Complex geological mine coal blending method

Abstract

A coal blending method for a complex geological mine belongs to the technical field of coal blending and comprises the following steps: establishing a working face coal quality database; acquiring a coal quality change rule; predicting coal quality and mining; according to the predicted mining coal quality, a coal blending strategy is selected, and the coal blending strategy is as follows: firstly blending, then washing coal and then blending coal, or firstly washing coal and then blending coal, so that the coal quality can be predicted in advance, different coal output working conditions can be pre-judged in advance, the coal blending processing sequence is adaptively adjusted according to the different coal output working conditions, the efficiency is improved, and the coal blending efficiency is improved. Through reasonable blending and washing treatment of high-quality, medium-quality and low-quality coal, the stable quality of a final coal product is guaranteed, the coal blending strategy can be adjusted in real time according to the change of a geological structure and market requirements, the coal quality difference of different working faces can be flexibly dealt with, and the grading and impurity removing functions of a mine type coal washing plant are achieved; and the additional value of the low-quality coal after washing is improved, so that the economic benefit is integrally improved.

Description

Technical Field

[0001] The invention relates to the technical field of coal blending, and in particular to a coal blending method for a mine with complex geology. Background Art

[0002] Coal blending specifically refers to the process of mixing two different types (or components) of raw coal in different proportions using a transfer device to form another type of coal with a different composition. The purpose of coal blending is usually to mix high-quality coal with relatively low-quality coal to improve the utilization efficiency of coal resources, reduce production costs, and improve the combustion performance and economic benefits of coal to meet the different requirements of different industries and users for coal quality and use.

[0003] There are two existing coal blending methods. One is to wash the coal first and then blend the coal after washing to meet different coal quality requirements. The other is to blend the coal first and then wash the coal after blending to improve washing efficiency, increase processing capacity and reduce coal washing costs.

[0004] Since the mine contains several mining areas, the geological differences between the mining areas are large, resulting in different coal qualities in each mining area. Even in the same mining area, as the mining work progresses, the quality of raw coal produced in the same mining area will vary greatly with the different mining locations. The existing coal blending processing sequence is fixed and single, and for the raw coal whose coal quality has been tested, it is impossible to predict different coal output conditions in advance, and to adaptively adjust the coal blending processing sequence according to different coal output conditions, which seriously affects the efficiency, economic benefits and stability of the overall work of washing and blending. Summary of the invention In order to solve the technical problems existing in the above-mentioned background technology that the existing coal blending processing sequence is fixed and single, and different coal discharge conditions cannot be predicted in advance, and the coal blending processing sequence cannot be adaptively adjusted according to different coal discharge conditions, which seriously affects the efficiency, economic benefits and stability of coal quality of the overall work of washing and blending, the present invention provides a coal blending method for complex geological mines.

[0005] The technical solution of the present invention is as follows: The present invention provides a method for blending coal in a mine with complex geology, comprising: Establish coal quality database for working face; Obtain the law of coal quality change; Predict coal quality and mine it; According to the predicted quality of the mined coal, a coal blending strategy is selected. The coal blending strategy is: blending first, then washing and blending, or washing first and then blending. The coal quality can be predicted in advance to predict different coal output conditions in advance, and the coal blending processing sequence can be adaptively adjusted according to different coal output conditions, thereby improving efficiency. Moreover, through the reasonable blending and washing of high, medium and low-quality coal, not only the quality of the final coal product is guaranteed to be stable, but the coal blending strategy can also be adjusted in real time according to changes in geological structure and market demand, and flexibly respond to the differences in coal quality of different working faces. Combined with the mine-type coal washing plant, its grading and impurity removal functions can be exerted to ensure that the low-quality coal increases its added value after washing, thereby improving the overall economic benefits.

[0006] Preferably, coal samples are collected regularly at the working face of each mining area, and chemical analysis of coal quality indicators is carried out. The coal quality at different working faces is determined based on the results of the chemical analysis and a database is established. Through the chemical analysis of coal samples, the actual situation of coal quality at each working face can be accurately understood, which provides an important basis for coal quality management, helps to formulate targeted coal quality improvement measures, optimize mining and processing processes, and thus improve the quality and market competitiveness of coal products.

[0007] Preferably, the coal quality data at different working faces in the database form time series data as they accumulate. The time series data are analyzed to find out the laws and trends of coal quality fluctuations. Reasonable mining plans can be formulated according to the coal quality conditions of different working faces, which helps to avoid over-mining at working faces with poor coal quality, while ensuring full mining at working faces with better coal quality, thereby improving the utilization efficiency of coal resources.

