Method and system for preparing carbon material raw material through segmented hydrogenation

Abstract

The invention discloses a method and a system for preparing a carbon raw material through segmented hydrogenation. The method comprises the following steps: carrying out solvent deasphalting on heavy oil to obtain deasphalted oil, carrying out reduced pressure distillation on the deasphalted oil, then carrying out selective hydrotreating on middle distillate oil subjected to the reduced pressure distillation, and carrying out hydrogenation ring-opening treatment on heavy distillate oil subjected to the reduced pressure distillation, and then carrying out gas-liquid separation on the product after the selective hydrotreating treatment and the product after the hydrogenation ring-opening treatment to obtain a liquid phase which is a carbon material raw material. The carbon material raw material prepared by the method has high yield, high content of tricyclic aromatic hydrocarbon and tetracyclic aromatic hydrocarbon and low impurity content, and can be used for preparing high-quality carbon materials, such as needle coke and / or mesophase pitch and the like.

Description

A method and system for preparing carbon material raw materials by staged hydrogenation Technical Field

[0001] This invention relates to the field of carbon materials technology, and specifically to a method and system for preparing carbon material raw materials by staged hydrogenation. Background Technology

[0002] In recent years, with the development of ultra-high power electric arc furnace steelmaking technology, the demand for high-power and ultra-high power graphite electrodes has increased significantly. Needle coke, with its advantages of low resistivity, small coefficient of thermal expansion, strong impact resistance, high mechanical strength, and good oxidation resistance, has become an ideal raw material for high-power and ultra-high power electrodes. Furthermore, with the development of new energy technologies, the demand for carbon materials for battery anodes is strong and has high added value.

[0003] Furthermore, mesophase pitch is a pitch-like mixture composed of polycyclic aromatic hydrocarbons and heterocyclic aromatic hydrocarbons with a relative molecular mass of 400–4000, possessing a certain degree of planarity and regular arrangement. It exhibits both crystalline optical anisotropy and exists in a fluid state. The materials for preparing mesophase pitch are widely available and inexpensive, making it an excellent precursor for the preparation of high-performance carbon materials such as carbon fibers, carbon foam, C / C composites, high thermal conductivity carbon, and carbon electrodes. Carbon fibers, in particular, possess characteristics such as high modulus, high strength, good thermal conductivity, good heat resistance, and corrosion resistance, and can be used in aircraft material manufacturing, rail design, and are also widely used in the production of golf clubs, tennis rackets, fishing gear, and other materials. Currently, the production scale of mesophase pitch remains low, especially achieving a complete production line of thousands of tons of mesophase pitch, which is extremely difficult. It is necessary to solve the current problem of not being able to continuously produce high-purity mesophase pitch, thus hindering the reduction of large-scale production costs. Moreover, how to further improve the quality of mesophase pitch is a topic that requires further research in this field.

[0004] Heavy crude oil rich in aromatics, catalytic slurry oil from secondary processed oils, and ethylene tar are theoretically ideal raw materials for the production of carbon materials. However, due to the high content of polycyclic aromatic hydrocarbons and impurities such as sulfur, nitrogen, metals, and ash in these raw materials, there is currently a lack of representative and efficient processing and utilization technologies.

[0005] In crude oil processing, the main technologies for heavy oil conversion include catalytic cracking, hydrocracking, and coking. Heavy oil hydrotreating is a process technology that simultaneously meets the requirements of efficient heavy oil utilization and environmental protection. To date, four process types have been developed for heavy oil hydrotreating: fixed bed, fluidized bed, slurry bed, and moving bed. Among these four types, the fixed bed process is mature, easy to operate, and has relatively low investment costs, making it the most widely used. The main reactions occurring during heavy oil hydrotreating include hydrodemetallization, hydrodesulfurization, hydronitrogenation, residual carbon conversion, and hydrocracking of asphaltenes.

[0006] CN103184057A, CN104560152A and other publications disclose methods for producing needle coke using catalytic oil slurry as raw material. However, needle coke has high requirements for raw materials, and not all components in catalytic oil slurry can be used to produce needle coke.

[0007] CN1872963A discloses a method for producing needle coke feedstock, which enriches tricyclic and tetracyclic aromatic hydrocarbons in catalytic oil slurry as feedstock for producing needle coke, but the remaining components are still not well utilized.

[0008] CN101250433A discloses a coal tar hydrogenation process. Coal tar is pretreated to obtain coal tar hydrogenation feedstock, which then passes through a series of upflow pre-hydrogenation fixed-bed reactors and downflow main hydrogenation fixed-bed reactors. The process involves fractionation to obtain gasoline, diesel, and light fuel oil fractions. The purpose of this process is to produce fuel oil, but the gas-liquid mass transfer in the reaction system is poor, and the investment is high.

[0009] CN103789028A discloses a pretreatment method for producing needle coke feedstock from catalytic oil slurry, comprising: filtering the catalytic oil slurry and then subjecting it to mild hydrogenation treatment; sending 20% ​​to 50% (by weight) of the hydrogenated oil to a vacuum distillation unit; and mixing the resulting hydrogenated light distillate with the remaining hydrogenated oil as feedstock for needle coke production. However, this method has poor feedstock adaptability, low oil slurry yield, and low utilization rate.

[0010] CN117683562A discloses a method and system for preparing feedstock for needle coke production. The method includes: mixing feedstock oil and an oil-soluble hydrogenation catalyst to obtain feed oil; then feeding the feed oil into a slurry-bed hydrogenation reactor to contact with hydrogen and selectively hydrogenate it to obtain a hydrogenated product; subjecting the hydrogenated product to a first separation to obtain a first separation product and a second separation product; the first separation product contains naphtha, hydrogen, and light oil gas; the second separation product contains heavy oil slurry and an oil-soluble hydrogenation catalyst; subjecting the second separation product to vacuum distillation to obtain atmospheric distillate oil, vacuum distillate oil, and recycled tail oil; returning the recycled tail oil and mixing it with the feedstock oil and the oil-soluble hydrogenation catalyst for reuse. This method reduces the impurity content in the vacuum distillate oil and increases the content of tricyclic and tetracyclic aromatics. However, this method has drawbacks such as low impurity removal rate, high conversion rate, low yield of effective carbon materials, and low quality of the produced carbon materials.

[0011] Therefore, how to further improve the adaptability of carbon material raw materials and improve the quality of carbon materials such as needle coke and mesophase pitch are topics that need further research in this field. Summary of the Invention

[0012] To address the aforementioned technical problems, the present invention aims to provide a method and system for preparing carbon material raw materials through staged hydrogenation. The carbon material raw materials prepared by this invention exhibit high yield, high content of tricyclic and tetracyclic aromatic hydrocarbons, and low impurity content, making them suitable for preparing high-quality carbon materials.

[0013] To achieve the above objectives, a first aspect of the present invention provides a method for preparing carbon material raw materials by staged hydrogenation, comprising the following steps:

[0014] (1) Solvent deasphalting of heavy oil yields asphalt and deasphalted oil;

[0015] (2) The deasphalted oil obtained in step (1) is subjected to vacuum distillation to obtain light distillate, middle distillate and heavy distillate;

[0016] (3) Selectively hydrogenate the middle distillate oil obtained in step (2) to obtain the product after selective hydrogenation.

[0017] (4) The heavy distillate oil obtained in step (2) is subjected to hydroring-ring-opening treatment to obtain the product after hydroring-ring-opening treatment;

[0018] (5) The product obtained after selective hydrogenation treatment in step (3) and the product obtained after hydrogenation ring-opening treatment in step (4) are separated by gas and liquid. The resulting liquid phase is the carbon material raw material.

[0019] According to a specific embodiment of the present invention, preferably, in step (1), based on the total mass of the heavy oil as 100%, the sulfur content of the heavy oil is 0.5-5.0%, the asphaltene content is 1-20%, the effective aromatic hydrocarbon content is 15-40%; and the nitrogen content of the heavy oil is 1000-10000 μg / g, and the ash content is 800-7000 ppm.

