System and method for producing chemical raw materials using crude oil

Abstract

The present invention relates to a system and method for producing chemical raw materials from crude oil. The system includes an impurity removal subsystem, a classification processing subsystem, and a product refining subsystem. The present invention efficiently removes impurity components from crude oil by directly reacting molten alkali metal with impurities, making it suitable for use in more active conversion reaction systems, thereby reducing the phase change separation process of repeated distillation, reducing overall energy consumption, and improving processing efficiency. In addition, the three subsystems of this method organically combine the cracking of light oil and the cracking of heavy oil, achieving efficient utilization of crude oil, and can process crude oil to produce olefins and aromatics at a lower processing cost.

Description

Technical Field

[0001] The present invention relates to a system and method for producing chemical raw materials by utilizing crude oil, belonging to the technical field of chemical industry. Background Art

[0002] As refining capacity increases, the growth in demand for refined oil products slows, while demand for chemical products remains substantial. The need for traditional fuel-based refineries to transform and upgrade to integrated refining and chemical plants is urgent. Therefore, developing a system and method for producing chemical raw materials at low cost and with high material utilization is of great practical significance.

[0003] In traditional refinery production, distillation typically begins in a primary processing unit, the atmospheric and vacuum unit. Different fractions are then processed separately in secondary processing units. This often involves complex processes, where primary processed products like gaseous hydrocarbons and distillate oils are hydrotreated to convert them into the primary feedstock for olefin and aromatic products. However, atmospheric and vacuum units are large and consume the most energy, typically exceeding 20% ​​of the total energy consumption of the entire enterprise. The lengthy secondary processing process increases production costs. The sulfur and nitrogen impurities primarily removed by hydroprocessing generate hydrogen sulfide and ammonia, which are not only unusable but also require further processing to generate sulfides and nitrides to prevent atmospheric pollution. Consequently, existing technologies suffer from lengthy process flows and high production costs.

[0004] Patent CN 109575982 A provides a method for producing light olefins and aromatics through catalytic cracking of crude oil. This method involves distilling crude oil into light and heavy components, which are then catalytically cracked to produce these components. While this invention can convert crude oil into ethylene, propylene, and aromatics all at once, the process relies on a single device, and some materials are not suitable for catalytic cracking. For example, aromatics are prone to coking during cracking, which reduces crude oil utilization.

[0005] Patent CN 110540868 A provides a low-cost system for producing ethylene through oil cracking. This system uses simple pretreatment on broad-fraction crude oil. Under the action of superheated steam, the gaseous fraction, liquid light fraction, and liquid heavy fraction are thermally cracked to produce products and byproducts such as pyrolysis gasoline and pyrolysis fuel oil. This method has a short flow, simple process, and low cost. However, the pretreatment does not adequately remove impurities, and the single thermal cracking process cannot efficiently convert the aromatic components in the crude oil into the target products, reducing crude oil utilization.

[0006] Patent CN 112694382 A provides a method and system for producing light olefins from crude oil. This method utilizes two or more vaporizers in alternating operation to ensure online coke removal and extend the unit's online rate. This overcomes the existing issues of insufficient crude oil vaporization and the tendency for coking during the cracking process. However, this system lacks an impurity removal process, which compromises the quality of the light olefin products.

[0007] Patent CN 111196936 A provides a combined processing method for directly producing olefins from crude oil. This method offers a short process flow and low energy consumption, but inadequate demetallization, desulfurization, and denitrogenation of the crude oil results in increased energy consumption during cracking of the upgraded oil. Furthermore, this method does not further process heavy naphtha and kerosene during the olefin production process, failing to maximize olefin production and chemical feedstock efficiency. Summary of the Invention

[0008] To address at least one of the aforementioned technical problems, the present invention provides a system and method for producing chemical raw materials from crude oil. This method efficiently removes impurities from crude oil by directly reacting molten alkali metal with impurities, making it suitable for use in more active conversion reaction systems. This reduces the need for repeated distillation phase change separation processes, reduces overall energy consumption, and improves processing efficiency. Furthermore, the three subsystems of the present invention organically combine light oil cracking and heavy oil cracking, achieving efficient utilization of the crude oil. This allows crude oil to be processed to produce olefins and aromatics at a lower cost.

[0009] The present invention first provides a system for producing chemical raw materials from crude oil, comprising: an impurity removal subsystem, a classification processing subsystem, and a product refining subsystem;

[0010] The impurity removal subsystem includes a pretreatment device, a sodium desulfurization device, an alkali neutralization device, a sodium-sulfur electrolytic cell, a lithium denitrification device, and a lithium-nitrogen electrolytic cell; the outlet of the pretreatment device is connected to the inlet of the sodium desulfurization device; the outlet of the sodium desulfurization device is connected to the inlet of the lithium denitrification device, the inlet of the alkali neutralization device, and the inlet of the sodium-sulfur electrolytic cell; the outlet of the alkali neutralization device is connected to the inlet of the sodium-sulfur electrolytic cell; the outlet of the sodium-sulfur electrolytic cell is connected to the inlet of the sodium desulfurization device to recycle metallic sodium; the outlet of the lithium denitrification device is connected to the inlet of the lithium-nitrogen electrolytic cell; the outlet of the lithium denitrification device produces decontaminated and upgraded oil; the outlet of the lithium-nitrogen electrolytic cell is connected to the inlet of the lithium denitrification device to recycle metallic lithium;

[0011] The classification processing subsystem includes a flash tank, a light hydrocarbon recovery unit, a catalytic reforming unit, and an ebullated bed hydrocracking unit; the outlet of the lithium denitrification unit in the impurity removal subsystem is connected to the inlet of the flash tank of the classification processing subsystem; the outlet of the flash tank is connected to the inlet of the light hydrocarbon recovery unit and the inlet of the ebullated bed hydrocracking unit;

[0012] The product refining subsystem includes an aromatics extraction unit, an ethylene cracking unit, a hydrocracking unit, a pyrolysis gasoline hydrogenation unit, and a heating furnace; the outlet of the light hydrocarbon recovery unit is connected to the inlet of the catalytic reforming unit and the inlet of the ethylene cracking unit; the outlet of the catalytic reforming unit is connected to the inlet of the ethylene cracking unit and the inlet of the aromatics extraction unit; the outlet of the ebullated bed hydrocracking unit is connected to the inlet of the ethylene cracking unit, the inlet of the catalytic reforming unit, the inlet of the hydrocracking unit, and the inlet of the heating furnace; the outlet of the aromatics extraction unit is connected to the inlet of the ethylene cracking unit and the inlet of the hydrocracking unit; the outlet of the hydrocracking unit is connected to the inlet of the ethylene cracking unit and the inlet of the catalytic reforming unit; the outlet of the ethylene cracking unit is connected to the inlet of the pyrolysis gasoline hydrogenation unit and the inlet of the heating furnace; the outlet of the pyrolysis gasoline hydrogenation unit is connected to the inlet of the aromatics extraction unit.

[0013] Specifically, the pretreatment device is used to remove salt and water from crude oil to obtain desalted and dehydrated crude oil.

[0014] Specifically, the sodium desulfurization unit uses sodium and hydrogen to remove sulfur impurities from crude oil to produce desulfurized crude oil. The sulfur can be used to produce sulfur.

[0015] Specifically, the alkali neutralization device converts the sodium hydrosulfide produced by the sodium desulfurization device into sodium sulfide, which is then introduced into the sodium-sulfur electrolysis cell.

[0016] Specifically, the sodium-sulfur electrolysis cell electrolyzes sodium sulfide under the action of electric current to obtain metallic sodium, which can be reused for desulfurization.

[0017] Specifically, the lithium denitrification device uses lithium and hydrogen to remove impurity nitrogen in crude oil to obtain decontaminated and upgraded oil.

