Blended coal, coke and preparation method using Indonesian coking coal with a>20% shrinkage

Abstract

This invention discloses a blended coal, coke, and preparation method using Indonesian coking coal with an a content greater than 20% that only shrinks. The blended coal and coke are prepared from the following components by mass percentage: 4%–10% gas coal, 15%–20% gas-rich fat coal, 0%–7% 1 / 3 coking coal, and 1% fat coal. # 8%–12%, coking coal 2 # 5%–10%, coking coal 1 # 5%–10%, coking coal 2 # 8%–12%, coking coal 3 # The composition of the coking coal is as follows: 13%–16% Indonesian coking coal, 5%–15% Indonesian coking coal, and 8%–16% lean coal; the maximum shrinkage a of the Indonesian coking coal is greater than 20%, and the expansion test shows only shrinkage. This invention subdivides coking coal and fat coal from different mines, optimizing coal blending based on the differences in the expansion properties of coking coal, combined with the maximum expansion b of the blended coal, the mineral catalytic index MCI, the caking index G, the maximum thickness of the plastic layer Y, as well as ash, sulfur, and volatile matter content. It uses more low-priced Indonesian coking coal and less high-priced coking coal and fat coal. The proportion of Indonesian coking coal with only shrinkage and a > 20% can reach 15%, offering the advantage of low cost. Its coke has excellent crush resistance, abrasion resistance, and post-reaction strength, meeting the requirements of 2500m. 3 The above are the requirements for stable production of blast furnaces.

Description

Technical Field

[0001] This invention relates to the field of coal blending and coking technology, specifically to a blended coal, coke, and preparation method of Indonesian coking coal with a > 20% shrinkage. Background Technology

[0002] In my country's coking coal resources, low-rank, high-volatile gas coal and 1 / 3 coking coal account for 45.73%, coking coal accounts for 23.61%, lean coal (including semi-lean coal) accounts for 15.89%, and fat coal (including gas-fat coal) accounts for 12.81%. In recent years, the exploitable quantity of high-quality coking coal (mainly coking coal and fat coal) in my country has been shrinking, prices have been rising continuously, and coal blending has occurred frequently. To expand coking coal procurement channels and reduce blending costs, domestic coking enterprises have been continuously increasing the proportion of imported coking coal in their blends. Due to the different coal-forming environments of coking coal in different regions, although the volatile matter and caking properties meet the classification standards for domestic coking coal, their coking characteristics and geological properties have their own unique features, which to some extent restricts the efficient application of imported coking coal resources.

[0003] Currently, there is an Indonesian coking coal on the market with the following characteristics: average maximum reflectance (Rran) of vitrinite (1.25%~1.45%, standard deviation 0.06~0.09%), active content 60%~70%, Gibbs freeness plastic range of 30℃~50℃, flowability (MF) ≤50 ddpm, binding index (G) 80~85, maximum resin layer thickness (Y) 11~13 mm, maximum shrinkage (a) >20%, no expansion (expansion curve type: shrinkage only), mineral catalytic index (MCI) 2.4~2.9%, and no ash-based volatile matter (V) when dry. daf Sulfur content is 20-25%. t,d Ash content A on a dry basis is 0.40~0.60%. d The content is 8.00-8.80%. This coal type belongs to coking coal according to Chinese coal classification and has a low cost. Using this coal in blending for coking can reduce blending costs. However, the results of a 40kg test coke oven show that the coke's mechanical properties are poor and its hot-state properties are average, unlike typical domestic coking coal. In daily production, using this Indonesian coking coal to replace domestic coking coal leads to a decrease in the coke's shatter resistance strength (M). 40 Decrease, wear resistance M 10 The strength CSR decreases after the reaction, and the quality of coke cannot meet the stable production requirements of blast furnaces with a capacity of 2500m³ or more. Summary of the Invention