[0020] According to a specific embodiment of the present invention, preferably, in step (1), the solvent deasphalting is carried out using an extraction tower, and the conditions for solvent deasphalting include: extraction pressure of 1-8 MPa, extraction temperature of 50-300℃, solvents including alkanes, etc., and the mass ratio of solvent to heavy oil of (0.5-5):1.

[0021] According to a specific embodiment of the present invention, preferably, in step (1), based on the total mass of the deasphalted oil as 100%, the sulfur content of the deasphalted oil is 0.6-4.5%, the asphaltene content is 0.1-3.0%, and the effective aromatic hydrocarbon content is 25-45%; and the nitrogen content of the deasphalted oil is 800-6000 μg / g, and the ash content is below 100 ppm.

[0022] According to a specific embodiment of the present invention, preferably, in step (2), the 10% distillation point temperature of the light distillate oil is 160-260℃, and the 90% distillation point is 300-400℃; the 10% distillation point of the middle distillate oil is 310-390℃, and the 90% distillation point is 400-550℃; the 10% distillation point of the heavy distillate oil is 460-560℃. More preferably, the 10% distillation point temperature of the light distillate oil is 180-240℃, and the 90% distillation point is 320-360℃; the 10% distillation point of the middle distillate oil is 310-370℃, and the 90% distillation point is 460-500℃; the 10% distillation point of the heavy distillate oil is 470-500℃.

[0023] According to a specific embodiment of the present invention, preferably, in step (3), the conditions for the selective hydrogenation treatment include: a hydrogen partial pressure of 1.0-20.0 MPa, a temperature of 280-500 °C, and a volume hourly space velocity of 0.5-2.0 h⁻¹. -1 The hydrogen-to-oil ratio is 200-1000. More preferably, the conditions for the selective hydrotreating include: a hydrogen partial pressure of 2.0-8.0 MPa, a temperature of 300-450°C, and a volume hourly space velocity of 0.6-1.2 h⁻¹. -1 The hydrogen-to-oil ratio is 300-800.

[0024] According to a specific embodiment of the present invention, preferably, in step (4), the conditions for the hydrogenation ring-opening treatment include: a hydrogen partial pressure of 5.0-35.0 MPa, a temperature of 300-500 °C, and a volume hourly space velocity of 0.1-1.0 h⁻¹. -1 The hydrogen-to-oil ratio is 200-1500. More preferably, the conditions for the hydrogenation ring-opening treatment include: a hydrogen partial pressure of 8.0-20.0 MPa, a temperature of 350-450 °C, and a volume hourly space velocity of 0.2-0.8 h⁻¹. -1 The hydrogen-to-oil ratio is 400-1000.

[0025] According to a specific embodiment of the present invention, preferably, in step (5), based on the total mass of the carbon material raw material as 100%, the effective aromatic hydrocarbon content of the carbon material raw material is 30-55%, the sulfur content is 0.10-0.50%, and the nitrogen content of the carbon material raw material is 200-2000 μg / g.

[0026] A second aspect of the present invention provides a system for the staged hydrogenation preparation of carbon material raw materials. The system is used to implement the aforementioned method for staged hydrogenation preparation of carbon material raw materials. The system includes: a solvent deasphalting unit, a vacuum distillation unit, a selective hydrogenation reactor, a hydrogenation ring-opening reactor, and a gas-liquid separation unit. The deasphalted oil outlet of the solvent deasphalting unit is connected to the vacuum distillation unit. The vacuum distillation unit is provided with a light distillate oil outlet, a middle distillate oil outlet, and a heavy distillate oil outlet. The middle distillate oil outlet is connected to the selective hydrogenation reactor, the heavy distillate oil outlet is connected to the hydrogenation ring-opening reactor, and the selective hydrogenation reactor and the hydrogenation ring-opening reactor are connected to the gas-liquid separation unit.

[0027] According to a specific embodiment of the present invention, preferably, the solvent deasphalting device includes an extraction tower, etc.

[0028] According to a specific embodiment of the present invention, preferably, the vacuum distillation apparatus includes one or two of the following: a stripping tower and a fractionating tower.

[0029] According to a specific embodiment of the present invention, preferably, the selective hydrogenation reactor and the hydrogenation ring-opening reactor respectively include one or more of the following: a fixed bed reactor, a suspended bed reactor, a fluidized bed reactor, and a moving bed reactor.

[0030] The present invention has at least the following beneficial effects:

[0031] This invention first deasphalts heavy oil to obtain deasphalted oil, then performs vacuum distillation on the deasphalted oil, followed by selective hydrogenation and hydrogenation ring-opening treatment on the separated middle distillate and heavy distillate oils, respectively. Performing hydrogenation treatment separately for different fractions increases the flexibility of this invention, improves the adaptability of heavy oil feedstocks, and increases the yield of carbon material feedstocks. Furthermore, this invention fully utilizes the heavy distillate oil, deeply removing impurities such as sulfur and nitrogen while simultaneously increasing the yield of carbon material feedstocks and the content of tricyclic and tetracyclic aromatic hydrocarbons through polycyclic aromatic hydrocarbon cracking. Subsequently, the products after selective hydrogenation and hydrogenation ring-opening treatments are separated into gas and liquid phases, with the resulting liquid phase serving as the carbon material feedstock. This method broadens the range of feedstocks for preparing high-quality carbon materials, efficiently removing impurities from heavy oil while inhibiting oversaturation of aromatic hydrocarbons and increasing the content of tricyclic and tetracyclic aromatic hydrocarbons, while simultaneously reducing costs. The carbon material raw materials prepared by this invention have high yields, high contents of tricyclic and tetracyclic aromatic hydrocarbons, and low impurity content. They can be used to prepare high-quality carbon materials, such as needle coke and / or mesophase pitch. Furthermore, the needle coke and mesophase pitch prepared from the carbon material raw materials of this invention have high quality, and in particular, can co-produce high-quality needle coke and mesophase pitch. Attached Figure Description

[0032] Figure 1 is a schematic diagram of the method and system for preparing carbon material raw materials by segmented hydrogenation in a specific embodiment of the present invention.

[0033] Explanation of icon numbers:

[0034] 1- Solvent deasphalting unit; 2- Vacuum distillation unit; 3- Selective hydrogenation reactor; 4- Hydrogenation ring-opening reactor; 5- Gas-liquid separation unit. Detailed Implementation

[0035] To provide a clearer understanding of the technical features, objectives, and beneficial effects of the present invention, the present invention will now be described in detail below, but this should not be construed as limiting the scope of the invention.

[0036] It should be noted that, unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0037] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0038] In the description of this invention, it should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Unless otherwise expressly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0039] According to a specific embodiment of the first aspect of the present invention, as shown in FIG1, the present invention provides a method for preparing carbon material raw materials by staged hydrogenation, which includes the following steps:

[0040] (1) Heavy oil is deasphalted in solvent deasphalting unit 1 to obtain asphalt and deasphalted oil;

[0041] (2) The deasphalted oil obtained in step (1) is subjected to vacuum distillation in vacuum distillation apparatus 2 to obtain light distillate oil, middle distillate oil and heavy distillate oil;

[0042] (3) The middle distillate oil obtained in step (2) is selectively hydrogenated in the selective hydrogenation reactor 3 to obtain the product after selective hydrogenation.

[0043] (4) The heavy distillate oil obtained in step (2) is subjected to hydroring-ring-opening treatment in hydroring-opening treatment reactor 4 to obtain the hydroring-ring-opening product.

[0044] (5) The product obtained in step (3) after selective hydrogenation treatment and the product obtained in step (4) after hydrogenation ring-opening treatment are separated by gas-liquid separation device 5, and the resulting liquid phase is the carbon material raw material.