[0018] Specifically, the lithium-nitrogen electrolytic cell electrolyzes lithium nitride under the action of electric current to obtain metallic lithium, which is then reused for repeated denitrification.

[0019] Furthermore, the system for producing chemical raw materials from crude oil also includes a hydrogen pipeline network.

[0020] The reformed hydrogen produced by the catalytic reforming unit and the hydrogen produced by the ethylene cracking unit are introduced into the hydrogen pipeline network.

[0021] The hydrogen produced by the heating furnace is introduced into the hydrogen pipeline network, and the generated electricity is supplied to the sodium-sulfur electrolytic cell and the lithium-nitrogen electrolytic cell in the impurity removal subsystem.

[0022] Specifically, in the system for producing chemical raw materials from crude oil,

[0023] The pretreatment device removes salt and water from the crude oil to obtain desalted and dehydrated crude oil; the desalted and dehydrated crude oil is passed into the sodium desulfurization device to remove the impurity sulfur in the crude oil under the action of sodium and hydrogen to obtain desulfurized crude oil; the desulfurized crude oil is passed into the lithium denitrification device to remove the impurity nitrogen in the crude oil under the action of lithium and hydrogen to obtain decontaminated and upgraded oil; the sodium hydrosulfide produced in the sodium desulfurization device is passed into the alkali neutralization device to be converted into sodium sulfide and passed into the sodium-sulfur electrolysis cell; the sodium The sodium sulfide produced in the desulfurization device is also introduced into the sodium-sulfur electrolytic cell; sodium sulfide is converted into sodium and sulfur under the action of electric current; the produced sodium is introduced into the sodium desulfurization device so that the metallic sodium is recycled, and the produced sulfur can be used to make sulfur; the lithium nitride produced in the lithium denitrification device is introduced into the lithium-nitrogen electrolytic cell; lithium nitride is converted into lithium and nitrogen under the action of electric current; the produced lithium is introduced into the lithium denitrification device so that the metallic lithium is recycled; the decontaminated and upgraded oil produced by the lithium denitrification device is introduced into the flash tank;

[0024] The light hydrocarbons below C5 and naphtha produced in the flash tank are passed into the light hydrocarbon recovery unit to separate the light hydrocarbons below C5 and naphtha; hydrogen and the distillate oil produced in the flash tank are passed into the ebullated bed hydrocracking unit to produce acid gas, dry gas, liquefied gas, light naphtha, heavy naphtha, diesel, wax oil and residual oil; the naphtha separated in the light hydrocarbon recovery unit is passed into the catalytic reforming unit to produce reformed hydrogen, reformed dry gas, reformed liquefied gas, reformed C5 and reformed gasoline; the light hydrocarbons below C5 produced in the light hydrocarbon recovery unit are passed into the ethylene cracking unit;

[0025] The reformed C5 produced by the catalytic reforming unit is passed into the ethylene cracking unit; the reformed gasoline produced by the catalytic reforming unit is passed into the aromatics extraction unit; the light naphtha produced by the ebullated bed hydrocracking unit is passed into the ethylene cracking unit; the heavy naphtha produced by the ebullated bed hydrocracking unit is passed into the catalytic reforming unit; the diesel and wax oil produced by the ebullated bed hydrocracking unit are passed into the hydrocracking unit; the residual oil produced by the ebullated bed hydrocracking unit is passed into the heating furnace; the BTX produced by the aromatics extraction unit is used as a product; the aromatics extraction unit produces The raffinate is passed into the ethylene cracking unit; the C9+ aromatics produced by the aromatics extraction unit are passed into the hydrocracking unit; the light naphtha and hydrogenated tail oil produced by the hydrocracking unit are passed into the ethylene cracking unit; the heavy naphtha produced by the hydrocracking unit is passed into a catalytic reforming unit; the ethylene, propylene and C4 fractions produced by the ethylene cracking unit are used as products; the ethylene gasoline produced by the ethylene cracking unit is passed into a pyrolysis gasoline hydrogenation unit, and the produced ethylene tar is passed into a heating furnace; the hydrogenated gasoline produced by the pyrolysis gasoline hydrogenation unit is passed into the aromatics extraction unit.

[0026] The present invention also provides a method for producing chemical raw materials from crude oil, using the above-mentioned system for producing chemical raw materials from crude oil, the method comprising:

[0027] S1: Impurity removal process

[0028] The crude oil is passed through the pretreatment device for desalting and dehydration to obtain desalted and dehydrated crude oil; the desalted and dehydrated crude oil is passed through the sodium desulfurization device to remove the impurity sulfur in the crude oil under the action of sodium and hydrogen to obtain desulfurized crude oil; the desulfurized crude oil is passed through the lithium denitrification device to remove the impurity nitrogen in the crude oil under the action of lithium and hydrogen to obtain decontaminated and upgraded oil; the sodium hydrosulfide produced in the sodium desulfurization device is passed through the alkali neutralization device to be converted into sodium sulfide and passed through the sodium-sulfur electrolysis cell; The sodium sulfide produced in the sodium desulfurization device is also introduced into the sodium-sulfur electrolytic cell; sodium sulfide is converted into sodium and sulfur under the action of electric current; the produced sodium is introduced into the sodium desulfurization device so that the metallic sodium is recycled, and the produced sulfur can be used to make sulfur; the lithium nitride produced in the lithium denitrification device is introduced into the lithium-nitrogen electrolytic cell; lithium nitride is converted into lithium and nitrogen under the action of electric current; the produced lithium is introduced into the lithium denitrification device so that the metallic lithium is recycled; the decontaminated and upgraded oil produced by the lithium denitrification device is introduced into the flash tank;

[0029] S2: Classification processing

[0030] The produced decontaminated and upgraded oil is passed into a flash tank to generate light hydrocarbons below C5, naphtha, and distillate oil; the light hydrocarbons below C5 and naphtha are passed into the light hydrocarbon recovery unit to separate the light hydrocarbons below C5 and naphtha; the separated naphtha is passed into the catalytic reforming unit to produce reformed hydrogen, reformed dry gas, reformed liquefied gas, reformed C5, and reformed gasoline; the distillate oil is passed into the ebullated bed hydrocracking unit to produce acid gas, dry gas, liquefied gas, light naphtha, heavy naphtha, diesel, wax oil, and residual oil; the produced acid gas is passed into the alkali neutralization unit of the impurity removal process;

[0031] S3: Product refining process

[0032] The reformed gasoline is passed into the aromatics extraction unit to generate BTX, raffinate and C9+ aromatics; the light hydrocarbons below C5, reformed C5, light naphtha and raffinate are passed into the ethylene cracking unit to generate hydrogen, ethylene, propylene and C4 fraction, ethylene gasoline and ethylene tar; the generated ethylene gasoline is passed into the pyrolysis gasoline hydrogenation unit, and the produced hydrogenated gasoline is passed into the aromatics extraction unit; the diesel and wax oil produced in the ebullated bed hydrocracking unit and the C9+ aromatics produced in the aromatics extraction unit are passed into the hydrocracking unit, the produced light naphtha and hydrogenated tail oil are passed into the ethylene cracking unit, and the produced heavy naphtha is passed into the catalytic reforming unit; the residual oil and ethylene tar produced in the ebullated bed hydrocracking unit are passed into the heating furnace.

[0033] Furthermore, the reformed hydrogen produced by the catalytic reforming unit and the hydrogen generated by the ethylene cracking unit are introduced into the hydrogen pipeline network.

[0034] Furthermore, the hydrogen in the hydrogen pipeline network is respectively introduced into the ebullated bed hydrocracking unit, the pyrolysis gasoline hydrogenation unit and the hydrocracking unit.

[0035] Furthermore, the crude oil includes light crude sand and medium crude sand, for example, a mixture of the two in a ratio of 1:1.

