School of Mining and Coal, Inner Mongolia University of Science and Technology
There is a complex coupling relationship between spontaneous combustion of coal and gas explosion in goaf, which is easy to interlock and affect the safety of coal mine production. Taking 1012 working face of a mine in Wuhai as the research background, it is proposed to inject N2 into goaf to reduce the occurrence of accidents. In order to explore reasonable nitrogen injection schemes, FLUENT simulation technology was used to analyze the distribution of oxygen concentration and gas concentration fields in goaf under different nitrogen injection schemes, and determine the areas of various danger zones. Then, the tunnel engineering safety evaluation method was used to determine the corresponding regional coefficients, and the risk degree scores corresponding to different nitrogen injection schemes were calculated on the basis of the two. origin was used to calculate its coupling function. According to its function, the optimal nitrogen injection scheme was determined that the nitrogen injection amount was 379m3/h, and the nitrogen injection position was located at 58m of the working face. Finally, the engineering field measurement of the scheme proved that its control effect was good. The results show that: In this paper, the oxygen concentration of the goaf oxidation heating zone is used to determine the reasonable nitrogen injection amount of 379m3/h. At this nitrogen injection amount, as the nitrogen injection position moves to the inside of the goaf, the risk degree fraction decreases first and then increases. The optimal nitrogen injection location is determined to be the inside of the goaf inlet wind side 58m away from the working face, and the research results can provide reference for similar projects.