This study investigates the performance of advanced electrocoagulation (EC) for wastewater treatment, with a particular focus on mitigating aluminum electrode passivation through periodic polarity reversal. Initially, the feasibility of EC was evaluated against conventional biological treatment, demonstrating superior removal efficiencies, particularly for biochemical oxygen demand (BOD₅), achieving up to 95.4% removal compared to 88.5% for biological treatment. Operational parameters including current intensity, electrolysis time, and inter-electrode spacing were optimized to maximize pollutant removal while minimizing energy consumption. The pH remained within discharge standards (≈6.5-8.5), and the electrical energy required under optimal conditions ranged from 0.55 to 12.73 kWh/m³, while achieving high removal efficiencies for COD, BOD₅, and TSS. Passivation behavior was analyzed through real-time monitoring of anodic potential, revealing a progressive increase associated with the formation of an insulating oxide layer on the electrode surface. To address this limitation, periodic polarity reversal was implemented, maintaining the electrode potential within an optimal operating range and significantly reducing electrode fouling. Electrocoagulation with polarity reversal achieved a COD reduction improvement of 26.6% in monopolar configuration and 48.1% in bipolar configuration compared to biological treatment, with energy consumption as low as 0.55 kWh/m³. These findings demonstrate that periodic polarity reversal is an effective and practical strategy for enhancing electrocoagulation performance, extending electrode lifespan, and improving the sustainability of wastewater treatment processes for potential industrial-scale applications.
Hocine et al. (Wed,) studied this question.