Research On Risk Prediction And Prevention Technology Of Coal And Gas Outburst Based On Grey Theory

In China's energy consumption structure,coal has always accounted for a large proportion,while deep coal resources are mining,the depth of the mine continues to increase,coal seam gas pressure,gas content,gas emission and ground stress have an upward trend,coal The intensity and frequency of gas outburst also increase.Compared with shallow coal mining,the exploitation of deep coal resources is more affected by power disasters,and the exploitation of deep mines faces enormous challenges.Gas disaster prediction and prevention requires a breakthrough in theory and innovation on the technical level.This thesis is based on the 1061 working face in the 6th mining area of Linhuan Coal Mine:(1)Using research on coal and gas outburst mechanisms and influencing factors,determine the key influencing factors for coal and gas outburst to be geostress,gas pressure,and coal structure.(2)On-site and laboratory measurement of basic coal seam gas parameters in the research area.Field parameter measurements include coal seam gas pressure and coal seam gas content;laboratory tests include coal firmness coefficient,initial gas release rate,and coal porosity,etc.The original data were used as the basis for predicting the danger of coal and gas outburst.(3)The numerical simulation study is used to study the variation of surrounding rock after the protective layer is mined.Combined with the actual situation of the mine,it can be seen from the vertical displacement field of the strike and inclined sections that the vertical displacement of the roof increases with the advancement of the working face,and there are more mining fissures,and the roof rock mass is more affected by the mining activities.Big.However,the displacement of the rock mass of the floor is relatively small,and the distribution of mining fractures is less.The overburden in the mining area mainly shows a downward vertical displacement.Due to the goaf near the upper part,the displacement field of the lower coal and rock body changes obviously in the oblique direction.(4)According to the actual conditions of the six mining areas,three indexes are taken as prediction indicators: gas pressure of the coal seam,gas emission from the working face,and vertical displacement and deformation of the surrounding rock between the protective layer and the protected layer.Model method,select the GM(1,1)model,the metabolic GM(1,1)model,the GM(1,1)residual model,and the GM(1,1)-Markov combination model in the nonlinear scientific gray theory.Simulation calculations and comparison results show that the gray GM(1,1)-Markov combination forecasting model has higher prediction accuracy.Different indicators can be selected and optimized to reduce the measured workload in production activities.After analysis,it is concluded that the 9(8)coal seams that are mined are prominent and dangerous coal seams,and various outburst prevention measures during mining activities are also the key to gas management.(5)Combining the protection layer mining technology and the gas drainage plan design,four gas control plans are proposed for the 1061 working face,and the gray weighted cluster analysis is carried out from the aspects of drilling engineering quantity,construction period and capital investment to seek the most scientific A reasonable gas management plan,and the actual situation and effect test of the engineering application is verified.It can provide scientific and reasonable gas disaster prevention and control technology for similar and prominent mines.