模拟酸雨对泉州市区大气降尘重金属的淋溶  

LEACHING OF HEAVY METALS FROM QUANZHOU DUSTFALL WITH SIMULATED ACID RAIN

作　　者：胡恭任[1,2] 戚红璐[2] 于瑞莲[2] 池丹鸿[2] 

机构地区：[1]东华理工大学核资源与环境教育部重点实验室,南昌330013 [2]华侨大学环境科学与工程系,厦门361021

出　　处：《环境化学》2010年第5期884-891,共8页Environmental Chemistry

基　　金：国家自然科学基金项目(40673061);东华理工大学核资源与环境教育部重点实验室开放基金项目(070714)资助

摘　　要：以泉州市区受污染的大气降尘为研究对象,开展大气降尘中重金属(Cu,Pb,Cr,Cd,Zn,Mn,Fe,Ni,V,As,Co)在不同酸度(pH=2.5、3.5、4.5、5.6)酸雨淋溶下的溶出行为研究.结果表明:由于降尘样品本身的中和作用,淋出液的pH呈现出先升后降的趋势,并最终接近淋溶液原始pH.在模拟酸雨作用下,污染降尘中不同重金属呈现不同的溶出规律,金属Cu、Pb、Fe、Ni、Mn、Cd的淋出量随pH的升高而降低,各重金属的溶出基本可分为快速溶出阶段、缓慢溶出阶段或稳定阶段,重金属的溶出不仅与总量有关,还与模拟酸雨pH、环境温度、淋溶时间等因素有关.在pH2.5的酸雨下,累积释放量由大到小的顺序为交通区降尘:Fe>Zn>Mn>Co>Cu>Cr>Ni>Pb>As>V>Cd,工业区降尘:Mn>Fe>Zn>Pb>Cr>Cu>Ni>As>V>Co>Cd.In this paper,two kinds of contaminated dustfall was used to study the leaching process of heavy metals with the simulated acid rain.The dustfall samples polluted by heavy metals were obtained from Quanzhou city,Fujian Province.The pH of the simulated acid rain was controlled at 2.5,3.5,4.5 and 5.6.The tested metals included Cu,Pb,Ni,Zn,Mn,Cr,V,Co,Fe,As and Cd.The investigation revealed,pH of the leaching fluid first increased and then declined and ultimately,close to the original leaching solution pH.Under simulated acid rain,different heavy metals of polluted dust show different dissolution patterns.When the pH of the simulated acid rain increases,the release of Cu,Pb,Fe,Ni,Mn,Cd decrease.Dissolution of the heavy metals can be divided into the rapid dissolution stage,the slow dissolution stage or stable stage.The leaching of heavy metals not only dependson the total amount of heavy metals,but also on the simulated acid rain pH,temperature,leaching time,and other factors.At rain pH 2.5,the cumulative leaching of the order follows： J3-1（dustfall of traffic zones）： Fe〉Zn〉Mn〉Co〉Cu〉Cr〉Ni〉Pb〉As〉V〉Cd,J40（dustfall of industrial zones）： Mn〉Fe〉Zn〉Pb〉Cr〉Cu〉Ni〉As〉V〉Co〉Cd.

关 键 词：模拟酸雨 大气降尘 重金属 淋溶 

分 类 号：X513[环境科学与工程—环境工程]