An oxidation pond is designed for population of 20000 and sewage 2000mg/l and effluent bod 20mg/l .temparature is 24c and k20 0.3/d . The minimum detention period of the pond to achieve desired...

An oxidation pond is designed for population of 20000 and sewage 2000mg/l and effluent bod 20mg/l .temparature is 24c and k20 0.3/d . The minimum detention period of the pond to achieve desired minimum efficiency is?