RU2637699C1 - Coal charge for metallurgical coke production - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: for production of metallurgical coke coal charge contains the following components in a ratio, wt %: - sintering coals, including: - fat gas coal 13.0-18.0, - fat coal 3.0-16.0, - a mixture of fat gas + fat gas coal 2.0-6.0, with total amount of sintering coals 18.0-40.0; - coke coals, including: - coke coal 19.0-22.0, - fat coke coal 1.0-8.0, with total amount of coke coal 20.0-30.0; - depleted coals, including: - coke depleted coal 5.0-10.0, - low-caking coke 14.9-18.0, - depleted sintering coal 10.0-22.0, with total amount of coals 29.9-44.0; - granulated coal-tar pitch 0.1-5.0 - petroleum coke 0.1-6.0.

EFFECT: creation of charge with optimum sintering ability and coking ability to produce quality coke with reduced ash content, increased strength, increased coke yield.

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Description

The invention relates to by-product coke production, in particular to the composition of a coal charge for producing coke.

Known mixture for producing metallurgical coke (see AS SU 1703674 A1, IPC СВВ 57/04), including gas, fatty, coke and lean sintering coals, containing sintering additive - the remains of the process of heat treatment of sulphurous tar in the presence of iron ore concentrate at the following ratio of components in the mixture, mass. %:

- sintering additive (DM) 2.0-4.0; gas coals (G) 45.0-55.0; fatty coals (W) 17.0-25.0; coke coals (K) 10.0-15.0; lean sintering coals (OS) - the rest.

The disadvantages of the known composition include low coking ability, high yield of volatile substances, low yield of gross coke, high sulfur content, which, in turn, leads to an increase in the content of fine coke fraction 0-25 mm in gross coke, as well as to a decrease in cold and hot strength coke.

Known mixture of a special composition for producing blast furnace coke (see AS RU 2124548 C1, class C10B 57/04). The mixture of a special composition for producing blast furnace coke includes a mixture of fossil fuels of various technological types and a special additive, while it contains petrocoke fines as a special additive in the following ratio of components, mass. %:

- petrocoke fines 0.1-6.0

- a mixture of fossil fuels - the rest.

The disadvantages of the known charge include the lack of improvement in the quality characteristics of coke and a complex technological scheme for the preparation of the charge, which involves separate crushing of the components with their subsequent mixing in a centrifugal mixer.

There is a known mixture for producing coke, in which organic additives are actively introduced to increase sintering ability, which are actively involved in chemical reactions, improve their plastic properties, generating the formation of necessary compounds (see book: Promising directions for the development of coke production. Brown N.V., Glushchenko I.M.M .: Metallurgy, 1989, pp. 196-197). The mixture with the addition of coal tar pitch, depending on the ratios of other components during the experimental coking, has the following composition by weight:

- gas coal (G) from 66.7 in the base charge to 33.3;

- lean sintering coal (OS) from 33.3 to 16.7;

- coke coal (K) was absent in the base charge and was introduced during experimental coking from 20.0 to 50.0 mass. units;

- coal tar pitch (KP) was absent in the base charge and was introduced during experimental coking from 5 to 7.5 mass. units

The properties of the mixture changed as follows:

- yield of volatile V ^Daf ,% from 30.0 in the basic charge to 31.0 with the charge, in the composition of which coal tar pitch was used; - ash content Ad,% from 5.4 in the basic charge to 4.9-6.5 with the participation of coal tar pitch; - an expansion index from 1.5 in the base charge to 1.5-4.0 with the charge, in the composition of which coal tar pitch was used; - density, kg / m ³ - was not taken into account in the base charge, and in the charge, which included coal tar pitch, ranged from 699-725.

The properties of coke obtained by this technology are characterized by:

- an indicator of mechanical strength M 40 in the base charge 48.0, and 70.5-74.6 with the charge, which was used coal tar pitch;

- the abrasion index M 10 in the base charge 26.0 and 6.0-8.7 with the charge, which was used coal tar pitch.

The disadvantages of the obtained coal charge include low cokeability, a relatively high yield of volatile substances, which accordingly leads to a decrease in the cold and hot strength of coke, as well as to an increase in the reactivity of coke, and a low yield of gross coke.

A known mixture composition in which to increase the sinterability is used an organic additive - coal tar pitch, which is introduced into the mixture up to 8% (see Coke and Chemistry, 1982, No. 7. Authors: PF Gurtovnik, Yu.A. Larionov, etc. .) is the closest analogue. When this mixture has the following composition, mass. %:

- (D) gas coal 37.7-41.0; - (G) fat coal 26.7-29.0; - (K) coke coal 11.0-12.0; - (OS) thin-caked coal 12.0-13.0; - (T) lean coal 4.6-5.0.

