A process and system for producing high value-added products from crude oil

Abstract

The present application relates to a kind of crude oil production high value-added product process, system, method includes: (1) make crude oil distillation cutting, obtain light oil, middle oil and heavy oil;(2) make light oil first separation, obtain first saturated component and first unsaturated component;(3) make middle oil second separation, obtain second saturated component and second unsaturated component;(4) make heavy oil third separation, obtain third saturated component and third unsaturated component;(5) make catalytic cracking raw material and catalyst contact and carry out catalytic cracking reaction, through oil gas separation and obtain cracking gas, cracking light gasoline, cracking heavy gasoline, cracking diesel and cracking heavy oil;Catalytic cracking raw material includes first saturated component, second saturated component, third saturated component and optional difficult conversion component, difficult conversion component includes light hydrocarbon and / or light distillate oil.The crude oil of the present application is strong, the utilization rate of crude oil is high, the yield of high value-added product is high and the device on-line rate is high.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of petroleum chemical industry, and particularly relates to a process method and system for producing high value-added products from crude oil. BACKGROUND

[0002] The refining capacity is excessive, the demand for refined oil is gradually slow, and ethylene, propylene and BTX (benzene-toluene-xylene) are key basic organic synthesis raw materials with huge demand. The demand for chemical products is continuously strong. The existing technical route for producing propylene and BTX from petroleum is developed on the basis of the traditional petroleum refining process mainly for producing oil products, and there are problems such as long production process, low chemical yield and insignificant economic benefit. The technical measures to solve the problem are to develop the key core technology of producing chemicals mainly, and the crude oil hydrocarbon molecules can be directionally converted into chemicals. Therefore, in recent years, international petrochemical companies represented by ExxonMobil Company and Saudi Aramco have begun to innovate the traditional refining process. These companies have overturned the traditional refining process and upgraded the refining and chemical integration to a new level of direct production of chemicals from crude oil.

[0003] ExxonMobil Company is the pioneer of research and development of producing olefins from crude oil steam cracking, and is the first company to build an industrial demonstration device, and has applied a series of patents, such as CN 200580016314.X. The process method of direct chemical production of the company is that the crude oil directly enters the steam cracking furnace, the light components and heavy components are separated by flashing, the light components (gaseous components) enter the steam cracking furnace for cracking, and the heavy components (liquid components) are used as refinery feedstock. If the selected crude oil is light enough, there is no 593℃ or more distillate, that is, no tower bottom residue, and it can not rely on the refinery. The first industrial device of the company is to use API degree 42.7 super light paraffin-based Tapis crude oil as raw material.

[0004] The technical feature of Saudi Aramco is to adopt the crude oil pretreatment technology and hydrogenation treatment technology to reduce the influence of non-volatile components in the crude oil on steam cracking to the greatest extent. At the same time, a vapor-liquid (steam and liquid) separation device is arranged between the convection section and the radiation section of the steam cracking furnace to remove non-volatile liquids (liquid phase substances), so as to ensure that the material entering the radiation section is not entrained with liquid, thereby ensuring that the furnace tube is not coked, and the heavy components enter the catalytic cracking device. It can be said that it is a process for producing olefins and aromatic hydrocarbons from crude oil by integrating hydrogenation treatment, steam cracking and catalytic cracking process.

[0005] Due to the presence of heavy components difficult to be gasified in crude oil, the existing direct crude oil chemical production technology is only suitable for low-sulfur paraffin-based crude oil with API degree of about 45. Other crude oil chemical production technologies have different technical routes according to different heavy component treatment processes, but all adopt fraction cutting, and combine process technologies according to the properties of different distillation range fraction oils to realize crude oil production of chemicals. Compared with the traditional oil refining process, only the distillation range and quantity of cut fraction oil are changed, and the existing processing technology is integrated, but no fundamental technical change is realized. Moreover, the existing combination technology is more suitable for light crude oil or paraffin oil-based crude oil, and when inferior crude oil such as heavy crude oil or intermediate-based crude oil is used as raw material, the yield of high-value products such as chemicals is low.

[0006] How to efficiently convert crude oil into low-carbon olefins and light aromatic hydrocarbons and other high-value products to maximize the utilization of crude oil resources from the molecular level is a technical problem to be solved at present. SUMMARY

[0007] The present application provides a process method and system for producing high-value products from crude oil, which aims to better convert crude oil into low-carbon olefins and light aromatic hydrocarbons and other high-value products, improve the yield of high-value products, and maximize the utilization of crude oil resources from the molecular level.

[0008] In a first aspect, the present application relates to a process method for producing high-value products from crude oil, which comprises the following steps:

[0009] (1) subjecting crude oil to distillation cutting to obtain light oil, intermediate oil and heavy oil; wherein the cutting point of the light oil and the intermediate oil is 160-220℃, and the cutting point of the intermediate oil and the heavy oil is 260-320℃;

[0010] (2) subjecting the light oil to first separation to obtain first saturated fraction and first unsaturated fraction;

[0011] (3) subjecting the intermediate oil to second separation to obtain second saturated fraction and second unsaturated fraction;

[0012] (4) subjecting the heavy oil to third separation to obtain third saturated fraction and third unsaturated fraction;

[0013] (5) contacting a catalytic cracking raw material with a catalyst to perform a catalytic cracking reaction, and separating oil and gas to obtain cracking gas, cracking light gasoline, cracking heavy gasoline, cracking diesel and cracking heavy oil;

[0014] wherein the catalytic cracking raw material comprises the first saturated fraction, the second saturated fraction, the third saturated fraction and optional difficult-to-convert components, and the difficult-to-convert components include light hydrocarbons and / or light fraction oil.

[0015] In a second aspect, the present invention relates to a system for producing high value-added products from crude oil, the system comprising a distillation unit, a first separation unit, a second separation unit, a third separation unit, and a catalytic cracking reaction unit;

[0016] The distillation unit is equipped with a crude oil inlet, a light distillate oil outlet, a middle distillate oil outlet, and a heavy distillate oil outlet.

[0017] The light distillate oil outlet of the distillation unit is connected to the material inlet of the first separation unit. The first separation unit is also provided with a first saturated outlet and a first unsaturated outlet.

[0018] The middle distillate oil outlet of the distillation unit is connected to the material inlet of the second separation unit. The second separation unit is also provided with a second saturated outlet and a second unsaturated outlet.

[0019] The heavy distillate oil outlet of the distillation unit is connected to the material inlet of the third separation unit. The third separation unit is also provided with a third saturated outlet and a third unsaturated outlet.

[0020] The first saturated outlet, the second saturated outlet, and the third saturated outlet are respectively connected to the catalytic cracking feedstock inlet of the catalytic cracking reaction unit; the catalytic cracking reaction unit is also provided with a cracked gas outlet, a cracked light gasoline outlet, a cracked heavy gasoline outlet, a cracked diesel outlet, and a cracked heavy oil outlet.

[0021] Beneficial effects:

[0022] 1) It has strong adaptability to crude oil. By adopting a process method that combines crude oil component separation and catalytic cracking units, intermediate base crude oil or lower quality naphthenic crude oil can be converted into high value-added products.

[0023] 2) High crude oil utilization rate: Due to the large differences in the size and structure of aromatics in the distillate oil of different distillation ranges of inferior crude oil, separating the components with different hydrocarbon compositions and carrying out targeted and selective catalytic conversion according to the characteristics of the components can improve the selectivity of the process and achieve efficient utilization of crude oil.

[0024] 3) High yield of high value-added products: Unsaturated fractions rich in aromatics in light distillate oil and middle distillate oil can be directly used as aromatic components or high-octane gasoline blending components. Heavy distillate oil rich in polycyclic aromatics or asphaltenes can be used as needle coke or road asphalt feedstock depending on their properties. Saturated fractions are used as catalytic cracking feedstock to be converted into low-carbon olefins and aromatics. The yield of high value-added products in the whole process reaches 70%.

[0025] 4) The unit has a high online rate. Inferior crude oil has a high content of residual carbon, high metals and high asphaltene. After component separation, the quality of catalytic cracking feedstock is greatly improved. Not only is the yield of target products high, but the operating cycle is also extended and the online rate is improved, thereby effectively improving economic benefits.

