煤层注水的水气驱替理论研究  

The Study on the theory of water and gas replacing during water injection into coal seams

作　　者：宋维源[1] 李大广[1] 章梦涛[1] 潘一山[1] 孙超[1] 

机构地区：[1]辽宁工程技术大学力学与工程科学系,辽宁阜新123000

出　　处：《中国地质灾害与防治学报》2006年第2期147-150,共4页The Chinese Journal of Geological Hazard and Control

摘　　要：煤层注水是世界上煤矿矿井防治冲击地压的首选措施。而注水时间、流量、压力等注水工艺参数选择是决定注水防治冲击地压效果的关键。煤层注水过程中水在煤层中渗流的规律是选择注水工艺参数的理论依据。由于煤层孔隙、裂隙中充满气体,煤层注水实际上是水替代气的水驱气的渗流过程。但迄今为止的研究均视为水在煤体中渗流的研究。与实际相距甚远。论文首先分析了煤层注水防治冲击地压的机理,注水使得煤层软化,达到峰值强度后煤体抵抗变形能力随应变降低的幅度减小,即强度后应力-应变曲线变缓。然后根据煤层注水是水驱气过程,将煤层注水视为水气驱替的有动界面的渗流问题研究。将煤层视为各向同性的孔隙介质,分别按照水驱气由钻孔径向周边流动的平面径向流和由钻孔沿煤层平行流动的平面平行流两种情况,建立了水驱气的微分方程,给出了定解条件,并进行求解,得到了不同时间水锋面到达的位置即水注满煤层孔隙的范围。从而可以根据需要注水的范围求出需要提前的注水时间和注水量。为煤层注水预防冲击地压的工艺参数选择提供了科学依据和理论支撑。The first choice for precaution of pressure bump is water injection into coal seames. The effect of the prevention of the pressure bump is decided by the technological parameters which include the injection time, influx and pressure. During the water injection in coal seams, the fluidal rule is the basis in determining technological parameter. Since the coal seams crack and apertures overflowed by the gas, the water injection in coal seams is the procedure that the water replaces the gas, but most of the studies subjects are the water flowing through the coal seams now, and this is far away from reality. In this paper the mechanics is analysed firstly, which is about the prevention and care of water injection in coal seams, the injection emolliates the coal seams, when reaching the maximal intensity numerical number, the capability that the coal resists distortion following the deformation fall falls down. Since the water injection in coal seams is the course that water drives gas, are regarded the water injection in the coal seams is regarded as the fluidal question that water drives the gas. The coal seams as isotropous vantage medium. According to the surface redial flow and surface parallel flow we deduce the differential equation about water driving gas, and then according the terminal conditions undo the equations would be solved. We can get the positions of moving surfacing under the different times. And then we can decide the water injection time and the water quantity in advance according to the dimension of water injection.

关 键 词：冲击地压 煤层注水 平面径向流 平面平行流 动界面 躯替 提前注水时间 

分 类 号：TD315[矿业工程—矿井建设]