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A Study on Hydraulic Modifications of Low-Pressure Membrane Inlet Structure with CFD and PIV Techniques

CFD와 PIV 기법을 이용한 저압막 유입부 수리구조 개선에 관한 연구

  • Oh, Jeong Ik (LH Institute) ;
  • Choi, Jong-Woong (K-water Institute) ;
  • Lim, Jae-Lim (K-water Institute) ;
  • Kim, Donggil (Department of Civil Engineering and Engineering Research Institute, Gyeongsang National University) ;
  • Park, No-Suk (Department of Civil Engineering and Engineering Research Institute, Gyeongsang National University)
  • Received : 2015.11.04
  • Accepted : 2015.11.16
  • Published : 2015.11.30

Abstract

This study was conducted to suggest hydraulic modification for improving evenness of inlet flow distribution into side stream type low-pressure MF (microfiltration) module using CFD (computational fluid dynamics) simulation and PIV (particle image velocimetry) techniques. From the results of CFD simulation for various typed inlet structure, it was investigated that installing internal orifice baffle in inlet the distribution channel could improve the evenness of inlet flow distribution over about 40%. Also, from the results of PIV measurements which were carried out for verifying the CFD simulation, it was observed that the momentum of the water body coming from the opposite side of the inlet was relatively larger. This momentum would generate strong shear force in the near of inlet side wall. On the other hands, occurrence of dead zone and eddy flow was confirmed in the opposite side.

본 연구에서는 CFD 모사와 PIV 기법을 이용하여 실규모의 사이드 스트림 방식의 막 모듈을 대상으로 유입부의 수리구조를 개선하여 모듈로 유입되는 유입 유량을 수직으로 균등하게 분포시킬 수 있는 방안을 제시하고 이를 실험적으로 검증하고자 하였다. 사이드 스트림 방식의 막 모듈을 대상으로 유입 유량을 수직으로 균등하게 분포시킬 수 있는 방안을 CFD로 설계한 결과, 내부 유입 수리구조에 유공 격벽을 설치함으로써 모듈내로의 유입유량은 표준편차 기준으로 약 40% 정도 감소됨을 확인하였다. 또한 CFD 결과를 검증하고 사이드 스트림 막 모듈의 편중된 오염의 원인을 조사하기 위해 수행된 입자영상유속 측정 결과로부터 유입구 반대편 유공에서 막 모듈 내부로 들어오는 수체의 유속이 상대적으로 커 수체의 모멘텀이 유입구 측벽에 강한 전단력을 발생하지만 유입구 반대 측벽에서는 사류가 형성됨을 확인하였다.

Keywords

References

  1. Li, Y. L. and Tung, K. L., "CFD simulation of fluid flow through spacer-filled membrane module: selecting suitable cell types for periodic boundary conditions," Desalination, 233, 351-358(2008). https://doi.org/10.1016/j.desal.2007.09.061
  2. Owen, G., Bandi, M., Howell, J. A. and Churchouse, S. J., "Economic assessment of membrane process for water and waste water treatment," J. Membr. Sci., 102, 77-91(1995). https://doi.org/10.1016/0376-7388(94)00261-V
  3. Guo, H., Wyart, Y., Perot, J., Nauleau, F. and Moulin, P., "Low-pressure membrane integrity tests for drinking water treatment: A review," Water Res., 44, 41-57(2010). https://doi.org/10.1016/j.watres.2009.09.032
  4. David, H., Furukawa, P. E. and Ch, E., "NWRI Final Project Report: a Global Perspective of Low Pressure Membrane," USA, California(2008).
  5. Brehant, A., Glucina, K., Lemoigne, I. and Laine, J. M., Risk Mangement Approach for Monitoring UF Membrane Integrity and Experimental Validation using MS2-phages. IWA World Water Congress, Austria Vienna(2008).
  6. Huang, H., Schwab, K. and Jacangelo, J. G., "Pretreatment for Low Pressure Membrane in Water Treatment: A Review," Environm. Sci. Technol., 43(9), 3011-3019(2009). https://doi.org/10.1021/es802473r
  7. Zhu, B. T., Clifford, D. A. and Chellam, S., "Virus removal by iron coagulation-microfiltration." Water Res., 39(20), 5153-5161(2005). https://doi.org/10.1016/j.watres.2005.09.035
  8. Yan, M., Wang, D., Ni, J., Qu, J., Chow, C. W. K. and Liu, H., "Mechanism of natural organic matter removal by polyaluminum chloride: Effect of coagulant particle size and hydrolysis kinetics," Water Res., 42(3), 3361-3370(2008). https://doi.org/10.1016/j.watres.2008.04.017
  9. Kim, J., Cai, Z. and Benjamin, M. M., "Effects of adsorbents on membrane fouling by natural organic matter," J. Membr. Sci., 310(1-2), 356-364(2008). https://doi.org/10.1016/j.memsci.2007.11.007
  10. Clark, M. M., Ahn, W. Y., Li, X., Sternisha, N. and Riley, R. L., "Formation of polysulfone colloids for adsorption of natural organic foulants," Langmuir, 21(16), 7207-7213 (2005). https://doi.org/10.1021/la050186l
  11. Plummer, J. D. and Edzwald, J. K., "Effects of chlorine and ozone on algal cell properties and removal of algae by coagulation," J. Water Supply Res. Technol.-AQUA-, 51(6), 307-318(2002). https://doi.org/10.2166/aqua.2002.0027
  12. Wang, X., Wang, L., Liu, Y. and Duan, W., "Ozonation pretreatment for ultrafiltration of the secondary effluent," J. Membr. Sci., 287(2), 187-191(2007). https://doi.org/10.1016/j.memsci.2006.10.016
  13. Koh, M., Clark, M. A. and Howe, K. J., "Filtration of lake natural organic matter: Adsorption capacity of a polypropylene microfilter," J. Membr. Sci., 256(1-2), 169-175 (2005). https://doi.org/10.1016/j.memsci.2005.02.016
  14. Sakol, D. and Konieczny, K., "Application of coagulation and conventional filtration in raw water pretreatment before microfiltration membranes," Desalination, 162(1-3), 61-73 (2004). https://doi.org/10.1016/S0011-9164(04)00028-1
  15. Park, N. S., Kim, S., Lee, Y. and Wang C., "Effects of Longitudinal Baffles on Particles settling in a Sedimentation Basin," Water Sci. Technol., 69(6), 1212-1218(2014). https://doi.org/10.2166/wst.2013.818
  16. Kim, S., Park, N. S., Jeong, W. and Wang, C., "Process control systems of granular media filter considering daily flow-rate fluctuation," Desalination and Water Treat., 51(37-39), 6978-6984(2013). https://doi.org/10.1080/19443994.2013.797696
  17. Lee, A., Park, N. S., Kim, S. and Kim, N., "Physical modification to improve a channel's flow distribution," Korean J. Chem. Eng., 29(2), 201-208(2012). https://doi.org/10.1007/s11814-011-0163-9
  18. ANSYS, ANSYS CFX Tutorials, ANSYS, Inc., Southpointe U.S.A(2009).
  19. Rajendran, V. P. and Patel, V. C., "Measurement of Vortices in Model Pump Intake Bay by PIV," J. Hydraulic Eng., ASCE, 126(5), 322-334(2000). https://doi.org/10.1061/(ASCE)0733-9429(2000)126:5(322)

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