Some modification of the conventional activated sludge treatment systems has been developed that serves to improve the efficiency of the activated sludge treatment process. You can also look for more information about aerated wastewater treatment plants via ecoseptic.
Modified aerated wastewater treatment systems are briefly discussed below:
1) Tapered Aeration
As the influent sewage after primary settling enters the top end of the aeration tank; it has relatively high oxygen demand.
At this distance from the inlet of the aeration tank, the oxygen demand increases. This realization has led to modify the processing of waste activated sludge through aeration tapered.
In this case, while the effect was taken at one position of the inlet end, the amount of air supplied to the final position in the larger of which is provided at the outer end.
2) Step Aeration
It is another modification, which is based on the same concept, namely, oxygen consumption of liquor mixture, decreases as the distance from the inlet wastewater aeration tank increases.
In this type of aerated wastewater treatment system, activated sludge was returned was brought in at the end of the aeration tank inlet but the primary waste is taken at a different position from the inlet end for some distance towards the end outlet.
3) Extended Aeration
This type of wastewater treatment system is characterized by a low BOD load and is commonly used to treat wastewater from small communities, schools, and residential colonies.
Aeration period is of 24 hours or more. Extended aeration can receive periodic load without getting angry.