Coal blending optimization method for stabilizing coke quality

Abstract

The invention relates to a coal blending optimization method for stabilizing coke quality, and belongs to the technical field of coking coal blending methods. According to the technical scheme, the method comprises the following steps: regularly detecting indexes of N single coals participating in coal blending; updating the index of each single coal in the coal blending scheme; calculating the corrected indexes of the blended coal in the coal blending scheme; determining whether to carry out the next step or not according to the corrected indexes of the blended coal; different coal blending schemes are newly formulated; determining the post-reaction strength of coke corresponding to each coal blending scheme to determine whether to carry out the next step; the strength of the corresponding coke after reaction before the coal blending scheme is adjusted is used as a reference for optimization selection of the coal blending scheme; and calculating the ratio of the strength of the coke after reaction corresponding to each coal blending scheme to the reference, and taking the coal blending scheme with the large ratio value as an optimal scheme. The method has the beneficial effects that the problem of unstable coke quality is solved by timely correcting the proportion of the single coal participating in coal blending in the coal blending scheme, optimizing the parameters in the coal blending process and controlling the influence caused by interference factors in the coal blending process.

Description

Technical Field

[0001] The invention relates to a coal blending optimization method for stabilizing coke quality, and belongs to the technical field of coking coal blending methods. Background Art

[0002] Coal blending is one of the processes for preparing coking coal and an important preparation process for coal before coking. That is, in order to produce coke that meets the quality requirements, different grades of coking coal are blended in appropriate proportions. Considering market factors and the company's operating benefits, coking coal blending continues to expand resources and enrich varieties. The current situation of many types of coking coal, large differences in quality, and unstable supply quantity has brought great difficulties to coal blending management. At present, there are 15 types of coking coal used by our company, among which the highest ash content is 11.6% and the lowest is 6.0%, the highest volatile content is more than 37.3% and the lowest is 10.6%, the highest sulfur content is 2.1% and the lowest is 0.1%, the highest moisture content is 16.5% and the lowest is 10.8%, the coking and bonding properties are also quite different, and the coal blending parameters of each single coal tested each time fluctuate frequently, resulting in the quality fluctuation of coke obtained by coking. In order to cope with the quality changes of each single coal, it is necessary to adjust the coal blending ratio. Moreover, the coking industry lacks relevant coal blending structure optimization methods, which leads to coal blending operators blindly adjusting coal blending plans, causing fluctuations in the strength of coke produced by the coke oven after reaction, affecting the smooth operation of the blast furnace. Summary of the invention

[0003] The object of the present invention is to provide a method for optimizing coal blending for stabilizing the quality of coke. By regularly detecting the indicators of single coals involved in coal blending, timely correcting the proportions of single coals involved in the coal blending scheme, optimizing the parameters of the coal blending process, and controlling the influence of interference factors in the coal blending process, the problem of unstable coke quality is solved; and a coal blending scheme is formulated according to the needs of coke quality, the post-reaction strength of coke corresponding to the coal blending scheme is determined, and the corresponding post-reaction strength of coke before the coal blending scheme is adjusted is used as the benchmark for optimizing the coal blending scheme. The ratio of the post-reaction strength of coke corresponding to each coal blending scheme to the benchmark is used as the basis for optimization, and the coal blending scheme with a large ratio value is selected as the preferred scheme, which solves the problem of the coal blending operator blindly adjusting the coal blending scheme and causing the post-reaction strength of coke produced by the coke oven to fluctuate, and effectively solves the above-mentioned problems existing in the background technology.

[0004] The technical solution of the present invention is: a method for optimizing coal blending for stabilizing coke quality, comprising the following steps:

[0005] (1) Regularly test the indicators of N types of coal involved in coal blending; (2) Update the indicators of each type of coal in the coal blending plan; (3) Calculate the revised indicators of the blended coal in the coal blending plan; (4) Decide whether to proceed to the next step based on the revised indicators of the blended coal; (5) Formulate different coal blending plans; (6) Determine the coke reaction strength corresponding to each coal blending plan to determine whether to proceed to the next step; (7) Use the corresponding coke reaction strength before the adjustment of the coal blending plan as the benchmark for optimizing the coal blending plan; (8) Calculate the ratio of the coke reaction strength corresponding to each coal blending plan to the benchmark, and select the coal blending plan with the largest ratio as the preferred plan.

