The Actiflo Ballasted Sedimentation System including two (2) separate treatment trains each consisting of a Coagulation Tank, Maturation Tank, and Settling Tank. Ferric Sulfate and Polymer are added to the Actiflo System Influent to aid in coagulation/flocculation of suspended matter. Sand is also added for ballast, but is not required if Influent Flow is less than 15.6 MGD or 7.8 MGD per Actiflo train
During dry weather flow of less than 15.6 MGD, the sand is not fluidized. Settled sludge is pumped from the bottom of each train settling tank to hydrocyclones used to separate the sand and primary sludge. The sand is returned to the Actiflo systems and the sludge is discharged to the Gravity Thickener.
The Biostyr Biological Aerated Filtered (BAF) System is an up flow biological aerated filter used to provide removal of residual suspended solids and soluble CBOD as well as nitrification. Eight (8) BAF separate cells are provided and flow is divided evenly between the cells in operation. Cells are automatically brought on and off line based on the demand flow and ammonia loading to the BAF system. It is predicted that during average flow conditions the filters will require backwashing approximately every 48 hours, while under peak flow conditions, the filters will require backwashing approximately every 24 hours. Waste BAF backwash is stored in the Spend Backwash Tank and returned to the Actiflo Influent Channel using two (2) variable speed dry pit submersible pumps.
BAF System Effluent flows by gravity to the Normal Flow Chlorine Contact Tank. Sodium Hypochlorite is added immediately upstream of the Normal Flow Chlorine Tank and also at the Peak Flow Chlorine Contact Tank inlets for disinfection. Sodium Bisulfite is added downstream of the Chlorine Contact Tanks to remove residual chlorine prior to discharging to the Fox River.
Solids Handling Train