基于氢氧稳定同位素组成解析庐江矾矿酸性废水来源  

Sources Analysis of Acid Drainage From Lujiang Alunite Mine Based on Stable Isotope Composition of Hydrogen and Oxygen

作　　者：朱红艳 任佳 杨强 周蓓蓓[1] 贾彦武[2] 吕佼佼 周晓平[2] 聂卫波[1] ZHU Hong-yan;REN Jia;YANG Qiang;ZHOU Bei-bei;JIA Yan-wu;LV Jiao-jiao;ZHOU xiao-ping;NIE Wei-bo(Xi'an University of Technology,State Key Laboratory Base of Eco-Hydraulic Engineering in Arid Area,Xi’an 710048,China;Northwest engineering corporation limited,Academy of Urban and Rural Development and EnvironmentalProtection Engineering,Xi’an 710065,China)

机构地区：[1]西安理工大学西北旱区生态水利工程国家重点实验室,陕西西安710048 [2]中国电建西北勘测设计研究院有限公司城乡发展与环保工程院,陕西西安710065

出　　处：《长江流域资源与环境》2021年第12期2938-2948,共11页Resources and Environment in the Yangtze Basin

基　　金：土壤治理工程工作体系及典型技术研究基金资助项目(104-441220019);陕西省科技计划资助项目(2017JM5107);中国博士后科学基金资助项目(2015M582763XB);陕西省教育厅自然科学专项基金资助项目(16JK1539)。

摘　　要：庐江矾矿区受采矿影响,酸性废水严重污染地表水体、矿区土壤,但由于矿区开发历史悠久,采空、塌陷严重,其酸性废水来源不明确,严重影响矿区污染治理进程。采集矾矿区裂隙水、井水、沟道水、沉陷区积水、雨水、矿硐水等不同水体水样,开展其氢氧稳定同位素特征分析,采用直接对比法和MixSIAR模型,明确了矿硐水的来源及不同水体的贡献比例,在此基础上,结合不同水体水质、矾矿石和矿渣成分的检测结果,探究矿硐酸性废水的形成机理。结果表明:(1)矾矿沉陷区积水主要来源于大气降水,但受蒸发影响较大,相对富集重氢、氧同位素,与地下水氢氧稳定同位素组成相差较大;(2)降水会补给浅层地下水,但有一定的滞后效应;(3)降水和裂隙水可能补给沟道水,沟道水也可能补给浅层地下水;(4)井水、裂隙水、沟道水、雨水可能是矿硐水的主要补给水源;(5)不同水体对矿硐水的贡献比例,第一次采样的结果从大到小依次为:雨水39.1%、地下水36.4%、沟道水24.5%,第二次采样的结果从大到小依次为:地下水56.6%、沟道水30.9%、雨水12.5%,两次采样雨水对矿硐水的贡献比例差别较大可能由于降水量不同;(6)明矾水解是矿硐酸性废水的主要成因机理,黄铁矿氧化也会是产生酸性矿山废水的原因之一,平硐以上的采空区提供了形成酸性水的良好条件——充足的氧气和水。研究结果为酸性矿山废水污染的控制、降低矿区土壤相关风险和矿区生态恢复提供科学依据。Under the influence of mining,surface water and soil were seriously polluted by the acid mine drainage of Lujiang alunite mine.However,due to the long history of mining development,the mining and collapse of the mining area are serious,and sources of the acidic drainage is not clear,which seriously affects the process of pollution control in mining area.Water samples from different water bodies of alunite mine were collected,such as fissure water,well water,channel water,subsidence area water,rain water,adit water and so on,analysis of characteristics of hydrogen and oxygen stable isotopes was carried out,the direct comparison method and MixSIAR model were adopted to explicit sources of the adit water and the contribution ratio of different water to it,on this basis,combined with testing results of different water quality,alum ore and slag composition,the formation mechanism of acidic drainage in adit was explored.The results show that water in subsidence areas mainly comes from rainfall,but it is greatly affected by evaporation,and it is relatively rich in heavy isotopes,which is quite different from the stable isotopic composition of hydrogen and oxygen of groundwater.The precipitation can recharge the shallow groundwater,but it has a certain hysteresis effect.The precipitation and fissure water may feed the channel water and the channel water may also feed the shallow groundwater.Well water,fissure water,channel water and rainwater may be the main replenishment sources of mine adit water.For the contribution ratio of different water bodies to the adit water,the results of the first sampling in descending order are rainwater 39.1%,groundwater 36.4%and channel water 24.5%.The results of the second sampling in descending order are underground water 56.6%,channel water 30.9%,and rainwater 12.5%.The contribution ratios of rainwater in the two sampling to the mine adit water are quite different,which may be due to the different precipitation.Alum hydrolysis is the main formation mechanism of acidic mine waste water,

关 键 词：庐江矾矿 氢氧稳定同位素 MixSIAR模型 酸性废水来源 形成机理 

分 类 号：P641.6[天文地球—地质矿产勘探]