Gasoline preparation device and gasoline preparation method

Abstract

The invention relates to the field of petroleum refining, and discloses a gasoline preparation device and a gasoline preparation method. The device comprises a membrane mixing unit (300), an olefin removal unit (400) and an S-Zorb desulfurization unit (500) which are adjacent in sequence, and a raw oil feeding unit (100) is arranged on a connecting pipeline between the olefin removal unit (400) and the S-Zorb desulfurization unit (500) and used for feeding raw oil into the connecting pipeline. According to the technical scheme, the content of olefin in gasoline can be flexibly adjusted while desulfurization is carried out, octane number loss is reduced, and the gasoline fraction which is low in olefin content and octane number loss and meets the standard is obtained.

Description

[0001] This application is a divisional application of a Chinese patent application with the application number 202110610272.3, the application date of June 1, 2021, and the title of "Gasoline Preparation Device and Gasoline Preparation Method". Technical Field

[0002] The present invention relates to the field of petroleum refining, and specifically relates to a gasoline preparation device and a gasoline preparation method. Background Art

[0004] With the strictness of motor vehicle pollutant emission standards, higher requirements are put forward for multiple indicators such as sulfur content, gasoline olefins, aromatics, benzene, and distillation range. Among them, the volume fraction of olefins in gasoline is required to be lower. Therefore, how to maximize the preservation of octane number while significantly reducing olefins is an important issue faced by the quality upgrade of National VI gasoline.

[0005] The S-Zorb gasoline adsorption desulfurization technology desulfurizes gasoline based on the principle of adsorption. Specifically, this technology uses an adsorbent to adsorb sulfur-containing molecules, removes sulfur atoms from the adsorbed molecules, retains the sulfur atoms on the adsorbent, and at the same time releases the hydrocarbon part in the molecules and returns it to the gasoline. No H2S is generated during the above reaction process, thus avoiding the re-reaction of H2S with olefins to form mercaptans. Compared with the hydrodesulfurization technology, this technology has a better desulfurization effect on thiophene sulfur that is difficult to remove by the hydrotreating process, can achieve the purpose of deep desulfurization, and the olefin content (20 - 30 wt%) of the treated gasoline basically remains unchanged, and the loss of gasoline octane number is small.

[0006] However, the current S-Zorb device has the following problems during operation: The catalytic gasoline contains olefins and a small amount of diolefins. The temperature of the S-Zorb device adsorption desulfurization reaction (≥400 °C) is relatively high, and olefins will polymerize under high-temperature conditions, increasing the dry point of gasoline and reducing the output of gasoline products. In addition, a small amount of diolefins contained in gasoline are extremely easy to polymerize, resulting in coking on the walls of heat exchange equipment (such as raw material heat exchangers, preheating furnaces), reducing the heat exchange efficiency of the equipment and increasing the processing energy consumption. On the other hand, since the volume fraction of olefins in gasoline needs to be reduced to less than 18% (National VI A) or 15% (National VI B), under the current production conditions of the S-Zorb device, the reduction range of gasoline olefins is limited. To meet the olefin content requirements of the National VI standard, it is necessary to significantly reduce the olefin content of the raw material gasoline, that is, the gasoline from the fluid catalytic cracking unit (FCC gasoline), resulting in a reduction in the overall efficiency of the catalytic unit and even the entire refinery unit.

[0007] CN107686745A discloses a light gasoline etherification system and a light gasoline etherification process. The process method includes: mixing methanol and light gasoline in a static mixer, entering a fixed-bed reactor filled with a sulfonic acid series macroporous cation exchange resin catalyst for etherification pre-reaction, and then entering a catalytic distillation column for catalytic distillation deep etherification. Although this process improves the conversion rates of etherifiable C5 and C6, there are problems such as complex process, low total olefin removal rate, and unqualified oxygen content in gasoline.

[0008] CN102839014A discloses a reactor and method for enhancing heavy oil conversion and reducing olefins in gasoline. The method includes designing the riser reactor into a two-stage variable-diameter riser reactor. By using this reactor, the catalyst density and oil-agent contact efficiency in the riser can be increased, and the operating conditions can be controlled to improve the conversion rate of the second-stage heavy oil and further reduce the olefin content in gasoline. This method can increase the catalyst density and oil-agent contact efficiency in the riser, improve the conversion rate of the second-stage heavy oil, and further reduce the olefin content in gasoline. However, the total olefin content in the catalytic gasoline obtained by this method is above 30% by volume, and the content is relatively high.

[0009] CN1488728A discloses a catalytic gasoline aromatization catalyst and its application. Specifically, after adding an appropriate amount of potassium salt aqueous solution to K-type zeolite and binder, it is formed, dried, and calcined to obtain a catalytic gasoline aromatization catalyst. Integrating this catalyst into the FCC gasoline hydrodesulfurization / aromatization combined process technology, the desulfurization rate of FCC gasoline can reach 90%, the olefin saturation rate reaches 51%, the gasoline yield remains basically unchanged, and the anti-knock index loss is 1.7 - 2.0. Although the amount of olefin removal in gasoline in this scheme is large and the octane number loss is small, the aromatic hydrocarbon content in the gasoline obtained thereby will exceed the standard.

[0010] US6083379A discloses a desulfurization process for cracked gasoline. The process includes: dividing the cracked gasoline into light and heavy fractions, where the light fraction is contacted with a catalyst containing a zeolite for aromatization, and the resulting intermediate product is mixed with the heavy fraction. Specifically, the intermediate product is fractionated into an overhead stream containing light olefins and a bottom stream containing aromatic hydrocarbons. Under desulfurization reaction conditions, a part of the bottom stream and a part of the heavy fraction are hydrodesulfurized, and the total octane number of the desulfurized product after mixing with the remaining part of the fractionation bottom, the remaining part of the heavy fraction, and the overhead stream is at least equal to the octane number of the cracked gasoline feed.

[0011] In summary, the existing catalytic cracking gasoline olefin reduction technologies are mostly to improve the olefin content in gasoline components through gasoline etherification, aromatization, isomerization, hydrogenation and deolefination, as well as the catalytic cracking gasoline production process, the activity and selectivity of catalysts and catalytic promoters. The problems of these methods and technologies are as follows: some processes are complex and require large investments; some methods have uncontrollable olefin removal rates, excessive removal amounts, and large octane number losses; some processes have limited olefin reduction and cannot meet gasoline quality standard requirements; and some process technologies are not yet mature and cannot be applied on a large scale in industry. Summary of the invention

[0012] The purpose of the present invention is to meet stricter motor vehicle emission standards, overcome the problems of the prior art such as complicated gasoline preparation process, high investment, low olefin reduction and failure to meet the standards, or too high olefin reduction and excessive octane number loss, and provide two gasoline preparation devices and gasoline preparation methods. The gasoline preparation method is easy to operate, can flexibly adjust the olefin content in gasoline, and obtain gasoline that meets the standards. The device has low investment and is very easy to improve and implement. The olefin content of the obtained gasoline is greatly reduced, and the octane number loss is very small.

[0013] In order to achieve the above-mentioned purpose, the first aspect of the present invention provides a gasoline preparation device, which includes a membrane mixing unit, a deolefination unit and an S-Zorb desulfurization unit connected in sequence, wherein a crude oil feeding unit is provided on the connecting pipeline between the deolefination unit and the S-Zorb desulfurization unit for feeding the crude oil into the connecting pipeline.

[0014] Preferably, the feedstock oil feed unit comprises a feedstock oil delivery pipeline; more preferably, the feedstock oil feed unit comprises a branch pipeline for delivering the feedstock oil to the membrane mixing unit and the connecting pipeline respectively.

[0015] Preferably, a flow regulating valve is provided on the branch pipeline.

[0016] Preferably, the device further comprises: a gas supply unit connected to the crude oil feed unit and the membrane mixing unit; a gas-liquid separation unit arranged after the S-Zorb desulfurization unit; and a fractionation unit arranged after the gas-liquid separation unit.

[0017] Preferably, the S-Zorb desulfurization unit further comprises a heating unit; more preferably, the heating unit is disposed between the deolefination unit and the main body of the S-Zorb desulfurization unit, and is disposed after the branch pipeline.

[0018] Preferably, the membrane mixing unit includes at least one liquid channel for accommodating the feedstock oil or the second desulfurization product and a gas channel for accommodating hydrogen, and the liquid channel and the gas channel are adjacent to each other through a membrane tube having through holes with an average pore size in the nanometer scale; more preferably, the membrane tube is formed of a porous material.

[0019] The second aspect of the present invention provides a gasoline preparation device, which includes an S-Zorb desulfurization unit, a membrane mixing unit, and a deolefination unit connected in sequence, wherein a second desulfurization product feeding unit is connected to the connecting pipeline after the deolefination unit for feeding the second desulfurization product into the connecting pipeline.

[0020] Preferably, the second desulfurization product feeding unit includes a second desulfurization product conveying pipeline; more preferably, the second desulfurization product feeding unit includes a branch pipeline for respectively feeding the second desulfurization product into the membrane mixing unit and the connecting pipeline.

