A New Electrocoagulation Electrode Configuration for The Treatment of Secondary Treated Wastewater

Abstract

Electrocoagulation (EC) is an effective method that is applied to treat a wide range of wastewater. A new electrode configuration is being proposed with the application of the Dielectrophoresis (DEP) force which is expected to enhance the quality of Treated Sewage Effluent (TSE) using unsymmetrical cylindrical aluminum electrodes with alternating current (AC) power source. In this study, the impacts of power supply type and electrode configuration were examined on both Total Phosphorous (TP) removal efficiency and Chemical Oxygen Demand (COD) reduction. Experiment on three different modules were conducted which are unsymmetrical cylindrical aluminum electrodes with AC power source (AC-DEP), symmetrical cylindrical aluminum electrodes with AC power source (AC) and symmetrical cylindrical aluminum electrodes with DC power source (DC). The simulated results showed that the strength of the DEP force increases as the current density increases. Moreover, the DEP force decreases with distance and reaches minimum magnitude at the outer electrode. AC-DEP electrode configuration with 4.3 mA/cm2 current density generates sufficient DEP force that significantly enhance the quality of TSE. The experimental results showed that the maximum removal efficiency of TP is 88.3, 68.2 and 46.0 % and COD reduction of 82.4, 66.8 and 43.3 % with electrode mass consumption of 0.02, 0.15 and 2.12 g under running conditions of 4.3 mA/cm2 current density and 30 min electrolysis time for AC-DEP, AC and DC, respectively.