Mine coal gangue comprehensive utilization path evaluation method

Abstract

The invention discloses a mine coal gangue comprehensive utilization path evaluation method which comprises the following steps: step 1, carrying out performance determination on mine coal gangue to obtain gangue attribute characteristics of the coal gangue; investigating and analyzing the coal gangue utilization environment of the mine to obtain utilization environment characteristics of the coal gangue; investigating and analyzing a mine coal gangue utilization technology to obtain utilization technology characteristics of the coal gangue; carrying out economic investigation and analysis on coal gangue utilization of the mine to obtain economic benefit characteristics of the coal gangue; step 2, determining evaluation index weights of gangue attribute features, utilization of environmental features, utilization of technical features and economic benefit features, analyzing factors influencing comprehensive utilization of gangue according to the evaluation index weights, and extracting corresponding evaluation indexes; and 3, according to the evaluation indexes, constructing a coal gangue comprehensive utilization evaluation system. According to the evaluation method, the problem of how to determine a reasonable and efficient gangue utilization mode according to actual conditions of a mine is solved, and the utilization rate of the coal gangue of the mine is increased.

Description

Technical Field

[0001] The invention belongs to the technical field of coal resource utilization, and in particular relates to a method for evaluating a comprehensive utilization path of coal gangue in a mine. Background Art

[0002] In the process of large-scale production and utilization of coal resources in my country, a large amount of solid waste such as coal gangue will be generated. According to statistics, the cumulative stockpiling of coal gangue in my country currently exceeds 6 billion tons, forming more than 1,700 gangue mountains, covering an area of ​​more than 200,000 mu, and the emission volume is increasing year by year at about 500-800 million tons / a. The disposal and comprehensive utilization of coal gangue has become an urgent requirement of the coal industry and one of the important contents of sustainable development. As a special kind of mining solid waste, coal gangue itself is also a resource. Its rational and efficient comprehensive utilization will produce significant social and economic benefits. Classifying and utilizing coal gangue according to its resource attributes and maximizing its value is an important way to recycle coal gangue resources. The main utilization directions of existing coal gangue include: (1) Calorific value utilization: Coal gangue with a calorific value greater than 6272 kJ / kg can be directly used as boiler fuel. Coal gangue with a calorific value greater than 4180 kJ / kg is generally coal tunnel excavation gangue and washed gangue. Through simple washing and selection, low calorific value coal can be recovered using equipment such as cyclones or cyclones for use as boiler fuel.

[0003] (2) Extraction of valuable elements: Coal gangue usually contains some valuable elements, which can be extracted when the content reaches the required level. For example, sulfur in coal gangue mainly exists in the form of pyrite, and is in the form of nodules, lumps or other easily washed out forms. When its content reaches 6%, the pyrite can be recovered.

[0004] (3) Building materials: Coal gangue with chemical composition that meets the requirements and a calorific value of 2090~4180kJ / kg can be used to produce bricks, cement and other products. Coal gangue with a lower calorific value can be used as a cement admixture, concrete aggregate and other building materials.

[0005] (4) Chemical products: The development of coal gangue in the chemical industry can be used to extract kaolin and produce aluminum-containing chemical products (preparation of high-aluminum products, silicon-aluminum-iron alloys, preparation of 4A molecular sieves, etc.); (5) Agricultural ecology: Gangue contains rich organic matter and trace elements necessary for plant growth. It is also an ideal matrix and carrier for carrying nitrogen-fixing, phosphorus-dissolving, potassium-dissolving microorganisms. It can be used to produce fertilizers and make soil.

[0006] (6) Large-scale disposal: Coal gangue can also be utilized through large-scale disposal (mine filling, ground foundation, and land reclamation).

[0007] However, the types of mine gangue are different, the output varies, the chemical composition of coal gangue is complex, the utilization environment of gangue around the mine is different, the gangue utilization technology varies greatly, and the economic benefits of gangue utilization such as investment and cost are also different. The factors affecting the comprehensive utilization of coal gangue in mines are complex and changeable, which makes it difficult to choose the direction of coal gangue utilization in mines. How to determine a reasonable and efficient way of gangue utilization according to the actual conditions of the mine is a confusion faced by many coal enterprises. Therefore, it is necessary to provide a comprehensive utilization evaluation method of coal gangue that considers the influence of multiple factors. Summary of the invention

[0008] The purpose of the present invention is to provide a method for evaluating the comprehensive utilization path of coal gangue in mines, solve the problem of how to determine a reasonable and efficient gangue utilization method according to the actual conditions of the mine, and improve the utilization rate of coal gangue in mines.

[0009] The technical solution adopted by the present invention is a method for evaluating the comprehensive utilization path of coal gangue in a mine, comprising the following steps: Step 1: Conduct performance measurement on coal gangue in the mine to obtain the gangue property characteristics of the coal gangue; conduct research and analysis on the utilization environment of coal gangue in the mine to obtain the utilization environment characteristics of the coal gangue; conduct research and analysis on the utilization technology of coal gangue in the mine to obtain the utilization technology characteristics of the coal gangue; conduct research and analysis on the economic efficiency of coal gangue utilization in the mine to obtain the economic benefit characteristics of the coal gangue; Step 2: Determine the weights of evaluation indicators for gangue property characteristics, utilization environment characteristics, utilization technology characteristics, and economic benefit characteristics, analyze the factors affecting the comprehensive utilization of gangue according to the weights of evaluation indicators, and extract corresponding evaluation indicators; Step 3: Construct a comprehensive utilization evaluation system for coal gangue based on the evaluation indicators.

