Coke coal blending and coking method suitable for 6.78 m tamping coke oven

Abstract

The invention discloses a coke coal blending coking method suitable for a 6.78 m tamping coke oven. The method comprises the following steps: (1) coal blending; (2) crushing: crushing the mixed coal; (3) tamping: making the crushed mixed coal into coal cakes by using a tamping machine; (4) coking: loading the prepared coal cake into a coke oven for coking; (5) quenching: loading the mature coke into a dry quenching furnace for quenching to obtain a coke finished product; and (6) transferring and storing: transferring the quenched coke to a coke bin. The method has the beneficial effects that by adjusting the proportion of the mixed coal and the particle size of the mixed coal after crushing, and combining optimization of tamping briquette process parameters and optimization of coking process parameters, the coke powder content of a 6.78 m tamping coke oven is reduced to 8% or below, and the average particle size of the coke is 48 mm-50 mm; and the coal collapse rate of the coal cake is reduced to 4% or below, and high-quality coke is prepared while the production efficiency is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of coal blending and coking, and in particular to a coke blending and coking method suitable for a 6.78-meter ramming coke oven. Background Art

[0002] In the coking industry, coal is converted into coke through a high-temperature dry distillation process, which inevitably produces coke powder. The production of coke powder mainly includes the following situations: (1) In the coking process, due to insufficient liquid phase or uneven liquid phase flow, the infusible materials cannot be completely bonded and condensed together, and part of the infusible materials will produce coke powder; (2) When the semi-coke shrinks to form coke, the coke breaks due to the effect of internal stress, resulting in coke fragments and fines; (3) After the coke matures, it falls off when pushing the coke, resulting in fragments and powder; (4) Fragments and powder are produced by falling and friction during coke transportation, and shearing during coke granulation.

[0003] When using a 4.3-meter coke oven for coking coal blending, each type of coal is blended according to the following mass proportions: 28 to 32 parts of high volatile coal, 68 to 72 parts of fat coking coal, the coking temperature is 1345℃~1350℃, the coking time is 23.5h~24.5h, the powder content of the coke produced is 7.36%~8.41%, and the average particle size of the coke is 46mm~48mm.

[0004] In order to improve production efficiency, improve coke quality, reduce energy consumption and meet environmental protection requirements, 4.3-meter rammed coke ovens are gradually phased out, and the furnace size of newly added rammed coke ovens is also increased from 4.3 meters to 6.78 meters. The 6.78-meter rammed coke oven is used for coking. Due to the larger furnace body, the coal blending and coking methods of the 4.3-meter rammed coke oven are still used. The average coke powder content increases from 7.79% to 10.18%; and due to the increase in furnace size, the rammed coal cakes collapse and fall off seriously, and the average coal collapse rate of coal cakes increases from 4% to 8%. Therefore, it is necessary to develop a coal blending and coking method suitable for 6.78-meter rammed coke ovens. Summary of the invention

[0005] In order to solve the above technical problems, the purpose of the present invention is to provide a coke blending and coking method suitable for a 6.78-meter ramming coke oven. By adjusting the proportion of the blended coal, the particle size of the blended coal after crushing, and carrying out ramming coking, the problems of high coal collapse rate and high powder content in the produced coke in the 6.78-meter ramming coke oven can be effectively solved.

[0006] The technical solution adopted by the present invention is: The coke blending and coal coking method applicable to a 6.78-meter ramming coke oven comprises the following steps: (1) Coal blending: each type of coal is blended according to the following mass proportions to obtain the blended coal: 5 to 12 parts of weakly caking coal, 15 to 25 parts of 1 / 3 coking coal, 2 to 6 parts of fat coal, 10 to 23 parts of gas coal, 5 to 9 parts of coking coal A, 10 to 25 parts of coking coal B, 5 to 10 parts of coking coal C, and 12 to 18 parts of lean coal; (2) crushing: crushing the blended coal; (3) Tamping: using a tamping machine to make briquettes from the crushed blended coal; (4) Coking: the prepared coal cakes are loaded into a coke oven for coking at a coking temperature of 1330°C to 1337°C and a coking time of 26.5h to 29.5h; (5) Quenching: loading the mature coke into a dry quenching furnace for quenching to obtain finished coke; (6) Transportation and storage: the quenched coke is transported to the coke bin.

