Study On Gas Migration Of Protected Layer Law And Protection Scope Of Xieyi Mine

With the increase of the depth of modern coal mining,coal and gas outburst has seriously affected the safe and efficient mining.The most effective and economic regional measure to prevent and control it is to carry out protective layer mining,which need more in-depth research,this paper takes Huainan mining limited liability company Wangfenggang Xieyi mine protected layer B8 as the research object,studying the theory analysis method and numerical simulation analysis by the scene.And the research contents are as follows:(1)Analysis of stress field,displacement field and gas flow theory of protective layer miningIn this paper,according to the theoretical knowledge of the solid gas coupling model of protective layer mining,the basic theory is introduced and analyzed based on the equation of COMSOL software.And the relationship between several important variables in solid gas coupling is derived.(2)Numerical simulation of stress,displacement and gas migration in protective layer miningOn the basis of theoretical analysis and numerical simulation on gas solid flow coupling model is established and the coal and rock deformation of the gas of the gas flow was simulated using COMSOL software;The stress field,displacement field and gas migration,and the variation of the variable parameters of gas-solid coupled volumetric strain and porosity are analyzed.At the same time,the situation of drilling drainage in protective layer mining is simulated,and compared the change of gas pressure,stress field and displacement field with the situation when mining without drilling.(3)On the protection layer mining field testIn this paper,Wangfenggang Xieyi mine as a test point,the B9b coal seam is taken as the upper protective layer,and the B8 coal seam below is the protective layer.the process and method of measuring the gas pressure and gas content are introduced,variation of coal mining in the process of gas pressure and gas content were measured to determine the pressure relief angle,and the simulation results are compared with the simulation results.