상하수도학회지 (Journal of Korean Society of Water and Wastewater)

  • 제22권3호
  • /
  • Pages.281-288
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  • 2008
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  • 1225-7672(pISSN)
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  • 2287-822X(eISSN)
대한상하수도학회 (The Korean Society of Water and Wastewater)
권호 표지

인라인 주입방식의 최초응집이 케이크 저항에 미치는 영향

Effect of cake resistance by first-aggregation of in-line injection system

  • 투고 : 2008.02.18
  • 심사 : 2008.04.28
  • 발행 : 2008.06.15
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초록

Cake resistance is influenced by floc size deposited on membrane surface. Enlarging floc size can reduce cake resistance. The small particles are enlarged by coagulation and flocculation process in conventional mixing tank at membrane filtration system. Fully-grown flocs for reducing the cake resistance, however, are ruptured while passing through a pump. In light of this fact, this study aims to experimentally look at the reaggregation phenomenon of mixing system. In addition, reaggregation phenomenon of mixing system is compared with first-aggregation of in-line injection system in which coagulant is injected just before a pump. These results suggest that first-aggregation of in-line injection system is better than reaggregation of mixing system for G-value above $3100sec^{-1}$. Since G-value in pipe of actual membrane filtration system are usually larger than $3100sec^{-1}$. The performance of in-line injection system is expected to be better than the conventional mixing tank system.

키워드

과제정보

연구 과제 주관 기관 : 한국학술진흥재단

참고문헌

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