[0021] Preferably, a flow regulating valve is provided on the branch pipeline.

[0022] Preferably, the device further includes: a feedstock oil feeding unit connected to the S-Zorb desulfurization unit; a gas supply unit connected to the feedstock oil feeding unit and the membrane mixing unit;

[0023] a gas-liquid separation unit provided after the deolefination unit; and a fractionation unit provided after the gas-liquid separation unit.

[0024] Preferably, the S-Zorb desulfurization unit further includes a heating unit; more preferably, the heating unit is provided between the feedstock oil feeding unit and the main body of the S-Zorb desulfurization unit.

[0025] Preferably, the membrane mixing unit includes at least one liquid channel for accommodating the feedstock oil or the second desulfurization product and a gas channel for accommodating hydrogen, and the liquid channel and the gas channel are adjacent to each other through a membrane tube having through holes with an average pore size in the nanometer scale; more preferably, the membrane tube is formed of a porous material.

[0026] The third aspect of the present invention provides a gasoline preparation method, wherein this method uses the preparation device described in the first aspect of the present invention and includes the following steps:

[0027] 1) A step of mixing a part of the feedstock oil and hydrogen in the membrane mixing unit;

[0028] 2) A step of subjecting the mixed feedstock oil in step 1) to hydrogenation in the deolefination unit;

[0029] 3) A step of subjecting the first hydrogenation product obtained in step 2) and another part of the feedstock oil fed from the branch pipeline of the feedstock oil feeding unit to desulfurization in the S-Zorb desulfurization unit,

[0030] wherein the part of the feedstock oil accounts for more than 30% by weight of the total weight of the part of the feedstock oil and the other part of the feedstock oil.

[0031] Preferably, the hydrogenation step is carried out in the presence of a hydrogenation catalyst, the hydrogenation catalyst contains a carrier and an active component supported on the carrier, and the carrier contains at least one of alumina, USY and silica, and the active component contains at least two of the metal elements Mo, Ni and Co.

[0032] Preferably, the conditions for hydrogenation include: a pressure of 2.2 - 4 MPa, a temperature of 100 - 200 °C, a liquid hourly space velocity of 0.5 - 12.0 h -1 , and a hydrogen-oil volume ratio of 3 - 60:1; more preferably, the conditions for hydrogenation include: a pressure of 2.5 - 3 MPa, a temperature of 140 - 180 °C, a liquid hourly space velocity of 4 - 8 h -1 , and a hydrogen-oil volume ratio of 10 - 30:1.

[0033] Preferably, the part of the feedstock oil accounts for 50 - 70% by weight of the total weight of the part of the feedstock oil and the other part of the feedstock oil.

[0034] Preferably, the feedstock oil is one or more of catalytic cracking gasoline, coking gasoline and pyrolysis gasoline; more preferably, the feedstock oil is catalytic cracking gasoline.

[0035] Preferably, the distillation range of the feedstock oil is 35 - 210 °C, and the content of olefins in the feedstock oil is 18 - 35% by volume; more preferably, the distillation range of the feedstock oil is 39 - 205 °C, and the content of olefins in the feedstock oil is 18 - 27% by volume.

[0036] Preferably, the olefin content in the prepared gasoline is 18% by volume or less, and the sulfur content is 10 ppm or less; more preferably, the olefin content in the prepared gasoline is 15% by volume or less, and the sulfur content is 8 ppm or less.

[0037] The fourth aspect of the present invention provides a method for preparing gasoline, which uses the preparation device described in the second aspect of the present invention and includes the following steps:

[0038] 1) A step of subjecting the feedstock oil to desulfurization in the S-Zorb desulfurization unit;

[0039] 2) A step of mixing the obtained partial second desulfurized product with hydrogen in the membrane mixing unit and then performing hydrogenation in the deolefination unit;

[0040] 3) A step of mixing the second hydrogenated product obtained in step 2) with another part of the second desulfurized product obtained in step 1),

[0041] wherein the partial second desulfurized product accounts for more than 25% by weight of the total weight of the partial second desulfurized product and the other part of the second desulfurized product.

[0042] Preferably, the hydrogenation step is carried out in the presence of a hydrogenation catalyst, the hydrogenation catalyst contains a carrier and an active component supported on the carrier, and the carrier contains at least one of alumina, USY and silica, and the active component contains at least two of the metal elements Mo, Ni and Co.

[0043] Preferably, the conditions for hydrogenation include: a pressure of 2.2 - 4 MPa, a temperature of 100 - 200 °C, a liquid hourly space velocity of 0.5 - 12.0 h -1 , and a hydrogen - to - oil volume ratio of 3 - 60:1; more preferably, the conditions for hydrogenation include: a pressure of 2.5 - 3 MPa, a temperature of 140 - 180 °C, a liquid hourly space velocity of 4 - 8 h -1 , and a hydrogen - to - oil volume ratio of 10 - 30:1.

[0044] Preferably, the partial second desulfurized product accounts for 50 - 60% by weight of the total weight of the partial second desulfurized product and the other part of the second desulfurized product.

[0045] Preferably, the feedstock oil is one or more of catalytic cracking gasoline, coking gasoline and pyrolysis gasoline; more preferably, the feedstock oil is catalytic cracking gasoline.

[0046] Preferably, the distillation range of the feedstock oil is 35 - 210 °C, and the olefin content in the feedstock oil is 18 - 35% by volume; more preferably, the distillation range of the feedstock oil is 39 - 205 °C, and the olefin content in the feedstock oil is 18 - 27% by volume.

[0047] Preferably, the olefin content in the prepared gasoline is 18% by volume or less, and the sulfur content is 10 ppm or less; more preferably, the olefin content in the prepared gasoline is 15% by volume or less, and the sulfur content is 8 ppm or less.

[0048] Through the above technical solution, the present invention can flexibly adjust the olefin content in gasoline while desulfurizing, and at the same time reduce the octane number loss, obtaining a qualified gasoline fraction with a low olefin content and less octane number loss.

[0049] In addition, by arranging the olefin removal unit before the S-Zorb desulfurization unit, coking of the feed heat exchanger of the S-Zorb desulfurization unit can be effectively prevented, thereby extending the operation cycle of the unit.

[0050] The present invention can be modified on the basis of the existing S-Zorb desulfurization device. At least one olefin removal unit is arranged before or after the original S-Zorb desulfurization unit. By performing olefin removal treatment on part of the feedstock oil or desulfurized product, the olefin content can be reduced while maximizing the retention of the octane number, and finally a gasoline fraction with low sulfur (as low as 4 ppm) and low olefins (as low as less than 15% by volume) can be obtained. The operation cost is lower, the investment is less, and the device modification is easy. Thus, the gasoline production and quality can be improved, and the production cost can be reduced. Description of the Drawings

[0051] Figure 1 is a schematic diagram of a gasoline preparation device in a preferred embodiment of the present invention;

[0052] Figure 2 is a schematic diagram of a gasoline preparation device in another preferred embodiment of the present invention.

[0053] Description of the Reference Numerals

[0054] 100: Feedstock oil feeding unit 200: Gas supply unit

[0055] 300: Membrane mixing unit 400: Olefin removal unit

[0056] 110, 120: Branch pipelines 121: Flow regulating valve

[0057] 500: S-Zorb desulfurization unit 510: Heating unit

[0058] 700: Gas-liquid separation unit 800: Fractionation unit

[0059] 610, 620, 630, 640, 650: Heat exchange units

[0060] A: Feedstock oil A1: Part of the feedstock oil

[0061] A2: Another part of the feedstock oil B: Hydrogen

[0062] B1: Part of the hydrogen B2: Another part of the hydrogen

[0063] C: First hydrogenation product D: Mixed hydrogenation product

[0064] E: First desulfurization product F: First liquid phase

[0065] G, G': Reaction tail gas H, H': Gasoline fraction

[0066] I, I': Dry gas M: Second desulfurized product

[0067] M1: Part of the second desulfurized product M2: Another part of the second desulfurized product

[0068] N: Second hydrogenated product P: Mixed desulfurized and hydrogenated product

[0069] F': Second liquid phase Detailed implementation manners

[0070] In the ranges disclosed herein, the endpoints and any values are not limited to the exact ranges or values. These ranges or values should be understood to include values close to these ranges or values. For numerical ranges, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values, they can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein.

[0071] In the present invention, it should be understood that the orientation or positional relationship indicated by terms such as "center, inner, outer, upper, lower" is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific orientation, as well as a specific orientation structure and operation. Therefore, it cannot be understood as a limitation to the present invention.

[0072] In the present invention, the catalytic cracking gasoline refers to gasoline produced through the catalytic cracking process.

[0073] In the present invention, the coking gasoline refers to gasoline produced through the delayed coking process.

[0074] In the present invention, the pyrolysis gasoline refers to gasoline produced during the process of high-temperature pyrolysis of light hydrocarbons, naphtha, diesel, or vacuum gas oil in the presence of steam to produce ethylene.

[0075] In the present invention, the volume ratio of the gas (such as hydrogen) to the liquid (such as feedstock oil and desulfurized product, etc.) is the ratio at 25°C and 1 standard atmosphere.

