title: Reduction of heavy metals in residues from the dismantling of waste electrical and electronic equipment before incineration.
abstract: Residues disposal from the dismantling of waste electrical and electronic equipment are challenging because of the large waste volumes, degradation-resistance, low density and high heavy metal content. Incineration is advantageous for treating these residues but high heavy metal contents may exist in incinerator input and output streams. We have developed and studied a specialized heavy metal reduction process, which includes sieving and washing for treating residues before incineration. The preferable screen aperture for sieving was found to be 2.36mm (8 meshes) in this study; using this screen aperture resulted in the removal of approximately 47.2% Cu, 65.9% Zn, 26.5% Pb, 55.4% Ni and 58.8% Cd from the residues. Subsequent washing further reduces the heavy metal content in the residues larger than 2.36mm, with preferable conditions being 400rpm rotation speed, 5min washing duration and liquid-to-solid ratio of 25:1. The highest cumulative removal efficiencies of Cu, Zn, Pb, Ni and Cd after sieving and washing reached 81.1%, 61.4%, 75.8%, 97.2% and 72.7%, respectively. The combined sieving and washing process is environmentally friendly, can be used for the removal of heavy metals from the residues and has benefits in terms of heavy metal recycling.
authors.affiliation: Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, China.
authors.forename: Yu-Yang
authors.initials: YY
authors.lastname: Long
authors.affiliation: Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, China.
authors.forename: Yi-Jian
authors.initials: YJ
authors.lastname: Feng
authors.affiliation: Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, China.
authors.forename: Si-Shi
authors.initials: SS
authors.lastname: Cai
authors.affiliation: College of Quality and Safety Engineering, China Jiliang University, Hangzhou 310018, China.
authors.forename: Li-Fang
authors.initials: LF
authors.lastname: Hu
authors.affiliation: Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, China. Electronic address: shends@zju.edu.cn.
authors.forename: Dong-Sheng
authors.initials: DS
authors.lastname: Shen
mesh_terms: D004581:Electronics; D017745:Incineration / Q000379:methods; D019216:Metals, Heavy / Q000032:analysis / Q000737:chemistry*; D052638:Particulate Matter / Q000737:chemistry; D012037:Refuse Disposal / Q000379:methods
chemical_list: D019216:Metals, Heavy; D052638:Particulate Matter
keywords: Heavy metal; Pretreatment; Reduction; Residues; WEEE