[0006] The blended coal in the coal blending scheme includes different combinations of lean coal, fat coal, 1 / 3 coking coal, coking coal, high-sulfur coking coal and gas coal.

[0007] In the step (1), the indexes of a single type of coal are tested in accordance with GB / T 212-2008 "Industrial analysis and determination methods for coal", GB / T 214-2007 "Determination method for total sulfur in coal" and GB / T 5447-2014 "Determination method for cohesiveness index of bituminous coal".

[0008] In the step (2), according to the dry basis coal blending ratios P1, P2, P3, P4, ..., P N , calculate the corrected proportion P of N single coals involved in coal blending N ', that is, P N '=(P N / (1-Mt N )) / (P1 / (1-Mt1)+P2 / (1-Mt2)+P3 / (1-Mt3)+P4 / (1-Mt4)………+P N / (1-Mt N )).

[0009] In the step (3), the corrected index of the blended coal in the coal blending scheme is calculated, i.e., Ad = ∑(Ad N ×P N ')÷∑P N '; Vdaf = ∑ (Vdaf N ×P N ')÷∑P N '; St.d = ∑(St.d N ×P N ')÷∑P N '; G = ∑ (G N ×P N ')÷∑P N '.

[0010] In step (4), if the corrected index of the blended coal satisfies Ad<Ad 设定 , Vdaf设定1 <Vdaf<Vdaf 设定2 , St.d<St.d 设定 and G>G 设定 , then the N kinds of coal in the coal blending plan are adjusted according to the modified proportion P N 'Coal blending; if one or more of the corrected indicators of the blended coal do not meet Ad<Ad 设定 , Vdaf 设定1 <Vdaf<Vdaf 设定2 , St.d<St.d 设定 and G>G 设定 , then proceed to the next step.

[0011] In step (6), when CSR i <CSR 设定 When the corresponding coal blending plan is invalid; when CSR i ≥CSR 设定 When the corresponding coal blending scheme is used as an alternative, the next step is carried out, in which CSR i is the strength of coke after reaction, CSR 设定 Set the value for the strength of coke after reaction.

[0012] In the step (6), firstly, N single types of coals involved in coal blending are collected and crushed to control the fineness of the coals to 74±3%, and then mixed according to the coal blending ratio of the coal blending scheme, and evenly mixed after three batch blending, and the moisture content is controlled at 10±1%. Then, the blended coal is loaded into a 40kg test coke oven for coking; 25kg of coke with a particle size greater than 25mm and less than 60mm produced by the 40kg test coke oven is taken in proportion, and then the post-reaction strength of the coke sample is tested in accordance with GB / T4000-2017 "Test Method for Reactivity and Post-Reaction Strength of Coke".

[0013] The time interval for correcting the proportion calibration of the coal blending scheme is 24 to 48 hours.

[0014] The correction ratio calibration of the coal blending scheme is to perform steps (1) to (8) on the coal blending scheme again.