[0036] Unless otherwise specified, the technical terms in this invention are commonly used in the art.

[0037] Light hydrocarbons below C5: refers to light hydrocarbons below C5 produced by distillation after crude oil is decontaminated.

[0038] Distillate oil: refers to the distillate oil that is heavier than naphtha and produced by distillation after crude oil is removed from impurities.

[0039] Reforming C5: refers to the C5 fraction produced by naphtha through the reforming unit, which is generally straight-chain pentane, etc.

[0040] BTX: refers to a mixture of benzene, toluene and xylene, also known as light aromatics.

[0041] C9+ aromatics: refers to the C9+ aromatics produced by reformed gasoline through an aromatics extraction unit, generally C9 and above aromatics.

[0042] C4 fraction: refers to the C4 fraction produced by ethylene cracking unit, which is generally butadiene, n-butene, isobutene and a small amount of n-butane and isobutane.

[0043] C5-: refers to the pyrolysis gasoline that has been treated with a pyrolysis gasoline hydrogenation unit to remove C5 and C5 hydrocarbons, which are generally unsaturated chain olefins.

[0044] C9+: refers to pyrolysis gasoline that has been treated with a pyrolysis gasoline hydrogenation unit to remove C9 and higher hydrocarbons, generally cyclic olefins, styrene, etc.

[0045] Compared with the prior art, the present invention has at least one of the following advantages:

[0046] 1) The atmospheric and vacuum primary processing device is cancelled, repeated heat exchange is reduced, and the multiple distillation processes are simplified to a single distillation process of the product, while saving the energy consumption of large atmospheric and vacuum devices.

[0047] 2) The productivity of chemical products is improved, and crude oil is effectively converted into chemical raw materials and chemical products.

[0048] 3) Efficient utilization of intermediate products. Alkali metal desulfurization and denitrification are used, and then the alkali metals are recycled in the electrolytic cell. Heavy naphtha is converted into olefin products and aromatics feedstock through catalytic reforming and aromatics extraction. C9+ aromatics, diesel, and wax oil are converted into ethylene feed and reforming feed through hydrocracking. Residual oil and tar are converted into fuel in the heating furnace to supply electricity to the electrolytic cell, generating hydrogen for hydrogen consumption replenishment. The entire system achieves 100% intermediate product utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 This is a schematic diagram of the system and overall process flow of the method for producing chemical raw materials from crude oil according to an embodiment of the present invention.

[0050] Figure 2 This is a schematic diagram of the impurity removal subsystem i and its flow chart in a system for producing chemical raw materials from crude oil according to an embodiment of the present invention.

[0051] Figure 3 This is a schematic diagram of the classification processing subsystem II and its flow chart in the system for producing chemical raw materials from crude oil according to an embodiment of the present invention.

[0052] Figure 4 This is a schematic diagram of the product refining subsystem III and its flow chart in a system for producing chemical raw materials from crude oil according to an embodiment of the present invention.

[0053] Figure 5 This is a schematic diagram of a sodium-sulfur electrolysis cell device according to an embodiment of the present invention.

[0054] Figure 6 Schematic diagram of a lithium-nitrogen electrolytic cell device according to an embodiment of the present invention.

[0055] Reference numerals:

[0056] i-impurity removal subsystem; ii-classification processing subsystem; iii-product refining subsystem;

[0057] A-pretreatment unit; B-sodium desulfurization unit; C-alkali neutralization unit; D-sodium-sulfur electrolytic cell; E-lithium denitrification unit; F-lithium-nitrogen electrolytic cell; G-flash tank; H-catalytic reforming unit; I-ebullated-bed hydrocracking unit; J-light hydrocarbon recovery unit; K-aromatics extraction unit; L-ethylene cracking unit; M-hydrocracking unit; N-hydrogen pipeline network; O-heating furnace; P-pyrolysis gasoline hydrogenation unit;

[0058] 1-Crude oil; 2-Hydrogen; 3-Sodium; 4-Desalted and dehydrated crude oil; 5-Desulfurized crude oil; 6-Sodium hydrosulfide; 7-Sodium sulfide; 8-Sulfur; 9-Lithium; 10-Decontaminated and upgraded oil; 11-Lithium nitride; 12-Nitrogen; 13-Light hydrocarbons below C5; 14-Naphtha; 15-Distillate oil; 16-Reforming hydrogen; 17-Reforming dry gas; 18-Reforming liquefied petroleum gas; 19-Reforming C5; 20-Heavy Whole gasoline; 21-acid gas; 22-dry gas; 23-liquefied gas; 24-light naphtha; 25-heavy naphtha; 26-diesel; 27-wax oil; 28-residue oil; 29-BTX; 30-raffinate oil; 31-C9+ aromatics; 32-ethylene; 33-propylene; 34-C4 fraction; 35-ethylene gasoline; 36-ethylene tar; 37-hydrogenated gasoline, 38-hydrogenated tail oil. DETAILED DESCRIPTION

[0059] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0060] like Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, a system for producing chemical raw materials using crude oil includes: an impurity removal subsystem i (see Figure 2 ), classification processing subsystem ii (see Figure 3 ) and product refinement subsystem iii (see Figure 4 ).

[0061] Please refer to Figure 1 and Figure 2 The impurity removal subsystem i includes a pretreatment device A, a sodium desulfurization device B, an alkali neutralization device C, a sodium-sulfur electrolytic cell D, a lithium denitrification device E, and a lithium-nitrogen electrolytic cell F;

[0062] The outlet of the pretreatment device A is connected to the inlet of the sodium desulfurization device B (the pretreatment device A removes salt and water from the crude oil 1 to obtain a desalted and dehydrated crude oil 4; the desalted and dehydrated crude oil 4 is passed into the sodium desulfurization device B, where the impurity sulfur in the crude oil is removed under the action of sodium 3 and hydrogen 2 to obtain a desulfurized crude oil 5);

[0063] The outlet of the sodium desulfurization device B is connected to the inlet of the lithium denitrification device E, the inlet of the alkali neutralization device C, and the inlet of the sodium-sulfur electrolytic cell D (the desulfurized crude oil 5 is passed into the lithium denitrification device E, and the impurity nitrogen in the crude oil is removed under the action of lithium 9 and hydrogen 2 to generate desulfurized and upgraded oil 10 and lithium nitride 11);

[0064] The sodium hydrosulfide 6 produced in the sodium desulfurization device B is passed into the alkali neutralization device C to be converted into sodium sulfide 7; the sodium sulfide 7 produced in the sodium desulfurization device B is passed into the sodium-sulfur electrolysis cell D;

[0065] The outlet of the alkali neutralization device C is connected to the inlet of the sodium-sulfur electrolytic cell D (the sodium sulfide 7 produced in the alkali neutralization device C is also passed into the sodium-sulfur electrolytic cell D);

[0066] The outlet of the sodium-sulfur electrolytic cell D is connected to the inlet of the sodium-based desulfurization device B (the sodium-sulfur electrolytic cell D converts sodium sulfide 7 into sodium 3 and sulfur 8 under the action of electric current, and the generated sodium 3 is passed into the sodium-based desulfurization device B so that the metallic sodium 3 is recycled; the generated sulfur 8 can be used to produce sulfur).

[0067] The outlet of the lithium denitrification device E is connected to the inlet of the lithium-nitrogen electrolytic cell F (the lithium nitride 11 produced in the lithium denitrification device E is passed into the lithium-nitrogen electrolytic cell F; the lithium nitride 11 is converted into lithium 9 and nitrogen 12 under the action of the current);

[0068] The outlet of the lithium-nitrogen electrolytic cell F is connected to the inlet of the lithium-based denitrification device E (the lithium 9 produced in the lithium-nitrogen electrolytic cell F is passed into the lithium-based denitrification device E to circulate the metallic lithium 9).