[0026] The process or system for producing high-value-added products from crude oil according to this application can efficiently produce low-carbon olefins and light aromatics from inferior crude oil. This not only produces high-value chemical raw materials and promotes the deep integration of the refining and petrochemical industries, but also effectively addresses the challenges brought about by the scarcity of petroleum resources. Furthermore, it not only has good crude oil adaptability and high chemical yield, but also produces other high-value-added chemical raw materials as byproducts, resulting in high crude oil utilization. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of a system for producing high value-added products from crude oil, as described in this application.

[0028] Explanation of reference numerals in the attached figures

[0029] Detailed Implementation

[0030] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. Through these descriptions, the features and advantages of the present application will become clearer and more apparent.

[0031] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments. Although various aspects of embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated otherwise.

[0032] Furthermore, the technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.

[0033] Any specific numerical values ​​disclosed herein (including the endpoints of numerical ranges) are not limited to their exact values, but should be understood to also include values ​​close to the exact value, such as all possible values ​​within ±5% of the exact value. Furthermore, with respect to the disclosed numerical ranges, one or more new numerical ranges can be obtained by arbitrarily combining the endpoint values ​​of the range, the endpoint values ​​with specific point values ​​within the range, and the specific point values ​​themselves; these new numerical ranges should also be considered as specifically disclosed herein.

[0034] Unless otherwise stated, the terms used herein have the same meaning as commonly understood by those skilled in the art, and if a term is defined herein and its definition differs from the common understanding in the art, the definition herein shall prevail.

[0035] In a first aspect, the present invention relates to a process for producing high value-added products from crude oil, the process comprising the following steps:

[0036] (1) Distilling crude oil to obtain light oil, intermediate oil and heavy oil; wherein the cutting point of the light oil and the intermediate oil is 160-220℃, and the cutting point of the intermediate oil and the heavy oil is 260-320℃.

[0037] (2) The light oil is subjected to a first separation to obtain a first saturated fraction and a first unsaturated fraction;

[0038] (3) The intermediate oil is subjected to a second separation to obtain a second saturated fraction and a second unsaturated fraction;

[0039] (4) The heavy oil is subjected to a third separation to obtain a third saturated fraction and a third unsaturated fraction;

[0040] (5) The catalytic cracking feedstock is brought into contact with the catalyst to carry out the catalytic cracking reaction, and the cracked gas, cracked light gasoline, cracked heavy gasoline, cracked diesel and cracked heavy oil are obtained by oil-gas separation;

[0041] The catalytic cracking feedstock comprises the first saturated fraction, the second saturated fraction, the third saturated fraction, and an optional difficult-to-convert component, wherein the difficult-to-convert component includes light hydrocarbons and / or light distillate oil.

[0042] It should be noted that light oil, middle oil, and heavy oil are abbreviations for light distillate oil, middle distillate oil, and heavy distillate oil, respectively. Optional difficult-to-convert components indicate that the catalytic cracking feedstock may not contain difficult-to-convert components, or may contain difficult-to-convert components in any proportion. The light hydrocarbons and / or light distillate oils of the difficult-to-convert components may be obtained from the process method of this application or introduced from external sources.

[0043] It should be noted that in the process method of this application, in step (1), crude oil is cut and separated into light, medium and heavy distillate oils according to different distillation ranges. As a preferred embodiment, the oil is cut according to the above-mentioned cutting points to obtain light oil, medium oil and heavy oil. In steps (2)-(4), the distillate oils of different distillation ranges are separated into components to obtain saturated and unsaturated fractions respectively. The obtained saturated fraction is rich in saturated hydrocarbons and the obtained unsaturated fraction is rich in aromatics. In step (5), the saturated fraction rich in alkanes and cycloalkanes obtained from steps (2)-(4) is used as a catalytic cracking feedstock. Under high temperature and the action of a catalyst, a catalytic cracking reaction occurs. The reaction products can be separated to obtain high-value products such as low-carbon olefins and light aromatics.

[0044] The process described in this application first involves distilling crude oil according to the aforementioned cutting points. Then, the resulting distillate fractions with different boiling ranges are separated into saturated and unsaturated fractions. These three saturated fractions are then used as feedstock for catalytic cracking. This process allows for better conversion of crude oil into high-value products such as low-carbon olefins and light aromatics, significantly increasing the yield of high-value-added products. In this application, the high-value-added product yield refers to the total yield of low-carbon olefins (ethylene, propylene, butene), light aromatics (BTX, benzene, toluene, and xylene), the first unsaturated fraction, the second unsaturated fraction, and the third unsaturated fraction.

[0045] It should be noted that in step (1), the cut-off points between light oil and intermediate oil can be 170℃, 180℃, 190℃, 200℃, 210℃, 215℃, etc., and the cut-off points between intermediate oil and heavy oil can be 265℃, 270℃, 280℃, 290℃, 300℃, 310℃, 315℃, etc. In step (5), after the catalytic cracking reaction, the cracked gas, cracked light gasoline, cracked heavy gasoline, cracked diesel, and cracked heavy oil are obtained through oil-gas separation and other steps. The separation processes involved can adopt conventional separation methods in the art or methods well known to those skilled in the art.

[0046] According to a specific embodiment of the process method described in the first aspect of the present invention, the crude oil in step (1) is selected from one or more of the following: intermediate-based crude oil, intermediate-cycloalkyl crude oil, and cycloalkyl-intermediate crude oil.

[0047] It should be noted that either the first or second key component of the intermediate-based crude oil is of intermediate-based nature; the first key component of the intermediate-based-cycloalkyl crude oil is of intermediate-based nature and the second key component is of cycloalkyl nature; the first key component of the cycloalkyl-intermediate-based crude oil is of cycloalkyl nature and the second key component is of intermediate-based nature. The process method of this application can distill and separate these inferior oils, allowing the saturated fraction to undergo catalytic cracking, thereby producing high-value products such as low-carbon olefins and light aromatics in high yields.

[0048] It should be noted that the inventors of this application have developed the process method for producing high value-added products from crude oil through years of research and development. This process method has strong raw material adaptability, is especially suitable for low-quality crude oil, and has a high yield of high value-added products, which can realize the efficient utilization of low-quality crude oil resources. Therefore, the process method of this application can be called a method for producing high value-added products from low-quality crude oil.

[0049] According to another specific embodiment of the process method described in the first aspect of the present invention, the first separation in step (2) includes: contacting the light oil with a first solvent to perform a first extraction separation;

[0050] The first solvent is selected from one or more combinations of sulfolane, methyl sulfolane, dimethyl sulfolane, and polyethylene glycol ether solvents;

[0051] The conditions for the first extraction and separation include: a temperature of 60-180℃, a pressure of 0.3-1.2 MPa, and a weight ratio of the first solvent to the light oil of (1-6):1.

[0052] It should be noted that, in one embodiment, based on the weight of the first saturated fraction, the content of saturated hydrocarbons in the first saturated fraction obtained after the first separation is 85-98% by weight. Using the aforementioned first solvent and performing the first extraction separation under the aforementioned conditions, the obtained first saturated fraction, together with the second and third saturated fractions, is used as a catalytic cracking feedstock for the catalytic cracking reaction, which is beneficial for obtaining higher value-added products.

[0053] According to a specific embodiment of the process method described in the first aspect of the present invention, the second separation in step (3) includes: contacting the intermediate oil with an ionic liquid or a second solvent to perform a second extraction separation;

[0054] The thermal stability of the ionic liquid is higher than 250℃;

[0055] The ionic liquid comprises cations and anions; the cations are selected from alkyl-substituted imidazoles and / or pyridines; the anions are selected from at least one of hexafluorophosphate, tetrafluoroborate, and bis(trifluoromethanesulfonyl)imide.

[0056] The second solvent is selected from one or more combinations of furfural, dimethyl sulfoxide, N,N-dimethylformamide, N,N-diethylformamide and morpholine;

[0057] The conditions for the second extraction and separation include: a temperature of 15-120°C, a pressure of 0.1-0.5 MPa, and the weight ratio of the ionic liquid to the intermediate oil, or the weight ratio of the second solvent to the intermediate oil, being independently (1-15):1.