[0007] Preferably, in step (1), the ash yield of the weakly sticky coal is 4% to 6%, the volatile matter is 28% to 37%, the total sulfur content is 0.5% to 0.7%, there is no clear requirement for the Y value, and the G value is 5 to 30; 1 / 3 coking coal has an ash yield of 5%~10%, volatile matter of 28%~37%, total sulfur content of 0.5%~0.7%, Y value of 10mm~25mm, and G value of 65~85; The ash yield of fat coal is 5%~10%, the volatile matter is 28%~37%, the total sulfur content is not higher than 2.9%, the Y value is not less than 25mm, and the G value is not less than 85; The ash yield of gas coal is 9%~10.5%, the volatile matter is 30%~37%, the total sulfur content is 0.4%~0.6%, the Y value is 14mm~25mm, and the G value is 65~85; The ash yield of coking coal A is 9%~11%, the volatile matter is 20%~28%, the total sulfur content is 0.6%~1.6%, the Y value is 14mm~25mm, and the G value is 65~85; The ash yield of coking coal B is 9%~11%, the volatile matter is 20%~28%, the total sulfur content is 0.5%~1%, the Y value is 14mm~25mm, and the G value is 65~85; The ash yield of coking coal C is 9%~11%, the volatile matter is 20%~28%, the total sulfur content is 1%~1.8%, the Y value is 20mm~25mm, and the G value is 85~98; The ash yield of lean coal is 5%~11%, the volatile matter is 10%~20%, the total sulfur content is 0.5%~0.8%, there is no clear requirement for the Y value, and there is no clear requirement for the G value.

[0008] Preferably, in step (2), after crushing, the moisture content of the blended coal is controlled to 11% to 13% by drying or adding water.

[0009] Preferably, in step (2), the particle size of the crushed blended coal is less than 3.0 mm, accounting for 82% to 90%.

[0010] Preferably, in step (3), a shaking feeder is used to continuously feed in a thin layer, 5 groups of 38 tamping hammers are used, the tamping frequency is not less than 72 times / min, the tamping time is not shorter than 660 seconds, and the bulk density of the coal cakes after tamping is controlled to be not less than 1.035 t / m³.

[0011] Preferably, in step (6), the powder content of the finished coke is below 8%, the average particle size of the coke is 48 mm to 50 mm, the proportion of coke with a particle size > 80 mm is 2.3% to 5.3%, the proportion of coke with a particle size of 60 mm to 80 mm is 13% to 20%, the proportion of coke with a particle size of 40 mm to 60 mm is 32% to 50%, the proportion of coke with a particle size of 25 mm to 40 mm is 18% to 24%, the proportion of coke with a particle size < 25 mm is 8% to 13%, and the proportion of coke with a particle size < 10 mm is no more than 8%.

[0012] Preferably, in step (6), the coke product has a coke reaction strength CSR greater than 65%, a coke reaction index CRI less than 23.5%, and a coke crushing strength M 40 Greater than 84%.

[0013] The invention has the advantages that by adjusting the proportion of the blended coal and the particle size of the blended coal after crushing, combined with the optimization of the process parameters of the tamping coal cake and the optimization of the coking process parameters, the powder content of coke in the 6.78-meter tamping coke oven is reduced to less than 8%, the average particle size of the coke is 48mm-50mm, the proportion of coke with a particle size of more than 80mm is 2.3%-5.3%, the proportion of coke with a particle size of 60mm-80mm is 13%-20%, the proportion of coke with a particle size of 40mm-60mm is 32%-50%, the proportion of coke with a particle size of 25mm-40mm is 18%-24%, the proportion of coke with a particle size of less than 25mm is 8%-13%, and the proportion of coke with a particle size of less than 10mm is no more than 8%; the coal collapse rate of the coal cake is reduced to less than 4%, and the coke is obtained while ensuring the production efficiency. The coke finished product has a coke reaction strength CSR greater than 65%, a coke reaction index CRI less than 23.5%, and a coke crushing strength M 40 Greater than 84%. DETAILED DESCRIPTION

[0014] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] This embodiment mainly aims at the problems that the furnace size of the ramming coke oven is increased from 4.3 meters to 6.78 meters, the coke powder content, that is, the proportion of coke with a particle size of less than 10 mm, increases from an average of 7.79% to 10.18%, and the coal cake collapse rate increases from an average of 4% to 8%. Measures such as selecting suitable coal types and making reasonable proportions, controlling the coking temperature and time, controlling the moisture content of the blended coal, and optimizing the process parameters of ramming coal cakes are proposed to reduce the coke powder content and the coal cake collapse rate, and a coke blending method suitable for a 6.78-meter ramming coke oven is proposed.

