深埋侏罗系煤层顶板水害源头防控关键技术

为解决目前蒙陕矿区深部侏罗系矿井采后采场落地水量大、煤水混杂,以及上部煤层距离强含水层较近,无法安全掘进与回采等一系列问题,提出了深埋侏罗系煤层顶板水害源头防控关键技术。应用沉积控水规律,分析了含(隔)水层在平面与剖面的空间展布规律与含水层富水性分布规律,在此基础上,针对煤层厚度变化较大、顶板含(隔)水层交互成层的特征,通过构建含有沉积环境影响指数、砂岩厚度、岩芯采取率、单位涌水量、渗透系数与导水裂隙带发育高度6个指标在内的评价指标体系,提出了符合深部侏罗系矿井水文地质特征的矿井涌(突)水风险分区评价方法,进而根据"断源截流、集中疏排、源头预防、超前治理"的防治水思路,提出了"上行开采低位截流"、"工作面单侧截流"、"工作面双侧截流"与"工作面方向调整截流"4种地下水截流治理模式,最后以蒙陕矿区的门克庆矿井和母杜柴登矿井进行实例分析。应用结果表明:①直罗组一段砂岩含水层主要为河道相沉积,砂体的空间连续性较好,是深部侏罗系矿井的主要充水含水层;②门克庆矿井首采区3~(-1)煤顶板涌(突)水危险区主要分布在研究区的南部,呈东西向条带状展布,与实际情况较为吻合;③根据门克庆矿井首采区涌(突)水危险性分布规律,应用了"工作面单侧截流"与"上行开采低位截流"两种治理模式并分析了其在实际工程中的应用效果。深部侏罗系矿井水害防治作为一个复杂的系统工程,以源头防控为重点的系统防治技术体系仍是深部侏罗系矿井水害防治需要重点攻关的研究方向。

Key technologies for prevention and control of roof water disaster at sources in deep Jurassic seams

A series of problems,such as the large amount of water inflow,the coal water mixing problems after mining,and unsafe heading and mining due to the close distance between upper seam and strong aquifer,exist in the deep mining areas of Shaanxi Inner Mongolia,China.To solve these problems,this study puts forward the key technologies for prevention and control of roof water disaster at sources in deep Jurassic seams.The spatial distribution in both the plane and section of aquifers (aquicludes) and water abundance distribution of aquifers are analyzed by employing the law of groundwater controlled by geological sedimentary.On this basis,in view of the characteristics of large coal seam thickness variation and the interaction of roof aquifers and aquicludes,a zoning evaluation method of water inrush risk in accordance with the hydrogeological characteristics of deep Jurassic mine is proposed by constructing an evaluation index system composed of sedimentary environmental impact index,sandstone thickness,core recovery,unit inflow,permeability coefficient and the height of water flowing fractured zone.Then,according to the water prevention and control proposal of “intercepting from the source,centralized drainage,source prevention and advanced governance”,four regional closure optimization models composed of upward mining and low flow closure,working face unilateral closure,working face bilateral closure and working face direction adjustment closure mode are determined.Finally,a case study at Mengkeqing Mine and Muduchaideng Mine in Shaanxi Inner Mongolia mining area is carried out.The application results show that:① The sandstone aquifer in the Member 1 of Zhiluo Formation is mainly channel sediments,and the sand body has good spatial continuity,which is the main water filled aquifer in the deep Jurassic mine.② The dangerous water inrush areas of the No.3 1 coal roof aquifer are mainly distributed in the south of the first mining areas in Mengkeqing Mine,showing an east west strip pattern,which is consistent with the actual situation.③ According to the evaluation results of water inrush risk in the first mining areas of Menkeqing Mine,two modes composed of working face unilateral closure,upward mining and low flow closure are applied,and the application effects in practical projects are analyzed.System establishment of source prevention and control technologies will still be the key research direction in deep Jurassic mines.