RU2636514C1 - Additive to charges for manufacturing metallurgical coke - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: mixture of coal tar pitch with petroleum semi-coke with a yield of volatile substances of 12-27%, sulfur content up to 4.8%, a temperature range of ductility in the range of 50-100°C at the ratio from 1.0 to 10.0 to 1.0 to 2.5 is used as an additive-substitute for at least one of the group of charge coals in the production of metallurgical coke.

EFFECT: universal properties which can replace different groups of coals in the charge in the production of metallurgical coke, depending on the ratio of the coal tar pitch and petroleum semi-coke.

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Description

The present invention relates to the field of production of metallurgical coke and can be used in metallurgy, in particular at coke plants.

It is known to obtain foundry coke from a coal charge with the participation of semi-coke fines during research at Altai-Koks to develop and improve the technology for producing foundry coke of improved quality. At the same time, a thinning additive, a semi-coke trifle, was introduced into the composition of the coal charge. See Cox's article. Chemistry, 1997. No. 2. UDC 662.749.001.5, authors: cand. tech. sciences V.M. Strakhova (Kuznetsk branch of VUKHIN), Ph.D. tech. sciences O.G. Unterberger, N.V. Kapustina (VUKHIN), V.V. Kochkina, P.P. Chancellor and B.C. Prosvirova (Altai-Koks JSC).

With the introduction of 1 and 3% semi-coke into the charge, the coke size increased, the average piece size increased from 69.56 in the initial coke to 71.17 and 72.68%, and the content of the large class over 60 mm increased from 75.2 to 79.8 respectively and 76.8%. At the same time, the mechanical strength of coke increased.

The disadvantages of producing foundry coke using semi-coke fines are the increased ash content of the charge and, as a result, the increased ash content of metallurgical coke, as well as the increased reactivity of coke.

Known patent of the Russian Federation No. 2224782 "charge for producing metallurgical coke", according to which in an appropriate ratio contains fatty, gas-fatty coke low-sintering coals, lean sintering coals and sintering additive. Sintering additive was obtained by mixing a pecky product with plastic waste in a certain ratio, heating this mixture to a temperature of 300-350 ° C for 0.5-1.0 hours.

Obtaining this mixture is effective from the point of view of recycling plastic waste, but the disadvantage of the known solution lies in the need to prepare a sintering additive for a certain time, this factor complicates the technology for preparing the mixture.

Known more effective coking additive according to the patent of the Russian Federation No. 2355729 - a prototype in the form of the use of petroleum coke with a yield of volatiles in the range of more than 14% and less than 25% as a coking additive to coal blends used for the production of metallurgical coke.

EFFECT: replacement of severely deficient coal of brand K with a cheap associated product - petroleum coke; utilization of petroleum coke and cost reduction of the coking process. In addition, according to the authors and the applicant of the said patent, the use of petroleum coke, while maintaining the coking and sintering properties of the additive at the required level, ensured a reduction in the volatiles content in the charge as compared with coking additives with a volatiles content in the range from 25 to 35%, improving accordingly charge quality.

However, replacing K-grade coal with a low-cost by-product - petroleum coke is not an equivalent substitute for the following reasons: - when the K components are completely or partially replaced by a coking additive in the composition of the blend - petroleum coke significantly reduces the quality of coke in terms of sulfur content, and reduces the yield volatile substances of the charge to critical values, creating risks when conducting technological processes (drilling a furnace).

The technical result of the invention is the creation of an additive - a substitute for charge coal in the production of metallurgical coke, which provides for the replacement of at least one type of coal in the composition of the charge, which allows for high cokeability of the charge, low sulfur content in the final product and an increase in the quality of coke in terms of coke strength (CSR ) and reactivity (CRI). An additional technical result is the expansion of technological capabilities for the production of coke associated with the unhindered release of coke from coking chambers and lower costs for the production of coke using known components for a new purpose.

The technical result set by the invention is achieved by using a mixture of coal tar pitch with petroleum semi-coke with a yield of volatiles of 12-27%, a sulfur content of up to 4.8%, a temperature range of ductility in the range of 50-100 ° C in a ratio from 1.0 to 10.0 up to 1.0 to 2.5 - peconeftecox, as an additive substitute for at least one of the group of coals of the mixture in the production of metallurgical coke.

Coal tar pitch is a solid product of the processing of coal tar (yield 50-60% by weight). Black in appearance thermoplastic substance with a shiny conchoid fracture. Elemental composition (%): 92-93 C, 4.3-4.7 H, 0.3-0.85 S, 1.7-1.8 N, 0.8-1.0 O. Density 1, 2-1.3 g / cm ³ , ash content 0.2-0.3%, volatile yield 50-63%, sulfur content up to 0.65 (according to Altai-Koks OJSC). At the same time, granular coal tar pitch is used to obtain peconeftecox.

