Reducing Tannery Wastewater Pollutants through a Magnetic-Field and Ozone-Treatment Electrocoagulation System using Response Surface Methodology

Abstract

This study assesses the effectiveness of integrating electrocoagulation, magnetic fields, and ozonation technologies to remove chemical oxygen demand (COD) and total suspended solids (TSS) from tannery wastewater. Furthermore, the effects of their key operating factors are determined. To achieve this, an electrocoagulation reactor coupled with a magnetic-field generator was used and the response surface methodology was applied through a Box-Behnken experimental design. Here, current intensity (I), treatment time (T), and ozone concentration (O3) are considered influencing factors. Likewise, the removal percentages of COD and TSS serve as response indicators. The results indicate that T, I, and O3 are significant for the removal of COD and TSS at a confidence level of p-value < 0.05. For COD, the optimal operating conditions are I = 6.8 A, T = 30 min, and O3 = 10 mg/l; and for TSS, the optimal conditions are I = 5.72 A, T = 28 min, and O3 = 7.8 mg/l. These conditions yield removal efficiencies of 41.8% for COD and 97.9% for TSS. The findings suggest that integrating these technologies is a viable alternative for mitigating pollution issues caused by the tannery industry.