[0010] The present invention is also characterized in that: In step one, the performance of the mine gangue is measured to obtain the gangue property characteristics of the gangue. The specific process is: measuring the physical and chemical properties of the gangue to determine the resource attribute quality C1 of the gangue attribute B1; according to the output structure characteristics of the gangue, determine the production and sales capacity C2 of the gangue attribute B1.

[0011] In step one, the specific process of investigating and analyzing the environment for utilization of coal gangue to obtain the environmental characteristics of coal gangue utilization is as follows: investigating and analyzing the market environment for utilization of coal gangue, and determining the market environment C3 of utilization environment B2; investigating and analyzing the traffic environment for utilization of coal gangue, and determining the traffic environment C4 of utilization environment B2; investigating and analyzing the policy environment for utilization of coal gangue, and determining the policy environment C5 of utilization environment B2; investigating and analyzing the ecological environment for utilization of coal gangue, and determining the ecological environment C6 of utilization environment B2.

[0012] In step one, the specific process of investigating and analyzing the mine gangue utilization technology and obtaining the technical characteristics of the coal gangue utilization technology is as follows: investigating and analyzing the process conditions of the mine gangue utilization technology to determine the process maturity C7 of the utilization technology B3; investigating and analyzing the cost of the mine gangue utilization technology to determine the construction complexity C8 of the utilization technology B3; investigating and analyzing the risk conditions of the mine gangue utilization technology to determine the safety factor C9 of the utilization technology B3.

[0013] In step one, the economic investigation and analysis of mine gangue utilization is carried out to obtain the specific process of the economic benefit characteristics of coal gangue, which is: investigate and analyze the cost situation of mine gangue utilization technology to determine the disposal cost C10 of economic benefit B4; investigate and analyze the investment situation of mine gangue utilization technology to determine the investment amount C11 of economic benefit B4; investigate and analyze the income situation of mine gangue utilization technology to determine the income situation C12 of economic benefit B4; investigate and analyze the environmental benefit situation of mine gangue utilization technology to determine the environmental benefit C13 of economic benefit B4.

[0014] The specific process of determining the weights of evaluation indicators in step 2 is: coupling the analytic hierarchy process (AHP) with the entropy weight method, and finally obtaining the comprehensive weight value through combined weighting.

[0015] The analytic hierarchy process (AHP) was used to determine the subjective weights.

[0016] The entropy weight method is used to determine the objective weights.

[0017] The beneficial effects of the present invention are: The method for evaluating the comprehensive utilization path of coal gangue in mines provided by the present invention solves the problem of how to determine a reasonable and efficient gangue utilization method according to the actual conditions of the mine, maximizes the value of coal gangue, and improves the utilization rate of coal gangue in mines. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 It is a schematic diagram of the comprehensive utilization path evaluation method of coal gangue in mines according to the present invention. DETAILED DESCRIPTION

[0018] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] Example 1 The evaluation method for comprehensive utilization of coal gangue in mines proposed in this embodiment is as follows: Figure 1 As shown, the following steps are included: Step 1: Conduct performance measurement on coal gangue in the mine to obtain the gangue property characteristics of the coal gangue; conduct research and analysis on the utilization environment of coal gangue in the mine to obtain the utilization environment characteristics of the coal gangue; conduct research and analysis on the utilization technology of coal gangue in the mine to obtain the utilization technology characteristics of the coal gangue; conduct research and analysis on the economic efficiency of coal gangue utilization in the mine to obtain the economic benefit characteristics of the coal gangue; Step 2: Determine the weights of evaluation indicators for gangue property characteristics, utilization environment characteristics, utilization technology characteristics, and economic benefit characteristics, analyze the factors affecting the comprehensive utilization of gangue according to the weights of evaluation indicators, and extract corresponding evaluation indicators; Step 3: Construct a comprehensive utilization evaluation system for coal gangue based on the evaluation indicators.

[0020] Example 2 The evaluation method for comprehensive utilization of coal gangue in mines proposed in this embodiment is as follows: Figure 1 As shown, the following steps are included: Step 1: Conduct performance measurement on coal gangue in the mine to obtain the gangue property characteristics of the coal gangue; conduct research and analysis on the utilization environment of coal gangue in the mine to obtain the utilization environment characteristics of the coal gangue; conduct research and analysis on the utilization technology of coal gangue in the mine to obtain the utilization technology characteristics of the coal gangue; conduct research and analysis on the economic efficiency of coal gangue utilization in the mine to obtain the economic benefit characteristics of the coal gangue; In step 1, the performance of the coal gangue in the mine is measured to obtain the specific process of the gangue property characteristics of the coal gangue: the physical and chemical properties of the coal gangue are measured to determine the resource attribute quality C1 of the coal gangue attribute B1; according to the output structure characteristics of the coal gangue, the production and sales capacity C2 of the coal gangue attribute B1 is determined; Step 2: Determine the weights of evaluation indicators for gangue property characteristics, utilization environment characteristics, utilization technology characteristics, and economic benefit characteristics, analyze the factors affecting the comprehensive utilization of gangue according to the weights of evaluation indicators, and extract corresponding evaluation indicators; Step 3: Construct a comprehensive utilization evaluation system for coal gangue based on the evaluation indicators.

