顺层钻孔瓦斯抽采有效半径研究

Study on effective radius of gas drainage in bedding drilling

为高效抽采某矿3号煤层瓦斯,需要合理布置抽采钻孔,而合理的钻孔间距依据有效抽采半径来确定。本文通过比较分析瓦斯压力降低法、示踪气体法、数值模拟法和瓦斯储量法的优缺点,确立了基于瓦斯储量法测定钻孔有效抽采半径,并采用COMSOL Multiphysics对有效抽采半径进行了模拟,结果表明:两种方法测定结果基本相同。预抽60d,有效抽采半径为1.95m;预抽90d,有效抽采半径为2.37m;预抽180 d,有效抽采半径为2.80m。

In order to make gas drainage more efficient ,it is necessary to plan reasonable drainage holes, while the distance of two drainage holes depends on effective extraction radius. By analyzing the reduction of gas pressure and gas reserves, using tracer gas method and numerical simulation, effective drainage radius has been confirmed in this paper. At the same time, effective drain- age radius has been simulated for recalculating by using COMSOL Muhiphysics. The conclusion has shown that the results based on two different kinds of measuring method are essentially the same. Pre -drainaging for 60 days,90 days and 180 days the effective extraction radius is 1.95m,2.37m and 2.80m.