Optimization of COD and TDS removal from high-strength hospital wastewater by electrocoagulation using aluminium and iron electrodes: Insights from central composite design

Abstract

Simple and eco-friendly, electrocoagulation process is used. It eliminates intractable hospital wastewater pollutants like TDS and COD. The treatment of high-strength hospital wastewater (HWW) using electrocoagulation (EC) using aluminium (Al), iron (Fe), and hybrid (Al and Fe) electrodes was investigated in this study. The effects of two factors, reaction time (20–90 min) and voltage (15–25 V) on COD and TDS treatment efficiencies were examined. The determination of optimal conditions was conducted through the utilization of the central composite design (CCD). The optimization results for both TDS and COD were as follows: Fe-Fe performed best at 15 V for 57 min (57% and 60%), Al-Al at 16 V for 51 min (65% and 59%), and Al-Fe at 20 V for 51 min (59% and 61%). Based on energy consumption, the optimal electrode pattern was the Al-Al experimental set, with 3.17 kWh/kg COD and 8.31 kWh/kg TDS.