Method for evaluating quality of coking coal entering plant

Abstract

The present application provides a kind of coking coal quality evaluation method, comprising: determining target coking coal in each coking coal into plant, and target evaluation period of target coking coal in each evaluation period;Determine the quality standard of target coking coal in target evaluation period, the evaluation weight of single quality index, and the detection quality index of each batch of target coking coal in target evaluation period;Based on the detection quality index of each batch, determine the average value and standard deviation of detection quality index;Based on quality standard, average value and standard deviation, determine the exceeding limit value and exceeding coefficient of each detection quality index;According to quality standard, exceeding limit value and exceeding coefficient, determine the single exceeding percentage of each single quality index in detection quality index;Based on single exceeding percentage and single quality index evaluation weight, determine the total exceeding percentage for judging the quality of target coking coal into plant.The scheme quantifies the exceeding situation of coking coal, which is convenient for recording and judging the exceeding situation of each coking coal.

Description

Technical Field

[0001] This invention belongs to the field of metallurgy, and in particular relates to a method for evaluating the quality of coking coal entering the plant. Background Technology

[0002] Currently, there are many methods for evaluating the quality of coking coal, but most of them focus on the cost-effectiveness of coking coal, guiding under what conditions coking coal is cost-effective as a procurement reference. However, there are few methods for evaluating the quality of coking coal after procurement. Furthermore, evaluations of the fluctuations in quality indicators and the degree to which standards are exceeded by the coking coal delivered to the plant after procurement are even rarer.

[0003] In the actual procurement process of coking coal, there are certain differences between the quality of coking coal entering the plant and the quality standards. The test results of some batches differ significantly from the standard values, while the differences of some batches are small. Within an evaluation cycle, a large number of batches of certain varieties arrive. The quality fluctuations between different batches have not been evaluated, making it impossible to quantify the degree of exceeding the standards for different varieties upon entering the plant, and impossible to scientifically assess their stability. This is detrimental to the evaluation of coking coal, as well as to the quality control and procurement of coking coal. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a method for evaluating the quality of coking coal entering the plant, so as to solve the above problems.

[0005] To achieve the above and other related objectives, the present invention provides a method for evaluating the quality of coking coal entering the plant, comprising:

[0006] Among all the coking coal entering the plant, the target coking coal and the target evaluation period for the target coking coal in each evaluation cycle are determined;

[0007] Determine the quality standards, evaluation weights of individual quality indicators, and testing quality indicators for each batch of target coking coal within the target evaluation period.

[0008] Based on the aforementioned testing quality indicators for each batch, the average value and standard deviation of the testing quality indicators are determined;

[0009] Based on the aforementioned quality standards, average values, and standard deviations, the exceedance limits and exceedance coefficients for each of the aforementioned detection quality indicators are determined.

[0010] The percentage of each individual quality indicator exceeding the standard is determined based on the aforementioned quality standards, exceedance limits, and exceedance coefficients.

[0011] Based on the percentage of individual exceedances and the evaluation weight of individual quality indicators, the total percentage of exceedances used to judge the quality of target coking coal entering the plant is determined.

[0012] Optionally, determining the exceedance limit value for each of the aforementioned detection quality indicators includes:

[0013] If the quality standard is less than or equal to the standard value, then the limit value exceeding the standard is equal to the average value plus the standard deviation;

[0014] If the quality standard is greater than or equal to the standard value, then the limit value exceeding the standard is equal to the average value minus the standard deviation.

[0015] Optionally, determining the exceedance coefficient of each of the aforementioned detection quality indicators includes:

[0016] If the quality standard is less than or equal to the standard value, then the exceedance coefficient is 1;

[0017] If the quality standard is greater than or equal to the standard value, then the exceedance coefficient is -1.

[0018] Optionally, the percentage D of exceeding the standard for a single quality indicator is determined based on the quality standard, the exceedance limit value, and the exceedance coefficient, including:

[0019] If the exceeded limit value meets the quality standard, then D=0;

[0020] If the exceeded limit value does not meet the quality standard, then the formula for calculating D is as follows:

[0021]

[0022] in,

[0023] M represents the limit value exceeding the standard;

[0024] B represents the standard value of the quality standard;

[0025] K is the exceedance coefficient.

[0026] Optionally, based on the percentage of each individual exceedance and the evaluation weight of each individual quality indicator, the total percentage of exceedance used to judge the quality of the target coking coal entering the plant is determined, including:

[0027] Multiply the percentage of each item exceeding the standard by the corresponding evaluation weight of the quality indicator to obtain the individual evaluation value of the quality indicator.

[0028] The total percentage of exceeding the standard is obtained by summing the individual evaluation values ​​of each quality indicator.

[0029] Optionally, the quality indicators for testing include: ash content, volatile matter, sulfur content, caking index, clay layer thickness, and coal and rock standard deviation.

