Journal of Korean Society on Water Environment (한국물환경학회지)

Korean Society on Water Environment (한국물환경학회)
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Investigation on Flocculi-floc Interaction and Flocculation in Extracellular Polymeric Substances, Ionic Species and Clay-containing Suspension

생체고분자물질 농도와 이온강도에 따른 점토입자 현탁액의 응집핵-응집체 이군집 응집 특성 연구

  • Kim, Jae In (Department of Disaster Prevention and Environmental Engineering, Kyungpook National University) ;
  • Lee, Byung Joon (Department of Disaster Prevention and Environmental Engineering, Kyungpook National University)
  • Received : 2020.03.20
  • Accepted : 2020.05.11
  • Published : 2020.05.30
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Abstract

Bimodal flocculation describes the aggregation and breakage processes of the flocculi (or primary particles) and the flocs in the water environment. Bimodal flocculation causes bimodal size distribution with the two separate peaks of the flocculi and the flocs. Extracellular polymeric substances and ionic species common in the water environment increase the occurrence of bimodal flocculation and flocculi-floc size distribution, under the flocculation mechanisms of electrostatic attraction and polymeric bridging. This study investigated bimodal flocculation and flocculi-floc size distribution, with respect to the extracellular polymeric substance concentration and ionic strength in the kaolinite-containing suspension. The batch flocculation tests comprising 0.12 g/L of kaolinite showed that the highest flocculation potential occurred at the lowest xanthan gum (as extracellular polymeric substances) concentration, under all the ionic strengths of 0.001, 0.01, and 0.1 M NaCl. Also, it was important to note that the higher ionic strength resulted in the higher flocculation potential, at all the xanthan gum concentrations. The bimodal flocculation and flocculi-floc size distribution became apparent in the experimental conditions, which had low and intermediate flocculation potential. Besides the polymeric bridging flocculation, steric stabilization increased the flocculi mass fraction against the floc mass fraction, thereby developing the bimodal size distribution.

