Application of anaerobic digestion products of municipal solid food wastes in treating wastewaters
ABS TRACT: Anaerobic digestion is the breakdown of biodegradable organic material by microorganisms in the absence of oxygen or in an oxygen starved environment. This technology is superior to the landfilling and also the aerobic composting. The aim of the present study was to examine whether the effluent Volatile Fatty Acids from the anaerobic acidogenesis of the urban food waste can be used, due to its high value in organic elements, as an external carbon source for the denitrificationin waste water treatment plants. The results showed that Volatile Fatty Acids concentration in mgCOD/L in the fermentation was in the range between 3,300 mg COD/L and 6,560 mg COD/L. The n butiric acids had the highest concentration in mg COD/L followed by the propionic and acetic acid, while the valeric acid had the lowest concentration,also the concentration of the acetic and valeric acid were stable over the time. Opposite to these, the propionic and n butyric acid showed high variability in the concentration, especially the nbutyric acid. The specific denitrification rate tests showed that the ethanol cultivated biomass was more successful in using the effluent of the urban food waste digestion as carbon source than methanol cultivated biomass. The specific denitrification rate tests results of the experiment showed that the average of 0.15 an 0.51 mg N/mg for methanol and ethanol cultivated biomass respectively.