Role of Short-Range Forces in Particle Detachment during Filter Backwashing
This article has a reply.
VIEW THE REPLYPublication: Journal of Environmental Engineering
Volume 121, Issue 12
Abstract
Considerable research on the process of filter backwashing with fluidization has been done during the last two decades, but there is little fundamental understanding of the mechanisms of particle detachment from filter media. The overall goal of the research reported in this study is to gain a fundamental understanding of the mechanisms by which colloidal-sized particles detach from larger grains. The theoretical part of this study has focused on calculating the interaction forces between a single particle and a collector surface coated with a deposited layer. The interaction forces that would control particle detachment include van der Waals attractive forces, electrical double-layer interactive forces, Born repulsive forces, and structural forces. The experimental studies were performed on laboratory scale model systems with well-defined spherical particle suspensions. Latex particles (5 μm) were filtered in a packed bed column of glass beads. The detachment of particles during filter backwashing under fluidization conditions was studied in relation to the chemical characteristics of the backwash water. The experimental results indicated that higher pH and lower ionic strength enhance detachment during backwashing. Theoretical force calculations based on Derjaguin, Landau, Verwey, and Overbeek (DLVO) theory alone could not explain detachment behavior. Inclusion of short-range forces in the calculations qualitatively explains the experimental results.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Amirtharajah, A., and Giourgas, A. J. (1981). “Theory for particle detachment during backwashing of filters.”Proc., Int. Symp. on Applications of Fluid Mech. and Heat Transfer to Energy and Envir. Problems.
2.
Amirtharajah, A.(1978). “Optimum backwashing of sand filters.”J. Envir. Engrg. Div., ASCE, 104(5), 917–932.
3.
Amirtharajah, A.(1988). “Some theoretical and conceptual views of filtration.”J. AWWA, 80(12), 36–46.
4.
Amirtharajah, A., and Raveendran, P.(1993). “Mechanisms of detachment of colloids from sediments and sand grains.”Colloids and Surfaces A: Physicochemical and Engrg. Aspects, Amsterdam, The Netherlands, 73, 211–226.
5.
Amirtharajah, A., and Wetstein, D. P.(1980). “Initial degradation of effluent quality during filtration.”J. AWWA, 72(9), 518–524.
6.
Churaev, N. V., and Derjaguin, B. V.(1985). “Inclusion of structural forces in the theory of stability of colloids and films.”J. Colloid and Interface Sci., 103(1), 542–553.
7.
Cleasby, J. L. (1981). “Filtration—back to the basics.”Proc., Am. Water Works Assoc. Seminar: Coagulation and Filtration: Back to the Basics. Am. Water Works Assoc. (AWWA), Denver, Colo.
8.
Cleaver, J. W., and Yates, B.(1973). “Mechanism of detachment of colloidal particles from a flat substrate in a turbulent flow.”J. Colloid and Interface Sci., 44(3), 464–474.
9.
Davidson, J. F., and Harrison, D. (eds.). (1971). Fluidization. Academic Press Inc., New York, N.Y.
10.
Elimelech, M.(1991). “Kinetics of capture of colloidal particles in packed beds under attractive double layer interactions.”J. Colloid and Interface Sci., 146(2), 337–352.
11.
Elimelech, M., and O'Melia, C. R.(1990). “Effect of particle size on collision efficiency in the deposition of Brownian particles with electrostatic energy barriers.”Langmuir, 6(6), 1153–1163.
12.
Fitzpatrick, C. S. B.(1993). “Observations of particle detachment during filter backwashing.”Water Sci. and Technol., London, U.K., 27(10), 213–221.
13.
Ginn, T. A. Jr., Amirtharajah, A., and Karr, P. R.(1992). “Effects of particle detachment in granular-media filtration.”J. AWWA, 84(2), 66–76.
14.
