Comprehensive prevention and control technology of

In response to the comprehensive gas prevention and control technology of high gassy mines,

1.1 transform the ventilation system, improve the ventilation capacity, and adhere to the fixed production by wind

in 2001, the East and West return air shafts of the mine were transformed and used BDK axial-flow energy-saving fans, increasing the total air intake of the mine by 2880 m ⊃/Min, reduce mine air leakage by 311 m ⊃/Min, increase the mine ventilation production capacity by 660000 t/a, reduce the motor power by 150 kW, and save an average of 500000 yuan of electricity annually. To solve the problem of insufficient ventilation capacity of the mine, the ability and reliability of the mine ventilation system have been significantly improved

1.2 optimize the ventilation items of the mine. Compared with traditional materials, the raw materials required for unfamiliar production are also the same, reducing the ventilation resistance

in view of the disrepair of the main roadway of the mine, the small section, the increase of wind resistance, and the difficulty in improving the ventilation capacity, the mine has specially set up a roadway repair team to expand the whole main ventilation roadway to 10.5m ⊃; The cross-section U-shaped steel support roadway is 3800 m in total. At the same time, each downhill mining area has achieved a special return air roadway, with a total of 3000 m of newly excavated special return air roadway, and the ventilation network has been shortened by 860 m, achieving the goals of reducing resistance, increasing air and reducing consumption in the mine

1.3 improve the ventilation facilities, optimize the ventilation system, upgrade and transform the mechanical and electrical facilities in advance

after the gas dynamic phenomenon appeared in the heading face of the coal roadway down the hill, the ventilation, monitoring, mechanical and electrical systems were upgraded and transformed in strict accordance with the standards of the outburst mine, and the bolts were used to reinforce and thicken the air door wall. The temporary ventilation facilities were all cancelled and the reverse wind prevention device was installed, A group of compressed air self rescue devices are installed every 50 m in the main roadway and heading roadway, and all electromechanical facilities are upgraded according to the requirements of underground electrical appliances in high outburst mines, so as to continuously improve the working efficiency of the tension machine

1 . 4. Carry out the reliability evaluation of the mine ventilation system

carry out the anti wind drill and the optimization design and reliability evaluation of the mine ventilation system once a year, calculate the anti wind rate and the mine ventilation resistance, so as to realize the reliability of the system and facilities, the stability of the air flow, and the strong disaster resistance ability. When disasters occur, the air flow is easy to control, which is convenient for rescue and disaster relief, and ensure that the ventilation system is reasonable, stable and reliable

2. Strengthen comprehensive gas prevention and control

2 1. Establish a professional team of gas prevention and control

establish a special organization and a professional team of gas drainage and prediction to be responsible for the management of gas drainage, outburst prevention, monitoring and safety equipment

2. 2 implement mine gas drainage

strictly implement the "Twelve character" policy of gas control, establish a gas drainage pump station underground and on the ground, and implement roof rock drilling drainage, high-level roadway drainage, advance shallow hole and roadway side drilling drainage, goaf drainage, upper corner buried pipe drainage, etc. in the underground blasting top coal caving face, high gas tunneling face and fully mechanized top coal caving face respectively, The phenomenon that the gas in the mining face often exceeds the limit is eliminated, and the output and footage are increased by 40%

2. 3 prevention and control of coal and gas outburst

since the gas dynamic phenomenon occurred in the 22121 downhill sub roadway heading face, all downhill coal roadway excavation heads have strictly controlled gas according to the "four in one" outburst prevention measures, including outburst risk prediction, effect test of outburst prevention measures, safety protection and other comprehensive prevention measures. The effect test is carried out by the drilling cuttings gas flow method, and the comprehensive index R value is taken as 6, Accumulated a lot of empirical data. Six new hydraulic drilling rigs have been put into the mine. In 2004, 4820 m advanced drilling holes were drilled in the heading face. So far, no gas outburst has occurred in the underground mining face

2. 4. Carry out the evaluation of gas prevention and control in the heading face. Look at the following introduction, we will know a lot.

the mine has established an evaluation leading group to regularly analyze the gas emission, coal and gas outburst risk, ventilation system, local ventilation, drainage system, monitoring system, explosion-proof facilities, compressed air self rescue, roof rock drilling drainage, roadway side advance drainage, drilling drainage, disaster avoidance copper room, geophysical exploration, drilling analysis The geological structure, equipment explosion-proof, electromechanical equipment protection, ventilation facilities and other projects are predicted, evaluated and verified, and the chief engineer organizes all business departments to jointly review the special evaluations respectively, put forward the comprehensive evaluation opinions on gas prevention and control of the heading face, decide whether excavation can be carried out, rectify the prevention and control measures, and determine the allowable excavation distance. Since June, 2004, the phenomena of coal and gas emission, extrusion and gas overrun caused by gas pressure, geological tectonic stress and other factors have been eliminated in the mining face of the mine

2. 5. The coal wall shallow hole high-pressure water injection is implemented in the mining face.

when the high-pressure water enters the coal seam, it flows, penetrates and diffuses along the crack, occupying the crack space and extruding the gas from the crack. The overhaul team injects the coal wall shallow hole high-pressure water, increasing the gas release, thus reducing the gas emission in the production process. At the same time, the shallow hole high-pressure water injection in the coal wall increases and expands the cracks in the coal seam, and the coal body is moist due to the full absorption of water, thus changing the physical and mechanical properties of the coal seam, effectively preventing the coal wall caving and roof falling in the mining face, thus eliminating the gas accumulation and gas overrun caused by the coal wall caving and roof falling