煤矿采空区瓦斯运移机理及规律研究

Mechanism and Rule Study on the Gas Movement in Goaf

在对煤矿瓦斯涌出影响因素分析研究的基础上,对采空区瓦斯来源及运移规律进行了详细的分析研究。研究指出:采空区瓦斯主要来源于开采层及其邻近煤岩层,在压力梯度的作用下,会向采空方向流动;在一定空间范围内,采空区瓦斯压力与时间及距离服从负指数关系。只要有压力梯度的存在,煤体瓦斯就会不断向外流动涌出;瓦斯涌出速度随时间呈负指数关系迅速降低。由于采空区"三带"的形成是一个动态的长时的过程,"裂隙带"瓦斯涌出通常会滞后于"冒落带"瓦斯涌出。该研究对煤矿采空区瓦斯治理具有重要的指导意义和价值。

On the basis of factor analysis on gas effusion in coal mine, detailed study on the origination and movement rule of gas in goaf was carried out. The study demonstrated that gas in goaf originates mainly from coal bed being mined and adjacent coal or rock bed. It can flow or effuse into the goaf under pressure gradient. There exists a negative power relationship between the gas pressure, time and the distance away from the surface wall in the goaf. It is also true for effusion velocity of the gas and the effusion velocity can decrease rapidly with time. As ＂three bands＂ formation is a dynastic long process, gas in ＂fissure band＂ often lag after that in ＂caving band＂. The study is significant for gas control in goaf.