RU2448146C2 - Mixture for producing blast-furnace coke - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: mixture for producing blast-furnace coke contains the following, wt %: fat or gas fat coal 25-65 and low-caking coking coal or lean coking coal 35-75. In another version, the mixture contains the following, wt %: fat coal 25-40, low-caking coking coal 35-60 and lean coking coal 5-35. The mixture can also contain the following, wt %: gas fat coal 30-55, low-caking coking coal 30-60 and lean coking coal 5-20; or fat coal 35-40, gas fat coal 5-15 and low-caking coal 50-55; or fat coal 10-30, gas fat coal 20-30, low-caking coking coal 20-60 and lean coking coal 5-25. The disclosed mixtures have characteristics which are as good as characteristics of high-quality coking and fat coking coal, specifically free swell index FSI from 5 to 7 arbitrary units and vitrinite reflectance R₀ (1.15-1.25)%.

EFFECT: preparing of said mixtures does not require additional process operations and widens the raw material base for producing high-quality coke.

6 cl, 1 tbl

Description

The invention relates to coke production, in particular to compositions for the manufacture of metallurgical coke.

Coking coals are characterized by high sintering ability, characterized by an index of free expansion - FSI, and a low yield of volatile substances or a high reflectivity of vitrinite - R ₀ , causing a high yield of coke. Initially, such coals were coke grades - K and fatty coke - KZh. However, at present, due to the depletion of coking coal grades of grades K and KZh, it is necessary to use mixtures of ordinary coals of various grades.

Various compositions of charge mixtures from coals of various grades for producing coke are known. Most often, to improve the sintering ability of the mixtures, various additives are used in them, such as coal sands, oil tar and sands, crushed rubber and other additives.

So, according to the patent of the Russian Federation No. 2144548, СВВ 57/04, publ. 01/10/1999, petrocoke fines, prepared according to a special technology, are added to a coal mixture with a reduced amount of well-sintering component.

In the charge used in the method described in the patent of the Russian Federation No. 2135543, СВВ 53/08, СВВ 57/08, publ. 08/27/1999, containing coals of the grades: gas, fatty, lean sintering and low-ash, low-sintering coals, an additive of phthalopec-containing waste of coke production was used.

According to the patent of the Russian Federation No. 2186823, С10В 57/06, СВВ 53/08, publ. 08/10/2002 in the mixture containing coals of different grades: gas-fat and fatty, coke, lean - low-caking and coke - low-caking, add an additive from the waste of coke production, deposited on the rubber crumb of waste rubber products.

However, the use of additives requires special preparation, and also complicates the technology of preparation of charge mixtures. In addition, it is known that pecks are currently fully used in the electrode industry, and are scarce and expensive. Petroleum products are also expensive raw materials. The use of rubber introduces an additional amount of sulfur, the content of which in coke is limited.

The mixture closest to the mixture proposed by composition of coals is a mixture for producing metallurgical coke (RF patent No. 2224782, IPC СВВ 57/04, publ. 02.27.2004), containing coal grades:

fatty 20-30

gas-fat coals 15-20

low coking coke 20-40

thinner-sintering, as well as including a sintering additive made from a pitch product obtained by special technology from coal with an additive that is mixed with plastic waste.

The main disadvantage of the mixture of this composition is the need to use sintering additives, complicating the manufacturing technology and increasing the cost of obtaining the mixture.

The basis of the invention is the task of obtaining the composition of the mixture with the optimal ratio of components from ordinary coals of various grades for the production of high-quality coke without the use of additives.

The technical result achieved by the implementation of the claimed invention is the simplification and cheapening of the technology of preparation of the charge, as well as the expansion of the raw material base for receiving the charge.

The technical result is achieved by the fact that the following options for the composition of the charge:

charge for producing metallurgical coke containing fatty (G) or gas-fatty (GF) and low-coking coke (KS) coals, in which coals are introduced in the following ratio of components, wt.%:

fatty or gas-fatty coals 25-65,

low coking coals 35-75;

charge for producing metallurgical coke containing fatty or gas-fatty coals, which additionally contains coke lean (CO) coals in the following ratio of components, wt.%:

fatty or gas-fatty coals 25-65,

coke lean coals 35-75,

with the exception of the following ratios of components, wt.%:

fatty or gas-fatty coals 40,

coke lean coals 60;

fatty or gas-fatty coals 50,

coke lean coals 50;

fatty coals 60,

coke lean coal 40;

charge for producing metallurgical coke containing fatty and coke low-sintering coals, which additionally contains coke lean coals in the following ratio of components, wt.%:

fatty coals 25-40,

coking low-sintering coals 35-60,

coke lean coals 5-35;

charge for producing metallurgical coke containing gas-fatty and coke low-sintering coals, which additionally contains coke lean coals in the following ratio of components, wt.%:

gas-fatty coals 30-55,

low coking coals 30-60,

coke lean coals 5-20;

charge for producing metallurgical coke containing fatty, gas-fatty and low-coking coking coals, in which coals are introduced in the following ratio of components, wt.%:

fatty coals 35-40,

gas-fat coals 5-15,

low coking coals 50-55;

charge for producing metallurgical coke containing fatty, gas-fatty and coke low-caking coals, which additionally contains coke lean coals in the following ratio of components, wt.%:

fatty coals 10-30,

gas-fatty coals 20-30,

low coking coals 20-60,

coke lean coals 5-25.

In the experimental selection of the composition of the mixture with the optimal ratio of the components, the property of coals of various grades was used to strengthen the sintering properties of each other by finding the optimal ratio of free expansion index - FSI and reflectance of vitrinite - R ₀ , required for the production of high-quality coke. Mixtures of coals of various grades having an FSI index of 5-7 and a value of R ₀ 1.15-1.25%, corresponding to the characteristics of coke and coke fat coals, have satisfactory qualities for producing coke.