[0008] Preferably, the time series data analysis uses statistical methods and / or data mining technology to analyze the time series data and find out the laws and trends of coal quality fluctuations.

[0009] Preferably, the process of predicting coal quality is: based on database data and the law of coal quality change, a prediction model is used to predict the coal quality of the working face to be mined in each mining area, improve mining efficiency, assist in the selection of coal blending strategies, optimize resource utilization, and improve product quality.

[0010] Preferably, the coal blending strategy selection process is as follows: when there is a large difference in the coal quality of the two working faces, according to the washing capacity of the coal washing plant, two or three of the high, medium and low-quality coals are mixed according to the blending plan and then washed. This can effectively ensure the washing rate and improve economic benefits. After the mixed raw coal is washed, the coal blending ratio is determined and blended according to the calorific value requirements of downstream users to ensure that the product meets the requirements.

[0011] Preferably, when the difference in coal quality between the two working faces is small, the raw coal from different working faces is washed separately to achieve graded screening of different coal qualities, remove impurities and low-quality coal, and maximize the utilization rate and calorific value of the raw coal. After coal washing is completed, the coal blending ratio is determined and blended according to the calorific value requirements of downstream users to ensure that the product meets the requirements.

[0012] Preferably, under the premise that the calorific value requirements of downstream users are known, the coal blending heat formula is used to calculate the proportion of different components in the mixture so that the calorific value of the mixture reaches the target value. The coal blending heat formula is: h=x*h1+y*h2, h is the product calorific value requirement of the downstream user, x is the proportion of the first substance in the mixture, y is the proportion of the second substance in the mixture, h1 is the calorific value of the first substance, h2 is the calorific value of the second substance, and x+y=1.

[0013] It can be seen from the above technical solutions that the advantages of the present invention are: 1. Establish a database and analyze the laws of coal quality changes. According to the laws of coal quality changes, the coal quality can be predicted in advance, so as to predict different coal-out conditions in advance, and the coal blending processing sequence can be adaptively adjusted according to different coal-out conditions, thereby improving efficiency. Moreover, through the reasonable blending and washing of high, medium and low-quality coal, not only the quality of the final coal product is guaranteed to be stable, but the coal blending strategy can also be adjusted in real time according to changes in geological structure and market demand, and flexibly respond to the differences in coal quality of different working faces. Combined with the mine-type coal washing plant, its classification and impurity removal functions can be exerted to ensure that the low-quality coal is increased in added value after washing, thereby improving the overall economic benefits.

[0014] 2. Use the coal blending calorific value formula to calculate the proportion of different components in the mixture so that the calorific value of the mixture reaches the target value. While ensuring that the product meets the requirements, the minimum proportion of each component in the mixture that meets the conditions can be found according to demand to reduce costs. DETAILED DESCRIPTION

[0015] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solution of the present invention will be described clearly and completely below. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of them. Based on the embodiments in this patent, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this patent.

[0016] In a typical embodiment of the present invention, a method for blending coal in a mine with complex geology is proposed, and the specific process is as follows: 1. Establish a coal quality database for the working face.

[0017] Coal samples are collected regularly at the working faces of each mining area, and the collected coal samples are tested and analyzed for coal quality indicators such as ash content, volatile matter, sulfur content, calorific value, hardness, etc. The coal quality at different working faces is determined based on the results of the test and analysis, and a database is established. Through the test and analysis of coal samples, the actual situation of coal quality at each working face can be accurately understood, which provides an important basis for coal quality management, helps to formulate targeted coal quality improvement measures, optimize mining and processing processes, and thus improve the quality and market competitiveness of coal products.

[0018] 2. Obtain the law of coal quality changes.

[0019] As mining progresses and coal quality data from different working faces accumulate to form time series data, statistical methods and / or data mining techniques are used to conduct in-depth analysis of the coal quality index data (time series data) of the working faces to find out the laws and trends of coal quality fluctuations. For example, a coal quality variation function can be used to describe the variability of coal quality in coal seams, and the Kriging interpolation method can be used to derive a model of coal quality change laws.

[0020] Statistical methods are a scientific method to reveal the inherent laws and properties of data by collecting, organizing and analyzing data, including descriptive statistics and inferential statistics. Specific statistical techniques are divided into: correlation analysis, regression analysis, variance analysis, cluster analysis, discriminant analysis, principal component analysis and factor analysis; data mining technology is the process of extracting valuable information from large amounts of data. Its main purpose is to discover hidden patterns, laws and relationships from the data in order to make predictions, decisions and optimizations. Its main methods and techniques include data cleaning, data preprocessing, data visualization, data analysis, data model construction, data evaluation and optimization, etc. In specific applications, statistical methods and data mining techniques can be cross-linked, complementary and integrated.

