RU-2861455-C1 - METHOD FOR PRODUCING ISOTROPIC COKE

Abstract

FIELD: chemical industry. SUBSTANCE: invention relates to a technology for producing coke raw material for the production of carbon-containing materials, in particular isotropic coke. The method consists in producing isotropic coke by coking the starting raw material in a batch still to obtain coking distillates. The starting raw material, which is petroleum raw material - heavy catalytic cracking gas oil or coal raw material - coal tar pitch with a softening point of up to 60°C, is mixed in a mixing tank with polyacrylonitrile in an amount of 2.5 to 20 mas.%, the resulting mixtures are sent to a batch still. In the still, the mixture of heavy catalytic cracking gas oil with polyacrylonitrile is heated to a temperature of 495-505°C, and the mixture of coal tar pitch with polyacrylonitrile is heated to a temperature of 510-520°C, at a rate of 110 degrees per hour and a pressure of 0.3 to 0.4 MPa, to obtain raw and pitch coke, as well as coking distillates. The raw and pitch coke are unloaded from the batch still and sent to a furnace for calcination in an inert nitrogen atmosphere at a temperature of at least 1300°C for one hour to obtain calcined isotropic structure coke. EFFECT: obtaining coke with increased static strength up to 12.6 MPa. 1 cl, 6 tbl, 13 ex

Inventors

• Gabdulkhakov Renat Railevich
• Govkelevich Kseniia Iurevna
• Rudko Viacheslav Alekseevich

Dates

Publication Date

20260505

Application Date

20251222

Claims (1)

1. A method for producing isotropic coke, including coking the feedstock in a batch still with the production of coking distillates, characterized in that the feedstock, which is petroleum feedstock - heavy gas oil from catalytic cracking or coal feedstock - coal tar pitch with a softening temperature of up to 60 ° C, is mixed in a mixing tank with a polymer, which is polyacrylonitrile, in an amount of from 2.5 to 20% by weight, the resulting mixture of heavy gas oil from catalytic cracking with polyacrylonitrile or a mixture of coal tar pitch with polyacrylonitrile are sent to a batch still, where the mixture of heavy gas oil from catalytic cracking with polyacrylonitrile is heated to a temperature of 495-505 ° C, and the mixture of coal tar pitch with polyacrylonitrile - to a temperature of 510-520 ° C, at a rate of 110 degrees per hour and pressure from 0.3 to 0.4 MPa, with the production of green and pitch coke, as well as coking distillates containing a gasoline fraction, light and heavy coking gas oil, which are fed to the lower part of the distillation column for fractionation with the release of gas, which is sent for fractionation and purification, a gasoline fraction, light and heavy gas oil, while the gasoline and gas oil fractions are sent to obtain components of commercial fuels, and green and pitch coke is unloaded from the batch still and sent to a furnace for calcination in an inert nitrogen atmosphere at a temperature of at least 1300 ° C for one hour with the production of calcined coke of an isotropic structure with increased static strength of up to 12.6 MPa.

Description

The invention relates to a technology for obtaining coke raw materials for the production of carbon-containing materials, in particular coke of an isotropic structure with increased strength, used for the production of structural graphitized materials and products. A method for producing isotropic coke is known (RU Patent No. 2124037, published on 27.12.1998), which includes the pyrolysis of distillate fractions of NK-350°C from the coking process of heavy pyrolysis resin from the production of monoolefins and coking of the resulting hydraulic resin in cubes. The disadvantage of this method is the low coke yield, high process temperature, and the high probability of coking of the equipment when heating raw materials with a high content of polyaromatic hydrocarbons. A method is known for processing coal tar pitch by delayed coking (Terentyev A.A. Influence of coke structure on the quality of coke-pitch compositions based on them: dis. candidate of technical sciences: 05.17.11. - M., 2001. - 170 p.), which includes heating the raw material, which is non-mesophase high-temperature pitch with a softening temperature of 135-145 ° C, to a temperature of 740 ° C at a rate of no more than 3 degrees per minute with holding at the final temperature for 1 hour. The disadvantage of this method is the high yield of gases during cracking at high temperatures, low coke yield, and low structural strength of the resulting coke. A method for producing isotropic coke is known (RU Patent No. 2639904, published on 25.12.2017), which includes separating low-boiling fractions from heavy pyrolysis resin to form a soft pitch with a softening temperature of 30-80°C according to KIS, mixing it with carbon black in an amount of 2-10% of the mixture, processing the pitch mass in a disintegrator to obtain a homogeneous sedimentation-resistant dispersion, and coking the raw mixture in batch cubes at a temperature of 400-600°C. The disadvantage of this method is the dependence of the constancy of the physicochemical properties at different points of the final product on the efficiency of dispersion of carbon black throughout the volume of pitch, as well as the low mechanical strength of the resulting coke, associated with the addition of carbon black particles, which concentrate stresses in the resulting carbon matrix. A method is known for processing coal tar pitch for structural materials (RU Patent No. 2230770, published on 20.06.2004), which includes the initial heating of high-temperature pitch to a liquid state and subsequent carbonization of the pitch melt by raising the temperature to 550°C at a rate of no more than 20 degrees per hour from the temperature of the liquid state at 300°C to the temperature of the onset of carbonization and the formation of mesophase particles in an isotropic carbonized mass of pitch at 400°C, no more than 8 degrees per hour - to a temperature of 480°C, at least 50 degrees per hour - to a temperature of 550°C, at which fixation of the formed mesophase matrix is carried out by converting it into a solid state of semi-coke, normalization of the structure of the semi-coke by raising the temperature to 570-575°C at a rate of no more than 2 degrees per hour. The disadvantage of this method is the varying degree of ordering of the structure in the volume of coke obtained, associated with uneven heating at different points of the raw material at a given speed, high porosity of the coke due to gradual gas evolution during ultra-slow heating of the raw material and the associated low strength of the carbon material. A method for producing isotropic coke is known (Sabanenkov S.A., Rabinovich I.S., Seliverstov M.N. Production, properties and application of petroleum pyrolysis coke: thematic review. Series "Oil refining". Issue 9, TsNIITEneftekhim. - M., 1989, pp. 43-66), adopted as a prototype and including coking of hydraulic resin from the pyrolysis of low-sulfur straight-run kerosene gas oil fractions in batch stills with the production of isotropic coke of the KNPS type and coking distillates. The disadvantage of this method is the low coke yield, the need for additional preparation of raw materials, and the use of scarce straight-run fractions used for the production of motor fuels. The technical result is the production of coke with an isotropic structure and improved strength characteristics. The technical result is achieved by coking the feedstock in a batch still with the production of coking distillates, characterized in that the feedstock, which is petroleum feedstock - heavy gas oil of catalytic cracking or coal feedstock - coal tar pitch with a softening temperature of up to 60 °C, is mixed in a mixing tank with a polymer, which is polyacrylonitrile, in an amount of 2.5 to 20% by weight, the resulting mixture of heavy gas oil of catalytic cracking with polyacrylonitrile or a mixture of coal tar pitch with polyacrylonitrile is sent to a batch still, where the mixture of heavy gas oil of catalytic cra