Elemental and mineralogical composition of metal-bearing neutralisation sludges, and zinc speciation-A review

JOURNAL OF HAZARDOUS MATERIALS

卷:416

Review

Chen, Dan Ting¹  Au, Wing Yin¹  van Ewijk, Stijn^1,2  Roy, Amitava³  Stegemann, Julia A.¹ 

[1] Univ Coll London UCL, Dept Civil Environm & Geomat Engn CEGE, Chadwick Bldg,Gower St, London WC1E 6BT, England

[2] Yale Univ, Ctr Ind Ecol, New Haven, CT 06511 USA

[3] Louisiana State Univ, Ctr Adv Microstruct & Devices, Baton Rouge, LA 70806 USA

关键词: High-density sludge;    Electroplating;    Galvanic;    Neutralisation;    Pickling;    Plating;    Hot filter cake;    Cold filter cake;    Industrial sludge;    Aluminium anodisation sludge;   

DOI  :  10.1016/j.jhazmat.2021.125676

来源: Elsevier

【 摘 要 】

Zinc (Zn) in sludges from neutralisation of acidic emissions is a potential environmental pollutant and an element of interest for recovery. Findings regarding the elemental and mineralogical composition of such wastes were aggregated from the literature and examined together for a better understanding of management options, with a focus on Zn. Zn concentrations ranged from 0.006%-22% in 46 acid mine drainage sludges, 0.009%-43% in 72 metal-finishing sludges, 0.024%-11.5% in 32 pyrometallurgical sludges, and 1.71-55.7% in 14 Zn production sludges. The main mineralogical characterization technique was X-ray diffraction, which found the dominant minerals to be calcite, gypsum, quartz, and iron oxides, but could not identify considerable proportions of amorphous phases. More than 60 mineral phases were observed. Crystalline Zn compounds identified included oxides, hydroxides, sulfates, sulfides, and metallic Zn; spinel, olivine and carbonate dominated in pyrometallurgical sludges. Zn may also be present in crystalline phases of low concentration, solid solution, and/or amorphous phases, which could be identified and characterised in more detail using other techniques. Overall, it is concluded that Zn occurs in high concentrations and includes phases that have high potential environmental mobility. Zn recovery seems feasible and would also enable disposal of a less harmful residual.

【 授权许可】

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