The disadvantages of the charge of this composition, despite the insignificant positive effect of coal tar pitch on cold strength, include low coking ability, a relatively high yield of volatile substances, which, in turn, leads to high abrasion of coke, low cold and hot strength, low gross yield coke.

Known charge according to the patent of the Russian Federation No. 2444556, M. cl. СВВ 57/08 - prototype, including gas greasy, gas, lean sintering, coke coals and organic additive - coal tar pitch, while the mixture contains the following grades of coal in the indicated ratio, mass. %:

- gas greasy (GF) - 8.0-12.0: greasy + gas greasy (G + GF) - 9.0-19.0: gas (G) - 2.0-6.0: lean sintering + coke lean (OS + KO) - 5.0-10.0: coke lean (KO) 12.0-20.0: lean sintering (OS) - 10.0-14.0: weakly coking coke (C) - 15, 0-22.0: coke + lean coke (K + KO) - 4.0-8.0: coke (K) - 3.0-7.0: granular coal tar pitch 3.0-12.0, while use coal tar pitch granular fractions of 0.1-10 mm

The disadvantages of the charge of the prototype include a high level of yield of volatile substances, low yield of gross coke. Another disadvantage of this technical solution is the preparation of the mixture with dosing of coal tar pitch after separators in a fluidized bed, as a result of which coal tar pitch in the composition of the charge is present in the form of granules with a fraction of up to 10 mm.

The technical result of the invention is the creation of a mixture, optimal (improved) sintering and coking properties, to obtain high-quality coke with reduced ash content, increased mechanical and hot strength and increased yield of coke, including large.

The technical result achieved is achieved by using a combination of well-known features common to the prototype, including coals: - a mixture of greasy + gas greasy, gas greasy, coke, low caking coke, refined coke, sintering lean and organic additive - coal tar pitch and new signs, namely fat coals (G) in the amount of 3.0-16.0 masses are additionally introduced into the mixture. %, coke fat (QL) - 1.0-8.0 mass. % and petroleum coke, while the mixture contains the following components in the ratio, mass. %:

- sintering coals, including: - fatty gas (GF) - 13.0-18.0

- bold (W) - 3.0-16.0

- a mixture of fatty + gas fatty (W + GF) - 2.0-6.0

with a total number of sintering coals 18.0-40.0;

- coke coals, including:

- coke (K) - 19.0-22.0

- coke fat (QL) - 1.0-8.0

with the total amount of coke coal - 20.0-30.0;

- lean coals, including:

- coke lean (KO) - 5.0-10.0

- slightly coking coke (COP) - 14.9-18.0

- lean sintering (OS) - 10.0-22.0

with the total amount of coal burned - 29.9-44.0

- coal tar pitch, granular - 0.1-5.0

- petroleum coke - 0.1-6.0.

Petroleum coke is characterized by the following qualitative characteristics: yield of volatile substances in the range of 10.0-11.9%, sulfur content - not more than 3%, sinter index - not less than 8.0 units.

The novelty of the proposed coal charge for the production of metallurgical coke is that in the composition of the mixture additionally introduced coals of fat (W) in the amount of 3.0-16.0 mass. %, coke fat (QL) - 1.0-8.0 mass. % and petroleum coke, while the mixture contains the following components in the ratio, mass. %:

- sintering coals, including: - fatty gas (GF) - 13.0-18.0

- bold (W) - 3.0-16.0

- a mixture of fatty + gas fatty (W + GF) - 2.0-6.0

with a total amount of sintering coals - 18.0-40.0;

- coke coals, including:

- coke (K) - 19.0-22.0

- coke fat (QL) - 1.0-8.0

with the total amount of coke coal - 20.0-30.0;

- lean coals, including:

- coke lean (KO) - 5.0-10.0

- slightly coking coke (COP) - 14.9-18.0

- lean sintering (OS) - 10.0-22.0

with the total amount of coal burned - 29.9-44.0

- coal tar pitch, granular - 0.1-5.0

- petroleum coke - 0.1-6.0.

So, the introduction of the mixture of coal tar pitch in the amount of 0.1-5.0 mass. %, in combination with the introduction of the proposed grades of coke coals and petroleum coke in the amount of 0.1-6.0% into the coal charge, it allows to reduce the ash content of the coal charge and coke, provides optimal sintering and coking ability of the coal charge, to level the excessive fat content of the coal charge, which leads to an increase in the mechanical strength of coke while maintaining the coke's hot strength (CSR).

Reducing the amount of coal tar pitch additive makes it possible to level the excessive fat content of the coal charge.

A positive effect is also a decrease in the yield of volatile substances of the coal charge, which, in turn, leads to a decrease in the coal-coke consumption coefficient.

Signs of a charge in which petroleum coke is characterized by such qualitative characteristics as the yield of volatile substances in the range of 10.0-11.9%, sulfur content - not more than 3%, sintering index - not less than 8.0 units. - are additional signs that contribute to the achievement of the technical result.

