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Chemically Enhanced Primary Treatment of Wastewater

Waste Water Treatment

  1. Frédéric J. F. Chagnon,
  2. Donald R. F. Harleman

Published Online: 15 JUL 2005

DOI: 10.1002/047147844X.ww63

Water Encyclopedia

Water Encyclopedia

How to Cite

Chagnon, F. J. F. and Harleman, D. R. F. 2005. Chemically Enhanced Primary Treatment of Wastewater. Water Encyclopedia. 1:659–660.

Author Information

  1. Massachusetts Institute of Technology, Cambridge, Massachusetts

Publication History

  1. Published Online: 15 JUL 2005


Chemically enhanced primary treatment (CEPT) is a wastewater treatment process in which small doses of chemical compounds are added to wastewater in order to increase the operating efficiency of sedimentation basins. The chemicals cause the suspended particles to clump together via the processes of coagulation and flocculation. The particle aggregates, or flocs, settle faster and thus enhance the treatment efficiency, which is measured as the removal of solids, organic matter, and nutrients from the wastewater. The chemicals utilized in CEPT are the same ones commonly added in potable water treatment (e.g., metal salts and/or organic polymers).


  • coagulation;
  • flocculation;
  • sedimentation;
  • basins;
  • secondary;
  • treatment