Journal of Korean Society of Water and Wastewater (상하수도학회지)

The Korean Society of Water and Wastewater (대한상하수도학회)
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Evaluation of Floc Formation Conditions for Increasing Flotation Velocity in DAF Process

DAF 공정에서 부상속도 향상을 위한 플럭형성 조건 평가

  • 권순범 (한국수자원공사 수자원연구원 국제상하수도연구소) ;
  • 민진희 (한국수자원공사 수자원연구원 국제상하수도연구소) ;
  • 박노석 (한국수자원공사 수자원연구원 국제상하수도연구소) ;
  • 안효원 (한국수자원공사 수자원연구원 국제상하수도연구소)
  • Received : 2006.01.09
  • Accepted : 2006.03.24
  • Published : 2006.04.15
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Abstract

Dissolved air flotation is a solid-liquid separation system that uses fine bubbles rising from bottom to remove particles in water. In order to enhance the flotation velocity and removal efficiency of flocs in the flotation process, we tried to obtain pretreatment conditions for the optimum DAF process operation by comparing and evaluating features of actual floc formation and flotation velocity etc, according to coagulant types and conditions for flocculation mixing intensity by using PIA, PDA, and FSA. Accordingly, generating big flocs that have low density at low flocculation mixing intensity may reduce treatment efficiency. In addition, generating small flocs at high flocculation mixing intensity makes floc-bubbles smaller, which reduces flotation velocity, In this study, it was found that high flocculation mixing intensity could not remove the remaining micro-particles after flocculation, which had negative effects on treated water quality, Therefore, in order to enhance treatment efficiency in a flotation process, flocculation mixing intensity around $50sec^{-1}$ is effective.

Keywords

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