[0021] Example 3 The evaluation method for comprehensive utilization of coal gangue in mines proposed in this embodiment is as follows: Figure 1 As shown, the following steps are included: Step 1: Conduct performance measurement on coal gangue in the mine to obtain the gangue property characteristics of the coal gangue; conduct research and analysis on the utilization environment of coal gangue in the mine to obtain the utilization environment characteristics of the coal gangue; conduct research and analysis on the utilization technology of coal gangue in the mine to obtain the utilization technology characteristics of the coal gangue; conduct research and analysis on the economic efficiency of coal gangue utilization in the mine to obtain the economic benefit characteristics of the coal gangue; In step 1, the performance of the coal gangue in the mine is measured to obtain the specific process of the gangue property characteristics of the coal gangue: the physical and chemical properties of the coal gangue are measured to determine the resource attribute quality C1 of the coal gangue attribute B1; according to the output structure characteristics of the coal gangue, the production and sales capacity C2 of the coal gangue attribute B1 is determined; In step 1, the specific process of investigating and analyzing the utilization environment of coal gangue to obtain the utilization environment characteristics of coal gangue is as follows: investigating and analyzing the market environment for utilization of coal gangue, and determining the market environment C3 for utilization environment B2; investigating and analyzing the traffic environment for utilization of coal gangue, and determining the traffic environment C4 for utilization environment B2; investigating and analyzing the policy environment for utilization of coal gangue, and determining the policy environment C5 for utilization environment B2; investigating and analyzing the ecological environment for utilization of coal gangue, and determining the ecological environment C6 for utilization environment B2; Step 2: Determine the weights of evaluation indicators for gangue property characteristics, utilization environment characteristics, utilization technology characteristics, and economic benefit characteristics, analyze the factors affecting the comprehensive utilization of gangue according to the weights of evaluation indicators, and extract corresponding evaluation indicators; Step 3: Construct a comprehensive utilization evaluation system for coal gangue based on the evaluation indicators.

[0022] Example 4 The evaluation method for comprehensive utilization of coal gangue in mines proposed in this embodiment is as follows: Figure 1 As shown, the following steps are included: Step 1: Conduct performance measurement on coal gangue in the mine to obtain the gangue property characteristics of the coal gangue; conduct research and analysis on the utilization environment of coal gangue in the mine to obtain the utilization environment characteristics of the coal gangue; conduct research and analysis on the utilization technology of coal gangue in the mine to obtain the utilization technology characteristics of the coal gangue; conduct research and analysis on the economic efficiency of coal gangue utilization in the mine to obtain the economic benefit characteristics of the coal gangue; In step 1, the performance of the coal gangue in the mine is measured to obtain the specific process of the gangue property characteristics of the coal gangue: the physical and chemical properties of the coal gangue are measured to determine the resource attribute quality C1 of the coal gangue attribute B1; according to the output structure characteristics of the coal gangue, the production and sales capacity C2 of the coal gangue attribute B1 is determined; In step 1, the specific process of investigating and analyzing the utilization environment of coal gangue to obtain the utilization environment characteristics of coal gangue is as follows: investigating and analyzing the market environment for utilization of coal gangue, and determining the market environment C3 for utilization environment B2; investigating and analyzing the traffic environment for utilization of coal gangue, and determining the traffic environment C4 for utilization environment B2; investigating and analyzing the policy environment for utilization of coal gangue, and determining the policy environment C5 for utilization environment B2; investigating and analyzing the ecological environment for utilization of coal gangue, and determining the ecological environment C6 for utilization environment B2; The specific process of investigating and analyzing the utilization technology of coal gangue in step 1 to obtain the utilization technology characteristics of coal gangue is as follows: investigating and analyzing the process conditions of the utilization technology of coal gangue to determine the process maturity C7 of the utilization technology B3; investigating and analyzing the cost of the utilization technology of coal gangue to determine the construction complexity C8 of the utilization technology B3; investigating and analyzing the risk conditions of the utilization technology of coal gangue to determine the safety factor C9 of the utilization technology B3; In step 1, the economic investigation and analysis of coal gangue utilization in mines is carried out to obtain the specific process of the economic benefit characteristics of coal gangue: the cost situation of the mine gangue utilization technology is investigated and analyzed to determine the disposal cost C10 of the economic benefit B4; the investment situation of the mine gangue utilization technology is investigated and analyzed to determine the investment amount C11 of the economic benefit B4; the income situation of the mine gangue utilization technology is investigated and analyzed to determine the income situation C12 of the economic benefit B4; the environmental benefit situation of the mine gangue utilization technology is investigated and analyzed to determine the environmental benefit C13 of the economic benefit B4; Step 2: Determine the weights of evaluation indicators for gangue property characteristics, utilization environment characteristics, utilization technology characteristics, and economic benefit characteristics, analyze the factors affecting the comprehensive utilization of gangue according to the weights of evaluation indicators, and extract corresponding evaluation indicators; Step 3: Construct a comprehensive utilization evaluation system for coal gangue based on the evaluation indicators.

