RU2461602C1 - Method for charge forming for furnace coke obtaining - Google Patents

Abstract

FIELD: oil and gas production.

SUBSTANCE: mine-groups are composed depending upon vitrinite reflectance (Ro, %), volatile matter content (V^daf, %) and thickness of formation layer (U, mm). Mine-groups are formed with the following characteristics: gas coal mine-group (GCG): Ro<0.85%, V^daf>34, %, U≥12 mm; fat coal mine-group (FCG): Ro=0.85-1.05%, V^daf=30.0-34.0%, U≥14 mm; coaking coal mine-group (CCG): Ro=1.06-1.30%, V^daf=20.0-29.9%, U≥10 mm; coaking low-caking coal mine-group (CLCCG): Ro=1.06-1.30%, V^daf =20.0-29.9%, U≥10 mm; lean caking coal mine-group (LCCG): Ro>1.30%, V^daf<20.0%, U≥8 mm; mine-group - relatively suitable raw material for coking (RSRM) is formed from coke and by-product process wastes and/or coals relatively suitable for coking. The charge optimal composition is determined based on expected quality characteristics of coke. The charge is composed from mine-groups with the following component ratio, wt %: GCG - 0-40, FCG - 30-70, CCG - 0-20, CLCCG - 0-30, LCCG - 0-30, RSRM - 0-6.

EFFECT: invention allows selecting the best ratio of coals supplied to coking and optimising the charge by technological and economical indices with obtaining maximum possible quality of coke for blast-furnace process, settling the tasks of utilisation of hazardous wastes of coke and by-product process, increase of coke blast-furnace efficiency and reduction of coke net price.

3 cl, 1 dwg, 3 tbl

Description

The invention relates to by-product coke production, in particular to a method for forming a coal charge for coking.

With the transition to market management methods, the existing raw material coal base of the plants was destroyed, and for this period it is characterized by significant instability of both the brand composition of the supplied coal and concentrates, and the variability of their quality indicators. At the same time, the deficit of the most valuable coking coal grades Zh, K, KO, OS. In these conditions, the issues of operational and rational blending are of particular relevance.

Various attempts have been made to make up for the main groups that are missing in the mixture by introducing specially prepared sintering, coking or exhausting additives.

A known method of forming a mixture for the production of metallurgical coke from technological coals, such as fatty, gaseous fatty, low-coking coke, sintering refined, in which sapromixitic coal is used as a sintering additive, in which the ash and pyrite sulfur content is first reduced, then ultrafine grinding is performed to particles with a size of 5-50 microns and evenly mixed with other components, adding a certain amount of coals of energy grades (RF patent No. 2312883, class C10B 57/04, publ. 20.12.2007).

A mixture is also known for producing metallurgical coke (RF patent No. 2224782, class СВВ 57/04, publ. 02.27.2004), containing fatty, lean-sintering coals and a sintering additive, which additionally contains gas-fat, coke low-sintering coals, and a sintering additive obtained by mixing a pitch-like product with plastic waste in a ratio of 1: 0.1-0.2, heating the mixture to 300-350 ° C for 0.5-1.0 hours in the following ratio of components, wt.%:

Gas fat coals 15-20 Fat Coals 20-30 Low coking coals 20-40 Sintering additive 3-6 Sintered coals rest

A significant drawback of these charges is the increase in the cost of coke and the need for special technological measures in the process of preparing the charge for coking.

There is a method of determining the optimal composition of a coal charge, consisting of sintering, exhaust, coke components, using the calculation of the optimality coefficient (RF patent No. 2355730, CL SV 57/04, publ. 05.20.2007).

The main disadvantages of this method is the inability to attribute specific suppliers to one of the components of the coal charge, if the incoming coal concentrate includes coals belonging to different technological brands.

As a prototype, a mixture was selected for the production of metallurgical coke (RF patent No. 2334779, class СВВ 57/04, publ. 09/27/2008) containing gas-fat, fatty, coke sintering, lean-sintering coals, the composition of which additionally contains coke lean coals in the following ratio of components, wt.%:

Fat Coals 12-48 Sintered coals 11-57 Gas fat coals 2-34 Coke baking 1-30 Coke lean coals 1-17

Currently, a significant part of the components of the coal charge is represented by concentrates of concentration plants. Concentrates, as a rule, are a mixture of several grades of coal and cannot be assigned to a specific mine group using GOST 25543. Also, due to the current situation on the coal market, it is often not possible to provide coking enterprises with all declared coal grades. Therefore, a significant disadvantage of this mixture for producing metallurgical coke are:

- the inability to attribute incoming concentrates to the mine group only on the basis of classification GOST;

- lack of quality indicators for referring to a particular mine group;

- the lack of a formulated criterion for comparing and choosing the optimal mixture;

- there are no options for introducing into the charge the waste of KHP and conditionally coking coal to reduce costs and eliminate environmental pollution.