Goldman, A. J., Cox, R. G., and Brenner, H. (1967). “Slow viscous motion of a sphere parallel to a plane wall-coutte flow.”Chemical Engrg., Sci., Oxford, U.K., 22(April), 653–660.
15.
Gregory, J.(1975). “Interaction of unequal double layers at constant charge.”J. Colloid and Interface Sci., 51(1), 44–51.
16.
Hirtzel, C. S., and Rajagopalan, R. (1985). Colloidal phenomena—advanced topics. Noyes Publications, Park Ridge, N.J.
17.
Hubbe, M. A.(1984). “Theory of detachment of colloidal particles from flat surfaces exposed to flow.”Colloids and Surfaces, Amsterdam, The Netherlands, 12(1/2), 151–178.
18.
Hubbe, M. A.(1985). “Detachment of colloidal hydrous oxide spheres from solids exposed to flow. 1: experimental systems.”Colloids and Surfaces, Amsterdam, The Netherlands, 16(3/4), 227–248.
19.
Israelachvili, J. N.(1992). “Adhesion forces between surfaces in liquids and condensable vapours.”Surface Sci. Rep., Amsterdam, The Netherlands, 14(3), 109–159.
20.
Israelachvili, J. N., and Adams, G. E.(1978). “Measurement of forces between two mica surfaces in aqueous electrolyte solutions in the range of 0–100 nm.”J. Chemical Soc., Faraday Trans. I, Cambridge, U.K., 74(4), 975–1001.
21.
Ives, K. J. (1982). “Fundamentals of filtration.”Proc., Symp. on Water Filtration, Eur. Federation of Chemical Engrs., Antwerp, Belgium.
22.
Ives, K. J., and Fitzpatrick, C. S. B.(1989). “Detachment of deposits from sand grains.”Colloids and Surfaces, Amsterdam, The Netherlands, 39(1/3), 239–253.
23.
Kallay, N., Barouch, E., and Matijevic, E.(1987). “Diffusional detachment of colloidal particles from solid/solution interfaces.”Adv. in Colloid and Interface Sci., 27(1/2), 1–42.
24.
Kolakowski, J. E., and Matijevic, E.(1979). “Particle adhesion and removal in model systems.”J. Chemical Soc., Faraday Trans. I, Cambridge, U.K., 75, 65–78.
25.
McDowell-Boyer, L. M.(1992). “Chemical mobilization of micron-sized particles in saturated porous media under steady flow conditions.”Envir. Sci. and Technol., 26(3), 586–593.
26.
Oliphant, J.-L., and Low, P. F.(1982). “The relative partial specific enthalpy of water in montmorillonite-water systems and its relation to the swelling of these systems.”J. Colloid and Interface Sci., 89(2), 366–373.
27.
O'Melia, C. R.(1985). “Particles, pretreatment, and performance in water filtration.”J. Envir. Engrg., ASCE, 111(6), 874–890.
28.
O'Melia, C. R., and Ali, W.(1978). “The role of retained particles in deep filtration.”Progress in Water Technol., London, U.K., 10(5/6), 167–182.
29.
O'Melia, C. R., and Stumm, W.(1967). “Theory of water filtration.”J. AWWA, 59(11), 1393–1412.
30.
O'Neill, M. E.(1968). “A sphere in contact with a plane wall in slow linear shear flow.”Chemical Engrg. Sci., Oxford, U.K., 23(6), 1293–1298.
31.
Pashley, R. M.(1981a). “Hydration forces between mica surfaces in aqueous electrolyte solutions.”J. Colloid and Interface Sci., 80(1), 153–162.
32.
Pashley, R. M. (1981b). “DLVO and hydration forces between mica surfaces in Li +, Na +, K +, and Cs + electrolyte solutions.” J. Colloid and Interface Sci., 83(2), 531–546.
33.
Pashley, R. M., and Israelachvili, J. N. (1984). “DLVO and hydration forces between mica surfaces in Mg 2+, Ca 2+, Sr 2+, and Ba 2+ chloride solutions.”J. Colloid and Interface Sci., 97(2), 446–455.
