Study on the Application of Electro Coagulation for Wastewater Treatment from an Electroplating Plant

The performance of electro coagulation, with thirty-one aluminum electrodes coated with a layer of graphite, in the treatment of metal ions (Cu²⁺, Zn²⁺ and Cr⁶⁺) containing wastewater, had been investigated. The basic principle of electrolysis and several working parameters, such as pH, operating time and connection mode were deeply analyzed. The results show that monopolar connection is the most cost-effective for both electrode types. When the current density was 6 A/dm², initial pH was 6, operating time was 70min, connection mode was monopolar connection and inter-electrode distance was 1.5 cm, removal efficiency of Cu²⁺,Zn²⁺,Cr⁶⁺ and COD are 99.8%, 99.1%, 96.2% and 61.4%, respectively. In addition, energy consumption of the experiment was 7.58 kWh/m³. The method was found to be highly efficient and to overcome the drawbacks of conventional electroplating wastewater treatment technologies.