瓦斯抽采钻孔护孔用割缝筛管抗堵性研究

Study on Anti-clogging Performance of Screen Pipe for Holes Protection in Gas Drainage Boreholes

为了验证常规圆孔筛管和割缝筛管在瓦斯抽采过程中煤粉抗堵性上的差异,利用PFC3D离散元分析软件分析了常规圆孔筛管和割缝筛管的煤粉通过性能,根据模拟结果优选了割缝参数,并在阳泉矿区寺家庄煤矿15117工作面回风巷15号煤层中进行了常规圆孔筛管和3种不同割缝参数的割缝筛管的瓦斯抽采试验。数值模拟结果表明:总体趋势上,割缝筛管的煤粉通过量要小于圆孔筛管,对于割缝筛管,割缝宽度对煤粉通过量的影响要大于割缝长度;现场试验表明:抽采试验中采用割缝筛管护孔的抽采孔平均瓦斯流量和瓦斯浓度分别是常规圆孔筛管护孔抽采孔的6倍和3.8倍,验证了煤粉通过量越小的筛管,其抗堵性能越优,瓦斯抽采效果也越好。

In order to verify the difference between the round-hole screen pipe and the slotted screen pipe in the gas drainage process,this paper analyzes the passing performance of the conventional round-hole screen pipes and the slotted screen pipes with PFC3 Ddiscrete element analysis software.According to the simulation results,the slotting parameters are optimized,the gas drainage tests of the round-hole screen pipe and 3 kinds of the slotted screen pipe with different slotting parameters were carried out in coal seam 15# of 15117 working face in Yangquan mining area.The results of numerical simulation show that the volume of passed particles through the slotted screen pipes is less than that through the round-hole screen pipes;and for slotted screens,the effect of the slotted width on the volume of passed particles is greater than the slotted length.The field test shows that the average gas flow and gas concentration of the slotted screen pipe are 6 times and 3.8 times that of the round-hole screen pipe respectively,it proves that the smaller the volume of passed particles is,the better the anti-clogging performance is,and the better the gas drainage effect is.