[0076] In the present invention, it should be noted that after preparing the gasoline fraction by using the gasoline preparation device and gasoline preparation method of the present invention, the final gasoline product can be obtained by further adding additives, etc. for blending on the basis of the obtained gasoline fraction through conventional devices and methods. The subsequent devices and methods are all common knowledge in the art. To avoid obscuring the main idea of the present invention, the present invention will not describe the subsequent blending steps in detail.

[0077] The first aspect of the present invention provides a device for preparing gasoline, such as Figure 1As shown in the figure, the device includes a membrane mixing unit 300, a de-olefination unit 400, and an S-Zorb desulfurization unit 500 that are connected in sequence. Among them, a feedstock oil feeding unit 100 is provided on the connecting pipeline between the de-olefination unit 400 and the S-Zorb desulfurization unit 500 for feeding the feedstock oil into the connecting pipeline.

[0078] In the present invention, by arranging the membrane mixing unit 300 and the de-olefination unit 400 before the S-Zorb desulfurization unit 500, olefins in part of the feedstock oil can be removed before desulfurization, thereby reducing the olefin content of the obtained gasoline fraction; by feeding another part of the feedstock oil into the connecting pipeline between the de-olefination unit 400 and the S-Zorb desulfurization unit 500, the octane number of the feedstock oil without de-olefination can be retained, thereby controlling the quality of the obtained gasoline fraction.

[0079] Hereinafter, each unit of the gasoline preparation device according to the first aspect of the present invention will be described in detail first.

[0080] In the present invention, the membrane mixing unit 300 is used to mix liquid materials such as feedstock oil with hydrogen so that the two are evenly distributed, thereby controlling the concentration of hydrogen in the subsequent hydro-de-olefination reaction and further improving the effect of the de-olefination reaction.

[0081] Preferably, the membrane mixing unit is a membrane mixer, and the membrane mixer includes at least one liquid channel for accommodating the feedstock oil and a gas channel for accommodating hydrogen. The liquid channel and the gas channel are adjacent through a membrane tube having through holes with an average pore size in the nanometer range. More preferably, the membrane tube is formed of a porous material.

[0082] Preferably, the membrane mixing unit has two concentric tubular channels, one of which is a liquid channel for accommodating liquid materials such as feedstock oil, and the other is a gas channel for accommodating hydrogen, etc. And the liquid channel is inside the gas channel, and the tube wall of the liquid channel (i.e., the inner wall of the gas channel) is the membrane tube having through holes with an average pore size in the nanometer range.

[0083] According to the present invention, the number of the membrane mixing units 300 can be one or more. It can be set according to the processing amount of the feedstock oil and the number of the de-olefination units 400, as long as it can ensure the mixing of the feedstock oil and hydrogen, and there is no particular limitation. Preferably, the number of the membrane mixing units 300 is the same as the number of the de-olefination units 400.

[0084] For example, the number of the membrane mixing units 300 can be 1, 2, 3, 3, 5, etc.

[0085] In the present invention, the olefin removal unit 400 may be various reactors conventional in the art that can remove olefins from the feedstock oil, without particular limitation. As long as the olefins contained in the feedstock oil can react therein to obtain the olefin-removed feedstock oil. For example, the olefin removal unit 400 may be an axial reactor and / or a radial reactor.

[0086] According to the present invention, the number of the olefin removal units 400 provided may be one or more, and can be flexibly set according to the processing amount of the feedstock oil and the olefin removal capacity of a single olefin removal unit 400, without particular limitation.

[0087] For example, the number of the olefin removal units 400 may be 1, 2, 3, 3, 5, etc.

[0088] In the present invention, the S-Zorb desulfurization unit 500 may be various reactors conventional in the art that use the S-Zorb adsorption desulfurization process for desulfurization, without particular limitation. As long as the sulfur contained in the feedstock oil can be adsorbed to obtain the desulfurized feedstock oil. For example, the S-Zorb desulfurization unit 500 may be a moving bed reactor and / or a fluidized bed reactor.

[0089] In addition, in the present invention, there is no particular limitation on the number of the S-Zorb desulfurization units 500, as long as the production requirements can be met. Preferably, the number of the S-Zorb desulfurization units 500 is at least one; more preferably, the number of the S-Zorb desulfurization units 500 is one.

[0090] For example, the number of the -Zorb desulfurization units 500 may be 1, 2, 3, 3, 5, etc.

[0091] Furthermore, according to a preferred embodiment of the present invention, the S-Zorb desulfurization unit 500 further includes a heating unit 510, which is arranged between the olefin removal unit 400 and the body of the S-Zorb desulfurization unit 500, and is arranged after the branch pipeline 120. The heating unit 510 is used to heat the material before entering the S-Zorb desulfurization unit 500, so as to more efficiently achieve desulfurization.

[0092] In the present invention, the heating unit 510 may be various structures commonly used in the art to heat the material containing the feedstock oil, without particular limitation. For example, the heating unit 510 may be a heating furnace.

[0093] In the present invention, the feedstock oil feeding unit 100 may include an oil storage component and various feedstock oil pipelines, power components, valves, etc. that can transport the feedstock oil from the oil storage component to a designated position, without particular limitation. For example, in a preferred embodiment of the present invention, the feedstock oil feeding unit 100 includes an oil storage tank, a feedstock oil pipeline, a pump, and a valve.

[0094] In addition, in order to feed the feedstock oil into the connecting pipeline between the deolefination unit 400 and the S-Zorb desulfurization unit 500, preferably, the feedstock oil pipeline of the feedstock oil feeding unit 100 includes branch pipelines 110 and 120. The branch pipeline 110 can transport a part of the feedstock oil A1 from the oil storage tank to the membrane mixing unit 300; the branch pipeline 120 can transport another part of the feedstock oil A2 from the oil storage tank into the connecting pipeline between the deolefination unit 400 and the S-Zorb desulfurization unit 500.

[0095] In addition, valves for opening and closing and flow regulation can also be provided on the feedstock oil pipeline. For example, preferably, a flow regulating valve 121 is provided on the branch pipeline 120 to regulate the flow rate of another part of the feedstock oil A2 transported from the oil storage tank into the connecting pipeline between the deolefination unit 400 and the S-Zorb desulfurization unit 500, thereby further controlling the weight ratio of the part of the feedstock oil A1 to the another part of the feedstock oil A2 and improving the quality of the obtained gasoline fraction.

[0096] In addition, the gasoline preparation device according to the first aspect of the present invention may further include: a gas supply unit 200, which is connected to the feedstock oil feeding unit 100 and the membrane mixing unit 300 and is used to supply hydrogen to the feedstock oil A and the membrane mixing unit 300; a gas-liquid separation unit 700, which is connected to the S-Zorb desulfurization unit 500 and is arranged behind the S-Zorb desulfurization unit 500 and is used to separate the reaction tail gas G and the first liquid phase F; a fractionation unit 800, which is connected to the gas-liquid separation unit 700 and is arranged behind the gas-liquid separation unit 700 and is used to fractionate the first liquid phase F obtained by gas-liquid separation to obtain a gasoline fraction H.

[0097] In the present invention, the gas supply unit 200 can be various conventional structures in the art that can stably supply gas, without particular limitation. For example, the gas supply unit 200 may include a gas pipeline for gas transportation, a power device such as a pump for providing power, and valves for regulating the flow rate and controlling the opening and closing, so as to supply hydrogen to the feedstock oil feeding unit 100, the membrane mixing unit 300, etc. through the gas pipeline.

[0098] In the present invention, preferably, the gas pipeline of the gas supply unit 200 has a branch pipeline for transporting a part of hydrogen B1 to the pipeline behind the storage tank of the feedstock oil feeding unit 100 to be mixed with the feedstock oil A, and transporting another part of hydrogen B2 to the membrane mixing unit 300 for hydrogenation with a part of the feedstock oil A1.

[0099] In the present invention, the gas-liquid separation unit 700 can be various structures commonly used in the art for separating gas phase and liquid phase, and can be provided with a gas phase outlet and a liquid phase outlet. For example, the gas-liquid separation unit can be a vertical high-pressure separator and / or a horizontal high-pressure separator, without particular limitation, as long as it can separate gas and liquid-phase oil.

[0100] In the present invention, the fractionation unit 800 can be various structures commonly used in the art that can achieve fractionation, as long as it can fractionate the first liquid phase F as needed and separate to obtain a gasoline fraction. For example, the fractionation unit 800 can be a plate column and / or a packed column. In a preferred embodiment of the present invention, the fractionation unit is a plate fractionating column.

[0101] In addition, the gasoline preparation device according to the first aspect of the present invention may further include one or more heat exchange units, various valves, and pipelines for connecting the above-mentioned units to each other. The above-mentioned components are conventional structures in the art and will not be elaborated here.

[0102] In addition, in the present invention, as Figure 1 shown, the gasoline preparation device may further include heat exchange units 610, 620, and 630. The heat exchange units 610, 620, and 630 can be various conventional components in the art that can perform heat exchange, without particular limitation. Preferably, the heat exchange units 610, 620, and 630 are heat exchangers.

