穿层钻孔瓦斯抽采半径效果考察研究

The Observational Study of Effect of Radius of Drilling Hole for Gas Drainage

钻孔间距是影响瓦斯抽放效果的重要因素,钻孔间距过大,在抽放范围内容易形成抽放盲区,达不到消突的目的,钻孔间距过小,容易造成人力、物力的浪费。采用压降法进行瓦斯抽采半径考察,得出瓦斯有效抽放半径结论。通过该项目确定:(1)C23、C25煤层穿层瓦斯抽采钻孔有效有效半径,从而确定我矿井C25煤层顺槽预抽条带钻孔的抽采有效半径;(2)确定需要抽采的各煤层各项瓦斯参数,通过实地测定计算得出。根据得出的各项参数(煤层的透气性系数、瓦斯含量等)计算出理论的瓦斯抽采半径;(3)最后确定实际的瓦斯抽采半径。

The distance between the drilling hole the important factor influence the gas drainage effect,the large distance of drilling hole caneasily cause blind area during gas drainage and cannot reach the aim of gas elimination,the small distance of drilling hole easily wastemanpower and material resources.This thesis use pressure-drop method observe the radius of gas drainage and draw the conclusion of effectiveradius of gas drainage.According to this project find out：（1）The effective radius of gas drainage of C23 and C25 coal seam,then confirm the ef-fective radius of gas drainage of crossheading of C25 coal seam; （2）By practice calculation confirm the each parameters of gas need to extract,according to each of parameters（gas permeability coefficient in coal seam,gas content,etc） calculate the theoretical gas drainage radius;（3） Fi-nally confirm the practice gas drainage radius.