文献类型：期刊文献

英文题名：A closed-loop process for spent washing solution from multi-metal contaminated soil: EDTA reclamation and recycling

作者：Ding, Lei[1,2]; Yuan, Mingzhu[1]; Li, Shuang[1]; Zhou, Jianmin[1]; Wu, Siyu[1]; Zhao, Jianfeng[1]; Cui, Changzheng[1,2]

机构：[1] National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China; [2] Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China

年份：2024

卷号：352

外文期刊名：Chemosphere

收录：EI(收录号：20240915639491)

语种：英文

外文关键词：Chelation - Coagulation - Flocculation - Land reclamation - Soil pollution - Soils - Washing - Wastewater reclamation - Water recycling

摘要：The proper disposal of spent soil washing solution is a great challenge to ethylenediamine tetraacetate (EDTA)-base soil washing technologies, particularly when the solution contains multi-metals. In this paper, we proposed an environmentally friendly disposal of multi-metal spent washing solution, in which the multi-metals were concentrated as hazardous precipitates for further safe disposal, and EDTA was reclaimed and recycled to further wash contaminated soil together with the cleansed process water. The results showed that Cr3+ was poorly removed by sole heavy-metal-capturing agent (HMCA) chelation because of the high solubility of HMCA-Cr, which also yielded a low percentage of EDTA reclamation in the multi-metal spent washing solution. We established a closed-loop process for the disposal of multi-metal spent washing solution by combining coagulation-flocculation-sedimentation and HMCA chelation. The novel recycling process was able to remove 99.67% Cu, 99.62% Pb, 92.48% Cd, 88.19% Sb, 84.38% As, and 82.39% Cr as precipitates from the real spent washing solution, and up to 95.64% of EDTA was reclaimed in the cleansed process water. On the average, the overall efficiency of the reclaimed EDTA solution could reach 65% of the fresh EDTA solution in extracting various HMs from contaminated soil. The recycling method provides an efficient and promising alternative for spent soil washing solution with both EDTA and process water reusage in a closed-loop process. ? 2024 Elsevier Ltd