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The transient settling of stable and flocculated dispersions

Published online by Cambridge University Press:  26 April 2006

FranÇois M. Auzerais ,
R. Jackson ,
W. B. Russel  and
W. F. Murphy
FranÇois M. Auzerais
Affiliation:
Department of Chemical Engineering, Princeton University, Princeton, NJ 08544–5263, USA
R. Jackson
Affiliation:
Department of Chemical Engineering, Princeton University, Princeton, NJ 08544–5263, USA
W. B. Russel
Affiliation:
Department of Chemical Engineering, Princeton University, Princeton, NJ 08544–5263, USA
W. F. Murphy
Affiliation:
Schlumberger-Doll Research, Old Quarry Road, Ridgefield, CT 06877–4108, USA
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Abstract

An experimental investigation of the sedimentation of monodisperse colloidal silica spheres with grafted octadecyl chains with three different interaction potentials is presented. Small particles (0.27 μm) behaved as hard spheres in cyclohexane, but larger ones (0.60 and 0.94 μm) are weakly flocculated by van der Waals attractions. The smallest particles (0.08 μm) in hexadecane are strongly flocculated by attractions between the octadecyl layers. A medical computer tomography (CT) scanner provided an accurate and absolute density measurement without disrupting the process. For the hard spheres and the weakly flocculated systems, the kinetics of sedimentation for the dispersed phase could readily be predicted utilizing the flux curve. For flocculated networks, we found a power-law relationship between compressive yield stresses and solids fractions comparable with other experimental systems.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 221 , December 1990 , pp. 613 - 639
Copyright
© 1990 Cambridge University Press

