Method and system for producing high-value product with high crude oil utilization rate

Abstract

The invention relates to a method and system for producing high-value products with high crude oil utilization rate, and the method comprises the following steps: (1) carrying out distillation cutting on crude oil to obtain crude oil light fractions and crude oil heavy fractions; (2) carrying out extraction separation on the crude oil heavy fraction to obtain extract oil of the crude oil heavy fraction and raffinate oil of the crude oil heavy fraction; (3) contacting the catalytic cracking raw material with a catalyst in a catalytic cracking reactor to carry out catalytic cracking reaction, and carrying out oil-gas separation to obtain cracked gas, cracked light gasoline, cracked heavy gasoline, cracked diesel oil and cracked heavy oil; the catalytic cracking raw materials comprise the crude oil light fraction, extract oil of the crude oil heavy fraction and components difficult to convert. According to the invention, a method combining crude oil component separation and catalytic cracking reaction is adopted, so that intermediate base crude oil or naphthenic base crude oil with poorer quality can be converted into a high-value product, and the yield of the high-value product in the whole process is close to 65% or above.

Description

Technical Field

[0001] The invention relates to the field of petrochemical industry, and in particular to a method and system for producing high-value products with high crude oil utilization rate. Background Art

[0002] Refining capacity is in excess, and demand for refined oil products is slowing down. Ethylene, propylene and BTX (benzene-toluene-xylene) are key basic organic synthetic raw materials with huge demand, while demand for chemical products remains strong. The existing technical route for producing propylene and BTX from petroleum is developed on the basis of the traditional petroleum refining process that mainly produces oil products. There are problems such as long production process, low yield of high-value products and insignificant economic benefits. The technical measures to solve this problem are to develop key core technologies that mainly produce high-value products and can direct the conversion of crude oil hydrocarbon molecules into high-value products. Therefore, in recent years, international petrochemical companies represented by ExxonMobil and Saudi Aramco have begun to innovate traditional refining processes. These companies have subverted the traditional refining process and promoted the integration of refining and chemical to a new level of directly producing high-value products from crude oil.

[0003] ExxonMobil Corporation of the United States is a pioneer in the research and development of crude oil steam cracking to produce olefins, and is the first company to build an industrial demonstration unit. It has also applied for a series of patents, such as CN200580016314.X. The company's process for directly producing high-value products from crude oil is that the crude oil directly enters the steam cracking furnace, and the light components and recombinant components are separated by flash evaporation. The light components (gaseous components) enter the steam cracking furnace for cracking, and the heavy components (liquid components) are used as refinery raw materials. If the selected crude oil is light enough, there is no fraction above 593°C, that is, no bottom residue oil, and it does not need to rely on a refinery. The company's first industrial unit uses ultra-light paraffin-based tapis crude oil with an API gravity of 42.7 as raw material.

[0004] The technical characteristics of Saudi Aramco National Oil Company are that it adopts crude oil pretreatment technology and hydroprocessing technology to minimize the impact of non-volatile components in crude oil on steam cracking. At the same time, a vapor-liquid (steam and liquid) separation device is installed between the convection section and the radiation section of the steam cracking furnace to remove non-volatile liquid (liquid phase), ensuring that the material entering the radiation section does not carry liquid, thereby ensuring that the furnace tube does not coke, and the heavy components enter the catalytic cracking unit. It can be said that it is a process for producing olefins and aromatics from crude oil that integrates hydroprocessing, steam cracking and catalytic cracking processes.

[0005] Due to the presence of heavy components in crude oil that are difficult to vaporize, the existing technology for directly producing high-value products from crude oil is only suitable for low-sulfur paraffin-based crude oil with an API degree of about 45. Other crude oil-to-chemical technologies vary according to the different processing processes for heavy components in crude oil. The crude oil-to-chemical technology routes of major companies are different, but they all use fraction cutting and combine process technologies according to the properties of distillates with different distillation ranges to achieve crude oil production of high-value products. Compared with the traditional refining process, only the distillation range and quantity of the cut distillates are changed, and then the existing processing technology is integrated, which fails to achieve fundamental technological changes. In addition, these existing combined technologies are more suitable for light crude oil or paraffin-based crude oil. When inferior crude oil such as heavy crude oil or intermediate base crude oil is used as raw material, the yield of high-value products is low. How to find a method or system to convert inferior crude oil into high-value products with high yield is a technical problem that needs to be solved urgently. Summary of the invention

[0006] The present invention provides a method and system for producing high-value products with high crude oil utilization, with the purpose of enabling inferior oil to be well converted into high-value products. Not only is the process flow short, but the yield of high-value products is high and the yield of coke is low, which can significantly reduce carbon emissions from the process.

[0007] In a first aspect, the present invention relates to a method for producing high-value products with high crude oil utilization, the method comprising the following steps:

[0008] (1) subjecting crude oil to distillation and cutting to obtain a light crude oil fraction and a heavy crude oil fraction; wherein the cutting point of the light crude oil fraction and the heavy crude oil fraction is 240-350° C.;

[0009] (2) subjecting the crude oil heavy fraction to extraction and separation to obtain extracted oil of the crude oil heavy fraction and raffinate oil of the crude oil heavy fraction;

[0010] (3) contacting a catalytic cracking feedstock with a catalyst in a catalytic cracking reactor to perform a catalytic cracking reaction, and obtaining cracking gas, cracking light gasoline, cracking heavy gasoline, cracking diesel and cracking heavy oil through oil and gas separation; the catalytic cracking feedstock comprises the light fraction of the crude oil, the extracted oil of the heavy fraction of the crude oil and components that are difficult to convert; wherein the components that are difficult to convert include light hydrocarbons and / or light distillate oil.

[0011] In a second aspect, the present invention relates to a system for producing high-value products with high crude oil utilization, the system comprising a distillation unit, an extraction separation unit and a catalytic cracking unit;

[0012] The distillation unit is provided with a crude oil inlet, a crude oil light fraction outlet pipeline and a crude oil heavy fraction outlet pipeline;

[0013] The crude oil heavy fraction outlet pipeline is connected to the inlet of the material to be separated of the extraction and separation unit, and the extraction and separation unit is also provided with an extraction solvent inlet, an extracted oil outlet of the crude oil heavy fraction and a raffinate oil outlet of the crude oil heavy fraction;

[0014] The catalytic cracking unit is provided with a catalytic cracking feedstock inlet, a cracking gas outlet, a cracking light gasoline outlet, a cracking heavy gasoline outlet, a cracking diesel outlet and a cracking heavy oil outlet;

[0015] The catalytic cracking feed inlet of the catalytic cracking unit is respectively connected to the extracted oil outlet of the crude oil heavy fraction and the crude oil light fraction outlet pipeline;

[0016] The catalytic cracking unit is also provided with an inlet for difficult-to-convert components.

[0017] Beneficial effects:

[0018] 1) Crude oil has strong adaptability. The combination of crude oil component separation and catalytic cracking reaction can convert intermediate base crude oil or lower quality cycloalkane crude oil into high-value products.

[0019] 2) High crude oil utilization rate: Since inferior crude oil contains more difficult-to-cracking components such as polycyclic aromatic hydrocarbons, colloids and asphaltene, which are mainly distributed in the heavy fraction of crude oil, polycyclic aromatic hydrocarbons, colloids and asphaltene in the heavy fraction of crude oil are separated out as raffinate oil to reduce competitive adsorption on the active center of the catalyst, which helps to improve the selectivity of the extracted oil with better cracking performance to generate high-value products and realize efficient utilization of crude oil.

