RU2330872C1 - Method of low-sulphur oil coke production - Google Patents

Abstract

FIELD: petrochemical industry.

SUBSTANCE: invention refers to petrochemical industry, particularly to treatment of black oil in the process of delayed coking. The method of low-sulphur oil coke production is performed by means of delayed coking of a mixture consisting of petrochemical and/or oil processing black oil; at that 10-25% of a hydro refined gasoline fraction of liquid coke products, preliminary heated up to 200-300°C, is added into black oil or into the mixture.

EFFECT: invention facilitates production of a low sulphur coke implementing a low cost process due to a selection of a used mixture composition and due to excluding the stage of a coke hydrogen treatment under increased pressure.

9 ex, 1 tbl, 1 dwg

Description

Technical field

The invention relates to the refining industry, and in particular to the technology of processing heavy oil residues in the process of delayed coking, and is aimed at improving the properties of the resulting petroleum coke.

State of the art

A known method of producing petroleum coke, including the manufacture of a mixture of petroleum residues, its preliminary heating to 300-400 ° C, mixing with steam-gas coking products in the still bottom of the distillation column, heating the resulting mixture (secondary coking feedstock) to 480-510 ° C, keeping it in a coking reactor for 16-48 hours to produce coke and a light fraction of coking and subsequent distillation of a light fraction (Akhmetov S.A. Technology for the deep processing of oil and gas: Textbook for universities. Ufa: Gilem, 2002, p. 383-390 ) This method of delayed coking of oil residues is used in almost all existing coking plants in Russia.

The main indicators of the quality of petroleum coke are the sulfur content, trace metals, ash, moisture, volatiles yield, particle size distribution and mechanical strength. Depending on the proportion of sulfur, cokes are classified as low sulfur (1-1.15 wt.%), Sulfur (1.6-4.0 wt.%) And high sulfur (more than 4 wt.%). The increased sulfur content in cokes causes corrosion of equipment, an increased number of cracks in electrode products, a decrease in the grade of metals and environmental problems.

The raw materials for processing at delayed coking plants are various oil residues - tars obtained by vacuum distillation of fuel oil; fuel oil obtained by atmospheric distillation of oil; asphalt; oil by-products; heavy catalytic cracking gas oil; heavy pyrolysis resin.

For the production of low sulfur petroleum coke (electrode coke), aromatic hydrocarbon concentrates are traditionally used in the world practice, having a low sulfur content, low ash content, low content of substances insoluble in benzene and quinoline. These qualities are possessed by distillate cracking residues (DKO) from low-sulfur oils, catalytic cracking gas oil (GKK), pyrolysis oil refining products and oil extracts.

Practice shows that the quality of petroleum coke depends both on the quality of the individual petroleum residues used and on the component composition of the mixtures. Therefore, the task of improving the quality of petroleum coke in conditions of a shortage of low-sulfur coking feedstock is solved by selecting the optimal composition of coking feedstock (compounding) and using the technology for preparing coking feedstock.

By compounding sulfur and low sulfur oil residues in the coking feed, it is possible to not only reduce the content of sulfur, metals and coke fines in coke, but also increase the yield of coke.

Closest to the claimed object is a method for producing petroleum coke (RF patent No. 2079537, СВВ 55/00), which consists in the fact that a mixture of heavy oil residues of petrochemicals and / or oil refining, in particular a mixture of distillate cracked residue and tar, is fed into the chamber delayed coking, after which the resulting product is treated with hydrogen at a temperature of 490 - 550 ° C and pressure up to 5 MPa for 8-24 hours.

The disadvantage of this method of obtaining low sulfur coke is the high cost caused by the use of hydrogen.

Disclosure of invention

The problem solved by the claimed invention is to develop a low-cost technology for producing low sulfur coke.

The technical result consists in the fact that due to the choice of the composition of the mixture used, the stage of treating coke with hydrogen at elevated pressure to obtain low-sulfur coke is eliminated.