The proposed coal charge for producing metallurgical coke is prepared as follows.

The mixture in the following ratio of components, mass. %:

- sintering coals, including: - fatty gas (GF) - 13.0-18.0

- bold (W) - 3.0-16.0

- a mixture of fatty + gas fatty (W + GF) - 2.0-6.0

with a total amount of sintering coals - 18.0-40.0;

- coke coals, including:

- coke (K) - 19.0-22.0

- coke fat (QL) - 1.0-8.0

with the total amount of coke coal - 20.0-30.0;

- lean coals, including:

- coke lean (KO) - 5.0-10.0

- slightly coking coke (COP) - 14.9-18.0

- lean sintering (OS) - 10.0-22.0

with the total amount of coal burned - 29.9-44.0

- coal tar pitch, granular - 0.1-5.0

- petroleum coke - 0.1-6.0

they are prepared at the charge feeding section, where the coals and additives that are part of the charge are crushed to the specified grinding (grade content 0-3.0 mm in the range 65-80%) using hammer crushers. The supply of coal tar pitch and petroleum coke to the charge is carried out from the silos of a closed coal warehouse through a dosing device, with a given content in the charge. The mixing of coal tar pitch and petroleum coke with coal is carried out in hammer crushers in the process of joint crushing. As a result, during joint crushing of coal tar pitch and petroleum coke in the composition of the charge, their uniform distribution with a uniform predetermined grinding of 0-3 mm is achieved.

The prepared charge is loaded into coke ovens using a coal-loading machine and coking is carried out.

In the future, operations to obtain finished coke are carried out according to well-known technology: heating and sintering without air access to a temperature of 1000-1100 ° C, coke dispensing, quenching, sorting and loading into wagons.

The first example of the composition of the coal charge

A mixture of the mixture in one of the variants of the composition was prepared by weighing in mass. % of each coal grade:

- sintering coals, including: - fatty gas (GF) - 15.0

- bold (F) - 8.0

- a mixture of fatty + gas fatty (W + GF) - 4.0

- coke coals, including:

- coke (K) - 21.0

- coke fat (QL) - 5.0

- lean coals, including:

- coke lean (KO) - 8.0

- low coking coke (COP) - 15.0

- lean sintering (OS) - 17.0,

then, coal tar granular in the amount of 3.0 masses was added to the coal mixture. % and petroleum coke in the amount of 4.0 wt. %

The mixture was prepared at the site of the charge supply, where the coals and additives that make up the mixture were crushed to a predetermined grinding (class content 0.0-3.0 mm in the range of 70-72%) using hammer crushers. The supply of coal tar pitch and petroleum coke to the charge was carried out from the silos of a closed coal warehouse through a dosing device with a given content in the charge. The mixing of coal tar pitch and petroleum coke with coal was carried out in hammer crushers in the process of joint crushing. As a result, during the joint crushing of coal tar pitch and petroleum coke in the composition of the charge, their uniform distribution with a uniform specified grinding of 0-3 mm was achieved. The prepared charge was loaded into coke ovens using a coal-loading machine and its coking was carried out.

Subsequently, operations to obtain finished coke were carried out according to the well-known technology: heating and sintering without air access to a temperature of 1000-1100 ° C, coke delivery, quenching, sorting and loading into cars.

The second example of the composition of the coal charge

The proposed coal charge for producing metallurgical coke is obtained as follows.

The mixture in the following ratio of components, mass. %:

- sintering coals, including: - fatty gas (GF) - 18.0

- bold (F) - 9.0

- mixture fatty + gas fatty (F + GF) - 2.5

- coke coals, including:

- coke (K) - 20.5

- coke fat (QL) - 6.5

- lean coals, including:

- coke lean (KO) - 5.0

- slightly coking coke (COP) - 18.0

- lean sintering (OS) - 14.0.

Then, coal tar pitch granulated in an amount of 1.0 mass was added to the coal mixture. % and petroleum coke in the amount of 5.5 wt. % The mixture was prepared at the site of the charge supply, where the coals and additives that make up the mixture were crushed to a predetermined grinding (class content 0.0-3.0 mm in the range of 70-72%) using hammer crushers. The supply of coal tar pitch and petroleum coke to the charge was carried out from the silos of a closed coal warehouse through a dosing device with a given content in the charge. The mixing of coal tar pitch and petroleum coke with coal was carried out in hammer crushers in the process of joint crushing. As a result, during the joint crushing of coal tar pitch and petroleum coke in the composition of the charge, their uniform distribution with a uniform specified grinding of 0-3 mm was achieved. The prepared charge was loaded into coke ovens using a coal-loading machine and its coking was carried out.

