Method for producing carbon material
阅读说明：本技术 一种生产炭材料的方法 (Method for producing carbon material ) 是由 初人庆 郭丹 方向晨 乔凯 于 2019-05-05 设计创作，主要内容包括：本发明公开一种生产炭材料的方法,所述方法内容如下：原料油与一定比例减压渣油混合后经减压蒸馏装置分离出轻馏分油、中间馏分油及塔底尾油,塔底尾油出装置,所述减压中间馏分油进入加氢处理装置,加氢处理后获得的液相产物经过分馏装置至少分离出加氢轻馏分油和加氢重馏分油,加氢重馏分油与所述减压蒸馏轻馏分油混合后作为形成中间相物料由加热炉a加热后进入焦炭塔,焦炭塔生成的焦化气经焦化分馏塔后获得焦化蜡油,焦化蜡油与所述加氢轻馏分油混合作为拉焦物料由加热炉b加热后进入焦炭塔,焦炭塔依次完成形成中间相阶段和拉焦阶段后获得针状焦。所述方法能够连续生产性能稳定的高品质高端炭材料。(The invention discloses a method for producing a carbon material, which comprises the following steps: raw oil and a certain proportion of vacuum residue oil are mixed and then separated into light distillate oil, middle distillate oil and tower bottom tail oil by a vacuum distillation device, the tower bottom tail oil is discharged from the device, the vacuum middle distillate oil enters a hydrotreating device, a liquid phase product obtained after hydrotreating at least separates hydrogenated light distillate oil and hydrogenated heavy distillate oil by a fractionating device, the hydrogenated heavy distillate oil and the vacuum distillation light distillate oil are mixed to form an intermediate phase material, the intermediate phase material is heated by a heating furnace a and then enters a coke tower, coking gas generated by the coke tower passes through a coking fractionating tower to obtain coking wax oil, the coking wax oil and the hydrogenated light distillate oil are mixed to form a coking material, the coking material is heated by a heating furnace b and then enters the coke tower, and the coke tower sequentially completes the formation of an intermediate phase stage and a coke drawing stage to obtain needle. The method can continuously produce high-quality high-end carbon materials with stable performance.)
1. A method of producing a carbon material, characterized by: the method comprises the following steps: raw oil and a certain proportion of vacuum residue oil are mixed and then separated into light distillate oil, middle distillate oil and tower bottom tail oil by a vacuum distillation device, the tower bottom tail oil is discharged from the device, the vacuum middle distillate oil enters a hydrotreating device, a liquid phase product obtained after hydrotreating at least separates hydrogenated light distillate oil and hydrogenated heavy distillate oil by a fractionating device, the hydrogenated heavy distillate oil and the vacuum distillation light distillate oil are mixed to form an intermediate phase material, the intermediate phase material is heated by a heating furnace a and then enters a coke tower, coking gas generated by the coke tower passes through a coking fractionating tower to obtain coking wax oil, the coking wax oil and the hydrogenated light distillate oil are mixed to form a coking material, the coking material is heated by a heating furnace b and then enters the coke tower, and the coke tower sequentially completes the formation of an intermediate phase stage and a coke drawing stage to obtain needle.
2. The method of claim 1, wherein: the 10 percent distillation point temperature of the vacuum residue is 490-580 ℃, preferably 520-550 ℃.
3. The method of claim 1, wherein: the mass ratio of the raw oil to the vacuum residue is 1:0.2-2.0, preferably 0.5-1.0.
4. The method of claim 1, wherein: the temperature of 10 percent of the distillation point of the light distillate oil of the reduced pressure distillation device is 200-250 ℃, the temperature of 90 percent of the distillation point is 300-400 ℃, the temperature of 10 percent of the distillation point of the reduced pressure middle distillate oil is 310-410 ℃, the temperature of 90 percent of the distillation point is 450-510 ℃, and the temperature of 10 percent of the distillation point of the reduced pressure heavy distillate oil is 460-520 ℃.
5. The method of claim 1, wherein: the 10 percent of distillation point temperature of the hydrogenated light distillate oil is 200-300 ℃, and the 90 percent of distillation point temperature is 330-400 ℃.
