Anaerobic Acidogenesis of Food Waste and Application as a Supplemental Carbon Source for Denitrification

This study investigated the possibility of volatile fatty acids (VFA), produced via fermentation of food waste, to be used as a carbon source for the process of enhancing denitrification during biological nitrogen removal. The VFA were generated in a 61 jacketed fermentation reactor operated at 37°C and a controlled pH of 6.5. The average conversion rate of the feed total Chemical Oxygen Demand (tCOD) to fermentate soluble Chemical Oxygen Demand (sCOD) was on average 34% while the conversion to VFA COD was on average 9%. Batch denitrification tests performed with two types of biomass, one cultivated with methanol and another with ethanol as carbon sources revealed promising specific denitrification rates (sDNR) of 0.15 and 0.5 mg NO3−-N/mg VSS-d for the methanol and ethanol cultivated biomass respectively.