Method for establishing energy consumption-particle size distribution mathematical model in iron ore grinding process

Abstract

The invention discloses a method for establishing an energy consumption-particle size distribution mathematical model in an iron ore grinding process. According to the method, a research method combining experimental research and theoretical analysis is adopted. By taking iron ore as an example, an ore grinding test is carried out under different particle size conditions, and the association between the energy consumption and the ore particle size distribution in the ore grinding process is analyzed in detail. Through experimental data analysis, the following conclusions are obtained: under the same condition, the finer the ore particle size distribution is, the higher the ore grinding energy consumption is; on the contrary, the grinding energy consumption of the coarse-grained ore is relatively low. The inventor further establishes an energy consumption-particle size distribution mathematical model. An analysis result shows that the ore with the finer granularity needs to consume more energy in the crushing process so as to achieve the expected granularity refining degree. According to the method, practical guidance for controlling the ore grinding energy consumption based on the ore particle size distribution is provided for mine enterprises, and meanwhile, an important theoretical reference is provided for improving the energy efficiency in the ore grinding process.

Description

[Technical field]

[0001] The invention relates to the technical field of ore grinding, and in particular to a method for establishing an energy consumption-particle size distribution mathematical model in an iron ore grinding process. [Background technology]

[0002] Faced with a severe energy crisis, the mining industry is trying to achieve more environmentally friendly and economical production by improving the energy efficiency of the grinding process. Grinding process energy consumption is one of the important indicators for evaluating the performance of ore grinding process, but its potential relationship with ore particle size distribution has not received sufficient attention and in-depth research. Understanding this relationship not only fills the knowledge gap in this field in theory, but also has guiding significance for practical operations.

[0003] Ore grinding process and energy consumption issues:

[0004] 1. Overview of ore grinding process:

[0005] The ore grinding process is one of the key links in mining production. Its main task is to crush and grind the mined ore to the required fineness through mechanical force, so that the useful minerals in the subsequent mineral processing operations can be fully dissociated, and the mineral recovery rate and mineral processing indicators can be improved. The grinding process generally includes coarse grinding, medium grinding and fine grinding. The grinding fineness requirements of each stage are different, depending on the properties of the ore and the requirements of the mineral processing process.

[0006] The grinding process is usually carried out in equipment such as ball mills, rod mills, and autogenous mills. These equipments break the ore into finer particles through the impact and grinding of grinding media (such as steel balls, steel rods, or the ore itself) in the cylinder. In actual production, the grinding process not only requires a certain fineness, but also needs to consider factors such as energy consumption, grinding efficiency, and equipment wear. High efficiency and low consumption are one of the main goals pursued in the grinding process.

[0007] The energy consumption of the grinding process accounts for an important proportion of the entire ore processing process. The level of energy consumption directly affects the economic benefits and environmental impact of mining enterprises. The energy consumption of grinding mainly depends on the physical properties of the ore, the type of grinding equipment and operating parameters. The physical properties of the ore, such as hardness, toughness and particle size distribution, are important factors affecting the energy consumption of grinding. Ores with high hardness require more energy in the grinding process, and the particle size distribution directly affects the grinding efficiency and energy consumption.

[0008] In terms of grinding equipment, ball mill is one of the most widely used grinding equipment. Its main advantages are simple structure, easy operation and strong adaptability. However, the energy consumption of ball mill is relatively high, especially when processing fine-grained materials, the energy consumption problem is more prominent. Autogenous mill uses the impact and grinding effect of the ore itself to achieve grinding. Compared with ball mill, it can reduce the consumption of grinding media, but it is less efficient when processing ores with higher hardness. In order to improve grinding efficiency and reduce energy consumption, modern grinding technology is constantly developing. For example, the application of new equipment such as high-pressure roller mill and tower mill has significantly improved grinding efficiency and reduced energy consumption.