[0015] The beneficial effects of the present invention are as follows: by regularly detecting the indicators of single types of coal involved in coal blending, timely correcting the proportions of single types of coal involved in the coal blending plan, optimizing the parameters of the coal blending process, and controlling the influence of interference factors in the coal blending process, the problem of unstable coke quality is solved; and a coal blending plan is formulated according to the needs of coke quality, the post-reaction strength of coke corresponding to the coal blending plan is determined, and the corresponding post-reaction strength of coke before the coal blending plan is adjusted is used as the benchmark for optimizing the coal blending plan. The ratio of the post-reaction strength of coke corresponding to each coal blending plan to the benchmark is used as the basis for optimization, and the coal blending plan with a large ratio value is selected as the preferred plan, which solves the problem of the coal blending operator blindly adjusting the coal blending plan and causing the post-reaction strength of coke produced by the coke oven to fluctuate. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a method flow chart of an embodiment of the present invention. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solutions and advantages of the invention implementation cases clearer, the technical solutions in the implementation cases of the present invention will be clearly and completely described below in conjunction with the drawings in the implementation cases. Obviously, the implementation cases described are only a small part of the implementation cases of the present invention, rather than all the implementation cases. Based on the implementation cases in the present invention, all other implementation cases obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0018] A method for optimizing coal blending for stabilizing coke quality comprises the following steps: (1) regularly testing the indicators of N types of coal involved in coal blending; (2) updating the indicators of each type of coal in the coal blending scheme; (3) calculating the revised indicators of the blended coal in the coal blending scheme; (4) determining whether to proceed to the next step based on the revised indicators of the blended coal; (5) formulating different coal blending schemes; (6) determining the coke post-reaction strength corresponding to each coal blending scheme to determine whether to proceed to the next step; (7) using the corresponding coke post-reaction strength before the coal blending scheme is adjusted as a benchmark for optimizing the coal blending scheme; (8) calculating the ratio of the coke post-reaction strength corresponding to each coal blending scheme to the benchmark, and selecting the coal blending scheme with the largest ratio as the preferred scheme.

[0019] The blended coal in the coal blending scheme includes different combinations of lean coal, fat coal, 1 / 3 coking coal, coking coal, high-sulfur coking coal and gas coal.

[0020] In the step (1), the indexes of a single type of coal are tested in accordance with GB / T 212-2008 "Industrial analysis and determination methods for coal", GB / T 214-2007 "Determination method for total sulfur in coal" and GB / T 5447-2014 "Determination method for cohesiveness index of bituminous coal".

[0021] In the step (2), according to the dry basis coal blending ratios P1, P2, P3, P4, ..., P N , calculate the corrected proportion P of N single coals involved in coal blending N ', that is, P N '=(P N / (1-Mt N )) / (P1 / (1-Mt1)+P2 / (1-Mt2)+P3 / (1-Mt3)+P4 / (1-Mt4)………+P N / (1-Mt N )).

[0022] In the step (3), the corrected index of the blended coal in the coal blending scheme is calculated, i.e., Ad = ∑(Ad N ×P N ')÷∑P N '; Vdaf = ∑ (Vdaf N ×P N ')÷∑P N '; St.d = ∑(St.d N ×P N ')÷∑P N '; G = ∑ (G N ×P N ')÷∑P N '.

[0023] In step (4), if the corrected index of the blended coal satisfies Ad<Ad 设定 , Vdaf 设定1 <Vdaf<Vdaf 设定2 , St.d<St.d 设定 and G>G 设定 , then the N kinds of coal in the coal blending plan are adjusted according to the modified proportion P N 'Coal blending; if one or more of the corrected indicators of the blended coal do not meet Ad<Ad 设定 , Vdaf 设定1 <Vdaf<Vdaf 设定2 , St.d<St.d 设定 and G>G 设定 , then proceed to the next step.

[0024] In step (6), when CSR i <CSR 设定 When the corresponding coal blending plan is invalid; when CSR i ≥CSR 设定 When the corresponding coal blending scheme is used as an alternative, the next step is carried out, in which CSR i is the strength of coke after reaction, CSR 设定Set the value for the strength of coke after reaction.

[0025] In the step (6), firstly, N single types of coals involved in coal blending are collected and crushed to control the fineness of the coals to 74±3%, and then mixed according to the coal blending ratio of the coal blending scheme, and evenly mixed after three batch blending, and the moisture content is controlled at 10±1%. Then, the blended coal is loaded into a 40kg test coke oven for coking; 25kg of coke with a particle size greater than 25mm and less than 60mm produced by the 40kg test coke oven is taken in proportion, and then the post-reaction strength of the coke sample is tested in accordance with GB / T4000-2017 "Test Method for Reactivity and Post-Reaction Strength of Coke".

[0026] The time interval for correcting the proportion calibration of the coal blending scheme is 24 to 48 hours.

