Method for refining high-quality metallurgical coke by treating residual coking coal resources in Xinjiang 2130 coal mine fire area

Abstract

The invention belongs to the technical field of coking, and particularly discloses a method for refining high-quality metallurgical coke by utilizing a Xinjiang 2130 coal mine fire area governing residual coking coal resource, which comprises the following steps: firstly, preparing residual coking coal, gas coal, 1 # coking coal, 2 # coking coal and 1 / 3 coking coal obtained after fire area governing of the Xinjiang 2130 coal mine area, and washing and processing the fire area governing residual coking coal; then the raw coal is mixed according to the proportion and then crushed, then the crushed mixed coal material is loaded into a carbonization chamber through a coal charging car and heated, and the coal material is softened, fused and solidified into coke; finally, the red coke is pushed out through a coke pusher and then fed into a coke quenching tower to be cooled. Aiming at the problem that the price of the current high-quality coking coal is high, the metallurgical coke is refined by utilizing the residual coking coal obtained after fire area treatment of the Xinjiang 2130 coal mine area, so that the metallurgical coke refining cost is reduced, and the problem that the production cost is high due to the fact that traditional metallurgical coke refining depends on the high-quality coking coal with high price is solved.

Description

Technical Field

[0001] This invention relates to the field of coking technology, specifically to a method for producing high-quality metallurgical coke from residual coking coal resources from the fire zone of Xinjiang 2130 Coal Mine. Background Technology

[0002] High-quality metallurgical coke plays a crucial role in industries such as steel. In steelmaking, it serves as both a primary fuel, providing a continuous and stable high-temperature environment for the blast furnace ironmaking process, allowing iron ore to fully melt and be reduced; and an indispensable reducing agent, reacting with oxygen in the iron ore at high temperatures to reduce iron from the ore and directly participate in the steelmaking process. From a smelting perspective, the high strength of high-quality metallurgical coke allows it to withstand immense pressure and material impact within the blast furnace without easily breaking, thus maintaining good permeability and ensuring uniform airflow distribution within the furnace. This ensures complete fuel combustion and provides sufficient heat for iron ore reduction, improving ironmaking efficiency, shortening smelting time, reducing energy consumption, and lowering production costs. Furthermore, its high wear resistance allows it to maintain a larger particle size during movement and interaction within the furnace, reducing the generation of fine powder and contributing to uniform airflow distribution within the furnace, further ensuring the smooth operation of the smelting process.

[0003] Currently, traditional metallurgical coking methods mainly rely on high-quality coking coal. However, the distribution of high-quality coking coal resources is extremely uneven globally, and reserves are limited. With long-term mining, the problem of resource shortage has become increasingly prominent. Although my country has a certain amount of high-quality coking coal, it is mainly concentrated in a few regions such as Shanxi and Inner Mongolia. Other regions are resource-poor, which leads to a significant increase in cross-regional transportation costs, further pushing up the price of high-quality coking coal.

[0004] Although the open flames of the Xinjiang 2130 coal mine fire zone have been extinguished and the temperature reduced below the critical value after years of fire zone management, a large amount of residual coking coal resources have been formed. These resources are not waste coal in the traditional sense, but rather semi-coking coal that has undergone localized high-temperature pyrolysis within the fire zone. This residual coking coal has advantages such as good caking properties (G > 80) and extremely low sulfur content (St, d < 0.4%). During the coking process, it can also significantly reduce SO2 and NO emissions. X The emissions of pollutants such as smoke and dust are significant, and if not utilized, these residual coking coals will continue to be buried or disposed of along with waste from fire remediation, resulting in a huge waste of resources. Using these residual coking coals to produce high-quality metallurgical coke would not only maximize the utilization of waste resources but also reduce the production cost of high-quality metallurgical coke, while also helping to improve local air quality.

[0005] Therefore, it is necessary to design a method for refining high-quality metallurgical coke by utilizing residual coking coal resources of Xinjiang 2130 coal mine fire area management, so as to solve the problem that traditional metallurgical coke refining relies on high-quality coking coal with high price, resulting in high production cost. SUMMARY

[0006] The purpose of the present application is to provide a method for refining high-quality metallurgical coke by utilizing residual coking coal resources of Xinjiang 2130 coal mine fire area management, so as to solve the problem that traditional metallurgical coke refining relies on high-quality coking coal with high price, resulting in high production cost.