Subsequently, operations to obtain finished coke were carried out according to the well-known technology: heating and sintering without air access to a temperature of 1000-1100 ° C, coke delivery, quenching, sorting and loading into cars.

Coke from the specified charge was extinguished using dry quenching. At the same time, coke obtained from this mixture was characterized by a high level of strength characteristics. So, the mechanical strength (M25) was 87.9%, the strength of coke after the reaction with CO ₂ (CSR) was 66.1%, the ash content was 10.1%, which meets the international requirements for coke quality standards, including coke quality for blast furnaces using pulverized coal injection technology.

The third example of the composition of the charge for coking

The proposed coal charge for producing metallurgical coke was obtained as follows.

The mixture in the following ratio of components, mass. %:

- sintering coals, including:

- gas fatty (GF) - 13.5

- bold (F) - 9.0

- mixture fatty + gas fatty (F + GF) - 6.0

- coke coals, including:

- coke (K) - 19.0

- coke fat (QL) - 8.0

- lean coals, including:

- coke lean (KO) - 5.0

- low coking coke (COP) - 16.0

- lean sintering (OS) - 19.9,

then, coal tar granulated in the amount of 1.6 masses was added to the coal mixture. % and petroleum coke in an amount of 2.0 wt. % The mixture was prepared at the site of the charge supply, where the coals and additives that make up the mixture were crushed to a predetermined grinding (class content 0.0-3.0 mm in the range of 70-72%) using hammer crushers. The supply of coal tar pitch and petroleum coke to the charge was carried out from the silos of a closed coal warehouse through a dosing device with a given content in the charge. The mixing of coal tar pitch and petroleum coke with coal was carried out in hammer crushers in the process of joint crushing. As a result, with the joint crushing of coal tar pitch and petroleum coke in the composition of the charge, their uniform distribution with a uniform specified grinding of 0-3 mm was achieved. The prepared charge was loaded into coke ovens using a coal-loading machine and its coking was carried out.

Subsequently, operations to obtain finished coke were carried out according to the well-known technology: heating and sintering without air access to a temperature of 1000-1100 ° C, coke delivery, quenching, sorting and loading into cars.

Coke from the specified mixture was extinguished using "wet" quenching. At the same time, coke obtained from this mixture was characterized by a high level of strength characteristics. Thus, the mechanical strength (M25) was 85.5%, the coke strength after reaction with CO ₂ (CSR) was 62.0%, and the ash content was 10.8%, which corresponded to high quality levels.

At present, the enterprise has developed technological documentation for the charge of the proposed composition, conducted experimental and pilot industrial work on the production of coke, and obtained positive results.

In all tested experimental compositions of coal mixtures containing a mixture of coal and pitch coal in an amount of from 1% to 5 mass. %, with the introduction of petroleum coke in an amount of up to 6 mass. % there was a decrease in the ash content of the coal charge to 0.5%, metallurgical coke to 0.6-0.7%, the yield of volatile substances from the charge to 0.3-0.4%.

The increase in sulfur content occurred in the tolerances of the values established in TU 1104-076100-00190437-159-96. "Metallurgical coke from coals of the eastern regions."

The strength characteristics of coke by hot strength did not change with the introduction of petroleum coke, a high level of values (more than 60%) was maintained. In terms of mechanical strength (M25) and abrasion resistance (M10), a tendency toward an increase in quality was recorded, due to the above reasons. Indicators of mechanical strength (M25) increased by 0.4%, while abrasion (M10) decreased by 0.2-0.3%.

Claims (18)

1. Coal charge for producing metallurgical coke, including coals - a mixture of greasy + gas greasy, gas greasy, coke, low-coking coke, coke lean, sintering lean and organic additive - coal tar pitch, characterized in that coals are added to the charge in combination with greasy ( G) in an amount of 3.0-16.0 mass. %, coke fat (QL) - 1.0-8.0 mass. % and petroleum coke, while the mixture contains the following components in the ratio, mass. %: - sintering coals, including: - gas fatty (GF) - 13.0-18.0 - bold (W) - 3.0-16.0 - a mixture of fatty + gas fatty (W + GF) - 2.0-6.0 with a total number of sintering coals 18.0-40.0; - coke coals, including: - coke (K) - 19.0-22.0 - coke fat (QL) - 1.0-8.0 with the total amount of coke coal - 20.0-30.0; - lean coals, including: - coke lean (KO) - 5.0-10.0 - slightly coking coke (COP) 14.9-18.0 - lean sintering (OS) - 10.0-22.0 with the total amount of lean coals - 29.9-44.0; - coal tar pitch, granular - 0.1-5.0 - petroleum coke - 0.1-6.0. 2. The mixture according to claim 1, characterized in that the petroleum coke is characterized by the following qualitative characteristics: yield of volatile substances in the range of 10.0-11.9%, sulfur content - not more than 3%, sintering index - not less than 8.0 units .