铅冶炼场地粉尘重(类)金属的迁移转化
Heavy metal(loid)s transformation in dust at a lead smelting site
高文艳 1吴凯凯 1陈婷 2李伟展 3陈虹任 1陈玥如 1吴昊 2朱锋 1李海东 4吴川 5薛生国1
作者信息
- 1. School of Metallurgy and Environment,Central South University,Changsha 410083,China
- 2. Scientific Research Academy of Guangxi Environmental Protection,Nanning 530000,China
- 3. Department of Science and Environmental Studies,The Education University of Hong Kong,Hong Kong 999077,China
- 4. Nanjing Institute of Environmental Sciences,Ministry of Ecology and Environment,Nanjing 210042,China
- 5. School of Metallurgy and Environment,Central South University,Changsha 410083,China;Department of Science and Environmental Studies,The Education University of Hong Kong,Hong Kong 999077,China
- 折叠
摘要
粉尘是铅冶炼场地土壤重(类)金属的来源之一,但粉尘中重(类)金属的迁移转化机制尚不明确.本文系统研究了此过程中重(类)金属的地球化学行为和解离机制.实验结果表明,两类粉尘样品中Pb、Zn、Cd和As的总量和浸出均超过标准,其中,两类粉尘中约有80%的Pb、Zn为生物可利用态,底吹炉粉尘中70%以上的As为弱酸提取态,而还原烟化炉粉尘弱酸提取态的重金属为Cd,占比为60%.Pb同位素结果显示,表土中97.12%的Pb来自冶炼过程中排放的粉尘.XRD和MLA结果表明,粉尘中的主要矿物为PbSO4、ZnSO4和CdSO4,表土中的矿物主要是石英、方解石、白云石和白云母.利用地球化学模型对主要矿物进行拟合发现,在酸性条件下,Pb、Zn和Cd的解离主要依赖于硫酸盐矿物,而As的解离与氢氧化铁的吸附作用有关.
Abstract
Emitted dust is the major contributor of heavy metal(loid)s in soils located near lead(Pb)smelters,but the mechanisms for transfer of the heavy metal(loid)s in dust are uncertain.The study systematically investigated the geochemical behaviors and liberation mechanisms of heavy metal(loid)s in this process.The results show that Pb,Zn,Cd,and As in two types of dust samples exceeded the allowable standards,and about 80%of Pb and Zn were present in mobile and bioavailable fractions.More than 70%of arsenic in bottom-blowing furnace dust existed in an acid-soluble fraction,while 60%of cadmium in reducing and fuming dust existed in the acid-soluble fraction.Pb isotope results showed that 97.12%of the Pb in the topsoil came from dust emitted during the smelting process.XRD and MLA results illustrated that PbSO4,ZnSO4,and CdSO4 were the major minerals in the dust,while the mineral phases of the topsoil were mainly quartz,calcite,dolomite,and muscovite.Based on a combination of mineralogical investigations and geochemical modelling,our findings suggest that liberation of the Pb,Zn,and Cd was primarily dependent on sulfate minerals under acidic conditions,whereas the liberation of As was related to adsorption by iron hydroxide.
关键词
铅冶炼粉尘/重(类)金属/地球化学迁移/化学形态/污染场地Key words
lead smelting dust/heavy metal(loid)s/geochemical transfer/chemical speciation/contaminated site引用本文复制引用
基金项目
国家重点研发计划(2019YFC1803601)
国家自然科学基金(42177392)
Research and Development Office,the Education University of Hong Kong,China(RG 45/2022-2023R)
Dean's Research Fund of Education University of Hong Kong,China(IRS-4 2023)
出版年
2024
NETL
NSTL
万方数据