6. The method of claim 1, wherein: and (2) mixing hydrogenated heavy distillate oil and the reduced pressure distillation light distillate oil to form a mesophase material, heating the mesophase material by a heating furnace a, and then feeding the mesophase material into a coke tower, wherein the mass ratio of the hydrogenated heavy distillate oil to the reduced pressure light distillate oil is 1: 0.2-1.5.
7. The method of claim 1, wherein: the coke towers are one or more, preferably 3, and any coke is connected with the heating furnace a and the heating furnace b.
8. The method of claim 7, wherein: the total time of the mesophase forming process and the coke drawing process of any coke tower is 16-72 h; the time for the formation of the mesophase is 30-70% of the total time.
9. The method of claim 1, wherein: the outlet temperature of the heating furnace a is controlled by variable temperature, the variable temperature range is 400-480 ℃, the optimal temperature range is 420-480 ℃, and the variable temperature rate is 5-50 ℃/h.
10. The method of claim 1, wherein: the outlet temperature of the heating furnace b is controlled at constant temperature, and the constant temperature range is 490-550 ℃; or the temperature change control is adopted, the temperature change range is 460-550 ℃, and the temperature change speed is 10-100 ℃/h.
11. The method of claim 1, wherein: and (3) mixing the coking wax oil with the hydrogenated light distillate oil to serve as a coke-drawing material, heating the coke-drawing material by a heating furnace b, and then feeding the heated coke-drawing material into a coke tower, wherein the mass ratio of the coking wax oil to the hydrogenated light distillate oil is 1: 0.1-0.8.
Technical Field
The invention relates to a method for producing carbon materials, in particular to a method for producing high-end needle coke.
Background
The needle coke is mainly used for producing high-power and ultrahigh-power graphite electrodes. With the development of the steel era, the yield of scrap steel is gradually increased, the development of electric furnace steel is promoted, the consumption of graphite electrodes, particularly high-power and ultrahigh-power electrodes, is inevitably increased, and the demand of needle coke is continuously increased.
CN201110449286.8 discloses a method for producing homogeneous petroleum needle coke, which comprises the steps of heating raw materials for producing needle coke to a relatively low temperature of 400-480 ℃ by a heating furnace, and then feeding the raw materials into a coking tower, wherein the coking raw materials form mobile mesophase liquid crystal; after the low-temperature fresh raw material feeding stage is finished, gradually raising the outlet temperature of the heating furnace, and simultaneously changing the feeding of the coking heating furnace into fresh raw materials and heavy distillate oil from a fractionating tower; and when the material in the coking tower reaches the temperature of curing and coking, changing the feeding of the coking heating furnace into the coking middle distillate oil generated in the reaction process, and simultaneously increasing the feeding temperature of the coking heating furnace to ensure that the temperature in the coking tower reaches 460-510 ℃, and completing high-temperature curing of the petroleum coke to obtain the needle coke product.
US4235703 discloses a method for producing high-quality coke from residual oil, which comprises the steps of carrying out hydrodesulfurization and demetalization on raw materials, and then carrying out delayed coking to produce high-power electrode petroleum coke.
US4894144 discloses a process for simultaneously preparing needle coke and high-sulfur petroleum coke by pretreating straight-run heavy oil by hydrotreating process, and separating the hydrogenated residual oil into two parts, respectively coking and firing to obtain needle coke and high-sulfur petroleum coke.
CN108587661A discloses a device and a method for preparing needle coke based on a delayed coking process, belonging to the technical field of needle coke. The device comprises a coking mixed oil system, a temperature raising and curing system, a No. 1 coke tower, a No. 2 coke tower and a No. 3 coke tower; the coking mixed oil system is respectively connected with the 1# coke tower, the 2# coke tower and the 3# coke tower, and the temperature raising and solidifying system is respectively connected with the 1# coke tower, the 2# coke tower and the 3# coke tower. According to the device and the method, in the process of preparing the needle coke by the delayed coking process, the process of generating the intermediate phase of the coking mixed oil in the coke tower and the coking process are respectively controlled, so that two-step coking is realized.
The needle coke prepared by the method has the defects of unstable streamline texture, high thermal expansion system and the like, and the comprehensive performance of the needle coke needs to be further improved.
Disclosure of Invention
Aiming at the defects of the prior art, the invention discloses a method for producing a carbon material. The method can continuously produce the needle coke which is a high-quality high-end carbon material with stable performance, has the characteristics of stable streamline texture structure, low thermal expansion coefficient and the like, and meets the use standard of the UHP graphite electrode.