[0007] To achieve the above-mentioned purpose, the basic scheme provided by the present application is as follows: a method for refining high-quality metallurgical coke by utilizing residual coking coal resources of Xinjiang 2130 coal mine fire area management, comprising the following steps: S1: raw material preparation and pretreatment: first, prepare residual coking coal obtained after Xinjiang 2130 coal mine area fire area management, gas coal, 1# coking coal, 2# coking coal and 1 / 3 coking coal, then wash and process the fire area management residual coking coal, so that the ash content Ad of the fire area management residual coking coal is ≤10.5%, the total sulfur St,d is ≤0.4%, the dry ash-free base volatile matter Vdaf is 20.0%-25.0%, and the caking index G is ≥80; S2: coking and coking: then mix the fire area management residual coking coal, gas coal, 1# coking coal, 2# coking coal and 1 / 3 coking coal according to the proportion, and crush them by using a toothed roll crusher, then uniformly load the crushed mixed coal into the carbonization chamber through the coal loading car at the top of the coke oven, and then adjust the supply amount of coal gas and air in the combustion chamber of the coke oven to heat the coal in the carbonization chamber, so that the coal softens and melts in the carbonization chamber and solidifies into coke; S3: coke pushing and coke quenching: finally, the red coke in the carbonization chamber is pushed out by the coke pushing car and sent to the coke quenching tower for cooling, so that the coke is cooled to below 100℃.

[0008] The present application has the following advantages: (1) the present application refines metallurgical coke by utilizing residual coking coal obtained after Xinjiang 2130 coal mine area fire area management, and increases the proportion of fire area management residual coking coal to 20%-30%, thereby replacing traditional main coking coal with high price, reducing the cost of refining metallurgical coke, and reducing the cost of coal per ton of coke by more than 60 yuan; (2) by utilizing residual coking coal obtained after Xinjiang 2130 coal mine area fire area management and Xingmei gas coal, and by utilizing the high cold strength of residual coking coal obtained after Xinjiang 2130 coal mine area fire area management, the low thermal strength of fire area management residual coking coal is effectively compensated by Xingmei gas coal; (3) the coking process and coal blending method do not need to make major modifications to the existing production line, so it is easy to popularize, and the present application effectively activates the coal resources that are about to be wasted due to fire, reduces the accumulation of solid waste and the idle of resources, and conforms to the development direction of national green circular economy.

[0009] Scheme two, which is preferred in the basic scheme, in S1, the ash content Ad of the gas coal is ≤8.0%, the total sulfur St,d is ≤0.6%, and the caking index G is ≥90.

[0010] Scheme three, which is preferred in the basic scheme, in S1, the operation steps of the washing and dressing process are: Step one: screening and crushing: first, use a vibrating screen to remove large gangue and impurities in the residual coking coal obtained after the fire area treatment in the Xinjiang 2130 coal mine area, and then use a toothed roll crusher to crush the residual coking coal after removing impurities, so that the particle size is ≤50mm; Step two: dense medium separation: then send the crushed fire area treatment residual coking coal into a dense medium cyclone to further separate the coking coal and gangue, and the density of the suspension in the dense medium cyclone is 1.45-1.55 g / cm 3 ; Step three: desliming and flotation: then send the coking coal after further separation of gangue into a desliming screen, and use circulating water to wash the coking coal, so that the fine mud attached to the coking coal is removed, then send the coal slime water under the desliming screen into a flotation system, then add a collector and a frother to the coal slime water, so that the clean coal particles with low ash content in the coal slime water are separated; Step four: dewatering: finally, mix the clean coal obtained by dense medium separation with the clean coal particles obtained by flotation, and use a centrifugal dewatering machine for dewatering, so that the water content in the clean coal is <10%.

[0011] It can efficiently remove gangue, metal impurities and siliceous fine mud in raw coal, significantly reduce ash and sulfur content, and provide pure raw materials for subsequent coking.

[0012] Scheme four, which is preferred in the basic scheme, in S2, the proportion of the fire area treatment residual coking coal is 20%-30%, the proportion of the gas coal is 5%-15%, the proportion of the 1# coking coal is 20%-45%, the proportion of the 2# coking coal is 10%-30%, and the proportion of the 1 / 3 coking coal is 5%-10%; using the fire area treatment residual coking coal and increasing its amount for smelting coking, reduces the cost of smelting coking.

[0013] Scheme five, which is preferred in the basic scheme, in S2, the proportion of the coal material with a particle size of ≤3mm after crushing is 80%-85%; to ensure uniform and sufficient caking reaction of the coal material.

