Study On Dust Control Technology Of Dust Edge Tracking Spray In Fully Mechanized Mining Area

At present,the degree of mechanization of fully mechanized mining faces in my country is high,and the efficiency of coal mining is also increasing.Therefore,the content of dust generated is also high,which is the focus of dust prevention in the coal industry.At present,the most efficient and convenient dust reduction measure in fully mechanized mining face is to use high pressure to spray dust.However,the parameters of spray dust reduction are different,and the resulting dust reduction effect is also different.To this end,based on an in-depth understanding of the characteristics of fully mechanized coal mining face,the law of dust migration and nozzle atomization mechanism,the water spray pressure,the distance from the nozzle to the dust source point,the spray diffusion angle,and the nozzle atomization mechanism of the fully mechanized coal face The diameter and overlapping parameters of adjacent spray cross-section circles are the dust reduction parameters,and the objective function of the maximum dust reduction efficiency and the minimum water consumption is established.According to the shortcomings of genetic algorithm that is easy to mature in the later stage,the idea of a certain probability of accepting the difference in the simulated annealing algorithm is incorporated into the genetic algorithm mutation operator.Through the improved genetic algorithm,the two function values of dust reduction efficiency and water consumption of fully mechanized mining face are optimized to optimize these five dust reduction parameters,and the Pareto solution set is obtained.The entropy method is used to construct a program selection system,and the Pareto solution set is optimized,and then the optimal solution for the optimization of dust reduction parameters is obtained.In the research,it is shown that the Pareto solution set can more intuitively show the relationship between the checks and balances between different goals.According to the optimized parameters,the fog particle diameter and the fog particle survival time are selected as the screening indicators,and the entropy weight method is used to carry out the screening solution set.Preferred.After optimization,the dust reduction efficiency can reach 94.58%,and the water consumption is only 45.26L/min.Compared with an example of spray dust reduction in a coal mine,in the dust reduction area of 3.658×3.22×2.39 m,the dust reduction efficiency is 89.46%,and the water consumption is 52.17L/min.The optimized dust reduction efficiency improves it and reduces the water consumption by 6.91 L./min.In terms of the spray dust control system,most of the current fully mechanized coal mining faces use manual spray to reduce dust on the site where the dust concentration exceeds the standard,which not only increases the labor force,but also affects the physical and mental health of the staff.Therefore,it is extremely urgent to establish a complete remote control system for spray dust reduction at fully mechanized mining face.Research on dust concentration monitoring and real-time tracking of dust source points.Determine the main functions of the dust source tracking spray dust reduction system and the structure of one master and multiple slaves in a fully mechanized mining face.The control module between the master station and the slave station communicates through the RS-485 bus.The master station is composed of a master controller and a liquid level sensor.,Multiple slave stations are respectively distributed on the hydraulic support,composed of spray controller,infrared receiver,pressure sensor,dust concentration sensor,solenoid valve and nozzle mover.Analyze the main functions of the main controller and the spray controller,and use PLC as the core of the main controller's control module,which is mainly responsible for communicating with the upper computer and sorting out the data collected by the spray controller and issuing control commands.Using PLC S71200 as the control core of the spray controller,it is mainly responsible for the signal collection and execution control of the fully mechanized mining face.At the same time,complete the selection of various types of hardware and the writing of programs according to the way of signal acquisition.The position of the shearer is detected by the infrared receiving and transmitting device,the pressure sensor is used to detect the change in the pressure of the bracket valve to determine the position of the moving frame and the coal caving,the dust concentration sensor is used to detect the dust concentration exceeding signal,the liquid level sensor is Control the solenoid valve and the relay to control the start and stop of the spray nozzle and the power loss of the motor.Based on the design of the dust control system hardware and overall framework,combined with the requirements of monitoring software,the monitoring software is divided into three modules: human-computer interaction interface,data communication and database.Among them,the human-computer interaction interface module realizes the monitoring and display of system operation information through Win CC configuration software.The data communication module realizes the data communication between the host computer and the main controller.The database module realizes the tasks of processing,storing,querying and displaying system operating data through the SQL Server database management system.The monitoring software realizes the real-time storage and display of monitoring information such as the position and status of coal digging,shifting and caving processes,spray operation parameters,spray position and status,water pressure and water level in fully mechanized mining face,and can download spray operation Parameters,and provide an operation interface for the staff to set spray operating parameters and query work,etc.