A method for producing high-particle-strength needle coke

Abstract

This invention discloses a method for producing high-particle-strength needle coke. The method includes the following steps: After heating, feedstock oil is introduced into a coking tower for coking. After coking, a coking feedstock is switched for coking processing. The coking feedstock is at least two types, denoted as feedstock A and feedstock B. Feedstock A has a 5% distillation point temperature of 300℃-380℃, preferably 340℃-360℃, and a 95% distillation point temperature of 400℃-520℃, preferably 410℃-460℃. Feedstock B has a 5% distillation point temperature of 250℃-350℃, preferably 250℃-300℃, and a 95% distillation point temperature of 350℃-450℃, preferably 350℃-400℃. Feedstock A and feedstock B are coked in a sequential manner. This method can produce high-particle-strength needle coke.

Description

Technical Field

[0001] This invention relates to a method for producing high-particle-strength needle coke, and more specifically to a method for producing high-particle-strength needle coke using petroleum-based or coal-based raw materials. Background Technology

[0002] Needle coke is an excellent carbon product, exhibiting a distinct streamlined texture. Due to its good electrical conductivity, orientation, and thermal conductivity, it has become a primary raw material for manufacturing ultra-high power graphite electrodes for steelmaking. Using ultra-high power electrodes in steelmaking can shorten smelting time by about two-thirds and reduce power consumption by about 50%, resulting in significant economic benefits.

[0003] CN202011305509.9 discloses a method and process system for producing needle coke from heavy oil, comprising: a fractional cutting process, using heavy oil as raw material to cut it into light distillate oil, heavy distillate oil and tailings; a hydrogenation process, wherein the heavy distillate oil is hydrogenated to obtain hydrogenated heavy distillate; a mixing process, wherein the hydrogenated heavy distillate is mixed with the light distillate oil to obtain a mixed oil; and a delayed coking process, wherein the mixed oil is subjected to delayed coking to obtain needle coke.

[0004] US4894144 discloses a method for simultaneously preparing needle coke and high-sulfur petroleum coke. It employs a hydrotreating process to pretreat straight-run heavy oil, and the hydrotreated residue is divided into two parts, which are then coked separately and subsequently calcined to obtain needle coke and high-sulfur petroleum coke.

[0005] US5286371 also discloses a hydrotreating process for straight-run residue, with a hydrotreating reaction temperature of 379-480℃ and a reaction pressure of 6.8MPa-34.4MPa. The treated heavy residue is mixed with catalytic cracking clarified oil and fed into a solvent deasphalting unit. The stream after deasphalting is used as feedstock for needle coke.

[0006] US4178229 discloses a method for producing high-quality petroleum coke from straight-run vacuum residue, which first converts vacuum residue into distillate oil and bitumen, and then further cracks the bitumen and hydrogen donor to produce feedstock for high-quality coke.

[0007] CN202010439340.X discloses a method for preparing needle coke for ultra-high power electrodes from heavy oil. The method uses heavy oil as raw material and employs a size exclusion separation method with polystyrene as the separation column packing to separate components with a relative molecular mass distribution of 400-1000. Acidic and basic components are removed by ion exchange chromatography to obtain a neutral raw material. The treated raw material undergoes a two-stage continuous carbonization process to prepare needle coke.

[0008] Needle coke is used as aggregate in the production of HP and UHP graphite electrodes. The main goal is to achieve a low coefficient of thermal expansion (CTE). To obtain needle coke products with a low CTE value, the coking process must follow the liquid phase carbonization theory. That is, the raw material coking process must be carried out slowly from low temperature to high temperature to form a fully developed mesophase structure before solidification into coke. However, in actual production, although a low coefficient of thermal expansion is obtained, its particle strength is generally low. Summary of the Invention

[0009] Through in-depth research, the inventors discovered that the thermal reaction time and temperature of raw materials entering the coke tower at different stages of the coking process vary. This causes some raw materials to fail to undergo liquid-phase carbonization before high-temperature coking, resulting in low strength needle coke particles and affecting the application performance of the needle coke. To address the shortcomings of existing technologies, this invention provides a method for producing high-strength needle coke.