[0058] It should be noted that, in one embodiment, based on the weight of the second saturated fraction, the content of saturated hydrocarbons in the second saturated fraction obtained after the second separation is 75-90% by weight. Using the aforementioned second solvent or ionic liquid, and performing the second extraction separation under the aforementioned conditions, the resulting second saturated fraction, together with the first and third saturated fractions, is used as a catalytic cracking feedstock for the catalytic cracking reaction, which is beneficial for further improving the yield of high-value-added products from the catalytic cracking.

[0059] According to a specific embodiment of the process method described in the first aspect of the present invention, the third separation in step (4) includes: contacting the heavy oil with a third solvent to perform supercritical extraction separation;

[0060] The third solvent is selected from low-carbon alkanes; the low-carbon alkanes are selected from one or a mixture of several of ethane, propane, propylene, n-butane, isobutane, n-pentane, isopentane, hexane, heptane, and octane.

[0061] The conditions for supercritical extraction separation include: a temperature of 50-100℃, a pressure of 6-20 MPa, and a weight ratio of the third solvent to the heavy oil of (2-5):1.

[0062] It should be noted that, in one embodiment, based on the weight of the third saturated fraction, the content of saturated hydrocarbons in the third saturated fraction obtained after the third separation is greater than 45% by weight. Using the third solvent mentioned above, and performing supercritical extraction separation under the above conditions, the obtained third saturated fraction, together with the first and second saturated fractions obtained in steps (2) and (3), is used as a catalytic cracking feedstock for the catalytic cracking reaction in step (5), which can better convert and generate high-value-added products.

[0063] According to a specific embodiment of the process method described in the first aspect of the present invention, the process method further includes the following steps:

[0064] This allows the first unsaturated fraction from step (2) to be used as a raw material for the production of aromatics; and / or,

[0065] This allows the second unsaturated fraction from step (3) to be used as a feedstock for the production of high-octane gasoline and / or aromatics; and / or,

[0066] This allows the third unsaturated fraction from step (4) to be used as a raw material for the production of needle coke and / or road asphalt; and / or,

[0067] This allows the pyrolysis gas from step (5) to be separated to obtain ethylene, propylene, butene and the remaining components.

[0068] It should be noted that the method for separating the cracked gas obtained from step (5) to obtain the target products such as ethylene and propylene and butene can be a conventional separation method in the art or a method well known to those skilled in the art. In the process method of this application, the saturated fraction obtained by separation in steps (2)-(4) can be used to produce high-value-added products with high yield through the catalytic cracking reaction in step (5); the unsaturated fractions rich in aromatics from different distillation ranges obtained from steps (2)-(4) can be used as raw materials for producing aromatics or high-octane gasoline, needle coke or asphalt according to their composition characteristics. In this way, both the saturated and unsaturated fractions in crude oil can be well converted or utilized, and the crude oil utilization rate is high.

[0069] According to another preferred embodiment of the process method described in the first aspect of the present invention, the light hydrocarbon of the difficult-to-convert component includes gaseous hydrocarbon products rich in C4 fractions, preferably including butene obtained by separating the cracked gas;

[0070] The light distillate oil of the difficult-to-convert component includes self-produced light distillate oil with a final boiling point of less than 280-360°C and optionally one or more of the following fractions: straight-run naphtha, straight-run kerosene, and straight-run diesel produced by other primary processing units; topping oil, residue oil, hydrocracked light naphtha, pentane oil, coking gasoline, Fischer-Tropsch synthetic oil, catalytic cracked light gasoline, hydrotreated gasoline, and hydrotreated diesel produced by other secondary processing units; and / or, the light distillate oil of the difficult-to-convert component preferably includes the cracked light gasoline obtained from step (5); the weight percentage of butene as the difficult-to-convert component in the catalytic cracking feedstock is 5-20%; the weight percentage of cracked light gasoline as the difficult-to-convert component in the catalytic cracking feedstock is 5-20%.

[0071] It should be noted that, in this preferred embodiment, the catalytic cracking feedstock in step (5) includes not only the first saturated component, the second saturated component, and the third saturated component, but also a difficult-to-convert component. The difficult-to-convert component may include butene obtained by separating cracked gas and / or the cracked light gasoline obtained by oil-gas separation. In the catalytic cracking feedstock, the weight percentage of the difficult-to-convert component may be 8%, 10%, and 15%, etc. Through years of research and development experiments, the inventors of this application have found that using the difficult-to-convert component together with the above three saturated components as catalytic cracking feedstock for the catalytic cracking reaction in step (5) is beneficial to better convert the catalytic cracking feedstock into high-value products such as low-carbon olefins (ethylene, propylene, butene) and light aromatics BTX (benzene, toluene, and xylene), which can further improve the yield of high-value-added products.

[0072] It should be noted that the light hydrocarbons of the difficult-to-convert components may include gaseous hydrocarbon products rich in C4 fractions produced by the process method of this application and gaseous hydrocarbons rich in C4 fractions produced by other process units, preferably the C4 fraction or butene produced by the process method of this application. The light distillate oils of the difficult-to-convert components may include light distillate oils with a final boiling point of less than 280-360℃ produced by the process method of this application, or one or more mixed oils such as straight-run naphtha and straight-run kerosene introduced from other external processes or units.

[0073] It should be noted that, in one embodiment, the light hydrocarbons in the difficult-to-convert component are C4 components. These C4 components refer to low-molecular-weight hydrocarbons existing in gaseous form at room temperature and pressure, with C4 fractions as the main component. They include alkanes, alkenes, and alkynes with four carbon atoms in their molecules. This includes gaseous hydrocarbon products rich in C4 fractions produced by the process of this invention, and may also include gaseous hydrocarbons rich in C4 fractions produced by other processes, with the C4 fraction produced by the process of this invention being preferred. The C4 hydrocarbons are preferably C4 fractions rich in olefins, wherein the content of C4 olefins is greater than 50% by weight, preferably greater than 60% by weight, and most preferably greater than 70% by weight.

[0074] It should be noted that, in one embodiment, the light distillate oil in the difficult-to-convert component is a light distillate oil with a final boiling point of less than 280-350℃, including light distillate oil with a final boiling point of less than 280-350℃ produced by the process method of the present invention, and may also include one or more mixtures of primary processed straight-run naphtha, straight-run kerosene, and straight-run diesel; and one or more mixtures of secondary processed topping oil, residue oil, hydrocracked light naphtha, pentane oil, coking gasoline, Fischer-Tropsch synthetic oil, catalytic cracked light gasoline, hydrotreated gasoline, and hydrotreated diesel.

[0075] According to a specific embodiment of the process method described in the first aspect of the present invention, the process method further includes the following steps:

[0076] This causes the second unsaturated fraction from step (3) to undergo a hydrogenation reaction, yielding a hydrogenated fraction;

[0077] The catalytic cracking feedstock in step (5) also includes the hydrogenation component;

[0078] The hydrogenation component accounts for 0.1-10% by weight in the catalytic cracking feedstock.

[0079] It should be noted that, as a preferred embodiment, the second unsaturated fraction from step (3) undergoes a hydrogenation reaction under the action of hydrogen and a hydrogenation catalyst to obtain a hydrogenated component, i.e., the hydrogenated second unsaturated fraction. The hydrogenated component can be used together with the first saturated fraction, the second saturated fraction, and the third saturated fraction as catalytic cracking feedstock for the catalytic cracking reaction in step (5), or the hydrogenated component can be used as feedstock for producing high-octane gasoline components or aromatic components. In this preferred embodiment, in step (5), the catalytic cracking feedstock includes the first saturated fraction, the second saturated fraction, the third saturated fraction, butene obtained from the separation of gas products, and the hydrogenated component obtained from the hydrogenation reaction of the second unsaturated fraction from step (3). The catalytic cracking feedstock composed in this way can better prepare high-value products through catalytic cracking reaction, thereby further improving the yield of high-value products.