[0030] As described above, the coking coal quality evaluation method for incoming coal of the present invention has the following beneficial effects:

[0031] In this embodiment, a target coking coal and a target evaluation period for the target coking coal are selected. The exceedance of various quality standards of the target coking coal within the target evaluation period is calculated to obtain the percentage of each exceedance. Then, the total exceedance percentage is obtained based on the percentage of each exceedance. The quality evaluation of the target coking coal within the target evaluation period is determined by the total exceedance percentage. Attached Figure Description

[0032] Figure 1 This is a flowchart of the coking coal quality evaluation method in an embodiment of the present invention. Detailed Implementation

[0033] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0034] This application provides a method for evaluating the quality of coking coal entering the plant, which includes at least steps S100 to S150.

[0035] Step S100: Determine the target coking coal and the target evaluation period for the target coking coal in each evaluation cycle among the coking coals entering the plant.

[0036] Step S110: Determine the quality standards, evaluation weights of individual quality indicators, and testing quality indicators for each batch of target coking coal within the target evaluation period.

[0037] Step S120: Based on the test quality indicators of each batch, determine the average value and standard deviation of the test quality indicators;

[0038] Step S130: Based on the quality standard, average value, and standard deviation, determine the exceedance limit and exceedance coefficient of each of the detection quality indicators;

[0039] Step S140: Determine the percentage of each individual quality indicator exceeding the standard in the test quality indicators based on the quality standard, the limit value of exceeding the standard, and the coefficient of exceeding the standard;

[0040] Step S150: Based on the percentage of each item exceeding the standard and the evaluation weight of each quality indicator, determine the total percentage of the target coking coal entering the plant that exceeds the standard.

[0041] In this embodiment, a target coking coal and a target evaluation period for the target coking coal are selected. The exceedance of various quality standards of the target coking coal within the target evaluation period is calculated to obtain the percentage of each exceedance. Then, the total exceedance percentage is obtained based on the percentage of each exceedance. The quality evaluation of the target coking coal within the target evaluation period is determined by the total exceedance percentage.

[0042] It should also be noted that if some target coking coal in a certain batch is not tested and the quality indicators are not obtained within a cycle, then that batch will not be included in the calculation of the average value and standard deviation.

[0043] In an exemplary embodiment, the process of determining the exceedance limit value of each of the detection quality indicators includes at least steps S210 to S220.

[0044] Step S210: If the quality standard is less than or equal to the standard value, then the limit value exceeding the standard is equal to the average value plus the standard deviation;

[0045] Step S220: If the quality standard is greater than or equal to the standard value, then the limit value exceeding the standard is equal to the average value minus the standard deviation.

[0046] For example, if the standard value of the quality standard includes a preset low value and a preset high value, then the excess limit value includes an excess limit lower limit value and an excess limit upper limit value, wherein the excess limit lower limit value is equal to the average value minus the standard deviation, and the excess limit upper limit value is equal to the average value plus the standard deviation.

[0047] In this embodiment, the determination of the excess limit value is to facilitate obtaining the percentage of individual excess and the total percentage of excess.

[0048] In an exemplary embodiment, the process of determining the exceedance coefficient of each of the detection quality indicators includes at least steps S310 and S320.

[0049] Step S310: If the quality standard is less than or equal to the standard value, then the exceedance coefficient is 1;

[0050] Step S320: If the quality standard is greater than or equal to the standard value, then the excess coefficient is -1.

[0051] In this embodiment, the setting of the excess coefficient ensures that the subsequent calculation result of the excess percentage of a single item is a positive number.

[0052] In an exemplary embodiment, determining the percentage D of a single quality indicator exceeding the standard based on the quality standard, the exceedance limit value, and the exceedance coefficient includes:

[0053]

[0054] in,

[0055] M represents the limit value exceeding the standard;

[0056] B represents the standard value of the quality standard;

[0057] K is the exceedance coefficient.

[0058] In this embodiment, the percentage of each item exceeding the standard is calculated to determine the total percentage of exceeding the standard.

[0059] In an exemplary embodiment, the process of determining the total percentage of deviation from the target coking coal entering the plant based on the percentage of deviation from the target and the evaluation weight of the target quality index includes at least steps S410 to S420.

[0060] Step S410: Multiply the percentage of each item exceeding the standard by the corresponding evaluation weight of the quality indicator to obtain the individual evaluation value of the quality indicator.

[0061] Step S420: Add up the individual evaluation values ​​of each quality indicator to obtain the total percentage of exceeding the standard.

[0062] In this embodiment, the evaluation weight of each individual quality indicator is set separately for each detection quality indicator. The more important an individual detection quality indicator is, the higher the weight it is assigned.

[0063] In an exemplary embodiment, the quality indicators for detection include: ash content, volatile matter, sulfur content, caking index, clay layer thickness, and coal rock standard deviation S.