[0010] A method for producing high-particle-strength needle coke, the method comprising the following steps: After heating, feedstock oil is introduced into a coking tower for coking; after coking, a coking feedstock is switched for coking treatment. The coking feedstock is at least two types, denoted as feedstock A and feedstock B. Feedstock A has a 5% distillation point temperature of 300℃-380℃, preferably 340℃-360℃, and a 95% distillation point temperature of 400℃-520℃, preferably 410℃-460℃; feedstock B has a 5% distillation point temperature of 250℃-350℃, preferably 250℃-300℃, and a 95% distillation point temperature of 350℃-450℃, preferably 350℃-400℃. Feedstock A and feedstock B are coked in a sequential order.

[0011] In the method of the present invention, the conditions for coking raw material A are as follows: the outlet temperature of the heating furnace is 450℃-550℃, preferably 480℃-530℃; the coking time is 10-24h, preferably 12-18h; and the coke tower pressure is 0.1-1.0MPa, preferably 0.2-0.8MPa, more preferably 0.3-0.6MPa.

[0012] In the method of the present invention, the conditions for coking of raw material B are as follows: the outlet temperature of the heating furnace is 450℃-550℃, preferably 480℃-530℃; the charging time is 1-15h, preferably 2-10h; and the coke tower pressure is 0.1-1.0MPa, preferably 0.1-0.3MPa.

[0013] In the method of the present invention, the solid content of the feed oil is 0-500 μg / g, preferably 0-200 μg / g, more preferably 0-100 μg / g; the 5% distillation point temperature is 350℃-450℃, preferably 370℃-410℃, and the 95% distillation temperature is 450℃-550℃, preferably 480℃-500℃; the sulfur content is 0-1.0%, preferably 0-0.5%, more preferably 0-0.4%.

[0014] In the method of the present invention, the conditions for coking the raw material oil are as follows: the furnace outlet temperature of the heating furnace is 400℃-580℃, preferably 450℃-550℃, more preferably 480℃-520℃; the charging time is 4-30h, preferably 15-25h; and the coke tower pressure is 0.1-1.5MPa, preferably 0.3-1.0MPa, more preferably 0.4-0.8MPa.

[0015] In the method of the present invention, the mass ratio of the feedstock oil, coking feedstock A, and coking feedstock B to the single coke tower is 1:0.2-2.0:0.1-2.0.

[0016] A method for producing high-particle-strength needle coke specifically includes the following:

[0017] (6) Fresh feedstock enters the hydrotreating tower after passing through the hydrotreating unit, at least separating out the hydrotreated distillate oil;

[0018] (7) The hydrogenated distillate oil is heated in a heating furnace and then fed into the coking tower. The oil and gas generated by the reaction are discharged from the top of the coking tower and enter the coking fractionation tower to separate at least the heavy coking wax oil fraction and the light coking wax oil fraction.

[0019] (8) The hydrotreated distillate in step (2) is switched to the coking heavy distillate in step (2) to continue feeding the coke tower;

[0020] (9) The coking heavy wax oil fraction in step (3) is switched to the coking light wax oil fraction in step (2) to continue feeding the coke tower;

[0021] (10) In step (4), after the coking light wax oil finishes charging the coke tower, the coke tower is subjected to small blowing, large blowing, and coke removal operations, and the needle coke product exits the device from the bottom of the tower.

[0022] In the above method, the fresh raw material in step (1) is selected from at least one of coal-based raw materials and petroleum-based raw materials, preferably selected from at least one of coal tar, coal tar pitch, heavy petroleum oil, ethylene tar, catalytic cracking slurry oil or thermal cracking residue oil.

