A novel cylindrical electrode configuration for inducing dielectrophoretic forces during electrocoagulation

Abstract

The removal of total phosphorous (TP) and chemical oxygen demand (COD) from a secondary treated wastewater (STW) using a new electrocoagulation electrode configuration was evaluated. Three different electrode modules were tested. Module 1 and module 2 used symmetrical aluminum electrodes with a direct current and an alternative current power supply, respectively. In module 3 unsymmetrical electrodes with an alternative current power supply were used. The impact of power supply type, electrode configuration, current density and electrolysis time were evaluated. The experimental results showed that the maximum removal efficiencies of TP and COD were achieved at a current density of 4.3 mA/cm2 and an electrolysis time of 30 min. The removal efficiency of TP was 88.3 %, 68.2 % and 46.0 % with module 3, module 2 and module 1, respectively. The removal efficiency of COD was 82.4 %, 66.8 % and 43.3 % with module 3, module 2 and module 1, respectively. The simulation results showed that in the case of module 3 the strength of the dielectrophoresis (DEP) force increases as the current density increases. Moreover, the DEP force decreases with distance and reaches minimum magnitude at the surface of the outer electrode. 2020 Elsevier Ltd