[0021] 3. Predict coal quality and mine it.

[0022] Based on historical data (i.e. database data) and the laws of coal quality changes, time series prediction models, machine learning models and other prediction models are used to predict the coal quality of the working face to be mined in each mining area. The prediction results can provide timely and accurate information for coal mine production and coal selection, while reducing the number of subsequent coal sample collection and testing, improving work efficiency and reducing costs. According to the predicted coal quality, the coal mining sequence and coal mining quantity plan are customized. Specifically, according to the coal mining progress and coal quality changes of each working face, the coal mining sequence and coal mining quantity are dynamically adjusted, and the coal mining working faces are reasonably arranged to ensure the stability and selectivity of coal quality. For example, when the working faces to be mined contain low-quality coal working faces, it is possible to arrange to mine a low-quality coal working face and a high-quality coal working face at the same time to reduce coal quality fluctuations.

[0023] The establishment of a coal quality database and its coordination with efficient scheduling can not only carry out monthly and quarterly coal quality forecasts, but also, when geological structures and emergencies occur at various working faces, can timely and rationally blend and transport coal according to long-term fluctuation rules, thereby ensuring coal quality stability and selectivity and promoting overall economic benefits.

[0024] 4. Select the corresponding coal blending strategy based on the predicted coal quality.

[0025] There are two types of coal blending strategies: one is to mix the coal first, then wash the coal and then blend the coal; the other is to wash the coal first and then blend the coal.

[0026] Specifically, when there is a large difference in the quality of coal output from two working faces, a blending scheme of high, medium and low quality coal is determined according to the washing capacity of the coal washing plant, and two or three of the high, medium and low quality coals are mixed according to the blending scheme and then washed, which can effectively ensure the washing rate and improve economic benefits. After the mixed raw coal is washed, the coal blending ratio is determined according to the calorific value requirements of downstream users, and then the coal blending work of raw coal of different qualities is carried out according to the coal blending ratio to ensure that the product meets the requirements; When the difference in coal quality between two working faces is small, the raw coal from different working faces is washed separately to achieve graded screening of different coal qualities, remove impurities and low-quality coal, and maximize the utilization rate and calorific value of the raw coal. After coal washing is completed, the coal blending ratio is determined based on the calorific value requirements of downstream users, and then the coal blending of raw coal of different qualities is carried out according to the coal blending ratio to ensure that the product meets the requirements. For example, high-ash or low-calorific value coal is mixed with high-quality coal to reduce the discharge of ash, optimize the utilization rate of low-quality coal, avoid wasting high-quality coal resources, and maximize the economic benefits of the mine.

[0027] Through the rational blending and washing of high, medium and low quality coal, not only the quality of the final coal product is guaranteed to be stable, but the coal blending strategy can also be adjusted in real time according to changes in geological structure and market demand, and flexibly respond to the differences in coal quality in different working faces. Combined with the mine-type coal washing plant, its grading and impurity removal functions can be exerted to ensure that the low-quality coal is increased in added value after washing, thereby improving the overall economic benefits.

[0028] According to the product calorific value requirements of downstream users, the specific process of determining the coal blending ratio is as follows: Under the premise of knowing the calorific value demand data of downstream users, the coal blending heat formula is used to calculate the proportion of the mixture to determine the proportion of different components in the mixture so that the calorific value of the mixture reaches the target value. The coal blending heat formula is: h=x*h1+y*h2; Wherein, h is the product calorific value required by the downstream user (kcal / unit mass), x is the proportion of the first substance in the mixture, y is the proportion of the second substance in the mixture, h1 is the calorific value of the first substance (kcal / unit mass), and h2 is the calorific value of the second substance (kcal / unit mass).

[0029] Here, x+y = 1. Since h, h1, and h2 are all known, the integer ratio or simple fraction ratio of x and y can be calculated.

[0030] Example 1 When the calorific value of the washed mixed coal is 4200 kcal, the raw coal is 3000 kcal, and the calorific value of the product required by the power plant is above 3500 kcal: Let the proportion of washed mixed coal be x, the proportion of raw coal be y, and x+y=1 (because the two are mixed, the sum of their proportions is 1).

