PILOT SCALE ANODIC OXIDATION OF PRETREATED VINASSE USING BORON DOPED DIAMOND ELECTRODES

Abstract

Abstract The anodic oxidation of pretreated vinasse was studied using boron doped diamond (BDD) electrodes at laboratory and pilot scale. In the first stage, two different current densities (60 and 100 mA cm-2) were applied to the cell at different flow rates to confirm that the process was controlled by mass transfer. Assays at different initial pH were performed, finding that this variable does not significantly affect the mineralization of organic pollutants. Three current densities (35, 60 and 100 mA cm-2) were tested at the 25 dm3 pilot scale setup. Also, two different electrolytes (Na2SO4 and NaCl) were used to study the effect of electro-generated oxidant species. The results confirm that the recalcitrant organic compounds that produce the dark brown color on vinasse, like the melanoidins can be effectively treated by the electrochemical oxidation process using BDD electrodes at a pilot scale, with an energy consumption below 50 kWh m-3.

Keywords

• BDD
• Electrochemical Oxidation
• Distillery Wastewater
• Ethanol
• Electrochemistry