基于PHREEQC的地下水化学演化反向模拟

Reverse simulation of groundwater chemical evolution based on PHREEQC

在地下水化学演化研究中,水-岩之间的相互作用对地下水环境评估具有重要意义。为分析某尾矿坝地区地下水化学演化特征,运用PHREEQC软件对该矿区地下水进行水-岩作用地球化学模拟,定量分析该地区地下水反演过程。研究结果表明:(1)该矿区地下水在流动路径中存在的反应主要有溶滤作用、离子交换作用;(2)石膏、方解石、岩盐、CO_(2)溶解量较大,这导致了下游水样中Ca^(2+)、SO_(4)^(2+)、Cl^(-)等含量增大。研究结果对矿区地下水中化学离子的演化趋势具有一定的预测意义,为地下水质量监测及水质保护提供依据。

In the study of groundwater chemical evolution,the interaction between water and rock is of great significance to groundwater environmental assessment.In order to analyze the chemical evolution characteristics of groundwater in a tailings dam area,the water rock geochemical simulation of groundwater in the mining area is carried out by using PHREEQC software,and the evolution process of groundwater in the area is quantitatively analyzed.The results show that:(1)The reactions of groundwater in the flow path in the mining area mainly include leaching and ion exchange;(2)The dissolved amount of gypsum,calcite,rock salt and CO_(2)is large,which leads to the increase of the content of Ca^(2+)、SO_(4)^(2-)、Cl^(-)in the downstream water sample.The research results have certain predictive significance for the evolution trend of chemical ions in groundwater in mining area,and provide basis for groundwater quality monitoring and water quality protection.