34.
Peschel, G., Belouschek, P., Muller, M. M., Muller, M. R., and Konig, R.(1982). “The interaction of solid surfaces in aqueous systems.”Colloid and Polymer Sci., Darmstadt, Germany, 260(4), 444–451.
35.
Rabinovich, Ya. I., Derjaguin, B. V., and Churaev, N. V.(1982). “Direct measurements of long-range surface forces in gas and liquid media.”Adv. in Colloid and Interface Sci., 16, 63–78.
36.
Rajagopalan, R., and Chu, R. Q.(1982). “Dynamics of adsorption of particles in packed beds.”J. Colloid and Interface Sci., 86(2), 299–317.
37.
Rajagopalan, R., and Tien, C.(1976). “Trajectory analysis of deep-bed filtration with the sphere-in-cell porous media model.”Am. Inst. of Chemical Engrs. J., 22(3), 523–533.
38.
Raveendran, P. (1993). “Mechanisms of particle detachment during filter backwashing,” PhD dissertation, Georgia Inst. of Technol., Atlanta, Ga.
39.
Raveendran, P., and Amirtharajah, A.(1992). “Mechanisms of particle detachment during filtration and backwashing.”Fluid/Particle Separation J., 5(2), 63–66.
40.
Raveendran, P., and Amirtharajah, A. (1993). “The forces controlling detachment of particles during filter backwashing.”Proc., Joint CSCE-ASCE Nat. Conf. on Envir. Engrg., ASCE, New York, N.Y., 1671–1678.
41.
Ruckenstein, E., and Prieve, D. C.(1976). “Adsorption and desorption of particles and their chromatographic separation.”Am. Inst. of Chemical Engrs. J., 22(2), 276–283.
42.
Ryan, J. N., and Gschwend, P. M.(1994). “Effects of ionic strength and flow rate on colloid release: relating kinetics to interface potential energy.”J. Colloid and Interface Sci., 164(1), 21–34.
43.
Saffman, P. G. (1965). “The lift on a small sphere in slow shear flow.”J. Fluid Mech., Cambridge, U.K., 22(Part 2), 385–400.
44.
Sharma, M. M., Chamoun, H., Sita Rama Sarma, D. S. H., and Schechter, R. S.(1992). “Factors controlling the hydrodynamic detachment of particles from surfaces.”J. Colloid and Interface Sci., 149(1), 121–134.
45.
Shaw, D. J. (1980). Colloid and Surface Chemistry, 3rd Ed., Butterworth-Heinemann Ltd., Stoneham, Mass.
46.
Tabor, D.(1977). “Surface forces and surface interactions.”J. Colloid and Interface Sci., 58(3), 2–13.
47.
Tabor, D. (1982). “Attractive surface forces.”Colloidal Dispersons, J. W. Goodwin, ed., The Royal Soc. of Chem., London, U.K.
48.
Tien, C. (1989). Granular filtration of aerosols and hydrosols, Butterworth Publishers, Stoneham, Mass.
49.
Tien, C., and Payatakes, A. C.(1979). “Advances in deep bed filtration.”Am. Inst. of Chemical Engrs. J., 25(5), 737–759.
50.
Tobiason, J. E. (1987). “Physicochemical aspects of particle deposition in porous media,” PhD dissertation, Johns Hopkins Univ., Baltimore, Md.
51.
Visser, J. (1976). “Adhesion of colloidal particles.”Surface and Colloid Sci., E. Matijevic, ed., John Wiley & Sons, New York, N.Y.
52.
Vold, M. J. (1961). “The effect of adsorption on the van der Waals interaction of spherical particles.”J. Colloid and Interface Sci., 16, 1–12.
Information & Authors
Information
Published In
Copyright
Copyright © 1995 American Society of Civil Engineers.
History
Published online: Dec 1, 1995
Published in print: Dec 1995
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.