The objective of the invention is to develop a method that allows you to choose the optimal ratio of incoming coal concentrates (use any set) to obtain the highest possible quality of coke for blast furnace production. At the same time, the peculiarities and needs of the coke production technology are taken into account, the possibility of utilizing coke production waste, reducing the cost of the charge due to coals conventionally suitable for coking, increasing the productivity of coke ovens and reducing the cost of coke is provided for.

The problem is solved by the fact that coal and coal concentrates coming into coking make up mine groups depending on the reflection index of vitrinite (Ro,%), the yield of volatiles (V ^daf ,%) and the thickness of the plastic layer (Y, mm), which have the following characteristics:

coal gas mine group (GGU): Ro <0.85%, V ^daf > 34,%, Y≥12 mm;

mine group of fatty coals (GLC): Ro = 0.85-1.05%, V ^daf = 30.0-34.0%, Y≥14 mm;

coke coal mine group (GKU): Ro = 1.06-1.30%, V ^daf = 20.0-29.9%, Y≥10 mm;

mine group of coke low-caking coals (GCSU): Ro = 1.06-1.30%, V ^daf = 20.0-29.9%, Y≥10 mm;

mine group of lean sintering coals (GOSU): Ro> 1.30%, V ^daf <20.0%, Y≥8 mm;

the mine group conditionally suitable raw materials for coking (OPS) is formed from waste from coke production and / or coals conventionally suitable for coking, the optimal composition of the charge is determined from the calculation of the expected quality characteristics of coke (Ad,% - ash, Sd,% - cepa, coke strength - M40,%; M10,%), while the mixture is made up of mine groups in the following ratio of components, wt.%:

GSU - coal gas mine group 0-50% ГЖУ - coal group 30-70% GKU - coke coal mine group 0-50% GKSU - mine group coke low-sintering coals 0-30% GOSU - coal-sintering coal mine group 0-50% additive UPS - mine group conventionally suitable raw materials for coking 0-6%

When forming a mine group (UPS):

- from coke-chemical production wastes, which are fuses, coke dust, coke sludge, their amount in the charge for coking does not exceed 1%;

- from coals conventionally suitable for coking, coals containing more than 50% of grades according to GOST 25543 are used: coke low-sintering low-metamorphosed (KOS), lean (T), lean sintering (TS), gas (G), while their amount in the charge for coking does not exceed 5%.

The essence of the proposed technical solution.

To obtain the highest possible quality of coke from incoming coal concentrates, a method for forming the optimal composition of the mixture, consisting of three stages, is proposed.

The first stage of the optimization of the charge consists of the distribution of coal among the mine groups, based on the quality indicators of the incoming coal raw materials (assessment of the incoming coal raw materials from the point of view of coking ability and the charge structure). The main indicator for the separation of coal into mine groups is the vitrinite reflection index (Ro,%). The optical properties of coals are widely used to characterize coals and establish the stage of metamorphism, since there is a relationship between the reflection index of vitrinite and the carbon content, the yield of volatiles and other parameters of the composition and structure of coal (Agushevich I.V. Bronovets T.M. et al. Standard Coal Testing Methods. Coal Classification. - M.: NTK Terek, 2008. - 368 p., p.241-242). Auxiliary characteristics for determining the mine group: the yield of volatile substances (V ^daf ,%), the thickness of the plastic layer (Y, mm).

For the separation of coal into mine groups, the following characteristics are defined:

coal gas mine group (GGU): Ro <0.85%, V ^daf > 34,%, Y≥12 mm;

mine group of fatty coals (GLC): Ro = 0.85-1.05%, V ^daf = 30.0-34.0%, Y≥14 mm;

coke coal mine group (GKU): Ro = 1.06-1.30%, V ^daf = 20.0-29.9%, Y≥10 mm;

mine group of coke low-caking coals (GCSU): Ro = 1.06-1.30%, V ^daf = 20.0-29.9%, Y≥10 mm;

mine group of lean sintering coals (GOSU): Ro> 1.30%, V ^daf <20.0%, Y≥8 mm;

the mine group conditionally suitable raw materials for coking (OPS) is formed from coke-chemical production wastes (fus, coke dust, coke sludge) - not more than 1% in the charge for coking and / or coals conventionally suitable for coking (containing more than 50% of KSN, T grades , TS, G according to GOST 25543) - not more than 5% in the charge for coking.

