A grinding mill system for cement grinding and a ball distribution method

Abstract

The application belongs to the field of ball mills, and particularly relates to a cement grinding mill system and a ball matching method. The cement grinding mill system comprises a control module, the control module comprises a device control unit, an instruction sending unit, a model construction unit and an information processing unit, the control module is used for controlling the device running state, sending control instructions, establishing a mathematical model for calculation, obtaining required friction coefficients and other related parameters, and guiding the ball mill ball matching of a cement enterprise in actual production. The ball matching method can significantly improve the grinding efficiency of the ball mill, make the operation of the ball mill more stable, reduce unnecessary energy consumption, reduce the wear of the lining plate in the ball mill, reduce the frequency of maintenance and replacement, realize the automatic operation and optimized control of the cement ball mill by adopting intelligent control technology, and improve the production efficiency.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of ball mills, in particular to a cement grinding mill system and a ball arrangement method. BACKGROUND

[0002] The steel ball arrangement of a cement ball mill is determined according to factors such as the particle size, hardness and fineness of the material to be ground. Generally speaking, the larger the particle size of the material to be ground, the larger the steel ball gradation. Meanwhile, if the hardness or fineness of the material changes, the steel ball gradation also needs to be adjusted, and the existing ball arrangement method still has some problems.

[0003] Firstly, because the number of balls is inversely proportional to the cube of the diameter of the balls, if the ball diameter is too large, the number of balls per unit load will decrease, the impact frequency will decrease, the void ratio between the steel balls will increase, the material flow rate will be too fast, coarse particles are likely to be generated, and the wear rate and impact rate of the mill liner will increase, and the liner bolts are likely to be damaged;

[0004] Different cement enterprises use different types and properties of materials and different processes, and it is difficult to set a matching ball arrangement, which needs to be constantly explored according to the actual situation, thereby increasing unnecessary energy consumption and production cost, and the wear of the mill liner inside the ball mill is more serious, and the service life is shorter. SUMMARY

[0005] In order to solve the problem that it is difficult to set a matching ball arrangement, which needs to be constantly explored according to the actual situation, thereby increasing unnecessary energy consumption and production cost, the application provides a cement grinding mill system and a ball arrangement method.

[0006] The cement grinding mill system and the ball arrangement method provided by the application adopt the following technical scheme:

[0007] A cement grinding mill system comprises:

[0008] A control module comprises a device control unit, an instruction sending unit, a model building unit and an information processing unit, the control module is used for controlling the device running state, sending control instructions, establishing a mathematical model for calculation to obtain the required friction coefficient and other related parameters, thereby guiding the ball mill ball arrangement of the cement enterprise in actual production;

[0009] An information input module comprises a device information input unit, a material information input unit and a running information input unit, the information input module is connected with the control module, and the information input module is used for inputting the specifications and models of the ball mill to select suitable ball diameters and ball weights, and inputting the physical properties and chemical properties of the material to cooperate with the calculation of the mathematical model;

[0010] The data acquisition module includes a material acquisition unit, a device rotation speed acquisition unit, a weight acquisition unit and an information processing unit, is connected with the control module, is used for collecting the grinding data of the material, collecting the running speed of the device and the data of the weight borne by the device, and sending and storing the collected data;

[0011] The calculation module is connected with the control module, is used for calculating the friction coefficient between the ball and the ball mill liner according to the collected material data, calculating the collision breaking force between the ball and the material and the impact breaking force between the ball and the material, and providing data support for the ratio of the steel balls according to the relationship among the friction coefficient between the ball and the liner, the collision breaking force between the ball and the material and the impact breaking force between the ball and the material;

[0012] The steel ball ratio module is connected with the control module and the calculation module, adjusts and optimizes the ball ratio scheme according to the data generated during the operation of the device, reasonably matches the steel balls of different specifications, considers the grinding efficiency and the wear rate of the mill liner, selects the appropriate ball diameter according to the actual situation, avoids too large or too small, and maintains the appropriate impact times and material flow rate;

[0013] The scheduling module is connected with the control module and the steel ball ratio module, is used for scheduling the number of steel balls, can control the number of steel balls of different diameters in the two bins in the barrel, and reasonably matches the steel balls of different specifications according to the matching data given by the steel ball ratio module;

[0014] The processing module is connected with the control module, the scheduling module and the data acquisition module, provides a processing environment for the material, sets double bins in the device, the double bins are a coarse crushing bin and a fine crushing bin respectively, the steel balls are arranged in the coarse crushing bin, the fine crushing bin is filled with forged rounds, the running state of the device is monitored and adjusted in real time by using sensors and intelligent technology, the ratio of the steel balls is optimized according to the actual operation data, the grinding efficiency is improved and the energy consumption is reduced.

