Electrochemical treatment of simulated beet sugar factory wastewater

Electrochemical treatment of simulated beet sugar factory wastewater was studied as an alternative treatment method for the first time in literature. Through the preliminary batch runs, appropriate electrode material was determined as iron due to high removal efficiency of chemical oxygen demand, COD, and turbidity. The effect of operational conditions, applied voltage, electrolyte concentration and waste concentration on COD removal percent and initial COD removal rate were investigated through response surface methodology, RSM. In the set of runs, highest COD removal and COD initial removal rate were realized as 86.36% and 43.65 mg/L min, respectively, after 8 h at the applied voltage of 12 V, 100% waste concentration with 50 g/L NaCl. Treatment conditions were optimized by RSM where applied voltage was kept in the range, electrolyte concentration was minimized, waste concentration, COD removal percent and COD initial removal rate were maximized at 25 °C. Optimum conditions at 25 °C were estimated as 12 V applied voltage, 100% waste concentration and 33.05 g/L electrolyte concentration to achieve 79.66% and 33.69 mg/L min for COD removal and COD initial removal rate, respectively. Kinetic investigations denoted that reaction order of electrochemical treatment reaction was 1.2 with the activation energy of 5.17 kJ/mol. These results support the applicability of electrochemical treatment to the beet sugar factory wastewater as an alternative advanced wastewater treatment method with further research.