Abstract: In this paper, taking coal face 62114 in Xinzhuangzi mine, Huainan, as the engineering example, we analyzed the gas emission laws of the coal mining in the closed distance upper protective seam, and proposed the corresponding gas control measures. The results show that, 1) Under the mining disturbance of the upper protective seam, the underlying coal/rock strata can be divided into floor heave fracture zone and floor heave deformation zone in the mining influence area, and the lower protected seams under the floor heave fracture zone have the migration trends to the goaf of protective seam. 2) Y model ventilation can be used to solve gas accumulation and overflow in the upper corner of the face mining in the closed distance upper protective seam. 3) In principle, the spacing of penetrating boreholes in the lower protected seams should be less than or equal to 1 times of the seam spacing, which can just effectively prevent the pressure-relief gas of protected seams flowing into the working face of protective seam. Finally, the gas extraction results of coal face mining in the closed distance upper protective seam of Xinzhuangzi mine were analyzed.

Key words:  closed distance coal seam group, upper protective layer mining, gas emission, gas control