[0004] To overcome the shortcomings of existing technologies, the present invention aims to provide a blended coal, coke, and preparation method using Indonesian coking coal with a > 20% shrinkage, thereby solving the problem of the shatter resistance M of coke produced using Indonesian coking coal. 40The problem of low CSR (coking strength) after reaction, which fails to meet the quality requirements of high-quality metallurgical coke, necessitates increasing the blending ratio of Indonesian coking coal, expanding the application range of coking coal, reducing blending costs, and ensuring the full and optimized utilization of imported coking coal resources.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A blended coal containing Indonesian coking coal with an a content greater than 20% and exhibiting only shrinkage is obtained by blending the following components by mass percentage: 4-10% gas coal, 15-20% gas-rich fat coal, 0-7% 1 / 3 coking coal, and 1% fat coal. # 8~12%, coking coal 2 # 5~10%, coking coal 1 # 5-10%, coking coal 2 # 8~12%, coking coal 3 # 13-16%, Indonesian coking coal 5-15%, lean coal 8-16%; the maximum shrinkage a of the Indonesian coking coal is greater than 20%, and the expansion test shows only shrinkage.

[0007] Preferably, the Indonesian coking coal has the following quality indicators: vitrinite average maximum reflectance Rran is 1.25~1.45%, standard deviation is 0.06~0.09%, and active component ratio is 60~70%; Kierkegaard fluidity plastic range is 30~50℃, maximum fluidity MF≤50ddpm; caking index G is 80~85; maximum plastic layer thickness Y is 11~13mm; maximum shrinkage a>20%, shrinkage only, no expansion; mineral catalytic index MCI is 2.4~2.9%; and dry ash-free volatile matter V daf Sulfur content is 20-25%. t,d Ash content A on a dry basis is 0.40~0.60%. d The CSR is 8.00~8.80%, and the CSR of coke produced by a 40kg load small coke oven is 55~60%.

[0008] Preferably, the caking index G of the gas coal is ≥83, the maximum shrinkage a is 16~24%, and the maximum expansion b is 10~15%.

[0009] The sulfur content (S) of the gas-rich coal t,d The viscosity is 1.60~2.00%, the adhesion index G≥91, the maximum shrinkage a is 5~10%, and the maximum expansion b is 140~180%;

[0010] The sulfur content (S) of the 1 / 3 coking coal t,d The content of the adhesive index is 0.30~0.50%, the adhesion index G≥90, the maximum shrinkage a is 25~30%, and the maximum expansion b is 90~100%.

[0011] The fat coal 1# sulfur content S t,d The viscosity is 1.70~2.00%, the adhesion index G≥90, the maximum shrinkage a is 25~30%, and the maximum expansion b is 175~185%;

[0012] The coking coal 2 # sulfur content S t,d The content is 0.30~0.45%, the adhesion index G≥90, the maximum shrinkage a is 10~20%, and the maximum expansion b is 105~115%;

[0013] The coking coal 1 # sulfur content S t,d The viscosity is 0.55-0.75%, the adhesion index G is 85-90, the maximum shrinkage a is 20-25%, the maximum expansion b is 101-108%, and the CSR of coke produced in a 40kg load small coke oven is 55-59%.

[0014] The coking coal 2 # sulfur content S t,d The viscosity index (G) is 1.25-1.45%, the caking index (A) is 80-85, the maximum shrinkage (a) is 16-20%, the maximum expansion (b) is 45-55%, and the coke production rate (CSR) of coke produced in a 40kg load small coke oven is 75-80%.

[0015] The coking coal 3 # sulfur content S t,d The viscosity is 1.40-1.80%, the adhesion index G is 85-90, the maximum shrinkage a is 3-9%, the maximum expansion b is 165-185%, and the CSR of coke produced in a 40kg load small coke oven is 68-73%.

[0016] The lean coal has a caking index G≥45, a maximum shrinkage a of 10~15%, and no expansion in the expansion test.

[0017] Preferably, the maximum expansion degree b of the blended coal after blending is 85-95%, the caking index G is 83-85, the maximum thickness Y of the plastic layer is 16-18 mm, the mineral catalytic index MCI is 2.5-2.8%, and the ash content A is... d It is 9.00~9.50%.