[0103] When using a heat exchanger as the heat exchange units 610, 620, and 630, each heat exchange unit can contain one or more groups of heat exchangers, as long as it is set according to the heat exchange requirements.

[0104] Among them, preferably, the heat exchange unit 610 is arranged on the connecting pipeline between the feedstock oil feeding unit 100 and the membrane mixing unit 300 for heating the feedstock oil A to improve the hydrogenation rate of the feedstock oil in the deolefination reaction unit 400.

[0105] Preferably, the heat exchange unit 620 is arranged on the connecting pipeline between the deolefination unit 400 and the S-Zorb desulfurization unit 500, and is arranged after the branch pipeline 120 of the crude oil feed unit 100, and is used to heat the mixed product of the first hydrogenation product C and the crude oil A2, thereby improving the overall working efficiency of the device.

[0106] Preferably, the heat exchange unit 630 is disposed on the connecting pipeline between the S-Zorb desulfurization unit 500 and the gas-liquid separation unit 700, and is used to cool the first desulfurization product E, thereby facilitating an increase in the subsequent gas-liquid separation rate.

[0107] The following, combined Figure 1 , a particularly preferred embodiment of the first aspect of the present invention is described. In a particularly preferred embodiment of the present invention, the gasoline preparation device includes a crude oil feed unit 100, a gas supply unit 200, a membrane mixing unit 300, a deolefination unit 400, an S-Zorb desulfurization unit 500, a gas-liquid separation unit 700, a fractionation unit 800 and three heat exchange units 610, 620, 630. The crude oil feed unit 100 includes an oil storage tank for storing crude oil, a crude oil delivery pipeline for delivering crude oil, and a pump ( Figure 1 ), the crude oil delivery pipeline further includes branch pipelines 110 and 120, the branch pipeline 110 is connected to the membrane mixing unit 300, and the heat exchange unit 610 is arranged on the connecting pipeline between the crude oil feed unit 100 and the membrane mixer 300, the branch pipeline 120 is connected to the connecting pipeline between the deolefination unit 400 and the S-Zorb desulfurization unit 500, and a flow regulating valve 121 is arranged on the branch pipeline 120. The gas supply unit 200 is connected to the crude oil feed unit 100 and the membrane mixing unit 300. Specifically, the gas supply unit 200 sends part of the hydrogen B1 into the pipeline behind the oil storage tank of the crude oil feed unit 100 and before the branch pipeline through the branch gas pipeline, so that part of the hydrogen B1 is mixed with the crude oil A; in addition, another part of the hydrogen B2 is sent to the membrane mixing unit 300 through the branch gas pipeline, thereby further preventing the S-Zorb desulfurization unit 500 from coking. The membrane mixing unit 300 is sequentially connected with the deolefination unit 400, the heat exchange unit 620, the heating unit 510, the S-Zorb desulfurization unit 500, the heat exchange unit 630, the gas-liquid separation unit 700 and the fractionation unit 800.

[0108] According to the present invention, in Figure 1In the preferred embodiment shown, by arranging the olefin removal unit 400 before the S-Zorb desulfurization unit 500, not only can the olefins in the feedstock oil be effectively removed, the sulfur content be reduced, but also the heat exchanger 620, the heating unit 510 and the S-Zorb desulfurization unit 500 can be effectively prevented from coking, the operation cycle of the device can be extended, the operation cost can be reduced, and at the same time, on the basis of maximizing the retention of the octane number, the quality of the obtained gasoline fraction can be improved.

[0109] Next, in conjunction with Figure 2 , the gasoline preparation device of the second aspect of the present invention will be described in detail.

[0110] As Figure 2 shown, the gasoline preparation device described in the second aspect of the present invention includes an S-Zorb desulfurization unit 500, a membrane mixing unit 300 and an olefin removal unit 400 connected in sequence, wherein a second desulfurized product feed unit is connected to the connection pipeline after the olefin removal unit 400 for feeding the second desulfurized product into the connection pipeline.

[0111] In the present invention, by arranging the membrane mixing unit 300 and the olefin removal unit 400 after the S-Zorb desulfurization unit 500, the olefins in part of the second desulfurized product can be removed after desulfurization, thereby reducing the olefin content of the obtained gasoline fraction; by feeding another part of the second desulfurized product into the connection pipeline after the olefin removal unit 400, the octane number in another part of the second desulfurized product without olefin removal can be retained, thereby controlling the quality of the obtained gasoline fraction.

[0112] In the second aspect of the present invention, the S-Zorb desulfurization unit 500, the membrane mixing unit 300 and the olefin removal unit 400 and the number thereof provided can be the same as those of the gasoline preparation device described in the first aspect of the present invention. In order not to obscure the main idea of the present invention, it will not be elaborated here.

[0113] In addition, according to a preferred embodiment of the present invention, the S-Zorb desulfurization unit 500 further includes a heating unit 510, which is arranged between the feedstock oil inlet unit 100 and the body of the S-Zorb desulfurization unit 500. The heating unit 510 is used to heat the feedstock oil A entering the S-Zorb desulfurization unit 500, so as to more efficiently achieve desulfurization and improve the overall working efficiency of the device.

[0114] In the present invention, the heating unit 510 can also be the same as the heating unit described in the first aspect of the present invention, and there is no particular limitation.

[0115] In the present invention, the second desulfurized product feeding unit may include various second desulfurized product conveying pipelines, power components, valves, etc. that can convey the second desulfurized product M generated by the S-Zorb desulfurization unit 500 from the S-Zorb desulfurization unit 500 to a designated position, without particular limitation.

[0116] Preferably, in order to feed the second desulfurized product M into the connecting pipeline after the olefin removal unit 400, the second desulfurized product conveying pipeline of the second desulfurized product feeding unit includes branch pipelines 110 and 120. The branch pipeline 110 can convey the partial second desulfurized product M1 from the S-Zorb desulfurization unit 500 to the membrane mixing unit 300; the branch pipeline 120 can convey the other part of the second desulfurized product M2 from the S-Zorb desulfurization unit 500 into the connecting pipeline after the olefin removal unit 400.

[0117] Furthermore, more preferably, a flow regulating valve 121 is further provided on the branch pipeline 120 for regulating the flow rate of the other part of the second desulfurized product M2 conveyed from the S-Zorb desulfurization unit 500 into the connecting pipeline after the olefin removal unit 400, thereby further controlling the weight ratio of the partial second desulfurized product M1 to the other part of the second desulfurized product M2 to obtain a high-quality gasoline fraction H'.

[0118] In addition to the above units, the gasoline preparation device according to the second aspect of the present invention may further include: a feedstock oil feeding unit 100, which is connected to the S-Zorb desulfurization unit 500 for supplying feedstock oil A to the S-Zorb desulfurization unit 500; a gas supply unit 200, which is connected to the feedstock oil feeding unit 100 and the membrane mixing unit 300 for supplying hydrogen to the feedstock oil A and the membrane mixing unit 300; a gas-liquid separation unit 700, which is connected to the olefin removal unit 400 and is disposed after the olefin removal unit 400 for separating the reaction tail gas G' and the second liquid phase F'; a fractionation unit 800, which is connected to the gas-liquid separation unit 700 and is disposed after the gas-liquid separation unit 700 for fractionating the second liquid phase F' obtained by gas-liquid separation to obtain a gasoline fraction H'.

[0119] The gas supply unit 200, the gas-liquid separation unit 700, and the fractionation unit 800 in the second aspect of the present invention may be the same as those in the first aspect of the present invention, and will not be described separately here.

[0120] In addition to this, the gasoline preparation device according to the second aspect of the present invention may further include one or more heat exchange units, various valves, and components such as pipelines for connecting the above-mentioned units to each other. The above-mentioned components are conventional structures in the art and will not be elaborated here.

[0121] In the present invention, preferably, Figure 2 The gasoline preparation device shown further includes heat exchange units 640 , 650 .

[0122] Preferably, the heat exchange unit 640 is disposed on the connecting pipeline between the crude oil feeding unit 100 and the S-Zorb desulfurization unit 500 , and is used to heat the crude oil to improve the desulfurization effect of the crude oil in the S-Zorb desulfurization unit 500 .

[0123] Preferably, the heat exchange unit 650 is arranged on the connecting pipeline between the S-Zorb desulfurization unit 500 and the membrane mixing unit 300, and is arranged before the branch pipeline 110 of the second desulfurization product feeding unit, and is used to heat the second desulfurization product M, thereby increasing the rate of subsequent hydrogenation reaction and improving the overall working efficiency of the device.