[0031] According to the coal heat formula: h=x*h 洗混煤 +y*h 原煤 ; Substitute the known data: 3500≤h=x*4200+y*3000; Since x+y=1, we can solve y=1-x, and substitute it into the above formula to get: 3500≤4200x+3000(1-x); 3500≤4200x+3000-3000x; 3500≤1200x+3000; 500≤1200x; 5 / 12≤x; y=1−x≤1-5 / 12=7 / 12; Since x and y are both ratios, and x+y=1, the minimum value of x is 5 / 12, and the corresponding maximum value of y is 7 / 12. Since the requirement is the minimum ratio that meets the calorific value of the power plant above 3500 kcal, x can take any value near 5 / 12, and the corresponding y is 1-x.

[0032] To simplify the calculation, x and y can be taken as integer ratios or simple fraction ratios, such as x=1 / 2, y=1 / 2. In this case, the calorific value after mixing is: h=1 / 2*4200+1 / 2*3000=3600 kcal, which meets the requirements of the power plant. At this time, x:y=1:1.

[0033] Example 2 When the calorific value of gangue is 200 kcal, the calorific value of washed mixed is 4200 kcal, and the calorific value of the product required by the power plant is above 3500 kcal: Assume that the proportion of washed mixed coal is x′, the proportion of gangue is y′, and x′+y′=1.

[0034] h=x′*h 洗混煤 +y′*h 矸石 ; Substitute the known data: 3500≤h=x′*4200+y′*200; Since x′+y′=1, we can get: 33 / 40≤x′; y′=1−x′≤1-33 / 40=47 / 40; Similarly, the minimum value of x' is 33 / 40, and the corresponding maximum value of y' is 7 / 40. To simplify the calculation, we can take x'=3 / 4, y'=1 / 4. At this time, the average calorific value after mixing is: h=3 / 4*4200+1 / 4*200=3200 kcal; It does not meet the requirements of the power plant (above 3500 kcal), so it is necessary to adjust the ratio of x' and y'. By continuous adjustment, the minimum ratio that meets the conditions is found. For example, x'=6 / 7, y'=1 / 7. At this time, the calorific value of the mixture is: h=6 / 7*4200+1 / 7*200=725400≈3628.57 kcal, which meets the requirements of the power plant. At this time, x:y=6:1.

[0035] It should be noted that the ratio in this embodiment is an approximate value, and the actual ratio may need to be fine-tuned according to specific circumstances, and no excessive restrictions are imposed here. The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for blending coal in a mine with complex geology, characterized in that: include: Establish coal quality database for working face; Obtain the law of coal quality change; Predict coal quality and mine it; According to the predicted quality of the mined coal, the coal blending strategy is selected. The coal blending strategy is: blend first, then wash the coal and then blend the coal, or wash the coal first and then blend the coal.

2. The method for blending coal in a complex geological mine according to claim 1, characterized in that: Coal samples are collected regularly at the working faces of each mining area, and coal quality indicators are tested and analyzed. The coal quality at different working faces is determined based on the test and analysis results and a database is established.

3. The method for blending coal in a complex geological mine according to claim 1, characterized in that: The coal quality data at different working faces in the database accumulate to form time series data. The time series data are analyzed to find out the laws and trends of coal quality fluctuations.

4. The method for blending coal in a complex geological mine according to claim 3, characterized in that: Time series data analysis uses statistical methods and / or data mining techniques.

5. The method for blending coal in a complex geological mine according to claim 1, characterized in that: The process of predicting coal quality is as follows: based on database data and the law of coal quality change, a prediction model is used to predict the coal quality of the working face to be mined in each mining area.

6. The method for blending coal in a complex geological mine according to claim 1, characterized in that: The coal blending strategy selection process is as follows: when there is a large difference in the coal quality of the two working faces, according to the washing capacity of the coal washing plant, two or three of the high, medium and low-quality coals are mixed according to the blending plan and then washed. After the mixed raw coal is washed, the coal blending ratio is determined and the coal is blended according to the calorific value requirements of downstream users.

7. The method for blending coal in a mine with complex geology according to claim 6, characterized in that: When the difference in coal quality between two working faces is small, the raw coal from different working faces is washed separately. After coal washing is completed, the coal blending ratio is determined and the coal is blended according to the calorific value requirements of downstream users.

8. The method for blending coal in a mine with complex geology according to claim 6 or 7, characterized in that: On the premise that the calorific value requirements of downstream users are known, the coal blending heat formula is used to calculate the proportion of different components in the mixture so that the calorific value of the mixture reaches the target value. The coal blending heat formula is: h=x*h1+y*h2, h is the product calorific value requirement of the downstream user, x is the proportion of the first substance in the mixture, y is the proportion of the second substance in the mixture, h1 is the calorific value of the first substance, h2 is the calorific value of the second substance, and x+y =1.