Investigation of direct and alternating current–electrocoagulation process for the treatment of distillery industrial effluent: Studies on operating parameters

Abstract

The main objective of this study is to analyze the influence of direct and alternating – current on electrocoagulation process in terms of % color and % COD removal along with electrical energy consumption from distillery industrial effluent. The percentage of color and COD removal and electrical energy consumption were about 90.57%, 86.54% and 3.50 kWhr/m3 with Direct – Current Electrocoagulation (DCE). For Alternating – Current Electrocoagulation (ACE), it was 100%, 95% and 3.20 kWhr/m3, respectively at the optimal experimental condition of COD – 3000 mg/L, initial wastewater pH – 7, current density – 0.4 A/dm2, inter–electrode spacing – 1 cm, combination of electrode – Fe/Fe, pulse duty cycle – 0.45, frequency – 50 Hz and treatment time – 3.5 h. The ACE was more successful in eliminating % color and % COD with less electrical energy consumption than DCE process. In DCE, the formation of an impermeable oxide layer on the cathode and the occurrence of corrosion on the anode due to oxidation have decreased the efficiency of this process compared to the ACE process. As a result, experimental findings have shown that with less electrical energy usage and process efficiency, the ACE could be a more promising solution to removing pollutants from wastewater and industrial effluent than the DCE method.