[0124] Next, combine Figure 2 , a particularly preferred embodiment of the gasoline preparation device according to the second aspect of the present invention is described. Figure 2 The gasoline preparation device shown includes a crude oil feed unit 100, a gas supply unit 200, an S-Zorb desulfurization unit 500, a second desulfurization product feed unit, a membrane mixing unit 300, a deolefination unit 400, a gas-liquid separation unit 700, a fractionation unit 800, and two heat exchange units 640 and 650. The crude oil feed unit 100 includes an oil storage tank for storing crude oil, a crude oil delivery pipeline for delivering crude oil, and a pump ( Figure 2(not shown in the figure) etc., which convey the feedstock oil A to the S-Zorb desulfurization unit 500, and a heat exchange unit 640 is provided on the connecting pipeline between the feedstock oil feeding unit 100 and the S-Zorb desulfurization unit 500. The gas supply unit 200 is connected to the feedstock oil feeding unit 100 and the membrane mixing unit 300. Specifically, the gas supply unit 200 sends a part of hydrogen B1 into the pipeline behind the storage tank of the feedstock oil feeding unit 100 through a branched gas transmission pipeline, so that a part of hydrogen B1 is mixed with the feedstock oil A; and another part of hydrogen B2 is sent into the membrane mixing unit 300 through a branched gas transmission pipeline. The second desulfurized product feeding unit includes a branched pipeline 110 for conveying a part of the second desulfurized product M1 generated by the S-Zorb desulfurization unit 500 to the membrane mixing unit 300, and a branched pipeline 120 for conveying another part of the second desulfurized product M2 generated by the S-Zorb desulfurization unit 500 to the connecting pipeline after the deolefination unit 400, and a flow regulating valve 121 is provided on the branched pipeline 120. The S-Zorb desulfurization unit 500 is connected to the membrane mixing unit 300, and a part of the desulfurized product M1 is sent into the membrane mixer through the second desulfurized product feeding unit. The membrane mixing unit 300 is sequentially connected to the deolefination unit 400, the gas-liquid separation unit 700, and the fractionation unit 800.

[0125] According to the present invention, in a preferred embodiment as shown in Figure 2 by arranging the deolefination reaction unit 400 after the S-Zorb desulfurization unit 500, olefins in the feedstock oil can be effectively removed while reducing the sulfur content, and the quality of the obtained gasoline fraction can be improved on the basis of maximizing the retention of the octane number.

[0126] According to the first and second aspects of the present invention, the feedstock oil can be one or more of catalytic cracking gasoline, coking gasoline, and pyrolysis gasoline; preferably, the feedstock oil is catalytic cracking gasoline.

[0127] In addition, the distillation range of the feedstock oil can be 35 - 210 °C, and the olefin content in the feedstock oil can be 18 - 35 vol%; preferably, the distillation range of the feedstock oil is 39 - 205 °C, and the olefin content in the feedstock oil is 18 - 27 vol%.

[0128] The third aspect of the present invention provides a method for preparing gasoline, which is carried out by using the device described in the first aspect of the present invention, and includes the following steps:

[0129] 1) A step of mixing a part of the feedstock oil A1 with hydrogen in the membrane mixing unit 300;

[0130] 2) A step of subjecting the mixed feedstock oil in step 1) to hydrogenation in the de-olefination unit 400;

[0131] 3) A step of subjecting the first hydrogenation product C obtained in step 2) and another part of the feedstock oil A2 fed from the branch pipeline 120 of the feedstock oil feeding unit to desulfurization in the S-Zorb desulfurization unit 500,

[0132] wherein, the said part of the feedstock oil (A1) accounts for more than 30% by weight of the total weight of the said part of the feedstock oil (A1) and the said another part of the feedstock oil (A2).

[0133] According to the third aspect of the present invention, the feedstock oil A can be various feedstock oils commonly used in the art for preparing gasoline. Preferably, the feedstock oil A is one or more of catalytic cracking gasoline, coking gasoline, and pyrolysis gasoline; more preferably, the feedstock oil A is catalytic cracking gasoline.

[0134] In the present invention, the distillation range of the feedstock oil A can be 35 - 210 °C, and the olefin content in the feedstock oil A is 18 - 35% by volume; preferably, the distillation range of the feedstock oil A is 39 - 205 °C, and the olefin content in the feedstock oil A is 18 - 27% by volume.

[0135] In the present invention, by controlling the weight ratio of the said part of the feedstock oil A1 to the said another part of the feedstock oil A2 within the above range, the olefin content in the prepared gasoline can be reduced on the basis of maximizing the retention of the octane number, making it meet the national VI gasoline standard.

[0136] Preferably, the said part of the feedstock oil (A1) accounts for 50 - 70% by weight of the total weight of the said part of the feedstock oil (A1) and the said another part of the feedstock oil (A2). By controlling the weight ratio of the above two parts of the feedstock oil within this range, the quality of the prepared gasoline can be further improved.

[0137] According to the third aspect of the present invention, preferably, the feedstock oil A is contacted with a part of hydrogen B1 in the feedstock oil feeding unit 100, and the volume ratio of the feedstock oil A to the said part of hydrogen B1 is 1:1 - 25, more preferably, the volume ratio of the feedstock oil A to the said part of hydrogen B1 is 1:5 - 20. Thereby, the coking of gasoline in the heat exchange unit can be slowed down, and the service life of the device can be extended.

[0138] In addition, preferably, another part of hydrogen B2 is mixed with a part of the feedstock oil A1 in the membrane mixing unit 300. In the present invention, the volume ratio of the said another part of hydrogen B2 to the said part of the feedstock oil A1 is not particularly limited, as long as it can combine with the volume ratio of the above feedstock oil A to the said part of hydrogen B1 to adjust the final hydrogen-oil volume ratio to the hydrogenation conditions in the subsequent hydrogenation unit 400.

[0139] For example, in the present invention, the volume ratio of the partial feedstock oil A1 to the other part of hydrogen B2 may be 1:1 - 60. More preferably, the volume ratio of the partial feedstock oil A1 to the other part of hydrogen B2 is 1:10 - 30. Thus, hydrogenation can be better achieved, and the quality of the obtained gasoline fraction can be improved.

[0140] In addition, before the step of mixing the partial feedstock oil A1 with hydrogen in the membrane mixing unit 300 in step 1), the partial feedstock oil A1 can be preheated in advance through the heat exchange unit 610 to facilitate subsequent hydrogenation treatment in the olefin removal unit 400. Preferably, the preheating temperature is 100 - 200 °C. More preferably, the preheating temperature is 140 - 180 °C.

[0141] Similarly, before step 3), before the other part of the feedstock oil A2 enters the S-Zorb desulfurization unit 500, it can also be preheated to facilitate subsequent desulfurization treatment in the S-Zorb desulfurization unit 500. Preferably, before the other part of the feedstock oil A2 and the partial feedstock oil A1 enter the branch pipeline, they are simultaneously heated at the heat exchange unit 620, thereby improving the working efficiency of the entire device and the energy utilization rate.

[0142] According to the present invention, after the partial feedstock oil A1 is mixed with hydrogen in the membrane mixing unit 300, the mixed feedstock oil is hydrogenated in the olefin removal unit 400 in the presence of a hydrogenation catalyst.

[0143] In addition, in the present invention, there is no particular limitation on the entry direction of the partial feedstock oil A1 from the catalyst bed during hydrogenation in the olefin removal unit 400. For example, the partial feedstock oil A1 can enter from the bottom of the catalyst bed from bottom to top for hydrogenation, or the partial feedstock oil A1 can also enter from the top of the catalyst bed from top to bottom for hydrogenation.

[0144] In the present invention, the selection of the hydrogenation catalyst is very crucial. Preferably, it is a hydrogenation catalyst that can reduce the olefin content in the feedstock oil through hydrogenation and can retain the high-octane partial feedstock to the maximum extent.

[0145] In the present invention, preferably, the hydrogenation catalyst contains a carrier and an active component supported on the carrier. As the carrier, it can contain at least one of alumina, USY, and silica; as the active component, it can contain at least two of the metal elements Mo, Ni, and Co. Preferably, the metal elements Mo and Ni are selected as the active components, so that during hydrogenation, while removing some olefins, high-octane olefins can be further retained.

[0146] Examples of the hydrogenation catalyst include: Catalyst HDD-2 (the active components are metal elements Mo and Ni) or HGO-2 (the active components are metal elements Mo and Co) of Hunan Changling Petrochemical Technology Development Co., Ltd. Among them, HDD-2 is more preferably used as the hydrogenation catalyst. By using this catalyst, on the one hand, the olefin content in the overall feedstock oil can be reduced, and on the other hand, part of the olefins with high octane number can be retained, so as to obtain high-quality gasoline fractions.

[0147] In the present invention, the conditions for hydrogenation may include: the pressure is 2.2 - 4 MPa, the temperature is 100 - 200 °C, the liquid hourly space velocity is 0.5 - 12.0 h -1 , and the hydrogen-oil volume ratio is 3 - 60:1; preferably, the conditions for hydrogenation include: the pressure is 2.5 - 3 MPa, the temperature is 140 - 180 °C, the liquid hourly space velocity is 4 - 8 h -1 , and the hydrogen-oil volume ratio is 10 - 30:1. By carrying out hydrogenation under the above conditions, the hydrogenation rate can be increased, and the removal effect of olefins in the feedstock oil and the quality of the obtained hydrogenated product can be ensured.

[0148] According to the third aspect of the present invention, after obtaining the first hydrogenated product C by hydrogenation, C is mixed with the other part of the feedstock oil A2 to obtain a mixed hydrogenated product D.

