我国煤矿区矿井水污染问题及防控技术体系构建

Mine water drainage pollution in China’s coal mining areas and the construction of prevention and control technical system

煤炭开采必然产生大量的矿井涌水,我国目前的矿井水整体上表现出水质相对较差、水处理成本较高等问题。首先明确了我国典型矿区矿井水水质的主体特征:常规离子是造成矿井水水质差的主要化学组分;矿井水中有毒有害物质占比小,且基本优于地下水Ⅲ类水质量标准。其次,详细探讨了我国矿井水水质形成、演化的几个科学问题,包括不同水文地质结构下物理–化学作用所起的主导作用,时间效应对水质演化的影响,微生物群落结构特征及其与环境因素的相关关系,水动力场–化学场–微生物场–温度场的多场耦合问题等。接着重点介绍矿井水污染防控的技术方法,以减少矿井突(涌)水量和水资源保护为前提,以实现煤–水双资源协调开采、煤炭绿色开采为目标,以矿井水"阻断、减量、保护"为主要防控思路,围绕煤矿区矿井水阻断技术、污染负荷减量技术、污染区修复治理等科学问题展开分析;通过各种现有技术、方法、工艺,最大可能地降低吨煤矿井水处理成本,如采用井下预处理、地面深度处理、超深回灌封贮、生态资源化利用等。最后,提出研发煤矿区地下水及污染物的阻断材料和吸附材料、注浆装备、监测设备、投料设备、原位取样检测设备等,形成我国煤矿区矿井水污染防控技术体系。该技术体系的构建可对煤矿绿色开采、煤矿区深层地下水污染防控、闭坑矿井水污染防控、矿区地下水资源及生态环境保护利用等提供理论及技术支撑。

Mining activities are bound to produce enormous mine water drainage. Mine water in China shows relatively poor water quality and high cost of water treatment and other problems. Firstly, the main characteristics of mine water quality in China’s typical mine areas are clarified in this paper: conventional ions are the main chemical components causing poor mine water quality;mine water has a small proportion of toxic and harmful substances, which is generally better than the quality standard of class Ⅲ groundwater. Secondly, some scientific issues on the formation and evolution of mine water quality are discussed in detail, including the leading role of physical-chemical effects under different hydrogeological structures, the influence of time effect on water quality evolution, the relationship between microbial community structure characteristics and environmental factors, the multi-field coupling of hydrodynamic field, chemical field, microbial field and temperature field. Then, this paper mainly introduces the prevention and control techniques of mine water pollution where on the premise of reducing the amount of water inrush and the protection of water resources, with the goal of realizing the coordinated mining of coal and water resources and the green mining, and the main ideas of "block, reduction and protection" for prevention and control of mine water, scientific issues such as mine water blocking technology, pollution substances reduction technology and pollution area restoration and treatment are analyzed. The cost of coal mine water treatment can be minimized through various existing technologies, methods and processes, such as underground pretreatment, surface in-depth treatment, super deep recharge and storage, ecological resources utilization. Finally, the paper puts forward the development of blocking materials, adsorption materials, grouting equipment, monitoring equipment, feeding equipment, in-situ sampling and detection equipment for groundwater and pollutants in coal mine areas, forming the technical system of mine water pollution prevention and control in coal mine areas. The construction of this technical system provides theoretical and technical support for green mining, the prevention and control of deep groundwater pollution in coal mine areas, the prevention and control of water pollution in closed mines, the protection and utilization of groundwater resources and ecological environment in mine areas.