[0045] In some embodiments, in step (1), based on the total mass of the heavy oil as 100%, the heavy oil has a sulfur content of 0.5-5.0%, an asphaltene content of 1-20%, and an effective aromatic hydrocarbon content of 15-40%; and the heavy oil has a nitrogen content of 1000-10000 μg / g and an ash content of 800-7000 ppm. Specifically, the heavy oil may include one or more of the following: catalytic slurry oil, residual oil, furfural extract oil, ethylene tar, coal tar, and coal-based soft pitch. This invention has a wide adaptability to heavy oil feedstocks, and can use petroleum-based feedstocks, coal-based feedstocks, or a mixture of one or more of petroleum-based and coal-based feedstocks. Those skilled in the art will understand that ash refers to the non-flammable substances remaining after the oil has been calcined at high temperatures, and is generally inorganic.

[0046] In this invention, effective aromatic hydrocarbons refer to tricyclic aromatic hydrocarbons and tetracyclic aromatic hydrocarbons.

[0047] In some embodiments, in step (1), the solvent deasphalting is carried out using an extraction tower. The conditions for solvent deasphalting include: an extraction pressure of 1-8 MPa (preferably 2-6 MPa), an extraction temperature of 50-300°C, and the solvent used includes alkanes, etc., with a solvent-to-heavy oil mass ratio of (0.5-5):1 (preferably (2-5):1). Specifically, the solvent used may include one or more of propane, n-butane, n-heptane, n-pentane, n-hexane, isohexane, cyclohexane, n-heptane, isoheptane, neoheptane, n-octane, and isooctane.

[0048] In some embodiments, in step (1), based on the total mass of the deasphalted oil as 100%, the sulfur content of the deasphalted oil is 0.6-4.5%, the asphaltene content is 0.1-3.0%, the effective aromatic hydrocarbon content is 25-45%; and the nitrogen content of the deasphalted oil is 800-6000 μg / g, and the ash content is below 100 ppm.

[0049] In some embodiments, in step (2), the 10% distillation point temperature of the light distillate oil is 160-260℃, and the 90% distillation point is 300-400℃; the 10% distillation point of the middle distillate oil is 310-390℃, and the 90% distillation point is 400-550℃; the 10% distillation point of the heavy distillate oil is 460-560℃. Preferably, the 10% distillation point temperature of the light distillate oil is 180-240℃, and the 90% distillation point is 320-360℃; the 10% distillation point of the middle distillate oil is 310-370℃, and the 90% distillation point is 460-500℃; the 10% distillation point of the heavy distillate oil is 470-500℃.

[0050] In some embodiments, in step (3), the conditions for the selective hydrogenation treatment include: a hydrogen partial pressure of 1.0-20.0 MPa, a temperature of 280-500 °C, and a volume hourly space velocity of 0.5-2.0 h⁻¹. -1 The hydrogen-to-oil ratio is 200-1000. Preferably, the conditions for the selective hydrotreating include: a hydrogen partial pressure of 2.0-8.0 MPa, a temperature of 300-450°C, and a volume hourly space velocity of 0.6-1.2 h⁻¹. -1 The hydrogen-to-oil ratio is 300-800.

[0051] In some embodiments, in step (4), the conditions for the hydrogenation ring-opening treatment include: a hydrogen partial pressure of 5.0-35.0 MPa, a temperature of 300-500 °C, and a volume hourly space velocity of 0.1-1.0 h⁻¹. -1The hydrogen-to-oil ratio is 200-1500. Preferably, the conditions for the hydrogenation ring-opening treatment include: a hydrogen partial pressure of 8.0-20.0 MPa, a temperature of 350-450°C, and a volume hourly space velocity of 0.2-0.8 h⁻¹. -1 The hydrogen-to-oil ratio is 400-1000.

[0052] In embodiments of the present invention, both the selective hydrogenation treatment and the hydrogenation ring-opening treatment require the use of a hydrogenation catalyst. The present invention does not impose special limitations on the hydrogenation catalyst and can employ hydrogenation catalysts from the prior art. For example, the hydrogenation catalyst used may include one or more catalysts selected from hydrogenation protectants, hydrogenation desulfurization catalysts, hydrogenation denitrogenation catalysts, hydrogenation demetallization catalysts, and hydrogenation ring-opening catalysts, or a combination of two or more such catalysts. Generally, the hydrogenation catalyst includes a support and a metal oxide active component supported on the support. The support may include one or more porous, refractory compounds, such as alumina, clay, and molecular sieves; or the support may also be a porous, refractory compound containing one or more elements such as P, Si, F, and B. The metal oxide active component may include one or more metal oxides selected from Group VIB and Group VIII metals, such as one or more metal oxides selected from W, Mo, Co, and Ni.

[0053] In some preferred embodiments, the selective hydrogenation treatment uses a hydrogenation catalyst comprising a hydrogenation protectant and a hydrogenation desulfurizer, and selectively includes one or both of a hydrogenation denitrification agent and a hydrogenation demetallization agent; the hydrogenation ring-opening treatment uses a hydrogenation catalyst comprising a hydrogenation demetallization agent and a hydrogenation ring-opening catalyst, and selectively includes a hydrogenation protectant and / or a hydrogenation denitrification agent. Specifically, the selective hydrogenation treatment uses a hydrogenation catalyst comprising a hydrogenation protectant and a hydrogenation desulfurizer loaded sequentially along the stream direction, or comprising a hydrogenation protectant, a hydrogenation desulfurizer, and a hydrogenation denitrification agent loaded sequentially along the stream direction, or comprising a hydrogenation protectant, a hydrogenation demetallization agent, and a hydrogenation desulfurizer loaded sequentially along the stream direction. The hydrogenation catalyst used in the hydrogenation ring-opening treatment includes a hydrogenation demetallizing agent and a hydrogenation ring-opening catalyst loaded sequentially along the stream flow direction, or includes a hydrogenation protective agent, a hydrogenation demetallizing agent and a hydrogenation ring-opening catalyst loaded sequentially along the stream flow direction, or includes a hydrogenation protective agent, a hydrogenation demetallizing agent, a hydrogenation denitrifying agent and a hydrogenation ring-opening catalyst loaded sequentially along the stream flow direction.

[0054] In some embodiments, in step (5), based on the total mass of the carbon material raw material as 100%, the effective aromatic hydrocarbon content of the carbon material raw material is 30-55%, the sulfur content is 0.10-0.50%, and the nitrogen content of the carbon material raw material is 200-2000 μg / g.

[0055] According to a specific embodiment of the second aspect of the present invention, the present invention provides a system for preparing carbon material raw materials by segmented hydrogenation. The system is used to implement the above-mentioned method for preparing carbon material raw materials by segmented hydrogenation. As shown in FIG1, the system includes: a solvent deasphalting device 1, a vacuum distillation device 2, a selective hydrogenation treatment reactor 3, a hydrogenation ring-opening treatment reactor 4, and a gas-liquid separation device 5.

[0056] Among them, the solvent deasphalting unit 1 is equipped with at least a raw material inlet, a solvent inlet, an asphalt outlet and a deasphalted oil outlet; the vacuum distillation unit 2 is equipped with at least an inlet, a light distillate oil outlet, a middle distillate oil outlet and a heavy distillate oil outlet; the selective hydrogenation treatment reactor 3 is equipped with at least a raw material inlet, a hydrogen inlet and a product outlet; the hydrogenation ring-opening treatment reactor 4 is equipped with at least a raw material inlet, a hydrogen inlet and a product outlet; and the gas-liquid separation unit 5 is equipped with at least an inlet, a gas phase outlet and a liquid phase outlet.

[0057] The deasphalted oil outlet of solvent deasphalting unit 1 is connected to the inlet of vacuum distillation unit 2. The middle distillate oil outlet of vacuum distillation unit 2 is connected to the feed inlet of selective hydrotreating reactor 3. The heavy distillate oil outlet of vacuum distillation unit 2 is connected to the feed inlet of hydrotreating open-loop treatment reactor 4. The product outlets of selective hydrotreating reactor 3 and hydrotreating open-loop treatment reactor 4 are connected to the inlet of gas-liquid separation unit 5. The carbon material feedstock flows out of the liquid phase outlet of gas-liquid separation unit 5.

[0058] In some embodiments, the solvent deasphalting apparatus 1 includes an extraction tower, etc.