The quantitative ratios of the components in the mixture variants are selected so that they satisfy the above conditions (see table). To ensure greater freedom of choice in the preparation of mixtures, the approach of compensating the properties of one component by replacing it with two other components in combination was used.

With a two-component mixture of W and KS, the best sintering behavior is obtained, but the cost of the mixture increases and the maximum value of R _{0 is} difficult to achieve.

A mixture of two coals GJ and KS has a lower cost, but worse sintering ability and a lower value of R ₀ .

The mixture of the three components GJ, KS and KO has a greater value of R ₀ . But its sintering ability is low, which narrows the area of use of the obtained coke.

A mixture of the other three components W, KS and KO has good sintering ability, has a greater value of R ₀ . But it is more expensive than the previous mixture.

A mixture of four components GZH, G, KS and KO allows to obtain a sufficiently high sintering ability and R ₀ values, changing the ratio of components. But at the same time, the process of preparing the mixture is somewhat complicated.

At the same time, the preparation of all types of mixtures described above does not require additional technological operations at coke plants, unlike other methods of preparation and composition of mixtures. Therefore, the given compositions of coking mixtures allow one to obtain high-quality coke and significantly expand the raw material base for producing a charge.

An example of the preparation of the charge mixture

The coking mix is prepared from ordinary grade Zh coal mined at the Chertinskaya-Koksovaya mine and ordinary grade KO coal mined at the Novobachatsky open pit. Ordinary coals from ordinary coal silos at the Belovskaya Central Processing Plant are dosed to the collecting conveyor layer by layer in the proportion of 25% of grade Zh coal and 75% of grade KO. The two-layer mixture obtained on the conveyor is fed to primary crushing to a fineness of less than 200 mm and then to hydroclassification, where the class is separated by a fineness of less than 0.5 mm and transferred to flotation. The class size of 13-200 mm is fed to enrichment in heavy-medium separators. A class of 0.5-13 mm is fed to enrichment on jigging machines. Concentrates from jigging machines and flotation are fed together for drying. After drying, the concentrate is mixed on a collection conveyor with concentrate from heavy-medium separators that have been dehydrated on vibrating screens. The mixture of concentrates has a ratio of grades Zh and KO equal to 30:70, taking into account the degree of enrichment of each brand. The finished mixture has a vitrinite reflectance of 1.20%, a free expansion index of 6, and a plastic layer thickness of 17 mm, which makes it suitable for coking both independently and in a mixture with other coals.

Other examples of the preparation of the mixture, performed in a similar way, with quantitative values of the components for the options shown in the table.

Table No. Examples The composition of the mixture,% Quality indicators F The cop GZ KO Free expansion index, FSI, units The reflectivity of vitrinite R ₀ ,% one 0 35 65 0 6 1.15 2 0 75 25 0 5 1.20 3 25 75 0 0 5 1.25 four 65 35 0 0 7 1.15 5 65 0 0 35 7 1.15 6 0 0 25 75 5 1.20 7 0 0 65 35 6 1.15 8 25 60 0 fifteen 5 1.25 9 40 35 0 25 6 1.15 10 25 40 0 35 5 1.20 eleven 35 60 0 5 5 1.20 12 0 60 35 5 5 1.20 13 0 35 55 10 5½ 1.15 fourteen 0 thirty 55 fifteen 5½ 1.15 fifteen 0 fifty thirty twenty 5 1.25

16 35 fifty fifteen 0 5½ 1.15 17 35 55 10 0 6 1.20 eighteen 40 55 5 0 5½ 1.20 19 thirty twenty 25 25 7 1.15 twenty twenty 45 thirty 5 6 1.20 21 10 60 twenty 10 5 1.25

Claims (6)

1. The mixture for producing metallurgical coke containing fatty or gas-fatty and low-coking coke coals, characterized in that the coals are introduced in the following ratio of components, wt.%:
Fatty or gas-fatty coals 25-65 Low coking coals 35-75 2. The mixture for producing metallurgical coke containing fatty or gas-fatty coals, characterized in that it additionally contains coke lean coals in the following ratio of components, wt.%:
Fatty or gas-fatty coals 25-65 Coke lean coals 35-75,
with the exception of the following ratios of components, wt.%:
Fatty or gas-fatty coals 40 Coke lean coals 60 Fatty or gas-fatty coals fifty Coke lean coals fifty Fat Coals 60 Coke lean coals 40 3. The mixture for producing metallurgical coke containing fatty and coke low-caking coals, characterized in that it additionally contains coke lean coals in the following ratio of components, wt.%:
Fat Coals 25-40 Low coking coals 35-60 Coke lean coals 5-35 4. The mixture for producing metallurgical coke containing gas-fatty and low-coking coke coals, characterized in that it additionally contains coke lean coals in the following ratio of components, wt.%:
Gas Fat Coals 30-55 Low coking coals 30-60 Coke lean coals 5-20 5. The mixture for producing metallurgical coke containing fatty, gas-fatty and low-coking coke coals, characterized in that the coals are introduced in the following ratio of components, wt.%:
Fat Coals 35-40 Gas Fat Coals 5-15 Low coking coals 50-55 6. The mixture for producing metallurgical coke containing fatty, gas-fatty and low coking coking coals, characterized in that it additionally contains coke lean coals in the following ratio of components, wt.%:
Fat Coals 10-30 Gas Fat Coals 20-30 Low coking coals 20-60 Coke lean coals 5-25