Upgrading of an Extended Aeration System to Improve Wastewater Treatment

  • Mohamed Ayoub Associate Professor, Faculty of Engineering, Tanta University, Tanta, 31511, Egypt
  • Ahmed El-Morsy Associate Professor, Faculty of Engineering, Tanta University, Tanta, 31511, Egypt
Keywords: Activated sludge, extended aeration, primary sedimentation, upgrade, wastewater treatment


According to this study, an extended aeration system can be upgraded by adding surface turbine aerators to the tanks and building new primary sedimentation tanks. Moreover, the biochemical oxygen demand (BOD5), chemical oxygen demand (COD), and total suspended solids (TSS) were also observed to be 440, 682, and 212 mg/L after primary settling, respectively. These values represent the removal of about 35% of the organic load and about 68% of the suspended solids, which reduces the organic load and sediments entering the secondary treatment. Furthermore, effluent BOD5, COD, and TSS values were 30, 47, and 32 mg/L respectively, while those permitted values are 60 mg/L of BOD5, 80 mg/L of COD, and 50 mg/L of TSS reflecting the success of the upgrading work.


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