[0020] 3) High yield of high-value products; the raffinate oil rich in polycyclic aromatics or asphaltene in the heavy fraction of crude oil can be used as raw material for needle coke or road asphalt according to its different properties; the extracted oil is converted into light olefins and aromatics as a raw material for catalytic cracking, and the yield of high-value products in the whole process is close to 65% or more.

[0021] 4) The online rate of the device is high: low-quality crude oil has high residual carbon, high metal and high asphaltene content. After component separation, the quality of the catalytic cracking raw material is greatly improved, which not only has a high yield of the target product, but also extends the operation cycle and increases the online rate, thereby effectively improving the economic benefits.

[0022] By adopting the method or system of the present application, low-quality crude oil can be directly and efficiently produced into high-value products such as low-carbon olefins and light aromatics. Not only can high-value chemical raw materials be produced and the deep integration of oil refining and petrochemical industries be promoted, but also the challenges brought about by the shortage of oil resources can be effectively responded to and national energy security can be ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1It is a structural schematic diagram of a specific implementation method of a system for producing high-value products with high crude oil utilization rate of the present invention;

[0024] Description of reference numerals:

[0025] 100 distillation unit 101 crude oil inlet 102 crude oil light fraction outlet pipe

[0026] Wire

[0027] 103 crude oil heavy fraction outlet pipe 200 extraction separation unit 201 extraction solvent inlet

[0028] Wire

[0029] 202 Extraction of heavy fractions of crude oil 203 Extraction of heavy fractions of crude oil 400 Catalytic cracking unit oil export oil export

[0030] 401 cracked gas outlet 402 cracked light gasoline outlet 403 cracked heavy gasoline outlet 404 cracked diesel outlet 405 cracked heavy oil outlet 406 first difficult to convert component inlet

[0031] Port 407 Hydrocracked diesel inlet 408 Second difficult-to-convert component inlet 300 Hydrogenation unit port DETAILED DESCRIPTION

[0032] The present application is further described in detail below through the accompanying drawings and embodiments. Through these descriptions, the characteristics and advantages of the present application will become clearer and more specific.

[0033] The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise noted.

[0034] In addition, the technical features involved in different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0035] Any specific numerical value disclosed herein (including the endpoint of the numerical range) is not limited to the exact value of the numerical value, but should be understood to also cover values ​​close to the exact value, such as all possible numerical values ​​within the range of ±5% of the exact value. In addition, for the disclosed numerical range, the endpoint values ​​of the range, the endpoint values ​​and the specific point values ​​in the range, and the specific point values ​​can be arbitrarily combined to obtain one or more new numerical ranges, and these new numerical ranges should also be regarded as specifically disclosed herein.

[0036] Unless otherwise specified, the terms used herein have the same meaning as commonly understood by those skilled in the art. If a term is defined herein and its definition is different from the commonly understood meaning in the art, the definition herein shall prevail.

[0037] In the present application, the terms "upstream" and "downstream" are based on the flow direction of the reactants. For example, when the reactants flow from bottom to top, "upstream" means the position below, while "downstream" means the position above.

[0038] In a first aspect, the present invention relates to a method for producing high-value products with high crude oil utilization, the method comprising the following steps:

[0039] (1) subjecting crude oil to distillation and cutting to obtain a light crude oil fraction and a heavy crude oil fraction; wherein the cutting point of the light crude oil fraction and the heavy crude oil fraction is 240-350° C.;

[0040] (2) subjecting the crude oil heavy fraction to extraction and separation to obtain extracted oil of the crude oil heavy fraction and raffinate oil of the crude oil heavy fraction;

[0041] (3) contacting a catalytic cracking feedstock with a catalyst in a catalytic cracking reactor to perform a catalytic cracking reaction, and obtaining cracking gas, cracking light gasoline, cracking heavy gasoline, cracking diesel and cracking heavy oil through oil and gas separation; the catalytic cracking feedstock comprises the light fraction of the crude oil, the extracted oil of the heavy fraction of the crude oil and components that are difficult to convert; wherein the components that are difficult to convert include light hydrocarbons and / or light distillate oil.

[0042] It should be noted that in step (1), crude oil is distilled and separated into light crude oil fractions and heavy crude oil fractions according to the difference in boiling points; in step (2), the heavy crude oil fraction is separated by extraction to obtain an extracted oil rich in saturated hydrocarbons and a raffinate oil rich in aromatic hydrocarbons; in step (3), the catalytic cracking raw material undergoes a catalytic cracking reaction under the action of a high temperature and a catalyst, and high-value products such as light olefins and light aromatic hydrocarbons can be obtained through steps such as oil agent separation and oil-gas separation. According to the present application, the method for separating the reaction products to obtain cracking gas, cracking light gasoline, cracking heavy gasoline, cracking diesel and cracking heavy oil can be a conventional method in the art or a method well known to those skilled in the art.

[0043] The method of the present application first cuts the crude oil into light and heavy fractions, and then separates the raffinate oil rich in polycyclic aromatic hydrocarbons, colloids and asphaltenes through extraction and separation, thereby reducing competitive adsorption on the active centers of the catalyst, helping to improve the selectivity of the extracted oil with better cracking performance to better generate high-value products, thereby achieving efficient utilization of crude oil, and the catalytic cracking raw material also introduces the above-mentioned difficult-to-convert components, effectively improving the yield of high-value products.

[0044] According to a specific embodiment of the method described in the first aspect of the present invention, the cracked gas from step (3) is subjected to gas separation to obtain ethylene, propylene, C4 components and other products;

[0045] Wherein, the light hydrocarbons of the difficult-to-convert components include the C4 components;

[0046] The light distillate oil of the difficult-to-convert components includes light distillate oil with a final boiling point of less than 280-350° C., and the light distillate oil of the difficult-to-convert components preferably includes the cracking light gasoline obtained from step (3).

[0047] It should be noted that, as a preferred embodiment, the difficult-to-convert component as part of the catalytic cracking raw material in step (3) includes C4 components obtained from gas separation and cracked light gasoline obtained from oil-gas separation. At this time, the composition of the catalytic cracking raw material can be C4 components, cracked light gasoline, extracted oil of crude oil light fractions and crude oil heavy fractions. In the process of the present application, the catalytic cracking raw material in this case is conducive to further improving the yield of the target product, i.e., the high-value product. In addition, the method for gas separation of cracked gas to obtain ethylene, propylene, C4 components and other products can adopt conventional methods in the art or methods well known to those skilled in the art.

[0048] According to a preferred implementation manner of the method according to the first aspect of the present invention, the method further comprises the following steps:

[0049] The pyrolysis diesel from step (3) is subjected to hydrogenation treatment to obtain hydro-pyrolysis diesel;

[0050] The catalytic cracking feedstock in step (3) also includes the hydrocracking diesel.

[0051] It should be noted that, in this preferred embodiment, the cracked diesel obtained in step (3) is subjected to a hydrogenation reaction under the action of hydrogen and a hydroprocessing catalyst, and the obtained hydrocracked diesel can be used as a component for producing high-octane gasoline or a component for producing aromatics, or can be used as a catalytic cracking raw material to carry out the catalytic cracking reaction of step (3) together with the extracted oil of the light fraction of crude oil and the heavy fraction of crude oil. Using the hydrocracked diesel as a part of the catalytic cracking raw material to carry out a catalytic cracking reaction together with other raw materials is conducive to further improving the yield of the target product, i.e., the high-value product.