[0023] In the above method, the solid content of the fresh raw material in step (1) is 0-500 μg / g, preferably 0-200 μg / g, and more preferably 0-100 μg / g;

[0024] In the above method, the hydrotreating device in step (1) can be any hydrotreating technology suitable for this invention, such as fixed-bed residue hydrotreating technology, suspended-bed residue hydrotreating technology, fluidized-bed residue hydrotreating technology, moving-bed residue hydrotreating technology, etc. Taking the currently mature fixed-bed hydrotreating technology as an example, the hydrotreating catalyst used refers to a single catalyst or a combination catalyst with functions such as hydrodemetallization, hydrodesulfurization, hydrodenitrogenation, and hydrocracking. These catalysts generally use porous refractory inorganic oxides such as alumina as a support, oxides of Group VIB and / or Group VIII metals such as W, Mo, Co, Ni, etc. as active components, and selectively add other various additives such as P, Si, F, B, etc. For example, the CEN, FZC, ZTN, and ZTS series residue hydrotreating catalysts produced by the Catalyst Branch of China Petroleum & Chemical Corporation, and the ZTN and ZTS series catalysts produced by the First Fertilizer Plant of Qilu Petrochemical Company belong to this type of catalyst. Currently, in fixed-bed hydrotreating technology, multiple catalysts are often used in combination, including a protective agent, a hydrodemetallization catalyst, a hydrodesulfurization catalyst, and a hydrodenitrogenation catalyst. The loading sequence is generally such that the feedstock oil comes into contact with the protective agent, hydrodemetallization catalyst, hydrodesulfurization catalyst, and hydrodenitrogenation catalyst in sequence. Of course, there are also techniques that mix and load these catalysts. Hydrotreating typically involves multiple reactors to increase processing capacity. Operation is usually carried out at an absolute pressure of 1 MPa-35 MPa, preferably 2 MPa-6 MPa, and a reaction temperature of 250℃-500℃, preferably 250℃-350℃. The liquid hourly space velocity (LHSV) and hydrogen partial pressure (HBP) are selected based on the characteristics of the feedstock, the required conversion rate, and the degree of refining. The LHSV is typically around 0.1 h⁻¹. -1 -5.0h -1 Ideally, it should be 0.15h. -1 -2.0h -1 Within the range, the total hydrogen-to-oil volume ratio is 100-5000, preferably 300-3000.

[0025] In the above method, the 5% distillation point temperature of the hydrogenated distillate oil in step (1) is 350℃-450℃, preferably 370℃-410℃, and the 95% distillation point temperature is 450℃-550℃, preferably 480℃-500℃.

[0026] In the above method, the sulfur content of the hydrogenated distillate oil in step (1) is 0-1.0%, preferably 0-0.5%, and more preferably 0-0.4%.

[0027] In the above method, the hydrogenated distillate oil in step (2) is passed through a heating furnace with an outlet temperature of 400℃-580℃, preferably 450℃-550℃, and more preferably 480℃-520℃.

[0028] In the above method, the charging time of the hydrotreated distillate oil to the coke tower in step (2) is 4-30h, preferably 15-25h, and the coke tower pressure is 0.1-1.5MPa, preferably 0.3-1.0MPa, and more preferably 0.4-0.8MPa;

[0029] In the above method, the 5% distillation point temperature of the coking heavy wax oil fraction in step (3) is 300℃-380℃, preferably 340℃-360℃, and the 95% distillation point temperature is 400℃-520℃, preferably 410℃-460℃.

[0030] In the above method, the charging process of coking heavy wax oil fraction in step (3) has a furnace outlet temperature of 450℃-550℃, preferably 480℃-530℃; a charging time of 10-24h, preferably 12-18h; and a coke tower pressure of 0.1-1.0MPa, preferably 0.2-0.8MPa, more preferably 0.3-0.6MPa.

[0031] In the above method, the 5% distillation point temperature of the coking light wax oil fraction in step (4) is 250℃-350℃, preferably 250℃-300℃, and the 95% distillation point temperature is 350℃-450℃, preferably 350℃-400℃.

[0032] In the above method, the charging process of coking light wax oil fraction in step (4) has a furnace outlet temperature of 450℃-550℃, preferably 480℃-530℃; a charging time of 1-15h, preferably 2-10h; and a coke tower pressure of 0.1-1.0MPa, preferably 0.1-0.3MPa.

[0033] In the above method, the mass ratio of hydrogenated distillate oil, coking heavy wax oil fraction, and coking light wax oil to the charge of a single coke tower is 1:0.2-2.0:0.1-2.0.