[0080] It should be noted that, in this embodiment, the conditions for the hydrogenation reaction of the second unsaturated fraction obtained from step (3) include a hydrogen partial pressure of 10.0-25.0 MPa, a reaction temperature of 330-450 °C, and a volume hourly space velocity of 0.1-2.0 h⁻¹. -1 Hydrogen-to-oil volume ratio 1000-2000 Nm 3 / m 3 The active metal component in the hydrogenation catalyst is selected from Group VIB metals and / or Group VIII non-noble metals, and the support is selected from one or more of alumina, silica, and amorphous silica-alumina. The Group VIB metal is molybdenum and / or tungsten, and the Group VIII non-noble metal is nickel and / or cobalt. Preferably, the active metal component is a combination of one or more of nickel-tungsten, nickel-tungsten-cobalt, nickel-molybdenum, or cobalt-molybdenum.

[0081] According to a specific embodiment of the process method described in the first aspect of the present invention, the conditions for the catalytic cracking reaction in step (5) include:

[0082] The catalytic cracking feedstock is mixed with steam and then fed into the reactor. The reaction temperature is 510-650℃, the reaction time is 1-20 seconds, the weight ratio of the catalyst to the catalytic cracking feedstock is (3-50):1, and the weight ratio of the steam to the catalytic cracking feedstock is (0.03-0.8):1; and / or,

[0083] The catalyst comprises the following components, based on a dry weight basis:

[0084] 1-50% zeolite, 5-99% inorganic oxides, and 0-70% clay;

[0085] The preferred composition is 5-45% zeolite, 10-80% inorganic oxides, and 5-60% clay.

[0086] More preferably, 10-40% by weight zeolite, 20-70% by weight inorganic oxides, and 10-50% by weight clay.

[0087] It should be noted that, in the process method of this application, by controlling the conditions of the catalytic cracking reaction in step (5) as described above, the catalytic cracking feedstock can be better reacted into high-value products such as low-carbon olefins (ethylene, propylene, butene) and light aromatics BTX (benzene, toluene and xylene) under the catalysis of the above catalyst, and the yield of high-value-added products can be further improved.

[0088] It should be noted that, in one embodiment, the zeolite includes mesoporous zeolite and optionally macroporous zeolite, wherein the mesoporous zeolite is selected from ZSM series zeolite, ZRP zeolite, and any combination thereof; and the macroporous zeolite is selected from rare earth Y-type zeolite, rare earth hydrogen Y-type zeolite, ultrastable Y-type zeolite, and high silica Y-type zeolite, and any combination thereof.

[0089] In one embodiment, the mesoporous zeolite accounts for 10-90% by weight, preferably 50-80% by weight, on a dry basis, of the total weight of the zeolite.

[0090] In this application, the terms mesoporous zeolite and macroporous zeolite are defined according to conventional definitions in the art, namely, the average pore size of mesoporous zeolite is about 0.5-0.6 nm, and the average pore size of macroporous zeolite is about 0.7-1.0 nm.

[0091] As an example, the macroporous zeolite may be selected from one or more of rare earth Y (REY) type zeolite, rare earth hydrogen Y (REHY) type zeolite, ultrastable Y type zeolite obtained by different methods, and high-silica Y type zeolite. The mesoporous zeolite may be selected from zeolites with an MFI structure, such as ZSM series zeolites and / or ZRP zeolite. Optionally, the above-mentioned mesoporous zeolites may be modified with non-metallic elements such as phosphorus and / or transition metal elements such as iron, cobalt, and nickel. A more detailed description of ZRP zeolite can be found in US Patent 5,232,675A. The ZSM series zeolites are preferably selected from one or more mixtures of ZSM-5, ZSM-11, ZSM-12, ZSM-23, ZSM-35, ZSM-38, ZSM-48, and other zeolites with similar structures. A more detailed description of ZSM-5 can be found in US Patent 3,702,886A.

[0092] It should be noted that the inorganic oxides used as binders are preferably silicon dioxide (SiO2) and / or aluminum oxide (Al2O3). The clay used as a matrix (i.e., carrier) is preferably kaolin and / or hydrous kaolin.

[0093] Secondly, the present invention relates to a system for producing high value-added products from crude oil, such as... Figure 1 As shown, the system includes a distillation unit 100, a first separation unit 201, a second separation unit 202, a third separation unit 203, and a catalytic cracking reaction unit 400;

[0094] The distillation unit 100 is provided with a crude oil inlet 101, a light distillate oil outlet 201a, a middle distillate oil outlet 202a and a heavy distillate oil outlet 203a.

[0095] The light distillate oil outlet 201a of the distillation unit 100 is connected to the material inlet of the first separation unit 201. The first separation unit 201 is also provided with a first saturated outlet 201b and a first unsaturated outlet 201c.

[0096] The middle distillate oil outlet 202a of the distillation unit 100 is connected to the material inlet of the second separation unit 202. The second separation unit 202 is also provided with a second saturated outlet 202b and a second unsaturated outlet 202c.

[0097] The heavy distillate oil outlet 203a of the distillation unit 100 is connected to the material inlet of the third separation unit 203. The third separation unit 203 is also provided with a third saturated outlet 203b and a third unsaturated outlet 203c.

[0098] The first saturated outlet 201b, the second saturated outlet 202b and the third saturated outlet 203b are respectively connected to the catalytic cracking feedstock inlet of the catalytic cracking reaction unit 400; the catalytic cracking reaction unit 400 is also provided with a cracked gas outlet 401, a cracked light gasoline outlet 402, a cracked heavy gasoline outlet 403, a cracked diesel outlet 404 and a cracked heavy oil outlet 405.

[0099] It should be noted that the process method described in the first aspect of the present invention can be based on, but is not limited to, the system described in the second aspect of the present invention, and the system described in the second aspect of the present invention can be operated based on, but is not limited to, the process method described in the first aspect of the present invention.

[0100] It should be noted that in the system of this application, crude oil enters the distillation unit 100 through crude oil inlet 101, and is distilled to obtain light distillate oil, middle distillate oil, and heavy distillate oil. The three types of oils obtained from the distillation unit 100 flow out of the distillation unit 100 through light distillate oil outlet 201a, middle distillate oil outlet 202a, and heavy distillate oil outlet 203a, respectively, and then enter the first separation unit 201, the second separation unit 202, and the third separation unit 203, respectively. The light distillate oil, middle distillate oil, and heavy distillate oil are separated in the three separation units. Specifically, the light distillate oil is separated into a first saturated fraction and a first unsaturated fraction in the first separation unit 201, the middle distillate oil is separated into a second saturated fraction and a second unsaturated fraction in the second separation unit 202, and the heavy distillate oil is separated into a third saturated fraction and a third unsaturated fraction in the third separation unit 203. The first saturated fraction flows out through the first saturated fraction outlet 201b and then enters the catalytic cracking reaction unit 400 through the catalytic cracking feedstock inlet. The second saturated fraction flows out through the second saturated fraction outlet 202b and then enters the catalytic cracking reaction unit 400 through the catalytic cracking feedstock inlet. The third saturated fraction flows out through the third saturated fraction outlet 203b and then enters the catalytic cracking reaction unit 400 through the catalytic cracking feedstock inlet. The three saturated fractions, as catalytic cracking feedstocks, are in contact with the catalyst in the catalytic cracking reaction unit 400 and undergo catalytic cracking reaction at high temperature. They are then separated sequentially by oil-gas separation equipment and oil-gas separation equipment to obtain cracked gas, cracked light gasoline, cracked heavy gasoline, cracked diesel, and cracked heavy oil. The above products flow out through cracked gas outlet 401, cracked light gasoline outlet 402, cracked heavy gasoline outlet 403, cracked diesel outlet 404, and cracked heavy oil outlet 405, respectively.

[0101] It should be noted that the system of this application first distills and cuts the feed oil through the distillation unit 100, and then separates the three types of distillate products obtained by the separation through three separation units. The three saturated fractions obtained by separation are used together as feedstock for catalytic cracking in the catalytic cracking reaction unit 400 to carry out catalytic cracking, so that the crude oil can be better converted into high-value products such as low-carbon olefins (ethylene, propylene, butene) and light aromatics BTX (benzene, toluene and xylene).

[0102] It should be noted that in the crude oil production system of the present invention, oil-agent separation equipment and reaction product separation equipment may also be provided. The oil-agent separation equipment and reaction product separation equipment are well known to those skilled in the art. For example, the oil-agent separation equipment may include cyclone separators, settling tanks and strippers, while the reaction product separation equipment may be fractionation towers.

