Dimensioning of Final Settling Tanks of Large Activated Sludge Plants for High Quality Effluent

The activated sludge tank and the final settling tank represent one operating unit in which the mixed liquor suspended solids indicate the main parameter. This parameter depends on the efficiency of the final settling tank so that this building determines the capacity of the whole wastewater treatment plant. The effluent quality improves with the separation capability of the clarifier because the suspended solids contain relatively large concentrations of BOD5 and COD and significant values of organic nitrogen and total phosphorus.