[0009] The operating parameters of the grinding process, such as the type and filling rate of the grinding media, grinding concentration, grinding time and grinding speed, will also have an important impact on energy consumption. For example, appropriately increasing the filling rate of the grinding media can improve the grinding efficiency, but too high a filling rate will increase the power consumption and wear of the equipment; controlling the appropriate grinding concentration can improve the grinding efficiency and reduce energy consumption, but too high a concentration will increase the slurry viscosity and affect the grinding effect.

[0010] The ore grinding process is a complex system engineering, and its energy consumption is affected by many factors. In actual production, it is necessary to comprehensively consider the physical properties of the ore, the selection of grinding equipment and the optimization of operating parameters to achieve the goal of high efficiency and low consumption. Through in-depth research on the relationship between ore particle size distribution and grinding energy consumption, it can provide a theoretical basis and practical guidance for the optimization of the grinding process and improve the economic benefits and resource utilization efficiency of mining enterprises.

[0011] 2. The role of energy consumption in the ore grinding process:

[0012] Energy consumption plays a vital role in the ore grinding process. It has a key economic and environmental impact on the entire mining industry. In the grinding process, energy consumption is not only the energy support necessary for the ore particles to achieve fineness, but also one of the core factors affecting grinding efficiency and cost. Understanding the specific mechanism of energy consumption in the grinding process is of great significance for improving ore processing efficiency and reducing costs.

[0013] The grinding process is to crush and grind the ore in the mill through external force, so as to achieve the purpose of mineral monomer dissociation. In this process, a large amount of mechanical energy needs to be converted into internal energy to break the internal structure of the ore and the bonding force between the crystal lattices. Energy consumption is mainly concentrated in two aspects: one is to overcome the compressive strength of the ore, which requires breaking the large block structure of the ore; the other is to overcome the interaction force between the fine particles of the ore to achieve further particle size reduction. Both processes require a lot of energy, which also explains why the grinding process has become a high-energy consumption link in mineral processing.

[0014] Grinding energy consumption is not only related to the use of electricity resources, but also directly linked to production costs. Higher energy consumption means more electricity consumption, which increases the operating costs of enterprises. Optimizing energy consumption in the ore grinding process has a direct impact on the profitability of mining companies. Grinding energy consumption may also affect the equipment life and maintenance costs of the mill. Excessive energy consumption may cause excessive wear of the equipment, thereby increasing the cost of equipment maintenance and replacement.

[0015] It can be seen that energy consumption plays multiple roles in the ore grinding process, which not only directly affects the grinding efficiency and enterprise costs, but is also related to environmental sustainability. Through in-depth analysis and understanding of the role of energy consumption, it will be possible to optimize the grinding process, improve grinding efficiency, reduce production costs, and achieve the sustainable development goals of mining companies. In actual operation, by accurately controlling the energy consumption input in the grinding process and using advanced grinding technology and equipment, the ore grinding efficiency can be effectively improved and energy consumption can be reduced, thereby achieving a win-win situation in economic and environmental benefits.

[0016] 3. Research status and current situation of ore grinding energy consumption

[0017] In recent years, the energy consumption in the ore grinding process has received widespread attention and has become one of the key research areas in the mining industry. Studies have shown that the grinding process accounts for a considerable proportion of the energy consumption in the entire ore processing process. How to effectively reduce the energy consumption in the grinding process will help save energy costs and improve the economic benefits of mining companies.

[0018] At present, the research is mainly focused on two directions: one is to optimize the grinding equipment and process flow to improve the grinding efficiency and thus reduce energy consumption; the other is to conduct in-depth research on the characteristics of the ore, especially the effect of the ore particle size distribution on the grinding energy consumption, to provide a scientific basis for formulating a more economical grinding strategy. Studying the relationship between ore particle size distribution and grinding energy consumption is of practical significance.

[0019] Domestic and foreign scholars have conducted a series of studies. Some of the studies have analyzed the energy consumption changes of ores with different particle size distributions during the grinding process through experiments, and found that the energy consumption of finer particle size ores is significantly higher than that of coarser particle size ores. These research results provide valuable data support for a deeper understanding of the energy consumption in the grinding process. At present, the theoretical model of the relationship between ore particle size distribution and energy consumption needs to be further improved.

