Addition of hydrogen peroxide in electrocoagulation of dairy liquids

Abstract

Standing out on the national and world scene as an important economic and social activity, the dairy products industries are characterized by their high polluting potential, especially due to the liquid effluents generated. In this context, the present work aims to study the application of the electrocoagulation process applied associatively with hydrogen peroxide (H2O2) in the treatment of dairy effluents using iron electrodes. Effluent treatments were carried out with the electrocoagulation process in a continuous flow reactor. For the method using electrocoagulation, the removal efficiencies in relation to color, turbidity, total organic carbon, chemical oxygen demand and nitrogen removal were 97.2%, 97.0%, 77.5%, 63.3% and 92.2%, respectively. The addition of H2O2 to the beginning of electrocoagulation process in the treatment of dairy effluents did not contribute to an increase in the efficiency of removing organic matter. When applied after an electrocoagulation step, it demonstrated to be efficient, reaching COD removals of 97.7%. Therefore, the electrocoagulation demonstrated to be a technically viable alternative for the treatment of dairy effluent.