Comprehensive assessment method for miscellaneous ores

Abstract

The invention relates to the technical field of mineral resources, in particular to a comprehensive assessment method for miscellaneous ores, which comprises the following steps: establishing a sinter cup test database, dynamically updating mineral powder variety and performance data, taking uniform samples of miscellaneous ores to be assessed with the weight not less than 500g, dividing into 3 parts, respectively detecting miscellaneous ore iron grade, harmful element mass content and impurity mass content for the 3 parts of samples, the iron grade score, the harmful element score and the impurity score of the corresponding sample are calculated, comprehensive evaluation calculation is carried out according to the formula that the comprehensive score = (A * T1) + (B * T2) + (C * T3), A is the iron grade score of the first sample, and T1 is the weight of the iron grade score; b is the score of the harmful element of the second sample, and T2 is the weight of the score of the harmful element; c is the impurity score of the third sample, and T3 is the weight of the impurity score; one-sided evaluation is avoided, the use demonstration period of some mineral powder is effectively shortened, the situation that the best purchase opportunity is missed due to uncertain factors such as the market and indexes is avoided, and the purchase cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of mineral resource technology, and in particular to a comprehensive evaluation method for miscellaneous minerals. Background Technology

[0002] With the rapid development of the steel industry and increasingly scarce resources, how to efficiently utilize various mineral resources, especially miscellaneous ores, has become crucial for steel companies to reduce costs and enhance competitiveness. Currently, the potential of miscellaneous ores remains untapped: In global iron ore resources, low-grade ore, high-impurity ore, and ore with high levels of harmful elements account for over 40%, but the utilization rate by domestic steel mills is generally low.

[0003] High-quality mixed ores typically offer a price advantage; however, they generally have higher levels of harmful elements and exhibit issues such as compositional variations, particle size distribution, and sintering performance. Direct use in sintering production may lead to decreased sinter quality and production efficiency, negatively impacting the stable operation of blast furnaces and reducing production costs. Traditionally, the use of new mixed ores involves determining the upper limit of their proportion using sintering cup tests (and industrial trials when necessary), before application in production. However, due to numerous uncertainties related to the market and performance indicators, using sintering cup tests to verify the usability of mixed ores is time-consuming and may result in missed optimal purchasing opportunities. Currently, there is a lack of comprehensive evaluation methods for mixed ores to quickly and effectively guide their application in actual production.

[0004] In existing technologies, new mineral powders are first tested in sintering cups after arriving at the factory, and industrial tests are conducted if necessary. Based on the test results, it is determined whether they can be used and the appropriate upper limit ratio. Then, they are purchased and consumed. This process is time-consuming and costly. Summary of the Invention

[0005] This invention provides a comprehensive evaluation method for miscellaneous minerals, which simultaneously covers the evaluation of grade, harmful elements, and impurities, avoiding one-sided evaluation. This invention effectively shortens the evaluation cycle for the use of some mineral powders, avoids missing the best purchase opportunity due to uncertainties such as market conditions and indicators, and reduces procurement costs.

[0006] To achieve the above objectives, the present invention employs the following technical solution: A comprehensive evaluation method for miscellaneous minerals includes the following steps: S1. Establish a sintering cup test database and dynamically update mineral powder types and performance data; S2. Take a uniform sample of the impurity mineral to be evaluated, weighing no less than 500 grams, and divide it into 3 portions; S3. Test the iron grade, harmful element content and impurity content of the three samples respectively, and calculate the iron grade score, harmful element score and impurity score of the corresponding samples. S4. Comprehensive evaluation calculation: Comprehensive score = (A×T1) + (B×T2) + (C×T3); Where A is the iron grade score of the first sample, and T1 is the weight of the iron grade score; B is the harmful element score of the second sample, and T2 is the weight of the harmful element score; C is the impurity score of the third sample, and T3 is the weight of the impurity score.

[0007] Furthermore, the mineral powder type and performance data include mineral powder type, chemical composition, particle size distribution, process parameters and indicators.