[0034] Through experiments, the inventors discovered that the strength of needle coke is closely related to the medium and operating conditions during the coking process. Especially in the later stages of coking, when the main product of needle coke has solidified, the coking medium continues to react and form coke, resulting in very low-strength petroleum coke. This invention uses coking light wax oil and heavy wax oil to carry out the coking process of needle coke. The main function of heavy wax oil coking is to raise the temperature and solidify the system, while the main function of light wax oil coking is to further provide heat to the solidified needle coke product to increase its strength, while significantly reducing the generation of low-strength needle coke by the coking medium. Attached Figure Description

[0035] Figure 1This is a flowchart of a combined process for preparing needle coke according to the present invention, wherein 1 is fresh raw material, 2 is hydrotreating unit, 3 is hydrotreating product pipeline, 4 is fractionation tower, 5 is hydrotreating gas product pipeline, 6 is light diesel oil and below fraction pipeline, 7 is hydrotreating distillate oil, 8 is coking furnace, 9 is coke tower, 10 is coking product pipeline, 11 is coking fractionation tower, 12 is coking gas, 13 is coking gasoline, 14 is coking diesel, 15 is coking heavy wax oil fraction, and 16 is coking light wax oil fraction. Detailed Implementation

[0036] The specific embodiments of the present invention will be described in detail below. However, it should be noted that the scope of protection of the present invention is not limited to these specific embodiments, but is determined by the claims in the appendix.

[0037] All publications, patent applications, patents, and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings commonly understood by those skilled in the art. In case of conflict, the definitions in this specification shall prevail.

[0038] When this specification uses the prefixes “known to those skilled in the art,” “prior art,” or similar terms to derive materials, substances, methods, steps, apparatus, or components, the objects derived from such prefixes cover those commonly used in the art at the time of this application, but also include those that are not currently commonly used but will become generally recognized in the art as suitable for similar purposes.

[0039] Unless otherwise specified, all percentages, parts, ratios, etc. mentioned in this specification are based on weight, unless being based on weight would not be in accordance with the common understanding of those skilled in the art.

[0040] In the context of this specification, any two or more embodiments of the present invention can be arbitrarily combined, and the resulting technical solutions are part of the original disclosure of this specification and also fall within the protection scope of the present invention.

[0041] According to one embodiment of the present invention, there is no particular limitation on the type of separation tower. Any separation device that can separate the material fed to the separation tower into multiple components according to predetermined requirements can be used. Specifically, distillation towers, flash distillation towers, evaporation towers, or fractionation towers can be used, with fractionation towers being preferred.

[0042] In the context of this invention, including in the embodiments and comparative examples, the coefficient of thermal expansion was determined according to the international standard GB / T3074.4 "Determination of Coefficient of Thermal Expansion (CTE) of Graphite Electrodes", the particle strength coefficient was determined according to T / ZGTS002-2019, the volatile matter was determined according to the petrochemical standard SH / T0313 "Test Method for Petroleum Coke", the true density was determined according to the international standard GB / T32158, and the sulfur content was determined according to GB / T24256.

[0043] The present invention will be further described in detail below through embodiments and comparative examples, but the present invention is not limited to the following embodiments.

[0044] like Figure 1 As shown: Fresh feedstock 1 passes through hydrogenation unit 2, and the hydrogenation product enters hydrogenation fractionation tower 4 via pipeline 3, separating gas, light diesel oil and lower fractions, and hydrogenated distillate oil. The gas and light diesel oil and lower fractions exit the unit via pipelines 5 and 6, respectively. The hydrogenated distillate oil enters coke 9 via pipeline 7 through heater 8 and then through a four-way valve. The oil and gas generated by coking enter the coking fractionation tower 11 from the top of the coke tower via pipeline 10, separating coking gas 12, coking gasoline 13, coking diesel 14, coking heavy wax oil fraction 15, and coking light wax oil fraction 16. Among them, coking heavy wax oil fraction 15 and coking light wax oil fraction 16 enter the coke tower for coking and feeding in sequence via heater 8. The produced needle coke product exits the unit from the bottom of the coke tower.