[0023] Example 5 The evaluation method for comprehensive utilization of coal gangue in mines proposed in this embodiment is as follows: Figure 1 As shown, the following steps are included: Step 1: Conduct performance measurement on coal gangue in the mine to obtain the gangue property characteristics of the coal gangue; conduct research and analysis on the utilization environment of coal gangue in the mine to obtain the utilization environment characteristics of the coal gangue; conduct research and analysis on the utilization technology of coal gangue in the mine to obtain the utilization technology characteristics of the coal gangue; conduct research and analysis on the economic efficiency of coal gangue utilization in the mine to obtain the economic benefit characteristics of the coal gangue; In step 1, the performance of the coal gangue in the mine is measured to obtain the specific process of the gangue property characteristics of the coal gangue: the physical and chemical properties of the coal gangue are measured to determine the resource attribute quality C1 of the coal gangue attribute B1; according to the output structure characteristics of the coal gangue, the production and sales capacity C2 of the coal gangue attribute B1 is determined; In step 1, the specific process of investigating and analyzing the utilization environment of coal gangue to obtain the utilization environment characteristics of coal gangue is as follows: investigating and analyzing the market environment for utilization of coal gangue, and determining the market environment C3 for utilization environment B2; investigating and analyzing the traffic environment for utilization of coal gangue, and determining the traffic environment C4 for utilization environment B2; investigating and analyzing the policy environment for utilization of coal gangue, and determining the policy environment C5 for utilization environment B2; investigating and analyzing the ecological environment for utilization of coal gangue, and determining the ecological environment C6 for utilization environment B2; The specific process of investigating and analyzing the utilization technology of coal gangue in step 1 to obtain the utilization technology characteristics of coal gangue is as follows: investigating and analyzing the process conditions of the utilization technology of coal gangue to determine the process maturity C7 of the utilization technology B3; investigating and analyzing the cost of the utilization technology of coal gangue to determine the construction complexity C8 of the utilization technology B3; investigating and analyzing the risk conditions of the utilization technology of coal gangue to determine the safety factor C9 of the utilization technology B3; In step 1, the economic investigation and analysis of coal gangue utilization in mines is carried out to obtain the specific process of the economic benefit characteristics of coal gangue: the cost situation of the mine gangue utilization technology is investigated and analyzed to determine the disposal cost C10 of the economic benefit B4; the investment situation of the mine gangue utilization technology is investigated and analyzed to determine the investment amount C11 of the economic benefit B4; the income situation of the mine gangue utilization technology is investigated and analyzed to determine the income situation C12 of the economic benefit B4; the environmental benefit situation of the mine gangue utilization technology is investigated and analyzed to determine the environmental benefit C13 of the economic benefit B4; Step 2: Determine the weights of evaluation indicators for gangue property characteristics, utilization environment characteristics, utilization technology characteristics, and economic benefit characteristics, analyze the factors affecting the comprehensive utilization of gangue according to the weights of evaluation indicators, and extract corresponding evaluation indicators; The specific process of determining the weight of the evaluation index in step 2 is: using the coupling of the hierarchical analysis method AHP and the entropy weight method, and finally obtaining the comprehensive weight value through combined weighting; The analytic hierarchy process (AHP) is used to determine the subjective weights; the entropy weight method is used to determine the objective weights; Step 3: Construct a comprehensive utilization evaluation system for coal gangue based on the evaluation indicators.

[0024] Example 6 The method for evaluating the comprehensive utilization path of coal gangue in mines proposed in this embodiment includes: (1) Construction of comprehensive utilization evaluation system of coal gangue; The establishment of an evaluation index system has a significant impact on the evaluation results. Constructing a scientific and reasonable multi-level evaluation index system for comprehensive utilization of coal gangue can provide a theoretical basis for determining the evaluation and selection model of the comprehensive utilization direction. Since the comprehensive utilization of coal gangue is affected by many conditions such as gangue properties, utilization environment, utilization technology and economic benefits, the actual conditions of the mine should be combined when making decisions on the utilization direction, and each utilization direction should be deeply analyzed and systematically studied. According to the "Guidelines for the Technical Utilization of Coal Gangue" and relevant policies and regulations on the comprehensive utilization of coal gangue, combined with the characteristics of the comprehensive utilization direction of coal gangue, the Delphi method is used to screen according to the principles of good representativeness, high sensitivity, scientific effectiveness, etc., and finally it is determined to evaluate from four aspects: gangue properties, utilization environment, utilization technology, and economic benefits, and 13 evaluation indicators are extracted, namely 1 primary condition, 4 secondary parameters, and 13 tertiary indicators. The evaluation system for comprehensive utilization of coal gangue is shown as follows. Figure 1 shown.

[0025] (2) Establishment of evaluation index weights; To build a complete evaluation index system, it is necessary to reasonably determine the weight of each index. The subjective weighting method (hierarchical analysis method AHP) and the objective weighting method (entropy weight method) are coupled, and the comprehensive weight value is finally obtained through combined weighting. ① The AHP method determines the subjective weight as follows: according to Figure 1 The AHP judgment matrix is ​​constructed based on the structural model. Experts in the industry are invited to score and assign values ​​to each indicator. The scoring standard is based on the 1-9 scale method created by TLSanty. According to the degree of influence and importance of each indicator, pairwise comparisons are made to construct a judgment matrix and ensure that the assignment is reasonable. Finally, the A-B judgment matrix of each factor of the target layer A and parameter layer B is constructed as shown in Table 1, and the judgment matrix of each factor of the parameter layer B and indicator layer C is shown in Tables 2 to 5. After the above judgment matrix is ​​established, calculations are performed, and consistency tests are performed on each judgment matrix. After calculation, the consistency ratio CR of all judgment matrices is less than 0.1, which meets the consistency requirements. The subjective weight value of each indicator is obtained through the above judgment matrix. See Table 6.

[0026] Table 1A-B Judgment Matrix

[0027] Table 2B1-C Judgment Matrix

[0028] Table 3B2-C Judgment Matrix

[0029] Table 4B3-C Judgment Matrix

[0030] Table 5B4-C Judgment Matrix

[0031] Table 6 Results of weights of indicators obtained by analytic hierarchy process

[0032] ② Entropy weight method is as follows: The entropy weight method is a commonly used method in objective weighting methods. It can calculate the entropy weight of each indicator according to the change range of the data and can better reflect the internal logic between the indicators. It specifically includes the following steps. Construct attribute matrix: Based on the collected research data, test data, etc., establish the classification standards of various indicators (see Table 7). According to the classification standards, invite experts to evaluate and score the indicator factors of each plan, with a full score of 100. Finally, the average of all experts' scores is the final score. Obtain the final score for each indicator .