[0008] Furthermore, the specific calculation process for the iron grade score of the first sample is as follows: when the detected iron grade of the miscellaneous ore is greater than or equal to the set qualified standard, the iron grade score of the first sample is 100 points. When the detected iron grade of the mixed ore is less than the set qualification standard, the iron grade score of the first sample is calculated as (detected iron grade of mixed ore ÷ set qualification standard) × 100.

[0009] Furthermore, the specific calculation process for the hazardous element score of the second sample is as follows: the hazardous element load of the blast furnace after using the mixed ore is calculated based on the detected mass content of hazardous elements, and the safety limit of the hazardous element load of the blast furnace is set. When the load of all hazardous elements is less than or equal to the safety limit, the hazardous element score of the second sample is 100. When the load of all hazardous elements is greater than the safety limit, the score of a certain hazardous element in the second sample is calculated as [1 - (load of hazardous elements exceeding the standard - safety limit) ÷ safety limit] × 100. The hazardous element score for the second sample = the sum of all hazardous element scores / the number of hazardous element types.

[0010] Furthermore, the harmful elements include TiO2, S, K2O+Na2O and Zn.

[0011] Furthermore, the impurity score of the third sample is: Impurity score of the third sample = Total impurity score / Number of impurity types.

[0012] Furthermore, the impurities include SiO2 and Al2O3. The safe upper limit for the mass content of impurity Al2O3 is set at 2.5%. When the mass content of impurity Al2O3 is less than the safe upper limit, the impurity Al2O3 score is 100 points; when it exceeds the limit, the impurity Al2O3 score is [1 - (impurity Al2O3 - safe upper limit) ÷ safe upper limit] × 100. The safe range for the mass content of impurity SiO2 is set at 4.5% to 7%. When the mass content of impurity SiO2 is within the safe range, the score for impurity SiO2 is 100 points; when the mass content of impurity SiO2 exceeds the upper limit of the control range, 20 points are deducted for every 0.2% increase. When the mass content of impurity SiO2 is less than the lower limit of the control range, 20 points are deducted for every 0.2% decrease. Total impurity score: Al2O3 score × 50% + SiO2 score × 50%.

[0013] Compared with the prior art, the beneficial effects of the present invention are: 1) By establishing a sintering cup test database, the types and performance data of mineral powders are updated dynamically in a timely manner, forming a dynamic database that provides accurate data support for optimizing ore blending in sintering. 2) Comprehensive and objective: It covers the evaluation of quality, harmful elements, and impurities at the same time, avoiding one-sided evaluation; 3) By using a comprehensive evaluation method for miscellaneous ores, the sintering ore blend is optimized, and miscellaneous ores are gradually applied to the sintering ore blend. The blast furnace operating status is comprehensively evaluated to determine the appropriate upper limit ratio of miscellaneous ores. Then, based on the resources and cost-effectiveness of miscellaneous ores, the sintering ore blend is dynamically optimized. This evaluation method can effectively shorten the demonstration cycle for the use of some mineral powders, avoid missing the best purchasing opportunity due to uncertainties such as market conditions and indicators, and reduce procurement costs. 4) For mineral powders not recorded in the sintering cup test database, conduct a comprehensive evaluation, quickly provide usage suggestions, and provide technical support for optimizing ore blending; 5) This method can be used to rationally combine miscellaneous ores, eliminate the adverse effects of miscellaneous ores, and control the main indicators within the target range. Under the premise of ensuring the quality of sinter and the stable operation of the blast furnace, the cost of ore blending can be reduced. Detailed Implementation

[0014] The specific embodiments of the present invention will be further described below: This invention provides a comprehensive evaluation method for miscellaneous minerals, comprising the following steps: S1. Establish a sintering cup test database and dynamically update mineral powder varieties and performance data: Collect sintering test data and establish a sintering cup test database; the database will cover a wide range of mineral powder varieties; for each mineral powder, record its chemical composition, particle size distribution, process parameters and indicators in detail; update new mineral powder varieties and performance data in a timely and dynamic manner to make the sintering cup test database more comprehensive and accurate, and achieve better performance in data analysis and dynamic updates.