[0045] Example 1

[0046] The properties of the feedstock provided by a refinery are shown in Table 1. The catalyst used in the hydrotreating unit is the CEN, FZC, ZTN, and ZTS series of residue hydrotreating catalysts produced by the Catalyst Division of China Petroleum & Chemical Corporation (Sinopec). Specifically, it includes a protective agent, a demetallization catalyst, a desulfurization catalyst, and a denitrification catalyst. The loading sequence is generally to allow the feedstock to contact the protective agent, hydrodemetallization catalyst, hydrodesulfurization catalyst, and hydronitrification catalyst in sequence. Of course, there are also techniques that mix and load these catalysts. The catalyst loading techniques described above are well-known to those skilled in the art. The hydrotreating process conditions are shown in Table 2.

[0047] Fresh feedstock is processed through a hydrogenation unit to obtain hydrogenated distillate oil. The properties of the hydrogenated distillate oil are as follows: 5% distillation point temperature is 380℃, 95% distillation point temperature is 500℃, and sulfur content is 0.32%. The charging conditions for the coke tower with the hydrogenated distillate oil are as follows: furnace outlet temperature is 480℃, charging time is 15h, and coke tower pressure is 0.7MPa. The preferred 5% distillation point temperature for the coking heavy wax oil fraction is 355℃, and the preferred 95% distillation point temperature is... The charging conditions for the coking tower of the heavy coking wax oil fraction at 455℃ are as follows: furnace outlet temperature 495℃, charging time 12h, and coking tower pressure 0.6MPa. The 5% distillation point temperature and 95% distillation point temperature of the light coking wax oil fraction are 295℃ and 385℃, respectively. The charging conditions for the light coking wax oil fraction of the coking tower are as follows: furnace outlet temperature 480℃, charging time 4h, and coking tower pressure 0.2MPa. The mass ratio of hydrogenated distillate, heavy coking wax oil fraction, and light coking wax oil to a single coking tower is 1:1:0.5. The properties of the obtained needle coke product are shown in Table 3.

[0048] Comparative Example 1

[0049] The process of feeding coke tower with light coking wax oil was cancelled, and heavy coking wax oil was used instead of light coking wax oil to complete the coking stage of light coking wax oil in Example 1. All other conditions were exactly the same as in Example 1. The properties of the needle coke product obtained are shown in Table 3.

[0050] Comparative Example 2

[0051] The process of charging the coke tower with heavy coking wax oil was eliminated, and light coking wax oil was used instead of heavy coking wax oil to complete the coking stage of heavy coking wax oil in Example 1. All other conditions were exactly the same as in Example 1. The properties of the needle coke product obtained are shown in Table 3.

[0052] Table 1 Properties of Raw Materials

[0053] Analysis Project Fresh ingredients <![CDATA[Density g / cm 3 > 1.0325 Ash content % 0.01 C%(w) 90.05 H%(w) 7.86 S%(w) 1.98 N% (w) 0.11 Four components % (w) Saturated portion 18.62 Aromatic components 76.80 gelatinous 4.26 Asphalt 0.32

[0054] Table 2 Hydrogenation Process Conditions

[0055] project Operating conditions raw material Fresh ingredients Hydrogen partial pressure, MPa 5.0 Reaction temperature, °C 310 <![CDATA[Space velocity, h -1 > 1.0 Hydrogen-to-oil ratio 800

[0056] Table 3 Properties of needle coke produced in the examples and comparative examples

[0057]

[0058]

[0059] Example 2

[0060] The properties of the feedstock provided by a refinery are shown in Table 4. The catalyst used in the hydrotreating unit is the CEN, FZC, ZTN, and ZTS series of residue hydrotreating catalysts produced by the Catalyst Division of China Petroleum & Chemical Corporation (Sinopec). Specifically, it includes a protective agent, a demetallization catalyst, a desulfurization catalyst, and a denitrification catalyst. The loading sequence is generally to allow the feedstock to contact the protective agent, hydrodemetallization catalyst, hydrodesulfurization catalyst, and hydronitrification catalyst in sequence. Of course, there are also techniques that mix and load these catalysts. The catalyst loading techniques described above are well-known to those skilled in the art. The hydrotreating process conditions are shown in Table 5.