[0069] The outlet of the lithium denitrification device E produces decontaminated and upgraded oil 10.

[0070] Please refer to Figure 1 and Figure 3 , the classification processing subsystem ii includes a flash tank G, a light hydrocarbon recovery unit J, a catalytic reforming unit H and an ebullated bed hydrocracking unit I;

[0071] The outlet of the lithium denitrification device E in the impurity removal subsystem i is connected to the inlet of the flash tank G in the classification processing subsystem ii (the de-impurified and upgraded oil 10 produced by the lithium denitrification device E is passed into the flash tank G);

[0072] The outlet of the flash tank G is connected to the inlet of the light hydrocarbon recovery unit J and the inlet of the ebullated bed hydrocracking unit I (the light hydrocarbons 13 below C5 and naphtha 14 produced in the flash tank G are introduced into the light hydrocarbon recovery unit J to separate the light hydrocarbons 13 below C5 (as ethylene material) and naphtha 14 (as reforming material); the hydrogen 12 and the distillate oil 15 produced in the flash tank G (as cracking material) are introduced into the ebullated bed hydrocracking unit I to produce acid gas 21, dry gas 22, liquefied gas 23, light naphtha 24, heavy naphtha 25, diesel 26, wax oil 27 and residual oil 28).

[0073] Please refer to Figure 1 、 Figure 3 and Figure 4 , the product refining subsystem iii includes an aromatics extraction unit K, an ethylene cracking unit L, a hydrocracking unit M, a pyrolysis gasoline hydrogenation unit P and a heating furnace O;

[0074] The outlet of the light hydrocarbon recovery unit J is connected to the inlet of the catalytic reforming unit H and the inlet of the ethylene cracking unit L in the product refining subsystem iii (the light hydrocarbons 13 below C5 separated by the light hydrocarbon recovery unit J are passed to the ethylene cracking unit L; the naphtha 14 separated in the light hydrocarbon recovery unit J is passed to the catalytic reforming unit H to produce reformed hydrogen 16, reformed dry gas 17, reformed liquefied gas 18, reformed C5 19 and reformed gasoline 20).

[0075] The outlet of the catalytic reforming unit H is connected to the inlet of the hydrogen pipeline network N, the inlet of the ethylene cracking unit L, and the inlet of the aromatics extraction unit K (the reformed hydrogen 16 produced by the catalytic reforming unit H is passed into the hydrogen pipeline network N for convergence; the reformed C5 19 produced is passed into the ethylene cracking unit L; and the reformed gasoline 20 produced is passed into the aromatics extraction unit K);

[0076] The outlet of the ebullated bed hydrocracking unit I is connected to the inlet of the alkali neutralization unit C, the inlet of the ethylene cracking unit L, the inlet of the catalytic reforming unit H, the inlet of the hydrocracking unit M, and the inlet of the heating furnace O (the acid gas 21 produced by the ebullated bed hydrocracking unit I is passed into the alkali neutralization unit C; the light naphtha 24 produced is passed into the ethylene cracking unit L; the heavy naphtha 25 produced is passed into the catalytic reforming unit H; the diesel 26 and wax oil 27 produced are passed into the hydrocracking unit M; and the residual oil 28 produced is passed into the heating furnace O);

[0077] The outlet of the aromatics extraction unit K is connected to the inlet of the ethylene cracking unit L and the inlet of the hydrocracking unit M (the BTX 29 produced by the aromatics extraction unit K is used as a product; the raffinate 30 produced is passed to the ethylene cracking unit L; and the C9+ aromatics 31 produced is passed to the hydrocracking unit M);

[0078] The outlet of the hydrocracking unit M is connected to the inlet of the ethylene cracking unit L and the inlet of the catalytic reforming unit H (the light naphtha 24 and hydrogenated tail oil 38 produced by the hydrocracking unit M are passed into the ethylene cracking unit L; the heavy naphtha 25 produced is passed into the catalytic reforming unit H);

[0079] The outlet of the ethylene cracking unit L is connected to the inlet of the hydrogen pipeline network N, the inlet of the pyrolysis gasoline hydrogenation unit P, and the inlet of the heating furnace O (the hydrogen 2 produced by the ethylene cracking unit L is passed into the hydrogen pipeline network N for convergence; the produced ethylene 32, propylene 33, and C4 fraction 34 are products; the produced ethylene gasoline 35 is passed into the pyrolysis gasoline hydrogenation unit P; and the produced ethylene tar 36 is passed into the heating furnace O);

[0080] The outlet of the pyrolysis gasoline hydrogenation unit P is connected to the inlet of the aromatics extraction unit K (the hydrogenated gasoline 37 produced by the pyrolysis gasoline hydrogenation unit P is passed into the aromatics extraction unit K).

[0081] In addition, the reformed dry gas 17 produced by the catalytic reformer H and the dry gas 22 produced by the ebullated bed hydrocracking unit 1 are combined as dry gas for self-use. The reformed liquefied gas 18 produced by the catalytic reformer H and the liquefied gas 23 produced by the ebullated bed hydrocracking unit 1 are combined as liquefied gas for self-use.

[0082] See Figure 2 The impurity removal subsystem i includes a pretreatment device A, a sodium desulfurization device B, an alkali neutralization device C, a sodium-sulfur electrolytic cell D, a lithium-denitrification device E, and a lithium-nitrogen electrolytic cell F. The devices are connected as follows: the outlet of the pretreatment device A is connected to the inlet of the sodium desulfurization device B; the outlet of the sodium desulfurization device B is connected to the inlet of the lithium-denitrification device E, the inlet of the alkali neutralization device C, and the inlet of the sodium-sulfur electrolytic cell D; the outlet of the alkali neutralization device C is connected to the inlet of the sodium-sulfur electrolytic cell D; the outlet of the sodium-sulfur electrolytic cell D is connected to the inlet of the sodium desulfurization device B to recycle metallic sodium; the outlet of the lithium-denitrification device E is connected to the inlet of the lithium-nitrogen electrolytic cell F; the outlet of the lithium-nitrogen electrolytic cell F is connected to the inlet of the lithium-denitrification device E to recycle metallic lithium; and the outlet of the lithium-denitrification device E produces decontaminated and upgraded oil 10.

[0083] The pretreatment unit A functions as both a desalting and a dehydrating unit. Desalting removes free and ionic chlorine impurities. When moisture is present in the low-temperature equipment, it prevents calcium chloride and magnesium chloride from hydrolyzing to produce highly corrosive hydrochloric acid. As the water evaporates, salt scale forms on the walls of the heating furnace (which is included in the pretreatment unit A), reducing heat transfer efficiency and increasing flow resistance. In severe cases, this can lead to pipe blockages and burn-throughs, potentially causing accidents. Dehydration reduces equipment load. In the distillation tower, excessive water vaporization increases the gas phase volume, increasing pressure drop within the tower and potentially causing operational accidents such as tower blowouts. The water content of the pretreatment unit A is controlled between 0.1% and 0.2%, and the salt content is kept below 5 mg / L. This unit utilizes a two-stage crude oil desalting and dehydration process, comprising a primary desalting tank and a secondary desalting tank.

[0084] The sodium desulfurization device B is used to remove the sulfur impurity in crude oil using a certain ratio of sodium and hydrogen, recovering the sodium for reuse and using the sulfur to produce sulfur. The reaction mechanism is:

[0085] RS-R'+2Na+H2=R-H+R'-H+Na2S

[0086] 2R-S-R'+2Na+3H2=2R-H+2R'-H+2NaHS

[0087] NaHS+NaOH=Na2S+H2O;Na2S x →2Na+xS

[0088] Wherein, RS-R' represents sulfur-containing crude oil, R and R' represent carbon chains connected to S, and x represents the number of sulfur atoms in the sodium polysulfide molecule.