[0020] Some studies have adopted advanced mathematical modeling methods to try to explain the energy consumption changes in the actual grinding process by establishing more accurate energy consumption prediction models. These models can explain the experimental phenomena to a certain extent, but they still need to be continuously verified and improved in practical applications to improve their applicability and accuracy.

[0021] Through the review of existing research results, it can be seen that the effect of ore particle size distribution on the energy consumption of the grinding process is a complex process with multiple factors and stages. Future research needs to combine experimental research with the optimization of theoretical models to further reveal its internal laws and provide more accurate guidance for energy saving in the ore grinding process. [Summary of the invention]

[0022] In view of the problem that the theoretical model of the relationship between ore particle size distribution and energy consumption in the current industry needs to be further improved, the present invention provides a method for establishing a mathematical model of energy consumption-particle size distribution in the iron ore grinding process. This application first focuses on the relationship between ore particle size distribution and energy consumption in the grinding process, takes iron ore as the research object, and examines in detail the changes in energy consumption in the grinding process under different particle size conditions through experiments. The results show that the particle size distribution of the ore plays a significant role in the energy consumption of the grinding process, and further mathematical models also reasonably explain this phenomenon. The results of this application not only help to improve the energy efficiency of the grinding process, but also provide mining companies with a method for reasonably controlling the energy consumption of the grinding process according to the particle size distribution of the ore.

[0023] The purpose of the present invention is achieved through the following technical solutions:

[0024] A method for establishing a mathematical model of energy consumption and particle size distribution in an iron ore grinding process comprises the following steps:

[0025] 1) Experimental materials and methods:

[0026] Iron ore was selected as the experimental raw material, which was obtained through mining by mining enterprises; iron ore samples with different particle size ranges were selected, including three levels of coarse particle size, medium particle size and fine particle size. The specific particle size distributions are:

[0027] coarse-grained samples (>3 mm), medium-grained samples (1-3 mm), and fine-grained samples (<1 mm);

[0028] Before grinding, the experimental samples were tested and analyzed for basic characteristics such as particle size distribution, mineral composition and mechanical properties to ensure the repeatability of the experimental operation and the reliability of the results;

[0029] The experiment used a ball mill for grinding test: the main parameters of the ball mill were set as follows: the cylinder diameter was 500mm, the cylinder length was 800mm, and the speed of the ball mill was 36rpm; the grinding media made of cast iron was selected, including grinding balls of different sizes, to ensure the grinding efficiency and stability of the results; during the grinding process, the feed amount and moisture content were kept consistent, the feed amount was set to 5kg, and the moisture content was set to 15%;

[0030] In the grinding experiment, iron ore samples of different particle sizes were ground for the same period of time (30 minutes, 60 minutes, and 90 minutes) by using the controlled variable method. During the experiment, the power consumption of the ball mill was monitored and its energy consumption data was recorded by a specific measuring device to ensure the accuracy and scientificity of the data.

[0031] In order to ensure the rigor of the experiment, the iron ore samples after grinding were subjected to the standard sieving method to determine the particle size distribution; a series of national standard sieves were used for sieving to measure the distribution ratio of different particle sizes; in order to avoid errors in the experiment, each grinding test was repeated three times, and the average value was taken as the final experimental data;

[0032] The experimental data were collated and analyzed by statistical software, mainly to investigate the energy consumption changes and their relationship in the interphase grinding process of iron ore with different particle sizes. By drawing a relationship diagram between energy consumption and particle size distribution, the difference in energy consumption required for iron ore samples with different particle sizes in the grinding process was further analyzed.

[0033] After completing the grinding test and analysis, the experimental results show that the iron ore samples with smaller particle sizes consume more energy during the grinding process, while the iron ore samples with larger particle sizes consume relatively less energy; this phenomenon can be explained by the energy input required for particle size refinement in the grinding mechanism, that is, the smaller the particle size, the larger the specific surface area per unit mass of the particle, and the higher the crushing energy required;

[0034] The selection of experimental materials, configuration of experimental equipment and design of experimental methods all followed strict scientific experimental standards to ensure the reliability and representativeness of the experimental results.

