Integrated Method to Determine the Sphericity of Filter Media

여과지에서 여재 원형도 결정 방법에 대한 연구

  • 정원석 (한국수자원공사 과천권관리단) ;
  • 최승일 (고려대학교 환경시스템공학과)
  • Received : 2005.06.21
  • Accepted : 2005.09.12
  • Published : 2005.10.15

Abstract

The method to decide media sphericity on the filter has been investigated. The sphericity, the ratio of the surface area of an equal volume sphere to the real surface area of the particles, is one of major physical characters of media affecting the bed expansion during backwash. The media in each treatment plant may have different sphericity, and the sphericity of the media in the filter may be changed as backwashing has been conducted regularly for a long time. Media from twelve water treatment plants under KOWACO have been collected and selected to insure various and practical sphericities. The sphericity of each media has been calculated by using well known equations. For example, Kozeny equation, Dahmarajah equation and so on. The experiment results have indicated that the sphericity of each water treatment plant is different. Although the sphericity values measured by different methods were turned out to be diverse values, the order in the magnitude seemed to be the same. The sphericity values of sand media were in the range of 0.71-0.82 and those of anthracite were placed between 0.49 and 0.56 by the Dharmarajah equation.

Keywords

References

  1. 김상구 (1993 ) 급속여과법에 의한 정수처리 특성에 관한 연구, 동아대학교 대학원 박사학위논문
  2. 박영숙 (1995) 모래의 입도분포가 여과효율에 미치는 영향, 한양대학교 대학원 박사학위논문
  3. 최승일, 최준석 (1996) 여과재의 종류에 따른 최소유동상 속도 및 팽창에 관한 연구, 상하수도학회지, 10(2), pp. 55
  4. 최승일, 원동찬 (1998) 침강속도에 의한 이중여재 입경 선정 방볍, 수처리기술, 6(2), pp.53-62
  5. Cleasby, J.L. (1977) Filtration I - Hydraulic Considerations and Backwashing Operations in Granular Bed Filtration, Proceedings Nineteenth Annual Public Water Supply Engineers' Conference - Water Treatment, Part II; Department of Civil Engineering - University of Illinois at Urbana-Champaign, American Water Works Association, Illinois Environmental Protection Agency, and Illinois Section AWWA. pp. 7-22, April 5-7
  6. Dharmarajah, A.H. (1982) Effect of Particle Shape on Prediction of Velocity-Void age Relationship in Fluidized Solid Liquid Systems., Ph.D dissertation., Iowa State University
  7. Muslu, Y. (1987) A New Approach to the Prediction of Fluidization of Filter Media, Teknik Universite, Istanbul, Turkey, Water Research, 21(9),1053-1060 https://doi.org/10.1016/0043-1354(87)90026-1