[0089] Sodium desulfurization unit B uses an axial flow turbine agitator with a temperature of 100-120°C, n = 10-300 r / min, and v = 4-10 m / s. This allows the molten sodium to fully react with the crude oil. Here, n represents the agitator speed, and v represents the blade tip linear velocity.

[0090] The alkali neutralization device C is used to convert the NaHS produced by the sodium desulfurization device B into Na2S, which is then passed into the sodium-sulfur electrolysis cell D to electrolyze to obtain metallic sodium for repeated desulfurization use.

[0091] The sodium-sulfur electrolytic cell D is used to: pass the current through the molten sodium sulfide electrolyte, the anode is connected to the positive electrode of the power supply, and the Na2S x =2Na+xS+2e - Oxidation reaction occurs, the cathode is connected to the negative electrode, 2Na+2e - =2Na undergoes reduction reaction, the overall reaction formula is: Na2S x→2Na+xS is a device that converts electrical energy into chemical energy. See the schematic diagram of this device. Figure 5 .

[0092] The lithium denitrification device E is used to remove nitrogen impurities from crude oil using a certain ratio of lithium and hydrogen, and to recover the lithium for reuse. The reaction mechanism is as follows:

[0093] +6Li+3H2=2R-H+2R'-H+2R”-H+2Li3N

[0094] in, represents nitrogen-containing crude oil, and R, R' and R" represent carbon chains connected to nitrogen.

[0095] The lithium denitrification device E uses an axial flow turbine agitator with a temperature of 180-190°C, n = 10-300 r / min, and v = 4-10 m / s, which can fully contact and react the molten lithium with the crude oil. Where n represents the agitator speed and v represents the blade tip linear velocity.

[0096] The lithium nitrogen electrolytic cell F has the following functions: the current passes through the molten lithium nitride electrolyte, the anode is connected to the positive electrode of the power supply, and the 2N 3- -6e - =3N2, oxidation reaction occurs, cathode is connected to negative electrode, 6Li + +6e - =6Li, a reduction reaction occurs, the overall reaction formula is: 2Li3N→6Li+3N2, which is a device that converts electrical energy into chemical energy. The schematic diagram of the device can be found in Figure 6 .

[0097] See Figure 3 The classification processing subsystem ii includes a flash tank G, a light hydrocarbon recovery unit J, a catalytic reforming unit H, and an ebullated-bed hydrocracking unit I. The units are connected as follows: the decontaminated and upgraded oil 10 produced at the outlet of the lithium denitrification unit E in the impurity removal subsystem i is passed to the inlet of the flash tank G in the classification processing subsystem ii. The outlet of the flash tank G is connected to the inlet of the light hydrocarbon recovery unit J and the inlet of the ebullated-bed hydrocracking unit I. The outlet of the light hydrocarbon recovery unit J is connected to the inlet of the catalytic reforming unit H and the inlet of the ethylene cracking unit L in the product refining subsystem iii. Some intermediate products produced at the outlets of the catalytic reforming unit H and the ebullated-bed hydrocracking unit I are passed to the product refining subsystem iii.

[0098] The decontaminated and upgraded oil 10 produced by the impurity removal subsystem i is fed into the classification processing subsystem ii, where it passes through a flash tank G to generate light hydrocarbons 13 (less than C5), naphtha 14, and distillate 15. The light hydrocarbons 13 (less than C5) and naphtha 14 are then separated by a light hydrocarbon recovery unit J. The resulting light hydrocarbons 13 (less than C5) are fed as ethylene feed to the ethylene cracking unit L in the product refining subsystem iii. The resulting naphtha 14 is fed as reforming feed to the catalytic reforming unit H in the classification processing subsystem ii, producing reformed hydrogen 16, reformed dry gas 17, reformed liquefied petroleum gas 18, reformed C5 19, and reformed gasoline 20. The resulting distillate 15 is fed as cracking feed to the ebullating bed hydrocracking unit I, producing acid gas 21, dry gas 22, liquefied petroleum gas 23, light naphtha 24, heavy naphtha 25, diesel 26, wax oil 27, and residual oil 28.

[0099] The acid gas 21 produced by the ebullated-bed hydrocracking unit I in the classification processing subsystem ii is passed to the alkali neutralization unit C in the impurity removal subsystem i, where it is neutralized with alkali to produce sodium sulfide 7 (the subsequent destination of the sodium sulfide can be found above). The resulting heavy naphtha 25 is passed as reforming material to the catalytic reforming unit H in the classification processing subsystem ii. The reformed hydrogen 16 produced by the catalytic reforming unit H is passed to the hydrogen pipeline network N for convergence and provides hydrogen usage for the sodium desulfurization unit B and lithium denitrification unit E in the impurity removal subsystem i, the ebullated-bed hydrocracking unit I in the classification processing subsystem ii, the hydrocracking unit M in the product refining subsystem iii, and the pyrolysis gasoline hydrogenation unit P.

[0100] Flash tank G distills crude oil, rapidly boiling and vaporizing it, and performing two-phase separation, reducing heat exchange processes and energy consumption. Light hydrocarbons 13 (C5 and below), naphtha 14, and distillate 15 are produced as ethylene feed, reforming feed, and cracking feed, respectively. Flash tank G primarily consists of a flash chamber, a heat exchange chamber, and a pressure reducing valve. Temperatures are controlled between 80 and 95°C, and pressures are controlled between 0.6 and 2 MPa.

[0101] The catalytic reforming unit H is used to dehydrogenate and rearrange the molecular structure of cycloalkanes in naphtha under the conditions of a catalyst to form reformed gasoline rich in aromatics to produce benzene, toluene and xylene. In addition, the by-product hydrogen is an important source of hydrogen for hydrogenation units (such as hydrocracking and ethylene gasoline hydrogenation). The catalytic reforming unit H adopts a continuous reforming process, which includes a reactor, a heating furnace (which comes with the catalytic reforming unit H), a stabilizing tower, a compressor, and a separator. The reactor temperature is controlled at 480-530°C, the pressure is controlled at 0.25-1.8 MPa, and the air velocity is controlled at 1.2-2.2 h -1 , the catalyst is a zeolite molecular sieve catalyst.

[0102] The function of the ebullated bed hydrocracking unit I is to cause the distillate oil to undergo hydrogenation, cracking and isomerization reactions in the presence of hydrogen and a catalyst, and to convert it into light oil in order to prepare raw materials for chemical products. The ebullated bed hydrocracking unit I (reactor) adopts an ebullated bed hydrocracking process, which includes a heat exchanger, a heating furnace (provided by the ebullated bed hydrocracking unit I), an ebullated bed reactor, an air cooler, a high-pressure separator, a low-pressure separator, a compressor, a stabilizing tower, and a fractionating tower. The reactor temperature is controlled at 300-470°C, the pressure is controlled at 6.5-22.5MPa, and the air velocity is controlled at 1.0-2.0h -1 The hydrogen-to-oil ratio is between 1000 and 1500, and the catalyst is a microspherical catalyst.

[0103] See Figure 4 The product refining subsystem iii includes an aromatics extraction unit K, an ethylene cracking unit L, a hydrocracking unit M, a pyrolysis gasoline hydrogenation unit P, and a heating furnace O. The units are connected as follows: the reformed C5 19 produced at the outlet of the catalytic reforming unit H in the classification processing subsystem ii is passed to the ethylene cracking unit L; the resulting reformed gasoline 20 is passed to the aromatics extraction unit K; the light naphtha 24 produced at the outlet of the ebullated-bed hydrocracking unit I in the classification processing subsystem ii is passed to the ethylene cracking unit L; the resulting heavy naphtha 25 is passed to the catalytic reforming unit H in the classification processing subsystem ii; the resulting diesel 26 and wax oil 27 are passed to the hydrocracking unit M; and the resulting residual oil 28 is passed to the heating furnace O.

