상하수도학회지 (Journal of Korean Society of Water and Wastewater)

  • 제21권6호
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  • Pages.717-726
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  • 2007
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  • 1225-7672(pISSN)
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  • 2287-822X(eISSN)
대한상하수도학회 (The Korean Society of Water and Wastewater)
권호 표지

관내 입자 재응집에 의한 케이크 저항의 감소

Reduction of Cake Resistance by Floc Reaggregation in a Membrane-Feed-Pipe

  • 투고 : 2007.09.10
  • 심사 : 2007.12.06
  • 발행 : 2007.12.15
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초록

Fully-grown flocs in a mixing tank of membrane filtration with dead-end membrane are ruptured while passing through a pump and the ruptured flocs are aggregated again in a Membrane-Feed-Pipe (MFP). To look at more details, this study tries to relate the reaggregation to a parameter of mixing intensity in MFP, i.e., G-value. The G-value is a function of Reynolds number, pipe diameter, friction factor and average velocity in MFP. To deal with polydispersity condition, we develop a representative particle size called in this study EDPD (Effective Diameter for Polydispersity condition in Dead-end filtration). The experimental results show that as the G-value increases, the EDPD decreases and also the cake resistance increases. Through comparison between EDPD and cake resistance, these results show that cake resistances are controlled by reaggregation phenomenon in MFP. The effect of detention time in MFP, however, does not affect the reaggregation of the broken flocs as G-values are increased.

키워드

과제정보

연구 과제 주관 기관 : 한국학술진흥재단

참고문헌

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