[0149] In order to improve the subsequent desulfurization efficiency and effect, in the present invention, preferably, the mixed hydrogenated product D is preheated at the heat exchange unit 620. The temperature of the preheating can vary within a large range. For example, the temperature of the preheating can be 300 - 420 °C, preferably, the temperature of the preheating is 380 - 420 °C.

[0150] Before the mixed hydrogenated product D enters the S-Zorb desulfurization unit 500 for desulfurization, in order to further improve the desulfurization efficiency, preferably, it is heated through the heating furnace 510. Preferably, the temperature of the heating is 410 - 420 °C.

[0151] In the present invention, when desulfurization is carried out in the S-Zorb desulfurization unit 500, the conditions for desulfurization can be the conventional conditions generally used for desulfurization of feedstock oil in the art, without special limitations. For example, the desulfurization conditions may include: the temperature is 410 - 435 °C, the pressure is 2.0 - 3.5 MPa, preferably, the desulfurization conditions include: the temperature is 420 - 430 °C, the pressure is 2.5 - 3.0 MPa.

[0152] According to the present invention, after desulfurization is carried out in the S-Zorb desulfurization unit 500, a first desulfurized product E is obtained. To separate the reaction tail gas G and the first liquid phase F in the first desulfurized product E, preferably, the method according to the third aspect of the present invention further includes a step of carrying out gas-liquid separation of the first desulfurized product E in the gas-liquid separation unit 700.

[0153] To improve the effect of the gas-liquid separation and enhance the treatment speed, preferably, before the first desulfurized product enters the gas-liquid separation unit 700, it is cooled through the heat exchange unit 630. Preferably, the temperature of the cooling is 130 - 200 °C; more preferably, the temperature of the cooling is 130 - 170 °C.

[0154] In the present invention, through the gas-liquid separation unit 700, the separated first liquid phase F is obtained.

[0155] To improve the quality of the prepared gasoline, the method according to the third aspect of the present invention further includes a step of fractionating the first liquid phase F in the fractionation unit 800.

[0156] In the present invention, the fractionation can be carried out by various methods and conditions commonly used in the art for separation, without particular limitation. Preferably, C3 and lower components in the first liquid phase are removed through fractionation to obtain a gasoline fraction.

[0157] Through the method according to the third aspect of the present invention, the olefin content in the prepared gasoline is 18 vol% or less, and the sulfur content is 10 ppm or less; preferably, the olefin content in the prepared gasoline is 15 vol% or less, and the sulfur content is 8 ppm or less; more preferably, the sulfur content in the prepared gasoline is 6 ppm or less.

[0158] The fourth aspect of the present invention provides a method for preparing gasoline. This method uses the preparation device according to the second aspect of the present invention and includes the following steps:

[0159] 1) A step of subjecting the feedstock oil A to desulfurization in the S-Zorb desulfurization unit 500;

[0160] 2) A step of mixing a part of the second desulfurized product M1 obtained in step 1) with hydrogen in the membrane mixing unit 300 and then carrying out hydrogenation in the de-olefination unit 400;

[0161] 3) A step of mixing the second hydrogenated product N obtained in step 2) with another part of the second desulfurized product M2 obtained in step 1), wherein the part of the second desulfurized product M1 accounts for more than 25 wt% of the total weight of the part of the second desulfurized product M1 and the other part of the second desulfurized product M2.

[0162] The feedstock A used in the method according to the fourth aspect of the present invention may be the same as that in the third aspect of the present invention, and will not be described herein again.

[0163] According to the fourth aspect of the present invention, first, all of the feedstock A is desulfurized, and then a part of the second desulfurized product M1 obtained by desulfurization is hydrogenated to obtain a second hydrogenated product N. Then, the second hydrogenated product N is mixed with another part of the second desulfurized product M2, so as to remove part of the olefins while removing sulfur from the feedstock oil and maximize the retention of the octane number.

[0164] According to the fourth aspect of the present invention, by controlling the weight ratio of the part of the second desulfurized product M1 to the other part of the second desulfurized product M2 within the above range, it can be ensured that the olefin content in the gasoline prepared meets the national VI gasoline standard.

[0165] Preferably, the part of the second desulfurized product M1 accounts for 50-60% by weight of the total weight of the part of the second desulfurized product M1 and the other part of the second desulfurized product M2. By controlling the weight ratio of the above two parts of the second desulfurized product within this range, the quality of the gasoline prepared can be further improved.

[0166] According to the fourth aspect of the present invention, before the step of desulfurizing the feedstock A in the S-Zorb desulfurization unit 500 in step 1), a part of the hydrogen B1 is mixed with the feedstock A to prevent coking of the S-Zorb desulfurization unit 500.

[0167] Preferably, the volume ratio of the feedstock A to the part of the hydrogen B1 is 1:1-30, and more preferably, the volume ratio of the feedstock A to the part of the hydrogen B1 is 1:5-10.

[0168] In addition, the feedstock A can be preheated in advance through the heat exchange unit 640 and the heating unit 510 to facilitate subsequent desulfurization treatment in the S-Zorb desulfurization unit 500. Preferably, the preheating temperature is 300-420°C, and more preferably, the preheating temperature is 410-420°C.

[0169] In the present invention, the preheating treatment is carried out by two-step heating through the heat exchange unit 640 and the heating unit 510, and there is no particular limitation on the temperature of each step of heating. For example, the feedstock oil mixed with hydrogen can be first heated to 300-400°C through the heat exchange unit 640, and then heated to 300-420°C through the heating unit 510.

[0170] In addition, in the present invention, the second desulfurized product M obtained by desulfurizing the feedstock oil A through the heat exchange unit 650 can be cooled, which is conducive to the subsequent steps. For example, the temperature of the second desulfurized product M can be reduced to 100-200°C through the heat exchanger 650. Preferably, the temperature of the second desulfurized product M is reduced to 130-170°C through the heat exchange unit 650.

[0171] Next, a part of the second desulfurized product M1 and another part of hydrogen B2 are mixed in the membrane mixing unit 300 through the second desulfurized product feeding unit. The volume ratio of the part of the second desulfurized product M1 to the other part of hydrogen B2 can be 1:1-60. More preferably, the volume ratio of the part of the second desulfurized product M1 to the other part of hydrogen B2 is 1:10-30. By mixing another part of hydrogen B2 with a part of the second desulfurized product M1 in the membrane mixing unit 300, the effect of the subsequent hydrogenation reaction can be further improved, and thus the quality of the obtained gasoline fraction can be improved.

[0172] After the part of the second desulfurized product M1 and another part of hydrogen B2 are mixed in the membrane mixing unit 300, hydrogenation is carried out in the olefin removal unit 400 to obtain the second hydrogenated product N, and the other part of the second desulfurized product M2 is mixed with the second hydrogenated product N to obtain the mixed desulfurized and hydrogenated product P.

[0173] Preferably, the method according to the fourth aspect of the present invention further includes the steps of gas-liquid separation of the mixed desulfurized and hydrogenated product P in the gas-liquid separation unit 700 to obtain the second liquid phase F', and fractionation of the second liquid phase F' in the fractionation unit 800.

[0174] The conditions of the hydrogenation, desulfurization, gas-liquid separation, fractionation and other treatments according to the fourth aspect of the present invention and the hydrogenation catalyst used can be the same as those described in the third aspect of the present invention, and will not be elaborated here.

[0175] Through the method according to the fourth aspect of the present invention, the olefin content in the prepared gasoline is 18% by volume or less, and the sulfur content is 10 ppm or less; preferably, the olefin content in the prepared gasoline is 15% by volume or less, and the sulfur content is 8 ppm or less; more preferably, the sulfur content of the prepared gasoline is 6 ppm or less.

[0176] The present invention will be described in detail below through examples.

[0177] In the following examples and comparative examples, the feedstock oil used is catalytic cracking gasoline, and its basic properties are shown in Table 1.

[0178] Table 1

[0179]

[0180] Example 1

[0181] use Figure 1 The device shown is carried out as Figure 1 As shown, the gasoline preparation device includes a crude oil feed unit 100, a gas supply unit 200, a membrane mixing unit 300, a deolefination unit 400, an S-Zorb desulfurization unit 500, a gas-liquid separation unit 700, a fractionation unit 800 and three heat exchange units 610, 620, 630.

[0182] The crude oil feed unit 100 includes an oil storage tank for storing crude oil, a crude oil delivery pipeline for delivering crude oil, and a pump ( Figure 1 ), the crude oil delivery pipeline further includes branch pipelines 110 and 120, the branch pipeline 110 is connected to the membrane mixing unit 300, and the heat exchange unit 610 is arranged on the connecting pipeline between the crude oil feed unit 100 and the membrane mixer 300; the branch pipeline 120 is connected to the connecting pipeline between the deolefination unit 400 and the S-Zorb desulfurization unit 500, and a flow regulating valve 121 is arranged on the branch pipeline 120.