[0033] Table 7 Index system and classification standards

[0034] Standardized attribute matrix: quantify the data of each indicator to between 0 and 1. All 13 indicators are quality indicators, that is, the larger the better. After the data is standardized, the normalized matrix V can be obtained as shown in the following formula: (1); (2); Where: ——No. i Plan No. j The score of each indicator; , ——the maximum and minimum values ​​of the same indicator; According to the normalized decision matrix V , calculate the entropy value of each indicator, See the following formula: (3); (4); Where: ——Indicators The proportion of m ——Number of solutions; Calculate the entropy weight corresponding to the indicator layer See the following formula: (5); Where: n ——Number of indicators.

[0035] ③ The AHP-entropy weight method is coupled to determine the comprehensive weight as follows: The weight results obtained by AHP method and entropy weight method are summarized as shown in the following formula. The subjective and objective weights and comprehensive weight table of each indicator are obtained: (6); Where: ——Comprehensive weight of the jth indicator; ——Decision preference coefficient, take 0.5; ——AHP subjective weight value.

[0036] (3) Construction of TOPSIS comprehensive evaluation model; After determining the weights of each indicator in the evaluation system, it is crucial to select an appropriate comprehensive evaluation method to select the optimal utilization direction. The TOPSIS method is a multi-objective decision-making method that can construct the optimal solution and the worst solution of the evaluation object (each indicator), and then calculate the relative fit of each solution to rank the solutions, so as to select the optimal solution. This model can objectively and truly reflect the gap between each solution and avoid the interference of subjective and objective factors. The specific steps are as follows.

[0037] ① Normalize the attribute matrix table to obtain the normalized decision matrix R as shown below: (7); (8); ② Perform weighted processing on the matrix R to obtain the weighted standard matrix K as shown below: (9); ③ Calculate and determine the positive ideal solution and negative ideal solution See the following formula: (10); (11); ④ Calculate the Euclidean distance of each solution to the optimal solution and the worst solution and , see the following formula: (12); (13); ⑤ Calculate the relative fit of each solution See the following formula, The closer it is to 1, the closer it is to the optimal level.

[0038] (14); According to the comprehensive evaluation results ,according to Sort each solution by its size. The bigger the better.

[0039] (4) Evaluation of coal gangue resource attributes; The evaluation of gangue resource attributes is carried out by testing and classifying the gangue resource attributes to obtain the gangue resource attribute parameters. According to the "Guidelines for the Technical Utilization of Gangue" GB / T 29163-2012 and other relevant technical specifications, the resource attribute indicators and resource attribute evaluation methods of the comprehensive utilization of gangue in different utilization paths are determined, the quality parameters and grades of the gangue resource attributes are obtained, and the feasibility path based on the gangue resource attributes is determined.

[0040] Resource attribute evaluation is to evaluate the suitability of coal gangue in a certain utilization direction based on the resource attribute value, using resource attribute quality indicators To measure the suitability level of its resource attributes, the relationship between the resource attribute suitability index and suitability level is shown in Table 8.

[0041] Table 8 Resource attribute suitability level judgment criteria

[0042] Resource attribute quality indicators are evaluated according to the influence of different utilization paths on the resource attributes of coal gangue. The resource attribute index of coal gangue is related to the resource attribute indicators that affect the utilization path, and for this purpose: (15); In the formula, For the i The first one selected in the utilization direction j Influencing parameter indicators, To influence the weight.

[0043] The resource attribute index of coal gangue is often determined by a single resource attribute index. When the resource attribute of coal gangue is determined by a single resource attribute index, there are: (16); ① Coal gangue power generation is as follows: According to 4.1 (Technical requirements for coal gangue as fuel) of the "Guidelines for the Technical Utilization of Coal Gangue" GB / T 29163-2012: The minimum calorific value of coal gangue used as fuel for circulating fluidized bed boilers should be greater than 6270 kJ / kg.

[0044] It is generally believed that when used for power generation, coal gangue with a calorific value greater than 6272 kJ / kg can be directly used as boiler fuel, and coal gangue with a calorific value greater than 4180 kJ / kg is generally coal tunnel excavation gangue and washed gangue. Through simple washing and the use of equipment such as cyclones or cyclones, low calorific value coal can be recovered for use as boiler fuel.

[0045] At present, the comprehensive utilization of coal gangue in my country is mainly selected according to the carbon content and calorific value. According to the carbon content and calorific value, coal gangue can be divided into four categories, as shown in Table 9. The calorific value of the fourth category of coal gangue is relatively high (calorific value 6270~12550kJ / kg), and it is generally suitable for use as a fuel for power generation. The third category of coal gangue (calorific value 2090~6270kJ / kg) can be used to produce cement, bricks and other building materials, and its partial calorific value is used in the preparation of building materials; the first and second category of coal gangue (calorific value below 2090kJ / kg) is difficult to use its calorific value, and can be used as a cement admixture, concrete aggregate and other raw materials for building materials, and can also be used to reclaim coal mining subsidence areas and backfill mine goaf areas.

[0046] Table 9 Carbon content classification

[0047] Based on the above analysis, the calorific value Qad is used as a single attribute indicator for coal gangue power generation. , then The greater the calorific value of coal gangue, the more conducive it is to power generation, and the greater the value of its resource attribute. Corresponding resource attribute indicators The values ​​are shown in Table 10.