[0052] It should be noted that the cracked diesel is contacted with a hydroprocessing catalyst in the presence of hydrogen to carry out a hydroprocessing reaction. The hydroprocessing reaction conditions may be: a hydrogen partial pressure of 4-25 MPa, a reaction temperature of 330-460°C, and a volume space velocity of 0.1-10 hours. -1 , Hydrogen oil volume ratio 300-2000Nm 3 / m 3Preferably, the hydrogen partial pressure is 7-15 MPa, the reaction temperature is 350-400°C, and the volume space velocity is 1-6 hours. -1 、Hydrogen oil volume ratio 500-1400Nm 3 / m 3 .

[0053] It should be noted that, in one embodiment, the active metal component of the hydrogenation catalyst is selected from the metals of Group VIB and / or the non-precious metals of Group VIII, and the carrier is selected from any one or more of alumina, silicon dioxide, and amorphous silicon aluminum. The metal of Group VIB is molybdenum and / or tungsten, and the non-precious metal of Group VIII is nickel and / or cobalt. The active metal component is preferably a combination of one or more of nickel-tungsten, nickel-tungsten-cobalt, nickel-molybdenum or cobalt-molybdenum; preferably, in the hydroprocessing catalyst, the content of nickel and / or cobalt calculated as oxide is 1-25% by weight, and the content of molybdenum and / or tungsten calculated as oxide is 3-35% by weight, based on the total weight of the hydroprocessing catalyst.

[0054] According to a preferred embodiment of the method described in the first aspect of the present invention, the C4 component, the light fraction of crude oil, the cracked light gasoline, the extracted oil of the heavy fraction of crude oil and the hydrocracking diesel are introduced into the catalytic cracking reactor independently and at different positions in the catalytic cracking reactor; preferably, feed ports for the C4 component, the light fraction of crude oil, the cracked light gasoline, the extracted oil of the heavy fraction of crude oil and the hydrocracking diesel are sequentially arranged from upstream to downstream of the catalytic cracking reactor; and / or,

[0055] The weight proportions of the C4 component and the cracked light gasoline as the difficult-to-convert component in the catalytic cracking feedstock are independently 5-20%;

[0056] The weight proportion of the hydrocracking diesel in the catalytic cracking feedstock is 5-30%.

[0057] It should be noted that, in this embodiment, the composition of the catalytic cracking feedstock can be C4 components, light fractions of crude oil, cracked light gasoline, extracted oil of heavy fractions of crude oil and hydrocracking diesel. The catalytic cracking feedstock in this case is fed in the above-mentioned feeding order, or the feed ports of the above-mentioned catalytic cracking feedstocks are arranged in sequence from upstream to downstream, and then the catalytic cracking reaction is carried out, which is conducive to further improving the yield of the target product, i.e., the high-value product. As a further more preferred embodiment, while controlling the feeding order or position as above, the weight proportion of the C4 components and cracked light gasoline in the catalytic cracking feedstock, and / or the weight proportion of the hydrocracking diesel in the catalytic cracking feedstock is controlled as above, which can further improve the yield of the target product, i.e., the high-value product.

[0058] According to another preferred embodiment of the method according to the first aspect of the present invention, the catalytic cracking feedstock in step (3) further comprises the cracking diesel;

[0059] The C4 component, the light fraction of crude oil, the cracked light gasoline, the extracted oil of the heavy fraction of crude oil and the cracked diesel are introduced into the catalytic cracking reactor independently and at different positions in the catalytic cracking reactor; preferably, feed ports for the C4 component, the light fraction of crude oil, the cracked light gasoline, the extracted oil of the heavy fraction of crude oil and the cracked diesel are sequentially arranged from upstream to downstream of the catalytic cracking reactor; and / or,

[0060] The weight proportions of the C4 component and the cracked light gasoline as the difficult-to-convert component in the catalytic cracking feedstock are independently 5-20%;

[0061] The weight proportion of the pyrolysis diesel in the catalytic pyrolysis feedstock is 5-30%.

[0062] It should be noted that, in this preferred embodiment, the composition of the catalytic cracking feedstock can be C4 components, light fractions of crude oil, cracked light gasoline, extracted oil of heavy fractions of crude oil and cracked diesel. The catalytic cracking feedstock in this case is fed in the above-mentioned feeding order, or the feed ports of the above-mentioned catalytic cracking feedstocks are arranged in sequence from upstream to downstream, and then the catalytic cracking reaction is carried out, which is beneficial to further improve the yield of the target product, i.e., the high-value product. As a further more preferred embodiment, while controlling the feeding order or position as above, the weight proportion of the C4 components and cracked light gasoline in the catalytic cracking feedstock, and / or the weight proportion of the cracked diesel in the catalytic cracking feedstock is controlled as above, which can further improve the yield of the target product, i.e., the high-value product.

[0063] According to a specific implementation of the method described in the first aspect of the present invention, in step (1),

[0064] The crude oil is selected from one or more of paraffinic crude oil, paraffinic-intermediate crude oil, intermediate-paraffinic crude oil and intermediate crude oil; and / or,

[0065] The crude oil meets at least one of the following indicators:

[0066] The density at 20℃ is 835-935 kg / m 3 , API gravity greater than 28, UOP K value not less than 11.5, metal content greater than 30 mg / kg. One, two, three or four of the above indicators can be met.

[0067] It should be noted that the method of the present invention has strong adaptability to raw materials, high yield of high-value products, short process flow, and can significantly reduce carbon emissions. Any of the first key component and the second key component of the paraffin-based crude oil belongs to the paraffin-based attribute; the first key component of the paraffin-intermediate base crude oil is the paraffin-based attribute and the second key component is the intermediate-based attribute; the first key component of the intermediate-paraffin-based crude oil is the intermediate-based attribute and the second key component is the paraffin-based attribute; any of the first key component and the second key component of the intermediate-based crude oil belongs to the intermediate-based attribute. The cutting point of the light crude oil fraction and the heavy crude oil fraction can also be 250°C, 260°C, 270°C, 280°C, 290°C, 300°C, 310°C, 320°C, 330°C, 340°C, etc.

[0068] The method of the present application can not only prepare high-value products with high yield from ordinary crude oil, but also prepare high-value products with high yield from inferior crude oil such as the above-mentioned intermediate base crude oil, thus developing a better conversion process for inferior crude oil.

[0069] According to a specific implementation of the method described in the first aspect of the present invention, in step (2),

[0070] The yield of the extracted oil of the heavy fraction of crude oil is greater than 50% by weight, preferably greater than 65% by weight; and / or,

[0071] The content of saturated components in the extracted oil of the heavy fraction of crude oil is greater than 45% by weight, preferably greater than 50% by weight; and / or,

[0072] The heavy metal removal rate of the extracted oil of the heavy fraction of crude oil is greater than 80% by weight, preferably greater than 90% by weight; and / or,

[0073] The asphaltene removal rate of the extracted oil of the crude oil heavy fraction is greater than 90%, preferably greater than 95%.

[0074] It should be noted that by controlling the yield, saturated content, metal removal rate and asphaltene removal rate of the extracted oil of the heavy crude oil fraction as above, the extracted oil of the heavy crude oil fraction is subjected to the catalytic cracking reaction of step (3) together with other catalytic cracking raw materials such as the light crude oil fraction, which is beneficial to further improve the yield of high-value products.

[0075] According to a specific embodiment of the method according to the first aspect of the present invention, in step (3), the light hydrocarbons of the difficult-to-convert components include gaseous hydrocarbons rich in C4 fractions produced by other devices or processes, and the light hydrocarbons of the difficult-to-convert components preferably include C4 fractions produced by other devices or processes;

[0076] The light distillate oil of the difficult-to-convert component is selected from one or more of the following oil products:

[0077] Other primary units include straight-run naphtha, straight-run kerosene, straight-run diesel, secondary processed top oil, raffinate oil, hydrocracked light naphtha, pentane oil, coker gasoline, Fischer-Tropsch synthetic oil, catalytic cracking light gasoline, hydrogenated gasoline and hydrogenated diesel.