[0183] The gas supply unit 200 is connected to the crude oil feed unit 100 and the membrane mixing unit 300. Specifically, the gas supply unit 200 sends part of the hydrogen B1 into the pipeline behind the oil storage tank of the crude oil feed unit 100 and before the branch pipeline of the crude oil feed unit 100 through a branch gas pipeline, so that part of the hydrogen B1 is mixed with the crude oil A; in addition, another part of the hydrogen B2 is sent into the membrane mixing unit 300 through a branch gas pipeline.

[0184] The membrane mixing unit 300 is sequentially connected to the deolefination unit 400 , the heat exchange unit 620 , the heating unit 510 , the S-Zorb desulfurization unit 500 , the heat exchange unit 630 , the gas-liquid separation unit 700 and the fractionation unit 800 through pipelines.

[0185] Among them, the membrane mixing unit 300 is a membrane mixer, which has two concentric tubular channels, one of which is a liquid channel for containing crude oil, and the other is a gas channel for containing hydrogen, and the liquid channel is inside the gas channel, the tube wall of the liquid channel (that is, the inner tube wall of the gas channel) is a membrane tube with through holes with an average pore size of nanometer size (the membrane tube was purchased from Beijing Zhongtianyuan Environmental Engineering Co., Ltd., with a pore size of 0.05μm), and the tube wall of the gas channel is a porous ceramic material.

[0186] The olefin removal unit 400 is an axial reactor, the S-Zorb desulfurization unit 500 is a fluidized bed reactor, the heating unit 510 is a heating furnace, the gas-liquid separation unit 700 is a horizontal high-pressure separator, the fractionation unit 800 is a plate fractionating column, and the heat exchange units 610, 620, and 630 are heat exchangers.

[0187] The preparation method of gasoline fraction using the above device is as follows:

[0188] 1) Mix the feedstock oil A with a part of hydrogen B1 in a volume ratio of 1:5, and then heat it to 160 °C under a pressure of 3.0 MPa through the heat exchange unit 610.

[0189] 2) After mixing the part of the feedstock oil A1 obtained in step 1) with another part of hydrogen B2 in a volume ratio of 1:25 in the membrane mixing unit 300, carry out a hydrogenation reaction with the hydrogenation catalyst in the olefin removal unit 400 from bottom to top. The conditions of the hydrogenation reaction include: a pressure of 3.0 MPa, a temperature of 160 °C, a liquid hourly space velocity of 4.0 h -1 , and a hydrogen-oil volume ratio of 30:1. Among them, the hydrogenation catalyst used is a commercial catalyst HDD-2 (produced by Hunan Changling Petrochemical Technology Development Co., Ltd.), its carrier is γ-Al2O3, and its active components are Mo and Ni.

[0190] 3) Mix the first hydrogenation product C obtained in step 2) with another part of the feedstock oil A2 to obtain a mixed hydrogenation product D. Among them, the weight ratio of the part of the feedstock oil A1 to the another part of the feedstock oil A2 is 1:1.

[0191] 4) Heat the mixed hydrogenation product D obtained in step 3) to 380 °C through the heat exchange unit 620, and then heat it to 420 °C through the heating unit 510, and then enter the S-Zorb desulfurization unit 500 for desulfurization to obtain a first desulfurized product E. Among them, the conditions of the desulfurization include: a temperature of 420 °C and a pressure of 2.7 MPa.

[0192] 5) Carry out gas-liquid separation on the first desulfurized product E obtained in step 4) through the gas-liquid separation unit 700 to obtain a first liquid phase F. Among them, the conditions of the gas-liquid separation include: a temperature of 135 - 140 °C and a pressure of 2.57 MPa.

[0193] 6) Fractionate the first liquid phase F obtained in step 5) through the fractionation unit 800, and separate the gasoline fraction H from the bottom of the tower. Among them, the conditions of the fractionation include: a pressure of 0.5 - 0.6 MPa, a feed temperature of 130 °C, and a bottom temperature of 136 °C.

[0194] The properties of the first hydrogenation product C, the mixed hydrogenation product D, the first desulfurization product E and the gasoline fraction H prepared thereby are shown in Table 2.

[0195] Example 2

[0196] The apparatus described in Example 1 was used and the method described in Example 1 was carried out, except that:

[0197] In step 2), the conditions of the hydrogenation reaction included: the pressure was 3.0 MPa, the temperature was 150 °C, the liquid hourly space velocity was 6.0 h -1 , and the hydrogen-oil volume ratio was 25:1 (adjusting the volume ratio of a part of the raw material oil A1 obtained in step 1) and another part of the hydrogen B2, the same below);

[0198] In step 3), the weight ratio of the part of the raw material oil A1 to the other part of the raw material oil A2 was 7:3.

[0199] The properties of the first hydrogenation product C, the mixed hydrogenation product D, the first desulfurization product E and the gasoline fraction H prepared thereby are shown in Table 2.

[0200] Example 3

[0201] The apparatus described in Example 1 was used and the method described in Example 1 was carried out, except that:

[0202] In step 2), the conditions of the hydrogenation reaction included: the pressure was 3.0 MPa, the temperature was 180 °C, the liquid hourly space velocity was 4.0 h -1 , and the hydrogen-oil volume ratio was 30:1;

[0203] In step 3), the weight ratio of the part of the raw material oil A1 to the other part of the raw material oil A2 was 3:7.

[0204] The properties of the first hydrogenation product C, the mixed hydrogenation product D, the first desulfurization product E and the gasoline fraction H prepared thereby are shown in Table 2.

[0205] Example 4

[0206] The apparatus described in Example 1 was used and the method described in Example 1 was carried out, except that:

[0207] In step 2), the hydrogenation catalyst HDD-2 was replaced with the hydrogenation catalyst HGO-2, the carrier of which was γ-Al2O3 and the active components were Mo and Co.

[0208] The properties of the first hydrogenation product C, the mixed hydrogenation product D, the first desulfurization product E and the gasoline fraction H prepared thereby are shown in Table 2 (continued).

[0209] Comparative Example 1

[0210] The device described in Example 1 is adopted and the method described in Example 1 is followed, with the difference that:

[0211] In step 3), the weight ratio of the part of the feedstock oil A1 to the other part of the feedstock oil A2 is 1:3.

[0212] The properties of the first hydrogenation product C, the mixed hydrogenation product D, the first desulfurization product E and the gasoline fraction H prepared thereby are shown in Table 2 (continued) as follows.

[0213] Table 2

[0214]

[0215] Table 2 (continued)

[0216]

[0217] It can be seen from the results of Table 2 and Table 2 (continued) that by adopting the methods of Examples 1-4 of the present invention, by hydrogenating a part of the feedstock oil and then mixing and desulfurizing it with the other part of the feedstock oil, the olefin content in the gasoline fraction can be effectively reduced (reduced to below 15 v%), the octane number can be preferably retained, and coking of the heat exchange unit and the S-Zorb desulfurization unit can be prevented, and the operation cycle of the device can be extended.

[0218] Example 5

[0219] Adopt as Figure 2 shown, and as Figure 2 shown, this gasoline preparation device includes a feedstock oil feeding unit 100, a gas supply unit 200, an S-Zorb desulfurization unit 500, a second desulfurization product feeding unit, a membrane mixing unit 300, a deolefination unit 400, a gas-liquid separation unit 700, a fractionation unit 800 and two heat exchange units 640, 650.

[0220] Among them, the feedstock oil feeding unit 100 includes an oil storage tank for storing the feedstock oil, a feedstock oil conveying pipeline for conveying the feedstock oil and a pump for providing power ( Figure 2 not shown in the figure), which conveys the feedstock oil A to the S-Zorb desulfurization unit 500, and a heat exchange unit 640 is arranged on the connecting pipeline between the feedstock oil feeding unit 100 and the S-Zorb desulfurization unit 500.

[0221] The gas supply unit 200 is connected to the feedstock oil feeding unit 100 and the membrane mixing unit 300. Specifically, the gas supply unit 200 sends a part of hydrogen B1 into the pipeline behind the storage tank of the feedstock oil feeding unit 100 through a branched gas pipeline, so that a part of hydrogen B1 is mixed with the feedstock oil A; and another part of hydrogen B2 is sent into the membrane mixing unit 300 through a branched gas pipeline.

[0222] The second desulfurized product feeding unit includes a branched pipeline 110 for transporting a part of the second desulfurized product M1 generated by the S-Zorb desulfurization unit 500 to the membrane mixing unit 300, and a branched pipeline 120 for transporting another part of the second desulfurized product M2 generated by the S-Zorb desulfurization unit 500 to the connecting pipeline after the olefin removal unit 400, and a flow regulating valve 121 is provided on the branched pipeline 120.

[0223] The S-Zorb desulfurization unit 500 is connected to the membrane mixing unit 300, and a part of the second desulfurized product M1 is sent into the membrane mixer through the second desulfurized product feeding unit. The membrane mixing unit 300 is sequentially connected with the olefin removal unit 400, the gas-liquid separation unit 700, and the fractionation unit 800.

[0224] Among them, the membrane mixing unit 300, the olefin removal unit 400, the S-Zorb desulfurization unit 500, the heating unit 510, the gas-liquid separation unit 700, the fractionation unit 800, and the heat exchange units 640 and 650 are the same as those in Embodiment 1.