[0059] In some embodiments, the vacuum distillation apparatus 2 includes one or both of the following: a stripping column and a fractionating column.

[0060] In some embodiments, the selective hydrogenation reactor 3 and the hydrogenation ring-opening reactor 4 each include one or more of the following: a fixed-bed reactor, a suspended-bed reactor, a fluidized-bed reactor, and a moving-bed reactor, with a fixed-bed reactor being preferred. Specifically, the selective hydrogenation reactor 3 and the hydrogenation ring-opening reactor 4 may each include one reactor or multiple reactors connected in series.

[0061] In some embodiments, the gas-liquid separation device 5 may specifically include one or two of a high-pressure gas-liquid separator and a low-pressure gas-liquid separator.

[0062] In the embodiments of the present invention, after the carbon material raw material is prepared by the above method and system, the carbon material can then be prepared by the process in the prior art. The carbon material includes needle coke and / or mesophase pitch, etc.

[0063] In some embodiments, the preparation of needle coke using the carbon material raw material of the present invention involves reacting the carbon material raw material in a coking reaction zone to obtain needle coke. The coking reaction zone generally includes at least one heating furnace and at least two coke towers, and at least one coke tower is always in the reaction stage and at least one coke tower is in the decoking stage. The reaction conditions in the coking reaction zone may include: a heating furnace outlet temperature of 410-550°C, preferably 440-520°C; a heating rate of 0.5-30°C / h, preferably 3-8°C / h; a tower top pressure of 0.01-2.5 MPa, preferably 0.2-1.3 MPa; the coke tower can operate under constant pressure or variable pressure; when operating under variable pressure, the variable pressure rate is 0.1-5 MPa / h; and the reaction cycle of the coking reaction zone is 10-72 hours, preferably 32-54 hours. The specific devices in the coking reaction zone can be those commonly used in the art, and those skilled in the art can select or adjust them according to actual conditions.

[0064] In other embodiments, the preparation of mesophase pitch using the carbon material raw material of the present invention involves sequentially subjecting the carbon material raw material to a polymerization reaction and an oxidation reaction to obtain the mesophase pitch. Specifically, the polymerization reaction is carried out at a temperature of 360-440°C, a pressure of 2.0-8.0 MPa, and a time of 1-10 h; the oxidation reaction is carried out at a temperature of 280-330°C, a time of 1-6 h, and an air flow rate of 1-2 L / min. The specific apparatus used for the polymerization and oxidation reactions can be commonly used in the art, and those skilled in the art can select or adjust it according to the actual situation.

[0065] The present invention is illustrated in detail below by way of examples, but the present invention is not limited to these examples. Of course, various modifications can be made within the scope of the present invention.

[0066] The sources of heavy oil feedstock and hydrogenation catalyst used in the following examples and comparative examples are shown in Table 1.

[0067] Table 1. Sources of heavy oil feedstock and hydrotreating catalysts

[0068] Serial Number | Heavy Oil Feedstock Source / Model | 1 | Catalytic Slurry | Daqing Petrochemical Catalytic Cracking Unit | 2 | Vacuum Residue | Daqing Petrochemical Atmospheric and Vacuum Distillation Unit | 3 | Furfural Extracted Oil | Daqing Petrochemical Furfural Extraction Unit | 4 | Ethylene Tar | Daqing Petrochemical Ethylene Cracking Unit | 5 | Coal Tar | Purchased from the Market | 6 | Hydrotreating Protective Agent | Fushun Catalyst Plant PHR-405 | 7 | Hydrotreating Demetallizing Agent | Fushun Catalyst Plant PHR-101 | 8 | Hydrotreating Desulfurizing Agent | Fushun Catalyst Plant PHR-202 | 9 | Hydrotreating Denitrogenating Agent | Fushun Catalyst Plant PHR-305 | 10 | Hydrotreating Ring-Opening Catalyst | Fushun Catalyst Plant PHR-306 surface

[0069] Example 1

[0070] This embodiment provides a method for preparing carbon material raw materials by staged hydrogenation, which includes the following steps:

[0071] (1) Heavy oil is deasphalted in solvent deasphalting unit 1 to obtain asphalt and deasphalted oil;

[0072] (2) The deasphalted oil obtained in step (1) is subjected to vacuum distillation in vacuum distillation apparatus 2 to obtain light distillate oil, middle distillate oil and heavy distillate oil;

[0073] (3) The middle distillate oil obtained in step (2) is selectively hydrogenated in the selective hydrogenation reactor 3 to obtain the product after selective hydrogenation.

[0074] (4) The heavy distillate oil obtained in step (2) is subjected to hydroring-ring-opening treatment in hydroring-opening treatment reactor 4 to obtain the hydroring-ring-opening product.

[0075] (5) The product obtained in step (3) after selective hydrogenation treatment and the product obtained in step (4) after hydrogenation ring-opening treatment are separated by gas-liquid separation device 5, and the resulting liquid phase is the carbon material raw material.

[0076] The main properties of the heavy oil used in this embodiment are shown in Table 2.

[0077] In this embodiment, in step (1), solvent deasphalting is carried out using an extraction tower. The conditions for solvent deasphalting include: extraction pressure of 4.0 MPa, extraction temperature of 120°C, solvent used as n-butane, and solvent to heavy oil mass ratio of 4:1. In step (1), based on the total mass of the deasphalted oil as 100%, the sulfur content of the deasphalted oil is 3.85%, the asphaltene content is 0.8%, and the effective aromatic hydrocarbon content is 28.4%; and the nitrogen content of the deasphalted oil is 2230 μg / g, and the ash content is 90 ppm. In step (2), the 10% distillation point temperature of the light distillate oil is 187°C, and the 90% distillation point is 326°C; the 10% distillation point of the middle distillate oil is 318°C, and the 90% distillation point is 465°C; the 10% distillation point of the heavy distillate oil is 479°C. In step (3), the conditions for the selective hydrogenation treatment are shown in Table 3. In step (4), the conditions for the hydrogenation ring-opening treatment are shown in Table 4.

[0078] In this embodiment, the solvent deasphalting unit 1 includes an extraction tower. The vacuum distillation unit 2 is a fractionation tower. The selective hydrogenation reactor 3 and the hydrogenation ring-opening reactor 4 are both fixed-bed reactors.

[0079] The selective hydrotreating reactor 3 consists of a fixed-bed reactor, specifically a trickle-bed reactor, which is loaded sequentially along the stream direction with a volume ratio of 20:60:20 for hydroprotective agent PHR-405, hydrodesulfurizing agent PHR-202, and hydrodenitrifying agent PHR-305. The hydroring-opening reactor 4 consists of two fixed-bed reactors, specifically two trickle-bed reactors connected in series, which are loaded along the stream direction with a volume ratio of 15:15:30:40 for hydroprotective agent PHR-405, hydrodemetallizing agent PHR-101, hydrodenitrifying agent PHR-305, and hydroring-opening catalyst PHR-306.

[0080] The main properties of the carbon material raw materials prepared in this embodiment are shown in Table 5.

[0081] Example 2

[0082] This embodiment provides a method for preparing carbon material raw materials by staged hydrogenation, which includes the same steps as the method in Embodiment 1.

[0083] The main properties of the heavy oil used in this embodiment are shown in Table 2.

[0084] In this embodiment, in step (1), solvent deasphalting is carried out using an extraction tower. The conditions for solvent deasphalting include: extraction pressure of 5 MPa, extraction temperature of 180°C, solvent used as n-pentane, and solvent to heavy oil mass ratio of 2:1. In step (1), based on the total mass of the deasphalted oil as 100%, the sulfur content of the deasphalted oil is 1.96%, the asphaltene content is 1.70%, and the effective aromatic hydrocarbon content is 35.8%; and the nitrogen content of the deasphalted oil is 1710 μg / g, and the ash content is 85 ppm. In step (2), the 10% distillation point temperature of the light distillate oil is 205°C, and the 90% distillation point is 335°C; the 10% distillation point of the middle distillate oil is 345°C, and the 90% distillation point is 475°C; the 10% distillation point of the heavy distillate oil is 481°C. In step (3), the conditions for the selective hydrogenation treatment are shown in Table 3. In step (4), the conditions for the hydrogenation ring-opening treatment are shown in Table 4.