[0048] Table 10 Gangue power generation index parameters and value standards

[0049] ②Recover pyrite as follows: According to 4.4.1 (Technical requirements for coal gangue for sulfur concentrate) of the "Guidelines for Technical Utilization of Coal Gangue" GB / T 29163-2012: The sulfur in coal gangue mainly exists in the form of pyrite, and when it is in the form of nodules, lumps or other easily washable forms, the pyrite can be recovered.

[0050] According to 4.1 of "Classification of Coal Gangue" GB / T 29162-2012, coal gangue can be divided into four categories according to total sulfur content, as shown in Table 11.

[0051] Table 11 Classification of coal gangue by total sulfur content

[0052] It is generally believed that sulfur concentrate can be recovered from coal gangue with a sulfur content of 6%. Comprehensive analysis shows that sulfur content is used as a single attribute indicator for recovering pyrite. , then The higher the sulfur content of coal gangue, the more conducive it is to recover pyrite, and the greater the value of its resource attribute. Corresponding resource attribute indicators The values ​​are shown in Table 12.

[0053] Table 12 Parameters and value standards for pyrite recovery from gangue

[0054] ③ Production of cement is as follows: According to the "Guidelines for the Technical Utilization of Coal Gangue" GB / T 29163-2012, the technical requirements for coal gangue used in cement are: the silica content of coal gangue used as raw materials for ordinary Portland cement should be greater than 35%, and the aluminum oxide content should be less than 25%. The loss on ignition, sulfur trioxide, volcanic ash test, and 28d compressive strength of cement mortar of over-fired or calcined coal gangue used in cement admixtures should meet the requirements of GB / T2847 (volcanic ash admixtures used in cement).

[0055] Coal gangue is an important raw material for cement. Its index requirements usually include the chemical composition, physical properties and other aspects of coal gangue. Its suitable chemical composition is shown in Table 13.

[0056] Table 13 Suitable chemical composition of cement produced from coal gangue

[0057] Based on the above analysis, the main indicators are selected as chemical components ω 1 is the SiO2 content, ω 2 is the Al2O3 content, and the corresponding index is extracted according to the mineral components and ; Corresponding resource attribute indicators The values ​​are shown in Table 14. The resource attribute index of cement produced from coal gangue is: (17); Table 14 Parameters and value standards for cement production from gangue

[0058] ④Brick making is as follows: According to the "Guidelines for the Technical Utilization of Coal Gangue" GB / T 29163-2012, the technical requirements for coal gangue used for sintered bricks are as follows: the main indicators of silica, alumina, radioactivity, etc. of coal gangue used for the production of sintered bricks should meet the requirements. The radioactivity of coal gangue used for sintered bricks should meet the requirements of GB6566 (Limits of Radioactive Nuclides in Building Materials), and the silica content is usually controlled at 55% to 70%, and the alumina content is usually controlled at 15% to 25%.

[0059] The quality of coal gangue bricks is related to the physical and chemical properties of coal gangue. Its suitable chemical composition is shown in Table 15.

[0060] Table 15 Suitable chemical composition of coal gangue bricks

[0061] Based on the above analysis, the main indicators are selected as chemical components ω 1 is the SiO2 content, ω 2 is the Al2O3 content, and the corresponding index is extracted according to the mineral components and ; Corresponding resource attribute indicators The values ​​are shown in Table 16. The resource attribute index of gangue brick making is: (18); Table 16 Parameters and value standards for gangue brick making

[0062] ⑥ Make lightweight aggregate as follows: Carbonaceous mudstone or mudstone gangue can be used as light aggregate. The property indicators of light aggregate made of gangue are mainly chemical components. ω 1 is the SiO2 content, ω 2 is the Al2O3 content, and the corresponding index is extracted according to the mineral components and ; Corresponding resource attribute indicators The values ​​are shown in Table 17. The resource attribute index of lightweight aggregate produced from coal gangue is: (19); Table 17 Parameters and value standards for gangue brick making

[0063] ⑦ Kaolin is as follows: The main property indicators of kaolin produced from coal gangue are chemical components. ω 1 is the kaolinite content, and the kaolinite content is used as a single attribute indicator for extracting kaolin , then The higher the kaolinite content of coal gangue, the more conducive it is to recover kaolin, and the greater the value of its resource attribute. Corresponding resource attribute indicators The values ​​are shown in Table 18.

[0064] Table 18 Parameters and value standards of kaolin extracted from gangue

[0065] ⑧ Aluminum-containing chemical products are as follows: The main property indicators of aluminum-containing chemical products produced from coal gangue are chemical components. ω 1 is the Al2O3 content, ω 1 As a single attribute indicator for extracting kaolin , then The higher the alumina content of coal gangue, the more conducive it is to the production of aluminum-containing chemical products, and the greater the value of its resource attribute. Corresponding resource attribute indicators The values ​​are shown in Table 19.

[0066] Table 19 Index parameters and value standards of aluminum-containing chemical products extracted from gangue

[0067] ⑨ Microbial fertilizers are as follows: The main property index of coal gangue as microbial fertilizer is ash yield ω 1. Extract the corresponding single attribute index according to the ash yield , then . Corresponding resource attribute indicators The values ​​are shown in Table 20.

[0068] Table 20 Index parameters and value standards for the production of microbial fertilizers from waste rock

[0069] ⑩ Prepare the soil as follows: The main property index of coal gangue soil is ash yield ω 1. Extract the corresponding single attribute index according to the ash yield , then . Corresponding resource attribute indicators The values ​​are shown in Table 21.

[0070] Table 21 Parameters and value standards of soil made from waste rock

[0071] ⑪The mine is filled as follows: The resource attribute index of coal gangue as underground filling material is mainly to meet environmental protection requirements, that is, the content of harmful elements in coal gangue does not exceed the standard. According to the content of harmful elements in coal gangue, the corresponding index is extracted. is the harmful element content, and the corresponding resource attribute index The values ​​are shown in Table 22.

