Abstract: In order to grasp the gas occurrence of A5 coal seam in Sikeshu No.2 well and the law of gas emission in working face under different production conditions, the gas composition of A5 coal seam in Sikeshu No.2 well was tested to determine the gas zoning, and the original gas pressure and gas content were measured. The effects of working face production and air volume on absolute gas emission, gas concentration in upper corner and gas concentration in return air flow were investigated on site. The results show that the gas zoning of A5 coal seam belongs to N2-CH4 zone, the maximum original gas pressure is 0.62 MPa, and the maximum gas content is 2.72 m3/t. The gas occurrence in the region is unstable and the difference is large. The absolute gas emission from the working face and the gas concentration in the upper corner generally show a law of increasing with the increase of production. The absolute gas emission from the working face is 5 m3/min. The corresponding class output is about 600 t. The larger the output, the more divergent the gas concentration distribution in the upper corner, and the more difficult it is to control. The gas concentration of the return air flow increases with the increase of the class output, but the increase is not obvious when it is increased from 600 t to about 900 t. The absolute gas emission of the working face is very different, but the air volume does not affect it.
王正帅1,杨 周2. 四棵树二号井煤层瓦斯赋存及涌出规律研究[J]. 煤炭与化工, 2023, 46(9): 96-99.
Wang Zhengshuai 1, Yang Zhou 2. Study on the law of coal seam gas occurrence and emission in Sikeshu No.2 well. CCI, 2023, 46(9): 96-99.