采动区瓦斯地面井抽采影响范围及流量变化规律研究

为解决煤矿采动区地面井布置间距目前大多依靠工程经验获得而缺乏科学理论根据的问题,采用COMSOL Multiphysics数值模拟软件建立了计算采动区地面井抽采瓦斯纯流量和瓦斯压力分布的三维数值模型。以岳城煤矿相关物性参数计算出符合实际情况的煤岩渗透率、孔隙率及瓦斯质量源项,以此为基础进行数值模拟。模拟分析结果表明,在数值模拟中地面井瓦斯抽采影响半径为65 m,地面井抽采瓦斯纯流量变化规律呈“单峰拖长尾”形态特点。若要实现采动区瓦斯抽采全覆盖,则在实际工程应用中地面井的间距应取130 m以上。研究结果对优化采动区地面井布置具有指导意义。

Study on the law of drainage range and flow of surface well in mining area

The spacing of surface wells in the mining area of coal mines mostly depends on engineering experience and lacks scientific theoretical basis at present.In order to solve this problem,the numerical simulation software of COMSOL Multiphysics was used to establish a three-dimensional numerical model to calculate the scalar gas drainage and gas concentration distribution in goaf of surface well drainage in mining area.Based on the related physical property parameters of Yuecheng Coal Mine,the coal and rock permeability,porosity and gas quality source terms that in accordance with the actual conditions were calculated,and the numerical simulation was carried out on this basis.The simulation analysis results show that:in the numerical simulation,the influence radius of surface well gas extraction is 65 m,the variation of scalar gas drainage from surface well is characterized by“single peak and long tail”.If the full coverage of gas drainage in mining area is to be realized,the spacing of surface wells should be more than 130 m in practical engineering application.The research results have guiding significance for optimizing the surface well layout in mining area.