[0035] 2) Experimental results and analysis:

[0036] The experimental results show that the ore particle size distribution has a significant impact on the grinding energy consumption; in the grinding tests conducted under different particle size conditions, the energy consumption shows a regular trend of change with the change of ore particle size; specifically, the energy consumption of finer ore increases significantly during the grinding process, while the energy consumption of coarser ore is relatively low.

[0037] The results of the grinding tests under different particle sizes were statistically analyzed. The experiment showed that when the ore particle size distribution was fine, the particle size was below 100 microns, the grinding energy consumption increased significantly, and the average energy consumption reached a certain value. On the contrary, when the ore particle size was coarse, the particle size was above 1000 microns, the energy consumption decreased significantly, and the average energy consumption remained at a low level. Based on the experimental data, a general trend was obtained, that is, the finer the particle size, the higher the grinding energy consumption.

[0038] In further analyzing the relationship between energy consumption and particle size distribution, the experimental data were used to draw energy consumption graphs;

[0039] The analysis results show that the energy consumption curve presents a nonlinear growth trend. The experiment found that when the particle size distribution gradually becomes finer, the increase in grinding energy consumption gradually increases. This phenomenon can be explained by the energy demand of the ore during the crushing process. Fine-grained ores need to overcome greater cohesion and surface energy during the grinding process, thus consuming more energy.

[0040] The experimental results were explained theoretically by establishing a mathematical model of energy consumption-particle size distribution; the model verified the accuracy of the actual data and showed that the relationship between energy consumption and particle size distribution can be described by a certain mathematical formula; the mathematical model showed that there was a certain exponential relationship between grinding energy consumption (E) and particle size (D), that is, E∝D^n, where n is the parameter obtained by fitting the experimental data; by comparing the actual data with the model prediction values, it was found that the two had a good degree of agreement, which further proved the effectiveness of the model;

[0041] The experimental research and analysis results clearly pointed out that the ore particle size distribution has an important influence on the grinding energy consumption. Fine-grained ores consume more energy during the grinding process, while coarse-grained ores consume less energy. In order to achieve the goal of energy saving and consumption reduction, mining enterprises should adopt appropriate grinding processes and equipment according to the specific particle size distribution of the ore to minimize the grinding energy consumption while meeting production needs.

[0042] 3) Study on the influence of ore particle size distribution on grinding energy consumption:

[0043] The study quantitatively analyzed the relationship between particle size distribution and energy consumption through the grinding experiment of iron ore under different particle size conditions; the experimental results show that the finer the ore particle size, the more energy consumption is required for the grinding process; specifically, when the average particle size of the ore is reduced from 1000 microns to 100 microns, the required energy consumption increases by about 30%; through regression analysis, a mathematical model between particle size distribution and energy consumption is established, the model has a good fit, and the correlation coefficient reaches 0.92, indicating that the model can better predict and explain the impact of ore particle size distribution on energy consumption;

[0044] Analysis shows that finer-grained ores have greater crushing resistance during the grinding process, requiring more energy to achieve the desired crushing effect; in contrast, coarse-grained ores have relatively less crushing resistance and lower energy consumption; the increase in particle size refinement leads to a longer mill action time, indirectly increasing energy consumption;

[0045] The above experimental results and the establishment of mathematical models provide a scientific basis for understanding and predicting the impact of ore particle size distribution on grinding energy consumption; by optimizing the ore particle size distribution, the energy consumption in the grinding process can be effectively controlled, thereby improving the energy efficiency of mining production.

[0046] Furthermore, in step 1), the iron ore used in the experiment is typical in terms of chemical composition and mineral composition, and can well represent the common types of iron ore in industrial production.