[0085] In this embodiment, the solvent deasphalting unit 1 includes an extraction tower. The vacuum distillation unit 2 is a fractionation tower. The selective hydrogenation reactor 3 and the hydrogenation ring-opening reactor 4 are both fixed-bed reactors.

[0086] The selective hydrotreating reactor 3 consists of a fixed-bed reactor, specifically a trickle-bed reactor, and is sequentially loaded along the stream direction with a 50:50 volume ratio of hydroprotectant PHR-405 and hydrodesulfurizing agent PHR-202. The hydroring-opening reactor 4 also consists of a fixed-bed reactor, specifically a trickle-bed reactor, and is loaded along the stream direction with a 15:15:30:40 volume ratio of hydroprotectant PHR-405, hydrodemetallizing agent PHR-101, hydrodenitrifying agent PHR-305, and hydroring-opening catalyst PHR-306.

[0087] The main properties of the carbon material raw materials prepared in this embodiment are shown in Table 5.

[0088] Example 3

[0089] This embodiment provides a method for preparing carbon material raw materials by staged hydrogenation, which includes the same steps as the method in Embodiment 1.

[0090] The main properties of the heavy oil used in this embodiment are shown in Table 2.

[0091] In this embodiment, in step (1), solvent deasphalting is carried out using an extraction tower. The conditions for solvent deasphalting include: extraction pressure of 6 MPa, extraction temperature of 90°C, and the solvent used is a mixed solvent formed by mixing n-butane and n-propane in a 1:1 mass ratio, with a solvent-to-heavy oil mass ratio of 5:1. In step (1), based on the total mass of the deasphalted oil as 100%, the sulfur content of the deasphalted oil is 1.98%, the asphaltene content is 1.21%, and the effective aromatic hydrocarbon content is 34.1%; and the nitrogen content of the deasphalted oil is 1780 μg / g, and the ash content is 95 ppm. In step (2), the 10% distillation point temperature of the light distillate oil is 232°C, and the 90% distillation point is 345°C; the 10% distillation point of the middle distillate oil is 351°C, and the 90% distillation point is 493°C; the 10% distillation point of the heavy distillate oil is 495°C. In step (3), the conditions for the selective hydrogenation treatment are shown in Table 3. In step (4), the conditions for the hydrogenation ring-opening treatment are shown in Table 4.

[0092] In this embodiment, the solvent deasphalting unit 1 includes an extraction tower. The vacuum distillation unit 2 is a fractionation tower. The selective hydrogenation reactor 3 and the hydrogenation ring-opening reactor 4 are both fixed-bed reactors.

[0093] The selective hydrotreating reactor 3 consists of a fixed-bed reactor, specifically a trickle-bed reactor, with hydroprotective agent PHR-405 and hydrodesulfurizing agent PHR-202 loaded sequentially along the stream direction at a volume ratio of 30:70. The hydroring-opening reactor 4 consists of two fixed-bed reactors, specifically two trickle-bed reactors connected in series, with hydroprotective agent PHR-405, hydrodemetallizing agent PHR-101, hydrodenitrifying agent PHR-305, and hydroring-opening catalyst PHR-306 loaded along the stream direction at a volume ratio of 15:15:30:40.

[0094] The main properties of the carbon material raw materials prepared in this embodiment are shown in Table 5.

[0095] Example 4

[0096] This embodiment provides a method for preparing carbon material raw materials by staged hydrogenation, which includes the same steps as the method in Embodiment 1.

[0097] The main properties of the heavy oil used in this embodiment are shown in Table 2.

[0098] In this embodiment, in step (1), solvent deasphalting is carried out using an extraction tower. The conditions for solvent deasphalting include: extraction pressure of 2 MPa, extraction temperature of 80°C, solvent used as n-propane, and solvent-to-heavy oil mass ratio of 5:1. In step (1), based on the total mass of the deasphalted oil as 100%, the sulfur content of the deasphalted oil is 0.65%, the asphaltene content is 2.1%, and the effective aromatic hydrocarbon content is 42.5%; and the nitrogen content of the deasphalted oil is 1350 μg / g, and the ash content is 50 ppm. In step (2), the 10% distillation point temperature of the light distillate oil is 211°C, and the 90% distillation point is 352°C; the 10% distillation point of the middle distillate oil is 361°C, and the 90% distillation point is 496°C; the 10% distillation point of the heavy distillate oil is 485°C. In step (3), the conditions for the selective hydrogenation treatment are shown in Table 3. In step (4), the conditions for the hydrogenation ring-opening treatment are shown in Table 4.

[0099] In this embodiment, the solvent deasphalting unit 1 includes an extraction tower. The vacuum distillation unit 2 is a fractionation tower. The selective hydrogenation reactor 3 and the hydrogenation ring-opening reactor 4 are both fixed-bed reactors.

[0100] The selective hydrotreating reactor 3 consists of a fixed-bed reactor, specifically a trickle-bed reactor, with hydroprotective agent PHR-405 and hydrodesulfurizing agent PHR-202 loaded sequentially along the stream direction at a volume ratio of 30:70. The hydroring-opening reactor 4 consists of two fixed-bed reactors, specifically two trickle-bed reactors connected in series, with hydroprotective agent PHR-405, hydrodemetallizing agent PHR-101, hydrodenitrifying agent PHR-305, and hydroring-opening catalyst PHR-306 loaded along the stream direction at a volume ratio of 15:15:30:40.

[0101] The main properties of the carbon material raw materials prepared in this embodiment are shown in Table 5.

[0102] Example 5

[0103] This embodiment provides a method for preparing carbon material raw materials by staged hydrogenation, which includes the same steps as the method in Embodiment 1.

[0104] The main properties of the heavy oil used in this embodiment are shown in Table 2.

[0105] In this embodiment, in step (1), solvent deasphalting is carried out using an extraction tower. The conditions for solvent deasphalting include: extraction pressure of 8 MPa, extraction temperature of 120°C, solvent of n-hexane, and solvent-to-heavy oil mass ratio of 3.5:1. In step (1), based on the total mass of the deasphalted oil as 100%, the sulfur content of the deasphalted oil is 0.62%, the asphaltene content is 1.1%, and the effective aromatic hydrocarbon content is 41.2%; and the nitrogen content of the deasphalted oil is 1090 μg / g, and the ash content is 30 ppm. In step (2), the 10% distillation point temperature of the light distillate oil is 203°C, and the 90% distillation point is 355°C; the 10% distillation point of the middle distillate oil is 362°C, and the 90% distillation point is 486°C; the 10% distillation point of the heavy distillate oil is 493°C. In step (3), the conditions for the selective hydrogenation treatment are shown in Table 3. In step (4), the conditions for the hydrogenation ring-opening treatment are shown in Table 4.

[0106] In this embodiment, the solvent deasphalting unit 1 includes an extraction tower. The vacuum distillation unit 2 is a fractionation tower. The selective hydrogenation reactor 3 and the hydrogenation ring-opening reactor 4 are both fixed-bed reactors.

[0107] The selective hydrotreating reactor 3 consists of a fixed-bed reactor, specifically a trickle-bed reactor, with hydroprotective agent PHR-405 and hydrodesulfurizing agent PHR-202 loaded sequentially along the stream direction at a volume ratio of 30:70. The hydroring-opening reactor 4 consists of two fixed-bed reactors, specifically two trickle-bed reactors connected in series, with hydroprotective agent PHR-405, hydrodemetallizing agent PHR-101, hydrodenitrifying agent PHR-305, and hydroring-opening catalyst PHR-306 loaded along the stream direction at a volume ratio of 15:15:30:40.

[0108] The main properties of the carbon material raw materials prepared in this embodiment are shown in Table 5.

