Study And Application Of Pressure Relief Gas Migration In Fully Mechanized Coal Caving In Gently Inclined Coal Seam

Gas and coal coexist coexistence,it is a serious threat to the safety of the mine production on the one hand,on the other hand,it is clean and efficient energy.Therefore,the implementation of the safety of the two resources of coal and gas has a positive effect on reducing the mine gas disaster accidents and optimizing the energy structure.Based on the research background of the gently inclined coal seam in the Liu Huang Gou coal mine,the evolution law of the fractured field and the migration and aggregation relation of the internal pressure relief gas are studied from the theoretical deduction,the numerical simulation analysis and the field industrial test and analysis.The research results are applied to the site,and the preliminary study is made as follows.The results are as follows:(1)Based on the geological conditions of the coal mining in the Liu Huang Gou,the discrete element software UDEC2D4.0 is used to simulate and analyze the influence of different coal seam dip angles on the stress,displacement,the evolution law and distribution characteristics of the mining fracture,and the fractal theory is used to analyze the distribution characteristics of the fractured rock mining.(2)In view of the complexity of the fracture distribution characteristics of the overlying strata in the gently inclined coal seam,the time and space evolution law of the fractured mining fracture in the gently inclined coal seam is summarized and analyzed by means of borehole peephole and m icroseismic monitoring in the site of the Liu Huang Gou coal mine,and the simulation results of the distribution characteristics of the fractured rock fracture in the slowly inclined coal seam are verified.(3)Based on the distribution characteristics of the fractured mining fracture in the gently inclined coal seam,the gas flow model in the fractured field is established by using the theory of seepage mechanics and hydromechanics.The gas migration and accumulation process in the mining fracture field of gently inclined coal seam is simulated by the numerical simulation software COMSOL,and the gas migration law of the mining fracture field in the gently inclined coal seam is obtained.(4)Based on the above research results,a reasonable and effective gas extraction technology under the influence of slit coal seam mining is put forward,and the industrial test is carried out in the field,which has achieved remarkable results,effectively improving the efficiency of pressure relief gas extraction,and ensuring the safe and efficient production of the working face.