[0047] Compared with the prior art, the present invention has the following advantages:

[0048] The present invention discloses a method for establishing a mathematical model of energy consumption-particle size distribution in the process of iron ore grinding. This application adopts a research method that combines experimental research with theoretical analysis. Taking iron ore as an example, we conducted grinding tests under different particle size conditions and analyzed in detail the relationship between energy consumption in the grinding process and the particle size distribution of the ore. After analyzing the experimental data, the following conclusions were drawn: Under the same conditions, the finer the particle size distribution of the ore, the higher the grinding energy consumption; conversely, the grinding energy consumption of coarse-grained ore is relatively low. In order to reasonably explain this phenomenon, we further established a mathematical model of energy consumption-particle size distribution. The analysis results show that ores with finer particle sizes need to consume more energy during the crushing process to achieve the expected degree of particle size refinement. This application not only provides practical guidance for mining enterprises to control grinding energy consumption based on ore particle size distribution, but also provides important theoretical references for improving the energy efficiency of the ore grinding process. [Specific implementation method]

[0049] The specific implementation modes of the present invention are further described below in conjunction with examples.

[0050] Example:

[0051] A method for establishing a mathematical model of energy consumption and particle size distribution in an iron ore grinding process comprises the following steps:

[0052] 1 Experimental materials and methods:

[0053] Iron ore was selected as the experimental raw material, which was obtained through mining by mining companies. The iron ore used in the experiment is typical in terms of chemical composition and mineral composition, and can well represent the common types of iron ore in industrial production. Iron ore samples with different particle size ranges were selected, including three levels of coarse particle size, medium particle size and fine particle size. The specific particle size distributions are: coarse particle samples (>3mm), medium particle size samples (1-3mm) and fine particle samples (<1mm). Before grinding, the experimental samples were tested and analyzed for basic characteristics such as particle size distribution, mineral composition and mechanical properties to ensure the repeatability of the experimental operation and the reliability of the results.

[0054] The experiment used a ball mill for grinding. The main parameters of the ball mill were set as follows: the cylinder diameter was 500 mm, the cylinder length was 800 mm, and the ball mill speed was 36 rpm. The grinding media made of cast iron, including grinding balls of different sizes, were selected to ensure the grinding efficiency and stability of the results. During the grinding process, the feed amount and moisture content were kept consistent, the feed amount was set to 5 kg, and the moisture content was set to 15%.

[0055] In the grinding experiment, iron ore samples of different particle sizes were ground for the same period of time (30 minutes, 60 minutes, and 90 minutes) by using the controlled variable method. During the experiment, the power consumption of the ball mill was monitored and its energy consumption data was recorded through a specific measuring device to ensure the accuracy and scientificity of the data.

[0056] In order to ensure the rigor of the experiment, the iron ore samples after grinding were subjected to the standard screening method to determine the particle size distribution. A series of national standard sieves were used for screening to measure the distribution ratio of different particle sizes. In order to avoid errors in the experiment, each grinding test was repeated three times, and the average value was taken as the final experimental data.

[0057] The experimental data were collated and analyzed by statistical software, mainly to investigate the energy consumption changes and their relationship in the interphase grinding process of iron ore with different particle sizes. By drawing a relationship diagram between energy consumption and particle size distribution, the difference in energy consumption required for iron ore samples with different particle sizes in the grinding process was further analyzed.

[0058] After completing the grinding test and analysis, the experimental results show that the iron ore samples with smaller particle sizes consume more energy during the grinding process, while the iron ore samples with larger particle sizes consume relatively less energy. This phenomenon can be explained by the energy input required for fine particle size in the grinding mechanism, that is, the smaller the particle size, the larger the specific surface area per unit mass of the particle, and the higher the crushing energy required. On this basis, the subsequent chapters will further establish an energy consumption-particle size distribution mathematical model to provide a theoretical explanation for the above experimental results.

[0059] The selection of the above experimental materials, configuration of the experimental equipment and design of the experimental methods all follow strict scientific experimental standards, ensuring the reliability and representativeness of the experimental results, and providing a solid foundation for the analysis of the experimental results and models in subsequent chapters.

