ABSTRACT The limitations of traditional direct current–electrocoagulation (DC–EC) in wastewater treatment encompass electrode passivation, high energy consumption and substantial sludge generation. Alternating current–EC, often known as AC–EC, is a technique that was developed to overcome these concerns. This study sets out to compare the effectiveness of several aerated and electrochemical processes in removing chemical oxygen demand (COD) and colour from wastewater. The methods included aerated‐only, DC–EC, AC–EC and aerated‐direct/AC–EC (aerated‐DC/AC–EC). In addition to that, the study assessed the electrical energy use (EEU) that was associated with each process. The experimental results demonstrate that the combined aerated‐AC–EC process attained complete colour removal at 100% efficiency and a 95% efficiency in COD removal, all while consuming less electrical energy—4.50 kWh m −3 —compared to individual processes such as aerated, DC–EC, AC–EC and hybrid aerated‐DC–EC. The hybrid aerated‐AC–EC approach was employed to investigate the impact of significant operational parameters on COD removal efficiency (%) and EEU of wastewater. The parameters included were current density: 0.75 A dm −2 , COD: 3000 mg L −1 , pulse duty cycle: 0.6, pH: 7, treatment time: 2.5 h, inter‐electrode distance: 1 cm, air flow rate: 50 L min −1 and electrode combination: Fe/Fe. The combined effects of the aerated and AC–EC processes were further examined and recorded in this study. The aerated‐AC–EC approach demonstrates a high level of efficiency and effectiveness in contaminant removal from wastewater, positioning it as the most appropriate process in comparison to alternative methods.
Asaithambi et al. (Mon,) studied this question.