Development of Circulating Electrocoagulation as a Novel Technique for the Treatment of Raw Vinasse Effluents of Ethanol Production Industries

Vinasse is a well-known associate of sugar cane/beet ethanol production wastewater. In the present work, the electrocoagulation technique at a constant current intensity combined with circulation flow introduces as a new and economic method for the treatment of vinasse effluent using iron and/or aluminum without changing the initial conditions of sample solution. Spectrophotometric determination was used to quantify the COD and turbidity in effluents as the most regarded vinasse footprints. The proposed CCD method was used as an experimental design, having as independent variables, applied current, pH, electrode material, and the reaction time, evaluated for highest COD, turbidity, and color removal. The optimum conditions for removal of COD, color and turbidity determined by response surface modeling (RSM) showed that the proposed circulating electrocoagulation (CEC) method using aluminum-graphite electrodes at 1 A current, pH 7 and reaction time of 45 min is able to be used with high efficiency for the treatment of vinasse wastewater in ethanol production industry. The proposed method is very simple, cheap and fast and can be used as a pilot system in alcohol factories to recover the water which can, in turn, be utilized for agricultural purposes and other industries.