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Resuspension of Cohesive Sediment under Presence of Gas Bubbles

기포에 의한 점착성 퇴적물의 부유

  • Kim, Jong-Woo (Water Resources Research Dept., Korea Institute of Construction Technology)
  • 김종우 (한국건설기술연구원 수자원연구부)
  • Published : 2005.04.01

Abstract

The elimination and erosion of cohesive sediments in port and reservoir water can so far be processed only with mechanical evacuation methods under extreme energy expenditure. The so-called flushing jets do not serve the purpose because they cannot set the material spaciously in motion despite high shear stresses at the bed. Therefore this study aims to examine the resuspension of the deposited fine material($Al_{2}O_3$) under presence of gas bubbles in order to decreased cohesive sediments in multipurpose dam, port and lakes. In the case of laboratory trial important parameters considered are supplied amount of air and the consolidation time of the solid materials. With increasing gas content alumina remains in suspension at high pH values in the laboratory test, where the particles fall mote rapidly without air addition.

항만 및 저수지에서 점착성 퇴적물의 침식 및 제거는 극도로 큰 에너지를 동반한 기계적인 배출방법으로 단지 가능할 수 있다. 소위 분사방법은 높은 전단력에도 불구하고 점착성 퇴적물을 움직이게 하는데 실효를 거두지 못하고 있다. 그러므로 본 연구는 다목적댐, 항만 그리고 호수 등에서 퇴적된 점착성 미립자들을 저감시키기 위해 기포 투입으로 침전된 미립자($Al_{2}O_3$)의 부유현상을 실험하는데 목적을 두고 있다. 실험을 통해 중요한 매개변수는 투입된 기포의 양과 침전된 퇴적물의 응고시간인 것을 알 수 있었다. 기포 투입없이 높은 pH값에서 빨리 침전되는 미립자 퇴적물(alumina)은 기포의 증가로 입자의 부유현상이 일어난다.

Keywords

References

  1. Adu-Wusu, C., Yanful, E. K., and Mian, M. H.(2001). 'Field evidence of resuspension in a mine tailings pond.' Con. Geotech J. Vol. 38, pp. 796-808 https://doi.org/10.1139/cgj-38-4-796
  2. Been, K., and Sills G. C. (1981). Self-weight consolidation of soft soils: an experimental and theoretical study. Geotechnique Vol. 31, No. 4, pp. 519-535 https://doi.org/10.1680/geot.1981.31.4.519
  3. Chapra, S. C. (1997). Surface Water-Quality Modeling. McGraw-Hill Book Company, pp. 295-297
  4. De Wit, P. J. (1995). Liquefaction of cohesive sediments caused by waves. Ph.D. dissertaion, Delft University of Technology
  5. Kato. Y., Nishiwiaki, A., Fukuda, T., and Tanaka, S. (1972). 'The Behavior of Suspended Solid Particles and Liquid in Bubble Columns.' Journal Chem. Eng. Japan, Bd. 5, Nr.2, S.112-118 https://doi.org/10.1252/jcej.5.112
  6. Krone, R. B. (1962). Flume Studies of the Transport of Sediment in Estuarial Shoaling Processes. Final Rep., Hydr. Engr. Lab. and Sanitary Engr. Res. Lab., Univ. of California, Berkeley, June
  7. Li. Y., and Mehta, A. J. (1994). 'Mud fluidization by water waves.'4th Nearshore and Estuarine Cohesive Sediment Transport Conference, Intercoh '94; Wallingford, England; 11. 15. Juli
  8. Mehta, A. J. (1986). Characterization of cohesive sediment properties and transport processes in estuaries, In: A.J. Mehta(ed) Estuarine Cohesive Sediment Dynamics. Springer Verlag. pp. 290-325
  9. Pralle, N., Kulzer, M., and Gudehus, G. (2002). 'Experimental evidence on the role of gas in sediment liquefaction and mud volcanism.' Geological Society of London, Special Publication Series https://doi.org/10.1144/GSL.SP.2003.216.01.11
  10. Smith, D. N., and Ruether, A. J. (1985). 'Dispersed Solid Dynamics in a Slurry Bubble Column.' Chem. Eng. Sci., Vol. 4(5), pp. 741 https://doi.org/10.1016/0009-2509(85)85027-2
  11. Teisson, C. (1991): 'Cohesive Suspended Sediment Transport: Feasibility and Limitations of Numerical Modelling.' Journal of Hydraulic Research, Vol. 29, no. 6, pp. 755-769 https://doi.org/10.1080/00221689109498957
  12. Van Leussen, W. (1994). Estuarine Macroflocs and their Role in Fine-grained Sediment Transport. Ph.D Thesis, University Utrecht
  13. Deckwer, W. D., und Schumpe, A. (1985). 'Blasensaelen - Erkenntnisstand und Entwick-lungstendenzen.' Chem. -Ing. Tech. Vol. 57, S. 754-767, Deutschland(Germany) https://doi.org/10.1002/cite.330570909
  14. Gudehus, G., and Kulzer, M. (2002). Einfluss von Ionen und Gasblasen auf die Kollapsneigung feinstkoerniger Boeden. Geotechnik 25, Nr. 1, pp. 12-2, Deutschland(Germany)
  15. Kohler, H. J. (1997). Porenwasserdruckausbreitung im Boden, Messverfahren und Berechnungsansatze. Mitteilungsblatt der Bundesanstalt fur Wasserbau, Nr. 75, Deutschland(Germamy)
  16. Mihopulos, J. (1995). Wechselwirkung Flockenbildung Flockenabtrennng unter Berucksichtigung der Durchstromungsmuster in Sedimentations- und Flotationsbecken. Institut fur Siedlungswasser-wirtschaft, Universitat Karlsruhe, Heft 72, Deutschland(Germany)
  17. Osmann-Sigg, G. K. (1982). Kolloidale und suspendierte Teilchen in naturlichen Gewassern. Partikelgrossenverteilung und naturliche Koagulation im Zurichsee, Zurich, ETH, Diss
  18. Spork, V. (1997): Erosionsverhalten feinet Sediment und ihre biogene Stabilisierung. Mitteilungen des Instituts fur Wasserbau und Wasserwirtschaft, RWTH Aachen, Band 114 Deutschland