[0078] It should be noted that, in one embodiment, the light hydrocarbon in the difficult-to-convert component is a C4 component, which refers to a low molecular hydrocarbon compound that exists in the form of gas at room temperature and pressure and has a C4 fraction as the main component, including alkanes, olefins and alkynes with 4 carbon atoms in the molecule. It includes a gaseous hydrocarbon product rich in C4 fraction produced by the process of the present invention, and may also include gaseous hydrocarbons rich in C4 fraction produced by other processes or device processes, among which the C4 fraction produced by the process of the present invention is 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 preferably above 70% by weight.

[0079] In one embodiment, the light distillate oil in the difficult-to-convert components is a light distillate oil with a final distillation point of less than 280-350°C, including the light distillate oil with a final distillation point of less than 280-350°C produced by the process of the present invention, and may also include a mixture of one or more of primary processed straight-run naphtha, straight-run kerosene, and straight-run diesel; a mixed oil of one or more of secondary processed top oil, raffinate oil, hydrocracking light naphtha, pentane oil, coker gasoline, Fischer-Tropsch synthetic oil, catalytic cracking light gasoline, hydrogenated gasoline, and hydrogenated diesel.

[0080] According to a specific implementation of the method described in the first aspect of the present invention, in step (2),

[0081] The extraction separation is supercritical extraction separation, and the extraction solvent used is selected from low carbon alkanes, and the low carbon alkanes are selected from one or a mixture of ethane, propane, n-butane, isobutane, n-pentane, isopentane, hexane, heptane and octane; and / or,

[0082] The conditions for the extraction separation include: a temperature of 50-100° C., a pressure of 6-20 MPa, and a weight ratio of the extraction solvent to the heavy fraction of crude oil of (2-5):1.

[0083] It should be noted that by controlling the conditions for extraction and separation in step (2) as above, the extracted oil of the heavy fraction of crude oil obtained is used together with components such as the light fraction of crude oil as a catalytic cracking raw material for catalytic cracking in step (3), which enables the catalytic cracking raw material to better undergo catalytic cracking reaction, thereby increasing the yield of high-value products.

[0084] According to a specific embodiment of the method according to the first aspect of the present invention, in step (3), the conditions of the catalytic cracking reaction include:

[0085] The catalytic cracking raw material is mixed with water vapor and then fed into the reaction, the reaction temperature is 510-650° C., the reaction time is 1-20 seconds, the weight ratio of the catalyst to the catalytic cracking raw material is (3-50):1, and the weight ratio of the water vapor to the catalytic cracking raw material is (0.03-0.8):1;

[0086] In step (3), the conditions for the catalytic cracking reaction preferably include:

[0087] The catalytic cracking raw material is mixed with water vapor and then fed into the reaction, the reaction temperature is 550-620° C., the reaction time is 2-10 seconds, the weight ratio of the catalyst to the catalytic cracking raw material is (10-30):1, and the weight ratio of the water vapor to the catalytic cracking raw material is (0.10-0.5):1.

[0088] It should be noted that the reaction temperature can also be 520°C, 530°C, 540°C, 560°C, 570°C, 580°C, 590°C, 600°C, 610°C, 630°C, 640°C, etc. In the method of the present application, by controlling the conditions of catalytic cracking in step (3) as above, the catalytic cracking feedstock can be converted into more high-value products.

[0089] According to a specific embodiment of the method according to the first aspect of the present invention, the catalyst in step (3) comprises the following components, based on the dry weight of the components and the catalyst:

[0090] 1-50 wt% zeolite, 5-99 wt% inorganic oxide, and 0-70 wt% clay;

[0091] Preferably 5-45 wt% zeolite, 10-80 wt% inorganic oxide, and 5-60 wt% clay;

[0092] More preferably, 10-40 wt% zeolite, 20-70 wt% inorganic oxide, and 10-50 wt% clay; and / or,

[0093] The method further comprises the steps of:

[0094] The raffinate from the crude oil heavy fraction in step (2) is used as a raw material for producing needle coke and / or road asphalt.

[0095] It should be noted that, in one embodiment, the zeolite includes a medium-pore zeolite and an optional large-pore zeolite, wherein the medium-pore zeolite is selected from ZSM series zeolites, ZRP zeolites, and any combination thereof; the large-pore zeolite is selected from rare earth Y-type zeolite, rare earth hydrogen Y-type zeolite, ultrastable Y-type zeolite and high-silicon Y-type zeolite, and any combination thereof.

[0096] In one embodiment, the medium pore zeolite accounts for 10-90 wt %, preferably 50-80 wt %, of the total weight of the zeolite on a dry basis.

[0097] In the present application, the medium-pore zeolite and large-pore zeolite follow the conventional definition in the art, that is, the average pore diameter of the medium-pore zeolite is about 0.5-0.6 nm, and the average pore diameter of the large-pore zeolite is about 0.7-1.0 nm.

[0098] As an example, the large-pore zeolite can 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 silicon Y type zeolite. The medium-pore zeolite can be selected from zeolites with MFI structure, such as ZSM series zeolites and / or ZRP zeolites. Optionally, the above-mentioned medium-pore zeolites can also 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 U.S. Patent No. 5,232,675A. 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 of similar structure. A more detailed description of ZSM-5 can be found in U.S. Patent No. 3,702,886A.

[0099] According to the present application, the inorganic oxide is used as a binder, preferably silicon dioxide (SiO 2 ) and / or aluminum oxide (Al 2 O 3 The clay used as the matrix (ie, carrier) is preferably kaolin and / or halloysite.

[0100] In a second aspect, the present invention relates to a system for producing high-value products with high crude oil utilization, such as Figure 1 As shown, the system includes a distillation unit 100, an extraction separation unit 200, and a catalytic cracking unit 400;

[0101] The distillation unit 100 is provided with a crude oil inlet 101, a crude oil light fraction outlet pipeline 102 and a crude oil heavy fraction outlet pipeline 103;

[0102] The crude oil heavy fraction outlet pipeline 103 is connected to the inlet of the material to be separated of the extraction separation unit 200, and the extraction separation unit 200 is also provided with an extraction solvent inlet 201, an extracted oil outlet 202 of the crude oil heavy fraction and a raffinate oil outlet 203 of the crude oil heavy fraction;

[0103] The catalytic cracking unit 400 is provided with a catalytic cracking feedstock inlet, a cracking gas outlet 401, a cracking light gasoline outlet 402, a cracking heavy gasoline outlet 403, a cracking diesel outlet 404 and a cracking heavy oil outlet 405;

[0104] The catalytic cracking feed inlet of the catalytic cracking unit 400 is respectively connected to the extracted oil outlet 202 of the crude oil heavy fraction and the crude oil light fraction outlet pipeline 102;

[0105] The catalytic cracking unit 400 is also provided with an inlet for difficult-to-convert components.

[0106] It should be noted that the crude oil enters the distillation unit 100 through the crude oil inlet 101 for distillation and cutting, and the obtained crude oil light fraction and crude oil heavy fraction are respectively output through the crude oil light fraction outlet pipeline 102 and the crude oil heavy fraction outlet pipeline 103. After the crude oil heavy fraction is output, it enters the extraction and separation unit 200 for extraction and separation, and the obtained extracted oil and raffinate oil are respectively output through the extracted oil outlet 202 of the crude oil heavy fraction and the raffinate oil outlet 203 of the crude oil heavy fraction. The extracted oil output from the extraction and separation unit 200 and the crude oil light fraction output from the distillation unit 100 enter the catalytic cracking unit 400, and together with the difficult-to-convert components entering the difficult-to-convert components inlet 406, they are used as catalytic cracking raw materials for catalytic cracking reaction, and after oil agent separation and oil-gas separation, the obtained cracked gas, cracked light gasoline, cracked heavy gasoline, cracked diesel and cracked heavy oil are respectively output from the cracked gas outlet 401, the cracked light gasoline outlet 402, the cracked heavy gasoline outlet 403, the cracked diesel outlet 404 and the cracked heavy oil outlet 405.

