Abstract:
In view of the problem of air leakage spontaneous combustion caused by the full development of coal and rock fissures in the complex goaf of the close coal seam in 2201 working face mining area of Huainan Xinji No.2 coal mine, the air leakage sources and air leakage sinks of the working face are determined by using a variety of methods such as pressure difference measurement at the key position, energy measurement and gas composition analysis.On this basis, the dual tracer gas technology of SF
6 and CF
2ClBr is used to further analyze the flow field and complex air leakage network system in goaf.According to the above research results, the comprehensive three-dimensional air leakage prevention and control technology of “injection+secondary sealing ring leakage+two-way two-line isolation” is proposed and applied in the field.The results show that the air leakage source of 2201 working face mining area is 3
# observation point and 2
# observation point of 220115 working face transportation roadway and 220112 working face transportation roadway sealing wall.The air leakage sink is 220108 working face floor roadway sealing wall, 220116 working face return airway and transportation roadway sealing wall, 220112 working face return airway and high pumping roadway sealing wall.There are four air leakage routes in 2201 working face mining area, forming a “multi-source and multi-sink” goaf air leakage flow field.Through the application of comprehensive three-dimensional air leakage prevention and control technology, the CO concentration in the old goaf of 2201 working face mining area is basically 0, and the O
2 concentration is within a reasonable range, which effectively controls the air leakage in 2201 working face mining area and ensures the safe production of 2201 working face mining area.