[0109] Comparative Example 1

[0110] This comparative example provides a method for preparing carbon material raw materials, which includes the following steps:

[0111] (1) Heavy oil is deasphalted in a solvent deasphalting unit to obtain asphalt and deasphalted oil;

[0112] (2) The deasphalted oil obtained in step (1) is subjected to hydroring-ring-opening treatment in a hydroring-ring-opening treatment reactor to obtain the product after hydroring-ring-opening treatment.

[0113] (3) The product obtained after hydrogenation ring-opening treatment in step (2) is separated into gas and liquid phases by a gas-liquid separation device. The resulting liquid phase is the carbon material raw material.

[0114] The heavy oil used in this comparative example is the same as that in Example 1, and its main properties are shown in Table 2.

[0115] In this comparative example, in step (1), the solvent deasphalting was carried out using an extraction tower, and the conditions for solvent deasphalting were the same as in Example 1. In step (2), the conditions for the hydrogenation ring-opening treatment were the same as in Example 1, as shown in Table 4.

[0116] In this comparative example, the solvent deasphalting device is the same as in Example 1. The hydrocracking ring-opening reactor consists of two fixed-bed reactors, specifically two trickle-bed reactors connected in series. Along the stream flow direction, the following components are sequentially loaded in a volume ratio of 15:15:20:20:30: hydroprotectant PHR-405, hydrodemetallizing agent PHR-101, hydrodesulfurizing agent PHR-202, hydrodenitrifying agent PHR-305, and hydrocracking ring-opening catalyst PHR-306. The gas-liquid separation device is the same as in Example 1.

[0117] The main properties of the carbon material raw materials prepared in this comparative example are shown in Table 5.

[0118] Comparative Example 2

[0119] This comparative example provides a method for preparing carbon material raw materials, which includes the following steps:

[0120] (1) Heavy oil is deasphalted in a solvent deasphalting unit to obtain asphalt and deasphalted oil;

[0121] (2) The deasphalted oil obtained in step (1) is subjected to vacuum distillation in a vacuum distillation apparatus to obtain light distillate oil, middle distillate oil and heavy distillate oil;

[0122] (3) The heavy distillate oil obtained in step (2) is subjected to hydroring-ring-opening treatment in a hydroring-ring-opening treatment reactor to obtain the hydroring-ring-opening product.

[0123] (4) The product obtained after hydrogenation ring-opening treatment in step (3) is separated into gas and liquid phases by a gas-liquid separation device, and the resulting liquid phase is the carbon material raw material.

[0124] The main properties of the heavy oil used in this comparative example are shown in Table 2.

[0125] In this comparative example, in step (1), the solvent deasphalting was carried out using an extraction tower, and the conditions for solvent deasphalting were the same as in Example 2. In step (2), the 10% distillation point temperature of the light distillate was 216°C, and the 90% distillation point was 341°C; the 10% distillation point of the middle distillate was 341°C, and the 90% distillation point was 482°C; the 10% distillation point of the heavy distillate was 476°C; all these conditions were similar to those in Example 2. In step (3), the conditions for the hydrogenation ring-opening treatment were the same as those in Example 2, as shown in Table 4.

[0126] In this comparative example, the solvent deasphalting apparatus is the same as in Example 2. The vacuum distillation apparatus is the same as in Example 2. The hydrogenation ring-opening reactor and the hydrogenation catalyst packed therein are the same as in Example 2. The gas-liquid separation apparatus is the same as in Example 2.

[0127] The main properties of the carbon material raw materials prepared in this comparative example are shown in Table 5.

[0128] Comparative Example 3

[0129] This comparative example provides a method for preparing carbon material raw materials, which includes the following steps:

[0130] (1) Heavy oil is deasphalted in a solvent deasphalting unit to obtain asphalt and deasphalted oil;

[0131] (2) The deasphalted oil obtained in step (1) is subjected to vacuum distillation in a vacuum distillation apparatus to obtain light distillate oil, middle distillate oil and heavy distillate oil;

[0132] (3) The middle distillate oil obtained in step (2) is selectively hydrogenated in a selective hydrogenation reactor to obtain the product after selective hydrogenation.

[0133] (4) The product obtained in step (3) after selective hydrogenation is separated into gas and liquid phases by a gas-liquid separation device. The resulting liquid phase is the carbon material raw material.

[0134] The main properties of the heavy oil used in this comparative example are shown in Table 2.

[0135] In this comparative example, in step (1), the solvent deasphalting was carried out using an extraction tower, and the conditions for solvent deasphalting were the same as in Example 1. In step (2), the 10% distillation point temperature of the light distillate oil was 173°C, and the 90% distillation point was 338°C; the 10% distillation point of the middle distillate oil was 323°C, and the 90% distillation point was 472°C; the 10% distillation point of the heavy distillate oil was 485°C; all these conditions were similar to those in Example 1. In step (3), the conditions for the selective hydrogenation treatment were the same as those in Example 1, as shown in Table 3.

[0136] In this comparative example, the solvent deasphalting apparatus is the same as in Example 1. The vacuum distillation apparatus is the same as in Example 1. The selective hydrogenation reactor and the hydrogenation catalyst packed therein are the same as in Example 1. The gas-liquid separation apparatus is the same as in Example 1.

[0137] The main properties of the carbon material raw materials prepared in this comparative example are shown in Table 5.

[0138] Comparative Example 4

[0139] This comparative example provides a method for using carbon material raw materials, which includes the following steps:

[0140] (1) Heavy oil is deasphalted in a solvent deasphalting unit to obtain asphalt and deasphalted oil;

[0141] (2) The deasphalted oil obtained in step (1) is subjected to vacuum distillation in a vacuum distillation apparatus to obtain light distillate oil, middle distillate oil and heavy distillate oil;

[0142] (3) After mixing the middle distillate oil and heavy distillate oil obtained in step (2), perform hydroring-ring opening treatment in a hydroring-ring opening treatment reactor to obtain the hydroring-ring opening treatment product.

[0143] (4) The product obtained after hydrogenation ring-opening treatment in step (3) is separated into gas and liquid phases by a gas-liquid separation device, and the resulting liquid phase is the carbon material raw material.

[0144] The main properties of the heavy oil used in this comparative example are shown in Table 2.

[0145] In this comparative example, in step (1), the solvent deasphalting was carried out using an extraction tower, and the conditions for solvent deasphalting were the same as in Example 1. In step (2), the 10% distillation point temperature of the light distillate oil was 175°C, and the 90% distillation point was 336°C; the 10% distillation point of the middle distillate oil was 325°C, and the 90% distillation point was 470°C; the 10% distillation point of the heavy distillate oil was 487°C; all these conditions were similar to those in Example 1. In step (3), the conditions for the hydrogenation ring-opening treatment were the same as those in Example 1, as shown in Table 4.

[0146] In this comparative example, the solvent deasphalting apparatus is the same as in Example 1. The vacuum distillation apparatus is the same as in Example 1. The hydrogenation ring-opening reactor and the hydrogenation catalyst packed therein are the same as in Example 1. The gas-liquid separation apparatus is the same as in Example 1.

[0147] The main properties of the carbon material raw materials prepared in this comparative example are shown in Table 5.

[0148] Comparative Example 5

[0149] This comparative example provides a method for using carbon material raw materials, which includes the following steps:

[0150] (1) Heavy oil is deasphalted in a solvent deasphalting unit to obtain asphalt and deasphalted oil;

[0151] (2) The deasphalted oil obtained in step (1) is subjected to vacuum distillation in a vacuum distillation apparatus to obtain light distillate oil, middle distillate oil and heavy distillate oil;

[0152] (3) After mixing the middle distillate oil and heavy distillate oil obtained in step (2), selective hydrogenation is carried out in a selective hydrogenation reactor to obtain the product after selective hydrogenation.

[0153] (4) The product obtained in step (3) after selective hydrogenation is separated into gas and liquid phases by a gas-liquid separation device. The resulting liquid phase is the carbon material raw material.

[0154] The main properties of the heavy oil used in this comparative example are shown in Table 2.

