Abstract
Optimum backwashing conditions for activated carbon filtration ponds were examined with a series of model experiments. A backwashing process consists air scouring upward and water backwashing. Since the total head loss of the ponds was caused mainly by a layer between its surface and 50-cm-depth in activated carbon layer, this layer should be washed by air scouring. In the air scouring, the optimum water level, time, and air flow rate were determined by a series of the model experiments. On the other hand, the optimum water amount in the backwashing became a constant product of flow rate and its time theoretically and experimentally. On the optimum conditions, the operation time can be reduced by 70% and backwater can be also reduced by 70% compared with the traditional conditions.