The characteristics of the mine groups are established based on the requirements for each mine group and its role in the coking process. Also, the unification of suppliers with similar quality characteristics into mine groups makes it possible to increase the uniformity in quality indicators of the charge for coking.

At the second stage of optimization of the charge, variants of the percentage ratio of the mine groups are compiled that fall within the limits set for each mine group, taking into account:

- actual deliveries;

- the possibility of utilizing wastes of coke and chemical production and reducing the cost of the charge due to coals conventionally suitable for coking;

- exclusion of options that do not meet the coking technology (decrease in coke yield, increase in amperage);

- the ratio of the optimal ratio (the ability of gas-fat and fatty coals of different deposits to take a different amount of exhaust coals).

For the compiled variants of the charge, the predicted qualitative characteristics of coke are calculated.

The calculation is analogous to a mathematical model based on the chemical and petragraphic parameters of a coal charge taking into account the coking period and coke quenching technology (Stankevich A.S. et al. Rational distribution of coals and optimization of the charge composition for coking. Coke and Chemistry. 2003. No. 9, p. .8-16.)

At the third stage, from the calculated qualitative characteristics of coke, the optimal composition of the charge composition for coking is determined taking into account the technological and economic indicators of the coke production and the requirements of the blast furnace process and the charge is composed of mine groups in the following ratio of components, wt.%:

GSU - coal gas mine group 0-50% ГЖУ - coal group 30-70% GKU - coke coal mine group 0-50% GKSU - mine group coke low-sintering coals 0-30% GOSU - coal-sintering coal mine group 0-50% additive UPS mine group conventionally suitable raw materials for coking 0-6%

The declared limits are selected experimentally.

The GZhU mine group is the main component that constitutes the charge for coking. The content of the mine group GZhU less than 30% reduces the strength characteristics of coke. With an increase of more than 70%, the resulting mixture is refined, which not only leads to a decrease in the strength of coke, but also affects the technical and operational parameters of coke oven batteries.

The GSU mine group is introduced into the charge as an addition or partial replacement of GZhU coals in order to reduce the cost of the charge. With an increase in this mine group by more than 50%, the coke strength indicator M10 sharply decreases.

The GKU mine group is coke-forming and includes valuable coal. An increase of more than 50% is unreasonable, since with a slight improvement in the strength characteristics of the resulting coke, its cost increases significantly.

Mine groups GKSU, GOSU relate to the sintering portion of the charge for coking and are both interchangeable and complementary to each other mine groups. The limits on the upper limit are selected experimentally based on the technological capabilities of coke oven batteries, which: minimizes the occurrence of increased amperage, drilling of coke ovens, destruction of masonry, increases the life of coke oven batteries.

The UPS mine group is introduced into the charge as an additive with the aim of the possibility of utilizing wastes of coke and chemical production and reducing the cost of the charge.

When forming a mine group (UPS):

- from coke-chemical production wastes, which are fuses, coke dust, coke sludge, their amount in the charge for coking does not exceed 1%;

- from coals conventionally suitable for coking, coals containing more than 50% of grades according to GOST 25543 are used: coke low-sintering low-metamorphosed (KOS), lean (T), lean sintering (TS), gas (G), while their amount in the charge for coking does not exceed 5%.

Examples of the method.

1. Purpose: Determination of the maximum possible participation of coals of “TsOF Pechora GZhO” coals in the coking charge without significant deterioration of the strength characteristics of coke.