[0103] According to a specific embodiment of the system described in the second aspect of the present invention, the system further includes an aromatics production unit, wherein the first unsaturated outlet 201c is connected to the feed inlet of the aromatics production unit; and / or,

[0104] The system also includes a high-octane gasoline production unit, wherein the second unsaturated outlet 202c is connected to the feed inlet of the high-octane gasoline production unit and / or the feed inlet of the aromatics production unit; and / or,

[0105] The system also includes a needle coke production unit and a road asphalt production unit, wherein the third unsaturated outlet 203c is connected to the raw material inlet of the needle coke production unit and / or the raw material inlet of the road asphalt production unit; and / or,

[0106] The system also includes a gas separation unit. The pyrolysis gas outlet 401 of the catalytic cracking reaction unit 400 is connected to the gas inlet to be separated of the gas separation unit. The gas separation unit is also provided with an ethylene outlet, a propylene outlet, a butene outlet and a residual component outlet.

[0107] It should be noted that light distillate oil is separated into a first saturated fraction and a first unsaturated fraction by the first separation unit 201. The first unsaturated fraction can flow out through the first unsaturated fraction outlet 201c and enter the aromatics production unit as feedstock to produce aromatics. Middle distillate oil is separated into a second saturated fraction and a second unsaturated fraction by the second separation unit 202. The second unsaturated fraction can flow out through the second unsaturated fraction outlet 202c and enter the high-octane gasoline production unit as feedstock to produce high-octane gasoline, or it can enter the aromatics production unit as feedstock to produce aromatics. Heavy distillate oil is separated into a third saturated fraction and a third unsaturated fraction by the third separation unit 203. The third unsaturated fraction can flow out through the third unsaturated fraction outlet 203c and enter the needle coke production unit as feedstock to produce needle coke, or it can enter the road asphalt production unit as feedstock to produce road asphalt.

[0108] It should be noted that the pyrolysis gas exiting from pyrolysis gas outlet 401 is separated by a gas separation unit to obtain ethylene, propylene, butene, and residual components. The system of this application enables the efficient utilization of all components.

[0109] According to another specific embodiment of the system described in the second aspect of the present invention, the catalytic cracking reaction unit 400 is further provided with a difficult-to-convert component inlet 406, which is connected to the cracked light gasoline outlet 402 and / or the butene outlet of the gas separation unit.

[0110] It should be noted that, in a preferred embodiment, the cracked light gasoline flows out of the cracked light gasoline outlet 402 and then enters the catalytic cracking reaction unit 400 through the difficult-to-convert component inlet 406 as a catalytic cracking feedstock for the catalytic cracking reaction. The butene separated by the gas separation unit flows out of the butene outlet and then enters the catalytic cracking reaction unit 400 through the difficult-to-convert component inlet 406 as a catalytic cracking feedstock for the catalytic cracking reaction. Using the aforementioned butene and / or cracked light gasoline as partial catalytic cracking feedstock allows the catalytic cracking reaction to proceed more effectively and can further improve the yield of high-value products.

[0111] It should be noted that, as a variation of the implementation, the difficult-to-convert component inlet 406 can be connected to the gaseous hydrocarbon outlet rich in C4 fractions of other external units, or to the light distillate oil outlet with a final boiling point of less than 280-360°C of other external units. Specifically, it can be connected to one or more outlets of other primary processing units, such as straight-run naphtha outlet, straight-run kerosene outlet, and straight-run diesel outlet, or to one or more outlets of other secondary processing units, such as topping oil outlet, residue oil outlet, hydrocracking light naphtha outlet, pentane oil outlet, coking gasoline outlet, Fischer-Tropsch synthesis oil outlet, catalytic cracking light gasoline outlet, hydrotreated gasoline outlet, and hydrotreated diesel outlet.

[0112] It should be noted that there can be one, two, or more difficult-to-convert component inlets 406. In one embodiment, when there is one difficult-to-convert component inlet 406, light hydrocarbons and light distillate oils, which are difficult-to-convert components, can enter the catalytic cracking reaction unit through the same difficult-to-convert component inlet 406. In another preferred embodiment, there are two or more difficult-to-convert component inlets 406, and light hydrocarbons and light distillate oils, which are difficult-to-convert components, enter the catalytic cracking reactor through different difficult-to-convert component inlets 406. Specifically, light hydrocarbons are introduced into the catalytic cracking reactor through one or more difficult-to-convert component inlets 406 downstream of the light distillate oil difficult-to-convert component inlet 406 (introduction position), which is beneficial to obtain high-value products with higher yields.

[0113] It should be noted that, in one embodiment, the catalytic cracking reactor is provided with one or more, for example, one, two or more inlets for difficult-to-convert components, and the one or more inlets for difficult-to-convert components can be independently located in the lower part of the catalytic cracking reactor. More preferably, the inlets for difficult-to-convert components are each independently located in the middle and upper reaches of the catalytic cracking reactor.

[0114] According to another specific embodiment of the system described in the second aspect of the present invention, the system is further provided with a hydrogenation reaction unit 300, wherein the second unsaturated outlet 202c is connected to the hydrogenation feedstock inlet of the hydrogenation reaction unit 300, and the hydrogenation product outlet 301 of the hydrogenation reaction unit 300 is connected to the catalytic cracking feedstock inlet of the catalytic cracking reaction unit 400.

[0115] In a preferred embodiment, the middle distillate oil is separated into a second saturated fraction and a second unsaturated fraction via a second separation unit 202. The second unsaturated fraction enters a hydrogenation reaction unit 300, where it undergoes a hydrogenation reaction in the presence of hydrogen and a hydrogenation catalyst. The hydrogenated product of the second unsaturated fraction flows out through a hydrogenation product outlet 301 and is then used as feedstock for catalytic cracking in a catalytic cracking reaction unit 400. In this preferred embodiment, the hydrogenated product of the second unsaturated fraction, along with the three saturated fractions (and possibly butene obtained from gas separation), is used as feedstock for catalytic cracking, which can further increase the yield of high-value products.

[0116] According to a specific embodiment of the system described in the second aspect of the present invention, the first separation unit 201 is an extraction separation unit, the second separation unit 202 is an extraction separation unit, and the third separation unit 203 is a supercritical extraction separation unit;

[0117] The catalytic cracking reaction unit 400 is selected from one or a combination of several reactors, including fluidized bed, turbulent bed, fast bed and dilute phase transport bed; the reactor is selected from one or a combination of two of the following: constant linear velocity reactor, constant diameter reactor, variable diameter reactor, upward transport line reactor and downward transport line reactor.

[0118] It should be noted that in the system of this application, an extraction separation unit and a supercritical extraction separation unit are used in combination, and the catalytic cracking reaction unit (reactor) is selected from the above-mentioned reactor, so that the separation process and the catalytic cracking reaction process can operate better, thereby improving the yield of high-value products of the system.

[0119] It should be noted that, in order to ensure the feedstock oil reacts fully and depending on the different quality requirements of the target product, the catalytic cracking reaction unit can have 2-8 reaction zones, preferably 2-3. The gas velocity in the turbulent bed and fast bed reactors is 0.1 m / s to 2 m / s, and the gas velocity in the dilute phase transport bed is 2 m / s to 20 m / s.

[0120] Figure 1 A preferred embodiment of the system for producing high value-added products from crude oil according to this application is provided.

[0121] like Figure 1As shown, crude oil enters the distillation unit 100 through crude oil inlet 101 and is separated into light distillate oil, middle distillate oil and heavy distillate oil under the action of heat;

[0122] The separated light distillate oil flows out through light distillate oil outlet 201a and enters the first separation unit 201, where it contacts the extraction solvent and achieves component separation to obtain a first saturated fraction and a first unsaturated fraction. The first saturated fraction flows out through the first saturated fraction outlet 201b and enters the catalytic cracking reaction unit 400; the first unsaturated fraction flows out through the first unsaturated fraction outlet 201c and is used as a feedstock for aromatics production.