[0015] S2. Sample preparation: Take a uniform sample of the ore to be evaluated, weighing no less than 500 grams, and divide it into 3 portions.

[0016] S3. Test the iron grade, harmful element content and impurity content of the three samples respectively, and calculate the grade score, harmful element score and impurity score of the corresponding samples. Calculate the iron grade score A of the first sample: Set the qualified standard for the iron grade of the mixed ore. When the detected iron grade of the mixed ore is greater than or equal to the set qualified standard, the iron grade score of the first sample is 100 points. When the detected iron grade of the impurity ore is less than the set qualification standard, the iron grade score of the first sample = (detected iron grade of impurity ore ÷ set qualification standard) × 100; If the acceptable standard for the iron content of impurities in sintering iron ore powder is set to be 55% to 65%, and the detected iron content of impurities is 48%, then A = 48 ÷ 55 × 100 = 87 points.

[0017] Calculate the hazardous element score B of the second sample: Calculate the hazardous element load of the blast furnace after using the mixed ore based on the detected mass content of hazardous elements, and set the safety limit of the hazardous element load of the blast furnace. When the load of all hazardous elements is less than or equal to the safety limit, the hazardous element score of the second sample is 100. When the load of all hazardous elements is greater than the safety limit, the score of a certain hazardous element in the second sample is calculated as [1 - (load of hazardous elements exceeding the standard - safety limit) ÷ safety limit] × 100. The hazardous element score for the second sample = the sum of all hazardous element scores / the number of hazardous element types; The harmful elements include TiO2, S, K2O+Na2O, Zn, etc. The calculation is based on replacing 5% C ore powder with 5% B mixed ore: New blast furnace titanium load = (B mixed ore TiO2 - C ore powder TiO2) × replacement ratio × sintering iron-containing material unit consumption × sintering ore input consumption + original blast furnace titanium load. The safe limit for titanium load is ≤5kg / t, the safe limit for sulfur load is ≤6kg / t, the safe limit for alkali load is ≤3kg / t, and the safe limit for zinc load is ≤0.15kg / t. The actual mass content of titanium load is 7kg / t, B=[1-(7-5)÷5]×100=60 points; if it exceeds the standard by 2 times, 0 points are directly obtained; if it exceeds 2 times, a negative number is obtained, indicating that the harmful elements of the ore are seriously exceeded. When calculating the total score, the negative number obtained is used for statistics. Total score for harmful element load = Titanium load score × 25% + Sulfur load score × 25% + Alkali load score × 25% + Zinc load score × 25%; Calculate the impurity score C for the third sample: Impurities are the main components other than useful and harmful elements. Impurities include SiO2 and Al2O3. The safe upper limit for the mass content of impurity Al2O3 is set at 2.5%. When the mass content of impurity Al2O3 is less than the safe upper limit, the impurity Al2O3 score is 100 points; when it exceeds the limit, the impurity Al2O3 score = [1 - (Impurity Al2O3 - Safe Upper Limit) ÷ Safe Upper Limit] × 100; the actual impurity Al2O3 content is 3.5%, so the impurity Al2O3 score = [1 - (3.5 - 2.5) ÷ 2.5] × 100 = 60 points; when the impurity content is 5%, a score of 0 is directly obtained; when it is greater than 5%, a negative score is obtained, indicating that the impurities in the ore seriously exceed the standard, and the total score is calculated based on the actual negative score. The safe range for the mass content of impurity SiO2 is set at 4.5% to 7%. When the mass content of impurity SiO2 is within the safe range, the score for impurity SiO2 is 100 points. When the mass content of impurity SiO2 is greater than the upper limit of the control range, 20 points are deducted for every 0.2% increase, and so on. When it is equal to 8%, 0 points are awarded, and when it is greater than 8%, a negative number is awarded. When the mass content of impurity SiO2 is less than the lower limit of the control range, 20 points are deducted for every 0.2% decrease, and so on. When it is equal to 3.5%, 0 points are awarded, and when it is less than 3.5%, a negative number is awarded. Total impurity score: Al2O3 score × 50% + SiO2 score × 50%.