[0027] The correction ratio calibration of the coal blending scheme is to perform steps (1) to (8) on the coal blending scheme again.

[0028] Example 1

[0029] This embodiment provides a method for optimizing coal blending for stabilizing coke quality, and the method comprises the following steps:

[0030] Set Ad 设定 =9.8%, Vdaf 设定1 =24%, Vdaf 设定2 =26%, St.d 设定 =1.05%, G 设定 =80, CSR 设定 =68%.

[0031] The indicators of the 13 types of coal involved in coal blending before the adjustment of the coal blending plan are as follows:

[0032]

[0033]

[0034] S1: Regularly test the indicators of the 13 types of coal used in coal blending, as shown in the following table:

[0035]

[0036]

[0037] S2: In the coal blending plan, update the index of each single coal according to the test results of S1, and adjust the dry basis coal blending ratio P1, P2, P3, P4..., P N , calculate the corrected proportion P of N single coals involved in coal blending N ', that is, P N'=(P N / (1-Mt N )) / (P1 / (1-Mt1)+P2 / (1-Mt2)+P3 / (1-Mt3)+P4 / (1-Mt4)………+P N / (1-Mt N )).

[0038] Among them, the dry basis coal ratio P of the original coal blending scheme is 2# =3%, P 3# =10%, P 5# =6%, P 6# =3%, P 7# =10%, P 8# =13%, P 9# =3%, P 11# =12%, P 12# =9%, P 13# =4%, P 14# =12%, P 17# =7%, P 18# =8%;

[0039] Corrected proportions of 13 types of coal involved in coal blending 2# '=4%,P 3# '=11%,P 5# '=5%,

[0040] P 6# '=3%,P 7# '=9%,P 8# '=14%,P 9# '=3%,P 11# '=11%,P 12# '=8%,P 13# '=4%,

[0041] P 14# '=12%,P 17# '=7%,P 18# ' = 9%;

[0042] S3: Calculate the corrected index of the blended coal in the coal blending scheme, i.e. Ad = ∑(Ad N ×P N ')÷∑P N ';

[0043] Vdaf=∑(Vdaf N ×P N ')÷∑P N '; St.d = ∑(St.d N ×P N ')÷∑P N ';

[0044] G=∑(G N ×P N ')÷∑P N '.

[0045] Then Ad=9.68%, Vdaf=25.79%, St.d=0.94%; G=80.62.

[0046] S4: The corrected indicators of the blended coal meet Ad<9.8%, 24%<Vdaf<26%, St.d<1.05% and G>80. The 13 single coals in the blending scheme are adjusted according to the corrected proportion P N 'Coal blending.

[0047] Example 2

[0048] This embodiment provides a method for optimizing coal blending for stabilizing coke quality, and the method comprises the following steps:

[0049] Set Ad 设定 =9.8%, Vdaf 设定1 =24%, Vdaf 设定2 =26%, St.d 设定 =1.05%, G 设定 =80, CSR 设定 =68%.

[0050] The indicators of the 15 types of coal involved in coal blending before the adjustment of the coal blending plan are as follows:

[0051]

[0052] S1: Regularly test the indicators of 15 types of coal used in coal blending, as shown in the following table:

[0053]

[0054]

[0055] S2: In the coal blending plan, update the index of each single coal according to the test results of S1, and adjust the dry basis coal blending ratio P1, P2, P3, P4..., P N , calculate the corrected proportion P of N single coals involved in coal blending N ', that is, P N '=(P N / (1-Mt N )) / (P1 / (1-Mt1)+P2 / (1-Mt2)+P3 / (1-Mt3)+P4 / (1-Mt4)………+P N / (1-Mt N )).