[0018] A type of coke is produced from the above-mentioned blended coal containing Indonesian coking coal with a > 20% shrinkage.

[0019] Preferably, the coke has a crush resistance M 40 ≥88%, abrasion resistance M 10 ≤6.0%, post-reaction strength CSR≥68%.

[0020] The above-mentioned method for preparing coke includes the following steps:

[0021] 1) Coal blending should be carried out according to the following composition and weight percentage: gas coal 4-10%, gas-rich coal 15-20%, 1 / 3 coking coal 0-7%, and fat coal 1 # 8~12%, coking coal 2 # 5~10%, coking coal 1 # 5-10%, coking coal 2 # 8~12%, coking coal 3 # 13-16%, Indonesian coking coal 5-15%, lean coal 8-16%;

[0022] 2) Crushing of mixed coal: Crushing the mixed coal after blending in step 1);

[0023] 3) Coking: The crushed mixed coal is fed into a coke oven for coking;

[0024] 4) Use dry quenching method to cool and remove coke.

[0025] Preferably, in step 2), after the mixed coal is crushed, the mixed coal with a particle size of less than 3 mm accounts for 70-75% of its total mass.

[0026] Preferably, in step 3), the coke oven is a 7m top-loading coke oven; the standard temperatures on the machine side and the coke side are 1235±10℃ and 1295±10℃, respectively, and the coking time is 24.5±1h.

[0027] The above-mentioned coke can be used in 2500m 3 The above blast furnace smelting.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0029] This invention provides a blended coal, coke, and preparation method using Indonesian coking coal with a content greater than 20% that only shrinks. It subdivides coking coal and fat coal from different mining sites, optimizes the blending based on the differences in the expansion properties of coking coal, and combines the maximum expansion degree b, mineral catalytic index MCI, caking index G, maximum plastic layer thickness Y, as well as ash, sulfur, and volatile matter content. This method uses more low-priced Indonesian coking coal and less high-priced coking coal and fat coal, thereby reducing the cost of blending.

[0030] This invention develops a blended coal, coke, and preparation method using Indonesian coking coal with an a content greater than 20% that only shrinks. The proportion of Indonesian coking coal with an a content greater than 20% that only shrinks can reach 15%. Coking is carried out in a 7m top-charged coke oven, and the resulting coke is M. 40 ≥88%, M 10 ≤6.0%, CSR≥68%, coke quality meets 2500m 3 The above are the requirements for stable production of blast furnaces. Attached Figure Description

[0031] Figure 1 This is a random reflectance distribution diagram of the vitrinite group of Indonesian coking coal according to the present invention. Detailed Implementation

[0032] To better explain the present invention, the main contents of the present invention are further illustrated below with reference to the accompanying drawings and specific embodiments, but the contents of the present invention are not limited to the following embodiments.

[0033] This invention provides a scheme for blending Indonesian coking coal with a shrinkage rate of >20%. Based on the shrinkage characteristic of Indonesian coking coal, the proportion of coking coal with different expansibility is adjusted within the coking coal group. At the same time, the proportion of high-expansibility gas-rich coal, fat coal, and 1 / 3 coking coal is adjusted by combining factors such as price and catalytic index MCI to ensure the expansibility of the blended coal, thereby enabling different coking coals to be fully integrated during the melting process.

[0034] The specific coal quality indicators of the Indonesian coking coal with shrinkage only (a>20%) are as follows: Vitrin average maximum reflectance Rran 1.25~1.45%, standard deviation 0.06~0.09%; active ingredient ratio 60~70%; Gibbs freeness plastic range 30~50℃; maximum flowability MF ≤50 ddpm; bonding index G 80~85; maximum plastic layer thickness Y 11~13mm; maximum shrinkage a>20%; no expansion; expansion curve type: shrinkage only; mineral catalytic index MCI 2.4~2.9%; dry ash-free volatile matter V. daf Sulfur content is 20-25%. t,d Ash content A on a dry basis is 0.40~0.60%. d The CSR of coke produced in a 40kg load small coke oven is 55-60%, ranging from 8.00% to 8.80%. The specific coal quality indicators mentioned above were measured according to current national standard methods. The histogram of the average random reflectance and distribution of the vitrinite of this Indonesian coking coal is shown below. Figure 1 As shown.

