摘要
受去产能政策、能源枯竭等因素影响,近年来我国废弃煤矿数量激增,大量煤矿的关闭伴随着严重的水环境污染问题。江西高泉废弃煤矿区下游浅层地下水硫酸盐质量浓度远远高于《地下水质量标准》(GB/T 14848-2007)Ⅴ类限值,亟需查明其污染来源及路径。为研究其地下水硫酸盐硫源,采集了该矿区主井涌水及地下水环境监测井共6组样品,分析了其基本化学组分、δD、δ^(18)O同位素和δ^(34)S同位素,综合运用水化学类型法、环境同位素法以及水文地球化学模拟法,揭示了其成因。研究结果表明,高硫酸盐地下水分布于主井涌水地表径流区域,在主井上游、矿区侧翼、垭口出口处地下水则不表现高硫酸盐特征;地下水主要补给来源为不同高程的大气降水,并可能存在混合作用;2组高硫酸盐地下水和主井涌水SO_(4)^(2-)质量浓度分别为679、1790、1620 mg/L,但δ^(34)S数值在同一水平线,分别为-29.65‰、-30.93‰、-30.59‰,表明高硫酸盐地下水硫一致来源于黄铁矿;水文地球化学模拟结果表明,含氧大气降水氧化煤层中黄铁矿形成高硫酸盐酸性排水后,被大气降水持续补给稀释,再途经碱性含水层,被白云石和方解石等矿物中和形成高硫酸盐、pH值中性特征地下水,最终通过主井涌出地表并下渗污染下游浅层含水层。
Influenced by factors such as overcapacity reduction policies and energy depletion,the number of abandoned coal mines in China has surged in recent years,with the closure of numerous mines accompanied by severe water environmental pollution issues.In the downstream area of the Gaoquan Abandoned Coal Mine in Jiangxi Province,the sulfate content in shallow groundwater is significantly higher than the Class Ⅴ limit specified in the Groundwater Quality Standards(GB/T 14848-2007),severely impacting the surrounding ecological environment and crop growth.There is an urgent need to ascertain the pollution sources and pathways.To investigate the sulfate sulfur sources in the groundwater,a total of 6 samples were collected from the main mine water inflow and groundwater environmental monitoring wells in the mine area.Basic chemical components,δ^(18)O and δ^(34)S isotopes,and δ^(34)S isotopes were analyzed.Comprehensive utilization of hydrochemical typing,environmental isotope methods,and hydrogeochemical modeling revealed its genesis.The results indicate that:1)High-sulfate groundwater is distributed in the surface runoff area of the main mine water inflow,while groundwater upstream of the main shaft,on the side wings of the mining area,and at the pass outlet does not exhibit high sulfate characteristics.2)The primary recharge source of groundwater is atmospheric precipitation at different elevations,with possible mixing effects;the SO_(4)^(2-)contents of the two groups of high-sulfate groundwater and main shaft water inflow are 679,1790,and 1620 mg/L,respectively,but their δ^(34)S values are on the same horizontal line,at-29.65‰,-30.93‰,and-30.59‰,respectively,indicating that the sulfur in high-sulfate groundwater consistently originates from pyrite.3)The results of hydrogeochemical modeling suggest that oxygenated atmospheric precipitation oxidizes pyrite in coal seams to form high-sulfate acidic drainage,which is then continuously diluted by atmospheric precipitation recharge.As it passes through alkaline aquifers,it is neutralized by minerals such as dolomite and calcite,forming groundwater with high sulfate and neutral pH characteristics.Ultimately,this water emerges at the surface through the main mine and infiltrates to contaminate the shallow aquifer downstream.
作者
周礼亚
陈诗峰
余圣品
万平强
盛明株
叶泰海
程林辉
ZHOU Liya;CHEN Shifeng;YU Shengpin;WAN Pingqiang;SHENG Mingzhu;YE Taihai;CHENG Linhui(Nanchang Key Laboratory of Hydrogeology and High Quality Groundwater Resources Exploitation and Utilization(Jiangxi Institute of Survey&Design LTD.),Nanchang,Jiangxi 330095,China;Hydrogeology Brigade of Jiangxi Geological Bureau,Nanchang,Jiangxi 330095,China)
出处
《中国煤炭》
北大核心
2025年第12期231-243,共13页
China Coal
基金
江西省技术创新引导类计划项目(2023KDG01010)
江西省地质局青年科学技术带头人培养计划项目(2023JXDZKJRC07)
南昌市水文地质与优质地下水资源开发利用重点实验室项目(20231B11)。
关键词
废弃煤矿
高硫酸盐型地下水
矿坑排水
环境同位素
水文地球化学模拟
abandoned coal mine
high-sulfate groundwater
acid mine drainage
environmental isotopes
hydrogeochemical modeling