[0107] In the system of the present application, an oil separation device and a reaction product separation device may also be provided, which may adopt devices well known to those skilled in the art. For example, the oil separation device may include a cyclone separator, a settler and a stripper, etc., and the reaction product separation device may be a distillation tower, etc.

[0108] It should be noted that the method described in the first aspect of the present invention can be performed based on but 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 performed based on but not limited to the method described in the first aspect of the present invention.

[0109] According to a specific embodiment of the system of the second aspect of the present invention, the system is further provided with a gas separation unit, the cracked gas outlet 401 is connected to the gas inlet to be separated of the gas separation unit, and the gas separation unit is provided with an ethylene outlet, a propylene outlet, a C4 component outlet and other product outlets;

[0110] The C4 component outlet of the gas separation unit is communicated with the difficult-to-convert component inlet of the catalytic cracking unit 400; the cracked light gasoline outlet 402 of the catalytic cracking unit 400 is communicated with the difficult-to-convert component inlet.

[0111] It should be noted that, in this preferred embodiment, the C4 component produced by the gas separation unit and the cracking light gasoline produced by the catalytic cracking unit 400 are used as catalytic cracking raw materials for catalytic cracking reaction together with the extracted oil of the crude oil light fraction and the crude oil heavy fraction. The C4 component and the cracking light gasoline can enter the catalytic cracking unit 400 through the difficult-to-convert component inlet, specifically, they can enter through the same difficult-to-convert component inlet, or they can enter the catalytic cracking unit 400 through different difficult-to-convert component inlets respectively.

[0112] According to a specific embodiment of the system of the second aspect of the present invention, the system further comprises a hydrogenation unit 300, the cracked diesel outlet 404 of the catalytic cracking unit 400 is connected to the hydrogenated material inlet of the hydrogenation unit 300, and the hydrogenation unit 300 is further provided with a hydrocracking diesel outlet;

[0113] Preferably, the catalytic cracking unit 400 is provided with a first difficult-to-convert component inlet 406, a crude oil light fraction inlet, a second difficult-to-convert component inlet 408, an extracted oil inlet and a hydrocracking diesel inlet 407 in sequence from upstream to downstream, the C4 component outlet is connected to the first difficult-to-convert component inlet 406, the crude oil light fraction outlet pipeline 102 is connected to the crude oil light fraction inlet, the cracking light gasoline outlet 402 is connected to the second difficult-to-convert component inlet 408, the extracted oil outlet 202 of the crude oil heavy fraction is connected to the extracted oil inlet, and the hydrocracking diesel outlet is connected to the hydrocracking diesel inlet 407.

[0114] It should be noted that, in this preferred embodiment, the cracked diesel produced by catalytic cracking is output through the cracked diesel outlet 404 and then enters the hydrogenation unit 300 for hydrogenation treatment. The obtained hydrocracking diesel is output through the hydrocracking diesel outlet and then enters the catalytic cracking unit 400 through the hydrocracking diesel inlet 407 as a catalytic cracking feedstock for catalytic cracking reaction. In this embodiment, the above-mentioned several catalytic cracking feedstocks are sequentially introduced into the reactor of the catalytic cracking unit 400 through the above-mentioned different inlets, and the feeding order of the several feedstocks or the upstream and downstream relationship of the feeding positions are cleverly controlled, which is conducive to further improving the yield of the target high-value product.

[0115] According to a specific embodiment of the system of the second aspect of the present invention, the cracked diesel outlet 404 of the catalytic cracking unit 400 is connected to the catalytic cracking feedstock inlet;

[0116] Preferably, the catalytic cracking unit 400 is provided with a first difficult-to-convert component inlet 406, a crude oil light fraction inlet, a second difficult-to-convert component inlet 408, an extracted oil inlet and a cracked diesel inlet in order from upstream to downstream, the C4 component outlet is connected to the first difficult-to-convert component inlet 406, the crude oil light fraction outlet pipeline 102 is connected to the crude oil light fraction inlet, the cracked light gasoline outlet 402 is connected to the second difficult-to-convert component inlet 408, the extracted oil outlet 202 of the crude oil heavy fraction is connected to the extracted oil inlet, and the cracked diesel outlet 404 is connected to the cracked diesel inlet;

[0117] and / or,

[0118] The extraction and separation unit 200 is a supercritical extraction unit; and / or,

[0119] The system further comprises a needle coke production unit and a road asphalt production unit, and the raffinate oil outlet 203 of the crude oil heavy fraction is connected to the raw material inlet of the needle coke production unit and / or the road asphalt production unit.

[0120] It should be noted that, in this preferred embodiment, the cracked diesel produced in the catalytic cracking unit 400 is output through the cracked diesel outlet 404 and then enters the catalytic cracking unit 400 to undergo a catalytic cracking reaction together with other catalytic cracking raw materials. In this preferred embodiment, the above-mentioned several catalytic cracking raw materials are sequentially introduced into the reactor of the catalytic cracking unit 400 from the above-mentioned different inlets, and the feed sequence of the several raw materials or the upstream and downstream relationship of the feed positions are cleverly controlled, which is conducive to further improving the yield of the target high-value product.

[0121] According to a specific embodiment of the system of the second aspect of the present invention, the reactor provided in the catalytic cracking unit 400 is selected from one or a combination of fluidized bed, turbulent bed, fast bed and dilute phase transport bed;

[0122] The reactor is a combination of one, two or more reactors, selected from one or two series combinations of isolinear reactors, isodiameter reactors, variable diameter reactors, upward conveyor line reactors and downward conveyor line reactors.

[0123] It should be noted that the gas velocity in the turbulent bed and fast bed reactors can be 0.1 m / s to 2 m / s, and the gas velocity in the dilute phase transport bed can be 2 m / s to 20 m / s.

[0124] In one embodiment, in order to allow the crude oil to react fully, the catalytic cracking reactor may be provided with one or more reaction zones according to the different catalytic cracking reaction performances of the raw material. The number of the reaction zones may be 2-8, preferably 2-3.

[0125] In one embodiment, the reactor of the catalytic cracking unit may be provided with one or more, for example, one, two or more, inlets for extracting oil from the heavy crude oil fraction. The one or more inlets for extracting oil from the heavy crude oil fraction may be independently provided in the catalytic cracking reactor.

[0126] In one embodiment, the reactor of the catalytic cracking unit may be provided with one or more, for example, one, two or more difficult-to-convert component inlets, and the one or more difficult-to-convert component inlets may be independently provided in the catalytic cracking reactor.

[0127] In one embodiment, the reactor of the catalytic cracking unit may be provided with one or more, for example, one, two or more hydrocracking diesel inlets, and the one or more hydrocracking diesel inlets may be independently provided in the catalytic cracking reactor.

[0128] In one embodiment, the light hydrocarbons and light distillate oil of the difficult-to-convert components can be introduced into the catalytic cracking reactor at the same position of the reactor, or can be introduced into the catalytic cracking reactor at different positions. Preferably, the light hydrocarbons are introduced into the catalytic cracking reactor at one or more positions upstream of the light distillate oil introduction position, which is beneficial to further improve the yield of the target product, i.e., the high-value product.

