The performance of electrocoagulation process for decolorization and COD removal of highly colored real grey water under variable operating conditions

Abstract

Grey water (GW) reclamation offers a viable solution to address water scarcity. However, the variation in its quality and quantity makes treatment options big challenges. In the last years, Electrocoagulation (EC) has emerged as an effective method for treating GW. This study assessed the performance of a lab-scale EC reactor in treating GW with high concentrations of chemical oxygen demand (COD) and color (1290 mg/L and 2540 Pt-CO, respectively), sourced from various origins. The impact of different operational parameters, including electrode material (Iron 'Fe' and Aluminum 'Al'), electrode spacing (1 and 2 cm), and current density (5, 10, 15, and 20 mA/cm²), was evaluated. Results showed minimal impact from electrode spacing, possibly due to the short electrolysis time (10 min). However, Al based electrodes outperformed Fe based electrodes, offering reduced health risks from metal contamination. Operating with Al electrodes at a current density of 5 mA/cm² led to substantial removal of COD (≥ 82 %) and color (≥ 97 %) while maintaining low operational costs. This study further supports the viability of EC as an effective method for treating grey water, even at high contaminant levels.

Keywords

• Grey water
• Electrocoagulation
• COD removal, wastewater treatment