[0064] In this embodiment, the quality indicators considered include ash content (Ad), volatile matter (Vdaf), sulfur content (St.d), caking index (G), plastic layer thickness (Y), and coal-rock standard deviation (S). Ash content (Ad), volatile matter (Vdaf), sulfur content (St.d), caking index (G), plastic layer thickness (Y), and coal-rock standard deviation (S) are each individual quality indicators.

[0065] For example, the formula for calculating the average value X is shown below:

[0066]

[0067] Where i represents the lower bound of the batch and n represents the upper bound of the batch.

[0068] For example, the formula for calculating the standard deviation P is shown below:

[0069]

[0070] For example, coking coal includes No. 1 coking coal and No. 2 coking coal, with No. 1 coking coal selected as the target coking coal. A target evaluation period is selected, during which 8 batches of No. 1 coking coal arrive. The testing quality indicators of No. 1 coking coal are shown in Table 1, the quality standards of No. 1 coking coal are shown in Table 2, and the evaluation weights of each individual quality indicator of No. 1 coking coal are shown in Table 3.

[0071] Table 11 Statistical Table of Testing Quality Indicators for Coking Coal No. 11

[0072]

[0073] Table 21: Statistical Table of Quality Standards for Coking Coal

[0074]

[0075] Table 31: Statistical Table of Evaluation Weights for Individual Quality Indicators in Coking Coal No. 31

[0076]

[0077] 1. Based on Table 1, calculate the average value of each individual quality indicator. The calculation results are shown below:

[0078] X Ad = (9.76 + 9.89 + 10.04 + 9.94 + 9.43 + 10.02 + 9.71 + 10.16)% / 8 = 9.87%

[0079] Similarly, X Vdaf =20.90%, X St,d =0.52%, X G =72.8, X Y =13.5mm, X S =0.086.

[0080] 2. Based on the formula for calculating the standard deviation P, calculate the standard deviation of each test quality indicator. The calculation results are shown below:

[0081] P 2 Ad = (9.76-9.87) 2 + (9.89-9.87) 2 + (10.04 - 9.87) 2 + (9.94-9.87) 2 + (9.43-9.87) 2 + (10.02 - 9.87) 2 + (9.71-9.87) 2 + (10.16-9.87) 2 ) / (8-1)=0.053

[0082] Therefore, P Ad =0.23, similarly calculate P Vdaf =1.28, P St,d =0.05, P G =1.5, P Y =1.3, P S =0.0125.

[0083] 3. Determine the limit value for exceeding the standard.

[0084] The formula for calculating the excess limit value M is as follows:

[0085] If the quality standard is less than or equal to the standard value, then M = X + P;

[0086] If the quality standard is greater than or equal to the standard value, then M = XP;

[0087] If the standard value of the quality standard includes a preset low value and a preset high value, then the limit value of exceeding the standard includes a lower limit value and an upper limit value, wherein the lower limit value of exceeding the standard is M=XP, and the upper limit value of exceeding the standard is M=X+P.

[0088] Since the quality standard Ad for No. 1 coking coal is "≤10%", the limit value for exceeding Ad is M. Ad =X Ad +P Ad = (9.87 + 0.23)% = 10.10%.

[0089] Similarly, M can be calculated. St,d =0.57%, M S =0.0985.

[0090] Due to the V of No. 1 coking coal daf The quality standard is "20%-22%", which is a range, therefore

[0091] V daf The lower limit of the exceedance limit is M=X Vdaf -P Vdaf = (20.9 - 1.28)% = 19.62%;

[0092] V daf The upper limit of the exceedance limit is M=X Vdaf +P Vdaf = (20.9 + 1.28)% = 22.18%.

[0093] Since the quality standard for the caking index G of No. 1 coking coal is "≥75", therefore, M G =X G -P G =72.8 - 1.5 = 71.3; Similarly, M Y =X Y -P Y = (13.5-1.3)mm = 12.2mm.

[0094] 4. Determine the percentage of each item exceeding the standard.

[0095] Based on the formula for calculating the percentage D of a single item exceeding the standard, we can obtain the following:

[0096] Because the exceedance limit of quality indicator Ad for No. 1 coking coal (exceedance limit = 10.10%) is greater than the standard value of the quality standard (standard value = 10.0%), it indicates that this indicator has exceeded the standard. The percentage of exceedance for this single indicator in No. 1 coking coal is D. Ad =[(10.10%-10.0%) / 10.0%] 1 100% = 1%.

[0097] The exceedance limit of St,d in No. 1 coking coal (exceedance limit = 0.57%) is less than the standard value of the quality standard (standard value = 0.60%), therefore this indicates that the indicator has not exceeded the standard, that is, the percentage of exceedance of St,d in No. 1 coking coal is D. St,d The value is 0. Similarly, the percentage of coal petrographic standard deviation S exceeding the standard for No. 1 coking coal is D. S It is 0.