[0015] By adopting the above technical scheme, the grinding efficiency of the ball mill can be significantly improved, the production efficiency of the whole process is improved, the operation of the ball mill is more stable, unnecessary energy consumption is reduced, and the production cost is reduced.

[0016] Specifically, it also includes a steel ball storage module connected with the steel ball ratio module, which is used for storing steel balls of different diameters and recording the specific diameter and weight data of each steel ball.

[0017] By adopting the technical scheme, the diameter and weight of the steel ball can be recorded and uploaded each time the steel ball is collected, the wear condition of the steel ball can be mastered and understood in real time, the filling state of the ball in the ball mill can be evaluated, the operation parameter adjustment of the ball mill is provided with reference, the production capacity and efficiency of the ball mill are optimized, and the crushing effect of the cement raw material and the product quality are improved.

[0018] The application further provides a ball arrangement method for a cement grinding mill, comprising the following steps:

[0019] S1: the specifications and models of the ball mill are input into the system, so that appropriate ball diameters and ball weights are selected, and the physical properties and chemical properties of the material are input, so as to cooperate with the calculation of the mathematical model, and the information is sent to the control center, and the control center sends the data to the calculation center for data calculation;

[0020] S2: the control center constructs a model, and the required friction coefficient and other related parameters can be obtained through the mathematical model, so as to guide the ball mill ball arrangement of the cement enterprise in actual production, and the control center adjusts and optimizes the ball arrangement scheme according to the calculated ball arrangement data, and reasonably arranges the steel balls of different specifications;

[0021] S3: the maximum ball diameter and the average ball diameter are determined according to the maximum particle size and the average particle size of the material to be ground, the maximum ball diameter should be greater than the maximum particle size of the material to be ground, and the average ball diameter is determined according to the particle size distribution of the material, if the particle size of the material to be ground changes greatly, a plurality of specifications of steel balls should be selected, otherwise, fewer specifications can be selected, and the composition proportion of each specification of steel ball is set according to the "small at both ends and large in the middle" arrangement principle of the grinding body and the particle size distribution characteristics of the material;

[0022] S4: the data calculated by the mathematical model is sent to the calculation center through the control center, and the friction coefficient between the ball and the liner plate of the ball mill, the collision crushing force between the ball and the cement raw material, the impact crushing force between the ball and the cement raw material, and the number and filling rate of the ball are calculated;

[0023] S5: two bins are arranged in the ball mill barrel, one of which is a coarse crushing bin filled with steel balls, and the other is a fine crushing bin filled with forged rounds, the diameter and height size of the forged rounds include 12mmx12mm, 14mmx14mm, 16mmx16mm and 18mmx18mm, different specifications of steel balls are sequentially added to the coarse crushing bin of the ball mill according to the set composition proportion, the grinding efficiency and the wear rate of the mill liner are recorded during the processing, and the recorded data is collected and fed back at any time, appropriate ball diameters can be selected according to the actual situation to avoid being too large or too small, so as to maintain appropriate impact times and material flow rate, and until the most suitable steel ball composition proportion is arranged.

[0024] By adopting the above technical scheme, by optimizing the design and structure of the cement ball mill, it can be more stable and reliable to run, reduce the maintenance cost, adopt intelligent control technology to realize the automatic operation and optimization control of the cement ball mill, improve the production efficiency, and reduce the human operation error.

[0025] Specifically, in S2, the construction step of the mathematical model includes:

[0026] Assuming that the friction coefficient (μ) is related to the hardness (H) of the cement raw material, the density (ρ) and the grindability (K), the following mathematical model can be established:

[0027] μ=f(H,ρ,K)

[0028] Where f is a function relationship representing the relationship between the friction coefficient and the physical properties of the cement raw material, and the specific function form needs to be fitted and verified according to the actual situation;

[0029] In addition, the contact stress (σ) between the ball and the ball mill liner and the impact crushing force (P) between the ball and the cement raw material also need to be considered. Assuming that the contact stress is related to the hardness of the cement raw material and the impact crushing force is related to the grindability of the cement raw material, the following mathematical model can be established:

[0030] σ=g(H);

[0031] P=h(K);

[0032] Where g and h are function relationships representing the relationship between the contact stress and the impact crushing force and the physical properties of the cement raw material, and the specific function form needs to be fitted and verified according to the actual situation;

[0033] Combining the above mathematical models, the relationship between the friction coefficient, the contact stress and the impact crushing force between the ball and the ball mill liner can be obtained:

[0034] μ=f(H,ρ,K);

[0035] σ=g(H);

[0036] P=h(K)。

[0037] By adopting the above technical scheme, the required friction coefficient and other related parameters can be obtained, thereby guiding the ball mill ball matching of the cement enterprise in actual production.