A method for producing a carbon material, the method comprising: raw oil and a certain proportion of vacuum residue oil are mixed and then separated into light distillate oil, middle distillate oil and tower bottom tail oil by a vacuum distillation device, the tower bottom tail oil is discharged from the device, the vacuum middle distillate oil enters a hydrotreating device, a liquid phase product obtained after hydrotreating at least separates hydrogenated light distillate oil and hydrogenated heavy distillate oil by a fractionating device, the hydrogenated heavy distillate oil and the vacuum distillation light distillate oil are mixed to form an intermediate phase material, the intermediate phase material is heated by a heating furnace a and then enters a coke tower, coking gas generated by the coke tower passes through a coking fractionating tower to obtain coking wax oil, the coking wax oil and the hydrogenated light distillate oil are mixed to form a coking material, the coking material is heated by a heating furnace b and then enters the coke tower, and the coke tower sequentially completes the formation of an intermediate phase stage and a coke drawing stage to obtain needle.
In the method of the present invention, the raw material may be a petroleum-based raw material, such as ethylene tar, thermal cracking residual oil, petroleum heavy oil, or catalytic cracking slurry oil, or a mixture of two or more of the above raw materials, or a coal-based raw material, such as coal tar pitch.
In the method, the 10 percent distillation point temperature of the vacuum residue is 490-580 ℃, and preferably 520-550 ℃.
In the method, the mass ratio of the raw material to the vacuum residue is 1:0.2-2.0, preferably 0.5-1.0.
In the method, the temperature of 10 percent of the distillation point of the light distillate oil of the reduced pressure distillation device is 200-250 ℃, the temperature of 90 percent of the distillation point is 300-400 ℃, the temperature of 10 percent of the distillation point of the reduced pressure middle distillate oil is 310-410 ℃, the temperature of 90 percent of the distillation point is 450-510 ℃, and the temperature of 10 percent of the distillation point of the reduced pressure heavy distillate oil is 460-520 ℃.
In the method, the 10 percent distillation point temperature of the hydrogenated light distillate oil is 200-300 ℃, and the 90 percent distillation point temperature is 330-400 ℃.
In the method, hydrogenated heavy distillate oil and the reduced pressure distillation light distillate oil are mixed to form a mesophase material, the mesophase material is heated by a heating furnace a and then enters a coke tower, and the mass ratio of the hydrogenated heavy distillate oil to the reduced pressure light distillate oil is 1: 0.2-1.5.
In the method of the present invention, the hydrotreating can be any hydrotreating technique suitable for the present invention, such as fixed bed residue hydrotreating technique, suspended bed residue hydrotreating technique, boiling bed residue hydrotreating technique, moving bed residue hydrotreating technique, and the like. Taking the industrially well-established fixed bed hydrotreating technique as an example, the adopted hydrotreating catalyst refers to a single catalyst or a combined catalyst having the functions of hydrodemetallization, hydrodesulfurization, hydrodenitrogenation, hydrocracking and the like. These catalysts are generally prepared by using a porous refractory inorganic oxide such as alumina as a carrier, using oxides of metals of group VIB and/or group VIII such as W, Mo, Co, Ni and the like as active components, and selectively adding other various additives such as P, Si, F, B and the like, such as CEN, FZC, ZTN and ZTS series residual oil hydrogenation catalysts produced by catalyst division of the Chinese petrochemical company Limited, and ZTN and ZTS series catalysts produced by the first chemical fertilizer plant of the Qilu petrochemical company. At present, in the fixed bed hydrogenation technology, a plurality of catalysts are often used in combination, wherein a protective agent, a hydrodemetallization catalyst, a hydrodesulfurization catalyst and a hydrodenitrogenation catalyst are used, and the filling sequence is that raw oil is sequentially contacted with the protective agent, the hydrodemetallization, the hydrodesulfurization and the hydrodenitrogenation catalyst. Of course, there is a technique of mixing and packing these catalysts. Hydroprocessing typically places multiple reactors to increase throughput. It is generally carried out at an absolute pressure of from 1MPa to 35MPa, preferably from 2MPa to 6MPa, and at a reaction temperature of from 300 ℃ to 500 ℃ and preferably from 350 ℃ to 450 ℃. The liquid hourly volume space velocity and the hydrogen partial pressure are determined according to the characteristics of the material to be treated and the required conversion rate and the precisionThe depth is selected, and the liquid hourly volume space velocity is generally 0.1h-1-5.0h-1Preferably 0.15h-1-2.0h-1In the range of (1), the total hydrogen-oil volume ratio is 100-.