[0072] Table 22 Parameters and value standards for waste rock filling

[0073] ⑫ Reclamation is as follows: The resource attribute index of coal gangue as land reclamation material is mainly to meet environmental protection requirements, that is, the content of harmful elements in coal gangue does not exceed the standard. According to the content of harmful elements in coal gangue, the corresponding index is extracted. is the harmful element content, and the corresponding resource attribute index The values ​​are shown in Table 23.

[0074] Table 23 Parameters and value standards for waste rock reclamation

[0075] ⑬ The foundation materials are as follows: The resource attribute indicators of coal gangue as foundation material mainly include gangue strength, etc. The corresponding indicators are extracted according to the uniaxial compressive strength of coal gangue , then . Corresponding resource attribute indicators The values ​​are shown in Table 24.

[0076] Table 24 Parameters and value standards for waste rock foundation construction

[0077] (5) Evaluation of output characteristics of comprehensive utilization of coal gangue; The evaluation of gangue output characteristics mainly evaluates the suitability of gangue in a certain utilization direction from the perspective of gangue output and gangue consumption in different directions, and uses the output structure suitability index to measure its suitability grade. The relationship between the output structure suitability index and the suitability grade is shown in Table 25.

[0078] Table 25 Output structure suitability level judgment criteria

[0079] The relationship between gangue generation and gangue disposal capacity is measured by the size of the residual rate of gangue after utilization in this direction. The smaller the residual rate, the higher the utilization rate of the generated gangue. If the residual rate is 0, it means full utilization. From the perspective of utilization efficiency, the suitability of this utilization direction is better. The values ​​of disposal capacity indicators are shown in Table 26.

[0080] (20); in, It is the output of coal gangue, calculated using the actual annual output or the average annual output. When coal gangue is classified, it is the output of a certain type of coal gangue, such as tunneling gangue output, mining gangue output or washed gangue output. It refers to the disposal capacity in a certain utilization direction, expressed by the actual annual processing volume or consumption. For example, in the filling direction, it is the annual consumption of filling gangue.

[0081] Table 26 Output structure indicator parameters and value standards

[0082] (6) Environmental assessment of comprehensive utilization of coal gangue; The regional environment that affects the comprehensive utilization of coal gangue mainly includes the market environment, traffic environment, policy environment, and ecological environment. The environmental suitability of coal gangue is comprehensively evaluated by the market environment, traffic environment, policy environment, and ecological environment of the preliminarily selected coal gangue utilization path, and the utilization environment suitability index is used to measure the suitability level of its utilization environment. The utilization environment suitability index and grade classification are shown in Table 27.

[0083] Table 27 Environmental quality suitability level judgment criteria

[0084] ① Market environment: The comprehensive utilization of coal gangue is affected by the market environment. Its suitability can be measured by the market demand of the utilization direction. Market demand refers to the degree of market unsaturation, which can be measured by the size of the remaining market demand. The market demand is divided into three levels: high, general, and low. The quality of the market environment can be obtained through investigation and survey, and the market demand is used as the first indicator to measure the utilization environment. The corresponding market environment suitability index values ​​are shown in Table 28.

[0085] Table 28 Market environment suitability level judgment criteria

[0086] ② Traffic environment: The comprehensive utilization of coal gangue is affected by the traffic environment. Its suitability can be measured by the traffic convenience of the utilization direction. The traffic convenience of comprehensive utilization of coal gangue is measured by the traffic distance between the mine and the comprehensive utilization project, and the traffic convenience is divided into three levels: high, general, and low. The market environment quality can be obtained through investigation and survey, and the traffic convenience is used as the second indicator to measure the utilization environment. The corresponding traffic environment suitability index values ​​are shown in Table 29.

[0087] Table 29 Traffic environment suitability level judgment criteria

[0088] ③ Policy environment: The comprehensive utilization of coal gangue is affected by the policy environment, and its suitability can be measured by the policy support for the utilization direction. The policy support for the comprehensive utilization of coal gangue is divided into high, general and low according to the national and local support for the comprehensive utilization of coal gangue. The quality of the policy environment can be obtained through investigation and survey, and the policy support is used as the third indicator to measure the utilization environment. The corresponding policy environment suitability index values ​​are shown in Table 30.

[0089] Table 30 Criteria for judging the suitability of the policy environment

[0090] ④ Ecological environment: The comprehensive utilization of coal gangue is affected by the ecological environment. Its suitability can be measured by the ecological friendliness of the utilization direction. Ecological friendliness refers to the impact of the comprehensive utilization direction of coal gangue on the ecological environment. It can be measured by ecological friendliness, which is divided into three levels: high, general, and low. Ecological friendliness is used as the fourth indicator to measure the utilization environment. The corresponding ecological environment suitability index values ​​are shown in Table 31.

[0091] Table 31 Ecological environment suitability level judgment criteria

[0092] (7) Economic evaluation of comprehensive utilization of coal gangue; Economic suitability evaluation is to evaluate the suitability of coal gangue from the economic situation of different utilization directions, and use the economic suitability index to measure its suitability level. The relationship between the economic suitability index and the suitability level is shown in Table 32.

[0093] Table 32 Economic suitability level judgment criteria

[0094] The economic evaluation of comprehensive utilization of coal gangue is a key factor in the comprehensive utilization of coal gangue. The economic suitability of coal gangue in different utilization directions is comprehensively evaluated by indicators such as disposal cost, investment amount, economic benefit, and environmental benefit.