[0016] Example: The coke blending and coal coking method applicable to a 6.78-meter ramming coke oven comprises the following steps: (1) Coal blending: the performance parameters of each type of coal are shown in Table 1, and the mass proportion of each type of coal is shown in Table 2; (2) Crushing: crushing the blended coal. The blended coal particles with a particle size of less than 3.0 mm account for 82% to 90% of the crushed blended coal. The moisture content of the blended coal is adjusted by drying or adding water. The moisture content of the blended coal is shown in Table 3. (3) Tamping: the crushed blended coal is made into briquettes by a tamping machine, and the briquettes are fed in thin layers continuously by a shaking feeder. The tamping frequency of 5 groups of 38 hammers is not less than 72 times / min, and the tamping time is not less than 660 seconds. The bulk density of the briquettes after tamping is controlled as shown in Table 3; (4) Coking: the prepared coal cakes are loaded into a coke oven for coking. The specific coking temperature and coking time are shown in Table 3; (5) Quenching: loading the mature coke into a dry quenching furnace for quenching to obtain finished coke; (6) Transportation and storage: the quenched coke is transported to the coke bin.

[0017] Coking coal A, coking coal B and coking coal C are all coking coals. The main differences between them are the total sulfur content and caking index. The three types of coking coal are used at the same time to adjust the total sulfur content, coking performance and control the price of the blended coal.

[0018] The performance parameters of the coke prepared by the above-mentioned coke blending and coking method suitable for a 6.78-meter ramming coke oven are shown in Table 4.

[0019] As shown in Table 4, by selecting appropriate coal types and making reasonable proportions, controlling coking temperature, coking time, coal cake density, coal moisture and other coking process parameters, and then coking, the cokes produced by Schemes 1 to 10 have a coke reaction strength CSR greater than 65%, a coke reaction index CRI less than 23.5%, and a coke crushing strength M 40All are greater than 84%, the coke powder content is below 8%, the average coke particle size is between 48mm and 50mm, and the coal briquettes collapse rate is below 4%.

[0020] Comparative Example 1: The method for coking with coke blended with coal in a 4.3-meter ramming coke oven comprises the following steps: (1) Coal blending: the performance parameters of each type of coal are shown in Table 1, and the mass proportion of each type of coal is shown in Table 5; (2) Crushing: crushing the blended coal. The blended coal particles with a particle size of less than 3.0 mm account for 82% to 90% of the crushed blended coal. The moisture content of the blended coal is adjusted by drying or adding water. The moisture content of the blended coal is shown in Table 6. (3) Tamping: the crushed blended coal is made into briquettes using a tamping machine. The bulk density of the briquettes after tamping is shown in Table 6; (4) Coking: the prepared coal cakes are loaded into a coke oven for coking. The specific coking temperature and coking time are shown in Table 6; (5) Quenching, wet quenching of mature coke to obtain finished coke; (6) Transportation and storage: the quenched coke is transported to the coke bin.

[0021] The performance parameters of the prepared coke are shown in Table 7. The coke prepared in Scheme 1 has a coke strength after reaction of 67.8%, a coke reaction index of 22.4%, and a coke crushing strength of M. 40 The coal powder content is 87.6%, the coke powder content is 7.89%, the average coke particle size is 47.3mm, and the coal briquettes collapse rate is 3.75%.

[0022] Comparative Example 2: The difference between this comparative example and comparative example 1 is that the ramming coke oven is different, and coking is carried out in a 6.78 m ramming coke oven, comprising the following steps: (1) Coal blending: the performance parameters of each type of coal are shown in Table 1, and the mass proportion of each type of coal is shown in Table 5; (2) Crushing: crushing the blended coal. The blended coal particles with a particle size of less than 3.0 mm account for 82% to 90% of the crushed blended coal. The moisture content of the blended coal is adjusted by drying or adding water. The moisture content of the blended coal is shown in Table 6. (3) Tamping: the crushed blended coal is made into briquettes using a tamping machine. The bulk density of the briquettes after tamping is shown in Table 6; (4) Coking: the prepared coal cakes are loaded into a coke oven for coking. The specific coking temperature and coking time are shown in Table 6; (5) Quenching: loading the mature coke into a dry quenching furnace for quenching to obtain finished coke; (6) Transportation and storage: the quenched coke is transported to the coke bin.

[0023] The performance parameters of the prepared coke are shown in Table 8. The coke prepared in Scheme 1 has a coke strength after reaction of 58.3%, a coke reaction index of 25.4%, and a coke crushing strength of M. 40 The coke powder content is 82.6%, the coke powder content is 9.83%, the average coke particle size is 45.1 mm, and the coal cake collapse rate is 8.68%; compared with the embodiment scheme 1 to scheme 10, the coke post-reaction strength CSR and the coke crushing strength M 40 , the average particle size of coke was significantly reduced, and the coke reaction index CRI, coke powder content and coal cake collapse rate were significantly increased.

