INVESTIGATION OF ELECTROCOAGULATION AND ELECTROOXIDATION METHODS OF REAL TEXTILE WASTEWATER TREATMENT

Abstract

Industrial wastewaters are becoming a bigger problem every day depending on the development of the industry and technology.  The textile industry discharges a large amount of wastewater containing non-biodegradable organic compounds and inorganic chemicals to the environment after various steps of production processing. Electrochemical technologies such as electrochemical oxidation, electrochemical reduction, indirect electro-oxidation with strong oxidants and electrocoagulation have received considerable attention for treating dye wastewaters during last decade. In this study, it was investigated the treatability of wastewater from textile industry by electrochemical treatment methods. Effect of important operating parameters such as, electrode type and combination (Al-Al, Fe-Fe, Al-Fe, Fe-Al, Pt-Fe), pH, reaction time and potential were investigated on removal efficiency of color and chemical oxygen demand (COD).  The study was performed by both electrocoagulation and electrooxidation method using real textile wastewater. The initial color, and COD concentrations of the wastewater were 395 Pt-Co and 1040 mg/L, respectively. At the end of the electrocoagulation experiments, concentrations of color and COD were decreased to 28 Pt-Co and 115 mg/L, respectively. Results showed that at pH 3 and 6 V potential, up to 93% color and 89% COD removal efficiencies were obtained in the reactor consisting of Fe-Fe electrodes. COD and color were removed at the rate of 88% and 92%, respectively in the study done with Al-Al couple at 10 V in natural pH (6.96). COD removal was achieved in the ratio of 93% at 6V as a result of the electrooxidation study with a couple of Pt-Fe electrodes. The study showed that the removal process was promising and it was reached to the discharge limit values for the color and COD with each electrode couple specified in the regulation.