巨厚充水含水层疏放水层位优化研究

Research on the water drainage layer optimization of extra-thick water-filling aquifer

东胜煤田纳林河矿区营盘壕煤矿煤层埋深大、含水层厚,以往均是将直接充水含水层直罗组含水层视为一完整的统一含水层。矿井在工作面回采前对上覆直罗组含水层进行疏水降压,疏放水量衰减较快、水压降幅大,但采空区涌水量依然较大,疏放水效果与采空区涌水量较大相矛盾。对直罗组含水层垂向岩性特征及富水性特征进行了分析,揭示出直罗组含水层之间存在泥岩及砂质泥岩互层,含水层间呈非连续状态;采用分层抽水试验及井下放水试验、含水层水文动态观测可知,直罗组含水层具有明显的分层性,上下端含水层水位有区别,不同层段含水层之间水力联系微弱,直罗组含水层并非一完整的统一含水层。研究结果可为巨厚砂岩深埋矿区优化疏放水层位、提高疏放水效果提供依据。

Yingpanhao Coal Mine in Nalinhe mining area of Dongsheng Coalfield has a deep coal seam and a thick aquifer.In the past,the direct water filling aquifer of the Zhiluo Formation was considered as a complete and unified aquifer.Before mining,the water drainage and depressurization were conducted at the overlying Zhiluo Formation aquifer,resulting in a rapid decrease in water volume and a large decrease in water pressure,while the amount of water inflow in the goaf was still relatively large,and the drainage effect was contradictory to the large amount of water inflow in the goaf.The vertical lithological and water rich characteristics of the Zhiluo Formation aquifer were analyzed,revealing the presence of interbedded mudstone and sandy mudstone between the aquifers and the discontinuous state between aquifers.By layered pumping tests,underground water discharge tests,and hydrological dynamic observations of aquifers,it was concluded that the Zhiluo Formation aquifer was obviously layered,with differences in water levels between the upper and lower aquifers,and the hydraulic connections between aquifers in different layers were weak,and the Zhiluo Formation aquifer was not a complete unified aquifer.The research results can provide a basis for optimizing the drainage layer and improving the drainage effect in deep buried mining areas with extra-thick sandstone.