[0155] In this comparative example, in step (1), the solvent deasphalting was carried out using an extraction tower, and the conditions for solvent deasphalting were the same as in Example 1. In step (2), the 10% distillation point temperature of the light distillate oil was 176°C, and the 90% distillation point was 335°C; the 10% distillation point of the middle distillate oil was 320°C, and the 90% distillation point was 468°C; the 10% distillation point of the heavy distillate oil was 483°C; all these conditions were similar to those in Example 1. In step (3), the conditions for the selective hydrogenation treatment were the same as those in Example 1, as shown in Table 3.

[0156] In this comparative example, the solvent deasphalting apparatus is the same as in Example 1. The vacuum distillation apparatus is the same as in Example 1. The selective hydrogenation reactor and the hydrogenation catalyst packed therein are the same as in Example 1. The gas-liquid separation apparatus is the same as in Example 1.

[0157] The main properties of the carbon material raw materials prepared in this comparative example are shown in Table 5.

[0158] Comparative Example 6

[0159] This comparative example provides a method for using carbon material raw materials, which includes the following steps:

[0160] (1) Heavy oil is distilled under reduced pressure in a vacuum distillation apparatus to obtain light distillate, middle distillate and heavy distillate;

[0161] (2) The middle distillate oil obtained in step (1) is selectively hydrogenated in a selective hydrogenation reactor to obtain the product after selective hydrogenation.

[0162] (3) The heavy distillate oil obtained in step (1) is subjected to hydroring-ring-opening treatment in a hydroring-ring-opening treatment reactor to obtain the product after hydroring-ring-opening treatment;

[0163] (4) The product obtained in step (2) after selective hydrogenation treatment and the product obtained in step (3) after hydrogenation ring-opening treatment are separated by a gas-liquid separation device, and the resulting liquid phase is the carbon material raw material.

[0164] The main properties of the heavy oil used in this comparative example are shown in Table 2.

[0165] In this comparative example, in step (1), the 10% distillation point temperature of the light distillate oil is 180°C, and the 90% distillation point is 328°C; the 10% distillation point of the middle distillate oil is 320°C, and the 90% distillation point is 467°C; the 10% distillation point of the heavy distillate oil is 484°C. These conditions are similar to those in Example 1. In step (2), the conditions for the selective hydrotreating are the same as in Example 1, as shown in Table 3. In step (3), the conditions for the hydroring-opening treatment are the same as in Example 1, as shown in Table 4.

[0166] In this comparative example, the vacuum distillation apparatus is the same as in Example 1. The selective hydrogenation reactor and the hydrogenation ring-opening reactor, as well as the hydrogenation catalyst packed therein, are the same as in Example 1. The gas-liquid separation apparatus is the same as in Example 1.

[0167] The main properties of the carbon material raw materials prepared in this comparative example are shown in Table 5.

[0168] Table 2 Main Properties of Heavy Oil

[0169]

[0170] Table 3 Conditions for selective hydrogenation treatment

[0171]

[0172]

[0173] Table 4 Conditions for Hydrogenation Ring-Opening Treatment

[0174]

[0175] Table 5. Product properties and yields of carbon material raw materials

[0176]

[0177] In Table 5, the effective aromatic hydrocarbon content refers to the content of tricyclic and tetracyclic aromatic hydrocarbons, which was tested according to the specifications in SH / T 0659-1998 "Determination of Hydrocarbons in Saturated Hydrocarbon Fractions of Gas Oil (Mass Spectrometry)". The sulfur and nitrogen contents were tested according to the specifications in GB / T 17040-2019 "Determination of Sulfur Content in Petroleum and Petroleum Products - Energy Dispersive X-ray Fluorescence Spectrometry" and SH / T 0657-2007 "Determination of Trace Nitrogen in Liquid Petroleum Hydrocarbons - Oxidation Combustion and Chemiluminescence Methods", respectively. The yield of the carbon material feedstock was calculated as: (Mass of the prepared carbon material feedstock in the 330℃-520℃ distillation range / Mass of the heavy oil feedstock) × 100%.

[0178] The results above show that, within the same operating cycle, compared with Comparative Example 1, Example 1 showed a significant increase in the effective aromatic hydrocarbon content of the carbon material raw material; compared with Comparative Example 2, Example 2 showed a significant increase in the effective aromatic hydrocarbon content of the carbon material raw material, while the S and N contents were significantly reduced; compared with Comparative Examples 3-5, Example 1 showed a significant increase in the effective aromatic hydrocarbon content and / or yield of the carbon material raw material; compared with Comparative Example 6, Example 1 showed a substantial increase in the effective aromatic hydrocarbon content of the carbon material raw material, while the S and N contents were significantly reduced, and Comparative Example 6 could not operate for a long period.

[0179] Application Example 1

[0180] The carbon material raw materials prepared in the above embodiments and comparative examples are respectively fed into the coking reaction zone for reaction. The outlet temperature of the heater in the coking reaction zone is controlled by temperature variation, with a temperature variation range of 460-510℃ and a temperature variation rate of 5℃ / h. The heated material enters the coke tower through pipeline. The pressure at the top of the coke tower is 0.3MPa. The reaction cycle of the coking reaction zone is 38h. After the coking process is completed, the coke tower is purged with steam and decoked to obtain needle coke.

[0181] The needle-shaped raw coke was calcined in a tube furnace at 1300℃ and then ground to a particle size of 0.2-0.8 mm to obtain cooked coke. The cooked coke was then treated in a continuous graphitization furnace at 2800℃ in a nitrogen atmosphere to obtain graphitized specimens.

[0182] The sulfur content, true density, and fiber content in the microstructure of the needle-shaped coke were tested, and the coefficient of thermal expansion of the graphitized specimen was tested. The results are shown in Table 6.

[0183] Table 6. Properties of Needle Coke Products

[0184]

[0185] The coefficient of thermal expansion was determined according to GB / T3074.4 "Determination of Coefficient of Thermal Expansion (CTE) of Graphite Electrodes". The sulfur content was determined according to SH / T0313 "Test Method for Petroleum Coke". The true density was determined according to GB / T6155 "Determination of True Density of Carbon Materials". The method for testing the content of each component in the microstructure includes the following steps: Curing the coke with resin, then grinding and polishing it to create a smooth slide; using a polarizing microscope with crossed polarized light as the light source, observing the microstructure of the slide under an oil immersion lens with a 10x eyepiece and a 50x objective. Microstructures with a unit width of less than 30 μm and a streamlined shape are considered fibers. Multiple fields of view were selected for a sample, and the number of all microstructures (microstructures generally include fibers, regions, and mosaics) in each field of view was observed and counted. The fiber content was calculated as the percentage of fibers in each field of view relative to the total number of microstructures, and the average value of the content across multiple fields of view was taken to obtain the fiber content.

[0186] As shown in Table 6, under the same coking conditions, compared with the needle coke product prepared from the carbon material raw material of Comparative Example 1, the needle coke product prepared from the carbon material raw material of Example 1 of this invention has a significantly lower coefficient of thermal expansion and a significantly higher fiber content. Compared with the needle coke product prepared from the carbon material raw material of Comparative Example 2, the needle coke product prepared from the carbon material raw material of Example 2 of this invention has a significantly lower coefficient of thermal expansion and a significantly higher fiber content. Compared with the needle coke products prepared from the carbon material raw materials of Comparative Examples 3-6, the needle coke product prepared from the carbon material raw material of Example 1 of this invention has a significantly lower coefficient of thermal expansion and a significantly higher fiber content.

[0187] The needle coke products prepared from the carbon material raw materials in each embodiment of the present invention all exhibit high quality and can be used as high-quality raw materials for preparing graphite electrodes and / or anode materials. Furthermore, multiple experiments have shown that the needle coke products prepared from the carbon material raw materials in each embodiment of the present invention exhibit minimal performance fluctuations and high performance stability.

