Naslov
Electroplating wastewater treatment by the combined electrochemical and ozonation methods

Autori
Oreščanin, Višnja ; Kollar, Robert ; Lovrenčić Mikelić, Ivanka ; Nađ, Karlo

Izvornik
Journal of Environmental Science and Health. Part A : Toxic/Hazardous Substances and Environmental Engineering (1093-4529) 48 (2013), 11; 1450-1455

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
ozonation ; electrochemical treatment ; wastewater ; electroplating ; heavy metals ; TOC ; COD ; iron anode ; aluminum anode

Sažetak
This paper presents a pilot plant study of the electroplating wastewater treatment by the processes of electroreduction with iron electrode plates, and electrocoagulation/ozonation with aluminum electrode set, followed by the process of ozonation. The initial effluent was found to be highly enriched in heavy metals and to possess the elevated levels of organic contaminants. The values of Cr(VI), Fe, Ni, Cu, Zn, Pb, TOC, and COD exceeded the upper permissible limits of 63, 220.2, 1.1, 7, 131.3, 1.7, 12.3, and 11.4 times, respectively. The heavy metal removal was forced either by the coagulation/flocculation using Fe(II), Fe(III), and Al(III) ions released into the treated solution by the electrochemical corrosion of the sacrificial iron and aluminum electrodes, or the precipitation of the metal hydroxides as well as co-precipitation with iron and aluminum hydroxides. The principle organic matter destruction mechanisms were ozone oxidation and the indirect oxidation with chlorine/hypochlorite formed by the anodic oxidation of chloride already present in the wastewater. Following the combined treatment, the removal efficiencies of Cr(VI), Fe, Ni, Cu, Zn, Pb, TOC, and COD were 99.94%, 100.00%, 95.86%, 98.66%, 99.97%, 96.81%, 93.24%, and 93.43%, respectively, thus complying with the regulated values.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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