[0123] The separated middle distillate oil flows out through middle distillate oil outlet 202a and enters the second separation unit 202, where it contacts the extraction solvent and achieves component separation to obtain a second saturated fraction and a second unsaturated fraction. The second saturated fraction flows out through the second saturated fraction outlet 202b and enters the catalytic cracking reaction unit 400. The second unsaturated fraction flows out through the second unsaturated fraction outlet 202c and is used as a feedstock for the production of high-octane gasoline components or aromatic components. Optionally, the second unsaturated fraction flows out through the second unsaturated fraction outlet 202c and is sent to the hydrogenation reaction unit 300 for hydrogenation treatment under the action of hydrogen and hydrogenation catalyst. The resulting hydrogenated second unsaturated fraction flows out through the hydrogenation product outlet 301 and is sent to the catalytic cracking reaction unit 400.

[0124] The separated heavy distillate oil flows out through heavy distillate oil outlet 203a and enters the third separation unit 203, where it contacts the extraction solvent and achieves component separation to obtain a third saturated fraction and a third unsaturated fraction. The third saturated fraction flows out through the third saturated fraction outlet 203b and is sent to the catalytic cracking reaction unit 400; the third unsaturated fraction is sent out of the device through the third unsaturated fraction outlet 203c as a raw material for the production of needle coke or road asphalt.

[0125] The first saturated fraction from the first saturated fraction outlet 201b, the second saturated fraction from the second saturated fraction outlet 202b, and the third saturated fraction from the third saturated fraction outlet 203b, along with an optional recalcitrant component from the recalcitrant component inlet 406, enter the catalytic cracking reaction unit 400. Under the action of heat and the catalytic cracking catalyst, a catalytic cracking reaction occurs. The reaction products are separated to obtain cracked gas (cracked gas outlet 401), cracked light gasoline (cracked light gasoline outlet 402), cracked heavy gasoline (cracked heavy gasoline outlet 403), cracked diesel (cracked diesel outlet 404), and cracked heavy oil (cracked heavy oil outlet 405). Further separation of the cracked gas can yield ethylene, propylene, butene, and other products.

[0126] The present invention will be further described in detail below through examples, but these examples are not intended to limit the invention. In the following examples, unless otherwise specified, the experimental instruments and raw materials involved are all commercially available products.

[0127] The feedstock used in the following examples and comparative examples is Kuwaiti crude oil, the properties of which are shown in Table 1. The catalyst used in the catalytic cracking unit is a commercial catalytic cracking catalyst purchased from the Catalyst Division of China Petroleum & Chemical Corporation (Sinopec), with the trade name DMMC-2. The trade name of the hydrotreating catalyst is RN-32L.

[0128] Table 1 Properties of the crude oil used

[0129]

[0130] The yield of high value-added products refers to the total yield of low-carbon olefins (ethylene, propylene, butene), light aromatics (BTX, benzene, toluene, and xylene), aromatic components (first unsaturated fraction), high-octane gasoline components (second unsaturated fraction), and needle coke or road asphalt components (third unsaturated fraction). The yield of a certain product can also refer to the weight percentage of that product in crude oil.

[0131] Example 1

[0132] The Kuwaiti crude oil in Table 1 was subjected to true boiling point distillation to separate light distillate, middle distillate, and heavy distillate. The cutoff point between the light distillate and the middle distillate was 200℃, and the cutoff point between the middle distillate and the heavy distillate was 300℃. The light distillate was extracted in the first separation unit using sulfolane as a solvent to obtain a first saturated fraction and a first unsaturated fraction. The yield of the first saturated fraction was 90.6%, and the mass fraction of saturated hydrocarbons in the first saturated fraction was 95.55%. The mass fraction of aromatics in the first unsaturated fraction was 95.86%, making it a high-quality feedstock for producing aromatic components.

[0133] The middle distillate oil is extracted and separated in the second separation unit using an ionic liquid as the solvent. The cation is a dialkyl-substituted imidazole cation, the alkyl groups are methyl and hexyl, and the anion is a hexafluorophosphate anion. The extraction yields a second saturated fraction and a second unsaturated fraction. The yield of the second saturated fraction is 83%, the mass fraction of saturated hydrocarbons in the second saturated fraction is 87.4%, and the mass fraction of aromatics in the second unsaturated fraction is 92.4%. It is a high-quality feedstock for producing high-octane gasoline components or aromatic components.

[0134] The heavy distillate oil is fed into the third separation unit where propane is used as a solvent. Supercritical extraction is used to separate the third saturated fraction and the third unsaturated fraction. The yield of the third saturated fraction is 76.2%, the mass fraction of saturated hydrocarbons in the third saturated fraction is 52.4%, and the heavy metal removal rate is over 96%. The third unsaturated fraction can be used as a raw material for road asphalt.

[0135] Catalytic cracking experiments were conducted using a fluidized bed reactor for different distillation range saturated fractions. Before the experiment, the catalyst was loaded into the reactor and kept in a fluidized state while the reactor was heated to the reaction temperature. Catalytic cracking feedstock, including the first, second, and third saturated fractions and the difficult-to-convert light gasoline component (derived from cracked light gasoline obtained through liquid product separation), was fed into the fluidized bed reactor. The feedstock, after preheating, was mixed with high-temperature steam and introduced into the bottom of the fluidized bed through the feed nozzle. The difficult-to-convert butene component (derived from gaseous product separation) entered the bottom of the fluidized bed reactor through the feed nozzle from the gas feed line. All reactants reacted on the hot catalyst. After the reaction, steam was introduced for stripping. The reaction oil and gas then entered a multi-stage condensation and separation system for separation, yielding cracked gaseous and liquid products. The yields of both gaseous and liquid products were measured. The gaseous products were further separated to obtain ethylene, propylene, butene, and residual components. After the reaction, the reactor automatically heats up to the regeneration temperature, and oxygen is simultaneously introduced into the reactor to regenerate the spent catalyst through coking. The real-time CO2 concentration of the regenerated flue gas is measured by an infrared analyzer, and the coke yield is calculated based on the integral of the flue gas flow rate. The gaseous products are collected and their composition is analyzed by offline chromatography, while the liquid products are analyzed by simulated distillation chromatography to obtain the mass fractions of cracked gasoline (cracking light gasoline and cracked heavy gasoline), cracked diesel, and cracked heavy oil.

[0136] The reaction conditions and product yields for different units are listed in Tables 2 and 3. As can be seen from Table 3, the ethylene yield in this embodiment reached 12.80% by weight, the propylene yield reached 26.01% by weight, the high value-added product yield reached 70.79% by weight, and the coke yield was 9.10% by weight.

[0137] Example 2

[0138] The Kuwaiti crude oil in Table 1 was subjected to true boiling point distillation to separate light distillate, middle distillate, and heavy distillate. The cutoff point between the light distillate and the middle distillate was 200℃, and the cutoff point between the middle distillate and the heavy distillate was 300℃. The light distillate was extracted in the first separation unit using sulfolane as a solvent to obtain a first saturated fraction and a first unsaturated fraction. The yield of the first saturated fraction was 90.6%, and the mass fraction of saturated hydrocarbons in the first saturated fraction was 95.55%. The mass fraction of aromatics in the first unsaturated fraction was 95.86%, making it a high-quality feedstock for producing aromatic components.

[0139] The middle distillate oil is extracted and separated in the second separation unit using an ionic liquid as the solvent. The cation is a dialkyl-substituted imidazole cation, the alkyl groups are methyl and hexyl, and the anion is a hexafluorophosphate anion. The extraction yields a second saturated fraction and a second unsaturated fraction. The yield of the second saturated fraction is 83%, the mass fraction of saturated hydrocarbons in the second saturated fraction is 87.4%, and the mass fraction of aromatics in the second unsaturated fraction is 92.4%. It is a high-quality feedstock for producing high-octane gasoline components or aromatic components.

[0140] The second unsaturated fraction is fed into the hydrogenation unit, where it is upgraded and then sent back to the fluidized bed reactor of the catalytic cracking unit for further conversion into high-value products.

[0141] The heavy distillate oil is fed into the third separation unit where propane is used as a solvent. Supercritical extraction is used to separate the third saturated fraction and the third unsaturated fraction. The yield of the third saturated fraction is 76.2%, the mass fraction of saturated hydrocarbons in the third saturated fraction is 52.4%, and the heavy metal removal rate is over 96%. The third unsaturated fraction can be used as a raw material for road asphalt.

