我国大水矿山侧向帷幕截水技术及水资源保护效果研究

Lateral curtain interception technology and water conservation effect in groundwater abundant mines of China

我国矿山种类多、数量多,涵盖煤炭、冶金、有色金属、化工等,大部分矿山采用疏干排水方式控制地下水,部分大水矿山矿井每天疏排水量数万立方米到数十万立方米,疏干排水引发地下水位下降、水资源枯竭、岩溶塌陷和地面沉降、地表水污染、地下水环境恶化等问题。为解决大水矿山的安全开采和水资源浪费问题,自20世纪60年代开始进行矿山截水帷幕技术研究,经过近60 a的发展,由单一的地面直钻孔注浆发展为地面定向钻孔注浆、井下钻孔注浆、井上下联合钻孔注浆、桩排、连续墙、防渗膜等多种截水帷幕技术,先后在80余座矿山成功应用了半封闭式、封闭式、落底式和悬挂式截水帷幕,截水率大多在60%以上,帷幕外侧水位显著抬升,取得非常好的应用效果,保护了矿山水资源和矿区生态环境。选取金属矿岩溶裂隙水全封闭帷幕、煤矿基岩落底式注浆帷幕、松散层与岩溶地层定向水平孔注浆帷幕、松散层防渗膜落底式帷幕等4种典型截水帷幕案例进行了详细阐述,分析了典型截水帷幕案例的截水技术及水资源保护效果,有效截水率均在75%以上。基于帷幕截水技术发展趋势,提出了大水矿山侧向帷幕截水技术将朝着松散层侧向无接头连续截水帷幕、基岩侧向截水帷幕定向扩散注浆、低渗厚基层侧向截水帷幕等技术方向发展,践行“绿水青山就是金山银山”理念,保护矿山地下水资源,实现矿山保水、保生态、减损、绿色开采。

There are many types and numbers of mines in China,covering coal,metallurgy,non-ferrous metals,chemical industry and so on.Most of the mines use dewatering and drainage to control groundwater,and some of the water abundant mines have tens of thousands of m3 to hundreds of thousands of m3 of mine drainage per day,which causes the problems of declining groundwater level,water resources depletion,karst collapse and ground subsidence,surface water pollution,and deterioration of groundwater environment.In order to solve the problem of safe mining and water waste in water abundant mines,research on mine water cut-off curtain technology has been carried out since 1960 s,and after nearly 60 years of development,it has developed from single ground straight drilling and grouting to various water cut-off curtain technologies such as ground directional drilling and grouting,downhole drilling and grouting,combined drilling and grouting up and down the shaft,row of piles,continuous wall and seepage control membrane,etc.In more than 80 mines,semi-closed,closed,drop-bottom and suspended water interception curtains have been successfully applied,with water interception rate mostly above 60%and water level on the outside of the curtain significantly raised,achieving very good application results and protecting mine water resources and mine ecological environment.Four typical water interception curtain cases,such as metal mine karst fissure water fully closed curtain,coal mine bedrock drop bottom type slurry curtain,loose layer and karst stratum directional horizontal hole slurry cur-tain,loose layer impermeable membrane drop bottom type curtain,were selected for detailed elaboration,and the water interception tech-nology and water resource protection effect of typical water interception curtain cases were analyzed,and the effective water interception rate was above 75%.Based on the development trend of curtain water interception technology,it is proposed that the technologies of con-tinuous jointless water curtain in the lateral direction of loose layer,directional diffusion grouting in the lateral water curtain of bedrock,and lateral water curtain in the thick grass-roots level with low permeability are future directions,so as to practice the concept of“Green Mountains Are Mountains of Gold”,to protect the groundwater resources of mine,and to realize water conservation,ecology conservation,loss reduction and green mining.