[0038] Specifically, in S4, to determine the friction coefficient between the ball and the ball mill liner, the physical properties of the cement raw material need to be considered, including:

[0039] Hardness: The hardness of the cement raw material determines the contact stress between the ball and the liner. Harder cement raw materials require greater contact stress for crushing, so harder liner materials and larger ball diameters need to be selected. Conversely, softer cement raw materials require the opposite.

[0040] Density: The density of the cement raw material determines the weight distribution between the ball and the liner. High-density cement raw materials require greater ball weight to generate sufficient impact force, while low-density cement raw materials require the opposite.

[0041] Grindability: The grindability of the cement raw material determines the friction coefficient between the ball and the liner. Poorly grindable cement raw materials require greater friction for crushing, so liner materials with a larger friction coefficient and harder balls need to be selected. Conversely, well-grindable cement raw materials require the opposite.

[0042] By adopting the above technical solutions, a mathematical model can be established for calculation based on the relationship between the friction coefficient between the ball and the liner, the collision crushing force between the ball and the cement raw material, and the impact crushing force between the ball and the cement raw material.

[0043] Specifically, in S4, the friction coefficient includes:

[0044] Dynamic friction coefficient (μk): μk = Ff / Fn, where Ff is the dynamic friction force and Fn is the normal pressure perpendicular to the contact surface.

[0045] Static friction coefficient (μs): μs = Ff / Fn, where Ff is the static friction force and Fn is the normal pressure perpendicular to the contact surface.

[0046] Sliding friction coefficient (μ): μ = Ft / Fn, where Ft is the tangential friction force and Fn is the normal pressure perpendicular to the contact surface.

[0047] By adopting the above technical solutions, the friction performance between the ball and the liner can be evaluated, providing a basis for the design and optimization of the ball mill.

[0048] Specifically, in S4, the calculation formula for the collision crushing force is:

[0049] P = (1 / 2) × m × v^2 × A;

[0050] Where:

[0051] P is the collision crushing force (unit: Newton)

[0052] m is the mass of the ball (unit: kilograms)

[0053] v is the collision speed of the ball (unit: meters / second)

[0054] A is the collision area of the ball (unit: square meters).

[0055] By adopting the technical scheme, the breaking capacity of the ball on the cement raw material can be evaluated, and reference is provided for adjustment of operation parameters of the ball mill.

[0056] Specifically, in S4, the calculation formula of the impact breaking force is:

[0057] P = (1 / 2) * m * v^2 * sin(2θ);

[0058] wherein:

[0059] P is the impact breaking force (unit: Newton)

[0060] m is the mass of the ball (unit: kilograms)

[0061] v is the impact speed of the ball (unit: meters / second)

[0062] θ is the collision angle between the ball and the cement raw material (unit: radian).

[0063] Specifically, in S4, the calculation process of the number of balls and the filling rate is:

[0064] Firstly, the number of balls (N) can be calculated according to the production capacity and the rotating speed (n) of the ball mill, and the calculation formula is: N = (3600 * V) / (π * d * n);

[0065] wherein, V is the production capacity (unit: cubic meters / hour)

[0066] d is the diameter of the ball mill (unit: meters)

[0067] n is the rotating speed of the ball mill (unit: revolutions / minute);

[0068] Then, the filling rate (ε) can be calculated according to the number of balls and the effective volume (Vv) of the ball mill, and the calculation formula is:

[0069] ε = N / Vv;

[0070] wherein, Vv is the effective volume of the ball mill (unit: cubic meters).

[0071] Specifically, in S5, the data to be recorded include:

[0072] Production capacity: the production capacity of the ball mill is observed, and if the ball arrangement is appropriate, the production capacity of the ball mill will reach the best state, the unit power consumption is low, and the running rate of the ball mill is high;

[0073] Grinding efficiency: the rationality of the ball arrangement directly affects the grinding efficiency, and if the ball arrangement is appropriate, the grinding efficiency will reach the best state, and the material monomer dissociation degree will also be improved;

[0074] Liner wear: the wear of the ball matching liner is also large, if the ball matching is appropriate, the wear of the liner will slow down, thereby prolonging the service life of the liner;

[0075] Noise and vibration: when the ball matching is unreasonable, the ball mill will produce larger noise and vibration, if the ball matching is appropriate, these phenomena will be improved;

[0076] Steel ball breakage rate: the breakage rate is related to the grinding efficiency, the lower the breakage rate, the higher the grinding efficiency, and the higher the breakage rate, the lower the grinding efficiency, if the ball matching is appropriate, the breakage rate of the steel ball will be reduced.