[0095] ① Unit disposal cost: The unit disposal cost is used to evaluate its cost suitability, and the cost of comprehensive utilization of coal gangue is divided into three levels: high, medium and low. The cost of using a ton of coal is used as the first indicator to measure economic suitability. The corresponding unit disposal cost indicator values ​​are shown in Table 33.

[0096] Table 33 Unit disposal cost index level judgment standard

[0097] ② Investment amount: According to the investment amount in the direction of comprehensive utilization of coal gangue, the investment amount of comprehensive utilization of coal gangue is divided into three levels: high, medium and low. The investment amount of comprehensive utilization of coal gangue is used as the second indicator to measure economic suitability. The corresponding investment amount indicator values ​​are shown in Table 34.

[0098] Table 34 Investment Amount Index Level Judgment Criteria

[0099] ③ Economic benefits: According to the economic benefits of comprehensive utilization of coal gangue, the economic benefits of comprehensive utilization of coal gangue are divided into three levels: high, medium and low. The economic benefits of comprehensive utilization of coal gangue are used as the third indicator to measure economic suitability. The corresponding economic benefit index values ​​are shown in Table 35.

[0100] Table 35 Economic benefit index level judgment criteria

[0101] ④ Environmental benefits: According to the additional environmental benefits of comprehensive utilization of coal gangue, the environmental benefits of comprehensive utilization of coal gangue are divided into three levels: high, medium and low. The environmental benefits of comprehensive utilization of coal gangue are used as the fourth indicator to measure economic suitability. The corresponding environmental benefit index values ​​are shown in Table 36.

[0102] Table 36 Environmental benefit index level judgment criteria

Claims

1. A method for evaluating the comprehensive utilization path of coal gangue in mines, characterized in that: The following steps are involved: Step 1: measuring the performance of coal gangue in the mine to obtain the gangue property characteristics of the coal gangue; Investigate and analyze the utilization environment of coal gangue in mines to obtain the environmental characteristics of coal gangue utilization; Investigate and analyze the utilization technology of coal gangue in mines to obtain the technical characteristics of coal gangue utilization; Conduct economic research and analysis on the utilization of coal gangue in mines to obtain the economic benefit characteristics of coal gangue; Step 2: Determine the weights of evaluation indicators for gangue property characteristics, utilization environment characteristics, utilization technology characteristics, and economic benefit characteristics, analyze the factors affecting the comprehensive utilization of gangue according to the weights of evaluation indicators, and extract corresponding evaluation indicators; Step 3: Construct a comprehensive utilization evaluation system for coal gangue based on the evaluation indicators.

2. The method for evaluating the comprehensive utilization path of coal gangue in mines according to claim 1, characterized in that: The specific process of measuring the performance of mine gangue and obtaining the gangue property characteristics of the gangue as described in step one is: measuring the physical and chemical properties of the gangue to determine the resource attribute quality C1 of the gangue property B1; and determining the production and sales capacity C2 of the gangue property B1 based on the output structure characteristics of the gangue.

3. The method for evaluating the comprehensive utilization path of coal gangue in mines according to claim 1, characterized in that: The specific process of investigating and analyzing the environment for utilization of coal gangue in mines as described in step one to obtain the environmental characteristics for utilization of coal gangue is as follows: investigating and analyzing the market environment for utilization of coal gangue to determine the market environment C3 for utilization environment B2; investigating and analyzing the traffic environment for utilization of coal gangue to determine the traffic environment C4 for utilization environment B2; investigating and analyzing the policy environment for utilization of coal gangue to determine the policy environment C5 for utilization environment B2; investigating and analyzing the ecological environment for utilization of coal gangue to determine the ecological environment C6 for utilization environment B2.

4. The method for evaluating the comprehensive utilization path of coal gangue in mines according to claim 1, characterized in that: The specific process of investigating and analyzing the mine gangue utilization technology and obtaining the technical characteristics of coal gangue utilization described in step one is: investigating and analyzing the process conditions of mine gangue utilization technology to determine the process maturity C7 of utilization technology B3; investigating and analyzing the cost of mine gangue utilization technology to determine the construction complexity C8 of utilization technology B3; investigating and analyzing the risk conditions of mine gangue utilization technology to determine the safety factor C9 of utilization technology B3.

5. The method for evaluating the comprehensive utilization path of coal gangue in mines according to claim 1, characterized in that: The specific process of conducting an economic investigation and analysis on the utilization of coal gangue in mines in step one to obtain the economic benefit characteristics of coal gangue is as follows: conducting an investigation and analysis on the cost of the mine gangue utilization technology to determine the disposal cost C10 of the economic benefit B4; conducting an investigation and analysis on the investment situation of the mine gangue utilization technology to determine the investment amount C11 of the economic benefit B4; conducting an investigation and analysis on the revenue situation of the mine gangue utilization technology to determine the revenue situation C12 of the economic benefit B4; conducting an investigation and analysis on the environmental benefits of the mine gangue utilization technology to determine the environmental benefits C13 of the economic benefit B4.

6. The method for evaluating the comprehensive utilization path of coal gangue in mines according to claim 1, characterized in that: The specific process of determining the evaluation index weights in step 2 is: coupling the analytic hierarchy process (AHP) with the entropy weight method, and finally obtaining the comprehensive weight value through combined weighting.

7. The method for evaluating the comprehensive utilization path of coal gangue in mines according to claim 6, characterized in that: The analytic hierarchy process (AHP) is used to determine the subjective weights.

8. The method for evaluating the comprehensive utilization path of coal gangue in mines according to claim 6, characterized in that: The entropy weight method is used to determine the objective weights.

Images