The technical result is achieved by delayed coking of a mixture of heavy oil residues of petrochemicals and / or refining, in which add 10-25% hydrotreated gasoline fraction of liquid coking products, preheated to 200-300 ° C.

The implementation of the invention

The drawing shows a schematic flow diagram of a delayed coking unit.

A method of obtaining low sulfur petroleum coke from oil residues is as follows. The coking feedstock made by mixing oil residues in the mixer 1 is heated in the convection coils of the furnace 2 to 300-400 ° C and enters the distillation column 3, where the coking feed is prepared; coking products coming from the coke reactor 4 with a temperature of 360-430 ° C under the lower cascade plate of the distillation column are in contact with the feedstock; high-boiling components found in coking products, as a result of contact with the feedstock, condense and return to the coking mixture with the feedstock. The secondary raw materials thus prepared via the transfer line, where, through a special input unit 5, is supplied (injection) of a portion of the hydrotreated gasoline fraction of the delayed coking liquid products that is preheated to 200-300 ° C, enters furnace 2, where it is heated to the coking temperature of 460-510 ° C, and then to the coke reactor 4. The distillate coking products formed during coking through the top of the coke reactor 4 enter the bottom of the distillation column 3 under the cascade plates, where the raw materials are prepared coking, as well as the separation of coking products into heavy delayed coking gas oil, delayed coking light gas oil, delayed coking gasoline fraction and gas. Coke formed during the decomposition of a mixture of oil residues fills the coke reactor 4. When the coke reactor is filled with coke by 70-80%, superheated or hot steam is fed to it for steaming the coke, after which coke is cooled and unloaded from the coke reactor 4.

The supply of a hydrotreated gasoline fraction of liquid coking products heated to 200-300 ° C to a transfer line with secondary coking feed obtained by mixing coking products with the feed at the bottom of the distillation column eliminates the stage of treating coke with hydrogen at elevated pressure and thereby ensures low sulfur content coke using low-cost technology.

Below are examples of the production of coke by the proposed method.

Example 1. To 50.0 g of coking feed consisting of GK-3 tar (sulfur content 1.38 wt.%) Was added 5.6 g of hydrotreated gasoline fraction of the liquid products of the delayed coking process (sulfur content 0.1%), previously heated to 200 ° C. As a result of the process of delayed coking of the prepared mixture, 13.62 g of petroleum coke was obtained with a sulfur content of 1.11 wt.%.

Example 2. To 50.0 g of coking feed consisting of GK-3 tar (sulfur content 1.38 wt.%) Was added 8.8 g of hydrotreated gasoline fraction of the liquid products of the delayed coking process (sulfur content 0.1%), previously heated to 250 ° C. As a result of the process of delayed coking of the prepared mixture, 12.34 g of petroleum coke with a sulfur content of 1.05 wt.% Were obtained.

Example 3. To 50.0 g of coking feed consisting of tar GK-3 (sulfur content 1.38 wt.%) Was added 16.7 g of hydrotreated gasoline fraction of the liquid products of the delayed coking process (sulfur content 0.1%), previously heated to 300 ° C. As a result of the process of delayed coking of the prepared mixture, 12.67 g of petroleum coke with a sulfur content of 1.00 wt.% Were obtained.

Example 4. To 50.0 g of a raw material mixture consisting of ELOU AVT-6 tar and GK-3 tar (sulfur content 1.43 wt.%) Was added 5.6 g of hydrotreated gasoline fraction of the liquid products of the delayed coking process (sulfur content 0 , 1%), preheated to 200 ° C. As a result of the process of delayed coking of the prepared mixture, 13.86 g of petroleum coke with a sulfur content of 1.29 wt.% Were obtained.