[0077] Compared with the prior art, the beneficial effects of the application are:

[0078] 1. The cement grinding mill system and ball matching method of the application improve the grinding efficiency of the cement ball mill, reduce energy consumption, improve product quality, and through optimization of the design and structure of the cement ball mill, the cement ball mill can operate more stably and reliably, reduce maintenance cost, and adopt intelligent control technology to realize automatic operation and optimization control of the cement ball mill, improve production efficiency, and reduce human operation errors.

[0079] 2. The cement grinding mill system and ball matching method of the application can make the ball mill run more smoothly, reduce unnecessary energy consumption, reduce production cost, and through reasonable ball matching, the grinding efficiency of the ball mill can be significantly improved, thereby improving the production efficiency of the whole process, reducing the wear of the liner inside the ball mill, prolonging the service life, reducing the frequency of repair and replacement, reducing the maintenance cost, reducing the breakage rate of the steel ball, thereby reducing the pollution to the environment, making the grinding effect of the ball mill more uniform, and improving the quality of the product. BRIEF DESCRIPTION OF DRAWINGS

[0080] Figure 1 A block diagram of a cement grinding mill system is provided for the application;

[0081] Figure 2 A block diagram of an information input module in a cement grinding mill system is provided for the application;

[0082] Figure 3 A block diagram of a control module in a cement grinding mill system is provided for the application;

[0083] Figure 4 A block diagram of a data acquisition module in a cement grinding mill system is provided for the application;

[0084] Figure 5 A flowchart of a cement grinding mill ball matching method is provided for the application. DETAILED DESCRIPTION

[0085] In order to enable a more complete understanding of the above-mentioned objects, features and advantages of the present application, the application will be described in further detail below with reference to the accompanying drawings and specific embodiments. It is to be noted that the embodiments of the present application and the features in the embodiments can be combined with each other if there is no conflict.

[0086] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that the present application can be practiced without the specific details and other implementations can be employed. Therefore, the scope of the present application is not limited to the specific embodiments disclosed in the following description.

[0087] Reference Figures 1-4The utility model provides a cement grinding mill system, including control module, control module includes equipment control unit, instruction sending unit, model construction unit and information processing unit, control module is used for to the control of equipment operation state, also sends control instruction, establishes mathematical model simultaneously and calculates, obtains the friction coefficient and other related parameters needed, thereby instructs the cement enterprise ball mill of actual production ball, control module is connected with information entry module, information entry module includes equipment information entry unit, material information entry unit and running information entry unit, information entry module is used for to the size and model of ball mill are entered, so as to select the ball diameter and ball weight suitable, also to the physical property and chemical property of material are entered, to cooperate the calculation of mathematical model, control module is connected with data acquisition module, data acquisition module includes material collection unit, equipment rotating speed collection unit, weight collection unit and information processing unit, data acquisition module is used for to the grinding data of material are collected, also to the running rotating speed of equipment and the data of equipment bearing weight are collected, simultaneously to the data of collection is sent and stored backup, control module is connected with calculation module, calculation module is used for according to the material data of collection, calculates the friction coefficient between ball and ball mill lining, also can calculate the collision crushing force between ball and material and the impact crushing force between ball and material, according to the relationship between the friction coefficient between ball and lining, the collision crushing force between ball and material and the impact crushing force between ball and material, and provide data support for the proportioning of steel ball, control module is connected with steel ball proportioning module, calculation module is connected with steel ball proportioning module, steel ball proportioning module adjusts and optimizes the ball proportioning scheme according to the data generated when equipment operates, reasonably proportioning steel ball of different sizes, and considers the grinding efficiency and the wear rate of mill lining, selects the appropriate ball diameter according to the actual situation, avoids too big or too small, to maintain proper impact frequency and material flow rate, control module is connected with scheduling module, steel ball proportioning module is connected with scheduling module, scheduling module is used for the scheduling of steel ball quantity, can control the quantity of different diameter steel ball in the two bins in the barrel, reasonably proportioning steel ball of different sizes according to the proportioning data given by steel ball proportioning module, control module is connected with processing module, scheduling module is connected with processing module, processing module is connected with data acquisition module, processing module provides processing environment for material, double bins are arranged in the equipment, and the double bins are coarse crushing bin and fine crushing bin respectively, steel ball is arranged in the coarse crushing bin, and forged round is filled in the fine crushing bin, the running state of equipment is monitored and adjusted in real time by using sensor and intelligent technology, the proportioning of steel ball is optimized according to actual operation data, the grinding efficiency is improved and the energy consumption is reduced.

