煤层底板分阶段疏水降压水害防控方法

Water disaster prevention and control method of coal floor of stepwise water drainage and depressurization

为有效防控侏罗纪煤田深部煤层底板高承压含水层砂岩水害,基于井田单斜构造特征,利用放水试验与地下水流数值模型,构建一种煤层底板高承压砂岩含水层分阶段疏水降压的水害防控方法。结果表明:煤层底板高承压砂岩含水层采用分阶段疏水降压水害防控方法,可有效避免疏放水钻孔揭露高承压含水层,将含水层水位疏降至安全水位以下,达到理想的水害防控效果。利用单孔和多孔放水试验数据识别和校验地下水流数值模型,并定量预测疏放水量、疏放时间和总疏放水量,可实现煤层底板高承压含水层砂岩水害的精准防控。

In order to effectively prevent and control the water disaster from the high confined aquifer below the deep coal floor seam of Jurassic coalfield,based on the inclined structure characteristics of the coalfield,by the dewatering test and numerical model of groundwater flow,a kind of water disaster prevention and control thought for high confined sandstone aquifer below the coal seam was constructed.The research shows that the water disaster prevention and control method of coal floor of stepwise water drainage and depressurization can effectively avoid exposing high confined aquifer by drainage borehole,and reduce the water level of the aquifer to below the safe water level,thus achieving the ideal effect of water disaster prevention and control.The numerical model of groundwater was identified and verified by single and multiple boreholes dewatering test data,and drainage amount,drainage time and total drainage amount of water discharged were predicted quantitatively,so as to realize the precise prevention and control of water disaster from high confined aquifer sandstone aquifer below the coal seam.