Study on the reasonable stratum of high-drainage roadway with roof strike of fully-mechanized working face in Sijiazhuang Mine
ZHU Hongqing,HUO Yujia,FANG Shuhao,GUO Jinlin
阳煤集团寺家庄矿15106综采工作面瓦斯涌出量较大且具有突出危险性,针对该工作面上隅角瓦斯易超限的难题,基于工作面上覆岩层破坏的“O”型圈理论,提出了沿走向在顶板布置高抽巷进行瓦斯抽采的方法。为了探究高抽巷布置的最佳区域,首先应用理论计算及材料相似模拟的方法,得到采空区垮落带高度为0~20 m,裂隙带高度为20~60 m,弯曲下沉带高度为60 m以上;“O”型圈的导气裂隙圈在采动侧长为20 m;沿走向方向,开切眼侧破断角基本稳定在60°,回采侧破断角在43°~68°处波动,平均55°;当工作面推进距离与工作面长度相同时,沿倾向方向进风巷和回风巷破断角均为58°。应用Fluent软件分别模拟高抽巷与煤层顶板垂距为20、30、40 m,与回风巷内错距为30、40、50 m时的抽采效果,结果表明:高抽巷垂距为30 m、内错距40 m时,高抽巷内瓦斯体积分数最高,为21.2%,上隅角瓦斯体积分数最低,为0.54%。将试验所得方案应用于现场实践后,在回采初期,由于大裂隙尚未形成,上隅角瓦斯体积分数存在超限危险,随着工作面的推进,风排瓦斯量逐渐减小,高抽巷抽采瓦斯量逐渐升高;在进入正常抽采期后,上隅角瓦斯体积分数平均值约为0.6%,与模拟所得结果基本相符,该方案能够大幅缓解风排瓦斯的压力,有效解决上隅角瓦斯超限的问题。
The gas emission of No.15106 working face of Sijiazhuang Mine of Yangquan Coal Group is relatively large and has outburst hazard. Aiming at the problem that gas at the upper corner of the working face is easy to exceed the limit, based on the "O" ring theory of overburden failure on the working face, a method of arranging high-drainage roadways on the roof along the strike for gas drainage is proposed. In order to explore the best area of layout of high-drainage roadways, first of all, theoretical calculations and material similarity simulation methods are used to obtain that the height of goaf zone is 0~20 m and the height of fracture zone is 20~60 m, the height of bending subsidence zone is more than 60 m. The range of “O” ring separated layer fracture zone on the mining side is 0~20 m.Along strike direction, the fracture angle of the open cut side is basically stable at 60°, and the fracture angle of the stoping side is 43°~68°with an average of 55°, when the advancing distance of the working face is the same as the length, the breaking angle of the inlet and return air roadways along the inclined direction are both 58°.Fluent software is used to simulate the extraction effect when the vertical distance between the high drainage roadway and the coal roof is 20, 30, 40 m, and the staggered distance from the return airway is 30, 40, 50 m. The results show that when the vertical distance of the high extraction roadway is 30 m, and the horizontal distance is 40 m, the gas volume fraction in the high-drawing lane is the highest, 21.2%, and the upper corner gas volume fraction is the lowest, 0.54%.. After the program obtained from the test is applied to field practice, in the early stage of mining, the gas volume fraction in the upper corner has the risk of exceeding the limit due to the large fissures that have not yet formed. With the advance of the working face, the amount of gas discharged by the air will gradually decrease, and the amount of gas extracted by the high extraction roadway will gradually increase. After entering the normal extraction period, the average value of gas concentration in the upper corner is about 0.6%, which is basically consistent with the simulation results. The scheme can greatly relieve the pressure of air exhaust gas and effectively solve the problem of gas overrun at the upper corner
upper corner;"O" ring;gas overrun; reasonable level of high drainage roadway
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会