Journal of Korean Society of Water and Wastewater (상하수도학회지)

The Korean Society of Water and Wastewater (대한상하수도학회)
권호 표지

Thickening Characteristics of Activated Sludge by Air Flotation Process

공기부상법을 이용한 활성슬러지의 부상분리 특성

  • 박찬혁 (한국과학기술원 수질환경 및 복원연구센터) ;
  • 홍석원 (한국과학기술원 수질환경 및 복원연구센터) ;
  • 맹주원 (한국과학기술원 수질환경 및 복원연구센터) ;
  • 이상협 (한국과학기술원 수질환경 및 복원연구센터) ;
  • 최용수 (한국과학기술원 수질환경 및 복원연구센터) ;
  • 문성용 (엔바로테크(주) 부설연구소)
  • Received : 2006.08.17
  • Accepted : 2006.10.12
  • Published : 2006.10.15
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Abstract

Air flotation is a solid-liquid separation process that utilizes up-flow microbubbles to thicken activated sludge and enhance clarification efficiency. Continuous air flotation experiments were performed to investigate the effect of operation parameters such as initial MLSS (mixed liquor suspended solid) concentration, air pressure, surface loading rate, air to solid (A/S) ratio, and flotation time on thickening efficiency. An initial activated sludge concentration ranged from 3,000 to 12,000mgSS/L and thickened sludge concentration varied from 6,400 to 28,100mgSS/L. The result showed that the thickening efficiency was mainly dependent on surface loading rate, A/S ratio, and flotation time. The pressure did not affect the thickening efficiency when it kept in the range of 1.6 to 1.8 bar. Experimental results showed that the thickening efficiency of activated sludge was increased only when the feed sludge concentration exceeded 5,000mgSS/L and the thickened concentration was over 20,000mgSS/L. At this time, SS concentration in the clarified liquid was ranged from 5 to 10mg/L.

Keywords

References

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