大垂距双层采空区流场平衡控制技术

Control Technology of Flow Field Balance in Double-layer Goaf with Large Vertical Distance

为了解决大垂距火区下综放面均压通风防治上部火区有害气体下泄时将采空区瓦斯压入火区引发次生灾害的问题,采用理论研究的方法,对大垂距双层采空区流场平衡的控制条件进行分析,确定了双层采空区流场平衡的安全调节区间。在同忻煤矿西8101工作面进行应用,结果表明:当连接双层采空区的U型水柱计压差满足(350+0.016l,538+0.016l),l∈(85,1 600)时,工作面上隅角CO体积分数在回采期间始终保持在24×10-6以下,有效地保障工作面的安全回采。

In order to solve problem of the secondary disaster caused by the goaf gas pressed into the fire area when the method of pressure balancing ventilation is used to prevent the harmful gas of upper fire area discharge in the fully mechanized caving surface under large vertical distance fire area, by using the method of theoretical research, the control condition of flow field balance in double-layer goaf with large vertical distance is analyzed, and the safe adjustment interval of flow field balance in double-layer goaf is determined. It is applied in the western 8101 working face of Tongxin Coal Mine, and the results show that,when the gauge pressure difference of U-shaped water column connecting the double-layer goaf meets(350+0.016 l,538+0.016 l),l ∈(85,1 600), the volume fraction of CO at the corner of the working face is always kept below 24 ×10^-6 during the mining period, which effectively guarantees the safe mining of the working face.