[0088] It is to be noted that the embodiment further comprises a steel ball storage module, which is connected with the steel ball proportioning module, and is used for storing steel balls with different diameters and recording the specific diameter and weight data of each steel ball.

[0089] With reference to Figure 5 The embodiment further provides a ball proportioning method for a cement grinding mill, comprising the following steps:

[0090] S1: the specifications and models of the ball mill are input into a system so as to select appropriate ball diameters and ball weights, and the physical and chemical properties of the material are input into the system so as to match the calculation of a mathematical model, and the information is sent to a control center, and the control center sends the data to a calculation center for data calculation;

[0091] S2: the control center constructs a model according to the data, and the required friction coefficient and other related parameters can be obtained through the mathematical model, so as to guide the ball mill ball proportioning of the cement enterprise in actual production, and the control center adjusts and optimizes the ball proportioning scheme according to the calculated ball proportioning data, and reasonably proportioning steel balls with different specifications;

[0092] S3: the maximum ball diameter and the average ball diameter are determined according to the maximum particle size and the average particle size of the material to be ground, the maximum ball diameter should be greater than the maximum particle size of the material to be ground, and the average ball diameter is determined according to the particle size distribution of the material, if the particle size of the material to be ground changes greatly, a plurality of specifications of steel balls should be selected, otherwise, fewer specifications can be selected, and the composition proportion of each specification of steel ball is set according to the proportioning principle of “small at both ends and large in the middle” of the grinding body and the particle size distribution characteristics of the material;

[0093] S4: the data calculated by the mathematical model is sent to the calculation center through the control center, and the friction coefficient between the ball and the liner plate of the ball mill, the collision crushing force between the ball and the cement raw material, the impact crushing force between the ball and the cement raw material, and the number and filling rate of the ball are calculated;

[0094] The friction coefficient comprises:

[0095] The dynamic friction coefficient (μk) is μk=Ff / Fn, wherein Ff is the dynamic friction force, and Fn is the normal pressure perpendicular to the contact surface;

[0096] The static friction coefficient (μs) is μs=Ff / Fn, wherein Ff is the static friction force, and Fn is the normal pressure perpendicular to the contact surface;

[0097] The sliding friction coefficient (μ) is μ=Ft / Fn, wherein Ft is the tangential friction force, and Fn is the normal pressure perpendicular to the contact surface;

[0098] The calculation formula of the collision crushing force is P=(1 / 2)×m×v^2×A;

[0099] wherein:

[0100] P is the impact breaking force (unit: Newton)

[0101] m is the mass of the ball (unit: kilogram)

[0102] v is the impact speed of the ball (unit: meter / second)

[0103] A is the impact area of the ball (unit: square meter);

[0104] The calculation formula of the impact breaking force is: P = (1 / 2) x m x v^2 x sin(2θ);

[0105] wherein:

[0106] P is the impact breaking force (unit: Newton)

[0107] m is the mass of the ball (unit: kilogram)

[0108] v is the impact speed of the ball (unit: meter / second)

[0109] θ is the impact angle between the ball and the cement raw materials (unit: radian);

[0110] The calculation process of the number and filling rate of the balls is as follows:

[0111] Firstly, the number of balls (N) can be calculated according to the production capacity and the rotating speed (n) of the ball mill, and the calculation formula is: N = (3600 x V) / (π x d x n);

[0112] wherein, V is the production capacity (unit: cubic meter / hour)

[0113] d is the diameter of the ball mill (unit: meter)

[0114] n is the rotating speed of the ball mill (unit: revolutions / minute);

[0115] Then, the filling rate (ε) can be calculated according to the number of balls and the effective volume (Vv) of the ball mill, and the calculation formula is:

[0116] ε = N / Vv;

[0117] wherein, Vv is the effective volume of the ball mill (unit: cubic meter);

[0118] S5: Two compartments are set in the ball mill barrel, one of which is a coarse crushing compartment, and the other is a fine crushing compartment. Steel balls are filled in the coarse crushing compartment, and forged rounds are filled in the fine crushing compartment. The diameter and height of the forged rounds include 12mmx12mm, 14mmx14mm, 16mmx16mm, and 18mmx18mm. Different specifications of steel balls are added to the coarse crushing compartment of the ball mill in a set composition ratio. The grinding efficiency and the wear rate of the mill liner are recorded during the processing, and the recorded data are collected and fed back in real time. The appropriate ball diameter can be selected according to the actual situation to avoid being too large or too small, so as to maintain the appropriate impact frequency and material flow rate, until the most suitable steel ball composition ratio is obtained;

[0119] It should be noted that the data to be recorded include:

