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

Abstract

This study assessed the effectiveness of integrating electrocoagulation, magnetic fields, and ozonation technolo - gies to remove chemical oxygen demand (COD) and total suspended solids (TSS) from tannery wastewater. Fur - thermore, the effects of their key operating factors were determined. To achieve this goal, an electrocoagulation re - actor 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 (O 3 ) are considered the influencing factors. Likewise, the removal percentages of COD and TSS serve as response indicators. The results indicate that T, I, and O 3 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 O 3 = 10 mg/l; and for TSS, the optimal conditions are I = 5.72 A, T = 28 min, and O 3 = 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 the pollution issues caused by the tannery industry.