Comparison of Start-up Characteristics and Odorant Removal Efficiencies of Biological Aerated Filters Different in Filling

Two biological aerated filter (BAF) reactors using different fillings, separately, i.e. ceramic pellets (CPs) and granular active carbon (GAC), were built and used to remove geosmin and 2-MIB from water. Further, their start-up characteristics were investigated by comparing odorant removal efficiencies and start-up time. At the same influent water, the two BAFs were quite similar in dissolved organic carbon (DOC) removal efficiency and both removal rates stabilized over 70% in 24 days. However, the two BAFs differed significantly in start-up time for removing geosmin and 2-MIB, separately, i.e. 30 and 26 days respectively in CPs-BAF and 62 and 43 days respectively in GAC-BAF. Moreover, the geosmin removal rates in GAC-BAF and CPs-BAF were stable at about 95% and 69%, respectively, and the rate and stability for geosmin removal of the former was obviously higher than of the latter. And the removal rates of 2-MIB in GAC-BAF and CPs-BAF were similar to each other and stable at about 75% and 73%, respectively, but the stability of the former was higher than of the latter.