[0129] Figure 1 A preferred embodiment of the system for producing high-value products with high crude oil utilization rate of the present application is provided.

[0130] like Figure 1 As shown, crude oil enters the distillation unit 100 through the crude oil inlet 101 and is separated into a light crude oil fraction and a heavy crude oil fraction under the action of heat;

[0131] The separated crude oil heavy fraction enters the extraction separation unit 200 through the crude oil heavy fraction outlet pipeline 103, contacts with the extraction solvent from the extraction solvent inlet 201 and separates the components to obtain extracted oil and raffinate oil. The extracted oil flows out through the crude oil heavy fraction extracted oil outlet 202 and is sent to the catalytic cracking unit 400; the raffinate oil flows out through the crude oil heavy fraction extracted oil outlet 203 and is sent out of the device to be used as a raw material for the production of needle coke or road asphalt.

[0132] The light fraction of crude oil from the light fraction outlet pipeline 102 and the extracted oil of the heavy fraction of crude oil from the extracted oil outlet 202 of the heavy fraction of crude oil enter the catalytic cracking unit 400, and a catalytic cracking reaction occurs under the action of heat and a catalytic cracking catalyst. The reaction products are separated to obtain cracking gas (flowing out of the cracking gas outlet 401), cracking light gasoline (flowing out of the cracking light gasoline outlet 402), cracking heavy gasoline (flowing out of the cracking heavy gasoline outlet 403), cracking diesel (flowing out of the cracking diesel outlet 404) and cracking heavy oil (flowing out of the cracking heavy oil outlet 405). The cracking gas is further separated to obtain ethylene, propylene, C4 fraction and other products; the C4 fraction and cracking light gasoline are used as difficult-to-convert components and are returned to the catalytic cracking unit through the difficult-to-convert component inlet for further conversion into high-value products; the cracking diesel flows out of the cracking diesel outlet 404 and is sent to the hydrogenation unit 300, and a hydrogenation refining reaction occurs under the action of hydrogen and a hydrogenation catalyst. The reaction products enter the catalytic cracking unit through the hydrogenation cracking diesel inlet 407 for further catalytic cracking reaction.

[0133] The present invention is further described in detail by way of examples below, but the present invention is not limited thereto. In the following examples, unless otherwise specified, the experimental instruments and raw materials involved are all commercially available products.

[0134] The feedstock oil used in the following examples and comparative examples is Kuwait crude oil, and its properties are shown in Table 1. The catalyst used in the catalytic cracking unit is a commercial catalytic cracking catalyst purchased from the Catalyst Branch of Sinopec, with a trade name of DMMC-2. The trade name of the hydrotreating catalyst is RN-32L.

[0135] In this application, the yield of high-value products refers to the total yield of light olefins (ethylene, propylene, butene), light aromatics (BTX), needle coke or road asphalt components (raffinate from the heavy fraction of crude oil). The yield of products such as ethylene and propylene refers to the weight percentage in crude oil.

[0136] Table 1 Properties of crude oil used

[0137]

[0138]

[0139] Example 1

[0140] use Figure 1 The system shown in the figure performs actual boiling point distillation to separate the Kuwait crude oil in Table 1 into a light crude oil fraction and a heavy crude oil fraction, wherein the cut point between the light crude oil fraction and the heavy crude oil fraction is about 300°C, and the yields of the light crude oil fraction and the heavy crude oil fraction are 34.24% and 65.76%, respectively.

[0141] In the extraction and separation unit, propane is used as a solvent to separate the heavy fraction of crude oil by supercritical extraction to obtain extracted oil and raffinate oil, wherein the yield of extracted oil is 76.2% (the proportion of extracted oil in the heavy fraction of crude oil = 50.11% ÷ 65.76%), the mass fraction of saturated fraction in the extracted oil is 52.4%, the heavy metal removal rate is above 96%, and the asphaltene removal rate is 99%. The obtained raffinate oil can be used as a raw material for road asphalt.

[0142] In the hydrogenation unit, the cracked diesel obtained from the catalytic cracking reaction contacts with a hydroprocessing catalyst to cause a saturation reaction of polycyclic aromatic hydrocarbons, and the resulting hydrogenated product (hydrogenated cracked diesel) is used as feed to the catalytic cracking unit.

[0143] In the catalytic cracking unit, a small fixed fluidized bed reaction device is used to carry out catalytic cracking reaction tests. The raw materials are light fractions of crude oil, extracted oil from heavy fractions of crude oil, C4 components (obtained from gas separation of cracked gas), cracked light gasoline (obtained from catalytic cracking reaction) and hydrocracking diesel. Before the test, the catalyst is first loaded into the reactor, and the reactor is heated to the reaction temperature while the catalyst is kept in a fluidized state. According to the catalytic cracking reaction performance of the raw materials, the order of raw material feeding (from upstream to downstream) is C4 components, light fractions of crude oil, cracked light gasoline, extracted oil from heavy fractions of crude oil and hydrocracking diesel. All raw materials are mixed with high-temperature water vapor after preheating, enter the bottom of the fluidized reactor through the feed nozzle, and react on the hot catalyst. After the reaction, water vapor is introduced for stripping, and the reaction oil and gas enter the multi-stage condensation separation system for separation to obtain cracking gas products and liquid products. The yields of the gas products and liquid products are measured, and the gas products enter the separation system for further separation into C4 components and other gases. After the reaction is completed, the reactor is automatically heated to the regeneration temperature, and oxygen is introduced into the reactor to burn and regenerate the catalyst. The real-time CO 2 The concentration is calculated based on the flue gas flow integral. The gas products are collected and then distributed using offline chromatography. The liquid products are analyzed using simulated distillation chromatography to obtain the mass fractions of pyrolysis gasoline (pyrolysis light gasoline and pyrolysis heavy gasoline), pyrolysis diesel and pyrolysis heavy oil.

[0144] The reaction conditions and product yields of different units are listed in Tables 2 and 3. As can be seen from Table 3, the ethylene yield of this embodiment reaches 12.91% by weight, the propylene yield reaches 24.85% by weight, the light aromatics (BTX) yield reaches 9.70% by weight, the high-value product yield is as high as 67.52%, and the coke yield is 10.35%.

[0145] Example 2

[0146] use Figure 1In the system shown, the operation of the extraction separation unit is the same as that of Example 1. There is no hydrogenation unit, and the cracking diesel produced by the catalytic cracking unit is directly used as the cracking feedstock. The operation steps of the catalytic cracking unit are the same as those of Example 1, and the feed sequence of the raw materials (from upstream to downstream) is C4 components, light fractions of crude oil, cracked light gasoline, extracted oil of heavy fractions of crude oil, and cracked diesel.

[0147] The reaction conditions and product yields of different units are listed in Tables 2 and 3. As can be seen from Table 3, the ethylene yield of this embodiment reaches 12.69% by weight, the propylene yield reaches 24.32% by weight, the light aromatics (BTX) yield reaches 9.55% by weight, the high-value product yield is as high as 66.77%, and the coke yield is 10.42%.

[0148] Comparative Example 1

[0149] There is no crude oil distillation process, and the crude oil directly enters the catalytic cracking unit.

