Study On Dynamic Balance Automatic Control Strategy Of Air Flow And Equipment Development In Large Area Composite Goaf

There are short-distance coal seams group storage in many mining areas in china,the new and old goafs connected to each other and form large-area complex goaf,because use bulk caving method in mining.Cause a large goaf air leakage and disaster gas swarm into working face from goaf and can make the spontaneous combustion fire more likely to occur.The spontaneous combustion prevention and control of large-area complex goaf in the process of short-distance and easy self-ignition coal seams group mining,is the major technical problems urgently need to be addressed in safety production of mine.Datong mining industry's mining condition is very complex that it has both mining of close-up coal seam group and hyper-thick coal seam group.They are both coal seam group with spontaneous combustion that make the prevention of spontaneous combustion extremely difficult.This paper is focusing on preventing spontaneous combustion of large area of composite goaf in the process of close-up coal seam mining that can easily cause spontaneous combustion in Jurassic layer of Datong mining area and start the research of automatic modulation control technology and key equipment in dynamic balance of air flow in large area goaf systematically.The industrial field test and application was carried out in the 81216 mechanized working face in no.14 coal seam,It focus on conquering the technical problem of preventing combustion in complex coal seam mining group,that has important theoretical guiding significance and application value to the coal mine safety production.Based on the theoretical analysis of gas flow and the theory of poisonous gas migration state,the basic parameters of ventilating condition in the stope are analyzed,starting from the tutorial model of regulating wind in the stope.The paper gives recommendation of adjusting the wind-shaving technology in large composite goaf and gives method of local equilibrium control of wind pressure in the large-scale composite goaf.Determine the return air lane observation point of wind pressure P3 permissible range of adjustment is P4(t)-h2,3(t),P4(t)-h2,3(t)+hk(t,L).The numerical simulation method is used to calculate the best optical parameter for the wind pressure balance in the 81216 working face,the pressure of air outlet pressure equalization point is higher than the upper goaf 30?50 Pa,received a large complex goaf automatic control method of dynamic balance.The key technologies and equipment of controlling and monitoring the large area of composite goaf air flow is developed through research.Through monitoring changes of the multi-point working condition parameter in the working face and the upper mined-out area by the automatic multi-parameter monitoring system and uploading the processed monitor parameters from the site sensor check substation processing monitor,the automatic control with variable frequency fan served to adjust the full servo automatic damper,wind window,to achieve the dynamic balance of the flowing wind's pressure in the working surface field.The paper puts forward a theory of balancing the wind dynamics in large composite goaves and studies upon the multi-sensor data fusion technology for dynamic balance system.,giving a solution of wind pressure fuzzy inference system based on particle swarm optimization.It also proposes a structure for the automatic control system in large-area composite mining surface,develops an operating platform hardware,a PLC control program,and a monitoring software based on MCGS,while putting a system design based on the expert double fan controlling program,effectively solve the problem of the double fan coordination control.The industrial field test was carried out in the 81216 mechanized working face in no.14 coal seam.Puts forward the comprehensive control of gas and spontaneous combustion technology solution of easily spontaneous combustion seam under conditions of large-area complex goaf,which combination of the automatic adjusting pressure technique,ground fissure filling and fire area management.Constructed with sealing wall,pressure regulating air door,automatic monitoring and inverter control as one of the air current dynamic automatic control system of large complex goaf,and the technical parameters of control system,the system automatically control standard and system startup procedure have been gave out.During the mining,air pressure of overlying old goaf and leakage air volume of this work face are command effectively.The phenomena of iconic spontaneous combustion gases exceed standard and high temperature dot are not appear,the gas and CO concentration are not overrun,ensure the work face safe mining,Created a remarkable economic,safety and social benefit.