The Study Of The Prediction Of The Amount Of The GAS Emission And Its Influencing Factors In Liyazhuang Coal Mine

The gas is the mixture of the harmful gases which released in coal seam, rock stratum, and goaf in the process of coal mining among it, CH4 is the main component, so it is narrowly defined to gas. Gas usually comes from coal seam and it is the chief hazard to coal mining . The hazards of the gas to mine safety normally display of three forms: burst,explosion and asphyxia. Among them gas explosion and gas burst are the most seriously, which do great harmful to mining workers and mine facility.Gas emission quantity is an important factor affected mine safety. In the coal mining, the gas emission from stope face account for 50%～80% of the whole gas emission. It is the chief headstream of the gas emission in coal mine. The gas emission of the working face changes a lot Because of the variation of the coal mine pressure, t he gas-bearing capacity ,the difference of the roof control and production technology. So it is significant to work safety of coal mine in China by means improving the predicted method of stope face gas emission, researching influencing factor of the gas emission and discovery gas emission regular of the stope face.The paper systematically discusses the gas reservoir state, the coal absorption to the gas and the theory of the gas migration in coal seam. Analyzing of the characteristic of the working face, four sources are given: wall methane emission, fallen coal methane emission,goaf methane emission and the close seams methane emission. The paper summarizes the rule of gas emission of coal rib and fallen coal according to collecting, sorting and analyzing a lot of measurement data from site testing and theoretical work. By analyzing and summarizing the existent problems of the predicting method of the gas emission quantity of the working face, the theory of gas flow in coal seam, the regular of gas emission, all sources of gas emission in stope face are separately predict .basis of predicting method of separately, the calculating formula of the gas emission on stope face being suit able the coal mine which gas-bearing capacity is changing because of complex geological structure is given and the measurement method of the needed parameters are given.Finally, the method is applied to predict the stope gas emission of the LiYaZhuang coal mine, the result coincides with the actual measurement approximately. The method can represent the change of the gas emission because of the change of the gas-bearing capacity. It is suitable to the complex geological structure coal mine including the common coal mine.According to the production fact of the LiYaZhuang coal mine, the rule of the stope gas emission and the influencing factor of the gas emission are given in this paper,the relationship of output,air quantity,footage and water spray are also studied. It is very usful to prevent the gas disaster and ensure the coal mine safety production.