Electrocoagulation and ozonation: a hybrid technique to treat colored effluents from the textile industry

This study evaluated the effectiveness of a hybrid treatment system of ozonation and electrocoagulation for removing color from textile wastewater. The hybrid treatment system was carried out in a semi-pilot scale and continuous flow, with real textile wastewater. Different ozonation and electrocoagulation conditions were simultaneously evaluated in six experimental stages, combining ozone application rates of 0.0 and 13.6 mg/L with the electrical currents of 0.0, 15.8, 22.1 and 28.5 A. The hybrid treatment system had a color removal efficiency of 55.4% after the application of 3.45 g/L of iron and 0.27 g/L of ozone. The increase of electrical current did not increase color removal. Significant color removal efficiencies were only observed in the stages that simultaneously applied both electrocoagulation and ozonation, indicating a synergistic effect. Thus, continuous systems that combine ozonation and electrocoagulation are promising alternatives for future improvements in wastewater treatment from textile industries.