Different methods applied to remove pollutants from real epoxy paint wastewater: modeling using the response surface method

Comparing between classical and advanced methods for the treatment of industrial wastewater is extremely important to optimize factory operations and cost, and reduce the effects on environment. In the present study, some classical and advanced processes were assessed for chemical oxygen demand (COD) removal, the biggest problem in the wastewater from a factory producing epoxy paints. The response surface methodology was used for optimization. While the chemical coagulation (CC) and classical Fenton (CF) processes were used as the traditional methods, the electrocoagulation (EC) and electro-Fenton (EF) processes were used as the advanced methods to treat wastewater. As a result, the highest COD removal efficiencies were obtained in EF (97.8%) and CF (88.6%), respectively. Low COD removal efficiencies (43.5% and 47.5% respectively) were achieved in coagulation-based processes (CC and EC). Operating cost for CF calculated as 2.15 euro/m(3). Considering in terms of treatment efficiency, sludge volume and operating cost, CF is the most suitable option for the management of epoxy paint wastewater (EPW). These results also show that Fenton-based methods provide higher removal yields for the treatment of EPW. In other words, it is stable wastewater and the presence of hydroxyl radicals is required for its successful management.