[0104] The BTX 29 produced at the outlet of the aromatics extraction unit K is the product; the raffinate 30 produced is fed to the ethylene cracking unit L; and the C9+ aromatics 31 produced is fed to the hydrocracking unit M.

[0105] The light naphtha 24 and hydrogenated tail oil 38 produced at the outlet of the hydrocracking unit M are introduced into the ethylene cracking unit L; the produced heavy naphtha 25 is introduced into the catalytic reforming unit H in the classification processing subsystem ii.

[0106] The hydrogen 2 produced at the outlet of the ethylene cracking unit L is passed into the hydrogen pipeline N; the produced ethylene 32, propylene 33, and C4 fraction 34 are products; the produced ethylene gasoline 35 is passed into the cracking gasoline hydrogenation unit P; and the produced ethylene tar 36 is passed into the heating furnace O.

[0107] The hydrogenated gasoline 37 produced at the outlet of the pyrolysis gasoline hydrogenation unit P is introduced into the aromatics extraction unit K.

[0108] The hydrogen produced at the outlet of the heating furnace O is introduced into the hydrogen pipeline N of the entire system; the electricity produced is supplied to the sodium-sulfur electrolytic cell D and the lithium-nitrogen electrolytic cell F in the impurity removal subsystem i.

[0109] In addition, the reformed dry gas 17 produced by the catalytic reformer H and the dry gas 22 produced by the ebullated bed hydrocracking unit 1 are combined as dry gas for self-use. The reformed liquefied gas 18 produced by the catalytic reformer H and the liquefied gas 23 produced by the ebullated bed hydrocracking unit 1 are combined as liquefied gas for self-use.

[0110] The aromatics extraction unit K utilizes a combination of solvent extraction and distillation, using reformate oil, hydrocracking gasoline, and other raw materials, and sulfolane as a solvent, to effectively separate aromatics from non-aromatics through extraction. The mixed aromatics are then distilled to produce high-purity products such as benzene and toluene. Aromatics Extraction Unit K utilizes a sulfolane extraction process and includes an extraction tower, a reflux aromatics tank, a stripping tower, a recovery tower, an aromatics tank, a raffinate oil scrubber, a solvent regeneration tower, and a stripping tower. The extraction tower temperature is controlled between 60 and 95°C, the pressure between 0.3 and 0.8 MPa, and the solvent ratio is controlled between 2 and 3. The stripping tower pressure is controlled between 0.1 and 0.5 MPa, and the temperature is controlled between 100 and 130°C (top / bottom). The temperature of the recovery tower is controlled at 50-80 / 150-190°C (tower top / tower bottom), and the pressure is controlled at 0.02-0.05 MPa.

[0111] The ethylene cracker L, described above, is a process that involves chain scission and dehydrogenation of larger hydrocarbon molecules at high temperatures to produce smaller molecules of ethylene, propylene, and C4 fractions, which can be sold as commercial products. The ethylene cracker L utilizes tubular furnace cracking technology and consists of three components: a convection section, a radiant section (including radiant furnace tubes and burners), and a quench boiler system. The cracking reaction occurs in the radiant section, producing products such as small olefins. The convection section recovers waste heat from the high-temperature flue gas to gasify and superheat the feedstock to the required crossover temperature, while also preheating boiler feedwater and ultra-high-pressure steam. The quench boiler system terminates the secondary cracking reactions and recovers the high-temperature heat of the cracked gas to generate ultra-high-pressure steam. The temperature is controlled between 600 and 800°C, and the pressure is controlled between 0.05 MPa and 0.20 MPa.

[0112] The hydrocracking unit M is essentially an organic combination of hydrogenation and catalytic cracking processes. On the one hand, it can convert heavy oil products into light oil products such as gasoline through cracking reactions, and on the other hand, it can prevent the generation of large amounts of coke as in catalytic cracking. In addition, it can remove sulfur, chlorine, and oxygen compound impurities in the raw materials through hydrogenation. The hydrocracking unit M adopts a one-stage hydrocracking process with a temperature controlled at 440-650°C, a pressure controlled at 6.5-25.5 MPa, and a space velocity controlled at 1.0-5.0 h -1 The hydrogen-to-oil ratio is between 800 and 2000, and the catalyst is a microspherical catalyst.

[0113] The pyrolysis gasoline hydrogenation unit P, described above, functions to remove C5- and C9+ from cracked crude gasoline under hydrogen conditions before introducing it into a hydrogenation system to produce hydrogenated gasoline. The unit utilizes a center-cut hydrogenation process, comprising a C5 removal tower system, a C9 removal tower system, a first-stage hydrogenation system, and a second-stage hydrogenation system. The first-stage hydrogenation reaction temperature is approximately 40°C, while the second-stage hydrogenation reaction temperature is approximately 240°C. Pressures are controlled between 2.5 and 3.5 MPa.

[0114] The heating furnace O is designed to combust unused materials from the process, such as residual oil and tar, and convert the heat into electricity and other energy sources. It utilizes combined oil and gas combustion technology and consists of four components: an air supply system, an ignition system, a fuel system, and an electronic control system. The burner temperature is controlled between 350 and 600°C, and the fuel nozzle pressure is controlled between 0.2 and 10 MPa.

[0115] The method for producing chemical raw materials using the above-mentioned system for producing chemical raw materials from crude oil is summarized as follows:

[0116] Crude oil 1 and hydrogen 2 are introduced into the impurity removal subsystem i, where, after pretreatment, a decontaminated and upgraded oil 10 is obtained. The decontaminated and upgraded oil 10 is introduced into the classification processing subsystem ii, where it is distilled in a flash tank G to produce light hydrocarbons 13 below C5, naphtha 14, and distillate 15. The light hydrocarbons 13 below C5 and naphtha 14 are then separated in a light hydrocarbon recovery unit J. The naphtha 14 is introduced into the classification processing subsystem ii to produce reformed hydrogen 16, reformed dry gas 17, reformed liquefied gas 18, reformed C5 19, and reformed gasoline 20. The distillate 15 is introduced into the classification processing subsystem ii to produce acid gas 21, dry gas 22, liquefied gas 23, light naphtha 24, heavy naphtha 25, diesel 26, wax oil 27, and residual oil 28.

[0117] Light hydrocarbons 13 below C5, reformed C5 19, reformed gasoline 20, light naphtha 24, heavy naphtha 25, diesel 26, wax oil 27, and residual oil 28 produced by classification processing subsystem ii are fed into product refining subsystem iii. After undergoing secondary processing in subsystem iii, such as ethylene cracking and aromatic extraction, ethylene 32, propylene 33, C4 fraction 34, BTX 29, and residual hydrogen 2 are ultimately produced. Reformed dry gas 17 and dry gas 22 produced by classification processing subsystem ii are combined for self-use dry gas. Reformed liquefied gas 18 and liquefied gas 23 produced by classification processing subsystem ii are combined for self-use liquefied gas.

[0118] In some examples, dry gas can be used by the user; liquefied gas can be sold or used by the user.

[0119] In this application, hydrogen, ethylene, propylene, C4 fraction and BTX are final products.

[0120] Example 1

[0121] The following is a detailed description of a method for producing chemical raw materials using the above-mentioned system for producing chemical raw materials from crude oil.