[0018] S4. Comprehensive evaluation calculation: Comprehensive score = (A×T1) + (B×T2) + (C×T3); Wherein, T1=40%, T2=35%, T3=25%, and A is the iron grade score of the first sample, and T1 is the weight of the grade score; B is the harmful element score of the second sample, and T2 is the weight of the harmful element score; C is the impurity score of the third sample, and T3 is the weight of the impurity score.

[0019] S5. Based on the overall score, the mineral powder is divided into 4 levels, with corresponding specific disposal recommendations: ①80-100 points is excellent: This grade of mineral powder has qualified grade, few harmful elements and low impurities. There is no need to do sintering cup test. It is recommended to purchase and use it directly based on the cost performance of the mineral powder at that time. ② A score of 60-79 indicates usability: It needs to be used in combination with other high-quality mineral powders to offset the adverse effects of the impure ore. If the impure ore has a high titanium dioxide content, it needs to be used in combination with other mineral powders with low titanium dioxide content. The processing cost is moderate, the risk is controllable, and sintering cup tests can be selectively performed. If the sintering cup test database shows mineral powders of the same type as the new impure ore, such as Indian powders of different grades, they need to be compared and analyzed with the same type of mineral powders in existing resources. If the new impure ore has a high cost-performance ratio and its quality is close to or even better than existing resources, sintering cup tests are not necessary, and it can be purchased and used according to the company's needs. If the quality of the new impure ore is inferior to existing resources, sintering cup tests must be performed first, and industrial tests must be conducted if necessary, to determine whether it can be used and its upper limit ratio before purchasing and using it.

[0020] ③ Use with caution if the content is 40-59: Subsequent processing costs are high, requiring impurity removal or harm reduction, such as increased sulfur content leading to higher desulfurization costs, or certain environmental risks. A professional assessment is needed to determine whether to use it. For new mixed ores, if other domestic steel companies have already used them, sintering cup tests are not necessary, but the change in harmful elements must be theoretically calculated. For example, if a certain mixed ore has a high TiO2 content, the blast furnace new titanium load after replacing it needs to be theoretically calculated. The calculation formula is: Blast furnace new titanium load = (mixed ore TiO2 - TiO2 to be replaced) × mixed ore replacement ratio × sintering iron-containing material consumption × sintering ore feed consumption + blast furnace original titanium load. If the new titanium load exceeds the steel company's control standard, the ratio needs to be adjusted downwards until it is within the control range. Simultaneously, compare with the usage of other companies to ensure that harmful elements are controlled within the steel company's standard range. Purchase and use can be carried out directly according to the company's needs. If there are no successful precedents for the application of new mixed ores in China, sintering cup tests should be conducted first, and industrial tests should be conducted if necessary to determine whether it can be used and the upper limit ratio before purchase and use. ④ A score of 0 to 39 indicates that the product is unusable: the grade is too low, harmful elements or impurities are seriously exceeded, it has no economic value and is risky, and it is recommended to keep it as a technical reserve for enterprises.

[0021] The following embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operation processes. However, the scope of protection of the present invention is not limited to the following embodiments. Unless otherwise specified, the methods used in the following embodiments are conventional methods.

[0022] Example

[0023] Taking a certain type of mixed ore as an example, the specific operation is as follows: 1. Take 500 grams of uniform sample and divide it into 3 portions for testing; 2. Itemized Results: Grade: Actual iron content 42.8%, qualified grade standard 55%. A=42.8÷55×100=77.8 points.

[0024] Harmful elements (converted to blast furnace harmful element load calculation): Titanium load 7.6 kg / t (safety limit 5 kg / t), titanium load score = [1 - (7.6 - 5) ÷ 5] × 100 = 48 points; Alkali load 3.8 kg / t (safety limit 3 kg / t), alkali load score = [1 - (3.8 - 3) ÷ 3] × 100 = 74 points; B = 48 × 25% + 74 × 25% + 25 + 25 = 80.5 points.

