废弃铅锌冶炼场地土壤和地下水重金属迁移及预测
Impact of migration and prediction on heavy metals from soil to groundwater in an abandoned lead/zinc smelting site
张云霞 1郭朝晖 1谢慧民 1肖细元 1徐锐1
作者信息
- 1. School of Metallurgy and Environment,Central South University,Changsha 410083,China
- 折叠
摘要
长期的金属冶炼活动会导致重金属在场地土壤和地下水中的富集和扩散.基于机器学习模型研究了某废弃铅锌冶炼场地土壤中重金属向地下水的迁移规律并进行了含量预测.结果表明,场地土壤重金属主要累积在杂填土和素填土层,并存在垂向迁移到地下水的现象.场地土壤中As、Cd和Pb含量平均值均明显超过场地土壤风险筛选值.地下水中Zn、Cd、Pb和As的平均浓度均超过了相应的地下水Ⅵ类限值.土壤重金属污染主要集中在火法冶炼区、湿法冶炼区和原料堆存区.土壤中Cd以活性态为主,Pb以还原态为主.当冶炼场地地下水位低于5 m且土壤Cd含量超过344 mg/kg时,或土壤中活性Pb含量超过5425 mg/kg时,需要对场地土壤和地下水进行协同修复.
Abstract
Long-term metal smelting activities can lead to enrichment and dispersion of heavy metals in the site soil and groundwater.The migration and prediction of heavy metals from soil to groundwater in an abandoned lead/zinc smelting site were studied using machine learning model.The results showed that heavy metals in site soil mainly accumulated in the fill layer,and vertically migrated to groundwater significantly.The mean of Pb,As,and Cd in site soils significantly exceeded the screening value of risk control standard for soil contamination of development land.The mean of Zn,Cd,Pb and As in groundwater exceeded the corresponding groundwater Class VI limit of standard for groundwater quality of China.Soil contamination of heavy metals was serious in the pyrometallurgical area,hydrometallurgical area and raw material storage area,and Cd and Pb in the upper soil layer had a strong migration potential downward with active and reducible state.The synergistic remediation for site soil and groundwater in smelting site was suggested when groundwater level was below 5 m and soil Cd concentration exceeded 344 mg/kg,or when the soil active Pb concentration exceeded 5425 mg/kg.
关键词
铅锌冶炼场地/迁移转化/机器学习/重金属/预测Key words
lead/zinc smelting site/migration and transformation/machine learning/heavy metals/prediction引用本文复制引用
基金项目
国家重点研发计划(2019YFC1803600)
国家重点研发计划(2018YFC1800400)
中央高校基本科研业务费专项(2023ZZTS0727)
出版年
2024
NETL
NSTL
万方数据