[0098] The exceedance limit of the G value of No. 1 coking coal (exceedance limit = 71.3) is less than the standard value of the quality standard (standard value = 75), therefore this indicates that the indicator exceeds the standard. The percentage of G value exceeding the standard for No. 1 coking coal is D. G =[(71.3-75) / 75] (-1) 100% = 4.98%; similarly, the percentage D of the Y value exceeding the standard for No. 1 coking coal can be calculated. Y =6.15%.

[0099] The lower limit of Vdaf exceeding the standard for No. 1 coking coal is 19.62% < 20% compared with the lower limit of the Vdaf quality standard of "20%-22%", indicating that the lower limit of Vdaf exceeding the standard does not meet the quality standard requirements.

[0100] Therefore, the percentage of Vdaf exceeding the standard for No. 1 coking coal = [(19.62% - 20.0%) / 20.0%] (-1) 100% = 1.9%

[0101] Meanwhile, the upper limit of Vdaf exceeding the standard is 22.18% > 22%, which means that the upper limit of Vdaf exceeding the standard does not meet the quality standard requirements.

[0102] Therefore, the percentage of Vdaf exceeding the standard in No. 1 coking coal = [(22.18% - 22.0%) / 22.0%] 1 100% = 0.82%, meaning the percentage of Vdaf exceeding the standard in No. 1 coking coal is 1.9% + 0.82% = 2.72%.

[0103] 5. Determine the total percentage of excessive levels in No. 1 coking coal.

[0104] C=DAd 30%+DVdaf 10%+DSt,d 30%+DG 10%+DY 10%+DS 10%

[0105] =1% 30% + 2.72% 10%+0 30% + 4.98% 10% + 6.15% 10%+0 10%

[0106] =1.686%

[0107] In summary, the total percentage of No. 1 coking coal exceeding the standard is 1.686%.

[0108] It should be noted that the lower the total percentage of exceeding the standard, the more stable the quality of the coking coal entering the plant; the higher the total percentage of exceeding the standard, the less stable the quality of the coking coal entering the plant.

[0109] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for evaluating the quality of coking coal entering the plant, characterized in that, include: Among all the coking coal entering the plant, the target coking coal and the target evaluation period for the target coking coal in each evaluation cycle are determined; Determine the quality standards, evaluation weights of individual quality indicators, and testing quality indicators for each batch of target coking coal within the target evaluation period. Based on the aforementioned testing quality indicators for each batch, the average value and standard deviation of the testing quality indicators are determined; Based on the aforementioned quality standards, average values, and standard deviations, the exceedance limits and exceedance coefficients for each of the aforementioned detection quality indicators are determined. The percentage of each individual quality indicator exceeding the standard is determined based on the aforementioned quality standards, exceedance limits, and exceedance coefficients. Based on the percentage of individual exceedances and the evaluation weight of individual quality indicators, the total percentage of exceedances used to judge the quality of target coking coal entering the plant is determined; The determination of the exceedance limit values ​​for each of the aforementioned detection quality indicators includes: If the quality standard is less than or equal to the standard value, then the limit value exceeding the standard is equal to the average value plus the standard deviation; If the quality standard is greater than or equal to the standard value, then the limit value exceeding the standard is equal to the average value minus the standard deviation; Determining the exceedance coefficient of each of the aforementioned detection quality indicators includes: If the quality standard is less than or equal to the standard value, then the exceedance coefficient is 1; If the quality standard is greater than or equal to the standard value, then the exceedance coefficient is -1.

2. The method for evaluating the quality of coking coal entering the plant according to claim 1, characterized in that, The percentage D of exceeding the standard for a single quality indicator is determined based on the aforementioned quality standards, exceedance limits, and exceedance coefficients, including: If the exceeded limit value meets the quality standard, then D=0; If the exceeded limit value does not meet the quality standard, then the formula for calculating D is as follows: in, M represents the limit value exceeding the standard; B represents the standard value of the quality standard; K is the exceedance coefficient.

3. The method for evaluating the quality of coking coal entering the plant according to claim 1, characterized in that, Based on the percentage of each out-of-specification item and the evaluation weight of each quality indicator, the total percentage of out-of-specification items used to judge the quality of the target coking coal entering the plant is determined, including: Multiply the percentage of each item exceeding the standard by the corresponding evaluation weight of the quality indicator to obtain the individual evaluation value of the quality indicator. The total percentage of exceeding the standard is obtained by summing the individual evaluation values ​​of each quality indicator.

4. The method for evaluating the quality of coking coal entering the plant according to claim 1, characterized in that, The quality indicators for testing include: ash content, volatile matter, sulfur content, bonding index, thickness of the plastic layer, and standard deviation of coal and rock.

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