突出煤层瓦斯抽采钻孔有效半径与孔壁变形关系研究  

Study on relation between effective drainage radius of borehole and drilling wall deformation in outburst coal seam

作　　者：魏杰[1] 吴世跃[1] 王飞[1] 柴琳[1] WEI Jie;WU Shi-yue;WANG Fei;CHAI Lin(College of Mining Engineering, Taiyuan University of Technology, Taiyuan 030024, Chin)

机构地区：[1]太原理工大学矿业工程学院,山西太原030024

出　　处：《煤炭工程》2018年第7期87-91,共5页Coal Engineering

摘　　要：为了能够更加准确、合理地确定钻孔有效抽采半径,以钻孔孔壁内煤体的渗透率为主要研究对象,结合孔壁煤体应力场弹塑性分析及渗流场分析结果,构建了综合考虑有效应力变化、煤基质解吸收缩效应的渗透率动态模型。在此基础上运用多孔介质渗流的基本理论,修正了抽采钻孔的瓦斯渗流微分方程,并以沙曲矿4号煤层为例,运用Comsol Multiphysics软件进行数值模拟,得到了煤层渗透率和瓦斯压力的分布规律,并根据防突规定,以瓦斯压力0.74MPa为临界值,确定了模拟条件下180d时钻孔有效抽采半径为1.65m,该结果可为实际生产提供理论参考。In order to determine the effective drainage radius of borehole accurately and reasonably, the permeability of the coal around the borehole is taken as the main object of study, combining with the results of comprehensive analysis of the stress field Elasto-plastic and methane seepage field around the borehole, the dynamic model of coal permeability is established, which considers the effective stress in the mining process and the desorption and contraction of the coal matrix. Based on the basic theory of porous medium seepage, the differential equation of methane seepage in pumping boreholes is established, numerical simulation is performed using Comsol Multiphysics software, taking Shaqu Mine No. 4 coal seam as an example, the variation law of coal seam permeability and gas pressure are obtained respectively, according to the relevant provisions of extraction standards, and taking the gas pressure 0. 74MPa as the critical value, it is determined that the effective drainage radius of the borehole under the simulated condition of 180 days is 1.65m. The results can provide reference for the actual production.

关 键 词：突出煤层 瓦斯抽采 有效抽采半径 渗透率 

分 类 号：TD713.3[矿业工程—矿井通风与安全]