[0024] Comparative Example 3: A 6.78-meter ramming coke oven was used for coking. The difference between this comparative example and the embodiment lies in the adjustment of coal blending and coking process parameters such as coal type ratio, coking temperature, coking time, coal cake bulk density, and mixed coal moisture.

[0025] The following steps are involved: (1) Coal blending: the performance parameters of each type of coal are shown in Table 1, and the mass proportion of each type of coal is shown in Table 9; (2) Crushing: crushing the blended coal. The blended coal particles with a particle size of less than 3.0 mm account for 82% to 90% of the crushed blended coal. The moisture content of the blended coal is adjusted by drying or adding water. The moisture content of the blended coal is shown in Table 10. (3) Tamping: the crushed blended coal is made into briquettes using a tamping machine. The bulk density of the briquettes after tamping is shown in Table 10; (4) Coking: the prepared coal cakes are loaded into a coke oven for coking. The specific coking temperature and coking time are shown in Table 10; (5) Quenching: loading the mature coke into a dry quenching furnace for quenching to obtain finished coke; (6) Transportation and storage: the quenched coke is transported to the coke bin.

[0026] The performance parameters of the coke prepared by coking in the 6.78 m ramming coke oven are shown in Table 11.

[0027] As shown in Table 11, the coke produced by Scheme 1 and Scheme 2 in a 6.78 m ramming coke oven has a coke strength after reaction (CSR) less than 65%, a coke reaction index (CRI) greater than 23.5%, and a coke crushing strength (M). 40 The coke powder content is all less than 84%, the coke average particle size is all less than 48 mm, and the coal cake collapse rate is all above 4%, indicating that the adjustment of the proportion of mixed coal mass has an impact on the coke reaction strength CSR, coke reaction index CRI, and coke crushing strength M. 40 , coke powder content, coke average particle size, coal cake collapse rate; The coke produced by Scheme 3 and Scheme 4 has a post-reaction strength CSR less than 65%, a reaction index CRI greater than 23.5%, and a crushing strength M 40 The coke powder content was all above 8%, the average coke particle size was all below 48 mm, and the coal cake collapse rate was all below 4%, indicating that the adjustment of the coking temperature had a significant effect on the coke reaction strength CSR, coke reaction index CRI, and coke crushing strength M. 40 , coke powder content, and coke average particle size; The coke produced by Scheme 5 and Scheme 6 has a post-reaction strength CSR less than 65%, a reaction index CRI greater than 23.5%, and a crushing strength M 40 The coke powder content was all above 8%, the average coke particle size was all below 48 mm, and the coal cake collapse rate was all below 4%, indicating that the adjustment of coking time had a significant effect on the coke reaction strength CSR, coke reaction index CRI, and coke crushing strength M. 40 , coke powder content, and coke average particle size; The coke produced in Scheme 7 has a post-reaction strength CSR greater than 65%, a reaction index CRI less than 23.5%, and a crushing strength M 40 greater than 84%, the coke powder content is above 8%, the average coke particle size is less than 48mm, and the coal briquettes collapse rate is above 4%, indicating that adjusting the coal briquettes stacking density has an impact on the coke powder content, the average coke particle size, and the coal briquettes collapse rate; The coke produced by Scheme 8 and Scheme 9 has a post-reaction strength CSR less than 65%, a reaction index CRI greater than 23.5%, and a crushing strength M 40 The coke powder content of Scheme 8 is above 8%, and that of Scheme 9 is below 8%. The average coke particle size of Scheme 8 is less than 48 mm, and that of Scheme 9 is above 48 mm. The coal collapse rate of Scheme 8 is above 4%, and that of Scheme 9 is below 4%. This indicates that adjusting the moisture content of the blended coal has an impact on the coke post-reaction strength CSR, coke reaction index CRI, coke powder content, coke average particle size and coal collapse rate.

