Abstract
Effects of phenol concentration in the reactor, i.e. phenolic stress, on the biodegradation potential of activated sludge was studied during the process of the acclimation of activated sludge to phenolic wastewater. Three types of reactor operations, i.e. continuous flow operation, aerobic sequencing batch operation, and anaerobic/aerobic sequencing batch operation, and two loading procedure, i.e. elevating load and constant load, were taken into consideration.
Phenol degrading activity of activated sludge acclimated by aerobic batch operation with constant load was the highest. It was suggested that batch operation was effective to select phenol degrading bacteria and moderately high phenolic stress was effective for increasing the biodegradation potential of activated sludge.
Phenol degrading activity of acclimated activated sludge decreased under continuous flow operation and low sludge loading operation of sequencing batch operation. It was suggested that moderately high phenolic stress and moderately high sludge load for sequencing batch operation was preferable for keeping the biodegradation potential of acclimated activated sludge.