[0014] Scheme six, which is preferred in the basic scheme, in S2, the temperature of the combustion chamber of the coke oven is 1000-1050℃, the pressure at the top of the carbonization chamber is 5-10Pa, and the coking time of the coal material in the carbonization chamber is 20-24 hours; sufficient coking time can ensure sufficient pyrolysis and polycondensation of the coal material, and avoid green coke or overfire.

[0015] Option 7, which is a preferred option of the basic option, in S3, the coke pushing current of the coke pushing car is 180-220A; a stable current indicates that the coke cake is mature and uniform, the coke pushing resistance is small, and there is no difficulty in pushing. Attached Figure Description

[0016] Figure 1 This is a graph showing the variation trend of cold coking strength M40 and M10 of coke with proportion in a method for producing high-quality metallurgical coke from residual coking coal resources in the fire zone of Xinjiang 2130 coal mine according to the present invention. Figure 2 This is a graph showing the trend of coke hot strength (CSR) as a function of proportion in a method for producing high-quality metallurgical coke from residual coking coal resources in the fire zone of Xinjiang 2130 coal mine, as described in this invention. Detailed Implementation

[0017] The present invention will be further described in detail below through specific embodiments: Example 1 A method for producing high-quality metallurgical coke from residual coking coal resources in the fire zone of Xinjiang 2130 coal mine includes the following steps: S1: Raw Material Preparation and Pretreatment: First, prepare the residual coking coal, gas coal, No. 1 coking coal, No. 2 coking coal, and 1 / 3 coking coal obtained after the treatment of the fire zone in the Xinjiang 2130 coal mine area. Then, use a vibrating screen to remove large pieces of gangue and impurities from the residual coking coal obtained after the treatment of the fire zone in the Xinjiang 2130 coal mine area. Next, use a toothed roller crusher to crush the residual coking coal after removing impurities to a particle size ≤50mm. Then, send the crushed residual coking coal to a heavy medium hydrocyclone to further separate the coking coal from the gangue. The density of the suspension in the heavy medium hydrocyclone is 1.45-1.55 g / cm³. 3 The coking coal after further separation of gangue is then fed into a desliming screen, and the coking coal is washed with circulating water to remove the fine mud adhering to the coking coal. The coal slurry water that passes through the desliming screen is then sent to the flotation system. Collectors and frothers are added to the coal slurry water to separate the low-ash clean coal particles. Finally, the clean coal obtained from heavy media separation is mixed with the clean coal particles obtained from flotation and then dewatered using a centrifugal dewatering machine to make the moisture content of the clean coal <10%. Finally, the ash content Ad of the residual coking coal after washing and processing in the fire zone is ≤10.5%, total sulfur St,d≤0.4%, dry ash-free volatile matter Vdaf is 20.0%-25.0%, and caking index G≥80. S2: Coking and Coking: Then, 22% of the residual coking coal from the fire zone treatment, 10% of Xingmei gas coal, 45% of No. 1 coking coal, 13% of No. 2 coking coal, and 10% of 1 / 3 coking coal are mixed and crushed using a toothed roller crusher to make the proportion of mixed coal with a fineness of ≤3mm 83%. Then, the crushed mixed coal is evenly loaded into the carbonization chamber through the coal charging car at the top of the coke oven. The pressure at the top of the carbonization chamber is 5-10Pa. Then, the gas and air supply in the coke oven combustion chamber are adjusted to make the temperature of the coke oven combustion chamber 1030℃. Then, the coal in the carbonization chamber is heated so that the coal softens and melts in the carbonization chamber and then solidifies into coke. The coking time of the coal in the carbonization chamber is 23 hours. S3: Coke pushing and quenching: Finally, the red coke in the carbonization chamber is pushed out by the coke pushing car and sent to the quenching tower for cooling, so that the coke is cooled to below 100°C. The coke pushing current of the coke pushing car is 195A.

[0018] The coke produced by the above coking method has the following quality indicators: crush strength M40 is 89.5%, abrasion resistance M10 is 6.1%, hot strength CSR is 45.9%, dry basis ash content Ad is 12.50%, dry basis total sulfur St,d is 0.55%, and average coke particle size MS is 54.6 mm.