[0035] The preparation method of the blended coal and coke using Indonesian coking coal with a content greater than 20% and shrinkage only includes the following steps:

[0036] 1) Coal blending;

[0037] (1) Coal type classification: coal types are selected and classified for production:

[0038] Coal Fertilizer 1 # Sulfur content (S) t,d : 1.70~2.00%, adhesion index G≥90, maximum shrinkage a: 25~30%; maximum expansion b: 175~185%.

[0039] Coal 2 # Sulfur content (S) t,d0.30~0.45%, adhesion index G≥90, maximum shrinkage a: 10~20%; maximum expansion b: 105~115%.

[0040] Coking coal 1 # Sulfur content (S) t,d 0.55~0.75%, adhesion index G: 85~90, maximum shrinkage a: 20~25%; maximum expansion b: 101~108%, CSR of coke produced by a 40kg load small coke oven: 55~59%.

[0041] Coking coal 2 # Sulfur content (S) t,d 1.25~1.45%, adhesion index G: 80~85, maximum shrinkage a: 16~20%; maximum expansion b: 45~55%, CSR of coke produced by a 40kg load small coke oven: 75~80%.

[0042] Coking coal 3 # Sulfur content (S) t,d : 1.40~1.80%, adhesion index G: 85~90, maximum shrinkage a: 3~9%; maximum expansion b: 165~185%, CSR of coke produced by a 40kg load small coke oven: 68~73%.

[0043] Gas coal: caking index G≥83, maximum shrinkage a: 16~24%, maximum expansion b: 10~15%;

[0044] Gas-rich coal: Sulfur content (S) t,d : 1.60~2.00%, adhesion index G≥91, maximum shrinkage a: 5~10%; maximum expansion b: 140~180%.

[0045] 1 / 3 coking coal: sulfur content (S) t,d : 0.30~0.50%, adhesion index G≥90, maximum shrinkage a: 25~30%; maximum expansion b: 90~100%.

[0046] Lean coal: caking index G≥45, maximum shrinkage a: 10~15%; maximum expansion b: none.

[0047] Price ranking of highly expansive coking coal: Fat Coal 2 # > Coal Fat 1 # >1 / 3 coking coal > gas-rich coal.

[0048] (2) Coal blending: The coal shall be blended according to the following mass percentages: gas coal 4~10%, gas-rich coal 15~20%, 1 / 3 coking coal 0~7%, and fat coal 1 # 8~12%, coking coal 2 # 5~10%, coking coal 1 #5-10%, coking coal 2 # 8~12%, coking coal 3 # 13-16%, Indonesian coking coal 5-15%, lean coal 8-16%.

[0049] In this coal blending scheme, low-priced Indonesian coking coal is used to replace part of the high-priced coking coal, increasing the proportion of highly expansive gas-rich coal and reducing the amount of high-priced fat coal and 1 / 3 of the coking coal. Simultaneously, based on the blending ratio of Indonesian coking coal, the proportion of coking coal is adjusted, and the proportion of low-priced lean coal is increased to ensure that the final blended coal has a maximum expansion (b) of 85-95%, a caking index (G) of 83-85, a maximum plastic layer thickness (Y) of 16-18 mm, a mineral catalytic index (MCI) of 2.5-2.8%, and an ash content (A). d It is 9.00~9.50%.

[0050] 2) Crushing: The mixed coal obtained after blending is fed into a crusher by conveyor belt and crushed. The mixed coal with a particle size of less than 3mm accounts for 70-75% of its total mass.

[0051] 3) Coking: The crushed mixed coal is fed into a 7m top-loading coke oven for coking. The standard temperatures on the machine side and coke side are 1235℃ and 1295℃, respectively, and the coking time is 24.5h.