[0150] Using the Kuwait crude oil and DMMC-2 catalyst shown in Table 1, a catalytic cracking reaction test was carried out using a small fixed fluidized bed reactor. Before the test, the catalyst was first loaded into the reactor, and the reactor was heated to the reaction temperature while the catalyst was kept in a fluidized state. The raw materials were mixed with high-temperature water vapor after preheating, and entered the bottom of the fluidized reactor bed through a feed nozzle to react on the hot catalyst. After the reaction, water vapor was introduced for stripping, and the reaction oil and gas entered a multi-stage condensation separation system for separation to obtain cracking gas products and liquid products. The gas products and liquid products were measured to obtain yields. After the reaction was completed, the reactor automatically heated up to the regeneration temperature, and oxygen was introduced into the reactor to regenerate the catalyst to be regenerated by burning. The regenerated flue gas was measured by an infrared analyzer to obtain real-time CO 2 The concentration is calculated based on the flue gas flow integral. The gaseous products are collected and then distributed by offline chromatography. The liquid products are analyzed by simulated distillation chromatography to obtain the mass fractions of pyrolysis gasoline, pyrolysis diesel and pyrolysis heavy oil. The reaction conditions and product distribution are listed in Table 2 and Table 3.

[0151] From the results in Table 3, it can be seen that the ethylene yield of this comparative example is only 5.56% by weight, the propylene yield is only 15.85% by weight, the light aromatics (BTX) yield is 6.34%, the high-value product yield is 39.04%, and the coke yield is as high as 13.12%.

[0152] Comparative Example 2

[0153] The Kuwait crude oil was separated into a light crude oil fraction and a heavy crude oil fraction by using the actual boiling point distillation method shown in Example 1, and then the two fractions were respectively fed into a catalytic cracking reactor.

[0154] A catalytic cracking reaction test was conducted using a small fixed fluidized bed reactor. Before the test, the catalyst was first loaded into the reactor, and the reactor was heated to the reaction temperature while the catalyst was kept in a fluidized state. First, the light fraction of crude oil was mixed with high-temperature water vapor, which entered the bottom of the fluidized reactor through a feed nozzle and reacted on a hot catalyst; then, the preheated heavy fraction of crude oil was mixed with high-temperature water vapor, which entered the bottom of the fluidized reactor through a feed nozzle and reacted on a hot catalyst. After the reaction, water vapor was introduced for stripping, and the reaction oil and gas entered a multi-stage condensation separation system for separation to obtain cracking gas products and liquid products. The yields of both gas products and liquid products were measured. After the reaction, the reactor automatically heated up to the regeneration temperature, and at the same time, oxygen was introduced into the reactor to regenerate the catalyst to be regenerated by charring. The real-time CO 2 The concentration is calculated based on the flue gas flow integral. The gaseous products are collected and then distributed by offline chromatography. The liquid products are analyzed by simulated distillation chromatography to obtain the mass fractions of pyrolysis gasoline, pyrolysis diesel and pyrolysis heavy oil. The reaction conditions and product distribution are listed in Table 2 and Table 3.

[0155] From the results in Table 3, it can be seen that the ethylene yield of this comparative example is only 10.01% by weight, the propylene yield is only 12.81% by weight, the light aromatics (BTX) yield is 8.40%, the high-value product yield is 41.88%, and the coke yield is as high as 12.71%.

[0156] Table 2 Reaction conditions of Examples and Comparative Examples

[0157]

[0158]

[0159] The amount of water vapor used, weight %, represents the proportion of water vapor in the total weight of the catalytic cracking feedstock.

[0160] The weight ratio of catalyst to catalytic cracking feedstock, the proportion of difficult-to-convert components in the catalytic cracking feedstock and the proportion of (hydrogenated) cracked diesel in the catalytic cracking feedstock, the amount of catalytic cracking feedstock does not include difficult-to-convert components (C4 components and cracked light gasoline).

[0161] Table 3 Comparison of reaction results between examples and comparative examples

[0162]

[0163]

[0164] It can be seen from the results of the above embodiments and comparative examples that when the catalytic cracking method and system of the present application are used for catalytic cracking reaction of crude oil, the yields of ethylene and propylene are significantly improved, the yield of high-value products is high, and the yield of coke is reduced, that is, the utilization rate of crude oil atoms is high and the carbon emissions of the process are greatly reduced.

[0165] In the description of the present application, it should be noted that the terms "upper", "lower", "inside", "outside", "front", "back", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships in the working state of the present application. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on the present application.

[0166] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "install", "connect" and "connect" should be understood in a broad sense. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0167] The present application has been described above in conjunction with preferred embodiments, but these embodiments are only exemplary and serve only as an illustration. On this basis, various replacements and improvements may be made to the present application, all of which fall within the scope of protection of the present application.

Claims

1. A method for producing high-value products with high crude oil utilization, characterized in that: The method comprises the following steps: (1) subjecting crude oil to distillation and cutting to obtain a light crude oil fraction and a heavy crude oil fraction; wherein the cutting point of the light crude oil fraction and the heavy crude oil fraction is 240-350° C.; (2) subjecting the crude oil heavy fraction to extraction and separation to obtain extracted oil of the crude oil heavy fraction and raffinate oil of the crude oil heavy fraction; (3) contacting a catalytic cracking feedstock with a catalyst in a catalytic cracking reactor to perform a catalytic cracking reaction, and obtaining cracking gas, cracking light gasoline, cracking heavy gasoline, cracking diesel and cracking heavy oil through oil and gas separation; the catalytic cracking feedstock comprises the light fraction of the crude oil, the extracted oil of the heavy fraction of the crude oil and components that are difficult to convert; wherein the components that are difficult to convert include light hydrocarbons and / or light distillate oil.

2. The method according to claim 1, characterized in that: The cracked gas from step (3) is subjected to gas separation to obtain ethylene, propylene, C4 components and other products; Wherein, the light hydrocarbons of the difficult-to-convert components include the C4 components; The light distillate oil of the difficult-to-convert components includes light distillate oil with a final boiling point of less than 280-350° C., and the light distillate oil of the difficult-to-convert components preferably includes the cracking light gasoline obtained from step (3).

3. The method according to claim 2, characterized in that The method further comprises the steps of: The pyrolysis diesel from step (3) is subjected to hydrogenation treatment to obtain hydro-pyrolysis diesel; The catalytic cracking feedstock in step (3) also includes the hydrocracking diesel.

4. The method according to claim 3, characterized in that The C4 component, the light fraction of crude oil, the cracked light gasoline, the extracted oil of the heavy fraction of crude oil and the hydrocracking diesel are introduced into the catalytic cracking reactor independently and at different positions in the catalytic cracking reactor; preferably, feed ports for the C4 component, the light fraction of crude oil, the cracked light gasoline, the extracted oil of the heavy fraction of crude oil and the hydrocracking diesel are sequentially arranged from upstream to downstream of the catalytic cracking reactor; and / or, The weight proportions of the C4 component and the cracked light gasoline as the difficult-to-convert component in the catalytic cracking feedstock are independently 5-20%; The weight proportion of the hydrocracking diesel in the catalytic cracking feedstock is 5-30%.

5. The method according to claim 2, characterized in that: The catalytic cracking feedstock in step (3) also includes the cracked diesel; The C4 component, the light fraction of crude oil, the cracked light gasoline, the extracted oil of the heavy fraction of crude oil and the cracked diesel are introduced into the catalytic cracking reactor independently and at different positions in the catalytic cracking reactor; preferably, feed ports for the C4 component, the light fraction of crude oil, the cracked light gasoline, the extracted oil of the heavy fraction of crude oil and the cracked diesel are sequentially arranged from upstream to downstream of the catalytic cracking reactor; and / or, The weight proportions of the C4 component and the cracked light gasoline as the difficult-to-convert component in the catalytic cracking feedstock are independently 5-20%; The weight proportion of the pyrolysis diesel in the catalytic pyrolysis feedstock is 5-30%.