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References

  1. Bache, D. H. and Gregory, R. (2007). Flocs in water treatment, IWA publishing, London, UK.
  2. Bolto, B. and Gregory, J. (2007). Organic polyelectrolytes in water treatment, Water Research, 41(11), 2301-2324. https://doi.org/10.1016/j.watres.2007.03.012
  3. Garcia-Ochoa, F., Santos, V. E., Casas, J. A., and Gomez, E. (2000). Xanthan gum: production, recovery, and properties, Biotechnology Advances, 18(7), 549-579. https://doi.org/10.1016/S0734-9750(00)00050-1
  4. Heintzenberg, J. (1994). Properties of the log-normal particle size distribution, Aerosol Science and Technology, 21(1), 46-48. https://doi.org/10.1080/02786829408959695
  5. Hogg, R. (2013). Bridging flocculation by polymers, KONA Powder and Particle Journal, 30, 3-14. https://doi.org/10.14356/kona.2013005
  6. Kang, X., Bate, B., Chen, R. P., Yang, W., and Wang, F. (2019). Physicochemical and mechanical properties of polymer amended kaolinite and fly ash-kaolinite mixtures, Journal of Materials in Civil Engineering, 31(6), 04019064. https://doi.org/10.1061/(asce)mt.1943-5533.0002705
  7. Lee, B. J., Toorman, E., Molz, F. J., and Wang, J. (2011). A two-class population balance equation yielding bimodal flocculation of marine or estuarine sediments, Water Research, 45(5), 2131-2145. https://doi.org/10.1016/j.watres.2010.12.028
  8. Lee, B. J., Hur, J., and Toorman, E. A. (2017). Seasonal variation in flocculation potential of river water: Roles of the organic matter pool, Water, 9(5), 335. https://doi.org/10.3390/w9050335
  9. Lee, B. J., Schlautman, M. A., Toorman, E., and Fettweis, M. (2012). Competition between kaolinite flocculation and stabilization in divalent cation solutions dosed with anionic polyacrylamides, Water Research, 46(17), 5696-5706. https://doi.org/10.1016/j.watres.2012.07.056
  10. Lu, C. and Pelton, R. (2001). PEO flocculation of polystyrene-core poly (vinylphenol)-shell latex: an example of ideal bridging, Langmuir, 17(25), 7770-7776. https://doi.org/10.1021/la010893o
  11. Manning, A. J., Bass, S. J., and Dyer, K. R. (2006). Floc properties in the turbidity maximum of a mesotidal estuary during neap and spring tidal conditions, Marine Geology, 235(1-4), 193-211. https://doi.org/10.1016/j.margeo.2006.10.014
  12. Oyegbile, B., Ay, P., and Narra, S. (2016). Flocculation kinetics and hydrodynamic interactions in natural and engineered flow systems: A review, Environmental Engineering Research, 21(1), 1-14. https://doi.org/10.4491/eer.2015.086
  13. Pillai, J. (1997). Flocculants and coagulants: the keys to water and waste management in aggregate production, Condensed version appeared in December issue of Stone Review, Nalco Company.
  14. Passow, U. (2002). Transparent exopolymer particles (TEP) in aquatic environments, Progress in Oceanography, 55(3-4), 287-333. https://doi.org/10.1016/S0079-6611(02)00138-6
  15. Salopek, B., Krasic, D., and Filipovic, S. (1992). Measurement and application of zeta-potential, Rudarsko-geolosko-naftni zbornik, 4(1), 147.
  16. Sanchez-Martin, J., Beltran-Heredia, J., and Peres, J. A. (2012). Improvement of the flocculation process in water treatment by using Moringa oleifera seeds extract, Brazilian Journal of Chemical Engineering, 29(3), 495-502. https://doi.org/10.1590/S0104-66322012000300006
  17. Smith, I. H. and Pace, G. W. (1982). Recovery of microbial polysaccharides, Journal of Chemical Technology and Biotechnology, 32(1), 119-129. https://doi.org/10.1002/jctb.5030320116
  18. Tan, X. L., Zhang, G. P., H ang, Y. I. N., and FURUKAWA, Y. (2012). Characterization of particle size and settling velocity of cohesive sediments affected by a neutral exopolymer, International Journal of Sediment Research, 27(4), 473-485. https://doi.org/10.1016/S1001-6279(13)60006-2
  19. Thomas, J. C. (1987). The determination of log normal particle size distributions by dynamic light scattering, Journal of Colloid and Interface Science, 117(1), 187-192. https://doi.org/10.1016/0021-9797(87)90182-2
  20. Villacorte, L. O., Ekowati, Y., Calix-Ponce, H. N., Schippers, J. C., Amy, G. L., and Kennedy, M. D. (2015). Improved method for measuring transparent exopolymer particles (TEP) and their precursors in fresh and saline water, Water research, 70, 300-312. https://doi.org/10.1016/j.watres.2014.12.012
  21. Wang, Y. P., Voulgaris, G., Li, Y., Yang, Y., Gao, J., Chen, J., and Gao, S. (2013). Sediment resuspension, flocculation, and settling in a macrotidal estuary, Journal of Geophysical Research: Oceans, 118(10), 5591-5608. https://doi.org/10.1002/jgrc.20340
  22. Watanabe, M., Suzuki, Y., Sasaki, K., Nakashimada, Y., and Nishio, N. (1999). Flocculating property of extracellular polymeric substance derived from a marine photosynthetic bacterium, Rhodovulum sp. Journal of Bioscience and Bioengineering, 87(5), 625-629. https://doi.org/10.1016/S1389-1723(99)80125-X
  23. Wotton, R. S. (2011). EPS (Extracellular Polymeric Substances), silk, and chitin: vitally important exudates in aquatic ecosystems, Journal of the North American Benthological Society, 30(3), 762-769. https://doi.org/10.1899/10-120.1
  24. Zhang, J., Shen, X., Zhang, Q., Maa, J. P. Y., and Qiao, G. (2019). Bimodal particle size distributions of fine-grained cohesive sediments in a settling column with oscillating grids, Continental Shelf Research, 174, 85-94. https://doi.org/10.1016/j.csr.2019.01.005