[0061] Fresh feedstock is processed through a hydrotreating unit to obtain hydrotreated distillate oil. The properties of the hydrotreated distillate oil are as follows: 5% distillation point temperature is 410℃, 95% distillation point temperature is 490℃, and sulfur content is 0.26%. The charging conditions for the coke tower with the hydrotreated distillate oil are as follows: furnace outlet temperature is 495℃, charging time is 24 hours, and coke tower pressure is 0.5 MPa. The 5% distillation point temperature of the coking heavy wax oil fraction is 345℃, and the 95% distillation point temperature is 415℃.

[0062] The charging conditions for the coking tower of heavy coking wax oil fraction are as follows: furnace outlet temperature 510℃, charging time 15h, and coking tower pressure 0.5MPa. The 5% distillation point temperature and 95% distillation point temperature of the light coking wax oil fraction are 260℃ and 385℃, respectively. The charging conditions for the light coking wax oil fraction of the coking tower are as follows: furnace outlet temperature 500℃, charging time 8h, and coking tower pressure 0.3MPa. The mass ratio of hydrotreated distillate, heavy coking wax oil fraction, and light coking wax oil to a single coking tower is 1:0.8:0.6. The properties of the obtained needle coke product are shown in Table 6.

[0063] Table 4 Properties of Raw Materials

[0064]

[0065]

[0066] Table 5 Hydrogenation Process Conditions

[0067] project Operating conditions raw material Fresh ingredients Hydrogen partial pressure, MPa 4.0 Reaction temperature, °C 300 <![CDATA[Space velocity, h -1 > 1.2 Hydrogen-to-oil ratio 1000

[0068] Example 3

[0069] Fresh feedstock is processed through a hydrogenation unit to obtain hydrogenated distillate oil. The properties of the hydrogenated distillate oil are as follows: 5% distillation point temperature is 375℃, 95% distillation point temperature is 495℃, and sulfur content is 0.30%. The charging conditions for the coke tower with the hydrogenated distillate oil are as follows: furnace outlet temperature is 485℃, charging time is 20h, and coke tower pressure is 0.7MPa. The 5% distillation point temperature of the coking heavy wax oil fraction is 350℃, and the 95% distillation point temperature is 495℃. The charging conditions for the coking tower of heavy coking wax oil fraction at 30℃ are as follows: furnace outlet temperature 495℃, charging time 14h, and coking tower pressure 0.7MPa. The 5% distillation point temperature and 95% distillation point temperature of the light coking wax oil fraction are 260℃ and 360℃, respectively. The charging conditions for the light coking wax oil fraction of the coking tower are as follows: furnace outlet temperature 530℃, charging time 4h, and coking tower pressure 0.2MPa. The mass ratio of hydrotreated distillate, heavy coking wax oil fraction, and light coking wax oil to a single coking tower is 1:0.9:0.4. The properties of the obtained needle coke product are shown in Table 6.

[0070] Table 6. Properties of needle coke in the examples

[0071] project Example 2 Example 3 <![CDATA[Coefficient of thermal expansion, 10 -6 / ℃]]> 0.97 0.98 Volatile matter, w% 5.36 5.64 Ash content, w% 0.02 0.01 Moisture content, w% 0.54 0.59 Sulfur content, w% 0.32 0.33 <![CDATA[True density, g / cm 3 > 1.45 1.42 Particle strength coefficient, % 23.58 23.66

Claims

1. A method for producing high-particle-strength needle coke, characterized in that: The method includes the following steps: the feed oil is heated and then introduced into a coking tower for coking; after coking, the feed oil is switched to coking feed for coking treatment. The coking feed is at least two types, denoted as feed A and feed B. The 5% distillation temperature of feed A is 300℃-380℃, and the 95% distillation temperature is 400℃-520℃; the 5% distillation temperature of feed B is 250℃-350℃, and the 95% distillation temperature is 350℃-450℃. Feed A and feed B are coked in sequence. Feed A is a heavy wax oil fraction from coking, and feed B is a light wax oil fraction from coking. The conditions for coking raw material A are as follows: furnace outlet temperature 450℃-550℃; charging time 10-24h; coke tower pressure 0.1-1.0MPa; The conditions for coking raw material B are as follows: furnace outlet temperature is 450℃-550℃; charging time is 1-15h; coke tower pressure is 0.1-1.0MPa.

