Electrochemical treatment of biodigester effluent of maize based starch industry

Abstract

An electrochemical (EC) method for treating industrial wastewater involves compact facilities, easy operation and high efficiency. EC using iron electrode has been employed to effect the reduction of chemical oxygen demand (COD) and colour in biodigester effluent (BDE) of maize based starch industry. The operating parameters considered in this study are voltage (0-30 V), current density (CD) (49.5-247.5 A m^-2) and pH (3.5-9.5). The maximum COD reduction of 89.2% is found at pH 6.5. Colour reduction at the same pH is 97% at current density 99A m^-2. These reductions are achieved at a cost of 26 mg/dm^-3 of BDE of electrode loss with the energy consumption of 7.85 Wh/dm^-3 of BDE. The 55% settling is obtained in 30 min. at pH 6.5. Filtration studies of treated effluent and sludge have also been reported in this study. The EDAX analysis demonstrates the presence of various micro nutrients. TGA analysis of the sludge has also been presented.