Table 1 Coking charge options mine group The composition of the charge,% Base one 2 3 four 5 6 7 GSU TsOF Pechora 9 eighteen twenty 23 26 29th 32,0 35.0 GZHU TsOF Pechora 65 56 47 44 41 38 35.0 32,0 GKU TsOF Pechora 8 8 8 8 8 8 8.0 8.0 GOSU TsOF Siberia eighteen eighteen 25 25 25 25 25.0 25.0 Total one hundred one hundred one hundred one hundred one hundred one hundred one hundred one hundred Estimated indicators of the finished mixture Ad% 8.9 8.9 8.9 8.9 8.9 8.9 8.9 8.9 Vd,% 25.8 26.8 26.0 26.1 26.1 26,4 26.5 27.0 Mm 14.6 15,2 14.3 14.1 13.9 13.7 13.5 13.3 Ro,% 1,075 1,047 1,066 1,060 1,054 1,049 1,043 1,037 Sd,% 0.67 0.72 0.72 0.74 0.77 0.79 0.82 0.84 Estimated Coke 3-4 batteries Ad% 11,4 11,4 11,4 11,4 11,4 11,4 11,4 11,4 Sd,% 0.56 0.59 0.59 0.62 0.64 0.66 0.68 0.70 M40,% 80.0 79.1 79.8 79.6 79.5 79,4 79.2 79.1 M10,% 7.9 8.7 8.1 8.2 8.3 8.5 8.6 8.7 5-6 batteries Ad% 11,4 11,4 11,4 11,4 11,4 11,4 11,4 11,4 Sd,% 0.56 0.59 0.59 0.62 0.64 0.66 0.68 0.70 M40,% 75,4 74,4 75,2 75.1 75.0 74.9 74.8 74.7 M10,% 7.9 8.6 8.1 8.3 8.4 8.5 8.6 8.8 7-10 batteries Ad% 11,4 11,4 11,4 11,4 11,4 11,4 11,4 11,4 Sd,% 0.56 0.58 0.59 0.62 0.64 0.66 0.68 0.70 M40,% 80,4 80.3 80.2 80.1 80.0 79.8 79.7 79.5 M10,% 7.9 8.0 8.1 8.2 8.3 8.4 8.6 8.7

According to the calculations, option 3 was selected, which provides the specified quality of coke while reducing its cost. Option 4 with a decrease in the quality of coke requires industrial verification.

2. Purpose: Reducing the cost of the charge due to the maximum possible participation of coals “ОF Anzherskaya KSN” in the charge for coking without significant deterioration of the strength characteristics of coke.

table 2 Coking charge options mine group The composition of the charge% Base one 2 3 four GSU TsOF Pechora 16 16 16 16 16 GZHU TsOF Pechora 49 49 49 51 49 GKU TsOF Pechora 5 5 5 5 5 PF Bachaty eleven 8 5 7 eleven GOSU TsOF Siberia 19 19 19 fifteen 13 Oops PF Anzherskaya 3 6 6 6 Total one hundred one hundred one hundred one hundred one hundred Estimated indicators of the finished mixture Ad% 8.7 8.8 8.9 8.8 8.7 Vd,% 26.3 26.3 26.2 26.3 26,4 Mm 14.2 14.1 14.0 14.1 14.1 Ro,% 1,061 1,061 1,061 1,056 1,050 Sd,% 0.67 0.68 0.68 0.68 0.68 Estimated Coke 3-4 batteries Ad% 11.3 11,4 11.5 11,4 11.3 Sd,% 0.55 0.55 0.55 0.56 0.56 M40,% 77.3 77.3 77,2 77.1 77.1 M10,% 7.7 7.8 7.9 7.9 8.0 5-6 batteries Ad% 11.3 11,4 11.5 11,4 11.3 Sd,% 0.55 0.55 0.55 0.56 0.56 M40,% 77.3 77.3 77,2 77,2 77.1 M10,% 7.6 7.7 7.8 7.8 7.9 7-10 batteries Ad% 11,2 11.3 11.5 11,4 11.3 Sd,% 0.56 0.56 0.56 0.56 0.56 M40,% 82.0 81.9 81.8 81.8 81.7 M10,% 7.3 7.3 7.4 7.5 7.5

According to the calculations, option 3 was selected, which provides a decrease in the cost of coke by 9.6% with a slight decrease in quality.

Systematic work on the selection of a charge for coking using this method has been carried out since November 2008, as a result, there was a significant improvement in the quality of CherMK coke. As can be seen from table No. 3, the strength characteristics of coke improved in all three blocks of coke oven batteries.