[0025] Impurities: Al2O3 content 14.3% (safe upper limit 2.5%), impurity Al2O3 score = [1 - (14.3 - 2.5) ÷ 2.5] × 100 = -372 points; SiO2 content 5.1% (safe range 4.5% - 7%), impurity SiO2 score 100 points.

[0026] C = -372 × 50% + 100 × 50% = -136 points 3. Overall score = (77.8 × 40%) + (80.5 × 35%) + (-136 × 25%) = 31.1 + 28 - 34 = 25.1 points; 4. Judgment result: Unusable. The grade is too low, the harmful elements are too high, and the content of impurity Al2O3 is seriously excessive. It has no economic value and is too risky. It is recommended to keep it as a technology reserve for enterprises.

Claims

1. A comprehensive evaluation method for miscellaneous minerals, characterized in that, Includes the following steps: S1. Establish a sintering cup test database and dynamically update mineral powder types and performance data; S2. Take a uniform sample of the impurity mineral to be evaluated, weighing no less than 500 grams, and divide it into 3 portions; S3. Detect the iron grade, harmful element content, and impurity content of the three samples respectively, and calculate the iron grade score, harmful element score, and impurity score of the corresponding samples. S4. Comprehensive evaluation calculation: Comprehensive score = (A×T1) + (B×T2) + (C×T3); Where A is the iron grade score of the first sample, and T1 is the weight of the iron grade score; B is the harmful element score of the second sample, and T2 is the weight of the harmful element score; C is the impurity score of the third sample, and T3 is the weight of the impurity score.

2. The comprehensive evaluation method for miscellaneous minerals according to claim 1, characterized in that, The mineral powder type and performance data include mineral powder type, chemical composition, particle size distribution, process parameters and indicators.

3. The comprehensive evaluation method for miscellaneous minerals according to claim 1, characterized in that, The specific calculation process for the iron grade score of the first sample is as follows: when the detected iron grade of the miscellaneous ore is greater than or equal to the set qualified standard, the iron grade score of the first sample is 100 points. When the detected iron grade of the mixed ore is less than the set qualification standard, the iron grade score of the first sample is calculated as (detected iron grade of mixed ore ÷ set qualification standard) × 100.

4. The comprehensive evaluation method for miscellaneous minerals according to claim 1, characterized in that, The specific calculation process for the hazardous element score of the second sample is as follows: the hazardous element load of the blast furnace after using the mixed ore is calculated based on the detected mass content of hazardous elements, and the safety limit of the hazardous element load of the blast furnace is set. When the load of all hazardous elements is less than or equal to the safety limit, the hazardous element score of the second sample is 100. When the load of all hazardous elements is greater than the safety limit, the score of a certain hazardous element in the second sample is calculated as [1 - (load of hazardous elements exceeding the standard - safety limit) ÷ safety limit] × 100. The hazardous element score for the second sample = the sum of all hazardous element scores / the number of hazardous element types.

5. The comprehensive evaluation method for miscellaneous minerals according to claim 4, characterized in that, The harmful elements include TiO2, S, K2O+Na2O and Zn.

6. The comprehensive evaluation method for miscellaneous minerals according to claim 1, characterized in that, The impurity score of the third sample is: Impurity score of the third sample = Total impurity score / Number of impurity types.

7. The comprehensive evaluation method for miscellaneous minerals according to claim 6, characterized in that, The impurities include SiO2 and Al2O3. The safe upper limit for the mass content of impurity Al2O3 is set at 2.5%. When the mass content of impurity Al2O3 is less than the safe upper limit, the impurity Al2O3 score is 100 points; when it exceeds the limit, the impurity Al2O3 score is [1 - (impurity Al2O3 - safe upper limit) ÷ safe upper limit] × 100. The safe range for the mass content of impurity SiO2 is set at 4.5% to 7%. When the mass content of impurity SiO2 is within the safe range, the score for impurity SiO2 is 100 points; when the mass content of impurity SiO2 exceeds the upper limit of the control range, 20 points are deducted for every 0.2% increase. When the mass content of impurity SiO2 is less than the lower limit of the control range, 20 points are deducted for every 0.2% decrease. Total impurity score: Al2O3 score × 50% + SiO2 score × 50%.