Electrocoagulation for Southern Sarawak’s Peat Water Treatment: Efficiency and Electrode Performance

Abstract

The treatment of peat water poses challenges in places like Sarawak, Malaysia, due to its high turbidity, colour and organic contents. The causes of these water quality problems of peat water are the natural degradation of organic substances in peat soils to fulvic and humic materials, which resist treatment by traditional methods. Common treatment technologies are often ineffective for peat water sources and unsustainable, creating a need for new solutions. Hence, this work aims to investigate electrocoagulation as a sustainable and effective process for the treatment of peat water by using aluminium anodes at different current densities (4–20 A/m²). The study focuses on the trade-off between contaminant removal optimisation and electrode degradation reduction in electrocoagulation applications. The efficiency of turbidity, Total Suspended Solids (TSS), colour removal, and Faradaic efficiency, along with anode corrosion behaviour, are studied. The removal efficiencies were high (i.e., 98% for turbidity, 95% for TSS, and 96% for colour), while an excellent Faradaic efficiency of up to 27% was achieved. The corrosion rate increased with current density, rising from 0.00278 mm/y before electrocoagulation to 0.00511 mm/y at 20 A/m². The Tafel plots clearly showed that the electrochemical reactions had been changed after treatment. These results reveal a trade-off between treatment efficiency and electrode life, which is critical for better design of electrocoagulation treatment systems for sustainable water treatment applications. Overall, this study provides insights to promote electrocoagulation as a promising peat water treatment technology with indications for future research, such as electrode modifications, combined treatments and long-term operational stability for greater applicability and scaling-up of electrocoagulation.