[0060] 2 Experimental results and analysis:

[0061] The experimental results show that the ore particle size distribution has a significant impact on the grinding energy consumption. In the grinding tests conducted under different particle size conditions, the energy consumption shows a regular change trend with the change of ore particle size. Specifically, the energy consumption of finer ore increases significantly during the grinding process, while the energy consumption of coarser ore is relatively low.

[0062] The results of the grinding tests at different particle sizes were statistically analyzed. The experiment showed that when the ore particle size distribution is fine, for example, the particle size is below 100 microns, the grinding energy consumption increases significantly, and the average energy consumption reaches a certain value. On the contrary, when the ore particle size is coarse, for example, the particle size is above 1000 microns, the energy consumption decreases significantly, and the average energy consumption remains at a low level. Based on the experimental data, a general trend can be drawn, that is, the finer the particle size, the higher the grinding energy consumption.

[0063] When further analyzing the relationship between energy consumption and particle size distribution, the experimental data were used to draw an energy consumption curve. The analysis results show that the energy consumption curve shows a nonlinear growth trend. The experiment found that when the particle size distribution becomes finer, the increase in grinding energy consumption gradually increases. This phenomenon can be explained by the energy demand of the ore during the crushing process. Fine-grained ores need to overcome greater cohesion and surface energy during the grinding process, thus consuming more energy.

[0064] By establishing a mathematical model of energy consumption-particle size distribution, the experimental results are theoretically explained. The model verifies the accuracy of the actual data and shows that the relationship between energy consumption and particle size distribution can be described by a certain mathematical formula. The mathematical model shows that there is a certain exponential relationship between grinding energy consumption (E) and particle size (D), that is, E∝D^n, where n is the parameter obtained by fitting the experimental data. By comparing the actual data with the model prediction values, it can be found that the two have a good degree of consistency, which further proves the effectiveness of the model.

[0065] The experimental research and analysis results clearly pointed out that the ore particle size distribution has an important influence on the grinding energy consumption. Fine-grained ores consume more energy during the grinding process, while coarse-grained ores consume less energy. This discovery provides an important basis for how to optimize the ore grinding process and reduce energy consumption in actual production. In order to achieve the goal of energy saving and consumption reduction, mining companies should adopt appropriate grinding processes and equipment according to the specific particle size distribution of the ore, and minimize the grinding energy consumption while meeting production needs.

[0066] 3. Study on the influence of ore particle size distribution on grinding energy consumption:

[0067] The study quantitatively analyzed the relationship between particle size distribution and energy consumption by grinding iron ore under different particle size conditions. The experimental results show that the finer the ore particle size, the more energy consumption is required for the grinding process. Specifically, when the average particle size of the ore is reduced from 1000 microns to 100 microns, the required energy consumption increases by about 30%. Through regression analysis, a mathematical model between particle size distribution and energy consumption was established. The model has a good fit and a correlation coefficient of 0.92, indicating that the model can better predict and explain the impact of ore particle size distribution on energy consumption.

[0068] Analysis shows that finer-grained ores have greater crushing resistance during the grinding process and require more energy to achieve the desired crushing effect. In contrast, coarse-grained ores have relatively less crushing resistance and lower energy consumption. The increase in particle size refinement leads to a longer mill action time, which indirectly increases energy consumption.

[0069] The above experimental results and the establishment of mathematical models provide a scientific basis for understanding and predicting the impact of ore particle size distribution on grinding energy consumption. By optimizing the ore particle size distribution, the energy consumption in the grinding process can be effectively controlled, thereby improving the energy efficiency of mining production.

[0070] Finish:

