Abstract： In order to determine the influencing factors of gas extraction radius of bedding boreholes and the spacing of boreholes, a multi-physical coupling numerical model of gas migration was established based on the occurrence conditions of M12 coal seam in a mine in Guizhou. The effect of single factor on the extraction radius was analyzed by changing the single factor value, and the extraction radius of single borehole and multi-borehole was simulated. The results show that when the extraction time reaches 150 d, the extraction radius is calculated to be 2.2 m by the flow method. Through simulation analysis, it is found that the extraction radius increases with the extension of time, increases with the increase of borehole diameter, increases with the increase of initial permeability of coal seam, and the increase amplitude increases with the extension of extraction time, while the negative pressure of extraction has little effect on the effective extraction radius. According to the numerical simulation analysis, when the extraction time reaches 150 d, the simulation result of the extraction radius is 2.1 m. Affected by the superposition of adjacent boreholes, the extraction radius of multiple boreholes is larger than that of a single borehole. It is about 1.76 times of the extraction radius of single borehole. The research results provide a theoretical basis for the reasonable arrangement of extraction boreholes on site.
刘玉峰. 顺层钻孔有效抽采半径影响因素及布孔间距研究[J]. 煤炭与化工, 2024, 47(2): 115-119.
Liu Yufeng. Study on the influencing factors of effective extraction radius and hole spacing of bedding boreholes. CCI, 2024, 47(2): 115-119.