[0120] Production capacity: If the ball arrangement is suitable, the production capacity of the ball mill will reach the best state, the unit power consumption will be lower, and the operation rate of the ball mill will be higher;

[0121] Grinding efficiency: The rationality of ball arrangement directly affects the grinding efficiency. If the ball arrangement is suitable, the grinding efficiency will reach the best state, and the material monomer dissociation degree will also be improved;

[0122] Liner wear: The ball arrangement also has a greater impact on the wear of the liner. If the ball arrangement is suitable, the wear of the liner will slow down, thereby prolonging the service life of the liner;

[0123] Noise and vibration: If the ball arrangement is not reasonable, the ball mill will produce a lot of noise and vibration. If the ball arrangement is suitable, these phenomena will be improved;

[0124] Steel ball breakage rate: The breakage rate is related to the grinding efficiency. The lower the breakage rate, the higher the grinding efficiency, and the higher the breakage rate, the lower the grinding efficiency. If the ball arrangement is suitable, the breakage rate of the steel ball will be reduced.

[0125] It should be noted that in S4, the friction coefficient between the ball and the ball mill liner needs to be determined, and the physical properties of the cement raw material need to be considered, including:

[0126] Hardness: The hardness of the cement raw material determines the contact stress between the ball and the liner. Harder cement raw materials require greater contact stress for crushing, so harder liner materials and larger ball diameters need to be selected. Conversely, softer cement raw materials are the opposite;

[0127] Density: The density of the cement raw material determines the weight distribution between the ball and the liner. High-density cement raw materials require greater ball weight to generate sufficient impact force, while low-density cement raw materials are the opposite;

[0128] Grindability: the grindability of the cement raw material determines the friction coefficient between the ball and the liner, the cement raw material with poor grindability needs greater friction to break, so the liner material with larger friction coefficient and harder ball need to be selected; the cement raw material with good grindability is the opposite.

[0129] It should be noted that in S2, the construction step of the mathematical model includes:

[0130] Assuming that the friction coefficient (mu) is related to the hardness (H) of the cement raw material, the density (rho) and the grindability (K), the following mathematical model can be established:

[0131] mu = f(H, rho, K)

[0132] Where f is a function relationship representing the relationship between the friction coefficient and the physical properties of the cement raw material, the specific function form needs to be fitted and verified according to the actual situation;

[0133] In addition, the contact stress (sigma) between the ball and the ball mill liner and the impact breaking force (P) between the ball and the cement raw material also need to be considered, assuming that the contact stress is related to the hardness of the cement raw material and the impact breaking force is related to the grindability of the cement raw material, the following mathematical model can be established:

[0134] sigma = g(H);

[0135] P = h(K);

[0136] Where g and h are function relationships representing the relationship between the contact stress and the impact breaking force and the physical properties of the cement raw material, similarly, the specific function form needs to be fitted and verified according to the actual situation;

[0137] Combining the above mathematical models, the relationship between the friction coefficient, the contact stress and the impact breaking force between the ball and the ball mill liner can be obtained:

[0138] mu = f(H, rho, K);

[0139] sigma = g(H);

[0140] P = h(K).

[0141] The technical progress obtained by the present application relative to the prior art is: the ball matching method provided by the present application can significantly improve the grinding efficiency of the ball mill through reasonable ball matching, thereby improving the production efficiency of the entire process, making the operation of the ball mill more stable, reducing unnecessary energy consumption and production cost, reducing the wear of the liner inside the ball mill, prolonging the service life, and reducing the frequency of maintenance and replacement, thereby reducing the maintenance cost. The intelligent control technology can realize the automatic operation and optimal control of the cement ball mill, improve the production efficiency and reduce human operation errors.