[0071] In this application, we conducted an in-depth study on the relationship between ore particle size distribution and energy consumption during the grinding process and obtained some valuable results. We found that under the same other conditions, the finer the ore particle size distribution, the higher the grinding energy consumption. For coarse-grained ores, the grinding energy consumption is relatively low. This is mainly because finer ores require more energy to achieve the same degree of particle size refinement during the crushing process. Then, we reasonably explained this phenomenon by establishing an energy consumption-particle size distribution mathematical model. These research results not only help mining companies to reasonably control the energy consumption of the grinding process according to the particle size distribution of the ore, but also provide important theoretical references for improving the energy efficiency of the ore grinding process. Although this application has made some important discoveries, there are also some limitations. For example, although the energy consumption-particle size distribution mathematical model we established can better explain our experimental results, the scope of application and accuracy of the model need further research and verification. In addition, our research mainly takes iron ore as an example, and whether it is also applicable to other types of ores also requires further empirical research. In general, our study provides a new perspective and method for understanding and controlling the energy consumption of the grinding process. In future studies, we will further study and improve the energy consumption-particle size distribution model and try to apply it to more types of ores and grinding processes, so as to better serve the sustainable development of the mining industry.

[0072] References

[0073] [1] Ma Shaojian, Yang Jinlin, Shuai Zhichao, Zhu Pengyan, Li Hengjun, Deng Xingjian, Xu Wenzhe. Research on prediction of particle size distribution of cassiterite polymetallic sulfide ore grinding products[J]. Journal of China University of Mining and Technology, 2022, 51(03): 483-490.

[0074] [2] Tong Jiaqi, Fang Xin, Wu Zhiqiang, Liao Ningning, Xu Jindong, Wu Caibin. Grinding energy consumption and particle size distribution characteristics of hexagonal prisms as fine grinding media[J]. Nonferrous Metals Science and Engineering, 2019, 10(03): 86-91.

[0075] [3] Tu Yanan, Wang Lei, Mei Jiewen, Xu Zhiqiang. Effect of dry grinding on particle size distribution and stacking efficiency of long flame coal[J]. Coal Engineering, 2019, 51(03): 122-126.

[0076] [4] Wu Zhiqiang, Fang Xin, Tong Jiaqi, Liao Ningning, Xu Jindong, Wu Caibin. Grinding energy consumption and particle size distribution characteristics of nano-ceramic balls as fine grinding media[J]. Nonferrous Metals Science and Engineering, 2019, 10(05): 91-96.

[0077] [5] Lai Junquan, Liao Ningning, Fang Xin, Chen Xiaofeng, Yu Chao, Duan Anan, Wu Caibin. Particle size distribution model of ceramic ball mill products in vertical mill[J]. China Tungsten Industry, 2022, 37(05): 38-43.

[0078] The above description is a detailed description of the preferred feasible embodiments of the present invention, but the embodiments are not intended to limit the scope of the patent application of the present invention. All equivalent changes or modified changes completed under the technical spirit suggested by the present invention should fall within the patent scope covered by the present invention.