[0019] Example 2 A method for producing high-quality metallurgical coke from residual coking coal resources in the fire zone of Xinjiang 2130 coal mine is identical to the method in Example 1, except that: S2: Coking and Coking: Then, 26% of the residual coking coal from the fire zone treatment, 8% of the Xingmei gas coal, 35% of No. 1 coking coal, 21% of No. 2 coking coal, and 10% of 1 / 3 coking coal are mixed and crushed using a toothed roller crusher to make the proportion of mixed coal with a fineness of ≤3mm 82%. Then, the crushed mixed coal is evenly loaded into the carbonization chamber through the coal charging car at the top of the coke oven. The pressure at the top of the carbonization chamber is 5-10Pa. Then, the gas and air supply in the coke oven combustion chamber are adjusted to make the temperature of the coke oven combustion chamber 1030℃. Then, the coal in the carbonization chamber is heated so that the coal softens and melts in the carbonization chamber and then solidifies into coke. The coking time of the coal in the carbonization chamber is 23 hours. S3: Coke pushing and quenching: Finally, the red coke in the carbonization chamber is pushed out by the coke pushing car and sent to the quenching tower for cooling, so that the coke is cooled to below 100°C. The coke pushing current of the coke pushing car is 205A.

[0020] The coke produced by the above coking method has the following quality indicators: crush strength M40 is 89.3%, abrasion resistance M10 is 6.2%, hot strength CSR is 44.3%, dry basis ash content Ad is 12.25%, dry basis total sulfur St,d is 0.56%, and average coke particle size MS is 54.3 mm.

[0021] Example 3 A method for producing high-quality metallurgical coke from residual coking coal resources in the fire zone of Xinjiang 2130 coal mine is identical in steps to that in Example 1, except that: S2: Coking and Coking: Then, 10% of residual coking coal from the fire zone treatment, 47% of No. 1 coking coal, 13% of No. 2 coking coal, 10% of Wuhai fat coal, 10% of 1 / 3 coking coal, and 10% of gas coal are mixed and crushed using a toothed roller crusher. The crushed mixed coal is then evenly loaded into the carbonization chamber through the coal charging car at the top of the coke oven. The pressure at the top of the carbonization chamber is 5-10 Pa. Then, the gas and air supply in the coke oven combustion chamber are adjusted to make the temperature of the coke oven combustion chamber 1000-1050℃. Then, the coal in the carbonization chamber is heated so that the coal softens and melts in the carbonization chamber and then solidifies into coke. The coking time of the coal in the carbonization chamber is 20-24 hours. S3: Coke pushing and quenching: Finally, the red coke in the carbonization chamber is pushed out by the coke pushing car and sent to the quenching tower for cooling, so that the coke is cooled to below 100°C. The pushing current of the coke pushing car is 180-220A.

[0022] The coke produced by the above coking method has the following quality indicators: crush strength M40 is 89.1%, abrasion resistance M10 is 6.4%, hot strength CSR is 49.6%, dry basis ash content Ad is 12.60%, and dry basis total sulfur St,d is 0.65%.

[0023] Table 1: Comparison of Coke Quality Example number 1 2 3 Resistance to crushing strength (M40) 89.5% 89.3% 89.1% Resistance to abrasion strength (M10) 6.1% 6.2% 6.4% Hot state strength (CSR) 45.9% 44.3% 49.6% Dry base ash content (Ad) 12.50% 12.25% 12.60% Dry base total sulfur (St,d) 0.55% 0.56% 0.65% Average particle size (MS) 54.6 mm 54.3 mm 54.1 mm In Table 1, the metallurgical coke refined by Example 1 has a crush resistance strength M40 of 89.5%, an abrasion resistance strength M10 of 6.1%, and a dry basis total sulfur (St,d) of 0.55%, all of which are superior to the quality indicators of the metallurgical coke refined by Examples 2 and 3. The metallurgical coke refined by Example 2 has a dry basis ash content Ad of 12.25%, which is superior to the dry basis ash content of the metallurgical coke refined by Examples 1 and 3. The metallurgical coke refined by Example 3 has a hot strength CSR of 49.6%, which is superior to the hot strength of the metallurgical coke refined by Examples 1 and 2.

[0024] In summary, the metallurgical coke produced by Examples 1, 2, and 3 all exhibited a crush resistance (M40) greater than 89%, an abrasion resistance (M10) less than 6.5%, a hot strength (CSR) greater than 44%, a dry basis ash content (Ad) less than 12.5%, and a dry basis total sulfur content (St,d) less than 0.8%. All three metallurgical cokes produced by Examples 1, 2, and 3 meet the quality standards for high-quality metallurgical coke. The coal blending costs per ton of metallurgical coke in Examples 1 and 2 were RMB 1222.5 and RMB 1288.9, respectively. Therefore, compared to Examples 2 and 3, Example 1 had the lowest coal blending cost while still meeting the quality standards for high-quality metallurgical coke.

