Prediction Of Gas Emission From Multiple Sources In Large Mining Height And Extra Long Working Face

As the "first killer" of coal mine safety production,gas seriously restricts the safe and efficient production of coal mines.Therefore,it is important to carry out research on the law of gas distribution at the working face,statistically analyse the sources and amount of gas gushing out,and summarise the prediction model of gas gushing out for the management of gas at the working face.This paper mainly takes the 12322 working face of Wangjialing coal mine as the research object,and analyses the law of gas distribution,gas gushing sources and gas gushing quantity of this working face,and predicts the gas gushing quantity of the working face by combining factor analysis method,BP neural network and Kalman filter,and obtains the following conclusions.The coal seam gas content No.2 was determined by direct method,the maximum amount of desorption was 1.97 ml/g,the minimum was 1.30 ml/g,and the maximum gas content was 3.64m~3/t and the minimum value was 2.94 m~3/t,average 3.15m~3/t,through qualitative and quantitative analysis,the geological factors and so on have an impact on the overall trend of coal seam gas content,but the degree of influence is different,the results show that coal seam buried depth is the main factor affecting gas storage.Using the unit analysis method to measure the distribution of working surface gas in three dimensions,the proportion of gas surge of the working surface is obtained through theoretical analysis and calculation:75.17 percent of coal wall and 24.83 percent of the mining area.And the coal mining surface gas surge is divided into five sources.Among them,the total amount of absolute gas surge of the work surface is 11.15m~3/min,and the gas surge from the mining area accounts for more than half of the total surge.According to the characteristics of coal seam gas content of a mine No.2 in Shanxi Province,as well as the normal production rate of the mine according to the design year,the source prediction method is used to predict the gas surge volume of the coal seam No.2 coal seam under different buried depth conditions The minimum prediction error was 8.6%,the minimum prediction error was 0.21%,the average prediction error was 2.81%,the average error was 30.62%lower than that of the direct BP neural network prediction,and the prediction value obtained by factor analysis and BP-ANN-Kalman filter prediction was closest to the real value.Through the research on the gas occurrence law and gas emission source and law of 12322 working face in a mine in Shanxi Province,the research results provide the basis for the prevention and control of gas accidents,have certain practical significance,and ensure the safe production of the mine.It also provides a theoretical basis and guidance for the construction and gas control of nearby mines.