2. The method according to claim 1, characterized in that: The 5% distillation temperature of raw material A is 340℃-360℃, and the 95% distillation temperature is 410℃-460℃; the 5% distillation temperature of raw material B is 250℃-300℃, and the 95% distillation temperature is 350℃-400℃.

3. The method according to claim 1, characterized in that: The conditions for coking raw material A are as follows: furnace outlet temperature is 480℃-530℃; charging time is 12-18h; coke tower pressure is 0.2-0.8MPa.

4. The method according to claim 3, characterized in that: The conditions for coking raw material A are: coke tower pressure of 0.3-0.6 MPa.

5. The method according to claim 1, characterized in that: The conditions for coking raw material B are as follows: furnace outlet temperature is 480℃-530℃; charging time is 2-10h; coke tower pressure is 0.1-0.3MPa.

6. The method according to claim 1, characterized in that: The feedstock oil has a solid content of 0-500 µg / g; a 5% distillation temperature of 350℃-450℃ and a 95% distillation temperature of 450℃-550℃; and a sulfur content of 0-1.0%.

7. The method according to claim 6, characterized in that: The feedstock oil has a solid content of 0-200 µg / g; a 5% distillation temperature of 370℃-410℃ and a 95% distillation temperature of 480℃-500℃; and a sulfur content of 0-0.5%.

8. The method according to claim 6, characterized in that: The raw material oil has a solid content of 0-100 µg / g and a sulfur content of 0-0.4%.

9. The method according to claim 1, characterized in that: The conditions for coking the feedstock oil are as follows: the furnace outlet temperature is 400℃-580℃; the charging time is 4-30h; and the coke tower pressure is 0.1-1.5MPa.

10. The method according to claim 9, characterized in that: The conditions for coking the feedstock oil are as follows: the furnace outlet temperature is 450℃-550℃; the charging time is 15-25h; and the coke tower pressure is 0.3-1.0MPa.

11. The method according to claim 9, characterized in that: The conditions for coking the feedstock oil are: the furnace outlet temperature of the heating furnace is 480℃-520℃; and the coke tower pressure is 0.4-0.8MPa.

12. The method according to claim 1, characterized in that: The mass ratio of the feedstock oil, coking feedstock A, and coking feedstock B to the single coke tower is 1:0.2-2.0:0.1-2.

0.

13. The method according to claim 1, characterized in that: The specific production methods for high-particle-strength needle coke include the following: (1) Fresh feedstock enters the hydrotreating tower after passing through the hydrotreating unit, at least separating the hydrotreated distillate oil; (2) The hydrogenated distillate is heated in a heating furnace and then fed into the coking tower. The oil and gas generated by the reaction are discharged from the top of the coking tower and enter the coking fractionation tower to separate at least the heavy coking wax oil fraction and the light coking wax oil fraction. (3) The hydrotreated distillate in step (2) is switched to the coking heavy wax oil fraction in step (2) to continue feeding the coke tower; (4) The coking heavy wax oil fraction in step (3) is switched to the coking light wax oil fraction in step (2) to continue feeding the coke tower; (5) After the coking light wax oil fraction in step (4) finishes feeding the coke tower, the coke tower is subjected to small blowing, large blowing and coke removal operations, and the needle coke product exits the device from the bottom of the tower.

14. The method according to claim 13, characterized in that: The fresh raw material mentioned in step (1) is selected from at least one of coal-based raw materials and petroleum-based raw materials.

15. The method according to claim 14, characterized in that: The fresh raw material mentioned in step (1) is selected from at least one of coal tar, coal tar pitch, petroleum heavy oil, ethylene tar, catalytic cracking slurry oil or thermal cracking residue oil.

16. The method according to claim 13, characterized in that: The solid content of the fresh raw materials mentioned in step (1) is 0-500µg / g.

17. The method according to claim 16, characterized in that: The solid content of the fresh raw materials mentioned in step (1) is 0-200µg / g.

18. The method according to claim 16, characterized in that: The solid content of the fresh raw materials mentioned in step (1) is 0-100µg / g.