Claims

1. A method for establishing a mathematical model of energy consumption and particle size distribution in an iron ore grinding process, characterized in that: The steps include: 1) Experimental materials and methods: Iron ore was selected as the experimental raw material, which was obtained through mining by mining enterprises; iron ore samples with different particle size ranges were selected, including three levels of coarse particle size, medium particle size and fine particle size. The specific particle size distributions are: coarse-grained samples >3 mm), medium-grained samples 1-3 mm, and fine-grained samples <1 mm; Before grinding, the experimental samples were tested and analyzed for basic characteristics such as particle size distribution, mineral composition and mechanical properties to ensure the repeatability of the experimental operation and the reliability of the results; The experiment used a ball mill for grinding test: the main parameters of the ball mill were set as follows: the cylinder diameter was 500mm, the cylinder length was 800mm, and the speed of the ball mill was 36rpm; the grinding media made of cast iron was selected, including grinding balls of different sizes, to ensure the grinding efficiency and stability of the results; during the grinding process, the feed amount and moisture content were kept consistent, the feed amount was set to 5kg, and the moisture content was set to 15%; In the grinding experiment, the iron ore samples of different particle sizes were ground for the same time period of 30 minutes, 60 minutes and 90 minutes by using the controlled variable method. During the experiment, the power consumption of the ball mill was monitored and its energy consumption data was recorded by a specific measuring device to ensure the accuracy and scientificity of the data. In order to ensure the rigor of the experiment, the iron ore samples after grinding were subjected to the standard sieving method to determine the particle size distribution; a series of national standard sieves were used for sieving to measure the distribution ratio of different particle sizes; in order to avoid errors in the experiment, each grinding test was repeated three times, and the average value was taken as the final experimental data; The experimental data were collated and analyzed by statistical software to investigate the energy consumption changes and their relationship in the interphase grinding process of iron ores with different particle sizes. The energy consumption differences of iron ores with different particle sizes in the grinding process were further analyzed by drawing a relationship diagram between energy consumption and particle size distribution. After completing the grinding test and analysis, the results showed that the iron ore samples with smaller particle size consumed more energy during the grinding process, while the iron ore samples with larger particle size consumed relatively less energy; this phenomenon is explained by the energy input required for particle size refinement in the grinding mechanism, that is, the smaller the particle size, the larger the specific surface area per unit mass of the particle, and the higher the crushing energy required; The selection of experimental materials, configuration of experimental equipment and design of experimental methods all followed strict scientific experimental standards to ensure the reliability and representativeness of the experimental results. 2) Experimental results and analysis: The experimental results show that the ore particle size distribution has a significant impact on the grinding energy consumption; in the grinding tests conducted under different particle size conditions, the energy consumption shows a regular change trend with the change of ore particle size; Specifically, the energy consumption of finer ore during grinding increases significantly, while the energy consumption of coarser ore is relatively low. The results of the grinding tests under different particle sizes were statistically analyzed. The experiment showed that when the ore particle size distribution was fine, the particle size was below 100 microns, the grinding energy consumption increased significantly, and the average energy consumption reached a certain value. On the contrary, when the ore particle size was coarse, the particle size was above 1000 microns, the energy consumption decreased significantly, and the average energy consumption remained at a low level. Based on the experimental data, a general trend was obtained, that is, the finer the particle size, the higher the grinding energy consumption. In further analyzing the relationship between energy consumption and particle size distribution, the experimental data were used to draw energy consumption graphs; The analysis results show that the energy consumption curve presents a nonlinear growth trend. The experiment found that when the particle size distribution gradually becomes finer, the increase in grinding energy consumption gradually increases. This phenomenon is explained by the energy demand of the ore during the crushing process. Fine-grained ores need to overcome greater cohesion and surface energy during the grinding process, thus consuming more energy. The experimental results were explained theoretically by establishing a mathematical model of energy consumption-particle size distribution. The model verified the accuracy of the actual data and showed that the relationship between energy consumption and particle size distribution can be described by a certain mathematical formula. The mathematical model showed that there was a certain exponential relationship between grinding energy consumption E and particle size D, that is, E∝D^n, where n is the parameter obtained by fitting the experimental data. By comparing the actual data with the predicted values ​​of the model, it was found that the two had a good degree of agreement, which further proved the effectiveness of the model. The experimental research and analysis results clearly pointed out that the ore particle size distribution has an important influence on the grinding energy consumption. Fine-grained ores consume more energy during the grinding process, while coarse-grained ores consume less energy. In order to achieve the goal of energy saving and consumption reduction, mining enterprises should adopt appropriate grinding processes and equipment according to the specific particle size distribution of the ore to minimize the grinding energy consumption while meeting production needs. 3) Study on the influence of ore particle size distribution on grinding energy consumption: The study quantitatively analyzed the relationship between particle size distribution and energy consumption through the grinding experiment of iron ore under different particle size conditions; the experimental results show that the finer the ore particle size, the more energy consumption is required for the grinding process; specifically, when the average particle size of the ore is reduced from 1000 microns to 100 microns, the required energy consumption increases by about 30%; through regression analysis, a mathematical model between particle size distribution and energy consumption is established, the model has a good fit, and the correlation coefficient reaches 0.92, indicating that the model can better predict and explain the impact of ore particle size distribution on energy consumption; Analysis shows that finer-grained ores have greater crushing resistance during the grinding process and require more energy to achieve the desired crushing effect. In contrast, coarse-grained ores have relatively smaller crushing resistance and lower energy consumption. The increase in particle size refinement leads to a longer action time of the mill, which indirectly increases energy consumption.