The food industry generates substantial quantities of wastewater containing organic matter, oils, and pollutants, presenting significant treatment challenges. The present work focuses on the combined ultrasonication and electrocoagulation for treating restaurant wastewater, specifically addressing chemical oxygen demand (COD) removal efficiency and power consumption optimization as stand-alone electrocoagulation is often affected by the passivation problem. The impact of the primary parameters, including voltage (5–25 V), effluent pH (3–9), inter-electrode distance (0.5–2.5 cm) and time (5–45 min), on COD removal, and power consumption in restaurant effluent was assessed through batch experiments utilizing a Central Composite Design (CCD) of response surface methodology (RSM). Additionally, mathematical models were created to predict experimental outcomes. A numerical optimization technique was employed to determine the optimal operating conditions for treating restaurant wastewater with maximum COD removal and minimum power consumption. These conditions (voltage (A): 11.59 V, pH (B): 7.40, inter-electrode distance (C): 1 cm, time (D): 26.8 min) were validated through further experiments, confirming COD removal of 79.2% and energy consumption of 47.89 kWh/m3 in the sono-electrocoagulation process for treatment of restaurant wastewater.
Niju et al. (Wed,) studied this question.