[0025] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for producing high-quality metallurgical coke from residual coking coal resources in the fire zone of Xinjiang 2130 coal mine, characterized in that, Includes the following steps: S1: Raw material preparation and pretreatment: First, prepare the residual coking coal, gas coal, No. 1 coking coal, No. 2 coking coal and 1 / 3 coking coal obtained after the fire zone treatment in Xinjiang 2130 coal mine area. Then, wash and process the residual coking coal after the fire zone treatment to make the ash content Ad≤10.5%, total sulfur St,d≤0.4%, dry ash-free volatile matter Vdaf20.0%-25.0%, and caking index G≥80. S2: Coking and Coking: Then, the residual coking coal, gas coal, No. 1 coking coal, No. 2 coking coal and 1 / 3 coking coal from the fire zone are mixed in proportion and crushed using a toothed roller crusher. Then, the crushed mixed coal is evenly loaded into the carbonization chamber through the coal charging car at the top of the coke oven. Then, the supply of gas and air in the coke oven combustion chamber is adjusted to heat the coal in the carbonization chamber, so that the coal softens and melts in the carbonization chamber and then solidifies into coke. S3: Coke pushing and quenching: Finally, the red coke in the carbonization chamber is pushed out by the coke pushing car and sent to the quenching tower for cooling, so that the coke is cooled to below 100°C.

2. The method for producing high-quality metallurgical coke from residual coking coal resources in the fire zone of Xinjiang 2130 coal mine according to claim 1, characterized in that, In S1, the ash content Ad of the gas coal is ≤8.0%, the total sulfur St,d is ≤0.6%, and the caking index G is ≥90.

3. A method for producing high-quality metallurgical coke from residual coking coal resources in the fire zone of Xinjiang 2130 coal mine according to claim 1, characterized in that, In S1, the washing and screening process steps are as follows: Step 1: Screening and Crushing: First, a vibrating screen is used to remove large pieces of gangue and impurities from the residual coking coal obtained after the fire zone treatment in Xinjiang 2130 coal mine area. Then, a toothed roller crusher is used to crush the residual coking coal after the fire zone treatment to remove impurities, so that the particle size is ≤50mm. Step Two: Heavy Medium Separation: Next, the crushed residual coking coal from the fire zone treatment is fed into a heavy medium hydrocyclone to further separate the coking coal from the gangue. The density of the suspension in the heavy medium hydrocyclone is 1.45-1.55 g / cm³. 3 ; Step 3: Desliming and flotation: The coking coal after further separation of gangue is then fed into a desliming screen and washed with circulating water to remove the fine mud adhering to the coking coal. The coal slurry water that passes through the desliming screen is then sent into the flotation system. Collectors and frothers are then added to the coal slurry water to separate the low-ash clean coal particles. Step 4: Dewatering: Finally, the clean coal obtained from heavy media separation is mixed with the clean coal particles obtained from flotation and then dewatered using a centrifugal dewatering machine to make the moisture content in the clean coal <10%.

4. A method for producing high-quality metallurgical coke from residual coking coal resources in the fire zone of Xinjiang 2130 coal mine according to claim 1, characterized in that, In S2, the proportion of residual coking coal in the fire zone treatment is 20%-30%, the proportion of gas coal is 5%-15%, the proportion of No. 1 coking coal is 20%-45%, the proportion of No. 2 coking coal is 10%-30%, and the proportion of 1 / 3 coking coal is 5%-10%.

5. A method for producing high-quality metallurgical coke from residual coking coal resources in the fire zone of Xinjiang 2130 coal mine according to claim 1, characterized in that, In S2, the proportion of coal with a fineness of ≤3mm after crushing is 80%-85%.

6. A method for producing high-quality metallurgical coke from residual coking coal resources in the fire zone of Xinjiang 2130 coal mine according to claim 1, characterized in that, In S2, the temperature of the coke oven combustion chamber is 1000-1050℃, the pressure at the top of the carbonization chamber is 5-10Pa, and the coking time of the coal in the carbonization chamber is 20-24 hours.

7. A method for producing high-quality metallurgical coke from residual coking coal resources in the fire zone of Xinjiang 2130 coal mine according to claim 1, characterized in that, In S3, the coking current of the coking carriage is 180-220A.

Images