Petroleum semi-coke is a product obtained by semi-coking of heavy oil residues without access of air at a temperature not exceeding 550 ° C.

The use of a mixture of coal tar pitch and petroleum coke as a component of the charge, which provides the replacement of at least one type of coal in the composition of the charge and allows for high cokeability of the charge, low sulfur content in the final product and an increase in the quality of coke in terms of coke strength (CSR) and reactivity (CRI), it is not known from the identified technical solutions, which allows us to attribute the features of the proposed facility to those with novelty, and in combination with quantitative characteristics and achieve the expected positive result - to those who have an inventive step.

A description of the process for producing an additive as a substitute for charge coal in the production of metallurgical coke, the conducted experimental work of producing coke with higher operational characteristics make it possible to attribute the proposed essential features of the invention to industrially feasible.

The specified mixture of coal tar pitch and petroleum coke has sufficient coking ability - against pitch, low sulfur content - against petroleum coke and the release of volatile substances that shrink the coke cake to a level that does not lead to increased force when the coke cake is discharged from the furnace.

The proposed additive - peconeftecox has universal properties, which, depending on the ratio of the pitch of coal and petroleum coke, replace different coal groups in the charge for the production of metallurgical coke.

To test the feasibility of replacing at least one type of coal in the composition of the charge with the proposed additive, experimental work was carried out using an additive in the charge replacing with a different quantitative ratio of coal tar pitch to petroleum semi-coke - from 1.0 to 10.0 to 1.0 to 2 ,5.

Initially, for the charge of the required composition, a replacement additive is prepared - a mixture of coal tar pitch and petroleum coke. To do this, in a certain ratio carry out the mixing of petroleum coke with tar pitch. The additive is prepared by uniformly dispensing each of the two products from the coal receiving hoppers onto the conveyor belt, followed by mixing in the transfer chutes during transportation to the silo of the closed coal storage. The new additive has sufficient coking properties, an increased yield of volatile substances and a low sulfur content.

The use of a new additive - peconeftecox as part of a coal charge for the production of coke makes it possible to obtain metallurgical coke with high quality indicators in terms of M25, CSR / CRI, low sulfur content and sufficient shrinkage of coke cake to ensure unhindered coke dispensing from coking chambers.

As a result of the work carried out, it was concluded that with an increase in the participation of pitch in peconeftecox, there is a decrease in sulfur content, an increase in the yield of volatile substances, the sintering properties of the additive are improved, which allows it to be used to replace the coals of sintering groups (grade G, GZ) with the introduction of coking properties . With a decrease in the share of pitch in peconeftecox, a decrease in the yield of volatiles occurs, accompanied by an increase in the yield of gross coke, an improvement in coking properties, which makes it possible to use peconefecox to replace coals of coke and depletion groups.

Thus, as a result of experimental work, it was found that when using a ratio of pitch to oil semi-coke of 1.0 to 10.0, the pecone oil coke sintering index, determined according to GOST ISO 15585, was 65 units, the yield of volatile substances was 18.5%. When using this peconeftecox in the composition of the coking charge as a substitute for part of the coke and exhaust group coals, the coke hot strength index (CSR) increased by 1.7%, the coke reactivity (CRI) decreased by 1.1% relative to the charge variant, not containing peconeftecox. When using the ratio of pitch to petroleum semi-coke 1 to 2.5, the sintering index was 100 units, the yield of volatiles was 25.6%, which made it possible to consider peconeftecox as a substitute for coals of the sintering group. When using this peconeftecox in the composition of the coking charge, an increase in the coke hot strength index (CSR) by 4.3%, a decrease in the reactivity (CRI) of coke by 1.9%, relative to the charge-free pecone oil coke variant. Those. with each new ratio of coal tar pitch to petroleum semi-coke, a final product was obtained - coke with the required performance characteristics for coke strength (CSR) and reactivity (CRI).

Currently, the company has conducted a series of studies on the replacement of certain types of coal with the proposed additive and positive results have been obtained.

Claims (1)

 The use of a mixture of coal tar pitch with petroleum coke with a yield of volatiles of 12-27%, a sulfur content of up to 4.8%, a temperature range of ductility in the range of 50-100 ° C in a ratio of 1.0 to 10.0 to 1.0 to 2 , 5 - peconeftecox, as an additive substitute for at least one of the group of coals of the mixture in the production of metallurgical coke.