In the above method, the coke drum may be provided as one or more, preferably 3 coke drums, and any one of the cokes is connected to the heating furnace a and the heating furnace b. The total time of the intermediate phase forming process and the coke drawing process (one-time operation process) of any coke tower is 16-72h, specifically 30h, 40h, 50h and 60 h; the time for forming the intermediate phase is 30-70% of the total time, specifically 40%, 50%, 60% of the total time.
In the method, the outlet temperature of the heating furnace a is controlled by variable temperature, the variable temperature range is 400-480 ℃, the optimal variable temperature range is 420-480 ℃, and the variable temperature rate is 5-50 ℃/h.
In the method, the outlet temperature of the heating furnace b can be controlled at a constant temperature, and the constant temperature range is 490-550 ℃; and the temperature change can also be controlled, wherein the temperature change range is 460-550 ℃, and the temperature change rate is 10-100 ℃/h.
In the method, the top pressure of the coke tower is 0.2-1.5 MPa.
In the method, the 10 percent of distillation point temperature of the coking wax oil obtained by the coking fractionating tower is 250-400 ℃.
In the method, the coking wax oil and the hydrogenated light distillate oil are mixed to be used as a coke pulling material, the coke pulling material is heated by a heating furnace b and then enters a coke tower, and the mass ratio of the coking wax oil to the hydrogenated light distillate oil is 1: 0.1-0.8.
Compared with the prior art, the method for producing the carbon material provided by the invention has the following beneficial effects:
1) according to the method, the reduced pressure middle distillate oil is used as the feeding material of the hydrogenation device, and the hydrogenated heavy distillate oil and the reduced pressure light distillate oil are mixed to produce the needle coke, so that the yield of the needle coke product can be improved, and the application performance of the needle coke is further improved compared with the method for producing the needle coke by only adopting the hydrogenation material;
2) according to the invention, the hydrogenated light fraction and the coking wax oil are mixed to serve as the coke-drawing raw material, so that the sulfur content of the needle coke is further reduced, meanwhile, the production of isotropic coke can be further reduced, the micro-fiber structure of the needle coke is improved, the quality of the needle coke product is improved, and the thermal expansion coefficient of the needle coke is reduced;
3) in the intermediate phase production stage and the coke drawing stage of the coke tower, a set of heating furnace is respectively and independently arranged, for each set of heating furnace, the feeding quantity and the feeding property are stable, the temperature change range is narrowed, the operation fluctuation is small, especially, the heating furnace b can realize constant temperature operation, and the stable production of high-quality needle coke products is ensured;
4) the invention adopts the vacuum residue oil and the raw material to be mixed and enter the vacuum distillation device, which is beneficial to further reducing the ash content in the raw material, thereby reducing the ash content in the needle coke product and improving the application performance of the needle coke product.
Drawings
FIG. 1 is an optimized flow chart of a method for producing needle coke by a combined process.
Detailed Description
The following detailed description of the embodiments of the present invention is provided, but it should be noted that the scope of the present invention is not limited by the embodiments.
The raw material 1 and vacuum residue oil are mixed and then enter a
In the context of the present invention, including in the examples and comparative examples, the coefficient of thermal expansion is determined according to international standard GB/T3074.4 "determination of Coefficient of Thermal Expansion (CTE) of graphite electrodes", the volatiles are determined according to petrochemical standard SH/T0313 "petroleum coke test method", the true density is determined according to international standard GB/T6155 "determination of true density of carbon material", the resistivity is determined according to GB 242530-2009 "determination of resistivity of carbon material", the process of needle coke micro-compositional analysis is as follows: the raw coke for preparing the needle coke is calcined in a 900 ℃ tube furnace, sampled and ground to obtain a coke particle sample of 0.2-0.8mm, and then the sample is made into a polished section, and the microstructure of the needle coke is observed under an oil lens with a light source of orthogonal polarization and an eyepiece of 10 times and an objective of 50 times.