[0052] 4) Dry quenching is used for coke cooling and discharge. Coke quality is tested, and the coke's crush resistance strength (M) is measured. 40 Abrasion resistance M 10 Indicators such as coke reactivity (CRI) and post-reaction strength (CSR) are used.

[0053] The present invention will be further illustrated below through specific embodiments and comparative examples.

[0054] The specific coal blending ratios for the embodiments and comparative examples are shown in Table 1: Comparative Example 1 uses a coal blending scheme from the prior art, without the use of Indonesian coking coal; Comparative Example 2 uses 5% of the coking coal from Comparative Example 1. # Replace with Indonesian coking coal; Comparison ratio 3: 5% coking coal 1 # 5% coking coal 3 # Replace with Indonesian coking coal; Example 1 uses 10% Indonesian coking coal according to the scheme of the present invention, and Example 2 uses 15% Indonesian coking coal according to the scheme of the present invention.

[0055] All the above embodiments and comparative examples involved crushing, coking, and coking of coal after blending using the methods described above. The crushing strength M of the product coke was measured. 40 Abrasion resistance M 10 The coke reaction strength (CSR) was measured, and the results are shown in Table 1.

[0056] Table 1: Coking coal blending (mass percentage) and coke quality data of the embodiments and comparative examples of the present invention

[0057]

[0058] As can be seen from the five schemes in Table 1, Comparative Examples 2 and 3 simply replace domestic coking coal with Indonesian coking coal in the same proportion as the existing technology in Comparative Example 1, resulting in a decrease in the coke's shatter resistance M. 40 Reduce M after blending with Indonesian coking coal by 10% 40 The proportion of Indonesian coking coal was reduced to below 88%. This indicates that Indonesian coking coal cannot be simply replaced by traditional coal blending methods during the coking process; its characteristic of shrinking but not expanding during coking must be taken into account. Therefore, Examples 1 and 2 adopted the Indonesian coking coal substitution scheme of the present invention. Based on the maximum expansion degree b, mineral catalytic index MCI, caking index G, and maximum plastic layer thickness Y of the blended coal, as well as ash, sulfur, and volatile matter content, the coal blending was optimized to reduce the proportion of high-priced coking coal and fat coal, and increase the proportion of low-priced Indonesian coking coal, gas-rich coal, and lean coal. This achieved the goal of reducing coal blending costs and stabilizing coke quality, and the obtained coke had a crushing strength M. 40 The wear resistance is 88-89%, and the wear resistance M is... 10 The coke post-reaction strength (CSR) is 68-70%, meeting the requirements of 2500m. 3 The above are the requirements for stable production of blast furnaces.

[0059] The above description is only a specific example of the present invention. It should be noted that the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made using the technical concept and technical solution of the present invention, or the direct application of the technical concept and technical solution of the present invention to other occasions without modification, are all within the protection scope of the present invention.

[0060] All other unspecified parts belong to the prior art.

Claims

1. A blended coal containing Indonesian coking coal with a > 20% shrinkage, characterized in that: It is obtained by blending the following components by mass percentage: 4-10% gas coal, 15-20% gas-rich coal, 0-7% 1 / 3 coking coal, and 1% fat coal. # 8~12%, coking coal 2 # 5~10%, coking coal 1 # 5-10%, coking coal 2 # 8~12%, coking coal 3 # 13-16%, Indonesian coking coal 5-15%, lean coal 8-16%; the maximum shrinkage a of the Indonesian coking coal is greater than 20%, and the expansion test shows only shrinkage; The quality indicators of the Indonesian coking coal are as follows: vitrinite average maximum reflectance Rran is 1.25~1.45%, standard deviation is 0.06~0.09%, and active component ratio is 60~70%; Kierkegaard fluidity plastic range is 30~50℃, maximum fluidity MF≤50ddpm; caking index G is 80~85; maximum plastic layer thickness Y is 11~13mm; maximum shrinkage a>20%, no expansion, only shrinkage; mineral catalytic index MCI is 2.4~2.9%; dry ash-free volatile matter V daf Sulfur content is 20-25%. t,d Ash content A on a dry basis is 0.40~0.60%. d The CSR (Coke Refining Rate) is 8.00-8.80% for coke produced in a 40kg load small coke oven, and 55-60% for coke. The blended coal has a maximum expansion degree (b) of 85-95%, a caking index (G) of 83-85, a maximum plastic layer thickness (Y) of 16-18 mm, a mineral catalytic index (MCI) of 2.5-2.8%, and an ash content (A). d It is 9.00~9.50%.

