Journal of Korean Society of Water and Wastewater (상하수도학회지)

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

Improvement of Activated Sludge Dewaterability by Electro-flotation

전해부상을 이용한 활성슬러지의 탈수성 향상

  • 최영균 (대구대학교 환경공학과) ;
  • 박병주 (대구대학교 환경공학과) ;
  • 박민정 (대구대학교 환경공학과) ;
  • 김윤중 (서울대학교 지구환경시스템공학부) ;
  • 정태학 (서울대학교 지구환경시스템공학부)
  • Received : 2006.04.28
  • Accepted : 2006.08.31
  • Published : 2006.10.15
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Abstract

Electro-flotation(EF), a novel sludge thickening method, could improve the dewaterability of activated sludge. The gas(microbubbles) generated during EF decreased the solid-liquid separation time below 1/5 of the time required for gravity sedimentation. In addition, over 90% of the sludge volume reduction could be achieved by EF although the settling characteristics of the sludge was very poor. The SRF(specific resistance to filtration) of the thickened sludge by EF was much lower than that of the sludge thickened by gravity sedimentation. The SRF of the thickened sludge decreased exponentially with increase of gas generation rate of the EF system. Gas generation rate could be controlled by varying the current density of the electrode. Degasing of the microbubbles by vigorous mixing of the thickened sludge layer deteriorated the dewaterability of the sludge. Therefore, it is obvious that the gas bubbles entrapped in the thickened sludge play a key role in the observed dewaterability improvement.

Keywords

References

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