what is the function of aeration tank in treatment of sewage?
Treatment of sewage is carried out in two stages: Primary treatment and Secondary treatment.
aeration tanks are used in secondary treatment, there main function is to allow the vigorous growth of useful aerobic microbes into flocs (masses of bacteria associated with fungal filaments in mesh like structures) by constantly agitating primary effluent and pumping air into it. These microbes further consume the major part of the organic matter in the effluent thus treating the effluent.
1. Its easy to agitate or stir in the aeration tank.
2. Air can easily be pumped and thus the growth of microbes which is present in the air.
3. Moreover it also provide a suitable condition for the growth of aerobic bacteria and so , on the organic matter by them.
4. And thus it helpful in decreasing the BOD and the pollution.