[0142] Catalytic cracking experiments were conducted using a fluidized bed reactor for saturated fractions with different distillation ranges. Before the experiment, the catalyst was loaded into the reactor and kept in a fluidized state while the reactor was heated to the reaction temperature. Catalytic cracking feedstock, including the first saturated fraction, the second saturated fraction, the hydrogenated second unsaturated fraction, the third saturated fraction, and the difficult-to-convert component light gasoline (derived from cracked light gasoline obtained through liquid product separation), was fed into the fluidized bed reactor. The feedstock, after preheating, was mixed with high-temperature steam and introduced into the bottom of the fluidized bed through the feed nozzle. The difficult-to-convert component butene (derived from gaseous product separation) entered the bottom of the fluidized bed reactor through the gas feed line via the feed nozzle. All reactants reacted on the hot catalyst. After the reaction, steam was introduced for stripping. The reaction oil and gas then entered a multi-stage condensation and separation system for separation, yielding cracked gaseous and liquid products. The yields of both gaseous and liquid products were measured. The gaseous products were further separated to obtain ethylene, propylene, butene, and residual components. After the reaction, the reactor automatically heats up to the regeneration temperature, and oxygen is simultaneously introduced into the reactor to regenerate the spent catalyst through coking. The real-time CO2 concentration of the regenerated flue gas is measured by an infrared analyzer, and the coke yield is calculated based on the integral of the flue gas flow rate. The gaseous products are collected and their composition is analyzed by offline chromatography, while the liquid products are analyzed by simulated distillation chromatography to obtain the mass fractions of cracked gasoline (cracking light gasoline and cracked heavy gasoline), cracked diesel, and cracked heavy oil.

[0143] The reaction conditions and product yields for different units are listed in Tables 2 and 3. As can be seen from Table 3, the ethylene yield in this embodiment reached 12.85 wt%, the propylene yield reached 26.35 wt%, the high value-added product yield reached 70.67 wt%, and the coke yield was 9.16 wt%.

[0144] Comparative Example 1

[0145] This comparative example is a direct catalytic cracking experiment of crude oil. Kuwaiti crude oil and DMMC-2 catalyst, as shown in Table 1, were used in a fixed fluidized bed reactor. Before the experiment, the catalyst was loaded into the reactor, and the reactor was heated to the reaction temperature while maintaining the catalyst in a fluidized state. The preheated crude oil was mixed with high-temperature steam and fed into the bottom of the fluidized bed through the feed nozzle, where it reacted on the hot catalyst. After the reaction, steam was introduced for stripping, and the reaction oil and gas entered a multi-stage condensation and separation system for separation, yielding cracked gaseous and liquid products. The yields of both gaseous and liquid products were measured. After the reaction, the reactor was automatically heated to the regeneration temperature, and oxygen was simultaneously introduced into the reactor for coke regeneration of the spent catalyst. The real-time CO2 concentration of the regenerated flue gas was measured using an infrared analyzer, and the coke yield was calculated based on the integral of the flue gas flow rate. The gaseous products were collected and their composition was analyzed using offline chromatography, while the liquid products were analyzed using simulated distillation chromatography to obtain the mass fractions of cracked gasoline, cracked diesel, and cracked heavy oil. The reaction conditions and product distribution are listed in Tables 2 and 3.

[0146] As can be seen from the results in Table 3, the yield of ethylene in this comparative example is only 5.56 wt%, the yield of propylene is only 15.85 wt%, the yield of high value-added products is 39.04 wt%, and the yield of coke is 13.12 wt%.

[0147] Comparative Example 2

[0148] Kuwaiti crude oil was separated into light distillate, middle distillate, and heavy distillate by true boiling point distillation. The cutoff point between the light distillate and the middle distillate was 200°C, and the cutoff point between the middle distillate and the heavy distillate was 300°C.

[0149] Catalytic cracking experiments of crude oil fractions with different distillation ranges were conducted using a fluidized bed reactor. Before the experiment, the catalyst was loaded into the reactor and heated to the reaction temperature while maintaining the catalyst in a fluidized state. Crude oil fractions with different distillation ranges were mixed with high-temperature steam in the order of light distillate, middle distillate, and heavy distillate, and after preheating, the mixture was introduced into the bottom of the fluidized bed through the feed nozzle, where it reacted on the hot catalyst. After the reaction, steam was introduced for stripping, and the reaction oil and gas were separated in a multi-stage condensation and separation system to obtain cracked gaseous and liquid products. The yields of both gaseous and liquid products were measured. After the reaction, the reactor was automatically heated to the regeneration temperature, and oxygen was introduced into the reactor to regenerate the catalyst. The real-time CO2 concentration of the regenerated flue gas was measured by an infrared analyzer, and the coke yield was calculated based on the flue gas flow rate integral. The gaseous products were collected and analyzed for compositional distribution using offline chromatography, while the liquid products were analyzed using simulated distillation chromatography to obtain the mass fractions of cracked gasoline, cracked diesel, and cracked heavy oil. The reaction conditions and product distribution are listed in Tables 2 and 3.

[0150] As can be seen from the results in Table 3, the yield of ethylene in this comparative example is only 7.61% by weight, the yield of propylene is only 17.30% by weight, the yield of high value-added products is 43.76%, and the yield of coke is 11.26% by weight.

[0151] Table 2 Reaction conditions of Examples 1-2 and Comparative Examples 1-2

[0152]

[0153] In Table 2, the water vapor usage (by weight%) indicates the proportion of water vapor in the total weight of the catalytic cracking feedstock.

[0154] The amount of catalytic cracking feedstock does not include the difficult-to-convert components (butene and cracked light gasoline) in the following weight ratios: catalyst to catalytic cracking feedstock, proportion of difficult-to-convert components in catalytic cracking feedstock, and proportion of hydrogenated second unsaturated component in catalytic cracking feedstock.

[0155] Table 3 Comparison of reaction results between Examples 1-2 and Comparative Examples 1-2

[0156]

[0157] In Example 2, based on the weight of crude oil, the yield of the second unsaturated fraction is 1.77 wt%. After being hydrogenated by the hydrogenation unit, this fraction is sent to the catalytic cracking unit to undergo a cracking reaction to convert into high-value-added products. Therefore, the yield of high-value-added products in Example 2 is not included in the weight of the second unsaturated fraction.

[0158] As can be seen from the results of the above embodiments and comparative examples, when crude oil catalytic cracking reaction is carried out using the catalytic cracking method and system of this application, the yields of ethylene and propylene are significantly improved, the yield of high value-added products is high, that is, the crude oil atom utilization rate is high.

[0159] In the description of this application, it should be noted that the terms "upper", "lower", "inner", "outer", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship in the working state of this application. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0160] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0161] The present application has been described above with reference to preferred embodiments; however, these embodiments are merely exemplary and illustrative. Various substitutions and modifications can be made to the present application based on these embodiments, all of which fall within the protection scope of the present application.

Claims

1. A process for producing high value-added products from crude oil, characterized in that, The process includes the following steps: (1) Distilling crude oil to obtain light oil, intermediate oil and heavy oil; wherein the cutting point of the light oil and the intermediate oil is 160-220℃, and the cutting point of the intermediate oil and the heavy oil is 260-320℃. (2) The light oil is subjected to a first separation to obtain a first saturated fraction and a first unsaturated fraction; (3) The intermediate oil is subjected to a second separation to obtain a second saturated fraction and a second unsaturated fraction; (4) The heavy oil is subjected to a third separation to obtain a third saturated fraction and a third unsaturated fraction; (5) The catalytic cracking feedstock is brought into contact with the catalyst to carry out the catalytic cracking reaction, and the cracked gas, cracked light gasoline, cracked heavy gasoline, cracked diesel and cracked heavy oil are obtained by oil-gas separation; The catalytic cracking feedstock comprises the first saturated component, the second saturated component, and the third saturated component.

2. The process method according to claim 1, characterized in that, The crude oil mentioned in step (1) is selected from one or more of the following: intermediate-based crude oil, intermediate-naphthenic crude oil, and naphthenic-intermediate crude oil.

3. The process method according to claim 1, characterized in that, The first separation in step (2) includes: contacting the light oil with a first solvent to perform a first extraction separation; The first solvent is selected from one or more combinations of sulfolane, methyl sulfolane, dimethyl sulfolane, and polyethylene glycol ether solvents; The conditions for the first extraction and separation include: a temperature of 60-180℃, a pressure of 0.3-1.2 MPa, and a weight ratio of the first solvent to the light oil of (1-6):

1.

