Combined electrocoagulation and electro-oxidation of industrial textile wastewater treatment in a continuous multi-stage reactor

Abstract

A combined electrocoagulation (EC) and electrochemical oxidation (EO) industrial textile wastewater treatment potential is evaluated in this work. A fractional factorial design of experiment showed that EC current density, followed by pH, were the most significant factors. Conductivity and number of electrooxidation cells did not affect chemical oxygen demand degradation (DCOD). Aluminum and iron anodes performed similarly as sacrificial anodes. Current density, pH and conductivity were chosen for a Box-Behnken design of experiment to determine optimal conditions to achieve a high DCOD minimizing operating cost (OC). The optimum to achieve a 70% DCOD with an OC of USD 1.47/m(3) was: pH of 4, a conductivity of 3.7 mS/cm and a current density of 4.1 mA/cm(2). This study also shows the applicability of a combined EC/EO treatment process of a real complex industrial wastewater.