The Use of Al, Cu, and Fe in an Integrated Electrocoagulation-Ozonation Process

Abstract

This study presents the effect of supplying electrochemically generated metallic ions (Al, Cu, and Fe) during an ozonation process for treating industrial wastewater. The pollutant removal efficiencies of the electrocoagulation (EC), ozonation, and coupled EC-ozonation processes were examined by the decrease in chemical oxygen demand (COD) as a function of treatment time. The EC was performed in a raw industrial wastewater, which has contributions from 39 chemical, 34 metal finishing, 22 textile, 11 leather, and 5 automotive plants, at pH (7.3) using a current density of 150 A/m2 for 60 min, giving a 45% reduction in COD. The ozonation process was more effective with the same wastewater, reducing the COD by 52% after 60 min of treatment. Combining the EC and ozonation methods resulted in a synergistic process that improves the reduction of COD in a shorter time. In just 12 min the integrated process reduced the COD by 88%. Thus, the combination of EC and ozonation processes improves noticeably the wastewater quality, decreasing the treatment time and also reducing the sludge production.