6. The method according to claim 1, characterized in that In step (1), The crude oil is selected from one or more of paraffinic crude oil, paraffinic-intermediate crude oil, intermediate-paraffinic crude oil and intermediate crude oil; and / or, The crude oil meets at least one of the following indicators: The density at 20℃ is 835-935 kg / m 3 , API gravity greater than 28, UOP K value not less than 11.5, and metal content greater than 30 mg / kg.

7. The method according to claim 1, characterized in that In step (2), The yield of the extracted oil of the heavy fraction of crude oil is greater than 50% by weight, preferably greater than 65% by weight; and / or, The content of saturated components in the extracted oil of the heavy fraction of crude oil is greater than 45% by weight, preferably greater than 50% by weight; and / or, The heavy metal removal rate of the extracted oil of the heavy fraction of crude oil is greater than 80% by weight, preferably greater than 90% by weight; and / or, The asphaltene removal rate of the extracted oil of the crude oil heavy fraction is greater than 90%, preferably greater than 95%.

8. The method according to claim 1, characterized in that In step (3), the light hydrocarbons of the difficult-to-convert components include gaseous hydrocarbons rich in C4 fractions produced by other devices or processes, and the light hydrocarbons of the difficult-to-convert components preferably include C4 fractions produced by other devices or processes; The light distillate oil of the difficult-to-convert component is selected from one or more of the following oil products: Other primary units include straight-run naphtha, straight-run kerosene, straight-run diesel, secondary processed top oil, raffinate oil, hydrocracked light naphtha, pentane oil, coker gasoline, Fischer-Tropsch synthetic oil, catalytic cracking light gasoline, hydrogenated gasoline and hydrogenated diesel.

9. The method according to claim 1, characterized in that: In step (2), The extraction separation is supercritical extraction separation, and the extraction solvent used is selected from low carbon alkanes, and the low carbon alkanes are selected from one or a mixture of ethane, propane, n-butane, isobutane, n-pentane, isopentane, hexane, heptane and octane; and / or, The conditions for the extraction separation include: a temperature of 50-100° C., a pressure of 6-20 MPa, and a weight ratio of the extraction solvent to the heavy fraction of crude oil of (2-5):

1.

10. The method according to any one of claims 1 to 5, characterized in that: In step (3), the conditions for the catalytic cracking reaction include: The catalytic cracking raw material is mixed with water vapor and then fed into the reaction, the reaction temperature is 510-650° C., the reaction time is 1-20 seconds, the weight ratio of the catalyst to the catalytic cracking raw material is (3-50):1, and the weight ratio of the water vapor to the catalytic cracking raw material is (0.03-0.8):1; In step (3), the conditions for the catalytic cracking reaction preferably include: The catalytic cracking raw material is mixed with water vapor and then fed into the reaction, the reaction temperature is 550-620° C., the reaction time is 2-10 seconds, the weight ratio of the catalyst to the catalytic cracking raw material is (10-30):1, and the weight ratio of the water vapor to the catalytic cracking raw material is (0.10-0.5):

1.

11. The method according to claim 1, characterized in that: The catalyst in step (3) comprises the following components, based on the dry weight of the components and the catalyst: 1-50 wt% zeolite, 5-99 wt% inorganic oxide, and 0-70 wt% clay; Preferably 5-45 wt% zeolite, 10-80 wt% inorganic oxide, and 5-60 wt% clay; More preferably, 10-40 wt% zeolite, 20-70 wt% inorganic oxide, and 10-50 wt% clay; and / or, The method further comprises the steps of: The raffinate from the crude oil heavy fraction in step (2) is used as a raw material for producing needle coke and / or road asphalt.

12. A system for producing high-value products with high crude oil utilization, characterized in that: The system comprises a distillation unit (100), an extraction separation unit (200) and a catalytic cracking unit (400); The distillation unit (100) is provided with a crude oil inlet (101), a crude oil light fraction outlet pipeline (102) and a crude oil heavy fraction outlet pipeline (103); The crude oil heavy fraction outlet pipeline (103) is in communication with the inlet of the material to be separated of the extraction and separation unit (200), and the extraction and separation unit (200) is further provided with an extraction solvent inlet (201), an extracted oil outlet (202) of the crude oil heavy fraction, and a raffinate oil outlet (203) of the crude oil heavy fraction; The catalytic cracking unit (400) is provided with a catalytic cracking feedstock inlet, a cracking gas outlet (401), a cracking light gasoline outlet (402), a cracking heavy gasoline outlet (403), a cracking diesel outlet (404) and a cracking heavy oil outlet (405); The catalytic cracking raw material inlet of the catalytic cracking unit (400) is respectively connected to the extracted oil outlet (202) of the crude oil heavy fraction and the crude oil light fraction outlet pipeline (102); The catalytic cracking unit (400) is also provided with an inlet for difficult-to-convert components.

13. The system according to claim 12, characterized in that The system is also provided with a gas separation unit, the cracked gas outlet (401) is connected to the inlet of the gas to be separated of the gas separation unit, and the gas separation unit is provided with an ethylene outlet, a propylene outlet, a C4 component outlet and other product outlets; The C4 component outlet of the gas separation unit is connected to the difficult-to-convert component inlet of the catalytic cracking unit (400); the cracked light gasoline outlet (402) of the catalytic cracking unit (400) is connected to the difficult-to-convert component inlet.

14. The system according to claim 13, characterized in that The system further comprises a hydrogenation unit (300), the cracked diesel outlet (404) of the catalytic cracking unit (400) is connected to the hydrogenated material inlet of the hydrogenation unit (300), and the hydrogenation unit (300) is also provided with a hydrocracking diesel outlet; Preferably, the catalytic cracking unit (400) is provided with a first difficult-to-convert component inlet (406), a crude oil light fraction inlet, a second difficult-to-convert component inlet (408), an extracted oil inlet and a hydrocracking diesel inlet (407) in sequence from upstream to downstream, the C4 component outlet is connected to the first difficult-to-convert component inlet (406), the crude oil light fraction outlet pipeline (102) is connected to the crude oil light fraction inlet, the cracking light gasoline outlet (402) is connected to the second difficult-to-convert component inlet (408), the extracted oil outlet (202) of the crude oil heavy fraction is connected to the extracted oil inlet, and the hydrocracking diesel outlet is connected to the hydrocracking diesel inlet (407).

15. The system according to claim 13, characterized in that The cracked diesel outlet (404) of the catalytic cracking unit (400) is connected to the catalytic cracking feedstock inlet; Preferably, the catalytic cracking unit (400) is provided with a first difficult-to-convert component inlet (406), a crude oil light fraction inlet, a second difficult-to-convert component inlet (408), an extracted oil inlet and a cracked diesel inlet in order from upstream to downstream, the C4 component outlet is connected to the first difficult-to-convert component inlet (406), the crude oil light fraction outlet pipeline (102) is connected to the crude oil light fraction inlet, the cracked light gasoline outlet (402) is connected to the second difficult-to-convert component inlet (408), the crude oil heavy fraction extracted oil outlet (202) is connected to the extracted oil inlet, and the cracked diesel outlet (404) is connected to the cracked diesel inlet; and / or, The extraction and separation unit (200) is a supercritical extraction unit; and / or, The system further comprises a needle coke production unit and a road asphalt production unit, and the raffinate oil outlet (203) of the crude oil heavy fraction is connected to the raw material inlet of the needle coke production unit and / or the road asphalt production unit.

16. The system according to claim 12, characterized in that The reactor provided in the catalytic cracking unit (400) is selected from one or a combination of fluidized bed, turbulent bed, fast bed and dilute phase transport bed; The reactor is a combination of one, two or more reactors, selected from one or two series combinations of isolinear reactors, isodiameter reactors, variable diameter reactors, upward conveyor line reactors and downward conveyor line reactors.

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