Journal of Korean Society of Water and Wastewater (상하수도학회지)

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

Improvement of the Thickening Characteristics of Activated Sludge by Electroflotation (EF)

전해부상을 이용한 활성슬러지의 농축효율 향상

  • 최영균 (대구대학교 환경공학과) ;
  • 정태학 (서울대학교 지구환경시스템공학부) ;
  • 염익태 (성균관대학교 토목환경공학과)
  • Received : 2005.01.06
  • Accepted : 2005.05.23
  • Published : 2005.06.15
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Abstract

The performances of electroflotation (EF) on the thickening of activated sludge were investigated using laboratory scale batch flotation reactors. Four activated sludges including bulking sludges were tested. After 30minutes of EF operation, 57-84 % of sludge volume reduction could be achieved by EF, while only about 1.5-14% could be obtained by gravity thickening for the same period. After thickening the effluent water quality in terms of TCOD, SS, and turbidity was improved by EF operation for all sludge samples. It is induced that the air bubbles entrapped in the thickened sludge play a key role in the observed improvement of sludge thickening and effluent quality.

Keywords

References

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