Enhancement of heavy metals desorption from the soil by eddy deep leaching in hydrocyclone  

作　　者：Ning Wang Hao Lu Bo Liu Tai Xiong Jianping Li Hualin Wang Qiang Yang 

机构地区：[1]School of Mechanical and Power Engineering,East China University of Science and Technology,Shanghai 200237,China [2]National Engineering Laboratory for High Concentration Refractory Organic Wastewater Treatment Technology,East China University of Science and Technology,Shanghai 200237,China

出　　处：《Journal of Environmental Sciences》2024年第1期242-251,共10页环境科学学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (No.52025103)。

摘　　要：An eddy deep leaching technology was developed in this paper to address the challenge of treating heavy metal contaminants in industrial mining areas.The desorption effect of As,Cd,Sb and Pb was investigated utilizing chemical leaching and physical eddy techniques.It was found that the heavy metals concentration increased with decreasing particle size.The highest proportion of Cd in the form distribution of soil was in the bound to iron and manganese oxides,while the maximum proportion of As,Sb and Pb were in the residual.The optimal solid-liquid ratio of the hydrocyclone was 1:20,and the corresponding separation efficiency and flow rate were 84.7%and 1.76 m^(3)/hr,respectively.The grade efficiency of soil particle separation increases with particle size and exceeds 99%for particles above 1,000μm.Leaching experiments have revealed that oxalic acid(OA)and a combination of oxalic acid and EDTA(OAPE)were more efficient than citric acid(CA)and a combination of citric acid and EDTA(CAPE)for the desorption of heavy metals,respectively.The comparison of OAPE and eddy leaching found that the latter improved the desorption efficiency by 9.4%,7.5%,7.2%and 7.8%for As,Cd,Sb and Pb compared to the former,respectively.The results demonstrated that the eddy leaching technique could further enhance the desorption efficiency of heavy metals.It is expected to provide technical support for soil remediation with reduced usage of leaching agents.

关 键 词：Heavy metals Soil remediation Oxalic acid Eddy leaching HYDROCYCLONE 

分 类 号：X53[环境科学与工程—环境工程]