[0122] like Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, a method for producing chemical raw materials from crude oil, using the above-mentioned system for producing chemical raw materials from crude oil, is as follows:

[0123] S1: Impurity removal process

[0124] like Figure 2 As shown, crude oil sand weighs 5 million tons and has a density of 857.40 kg / m 3 , residual carbon 4.28wt%, sulfur content 1.72wt%, nitrogen content 0.10wt%; 5 million tons of crude oil sand, density 871.40kg / m 3 , residual carbon 5.49wt%, sulfur content 2.93wt%, and nitrogen content 0.12wt%; after mixing, it is passed into pretreatment device A of impurity removal subsystem i for desalination and dehydration, with the temperature controlled at 105-140°C and the pressure controlled at 0.8-1.5MPa, to obtain desalted and dehydrated crude oil 4. Hydrogen 2, molten sodium 3, and desalted and dehydrated crude oil 4 are passed into sodium desulfurization device B to obtain desulfurized crude oil 5, sodium hydrosulfide 6, and sodium sulfide 7. Sodium hydrosulfide 6 is passed into alkali neutralization device C to react with alkali to produce sodium sulfide 7. Sodium sulfide 7 is passed into sodium-sulfur electrolysis cell D to obtain molten sodium 3 and sulfur 8. The electrolyzed molten sodium 3 is again passed into sodium desulfurization device B for recycling to remove impurity sulfur, and the electrolyzed sulfur 8 is used to produce sulfur. Desulfurized crude oil 5 is passed through a lithium denitrification unit E to produce decontaminated and upgraded crude oil 10 and lithium nitride 11. Lithium nitride 11 is then passed through a lithium-nitrogen electrolysis cell F to produce molten lithium 9 and nitrogen 12. The electrolyzed molten lithium 9 is then passed back through the lithium denitrification unit E for recycling to remove nitrogen impurities. The electrolyzed nitrogen 12 is then purified and released into the atmosphere.

[0125] S2: Classification processing

[0126] like Figure 3As shown, the decontaminated and upgraded oil 10 produced by the impurity removal subsystem i is passed into the classification processing subsystem ii, and passes through the flash tank G at a temperature of 80-95°C and a pressure of 0.6-2 MPa to generate light hydrocarbons 13 below C5, naphtha 14, and distillate oil 15. The light hydrocarbons 13 below C5 and naphtha 14 are separated by the light hydrocarbon recovery unit J. The light hydrocarbons 13 below C5 produced are used as ethylene feed and passed into the ethylene cracking unit L of the product refining subsystem iii; the naphtha 14 produced is used as reforming feed and passed into the catalytic reforming unit H of the classification processing subsystem ii, with a reaction temperature of 480-530°C, a pressure of 0.25-1.80 MPa, and an air velocity of 1.2-2.2 h / s. -1 The catalyst is a zeolite molecular sieve catalyst, and the output is reformed hydrogen 16, reformed dry gas 17, reformed liquefied gas 18, reformed C5 19 and reformed gasoline 20; the generated distillate oil 15 is passed into the ebullating bed hydrocracking unit I as the cracking material, and the reactor temperature is 300-470°C, the pressure is 6.5-22.5MPa, and the space velocity is 1.0-2.0h -1 The hydrogen-to-oil ratio is 1000-1500, and the catalyst is a microspherical catalyst, which produces acid gas 21, dry gas 22, liquefied gas 23, light naphtha 24, heavy naphtha 25, diesel 26, wax oil 27 and residual oil 28.

[0127] The acid gas 21 produced by the ebullated-bed hydrocracking unit I in the classification processing subsystem ii is passed to the alkali neutralization unit C in the impurity removal subsystem i, where it is neutralized with alkali, also producing sodium sulfide 7 (the subsequent destination of the sodium sulfide can be found above). The resulting heavy naphtha 25 is passed as reforming material to the catalytic reforming unit H in the classification processing subsystem ii. The reformed hydrogen 16 produced by the catalytic reforming unit H is passed to the hydrogen pipeline network N for convergence, and provides hydrogen usage for the sodium desulfurization unit B and lithium denitrification unit E in the impurity removal subsystem i, the ebullated-bed hydrocracking unit I in the classification processing subsystem ii, the hydrocracking unit M in the product refining subsystem iii, and the pyrolysis gasoline hydrogenation unit P.

[0128] S3: Product refining process

[0129] like Figure 4 As shown, the reformed gasoline 20 is introduced into the product refining subsystem iii aromatic extraction device K, the extraction tower temperature is 60-95°C, the pressure is 0.3-0.8 MPa, the solvent ratio is 2-3, the stripping tower temperature is 120 / 180°C (tower top / tower bottom), the pressure is 0.1-0.5 MPa, the recovery tower temperature is 60 / 170°C (tower top / tower bottom), the pressure is 0.02-0.05 MPa, and the product BTX29, raffinate 30, and C9+ aromatics 31 are generated.

[0130] Light hydrocarbons below C5 13, reformed C5 19, light naphtha 24, and raffinate 30 are fed into the ethylene cracker L of product refining subsystem III at a temperature of 600-800°C and a pressure of 0.05-0.20 MPa, generating hydrogen 2, ethylene 32, propylene 33, a C4 fraction 34, ethylene gasoline 35, and ethylene tar 36. Hydrogen 2 is fed into the hydrogen pipeline network N for merging, while ethylene 32, propylene 33, and the C4 fraction 34 are products.

[0131] Ethylene gasoline 35 is fed into the cracking gasoline hydrogenation unit P in product refining subsystem III. The first stage hydrogenation reaction is conducted at a temperature of 40-50°C and a pressure of 1.5-2.5 MPa. The second stage hydrogenation reaction is conducted at a temperature of 230-250°C and a pressure of 2.5-3.5 MPa, with a hydrogen-to-oil ratio of 300-600, to produce hydrogenated gasoline 37. Hydrogenated gasoline 37 is fed into the aromatics extraction unit K (see above for the subsequent process flow).

[0132] C9+ aromatics 31, diesel 26, and wax oil 27 are introduced into the product refining subsystem III hydrocracking unit M at a temperature of 440-650°C, a pressure of 6.5-25.5 MPa, and a space velocity of 1.0-5.0 h -1 The hydrogen-to-oil ratio is 800-2000, and a microspherical catalyst is used as the catalyst to produce light naphtha 24, heavy naphtha 25, and hydrogenated tail oil 38. The light naphtha 24 and hydrogenated tail oil 38 are fed into the ethylene cracking unit L to produce olefins, and the heavy naphtha 25 is fed back into the catalytic reforming unit H to produce reformed gasoline.

[0133] The residual oil 28 and ethylene tar 36 are introduced into the heating furnace O of the product refining subsystem iii, with the burner temperature being 350-600°C and the fuel nozzle pressure being 0.2-10 MPa. The generated hydrogen is introduced into the hydrogen pipeline N, and the generated electricity is supplied to the sodium-sulfur electrolytic cell D and the lithium nitride electrolytic cell F in the impurity removal subsystem i.

[0134] In addition, the reformed dry gas 17 produced by the catalytic reformer H and the dry gas 22 produced by the ebullated bed hydrocracking unit 1 are combined as dry gas for self-use. The reformed liquefied gas 18 produced by the catalytic reformer H and the liquefied gas 23 produced by the ebullated bed hydrocracking unit 1 are combined as liquefied gas for self-use.

[0135] In this application, hydrogen, ethylene, propylene, C4 fraction and BTX are final products.

[0136] Comparative Example 1

[0137] Taking a Sinopec integrated refining and chemical plant as an example, the difference between Comparative Example 1 and Example 1 is that Comparative Example 1 does not use a flash tank distillation device, but uses a conventional atmospheric and vacuum distillation device in a refinery; the impurity removal process of Comparative Example 1 does not include an alkali metal impurity removal process.

[0138] The remaining processes, including crude oil selection, device operating conditions, and device connection methods, were the same between Example 1 and Comparative Example 1. The crude oil properties are shown in Table 1, and the product distribution throughout the entire process is shown in Table 2.

