Mixing for Coagulation: Organic Polymers, Static Mixers, and Modeling

  • Appiah Amirtharajah
  • S. Casey Jones
Conference paper

Abstract

This paper is a summary of research on the role of mixing in the coagulation process. In particular, the optimal rapid mix G value and detention time were determined for coagulation using an organic, cationic polyelectrolyte. The optimal G value was in agreement with previous studies, but the optimal detention time was in seconds instead of several minutes. Studies on the use of static mixers are also summarized. Comparing the static mixer to a jar test for enhanced coagulation studies showed that the type of mixer is important in determining optimal coagulant doses for TOC removal. This conclusion has important implications for water treatment plants practicing enhanced coagulation. A computational fluid dynamics model of static mixers is also introduced that can provide detailed, quantitative information on the fluid flow and chemical dispersion in static mixers.

Keywords

Clay Hydrolysis Filtration Hydroxide Sedimentation 

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Copyright information

© Springer-Verlag Berlin Heidelberg 1996

Authors and Affiliations

  • Appiah Amirtharajah
    • 1
  • S. Casey Jones
    • 1
  1. 1.School of Civil and Environmental EngineeringGeorgia Institute of TechnologyAtlantaUSA

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