Claims

1. A cement grinding mill system characterized by, Include: Control module, the control module includes device control unit, instruction sending unit, model construction unit and information processing unit, the control module is used for controlling the device running state, also sends control instruction, establishes mathematical model for calculation at the same time, obtains the required friction coefficient and other related parameters, thereby guiding the cement enterprise ball mill ball in actual production; Information input module, the information input module includes device information input unit, material information input unit and running information input unit, the information input module is connected with the control module, the information input module is used for inputting the size and model of the ball mill, in order to select the appropriate ball diameter and ball weight, also input the physical properties and chemical properties of the material, in order to cooperate with the calculation of mathematical model; Data acquisition module, the data acquisition module includes material acquisition unit, equipment rotating speed acquisition unit, weight acquisition unit and information processing unit, the data acquisition module is connected with the control module, the data acquisition module is used for collecting the grinding data of the material, also collecting the running speed of the equipment and the data of the equipment load weight, while sending and storing backup the collected data; Calculation module, the control module is connected with the calculation module, the calculation module is used for calculating the friction coefficient between the ball and the ball mill liner according to the collected material data, also can calculate the collision crushing force between the ball and the material and the impact crushing force between the ball and the material, according to the relationship between the friction coefficient between the ball and the liner, the collision crushing force between the ball and the material and the impact crushing force between the ball and the material, and provides data support for the proportioning of steel ball; Steel ball proportioning module, the control module is connected with the steel ball proportioning module, the calculation module is connected with the steel ball proportioning module, the steel ball proportioning module adjusts and optimizes the ball proportioning scheme according to the data generated during equipment operation, reasonably proportioning steel balls of different specifications, and considering the grinding efficiency and the wear rate of the mill liner, selecting the appropriate ball diameter according to the actual situation, avoiding too large or too small, to maintain appropriate impact times and material flow rate; Scheduling module, the control module is connected with the scheduling module, the steel ball proportioning module is connected with the scheduling module, the scheduling module is used for scheduling the number of steel balls, can control the number of steel balls of different diameters in the two bins in the barrel, reasonably proportioning steel balls of different specifications according to the proportioning data given by the steel ball proportioning module; Processing module, the control module is connected with the processing module, the scheduling module is connected with the processing module, the processing module is connected with the data acquisition module, the processing module provides processing environment for the material, double bin is arranged in the equipment, double bin is coarse crushing bin and fine crushing bin respectively, steel balls are arranged in the coarse crushing bin, forged round is filled in the fine crushing bin, the running state of the equipment is monitored and adjusted in real time by using sensor and intelligent technology, the proportioning of steel balls is optimized according to the actual operation data, the grinding efficiency is improved and the energy consumption is reduced.

2. A cement grinding mill system as claimed in claim 1, wherein, The steel ball storage module is connected with the steel ball proportioning module, and is used for storing steel balls with different diameters and recording specific diameter and weight data of each steel ball.

3. A ball proportioning method for a cement grinding mill, using the cement grinding mill system according to any one of claims 1-2, comprising the following steps: S1: inputting the specifications and models of the ball mill into the system to select appropriate ball diameters and ball weights, and inputting the physical and chemical properties of the material to match the calculation of the mathematical model, and sending the information to the control center, which sends the data to the calculation center for data calculation; S2: the control center constructs a model from the data, and the mathematical model can obtain the required friction coefficient and other related parameters, thereby guiding the ball mill ball proportioning of the cement enterprise in actual production, and the control center adjusts and optimizes the ball proportioning scheme according to the calculated ball proportioning data to reasonably proportion different specifications of steel balls; S3: the maximum ball diameter and the average ball diameter are determined according to the maximum particle size and the average particle size of the material to be ground, the maximum ball diameter should be greater than the maximum particle size of the material to be ground, and the average ball diameter is determined according to the particle size distribution of the material, if the particle size of the material to be ground varies greatly, a plurality of specifications of steel balls should be selected, otherwise, fewer specifications can be selected, and the composition ratio of each specification of steel balls is set according to the proportioning principle of "small at both ends and large in the middle" of the grinding body and the particle size distribution characteristics of the material; S4: the data calculated by the mathematical model is sent to the calculation center through the control center to calculate the friction coefficient between the ball and the ball mill liner, the collision crushing force between the ball and the cement raw material, the impact crushing force between the ball and the cement raw material, and the number and filling rate of the ball; S5: two compartments are provided in the ball mill barrel, one of which is a coarse crushing compartment filled with steel balls, and the other is a fine crushing compartment filled with forged rounds, the diameter and height of the forged rounds include 12mmx12mm, 14mmx14mm, 16mmx16mm and 18mmx18mm, different specifications of steel balls are sequentially added to the coarse crushing compartment of the ball mill according to the set composition ratio, the grinding efficiency and the wear rate of the mill liner are recorded during the processing, and the recorded data is collected and fed back at any time, and appropriate ball diameter can be selected according to the actual situation to avoid too large or too small, so as to maintain appropriate impact times and material flow rate, until the most suitable steel ball composition ratio is obtained.