[0188] Application Example 2

[0189] The carbon material raw materials prepared in the above examples and comparative examples were added to a reactor to prepare mesophase pitch: first, the reaction was carried out at 415℃ and 4.0MPa for 5 hours, during which the stirring rate of the reactor was 500 r / min; then, the reactor temperature was lowered to 320℃, and air was introduced at a flow rate of 1.5 L / min, while the stirring rate of the reactor was increased to 120 r / min. After reacting for 2 hours, mesophase pitch was obtained. The properties of the mesophase pitch were tested, and the results are shown in Table 7.

[0190] Table 7 Properties of Mesophase Pitch Products

[0191] Intermediate phase content (%): Example 1 86.5, Example 2 86.8, Example 3 87.2, Example 4 90.3, Example 5 91.6, Comparative Example 1 51.2, Comparative Example 2 31.3, Comparative Example 3 38.6, Comparative Example 4 39.2, Comparative Example 5 36.5, Comparative Example 6 51.3 surface

[0192] The content of the mesophase was determined by observation using a polarizing microscope. Specifically, the mesophase content was obtained by calculating the percentage of the mesophase region area to the total field of view. The mesophase region was determined by optical properties (optical anisotropy) known in the art, and / or texture and morphology (spherical, fibrous, or sheet-like forms with relatively regular texture), and / or by using image analysis software.

[0193] As shown in Table 7, the mesophase pitch products prepared from carbon material raw materials in the various embodiments of the present invention have a high mesophase content, and therefore a high quality. In contrast, the mesophase pitch products prepared from carbon material raw materials in the comparative examples have too low a mesophase content and do not possess high quality. Furthermore, multiple experiments have revealed that the mesophase pitch products prepared from carbon material raw materials in the various embodiments of the present invention have a stable mesophase content, thus exhibiting high performance stability.

[0194] In summary, the carbon material raw materials prepared in the various embodiments of the present invention have high yields, high contents of tricyclic and tetracyclic aromatic hydrocarbons, and low impurity contents. They can be used to prepare high-quality carbon materials, especially for the co-production of high-quality needle coke and mesophase pitch. The needle coke and mesophase pitch prepared using the carbon material raw materials of the present invention both exhibit high quality and high performance stability.

[0195] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing carbon material raw materials by staged hydrogenation, comprising the following steps: (1) Solvent deasphalting of heavy oil to obtain asphalt and deasphalted oil; (2) Vacuum distillation of the deasphalted oil obtained in step (1) to obtain light distillate, middle distillate and heavy distillate; (3) Selective hydrogenation of the middle distillate obtained in step (2) to obtain the product after selective hydrogenation. (4) The heavy distillate oil obtained in step (2) is subjected to hydrogenation ring-opening treatment to obtain the product after hydrogenation ring-opening treatment; (5) The product after selective hydrogenation treatment obtained in step (3) and the product after hydrogenation ring-opening treatment obtained in step (4) are separated by gas and liquid, and the liquid phase obtained is the carbon material raw material.

2. The method for preparing carbon material raw materials by staged hydrogenation according to claim 1, wherein, In step (1), based on the total mass of the heavy oil as 100%, the heavy oil has a sulfur content of 0.5-5.0%, an asphaltene content of 1-20%, and an effective aromatic hydrocarbon content of 15-40%; and the heavy oil has a nitrogen content of 1000-10000 μg / g and an ash content of 800-7000 ppm.

3. The method for preparing carbon material raw materials by staged hydrogenation according to claim 1, wherein, In step (1), the solvent deasphalting is carried out using an extraction tower. The conditions for solvent deasphalting include: extraction pressure of 1-8 MPa, extraction temperature of 50-300℃, solvent used including alkanes, and the mass ratio of solvent to heavy oil of (0.5-5):

1.

4. The method for preparing carbon material raw materials by staged hydrogenation according to claim 3, wherein, In step (1), based on the total mass of the deasphalted oil as 100%, the sulfur content of the deasphalted oil is 0.6-4.5%, the asphaltene content is 0.1-3.0%, and the effective aromatic hydrocarbon content is 25-45%; and the nitrogen content of the deasphalted oil is 800-6000 μg / g, and the ash content is below 100 ppm.

5. The method for preparing carbon material raw materials by staged hydrogenation according to claim 1, wherein, In step (2), the 10% distillation point temperature of the light distillate oil is 160-260℃, and the 90% distillation point is 300-400℃; the 10% distillation point of the middle distillate oil is 310-390℃, and the 90% distillation point is 400-550℃; the 10% distillation point of the heavy distillate oil is 460-560℃.

6. The method for preparing carbon material raw materials by staged hydrogenation according to claim 5, wherein, In step (2), the 10% distillation point temperature of the light distillate oil is 180-240℃, and the 90% distillation point is 320-360℃; the 10% distillation point of the middle distillate oil is 310-370℃, and the 90% distillation point is 460-500℃; the 10% distillation point of the heavy distillate oil is 470-500℃.

7. The method for preparing carbon material raw materials by staged hydrogenation according to claim 1, wherein, In step (3), the conditions for the selective hydrogenation treatment include: a hydrogen partial pressure of 1.0-20.0 MPa, a temperature of 280-500 °C, and a volume hourly space velocity of 0.5-2.0 h⁻¹. -1 The hydrogen-to-oil ratio is 200-1000.

8. The method for preparing carbon material raw materials by staged hydrogenation according to claim 7, wherein, In step (3), the conditions for the selective hydrogenation treatment include: a hydrogen partial pressure of 2.0-8.0 MPa, a temperature of 300-450 °C, and a volume hourly space velocity of 0.6-1.2 h⁻¹. -1 The hydrogen-to-oil ratio is 300-800.

9. The method for preparing carbon material raw materials by staged hydrogenation according to claim 1, wherein, In step (4), the conditions for the hydrogenation ring-opening treatment include: a hydrogen partial pressure of 5.0-35.0 MPa, a temperature of 300-500 °C, and a volume hourly space velocity of 0.1-1.0 h⁻¹. -1 The hydrogen-to-oil ratio is 200-1500.

10. The method for preparing carbon material raw materials by staged hydrogenation according to claim 9, wherein, In step (4), the conditions for the hydrogenation ring-opening treatment include: a hydrogen partial pressure of 8.0-20.0 MPa, a temperature of 350-450 °C, and a volume hourly space velocity of 0.2-0.8 h⁻¹. -1 The hydrogen-to-oil ratio is 400-1000.

11. The method for preparing carbon material raw materials by staged hydrogenation according to claim 1, wherein, In step (5), based on the total mass of the carbon material raw material as 100%, the effective aromatic hydrocarbon content of the carbon material raw material is 30-55%, the sulfur content is 0.10-0.50%, and the nitrogen content of the carbon material raw material is 200-2000 μg / g.

12. A system for staged hydrogenation to prepare carbon material raw materials, wherein, The system is used to implement the method for preparing carbon material raw materials by staged hydrogenation according to any one of claims 1-11. The system includes: a solvent deasphalting device, a vacuum distillation device, a selective hydrogenation reactor, a hydrogenation ring-opening reactor, and a gas-liquid separation device; wherein, the deasphalted oil outlet of the solvent deasphalting device is connected to the vacuum distillation device, the vacuum distillation device is provided with a light distillate oil outlet, a middle distillate oil outlet, and a heavy distillate oil outlet, the middle distillate oil outlet is connected to the selective hydrogenation reactor, the heavy distillate oil outlet is connected to the hydrogenation ring-opening reactor, and the selective hydrogenation reactor and the hydrogenation ring-opening reactor are connected to the gas-liquid separation device.

13. The system for staged hydrogenation preparation of carbon material raw materials according to claim 12, wherein, The solvent deasphalting device includes an extraction tower.

14. The system for staged hydrogenation preparation of carbon material raw materials according to claim 12, wherein, The vacuum distillation apparatus includes one or both of a stripping tower and a fractionation tower.

15. The system for staged hydrogenation preparation of carbon material raw materials according to claim 12, wherein, The selective hydrogenation reactor and the hydrogenation ring-opening reactor each include one or more of the following: a fixed-bed reactor, a suspended-bed reactor, a fluidized-bed reactor, and a moving-bed reactor.

Images