[关键词]
[摘要]
干旱区高矿化度矿井水水化学特征与形成机制研究对西部矿区矿井水零排放及资源化利用具有重要意义。本文采集大海则煤矿地下水及矿井水水样38组,借助piper三线图、同位素技术、Schoeller图、Gibbs图、离子比例系数图等手段研究高矿化度矿井水的水文地球化学特征,并揭示其成因机制,提出相应的处理措施。研究结果表明,研究区各充水含水层水样以阳离子Na+为主,阴离子以SO42-为主；直罗组地下水及矿井水TDS均超出标准限值,TDS浓度均值分别为2768.57、3057.07 mg.L-1。第四系水、洛河组及安定组地下水水水化学类型以HCO3-Ca型为主,少量HCO3-Na型,直罗组地下水及矿井水水化学类型为SO4-Na型,直罗组地下水与矿井水δD和δ18O值差异小,矿井水主要来源于直罗组地下水补给。矿井水矿化度较高与直罗组地下水矿化度高直接相关。高矿化度地下水在蒸发浓缩和岩石风化控制双重控制下逐步演化形成,钠主要来自钠长石等硅酸盐矿物的溶解、硫酸根来自于石膏的溶解、钙离子除来源于石膏溶解外,还与钙长石等硅酸盐矿物的溶解有关。除此,主要离子的演化的还受阳离子交换作用的影响。矿井水TDS浓度为500～3000mg/L,选择纳滤和反渗透联合对其进行处理,处理后可直接用于生产、生活或者生态。
[Key word]
[Abstract]
The research and analysis of hydrochemical characteristics and formation mechanism of highly mineralized mine water in arid areas are of great significance for zero discharge and resource utilization of mine water in western mining areas. In this paper, 38 sets of groundwater samples collected from Dahaize Coalfield , the hydrochemical characteristics of high salinity mine water by means of Piper tri-line diagram, isotope, Schoeller diagram, Gibbs diagram and ion combination proportion diagram and revealed its formation mechanism. The results indicate that the water samples of each water-filled aquifer in the study area are Na+ and anions SO42-; The average concentrations of TDS in Zhiluo and mine water were 2768.57 mg.L-1 and 3057.07 mg.L-1. The hydrochemical types of groundwater in the Quaternary water, Luohe Formation and Anding Formation are mainly HCO3-Ca , with a small amount of HCO3-Na. The hydrochemical type of water in Zhiluo Formation and mine water are SO4-Na, the groundwater in the ZhiLuo Formation aquifer, the difference of δD and δ18O between Zhiluo formation groundwater and mine water is small, and mine water mainly comes from groundwater recharge of Zhiluo Formation aquifer. The higher salinity of mine water is directly related to the higher salinity of groundwater in Zhiluo Formation. The highly mineralized groundwater gradually evolved under the dual control of evaporation concentration and rock weathering. Sodium mainly came from the dissolution of silicate minerals such as albite, Sulfate came from the dissolution of gypsum, and calcium ions were related to the dissolution of silicate minerals such as calcium feldspar in addition to the dissolution of gypsum. In addition, the evolution of major ions is also influenced by cation exchange.
[中图分类号]
[基金项目]
陕西省自然科学基础研究计划项目(2023-JC-QN-0291),中煤科工集团西安研究院有限公司科技创新基金资助项目(2022XAYJS06)Funds: Natural Science Basic Research Program of Shaanxi Province (2023-JC-QN-0291), Key Project of Science and Technology Innovation Venture Capital of China Coal Science and Industry Group Co., LTD. (2022-2-TD-ZD005)