[0056] Among them, the dry basis coal ratio P of the original coal blending scheme is 1# =6%, P 2# =5%, P 4# =9%, P 5# =4%, P 6# =11%,

[0057] P 7# =13%, P 8# =2%, P 9# =8%, P 10# =6%, P 11# =8%, P 12# =4%, P 13# =4%, P 14# =10%, P 16# =6%,

[0058] P 17# =4%;

[0059] Corrected proportion P of 15 types of coal involved in coal blending 1# '=6%,P 2# '=6%,P 4# '=11%,

[0060] P 5# '=4%,P 6# '=13%,P 7# '=11%,P 8# '=2%,P 9# '=6%,P 10# '=7%,P 11# '=10%,

[0061] P 12# '=3%,P 13# '=4%,P 14# '=8%,P 16# '=6%,P 17# ' = 3%;

[0062] S3: Calculate the corrected index of the blended coal in the coal blending scheme, i.e. Ad = ∑(Ad N ×P N ')÷∑P N ';

[0063] Vdaf=∑(Vdaf N ×P N ')÷∑P N '; St.d = ∑(St.d N ×P N ')÷∑P N ';

[0064] G=∑(G N ×P N ')÷∑P N '.

[0065] Then Ad=9.88%, Vdaf=26.13%, St.d=0.89%; G=81.92.

[0066] S4: The corrected indexes of the blended coal include Ad=9.88%, Vdaf=26.29%, which do not satisfy the range of Ad<9.8%, 24%<Vdaf<26%, and proceed to the next step.

[0067] S5: Re-formulate different coal blending plans, as shown in the following table:

[0068]

[0069] S6: Determine the coke strength after reaction CSR corresponding to each coal blending scheme i , when CSR i <CSR 设定 When the corresponding coal blending plan is invalid; when CSR i ≥CSR 设定 The corresponding coal blending scheme is used as an alternative scheme to proceed to the next step. First, collect N types of single coals involved in coal blending and crush them to control their fineness at 74±3%, and then mix them according to the coal blending ratio of the coal blending scheme. After three batches of blending, the mixture is evenly mixed, and the moisture is controlled at 10±1%. Then the blended coal is loaded into a 40kg test coke oven for coking. The method for determining the post-reaction strength of coke corresponding to each coal blending scheme is as follows: first prepare the coke sample, take 25kg of coke with a particle size larger than 25mm and smaller than 60mm from the coke produced by the 40kg test coke oven, and then mix them according to GB / T4000-2017

[0070] The "Test Method for Coke Reactivity and Post-Reaction Strength" tests the post-reaction strength of coke samples, as shown in the following table:

[0071]

[0072] Among them, CSR1=68.5%,CSR2=68.1%,CSR3=69.2%,all meet CSR i If the coal blending conditions are ≥68%, coal blending schemes 1, 2 and 3 are taken as alternatives and proceed to the next step.

[0073] S7: The corresponding coke reaction strength before the coal blending scheme is adjusted is used as the benchmark for optimizing the coal blending scheme, denoted as CSR 基 The sample preparation and testing were completed according to the S6 method, and the post-reaction strength CSR of the coke sample was measured.基 =69%.

[0074] S8: Coke strength after reaction CSR corresponding to each coal blending scheme i Benchmarking CSR 基 The ratio is recorded as B, that is, B = CSR i / CSR 基 , the ratio B value is large and the coke reaction strength CSR i Closer to the benchmark CSR 基 The coal blending scheme is taken as the preferred scheme. The ratio B of each coal blending scheme is as follows:

[0075] Coal blending solution Solution 1 Solution 2 Solution 3 Ratio B 0.993 0.987 1.003

[0076] The ratio B of Scheme 3 is 1.003, which is large and CSR3 is closer to the reference value of 69%. Scheme 3 is the preferred scheme.

[0077] The above description is only a small part of the implementation cases of the present invention, rather than all the implementation cases. Based on the implementation cases in the present invention, all other implementation cases obtained by ordinary technicians in this field without making any creative work are within the scope of protection of the present invention.