2. The blended coal according to claim 1, comprising Indonesian coking coal with a > 20% shrinkage, is characterized in that: The caking index G of the gas coal is ≥83, the maximum shrinkage a is 16~24%, and the maximum expansion b is 10~15%. The sulfur content (S) of the gas-rich coal t,d The viscosity is 1.60~2.00%, the adhesion index G≥91, the maximum shrinkage a is 5~10%, and the maximum expansion b is 140~180%; The sulfur content (S) of the 1 / 3 coking coal t,d The content of the adhesive index is 0.30~0.50%, the adhesion index G≥90, the maximum shrinkage a is 25~30%, and the maximum expansion b is 90~100%. The fat coal 1 # sulfur content S t,d The viscosity is 1.70~2.00%, the adhesion index G≥90, the maximum shrinkage a is 25~30%, and the maximum expansion b is 175~185%; The coking coal 2 # sulfur content S t,d The content is 0.30~0.45%, the adhesion index G≥90, the maximum shrinkage a is 10~20%, and the maximum expansion b is 105~115%; The coking coal 1 # sulfur content S t,d The viscosity is 0.55-0.75%, the adhesion index G is 85-90, the maximum shrinkage a is 20-25%, the maximum expansion b is 101-108%, and the CSR of coke produced in a 40kg load small coke oven is 55-59%. The coking coal 2 # sulfur content S t,d The viscosity index (G) is 1.25-1.45%, the caking index (A) is 80-85, the maximum shrinkage (a) is 16-20%, the maximum expansion (b) is 45-55%, and the coke production rate (CSR) of coke produced in a 40kg load small coke oven is 75-80%. The coking coal 3 # sulfur content S t,d The viscosity is 1.40-1.80%, the adhesion index G is 85-90, the maximum shrinkage a is 3-9%, the maximum expansion b is 165-185%, and the CSR of coke produced in a 40kg load small coke oven is 68-73%. The lean coal has a caking index G≥45, a maximum shrinkage a of 10~15%, and no expansion in the expansion test.

3. A type of coke, characterized in that: It is prepared from the blended coal of any one of claims 1 to 2, which contains Indonesian coking coal with a > 20% shrinkage.

4. The coke according to claim 3, characterized in that: The crush resistance M of the coke 40 ≥88%, abrasion resistance M 10 ≤6.0%, post-reaction strength CSR≥68%.

5. The method for preparing coke according to claim 3 or 4, characterized in that: Includes the following steps: 1) Coal blending should be carried out according to the following composition and weight percentage: gas coal 4-10%, gas-rich coal 15-20%, 1 / 3 coking coal 0-7%, and fat coal 1 # 8~12%, coking coal 2 # 5~10%, coking coal 1 # 5-10%, coking coal 2 # 8~12%, coking coal 3 # 13-16%, Indonesian coking coal 5-15%, lean coal 8-16%; 2) Crushing of mixed coal: Crushing the mixed coal after blending in step 1); 3) Coking: The crushed mixed coal is fed into a coke oven for coking; 4) Use dry quenching method to cool and remove coke.

6. The preparation method according to claim 5, characterized in that: In step 2), after the mixed coal is crushed, the mixed coal with a particle size of less than 3 mm accounts for 70-75% of its total mass.

7. The preparation method according to claim 5, characterized in that: In step 3), the coke oven is a 7m top-loading coke oven; the standard temperatures on the machine side and coke side are 1235±10℃ and 1295±10℃, respectively, and the coking time is 24.5±1h.

8. The application of the coke according to claim 3 or 4, characterized in that: For 2500m 3 The above blast furnace smelting.

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