Effect of Media Grain Shape on Particle Straining during Filtration
Publication: Journal of Environmental Engineering
Volume 133, Issue 2
Abstract
This paper investigates how straining mechanisms of angular media (crushed limestone) provide improved filtration performance compared to rounded media (river stone). Columns of granular media were set in resin, sectioned, photographed, and digitized to produce a three-dimensional model of pore space geometry. This process was repeated for four filter media, each representing different grain shapes or packing densities. From measured pore throat distributions, a stepwise particle movement model was used to estimate the maximum volume of particles that could be stored in the bulk of the filter media. The results showed that the more angular the media, the wider the range of particle sizes that could be strained in the bulk of the filter. The stepwise model was applied only to individual particles; trapping of colloidal particles was not considered. However, when individual particles are too small to be strained, the same pore throat trapping contributes to the physical capture of avalanches and flocculates. Thus the findings of this work are relevant to deep bed filtration applications where headloss results from straining, such as storm-water best management practices or soil filters.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
Special thanks are given to the anonymous reviewers for their helpful criticisms.
References
Barton, J. (2004). “The effect of media grain shape on the physical capture of particles in a filter bed.” Ph.D. dissertation, Univ. of Cincinnati, Cincinnati.
Barton, J., and Buchberger, S. G. (2003). “Geometrical analysis of small sand piles.” Phys. Rev. E, 68 011303.
Bhati, S. K., and Soliman, A. F. (1990). “Frequency distribution of void ratio of granular materials determined by image analyzer.” Soils Found., 30(1), 1–16.
Cox, E. P. (1927). “A method of assigning numerical and percentage values to the degree of roundness of sand grains.” J. Paleontology, 1(3), 179–183.
Dodds, J. A. (1980). “The porosity and contact points in multicomponent random sphere packings calculated by a simple geometric model.” J. Colloid Interface Sci., 77(2), 317–327.
Dullien, F. A. L. (1991). “Characterization of porous media.” Transp. Porous Media, 6(5–6), 581–606.
Evans, G., Dennis, P., Cousins, M., and Campbell, R. (2002). “Use of recycled crushed glass as a filtration medium in municipal potable water treatment plants.” Water Sci. Technol., 3(5–6), 9–16.
Graton, L. C., and Fraser, H. J. (1935). “Systematic packing of spheres—With particular relation to porosity and permeability.” J. Geol., 43(8), 785–909.
Gray, W. A. (1968). The packing of solid particles, Chapman and Hall LTD., London, 28 and 50.
Hwang, K. J., Wu, Y. S., and Lu, W. M. (1997). “Effect of the size distribution of spheroidal particles on the surface structure of a filter cake.” Powder Technol., 91(2), 105–113.
Indraratna, B. N., and Locke, M. (2001). “Analytical modeling and experimental verification of granular filter behavior.” Filters and drainage in geotechnical and environmental engineering, W. Wolski and J. Miynarek, eds., Balkema, Rotterdam, The Netherlands, 3–25.
Janoo, V. C. (1998). “Quantification of shape, angularity, and surface texture of base course materials.” NTIS 19980128 092, U.S. Army Cold Regions Research and Engineering Laboratory, Hanover, N.H.
Kweicien, M. J. (1987). “Determination of pore size distribution of Berea sandstone through three-dimensional reconstruction.” MASc thesis, Univ. of Waterloo, Waterloo, Ont., Canada.
Locke, M., Indraratna, B., and Adikari, G. (2001). “Time dependent particle transport through granular filters.” J. Geotech. Geoenviron. Eng., 127(6), 521–529.
Podczeck, F. (1997). “A shape factor to assess the shape of particles using image analysis.” Powder Technol., 93(1), 47–53.
Rege, S. D., and Fogler, H. S. (1987). “Network model for straining dominated particle entrapment in porous media.” Chem. Eng. Sci., 42(7), 1553–1564.
Reyes, S. C., and Iglesia, E. (1991). “Monte Carlo simulations of structural properties of packed beds.” Chem. Eng. Sci., 46(4), 1089–1099.
Sakthivadivel, R. (1966). “Theory and mechanism of filtration of non-colloidal fines through a porous medium.” Rep. No. HEL 15-5, Hydraulic Engineering Laboratory, Univ. of Calif., Berkeley, Berkeley, Calif.
Sakthivadivel, R. (1969). “Clogging of a granular porous medium by sediment.” Rep. No. HEL 15-7, Hydraulic Engineering Laboratory, Univ. of Calif., Berkeley, Berkeley, Calif.
Scott, G. D. (1960). “Packing of spheres.” Nature (London), 188(4754), 908–909.
Silveira, A. (1965). “An analysis of the problem of washing through in protective filters.” Proc., 6th Int. Conf. Soil Mechanics and Foundation Engineering, Vol. 2, 551–555.
Suthaker, S., Smith, D. W., and Stanley, S. J. (1995). “Evaluation of filter media for upgrading existing filter performance.” Environ. Technol., 16(7), 625–643.
Trussel, R. R., Trussell, A. R., Lang, J. S., and Tate, C. H. (1980). “Recent developments in filtration system design.” J. Am. Water Works Assoc., 12(12), 705–710.
Viklander, M. (1998). “Particle size distribution and metal content in street sediments.” J. Environ. Eng., 124(8), 761–766.
Witt, K. J. (1993). “Reliability study of granular filters.” Filters in geotechnical and hydraulic engineering, J. Brauns, U. Schuler, and M. Heibaum, eds., Balkema, Rotterdam, The Netherlands, 35–41.
Wittman, L. (1979). “The process of soil-filtration—Its physics and the approach in engineering practice.” Design parameters in geotechnical engineering, Vol. 1, BGS, London, 303–310.
Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 133 • Issue 2 • February 2007
Pages: 211 - 219
Copyright
© 2007 ASCE.
History
Received: May 20, 2004
Accepted: Jun 23, 2006
Published online: Feb 1, 2007
Published in print: Feb 2007
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.