Example 5. To 50.0 g of a raw material mixture consisting of ELOU AVT-6 tar and GK-3 tar (sulfur content 1.43 wt.%) Was added 8.8 g of hydrotreated gasoline fraction of delayed coking liquid products (sulfur content 0 , 1%), preheated to 250 ° C. As a result of the process of delayed coking of the prepared mixture, 12.94 g of petroleum coke was obtained with a sulfur content of 1.22 wt.%.

Example 6. To 50.0 g of the raw material mixture consisting of ELOU AVT-6 tar and GK-3 tar (sulfur content 1.43 wt.%) Was added 16.7 g of hydrotreated gasoline fraction of delayed coking liquid products (sulfur content 0 , 1%), preheated to 300 ° C. As a result of the process of delayed coking of the prepared mixture, 12.00 g of petroleum coke with a sulfur content of 1.09 wt.% Were obtained.

Example 7. To 50.0 g of a feed mixture consisting of GK-3 tar and heavy pyrolysis resin (sulfur content 1.29 wt.%), 5.6 g hydrotreated gasoline fraction of the liquid products of the delayed coking process (sulfur content 0.1 %), preheated to 200 ° C. As a result of the process of delayed coking of the prepared mixture, 14.46 g of petroleum coke with a sulfur content of 1.22 wt.% Were obtained.

Example 8. To 50.0 g of a feed mixture consisting of GK-3 tar and heavy pyrolysis resin (sulfur content 1.29 wt.%) Was added 8.8 g of hydrotreated gasoline fraction of the liquid products of the delayed coking process (sulfur content 0.1 %), preheated to 250 ° C. As a result of the process of delayed coking of the prepared mixture, 13.82 g of petroleum coke was obtained with a sulfur content of 1.16 wt.%.

Example 9. To 50.0 g of a raw material mixture consisting of tar GK-3 heavy pyrolysis resin (sulfur content 1.29 wt.%) Was added 16.7 g of hydrotreated gasoline fraction of the liquid products of the delayed coking process (sulfur content 0.1% ) preheated to 300 ° C. As a result of the process of delayed coking of the prepared mixture, 13.34 g of petroleum coke was obtained with a sulfur content of 1.04 wt.%.

The test results of samples of petroleum coke obtained by delayed coking of compounded raw materials, differing in component composition in accordance with examples 1-9, are shown in the following table.

Table Way The composition of the raw mix * Coke yield,% Sulfur content, wt.% in raw materials in coke Prototype G + TGKK + TPS 28.0 1.45 1.42 Example 1 GGK-3 + 10% Bf 24.5 1.25 1,11 Example 2 GGK-3 + 15% Bf 21.0 1.18 1.05 Example 3 GGK-3 + 25% Bf 19.0 1.06 1.00 Example 4 GAVT-6, GGK-3 + 10% Bf 25.0 1.30 1.29 Example 5 GAVT-6, GGK-3 + 15% Bf 22.0 1.23 1.22 Example 6 GAVT-6, GGK-3 + 25% Bf 18.0 1.10 1.09 Example 7 GGK-3 + TPS + 10% Bf 26.0 1.18 1.22 Example 8 GGK-3 + TPS + 15% Bf 23.5 1.12 1.16 Example 9 GGK-3 + TPS + 25% Bf 20,0 1,03 1,04 * - G - tar; THCK - heavy catalytic cracking gas oil; TPS - heavy pyrolysis resin; GAVT-6 - tar ELOU AVT-6; GGK-3 - tar GK-3; Bf - gasoline fraction.

Industrial applicability

The invention can be used in the refining industry, namely in the production of petroleum coke in the processing of heavy oil residues in the process of delayed coking, to improve the quality of the obtained petroleum coke.

Claims (1)

A method for producing low-sulfur petroleum coke by delayed coking of a mixture of heavy petroleum residues of petrochemicals and / or refining, characterized in that a heavy petroleum residue or a mixture of heavy petroleum residues with the addition of 10-25% hydrotreated gasoline fraction of liquid coking products preheated to 200-300 is used ° C.