Claims

1. A method for optimizing coal blending for stabilizing coke quality, characterized in that The method comprises the following steps: (1) regularly testing the indicators of N types of coal involved in coal blending; (2) updating the indicators of each type of coal in the coal blending plan; (3) calculating the revised indicators of the blended coal in the coal blending plan; (4) deciding whether to proceed to the next step based on the revised indicators of the blended coal; (5) formulating different coal blending plans; (6) determining the coke reaction strength corresponding to each coal blending plan to decide whether to proceed to the next step; (7) using the corresponding coke reaction strength before the adjustment of the coal blending plan as the benchmark for optimizing the selection of the coal blending plan; (8) calculating the ratio of the coke reaction strength corresponding to each coal blending plan to the benchmark, and selecting the coal blending plan with the largest ratio as the preferred plan.

2. The method for optimizing coal blending for stabilizing coke quality according to claim 1, characterized in that: The blended coal in the coal blending scheme includes different combinations of lean coal, fat coal, 1 / 3 coking coal, coking coal, high-sulfur coking coal and gas coal.

3. The method for optimizing coal blending for stabilizing coke quality according to claim 1, characterized in that: In the step (1), the indexes of a single type of coal are tested in accordance with GB / T 212-2008 "Industrial analysis and determination methods for coal", GB / T 214-2007 "Determination method for total sulfur in coal" and GB / T 5447-2014 "Determination method for cohesiveness index of bituminous coal".

4. The method for optimizing coal blending for stabilizing coke quality according to claim 1, characterized in that: In the step (2), according to the dry basis coal blending ratios P1, P2, P3, P4, ..., P N , calculate the corrected proportion P of N single coals involved in coal blending N ', that is, P N '=(P N / (1-Mt N )) / (P1 / (1-Mt1)+P2 / (1-Mt2)+P3 / (1-Mt3)+P4 / (1-Mt4)………+P N / (1-Mt N )).

5. The method for optimizing coal blending for stabilizing coke quality according to claim 1, characterized in that: In the step (3), the corrected index of the blended coal in the coal blending scheme is calculated, i.e., Ad = ∑(Ad N ×P N ')÷∑P N '; Vdaf = ∑ (Vdaf N ×P N ')÷∑P N '; St.d = ∑(St.d N ×P N ')÷∑P N '; G = ∑ (G N ×P N ')÷∑P N '.

6. The method for optimizing coal blending for stabilizing coke quality according to claim 1, characterized in that: In step (4), if the corrected index of the blended coal satisfies Ad<Ad 设定 , Vdaf 设定1 <Vdaf<Vdaf 设定2 , St.d<St.d 设定 and G>G 设定 , then the N kinds of coal in the coal blending plan are adjusted according to the modified proportion P N 'Coal blending; if one or more of the corrected indicators of the blended coal do not meet Ad<Ad 设定 , Vdaf 设定1 <Vdaf<Vdaf 设定2 , St.d<St.d 设定 and G>G 设定 , then proceed to the next step.

7. A method for optimizing coal blending for stabilizing coke quality according to claim 1, characterized in that: In step (6), when CSR i <CSR 设定 When the corresponding coal blending plan is invalid; when CSR i ≥CSR 设定 When the corresponding coal blending scheme is used as an alternative, the next step is carried out, in which CSR i is the strength of coke after reaction, CSR 设定 Set the value for the strength of coke after reaction.

8. The method for optimizing coal blending for stabilizing coke quality according to claim 1, characterized in that: In the step (6), firstly, N single types of coals involved in coal blending are collected and crushed to control the fineness of the coals to 74±3%, and then mixed according to the coal blending ratio of the coal blending scheme, and evenly mixed after three batch blending, and the moisture content is controlled at 10±1%. Then, the blended coal is loaded into a 40kg test coke oven for coking; 25kg of coke with a particle size greater than 25mm and less than 60mm produced by the 40kg test coke oven is taken in proportion, and then the post-reaction strength of the coke sample is tested in accordance with GB / T4000-2017 "Test Method for Reactivity and Post-Reaction Strength of Coke".

9. A method for optimizing coal blending for stabilizing coke quality according to claim 1, characterized in that: The time interval for correcting the proportion calibration of the coal blending scheme is 24 to 48 hours.

10. The method for optimizing coal blending for stabilizing coke quality according to claim 1, characterized in that: The correction ratio calibration of the coal blending scheme is to perform steps (1) to (8) on the coal blending scheme again.

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