Standard Article


Municipal Water Supply

  1. Rasheed Ahmad

Published Online: 15 JUL 2005

DOI: 10.1002/047147844X.mw106

Water Encyclopedia

Water Encyclopedia

How to Cite

Ahmad, R. 2005. Flocculation. Water Encyclopedia. 1:252–254.

Author Information

  1. Khafra Engineering Consultants, Atlanta, Georgia

Publication History

  1. Published Online: 15 JUL 2005


The flocculation process aggregates destabilized particles into larger and more easily settleable flocs. The coagulation process destabilizes particles through chemical reactions between the coagulant and the suspended colloids, but flocculation is the transport step that causes the necessary collision between destabilized particles. The purpose of the flocculation process is to promote the interaction of particles and to form aggregates that can be efficiently removed in the subsequent separation processes such as sedimentation, flotation, and coarse bed filtration. In practice, flocculation is accomplished by providing a gentle mixing phase that follows the rapid dispersion of coagulants.


  • coagulation;
  • flocculation;
  • hydraulic flocculation;
  • baffled flocculation;
  • mechanical flocculator;
  • horizontal shaft paddle;
  • vertical shaft paddle;
  • impeller;
  • turbine;
  • velocity gradient;
  • camp number;
  • perikinetic flocculation;
  • orthokinetic flocculation;
  • differential settling