유입유량과 연계한 여과지 가동지수 변동 운영이 여과수 수질에 미치는 영향

Influence of Filtrate Quality by Variation of Operating Filter Number Based on Inflow

  • 김진근 (한국수자원공사 수도관리처.한국수자원공사 정읍수도서비스센터) ;
  • 이정택 (한국수자원공사 수도관리처.한국수자원공사 정읍수도서비스센터)
  • Kim, Jin-Keun (K-water, Dept. of Water Supply Operation and Maintenance, K-water Jeongeup Water Supply Service Center) ;
  • Lee, Jung-Tack (K-water, Dept. of Water Supply Operation and Maintenance, K-water Jeongeup Water Supply Service Center)
  • 투고 : 2009.07.23
  • 심사 : 2009.08.27
  • 발행 : 2009.09.30

초록

여과공정에서 수리적 충격부하로 인한 탁질누출을 방지하기 위하여, 여과지 유입량 변화에 대응하여 여과지 운영지수를 변화시키면서 여과수의 탁도 및 입자수를 고찰하였다. S 정수장은 여과지 유입량 최대/최소의 비가 2.2였으며, 이에 따라 여과속도도 변동하였다. S 정수장에서는 여과속도 변동 최소화를 위하여 여과유입수량 변동에 따라 여과지수를 변동시켰다. 여과지 유입유량 변화에 따라 가동, 휴지, 재가동을 반복하였을 경우 탁질누출은 심하지 않았다. 여과가동 누계시간이 10 h 이전이나 50 h 이후에 재가동시는 탁질누출현상이 일부 발견되었다. 이런 현상은 여재의 숙성이 충분하지 않거나 입자물질의 부착량 과다에 기인할 수 있다. 따라서 여과지를 재가동할 때는 누계여과지속시간이 10 h 이상, 50 h 미만인 여과지를 선택하는 것이 효율적인 것으로 조사되었다. 여과지 유입유량 변동에 따른 여과지수 변동은 UFRV 향상을 위한 방법으로 판단된다.

To prevent turbidity breakthrough in a depth filter caused by hydraulic shock loads, influence of turbidity and particle number in filtrate by variation of operating filter number depending on inflow change was investigated. Inflow quantity at the S water treatment plant (WTP) was varied and ratio of maximum/minimum inflow quantity was 2.2, therefore filtration velocity was also subsequently changed. The S WTP changed operating filter number depending on inflow variation to minimize change of filtration velocity. Particle breakthrough was not severe when operation system was changed, out-of-operation and re-start of filter was repeated depending on inflow quantity. Slight particle breakthrough was noticed when re-start of filter was implemented at the filter that had a cumulative filtration run time of less than 10 h or more than 50 h. This can be attributed to the inadequate ripening and over accumulation of particles on media. Therefore, it is more efficient to choose a re-starting filter basin which has cumulative filtration run time more than 10 h or less than 50 h to reduce particle breakthrough. Filter number variation depending on inflow change was proven to be a method for improvement of unit filter run volume (UFRV).

