Separation of pollutants from restaurant wastewater by electrocoagulation

Of late, electrocoagulation has been widely used to treat a wide variety of wastewaters, including textile, dye, electroplating, chemical mechanical polishing wastewaters, etc. Excessive coagulant material may be avoided by electrocclagulation. The contaminants present in wastewaters are maintained in solution by electrical charges. When metal ions of opposite electric charge, provided by an electrocoagulation system, may become unstable and precipitate in a form that is usually very stable. The present work involves the treatment of nearby restaurant effluent in Surat, Gujarat, India. Two different electrodes, aluminum and iron, are used for electrocclagulation. The effect of applied voltage and time of electrolysis on various parameters-such as conductivity, COD, TDS, and turbidity are studied. The removal efficiency of COD is found to be between 50-72% and the optimum time is between 15-30 minutes. Electrocoagulation proved to be a process which could neutralize pH significantly. The major impact of change in electrode is considered and aluminum is found to be better than iron in many respects. The operating cost is estimated from the power cost and cost of electrode material.