[0028] Table 1: Performance parameters of each single coal type

[0029] Table 2: Mass proportion of each coal type in the embodiment

[0030] Table 3: Coking parameters of different proportions of coal in the embodiment

[0031] Table 4: Performance parameters of coke obtained from different coking schemes of the embodiment

[0032] Table 5: Mass proportion of each type of coal in Comparative Example 1 and Comparative Example 2

[0033] Table 6: Coking parameters of Comparative Example 1 and Comparative Example 2

[0034] Table 7: Coke performance parameters of Comparative Example 1

[0035] Table 8: Coke performance parameters of Comparative Example 2

[0036] Table 9: Mass proportion of each type of coal in comparative example 3

[0037] Table 10: Coking parameters of different proportions of coal in comparative example 3

[0038] Table 11: Performance parameters of coke obtained from different coking schemes of Comparative Example 3

[0039] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A coke blending and coal coking method applicable to a 6.78 m ramming coke oven, comprising the following steps: (1) Coal blending: each type of coal is blended according to the following mass proportions to obtain the blended coal: 5 to 12 parts of weakly caking coal, 15 to 25 parts of 1 / 3 coking coal, 2 to 6 parts of fat coal, 10 to 23 parts of gas coal, 5 to 9 parts of coking coal A, 10 to 25 parts of coking coal B, 5 to 10 parts of coking coal C, and 12 to 18 parts of lean coal; (2) crushing: crushing the blended coal; (3) Tamping: using a tamping machine to make briquettes from the crushed blended coal; (4) Coking: the prepared coal cakes are loaded into a coke oven for coking at a coking temperature of 1330°C to 1337°C and a coking time of 26.5h to 29.5h; (5) Quenching: loading the mature coke into a dry quenching furnace for quenching to obtain finished coke; (6) Transportation and storage: the quenched coke is transported to the coke bin.

2. The coke blending and coal coking method suitable for a 6.78 m ramming coke oven according to claim 1, characterized in that: In step (1), the ash yield of the weakly caking coal is 4% to 6%, the volatile matter is 28% to 37%, the total sulfur content is 0.5% to 0.7%, there is no clear requirement for the Y value, and the G value is 5 to 30; 1 / 3 coking coal has an ash yield of 5%~10%, volatile matter of 28%~37%, total sulfur content of 0.5%~0.7%, Y value of 10mm~25mm, and G value of 65~85; The ash yield of fat coal is 5%~10%, the volatile matter is 28%~37%, the total sulfur content is not higher than 2.9%, the Y value is not less than 25mm, and the G value is not less than 85; The ash yield of gas coal is 9%~10.5%, the volatile matter is 30%~37%, the total sulfur content is 0.4%~0.6%, the Y value is 14mm~25mm, and the G value is 65~85; The ash yield of coking coal A is 9%~11%, the volatile matter is 20%~28%, the total sulfur content is 0.6%~1.6%, the Y value is 14mm~25mm, and the G value is 65~85; The ash yield of coking coal B is 9%~11%, the volatile matter is 20%~28%, the total sulfur content is 0.5%~1%, the Y value is 14mm~25mm, and the G value is 65~85; The ash yield of coking coal C is 9%~11%, the volatile matter is 20%~28%, the total sulfur content is 1%~1.8%, the Y value is 20mm~25mm, and the G value is 85~98; The ash yield of lean coal is 5%~11%, the volatile matter is 10%~20%, the total sulfur content is 0.5%~0.8%, there is no clear requirement for the Y value, and there is no clear requirement for the G value.

3. The coke blending and coal coking method suitable for a 6.78 m ramming coke oven according to claim 1, characterized in that: In step (2), after crushing, the moisture content of the blended coal is controlled to 11% to 13% by drying or adding water.

4. The coke blending and coal coking method suitable for a 6.78 m ramming coke oven according to claim 1, characterized in that: In step (2), the particle size of the crushed blended coal is less than 3.0 mm, accounting for 82% to 90%.

5. The coke blending and coal coking method applicable to a 6.78 m ramming coke oven according to claim 1, characterized in that: In step (3), a shaking feeder is used to continuously feed in a thin layer, 5 groups of 38 tamping hammers are used, the tamping frequency is not less than 72 times / min, the tamping time is not less than 660 seconds, and the coal cake bulk density after tamping is controlled to be not less than 1.035 t / m³.

6. The coke blending and coal coking method applicable to a 6.78 m ramming coke oven according to claim 1, characterized in that: In step (6), the powder content of the finished coke is below 8%, the average particle size of the coke is 48mm-50mm, the proportion of coke with a particle size of more than 80mm is 2.3%-5.3%, the proportion of coke with a particle size of 60mm-80mm is 13%-20%, the proportion of coke with a particle size of 40mm-60mm is 32%-50%, the proportion of coke with a particle size of 25mm-40mm is 18%-24%, the proportion of coke with a particle size of less than 25mm is 8%-13%, and the proportion of coke with a particle size of less than 10mm is no more than 8%.

7. The coke blending and coal coking method applicable to a 6.78 m ramming coke oven according to claim 1, characterized in that: In step (6), the coke product has a coke reaction strength CSR greater than 65%, a coke reaction index CRI less than 23.5%, and a coke crushing strength M 40 Greater than 84%.

Images