4. A method of sizing the balls of a cement mill according to claim 3, characterized in that, In S2, the construction step of the mathematical model includes: Assuming that the friction coefficient (μ) is related to the hardness (H), density (ρ) and grindability (K) of the cement raw material, the following mathematical model can be established: μ=f(H, ρ, K) Where f is a function relationship representing the relationship between the friction coefficient and the physical properties of the cement raw material, and the specific function form needs to be fitted and verified according to the actual situation; In addition, the contact stress (σ) between the ball and the liner of the ball mill and the impact crushing force (P) between the ball and the cement raw material also need to be considered. Assuming that the contact stress is related to the hardness of the cement raw material and the impact crushing force is related to the grindability of the cement raw material, the following mathematical models can be established: σ = g(H); P = h(K); where g and h are the functional relationships between the contact stress and the impact crushing force and the physical properties of the cement raw material, respectively. The specific functional forms need to be fitted and verified according to the actual situation. Based on the above mathematical models, the relationship between the friction coefficient, the contact stress, and the impact crushing force between the ball and the liner of the ball mill can be obtained: μ = f(H, ρ, K); σ = g(H); P = h(K).

5. A method of sizing the balls of a cement mill according to claim 3, characterized in that, In S4, to determine the friction coefficient between the ball and the liner of the ball mill, the physical properties of the cement raw material need to be considered, including: Hardness: The hardness of the cement raw material determines the contact stress between the ball and the liner. Harder cement raw material requires greater contact stress for crushing, so harder liner material and larger ball diameter need to be selected. Conversely, softer cement raw material is the opposite. Density: The density of the cement raw material determines the weight distribution between the ball and the liner. High-density cement raw material requires greater ball weight to generate sufficient impact force, while low-density cement raw material is the opposite. Grindability: The grindability of the cement raw material determines the friction coefficient between the ball and the liner. Poor grindability of the cement raw material requires greater friction force for crushing, so liner material with larger friction coefficient and harder ball need to be selected. Conversely, good grindability of the cement raw material is the opposite.

6. A method of sizing the balls of a cement mill according to claim 3, characterized in that, In S4, the friction coefficient includes: Dynamic friction coefficient (μk): μk = Ff / Fn, where Ff is the dynamic friction force and Fn is the normal pressure perpendicular to the contact surface. Static friction coefficient (μs): μs = Ff / Fn, where Ff is the static friction force and Fn is the normal pressure perpendicular to the contact surface. Sliding friction coefficient (μ): μ = Ft / Fn, where Ft is the tangential friction force and Fn is the normal pressure perpendicular to the contact surface.

7. A method of sizing the balls of a cement mill according to claim 3, characterized in that, In S4, the calculation formula of the impact crushing force is: P = (1 / 2) × m × v^2 × A; where: P is the impact crushing force (unit: Newton) m is the mass of the ball (unit: kilograms) v is the collision speed of the ball (unit: meters / second) A is the collision area of the ball (unit: square meters).

8. A method of sizing the balls of a cement mill according to claim 3, characterized in that, In S4, the calculation formula of the impact crushing force is: P = (1 / 2) × m × v^2 × sin(2θ); where: P is the impact crushing force (unit: Newton) m is the mass of the ball (unit: kilograms) v is the impact speed of the ball (unit: meters / second) θ is the collision angle between the ball and the cement raw material (unit: radians).

9. A method of sizing the balls of a cement mill according to claim 3, characterized in that, In S4, the calculation process of the number of balls and the filling rate is as follows: First, the number of balls (N) can be calculated according to the production capacity and the rotational speed (n) of the ball mill, with the calculation formula being: N = (3600 × V) / (π × d × n); where V is the production capacity (unit: cubic meters / hour) d is the diameter of the ball mill (unit: meters) n is the rotational speed of the ball mill (unit: revolutions / minute). Then, the filling rate (ε) can be calculated according to the number of balls and the effective volume (Vv) of the ball mill, and the calculation formula is: ε = N / Vv; Wherein, Vv is the effective volume of the ball mill (unit: cubic meters).

10. A method of sizing the balls of a cement mill according to claim 3, characterized in that, In the S5, the data to be recorded include: Production capacity: observe the production capacity of the ball mill, if the ball arrangement is appropriate, the production capacity of the ball mill will be in the best state, the unit power consumption is low, and the operation rate of the ball mill is high; Grinding efficiency: the rationality of ball arrangement directly affects the grinding efficiency, if the ball arrangement is appropriate, the grinding efficiency will be in the best state, and the single body dissociation degree of the material will also be improved; Liner wear: the ball arrangement also has a large wear on the liner, if the ball arrangement is appropriate, the wear of the liner will slow down, thereby prolonging the service life of the liner; Noise and vibration: when the ball arrangement is not reasonable, the ball mill will produce a large noise and vibration, if the ball arrangement is appropriate, these phenomena will be improved; Steel ball breakage rate: the breakage rate is related to the grinding efficiency, the lower the breakage rate, the higher the grinding efficiency, and the higher the breakage rate, the lower the grinding efficiency, if the ball arrangement is appropriate, the breakage rate of the steel ball will be reduced.

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