, and the attrition index is 3.0-6.0%.

8. The method of claim 1, wherein, The conditions of the desulfurization reaction include: the reaction temperature is 300-480℃, the reaction pressure is 0.1-5.0 MPa, the volume ratio of the first hydrogen donor to the light fraction of the benzene-lean fraction and / or the heavy fraction of the benzene-lean fraction is (10-200):1, the weight hourly space velocity of the light fraction of the benzene-lean fraction and / or the heavy fraction of the benzene-lean fraction is 0.5-20 h -1 .

9. The method of claim 8, wherein, The desulfurization reactor has a reaction temperature of 350-450 ℃, a reaction pressure of 0.5-3.5 MPa, and a volume ratio of the first hydrogen donor to the light fraction of the benzene-lean fraction and / or the heavy fraction of the benzene-lean fraction of (20-100):1, and a weight hourly space velocity of the light fraction of the benzene-lean fraction and / or the heavy fraction of the benzene-lean fraction of 1.5-10 h -1 .

10. The method of 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 intermediate fraction of (100-2000): 1, and a weight hourly space velocity of the benzene-rich intermediate fraction of 0.2-10 h -1 .

11. The method of claim 10, wherein, The reaction temperature of the hydrogenation reaction is 250-400 ℃, the reaction pressure is 1.5-3.5 MPa, the volume ratio of the second hydrogen donor to the benzene-rich intermediate fraction is (300-1000): 1, and the weight hourly space velocity of the benzene-rich intermediate fraction is 1.5-5 h -1 .

12. The method of claim 1, wherein, The method further comprises: preheating the benzene-lean light fraction and / or the benzene-lean heavy fraction and the first hydrogen donor to 300-500℃ before performing the desulfurization reaction; and The benzene-rich intermediate fraction and the second hydrogen donor are preheated to 150-400 DEG C before the hydrogenation reaction.

13. The method of claim 1, wherein, The oxygen-containing charring is carried out in the presence of an oxygen-containing gas, and the conditions of the oxygen-containing charring include a temperature of 300-800 DEG C and a pressure of 0.1-3.0 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; and the volume fraction of oxygen in the oxygen-containing gas is 5-50%. The medium used in the stripping is selected from nitrogen and / or CO2. The reduction of each of the first spent catalyst and the second spent catalyst is carried out in a reducing gas atmosphere; the reducing gas is hydrogen or a mixed gas containing hydrogen; and the volume fraction of hydrogen in the mixed gas containing hydrogen is 50-100%. The conditions of the reduction include a reduction temperature of 300-480 DEG C and a reduction pressure of 0.1-10 MPa.

14. The method of claim 13, wherein, The conditions of the oxygen-containing charring include a temperature of 350-600 DEG C and a pressure of 0.1-1.0 MPa. The conditions of the reduction include a reduction temperature of 350-450 DEG C and a reduction pressure of 0.5-5 MPa.

15. The method of 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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