[0139] Table 1 Crude oil properties

[0140]

[0141] Table 2 Product distribution of the whole process

[0142]

[0143]

[0144] The comparison results show that the light olefin yields of Example 1 and Comparative Example 1 are similar; the aromatics output of Example 1 is much greater than that of Comparative Example 1; Example 1 achieves self-sufficiency in hydrogen, with surplus hydrogen available for sale; due to the absence of a constant pressure reduction device, the utility consumption of Example 1 is lower than that of Comparative Example 1; Example 1 does not produce any fuel oil at all, but only produces chemical products such as olefins and aromatics, which can effectively address the problem of oil surplus and has significant economic benefits and stronger market competitiveness.

[0145] Although the present invention has been described in detail above using general descriptions and specific embodiments, it will be apparent to those skilled in the art that modifications and improvements may be made based on the present invention. Therefore, such modifications and improvements, which do not depart from the spirit of the present invention, are intended to be within the scope of protection claimed herein.

Claims

1. A system for producing chemical raw materials from crude oil, characterized in that: include: Impurity removal subsystem, classification processing subsystem and product refining subsystem; The impurity removal subsystem includes a pretreatment device, a sodium desulfurization device, an alkali neutralization device, a sodium-sulfur electrolytic cell, a lithium denitrification device, and a lithium-nitrogen electrolytic cell; The pretreatment device removes salt and water from the crude oil to obtain desalted and dehydrated crude oil; the desalted and dehydrated crude oil is passed into the sodium desulfurization device to obtain desulfurized crude oil; the desulfurized crude oil is passed into the lithium denitrification device to generate decontaminated and upgraded oil and lithium nitride; the sodium hydrosulfide and sodium sulfide produced in the sodium desulfurization device are respectively passed into the alkali neutralization device and the sodium-sulfur electrolytic cell, and the sodium produced in the sodium-sulfur electrolytic cell is passed into the sodium desulfurization device to recycle the metallic sodium; the lithium nitride is passed into the lithium-nitrogen electrolytic cell, and the lithium produced in the lithium-nitrogen electrolytic cell is passed into the lithium denitrification device to recycle the metallic lithium; The classification processing subsystem includes a flash tank, a light hydrocarbon recovery unit, a catalytic reforming unit, and an ebullated bed hydrocracking unit; The decontaminated and upgraded oil produced by the lithium denitrification device is passed into the flash tank; the light hydrocarbons below C5 and naphtha produced in the flash tank are passed into the light hydrocarbon recovery device, and the distillate oil produced by the flash tank is passed into the ebullated bed hydrocracking device; The product refining subsystem includes an aromatics extraction unit, an ethylene cracking unit, a hydrocracking unit, a pyrolysis gasoline hydrogenation unit, and a heating furnace; The light hydrocarbons below C5 and naphtha separated by the light hydrocarbon recovery unit are respectively introduced into the ethylene cracking unit and the catalytic reforming unit; the reformed C5 and reformed gasoline produced by the catalytic reforming unit are respectively introduced into the ethylene cracking unit and the aromatics extraction unit; the acid gas produced by the ebullated bed hydrocracking unit is introduced into the alkali neutralization unit, the light naphtha produced is introduced into the ethylene cracking unit, the heavy naphtha produced is introduced into the catalytic reforming unit, and the diesel and wax oil produced are introduced into the hydrocracking unit to produce The residual oil produced is passed into the heating furnace; the raffinate produced by the aromatics extraction unit is passed into the ethylene cracking unit, and the C9+ aromatics produced are passed into the hydrocracking unit; the light naphtha and hydrogenated tail oil produced by the hydrocracking unit are passed into the ethylene cracking unit, and the heavy naphtha produced is passed into the catalytic reforming unit; the ethylene gasoline produced by the ethylene cracking unit is passed into the pyrolysis gasoline hydrogenation unit, and the produced ethylene tar is passed into the heating furnace; the hydrogenated gasoline produced by the pyrolysis gasoline hydrogenation unit is passed into the aromatics extraction unit.

2. The system for producing chemical raw materials from crude oil according to claim 1, characterized in that: The sodium desulfurization device includes an axial flow turbine agitator.

3. The system for producing chemical raw materials from crude oil according to claim 1, characterized in that: The lithium denitrification device includes an axial flow turbine agitator.

4. The system for producing chemical raw materials from crude oil according to any one of claims 1 to 3, characterized in that: The system also includes a hydrogen pipeline network; The reformed hydrogen produced by the catalytic reforming unit and the hydrogen produced at the outlet of the ethylene cracking unit are introduced into the hydrogen pipeline network; and / or, The hydrogen produced at the outlet of the heating furnace is introduced into the hydrogen pipeline network.

5. A method for producing chemical raw materials using crude oil, characterized in that: Using the system for producing chemical raw materials from crude oil according to claim 1, the method comprises: S1: Impurity removal process The crude oil is passed through the pretreatment device for desalting and dehydration to obtain desalted and dehydrated crude oil; the desalted and dehydrated crude oil is passed through the sodium desulfurization device, and the impurity sulfur in the crude oil is removed under the action of sodium and hydrogen to obtain desulfurized crude oil; the desulfurized crude oil is passed through the lithium denitrification device, and part of the nitrogen in the crude oil is removed under the action of lithium and hydrogen to generate lithium nitride and decontaminated and upgraded oil; the sodium hydrosulfide produced in the sodium desulfurization device is passed through the alkali neutralization device and converted into sodium sulfide; the sodium sulfide produced in the sodium desulfurization device and the alkali neutralization device is passed through the sodium-sulfur electrolysis cell, and the sodium sulfide is converted into sodium and sulfur under the action of electric current; the sodium produced in the sodium-sulfur electrolysis cell is passed through the sodium desulfurization device; the lithium nitride is passed through the lithium-nitrogen electrolysis cell, and the lithium nitride is converted into lithium and nitrogen under the action of electric current; the lithium produced in the lithium-nitrogen electrolysis cell is passed through the lithium denitrification device; S2: Classification processing The decontaminated and upgraded oil is passed into a flash tank to generate light hydrocarbons below C5, naphtha, and distillate oil; the light hydrocarbons below C5 and naphtha are passed into the light hydrocarbon recovery unit to separate the light hydrocarbons below C5 and naphtha; the naphtha separated by the light hydrocarbon recovery unit is passed into the catalytic reforming unit to produce reformed hydrogen, reformed dry gas, reformed liquefied gas, reformed C5, and reformed gasoline; the distillate oil is passed into the ebullated bed hydrocracking unit to produce acid gas, dry gas, liquefied gas, light naphtha, heavy naphtha, diesel, wax oil, and residual oil; the acid gas is passed into the alkali neutralization unit of the impurity removal process; S3: Product refining process The reformed gasoline is introduced into the aromatics extraction unit to generate BTX, raffinate and C9+ aromatics; the light hydrocarbons below C5, the reformed C5, the light naphtha and the raffinate are introduced into the ethylene cracking unit to generate hydrogen, ethylene, propylene, C4 fraction, ethylene gasoline and ethylene tar; the ethylene gasoline is introduced into the pyrolysis gasoline hydrogenation unit to obtain hydrogenated gasoline, and the hydrogenated gasoline is introduced into the aromatics extraction unit; the diesel produced in the ebullated bed hydrocracking unit, the wax oil and the C9+ aromatics produced in the aromatics extraction unit are introduced into the hydrocracking unit, the light naphtha and hydrogenated tail oil produced by the hydrocracking unit are introduced into the ethylene cracking unit, and the heavy naphtha produced by the hydrocracking unit is introduced into the catalytic reforming unit; the residual oil produced in the ebullated bed hydrocracking unit and the ethylene tar produced by the ethylene cracking unit are introduced into the heating furnace.

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