乡宁矿区2号煤层涌水水源水化学特征分析

Analysis on Chemical Characteristics of Gushing Water Source of No. 2 Coal Seam in Xiangning Mining Area

摘要: 在煤矿开采过程中，准确快速地掌握地下水化学特征，对矿井防治水具有重要指导意义。基于58份乡宁矿区某矿二号煤层涌水水源的水质分析资料(离子含量、TDS、pH值)，利用Piper三线图法研究了老空水和砂岩裂隙水的水质类型特征，并利用两水源各离子浓度变化柱状图，对比分析了两种涌水水源之间异同特征。研究结果表明：老空水的水质类型为Na-HCO₃•SO₄型，砂岩裂隙水为Na-HCO₃•SO₄-Ca•Mg型，二者均显现微弱碱性，且二者的TDS很接近；老空水中各离子组分含量分布差异性明显高于砂岩裂隙水，在各离子中，除HCO₃^-、Na⁺ + K⁺含量明显大于砂岩裂隙水外，其余离子(SO₄^2-、Ca²⁺、Cl⁻、Mg²⁺、CO₃^2-)含量均小于砂岩裂隙水；且两水源中HCO₃^-、Na⁺ + K⁺、SO₄^2-三种离子均为含量最高的离子。老空水中 含量高，SO₄^2-含量低，pH值呈弱碱性，TDS略高于砂岩裂隙水，均表明矿井老空水滞留时间较短，补给通道较通畅。可见，矿井防治老空水的方向应为查明老空水补给通道和源头，从根本上遏制老空水害。研究结论可作为乡宁矿区研究区涌水水源快速识别的有效依据。

Abstract: In the process of coal mining, it is of great guiding significance to grasp the chemical characteristics of underground water accurately and quickly. Based on 58 water quality analysis data (Ion content, TDS, pH value) of the gushing water source of No. 2 coal seam of a coal mine in Xiangning Mining area, Piper three-plot method was used to study the water quality type characteristics of goaf water and sandstone fissure water, and the differences and similarities between the two kinds of gushing water sources were compared and analyzed by using the histogram of the change of each ion concentration of the two water sources. The results show that the quality of goaf water is Na-HCO₃•SO₄, and that of sandstone fissure water is Na-HCO₃•SO₄-Ca•Mg, both of which show weak alkalinity, and their TDS are close to each other. The distribution difference of ion components in goaf water is significantly higher than that in fractured sandstone water. In all ions, except and Na⁺ + K⁺ contents are significantly higher than that in fractured sandstone water, the contents of other ions (SO₄^2-, Ca²⁺, Cl⁻, Mg²⁺, ) are lower than that in fractured sandstone water. HCO₃^- , Na⁺ + K⁺ and SO₄^2- were the most abundant ions in the two water sources. In goaf water, HCO₃^- content is high, SO₄^2- content is low, pH value is weakly alkaline, and TDS is slightly higher than that of sandstone fissure water. All these indicate that the goaf water has a short retention time and a smooth recharge channel. It can be seen that the direction of mine prevention and control of goaf water should be to find out the supply channel and source of goaf water, and fundamentally curb the goaf water damage. The results can be used as an effective basis for rapid identification of inrush water source in the research area of Xiangning mining area.