[0225] The preparation method of gasoline fraction using the above device is as follows:

[0226] 1) Mix the feedstock oil A with a part of hydrogen B1 in a volume ratio of 1:5, and then heat it to 400 °C under a pressure of 3.0 MPa through the heat exchange unit 640;

[0227] 2) Heat the feedstock oil A mixed with hydrogen obtained in step 1) to 420 °C through the heating unit 510, and then enter the S-Zorb desulfurization unit 500 for desulfurization. The conditions for desulfurization include: temperature of 420 °C, pressure of 3 MPa, and the second desulfurized product M is obtained;

[0228] 3) After cooling the second desulfurized product M to 160 °C through the heat exchange unit 650, mix a part of the second desulfurized product M1 with another part of hydrogen B2 in a volume ratio of 1:25 in the membrane mixer 300, and then carry out a hydrogenation reaction with the hydrogenation catalyst in the olefin removal unit 400 from bottom to top to obtain the second hydrogenation product N. Among them, the conditions for the hydrogenation reaction include: pressure of 2.8 MPa, temperature of 160 °C, and liquid hourly space velocity of 4.0 h-1 , the hydrogen-oil volume ratio is 30:1, and the hydrogenation catalyst is the same as that in Example 1;

[0229] 4) Mix the second hydrogenation product N obtained in step 3) with another part of the second desulfurized product M2 to obtain a mixed desulfurized and hydrogenated product P, wherein the weight ratio of the part of the second desulfurized product M1 to the other part of the second desulfurized product M2 is 1:1;

[0230] 5) Subject the mixed desulfurized and hydrogenated product P obtained in step 4) to gas-liquid separation through a gas-liquid separation unit 700 to obtain a second liquid phase F', wherein the conditions for the gas-liquid separation include: a temperature of 135 - 140 °C and a pressure of 2.57 MPa;

[0231] 6) Fractionate the second liquid phase F' obtained in step 5) through a fractionation unit 800, and separate a gasoline fraction H' from the bottom of the tower, wherein the conditions for the fractionation include: a pressure of 0.5 - 0.6 MPa, a feed temperature of 130 °C, and a bottom temperature of 136 °C.

[0232] The properties of the second desulfurized product M, the second hydrogenation product N, the mixed desulfurized and hydrogenated product P, and the gasoline fraction H' prepared thereby are shown in Table 3.

[0233] Example 6

[0234] Use the device described in Example 5 and carry out the method according to Example 5, except that:

[0235] In step 3), the conditions for the hydrogenation reaction include: a pressure of 2.8 MPa, a temperature of 150 °C, and a liquid hourly space velocity of 6.0 h -1 , the hydrogen-oil volume ratio is 25:1 (adjust the volume ratio of a part of the second desulfurized product M1 to another part of hydrogen B2, the same below);

[0236] In step 4), the weight ratio of the part of the second desulfurized product M1 to the other part of the second desulfurized product M2 is 6:4.

[0237] The properties of the second desulfurized product M, the second hydrogenation product N, the mixed desulfurized and hydrogenated product P, and the gasoline fraction H' prepared thereby are shown in Table 3.

[0238] Example 7

[0239] Use the device described in Example 5 and carry out the method according to Example 5, except that:

[0240] In step 3), the conditions for the hydrogenation reaction include: a pressure of 2.8 MPa, a temperature of 180 °C, and a liquid hourly space velocity of 4.0 h -1 , the hydrogen-oil volume ratio is 30:1;

[0241] In step 4), the weight ratio of a part of the second desulfurized product M1 to the other part of the second desulfurized product M2 is 1:3.

[0242] The properties of the second desulfurized product M, the second hydrogenated product N, the mixed desulfurized and hydrogenated product P, and the gasoline fraction H' prepared thereby are shown in Table 3.

[0243] Example 8

[0244] The apparatus described in Example 5 was used and the method described in Example 5 was followed, except that:

[0245] In step 3), the catalyst in Example 4 was used;

[0246] The properties of the second desulfurized product M, the second hydrogenated product N, the mixed desulfurized and hydrogenated product P, and the gasoline fraction H' prepared thereby are shown in Table 3 (continued).

[0247] Comparative Example 2

[0248] The apparatus described in Example 5 was used and the method described in Example 5 was followed, except that:

[0249] In step 4), the weight ratio of a part of the second desulfurized product M1 to the other part of the second desulfurized product M2 is 1:4.

[0250] The properties of the second desulfurized product M, the second hydrogenated product N, the mixed desulfurized and hydrogenated product P, and the gasoline fraction H' prepared thereby are shown in Table 3 (continued).

[0251] Table 3

[0252]

[0253]

[0254] Table 3 (continued)

[0255]

[0256] As can be seen from Table 3 and Table 3 (continued), within the weight ratio range of a part of the second desulfurized product to the other part of the second desulfurized product defined in the present invention, by hydrogenating a part of the second desulfurized product after desulfurization and then mixing it with the other part of the second desulfurized product, the olefin content in the gasoline fraction can be effectively reduced and the octane number can be retained to a large extent.

[0257] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any other suitable combination of each technical feature. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.

Claims

1. A device for preparing gasoline, characterized in that, The device includes an S-Zorb desulfurization unit (500), a membrane mixing unit (300), and an olefin removal unit (400) connected in sequence. Among them, a second desulfurized product feeding unit is connected to the connecting pipeline after the olefin removal unit (400) for feeding the second desulfurized product into the connecting pipeline.

2. The preparation device according to claim 1, wherein, The second desulfurized product feeding unit includes a second desulfurized product conveying pipeline.

3. The preparation device according to claim 1, wherein, The second desulfurized product feeding unit includes branch pipelines (110, 120) respectively used for feeding the second desulfurized product into the membrane mixing unit (300) and the connecting pipeline.

4. The preparation device according to claim 3, wherein, A flow regulating valve (121) is provided on the branch pipeline (120).

5. The preparation device according to claim 1, wherein The device further includes: A feedstock oil feeding unit (100) connected to the S-Zorb desulfurization unit (500); A gas supply unit (200) connected to the feedstock oil feeding unit (100) and the membrane mixing unit (300); A gas-liquid separation unit (700) provided after the olefin removal unit (400); and A fractionation unit (800) provided after the gas-liquid separation unit (700).

6. The preparation device according to claim 5, wherein, The S-Zorb desulfurization unit (500) further includes a heating unit (510).

7. The preparation device according to claim 6, wherein, The heating unit (510) is provided between the feedstock oil feeding unit (100) and the body of the S-Zorb desulfurization unit (500).

8. The production device according to any one of claims 1-7, wherein, The membrane mixing unit (300) includes at least one liquid channel for accommodating feedstock oil or the second desulfurized product and a gas channel for accommodating hydrogen. The liquid channel and the gas channel are adjacent through a membrane tube with through holes having an average pore size in the nanometer scale.

9. The production device according to claim 8, wherein, The membrane tube is formed of a porous material.

10. A method for preparing gasoline, characterized in that, This method uses the preparation device according to any one of claims 1-9 and includes the following steps: 1) A step of desulfurizing the feedstock oil (A) in the S-Zorb desulfurization unit (500); 2) A step of mixing a part of the second desulfurized product (M1) obtained in step 1) with hydrogen in the membrane mixing unit (300) and then performing hydrogenation in the olefin removal unit (400); 3) A step of mixing the second hydrogenated product (N) obtained in step 2) with another part of the second desulfurized product (M2) obtained in step 1), wherein the part of the second desulfurized product (M1) accounts for more than 25% by weight of the total weight of the part of the second desulfurized product (M1) and the other part of the second desulfurized product (M2).

11. According to the preparation method described in claim 10, wherein, The part of the second desulfurized product (M1) accounts for 50-60% by weight of the total weight of the part of the second desulfurized product (M1) and the other part of the second desulfurized product (M2).

12. The preparation method according to claim 10, wherein, The step of hydrogenation is carried out in the presence of a hydrogenation catalyst, the hydrogenation catalyst contains a carrier and an active component supported on the carrier, and the carrier contains at least one of alumina, USY, and silica, and the active component contains at least two of the metal elements Mo, Ni, and Co; The hydrogenation conditions include: a pressure of 2.2 - 4 MPa, a temperature of 100 - 200 °C, a liquid hourly space velocity of 0.5 - 12.0 h -1 , and a hydrogen-to-oil volume ratio of 3 - 60:

1.

13. The preparation method according to claim 10, wherein The feedstock oil is one or more of catalytic cracking gasoline, coking gasoline, and pyrolysis gasoline; The distillation range of the feedstock oil is 35 - 210 °C, and the olefin content in the feedstock oil is 18 - 35 vol%.

14. The preparation method according to claim 13, wherein, The feedstock oil is catalytic cracking gasoline; The distillation range of the feedstock oil is 39 - 205 °C, and the olefin content in the feedstock oil is 18 - 27 vol%.

15. The preparation method according to any one of claims 10-14, wherein, The olefin content in the produced gasoline is 18 vol% or less, and the sulfur content is 10 ppm or less.

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