Table 3 2008 year Coke shop №1 Coke shop №2 KB №№ 3-4 KB No. 5-6 KB No. 8-10 M40,% M10,% M40,% M10,% M40,% M10,% January 75.1 8.4 72.3 7.7 79.0 7.9 February 73.5 8.6 73,2 7.8 78.9 7.8 March 78.8 8.1 74,4 7.9 78.9 7.8 April 76.5 8.5 75.0 7.8 79.1 7.8 May 77.6 8.1 74.6 7.6 79.1 7.7 June 76,4 8.2 74.0 7.7 78.9 7.8 July 75.8 8.5 73.3 8.1 79.3 7.8 August 78.3 8.3 71.1 8.1 79.1 7.8 September 76.8 8.4 71.6 8.2 79.2 7.8 October 79.5 8.1 73.8 7.8 79,4 7.8 Average 76.8 8.3 73.3 7.9 79.1 7.8 November 80.2 8.1 78.7 7.1 81.4 7.7 December 81.4 8.1 78.7 7.1 79,4 7.7 January 80.1 8.0 75.3 7.6 80,4 7.7 February 80.8 8.0 74.3 7.9 80.2 7.7 March 80.6 7.9 74.8 7.9 81.2 7.6 April 80.0 7.9 76.5 7.8 81.9 7.5 May 81.3 7.8 78.5 7.6 82.5 7.3 June 79,4 8.2 78.3 8.0 82.3 7.4 July 80.3 8.1 80 7.9 82.5 7.3 August 81.7 7.7 79.1 7.8 83.1 7.2 September 81.2 7.7 78.8 7.9 83.1 7.2 Average 80.6 7.9 77.6 7.6 81.6 7.4 The difference in strength characteristics of coke before and after implementation +3.8 -0.4 +4.3 -0.3 +2.5 -0.4

In accordance with the drawings, a close correlation was established between the actual and calculated indicators of coke strength.

The technical and economic advantages of the proposed method consist in the fact that its implementation allowed to increase the productivity of coke ovens by 0.3-0.5%, while the mechanical strength of coke was increased with an increase in M40 by 2.5-4.3% and a decrease M10 indicator by 0.3-0.4%, the cost of coke was reduced by 3.2%.

Thus, the claimed method of compiling the charge allows you to choose the best ratio of coal coming into coking and optimize the charge both in terms of technological and economic indicators to obtain the highest possible quality of coke for blast furnace production, solve the problems of utilizing harmful wastes of coke production, increase the productivity of coke ovens reduce the cost of coke.

Claims (3)

1. A method of forming a charge for producing metallurgical coke, including the use of groups of coals of gas, fatty, coke, coke, low caking, lean sintering and conditionally suitable, characterized in that the coal groups comprise mine groups depending on the reflection index of vitrinite (Ro,%) the yield of volatiles (V ^daf ,%) and the thickness of the plastic layer (Y, mm), which have the following characteristics:
coal gas mine group (GGU): Ro <0.85%, V ^daf > 34,%, Y≥12 mm;
mine group of fatty coals (GLC): Ro = 0.85-1.05%, V ^daf = 30.0-34.0%, Y≥14 mm;
coke coal mine group (GKU): Ro = 1.06-1.30%, V ^daf = 20.0-29.9%, Y≥10 mm;
mine group of coke low-caking coals (GCSU): Ro = l, 06-l, 30%, V ^daf = 20.0-29.9%, Y <10 mm;
mine group of low-sintering coals (GOSU): Ro> 1.30%, V ^daf <20.0%, Y≥8 mm;
the mine group conditionally suitable raw materials for coking (OPS) is formed from the waste of coke production and / or coals conventionally suitable for coking, the optimal composition of the charge is determined from the calculation of the expected quality characteristics of coke (Ad,% - ash, Sd,% - sulfur, coke strength - M40,%; M10,%), while the mixture is composed of mine groups in the following ratio of components, wt.%:
GSU - coal gas mine group 0-50 ГЖУ - coal group 30-70 GKU - coke coal mine group 0-50 GKSU - mine group coke low-sintering coals 0-30 GOSU - coal sintering coal mine group 0-50 additive UPS - mine group conventionally suitable raw materials for coking 0-6 2. The method according to claim 1, characterized in that when forming a mine group (UPS) from the waste of coke production, which are fuses, coke dust, coke sludge, their amount in the charge for coking does not exceed 1%. 3. The method according to claim 1, characterized in that as a coal mine group (UPS) when forming from coals conventionally suitable for coking, use coals containing more than 50% of grades according to GOST 25543: low-sintering coke low-sintering (KOS), lean (T ), lean sintering (TS), gas (G), while their amount in the charge for coking does not exceed 5%.

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