Utilization of pre-aerated sludge in activated sludge process

The project is to be carried out with Pre aerated Sludge in Activated Sludge Process to observe the effect of Pre-aerated Sludge on BOD, COD , Phosphate, Nitrate, Mlvss mainly in treatment of dairy wastewater. The experimental process involves the conventional Activated Sludge Process (ASP) in which microorganisms are kept in suspension by mixing and aerating the wastewater. The study was conducted by following two methods: 1) utilizing non pre-aerated sludge and 2) utilizing pre-aerated sludge. In the first method the dairy wastewater measuring five liters and 400 ml of non-pre-aerated sludge is filled in the aeration tank and was aerated in the aeration tank where air (or oxygen) is supplied for regular intervals of 30, 60, 90, 120 minutes respectively and samples are collected before aeration and at regular intervals. In the second method the dairy wastewater measuring five liters and 400 ml of pre aerated sludge (with 20, 40 and 60 minutes pre-aeration) are filled in aeration tank. This tank was aerated for regular intervals of 30, 60, 90, 120 minutes respectively and samples were collected before aeration and at regular intervals. The sludge was not recycled to the aeration tank. Testing of different parameters like BOD, COD, Phosphate, Nitrate and Mixed liquor volatile suspended solids were carried out on the samples aerated with different aeration time, with and without pre-aerated sludge and consequent results are to be found. By utilization of pre-aerated sludge, the concentrations of various parameters to be considered for study are to be found decreased when compared with the values of concentration without using pre-aerated sludge. It was be observed that removal of various parameters from wastewater is effective up to the optimum period for pre-aeration beyond this period removal of various parameters from wastewater will not be effective.