19. The method according to claim 13, characterized in that: Step (1) The hydrotreating device is one of the following: a fixed bed residue oil hydrotreating device, a suspended bed residue oil hydrotreating device, a fluidized bed residue oil hydrotreating device, or a moving bed residue oil hydrotreating device.

20. The method according to claim 13, characterized in that: The hydrogenated distillate oil described in step (1) has a 5% distillation temperature of 350℃-450℃ and a 95% distillation temperature of 450℃-550℃.

21. The method according to claim 20, characterized in that: The hydrogenated distillate oil described in step (1) has a 5% distillation temperature of 370℃-410℃ and a 95% distillation temperature of 480℃-500℃.

22. The method according to claim 13, characterized in that: The sulfur content of the hydrogenated distillate oil in step (1) is 0-1.0%.

23. The method according to claim 22, characterized in that: The sulfur content of the hydrogenated distillate oil in step (1) is 0-0.5%.

24. The method according to claim 22, characterized in that: The sulfur content of the hydrogenated distillate oil in step (1) is 0-0.4%.

25. The method according to claim 13, characterized in that: The hydrotreated distillate oil described in step (2) is passed through a heating furnace with an outlet temperature of 400℃-580℃.

26. The method according to claim 25, characterized in that: The hydrotreated distillate oil described in step (2) is passed through a heating furnace with an outlet temperature of 450℃-550℃.

27. The method according to claim 25, characterized in that: The hydrogenated distillate oil described in step (2) is passed through a heating furnace with an outlet temperature of 480℃-520℃.

28. The method according to claim 13, characterized in that: The charging time of the hydrotreated distillate oil to the coke tower in step (2) is 4-30 hours, and the pressure of the coke tower is 0.1-1.5 MPa.

29. The method according to claim 28, characterized in that: The charging time of the hydrogenated distillate oil to the coke tower in step (2) is 15-25 hours, and the pressure of the coke tower is 0.3-1.0 MPa.

30. The method according to claim 28, characterized in that: Step (2), the pressure of the coke tower is 0.4-0.8 MPa.

31. The method according to claim 13, characterized in that: The distillation temperature of the 5% coking heavy wax oil fraction in step (3) is 300℃-380℃, and the distillation temperature of the 95% fraction is 400℃-520℃.

32. The method according to claim 31, characterized in that: The distillation temperature of the 5% coking heavy wax oil fraction in step (3) is 340℃-360℃, and the distillation temperature of the 95% fraction is 410℃-460℃.

33. The method according to claim 13, characterized in that: In step (3), the charging process of the coking heavy wax oil fraction is as follows: the outlet temperature of the heating furnace is 450℃-550℃; the charging time is 10-24h; and the coke tower pressure is 0.1-1.0MPa.

34. The method according to claim 33, characterized in that: In step (3), the charging process of the coking heavy wax oil fraction has a furnace outlet temperature of 480℃-530℃, a charging time of 12-18h, and a coke tower pressure of 0.2-0.8MPa.

35. The method according to claim 33, characterized in that: Step (3), the pressure of the coke tower is 0.3-0.6 MPa.

36. The method according to claim 13, characterized in that: The 5% distillation temperature of the coking light wax oil fraction in step (4) is 250℃-350℃, and the 95% distillation temperature is 350℃-450℃.

37. The method according to claim 36, characterized in that: The 5% distillation temperature of the coking light wax oil fraction in step (4) is 250℃-300℃, and the 95% distillation temperature is 350℃-400℃.

38. The method according to claim 13, characterized in that: In step (4), the charging process of coking light wax oil fraction is carried out with the furnace outlet temperature being 450℃-550℃, the charging time being 1-15h, and the coke tower pressure being 0.1-1.0MPa.

39. The method according to claim 38, characterized in that: In step (4), the charging process of coking light wax oil fraction is carried out with a furnace outlet temperature of 480℃-530℃, a charging time of 2-10h, and a coke tower pressure of 0.1-0.3MPa.

40. The method according to claim 13, characterized in that: The mass ratio of the hydrogenated distillate oil, the coking heavy wax oil fraction, and the coking light wax oil fraction to the charge of a single coke tower is 1:0.2-2.0:0.1-2.0.

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