Treatment of vinasse by electrochemical oxidation: evaluating the performance of boron-doped diamond (BDD)-based and dimensionally stable anodes (DSAs)

The removal of colour and organic compounds from vinasses derived from the wine distillery industry was studied using boron-doped diamond-based electrodes and dimensionally stable anodes. The maximum reduction of organic compounds and colour was attained with the use of boron-doped diamond-based electrode after 10 h of operation at a current density of 6.6 mA cm(-2). The current efficiency obtained was about 90% with a specific energy consumption (measured in terms of removal of chemical oxygen demand) of 17 kWh kg(-1) COD removed. The dimensionally stable anodes were capable of removing 6-47% of the organic material and reached 60% decolourisation but with a lower current efficiency (between 85 and 10%) and much higher specific energy consumption values. The anaerobic digestion of vinasse after 1 h of treatment using boron-doped diamond-based electrode showed an effective mineralisation of the organic matter contained in the sample leading to an increase in methane production during anaerobic digestion.