4. The process method according to claim 1, characterized in that, The second separation in step (3) includes: contacting the intermediate oil with an ionic liquid or a second solvent to perform a second extraction separation; The thermal stability of the ionic liquid is higher than 250℃; The ionic liquid comprises cations and anions; the cations are selected from alkyl-substituted imidazoles and / or pyridines; the anions are selected from at least one of hexafluorophosphate, tetrafluoroborate, and bis(trifluoromethanesulfonyl)imide. The second solvent is selected from one or more combinations of furfural, dimethyl sulfoxide, N,N-dimethylformamide, N,N-diethylformamide and morpholine; The conditions for the second extraction and separation include: a temperature of 15-120°C, a pressure of 0.1-0.5 MPa, and the weight ratio of the ionic liquid to the intermediate oil, or the weight ratio of the second solvent to the intermediate oil, being independently (1-15):

1.

5. The process method according to claim 1, characterized in that, The third separation in step (4) includes: contacting the heavy oil with a third solvent to perform supercritical extraction separation; The third solvent is selected from one or a mixture of several of propylene, ethane, propane, n-butane, isobutane, n-pentane, isopentane, hexane, heptane, and octane; The conditions for supercritical extraction separation include: a temperature of 50-100℃, a pressure of 6-20 MPa, and a weight ratio of the third solvent to the heavy oil of (2-5):

1.

6. The process method according to claim 1, characterized in that, The process method further includes the following steps: This allows the first unsaturated fraction from step (2) to be used as a raw material for the production of aromatics; and / or, This allows the second unsaturated fraction from step (3) to be used as a feedstock for the production of high-octane gasoline and / or aromatics; and / or, This allows the third unsaturated fraction from step (4) to be used as a raw material for the production of needle coke and / or road asphalt; and / or, This allows the pyrolysis gas from step (5) to be separated to obtain ethylene, propylene, butene and the remaining components.

7. The process method according to claim 1, characterized in that, The catalytic cracking feedstock also contains recalcitrant components, including light hydrocarbons and / or light distillate oils.

8. The process method according to claim 7, characterized in that, The light hydrocarbons of the difficult-to-convert components include gaseous hydrocarbon products rich in C4 fractions; The light distillate oils containing the difficult-to-convert components include self-produced light distillate oils with a final boiling point of less than 280-360°C.

9. The process method according to claim 8, characterized in that, The process method further includes the following steps: This causes the second unsaturated fraction from step (3) to undergo a hydrogenation reaction, yielding a hydrogenated fraction; The catalytic cracking feedstock in step (5) also includes the hydrogenation component; The hydrogenation component accounts for 0.1-10% by weight in the catalytic cracking feedstock.

10. The process method according to claim 1, characterized in that, The conditions for the catalytic cracking reaction described in step (5) include: The catalytic cracking feedstock is mixed with steam and then fed into the reactor. The reaction temperature is 510-650℃, the reaction time is 1-20 seconds, the weight ratio of the catalyst to the catalytic cracking feedstock is (3-50):1, and the weight ratio of the steam to the catalytic cracking feedstock is (0.03-0.8):1; and / or, The catalyst comprises the following components, based on a dry weight basis: 1-50% zeolite, 5-99% inorganic oxides, and 0-70% clay.

11. The process method according to claim 8, characterized in that, The light hydrocarbons of the difficult-to-convert component include butene obtained by separating the pyrolysis gas; and / or Butene, as the difficult-to-convert component, accounts for 5-20% by weight in the catalytic cracking feedstock.

12. The process method according to claim 8, characterized in that, The light hydrocarbons of the difficult-to-convert components include one or more of the following fractions: straight-run naphtha, straight-run kerosene, and straight-run diesel produced by other primary processing units; topping oil, residue oil, hydrocracked light naphtha, pentane oil, coking gasoline, Fischer-Tropsch synthetic oil, catalytic cracked light gasoline, hydrotreated gasoline, and hydrotreated diesel produced by other secondary processing units.

13. The process method according to claim 8, characterized in that, The light distillate oil containing the difficult-to-convert components includes the cracked light gasoline obtained from step (5); and / or The weight percentage of cracked light gasoline, which is the difficult-to-convert component, in the catalytic cracking feedstock is 5-20%.

14. The process method according to claim 10, characterized in that, The catalyst comprises the following components, based on a dry weight basis: 5-45% zeolite, 10-80% inorganic oxides, and 5-60% clay.

15. The process method according to claim 10, characterized in that, The catalyst comprises the following components, based on a dry weight basis: 10-40 wt% zeolite, 20-70 wt% inorganic oxides, and 10-50 wt% clay.

16. A system for producing high value-added products from crude oil, characterized in that, The system includes a distillation unit (100), a first separation unit (201), a second separation unit (202), a third separation unit (203), and a catalytic cracking reaction unit (400). The distillation unit (100) is provided with a crude oil inlet (101), a light distillate oil outlet (201a), a middle distillate oil outlet (202a) and a heavy distillate oil outlet (203a). The light distillate oil outlet (201a) of the distillation unit (100) is connected to the material inlet of the first separation unit (201). The first separation unit (201) is also provided with a first saturated outlet (201b) and a first unsaturated outlet (201c). The middle distillate oil outlet (202a) of the distillation unit (100) is connected to the material inlet of the second separation unit (202), and the second separation unit (202) is also provided with a second saturated outlet (202b) and a second unsaturated outlet (202c). The heavy distillate oil outlet (203a) of the distillation unit (100) is connected to the material inlet of the third separation unit (203). The third separation unit (203) is also provided with a third saturated outlet (203b) and a third unsaturated outlet (203c). The first saturated outlet (201b), the second saturated outlet (202b) and the third saturated outlet (203b) are respectively connected to the catalytic cracking feedstock inlet of the catalytic cracking reaction unit (400); the catalytic cracking reaction unit (400) is also provided with a cracked gas outlet (401), a cracked light gasoline outlet (402), a cracked heavy gasoline outlet (403), a cracked diesel outlet (404) and a cracked heavy oil outlet (405).

17. The system according to claim 16, characterized in that, The system also includes an aromatics production unit, wherein the first unsaturated outlet (201c) is connected to the feed inlet of the aromatics production unit; and / or, The system also includes a high-octane gasoline production unit, wherein the second unsaturated outlet (202c) is connected to the feed inlet of the high-octane gasoline production unit and / or the feed inlet of the aromatics production unit; and / or, The system also includes a needle coke production unit and a road asphalt production unit, wherein the third unsaturated outlet (203c) is connected to the raw material inlet of the needle coke production unit and / or the raw material inlet of the road asphalt production unit; and / or, The system also includes a gas separation unit. The pyrolysis gas outlet (401) of the catalytic cracking reaction unit (400) is connected to the gas inlet to be separated of the gas separation unit. The gas separation unit is also provided with an ethylene outlet, a propylene outlet, a butene outlet and a residual component outlet.

18. The system according to claim 17, characterized in that, The catalytic cracking reaction unit (400) is further provided with a difficult-to-convert component inlet (406), which is connected to the cracked light gasoline outlet (402) and / or the butene outlet of the gas separation unit; and / or, The system is also provided with a hydrogenation reaction unit (300), the second unsaturated outlet (202c) is connected to the hydrogenation feedstock inlet of the hydrogenation reaction unit (300), and the hydrogenation product outlet (301) of the hydrogenation reaction unit (300) is connected to the catalytic cracking feedstock inlet of the catalytic cracking reaction unit (400).

19. The system according to claim 16, characterized in that, The first separation unit (201) is an extraction separation unit, the second separation unit (202) is an extraction separation unit, and the third separation unit (203) is a supercritical extraction separation unit; The catalytic cracking reaction unit (400) is selected from one or a combination of several reactors, including fluidized bed, turbulent bed, fast bed and dilute phase transport bed; the reactor is selected from one or a combination of two of the following reactors in series: constant linear velocity reactor, constant diameter reactor, variable diameter reactor, upward transport line reactor and downward transport line reactor.

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