综放工作面顶板随采式专用排瓦斯巷布置研究

On the specialized gas drainage lane layout of the mining direction style in the roof of the fully mechanized caving face

确定合理的专用排瓦斯巷参数是确保能否高效治理综放工作面瓦斯积聚及上隅角瓦斯超限现象的关键。结合五阳煤矿7605工作面的实际情况,采用瓦斯运移规律、矿压理论、矿井通风等理论及FLAC3D数值模拟软件,对专用排瓦斯巷的合理层位、距离回风巷的水平距离、巷道断面面积等参数进行了研究。结果表明,专用排瓦斯巷适合布置在岩层垮落带的中下部,距离回风巷的水平距离受巷道等效半径影响,巷道断面面积由通风能力和掘进工程量决定,7605工作面专用排瓦斯巷的3个参数分别为距煤层顶板2.65~6.75 m、距离回风巷水平距离约15 m、巷道断面面积7 m^2。现场应用表明,工作面回采期间瓦斯体积分数维持在0.3%左右,上隅角瓦斯体积分数未发生超限,瓦排巷与工作面连通顺畅,瓦斯治理效果显著。

This paper is aimed at working out the most reasonable parameters for the special-purposed gas drainage lane,which can be regarded as the key link to solve the upper corner gas overflow and the over-gas accumulation. For the research purpose,we have first of all studied the gas-layer location,the horizontal distance of the gas layer to the return airway,as well as the lane section size. In accordance with the reasonable parameters of the said gas drainage lane,we have studied the theories of the gas moving regularity,the mining pressure and the coal seam control,as well as that of the mining ventilation control methods,through which we have established a calculation method for determining all the parameters for the aforementioned gas drainage lanes.And,then,we have combined the actual situation we have gained with the actual situation in the working face No. 7605,of Wuyang coal mine. At the same time,we have simulated the mutual influence between the roadways of different horizontal distances（ 5 m,10 m,15 m,20 m） from the specialized gas drainage lane to the ventilation back-airways by FLAC3 D numerical simulation software. And,finally,we have done an analysis of the appropriate sections of the specialized gas drainage lanes in accordance with the initial mining stage air duct model in the above mentioned working face. The above said analysis has helped us to find that the reasonable layer position of the drainage lane should be located in the mid-lower section of the rock-caving zone,whose horizontal distance to the return airway tends to be influenced by the equivalent radius of the roadways,whose section size has to be determined by the ventilation power and the amount of waste rocks to be excavated. Thus,the three parameters of the working face we have worked out of No. 7605 workface should be： 2. 65-6. 75 m to the coal seam roof,and 15 m horizontal distance to the return airway,with its section size being about 7 m2. What is more,the field application shows that,the gas concentration in the working face has to be kept on at around 0. 3%,with the upper corner gas concentration not overrun,and the dedicated gas drainage lane linked with the working face smoothly,so as to make the gas control effect remarkable.