키워드

참고문헌

  1. McTigue, N. E., LeChevallier, M., Arora, H., and Clancy, J. (1998) National Assessment of Particle Removal by Filtration. AWWARF and AWWA, Denver
  2. LeChevallier, M. W., and Norton, W. D., Examining Relationship Betweeen Particle Counts, Giardia, Cryptosporidium, and Turbidity. J. AWWA, 84(12), 54-60.(1992) https://doi.org/10.1002/j.1551-8833.1992.tb05902.x
  3. Smith, J. E., and Perdek, J. M. “Assessment and management of watershed microbial contaminants.” Crit. Rev. Environ. Sci. and Tech., 34, pp. 109-139.(2004) https://doi.org/10.1080/10643380490430663
  4. Tufenki, N., Dixon, D. R., Considine, R., and Drummond, C. J., Multi-scale Cryptosporidium/sand interactions in water treatment, Wat. Res., 40, 3315-3331.(2006) https://doi.org/10.1016/j.watres.2006.07.036
  5. Emelko, M. B., Huck, P. M., and Coffey, B. M., “A review of Cryptosporidium removal by granular media filtration.”, J. AWWA, 97(12), 101-115.(2005)
  6. 환경부 (2008) 정수처리기준 등에 관한 규정(환경부고시 제 2008-60호)
  7. Amirtharajah, A., “Some Theoretical and Conceptual Views of Filtration.”, J. AWWA, 80(12), 36-46.(1988)
  8. Kim, J., Nason, J. A., and Lawler, D. F., “Influence of Surface Charge Distributions and Particle Size Distributions on Particle Attachment in Granular Media Filtration.”, Environ. Sci. Technol., 42(7), pp. 2557-2562.(2009)
  9. Ahmad, R. Amirtharajah, A., Detachment of Particles During Biofilter Backwashing. J. AWWA, 90(12), 74-85.(1998)
  10. Bergendahl, J., and Grasso, D., Prediction of Colloid Detachment in a Model Porous Media: Thermodynamics. AIChE Journal, 45(3), 475-484.(1999) https://doi.org/10.1002/aic.690450305
  11. Bergendahl, J., and Grasso, D., “Prediction of colloid detachment in a model porous media: hydrodynamics.”, Chem. Eng. Sci., 55, 1523-1532.(2000) https://doi.org/10.1016/S0009-2509(99)00422-4
  12. Adin, A., and Rebhun, M.,“ Deep-Ded Filtration: Accumulation-Detachment Model Parameters.”, Chem. Eng. Sci., 42(5), 1213-1219.(1987) https://doi.org/10.1016/0009-2509(87)80072-6
  13. Sharma, M. M., Chamoun, H., Sarma, D. S., and Schechter, R. S., “Factors Controlling the Hydrodynamic Detachment of Particles from Surfaces.”, J. Colloid Interface Sci., 149(1), 121-134.(1992) https://doi.org/10.1016/0021-9797(92)90398-6
  14. Ryan, J. N., and Gschwend, P. M., “Effects of Ionic Strength and Flow Rate on Colloid Release: Relating Kinetics to Intersurface Potential Energy.”, J. Colloid Interface Sci., 164(1), 21-34.(1994) https://doi.org/10.1006/jcis.1994.1139
  15. Bai, R., and Tien, C., “Particle Detachment in Deep Bed Filtration.”, J. Colloid Interface Sci., 186(2), 307-317.(1997) https://doi.org/10.1006/jcis.1996.4663
  16. Kim, J., and Lawler, D. F., “Particle detachment during hydraulic shock loads in granular media filtration.”, Wat. Sci. and Tech1910., 53(7), pp. 177-184.(2006) https://doi.org/10.2166/wst.2006.222
  17. Amburgey, J. E., “Optimization of the extended terminal subfluidization wash (ETSW) filter backwashing procedure.”, Water Res., 39(2-3), 314-330.(2005) https://doi.org/10.1016/j.watres.2004.09.020
  18. AWWARF, Filter Maintenance and Operations Guidance Manual. AWWARF and AWWA, Denver.(2002)
  19. Kawamura, S., Integrated Design and Operation of Water Treatment Facilities. John Wiley & Sons, Inc., New York,.(2002)
  20. McDowell-Boyer, L. M., “Chemical Mobilization of Micron-Sized Particles in Saturated Porous Media under Steady Flow Conditions.”, Environ. Sci. Tech., 26(3), 586-593.(1992) https://doi.org/10.1021/es00027a023
  21. Han, J., Fitzpatrick, C. S., and Wetherill, A., “The impact of flow surges on rapid gravity filtration.”, Wat. Res., 43, 1171-1178.(2009) https://doi.org/10.1016/j.watres.2008.12.003