| Blue Plains Advanced Wastewater Treatment Plant (AWTP) uses methanol as its external carbon source for denitrification; glycerol is being investigated as a replacement. Using two sequencing batch reactors (SBRs) in an incubator at 20°C, heterotrophic microbes from the east secondary and nitrification systems were used as seed. The activated sludge acclimation time was observed; the biomass yield coefficient (Y), C/N ratio and SDNR were determined with low food to mass (F/M) testing. The mixed culture was fed secondary effluent from Blue Plains. During acclamation, NOX, COD, and biomass yield profiles were run to determine when steady-state was achieved. The reactors took 21 days to acclimate to glycerol. The mean yield coefficient for both reactors was 0.67 g VSS/g COD. The mean C/N ratios were both 8.7 g COD/g NO X-N and the SDNR were 3.57 and 3.53 mg/g VSS/hr for reactors A and B, respectively. All of these findings show glycerol is not an efficient or cost-effective alternative to methanol for heterotrophic denitrification under the conditions of this study. |