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References

Auzerais, F. M., Jackson, R. & Russel, W. B., 1988 The resolution of shocks and the effects of compressible sediments in transient settling. J. Fluid Mech. 195, 437–462.Google Scholar
Barclay, L., Harrington, A. & Ottewill, R. H., 1972 The measurement of forces between particles in disperse systems. Kolloid-Z.-u.Z. Polymere 250, 655–666.Google Scholar
Batchelor, G. K.: 1972 Sedimentation in a dilute dispersion of spheres. J. Fluid Mech. 52, 245–268.Google Scholar
Batchelor, G. K.: 1976 Brownian diffusion of particles with hydrodynamic interactions. J. Fluid Mech. 74, 1–29.Google Scholar
Been, K. & Sills, G. C., 1981 Self weight consolidation of soft soils: an experimental and theoretical study. Geotechnique 31, 519–535.Google Scholar
Bogush, G. H. & Zukoski, C. F., 1986 The colloidal chemistry of growing silica spheres. Proc. Microstructures, Berkeley. Ca., July.Google Scholar
Buscall, R.: 1981 The elastic properties of structured dispersions: a simple centrifuge method of examination. Colloids Surf. 5, 269–283.Google Scholar
Buscall, R.: 1990 The sedimentation of concentrated colloidal suspensions. Colloids Surf. 43, 33–53.Google Scholar
Buscall, R., Goodwin, J. W., Ottewill, R. H. & Tadros, Th. F., 1982 The settling of particles through newtonian and non-newtonian media. J. Colloid Interface Sci. 85, 78–86.Google Scholar
Buscall, R., Mills, P. D. A., Goodwin, J. W. & Lawson, D. W., 1988 Scaling behaviour of the rheology of aggregate networks formed from colloidal particles. J. Chem. Soc. Faraday Trans. I 84, 4249–4260.Google Scholar
Buscall, R. & White, L. R., 1987 The consolidation of concentrated suspensions. J. Chem. Soc. Faraday Trans. I 83, 873–891.Google Scholar
Carslaw, H. S. & Jaeger, J. C., 1959 Conduction of Heat in Solids, p. 206. Oxford University Press.
Davis, K. E. & Russel, W. B., 1989 An asymptotic description of transient settling and ultrafiltration of colloidal dispersions. Phys. Fluids A 1, 82–100.Google Scholar
Davis, K. E., Russel, W. B. & Glantschnig, W. J., 1989 Disorder-to-order transition in settling suspensions of colloidal silica: X-ray measurements. Science 245, 507–510.Google Scholar
Derjaguin, B. V. & Landau, L. D., 1941 Theory of the stability of strongly charged lyophobic sols and the adhesion of strongly charged particles in solutions of electrolytes. Acta Physicochim. URSS 14, 633–662.Google Scholar
Fitch, B.: 1986 In Solid/Liquid separation scale-up, clarification and thickening, Chap. 4. (ed. D. B. Purhcas & R. J. Wakeman) London: Uplands.
Gaudin, A. M. & Fuerstenau, M. C., 1958 Eng. Mining J. 159, 110.
Hounsfield, G. N.: 1972 A method of and apparatus for examination of a body by radiation such as X- or Gamma-radiation. British patent No 1,283,915, London.
Howe, A. M. & Robins, M. M., 1990 Determination of gravitational separation in dispersions from concentration profiles. Colloids Surf. 43, 83–94.Google Scholar
Jansen, J. W., De Kruif, C. C. & Vrij, A., 1986a Attractions in sterically stabilized silica dispersions. II. Experiments on phase separation induced by temperature variation. J. Colloid Interface Sci. 114, 481–491.Google Scholar
Jansen, J. W., De Kruif, C. G. & Vrij, A., 1986b Attractions in sterically stabilized silica dispersions. IV. Sedimentation. J. Colloid, Interface Sci. 114, 481–491.Google Scholar
Kops-Werkhoven, M. M. & Fijnaut, H. M. 1981 Dynamic light scattering and sedimentation experiments on silica dispersions at finite concentration. J. Chem. Phys. 74, 1618–1625.Google Scholar
De Kruif, C. G., Jansen, J. W. & Vrif, A., 1987 A sterically stabilized silica colloid as a model supramolecular fluid. In Physics of Complex and Supramolecular Fluids, pp. 315–347. Wiley Interscience.
De Kruif, C. G., Rouw, P. W., Jansen, J. W. & Vrij, A., 1985 Hard sphere properties and crystalline packing of lyophilic silica colloids. J. Phys. Colloq. C3 46, 295–308.Google Scholar
Kynch, G. J.: 1952 A theory of sedimentation. Trans. Faraday Soc. 48, 166–176.Google Scholar
Landman, K. A., Buscall, R. & White, L. R., 1988 The continuous flow gravity thickener: steady state behaviour. AIChE J. 34, 239–252.Google Scholar
Mahanty, J. & Ninham, B. W., 1976 Dispersion Forces. Academic.
Matijevic, E.: 1976 Preparation and characterization of monodisperse metal hydrous oxide sols. Prog. Colloid Polymer Sci. 61, 24–35.Google Scholar
Michaels, A. A. & Bolger, J. C., 1962 Settling rates and sediment volumes of flocculated kaolin suspensions. Ind. Engng Chem. Fundam. 1, 24–33.Google Scholar
Ondeka, J. G., Henry, J. D. & Verhoff, F. H., 1978 Indirect measurement of sedimentation rates at high temperature and pressure by X-ray photography, Ind. Engng Chem. Fundam. 3, 217–221.Google Scholar
Ottewill, R. H.: 1980 Direct measurements of particle-particle interactions. Prog. Colloid Polymer Sci. 67, 71–83.Google Scholar
Payne, J. T. & Mccullough, E. C., 1976 Basic principles of computer-assisted tomography. Appl. Radiol. March-April, pp. 230–39.Google Scholar
Rhee, H. K., Aris, R. & Amundson, N. R., 1976 First order Partial Differential Equations. Vol I, Theory and Application of Single Equations, pp. 350–360. Prentice-Hall.
Roscoe, K. H., Arthur, J. R. F. & James, R. G. 1963 Strains in soils by X-ray method. Civil Engng Public Works Rev. July, 873–1012.Google Scholar
Russel, W. B., Schowalter, W. R. & Saville, D. A., 1989 Colloidal Dispersions. Cambridge University Press.
Shannon, P. T., Dehaas, R. D., Stroupe, E. P. & Tory, E. M., 1964 Batch and continuous thickening. Ind. Engng Chem. Fundam. 3, 250–260.Google Scholar
Shannon, P. T., Stroupe, E. P. & Tory, E. M., 1963 Ind. Engng Chem. Fundam. 2, 203.
Stöber, W., Fink, A. & Bohn, E., 1968 Controlled growth of monodisperse silica spheres in the micron size range. J. Colloid Interface Sci. 26, 62–69.Google Scholar
Tan, C. G., Bowen, B. D. & Epstein, N., 1967 Production of monodispersed colloidal silica spheres: effect of temperature. J. Colloid Interface Sci. 118, 290–293.Google Scholar
Thiele, E.: 1963 Equation of state for hard spheres. J. Chem. Phys. 39, 474–477.Google Scholar
Tiller, F. M.: 1981 Revision of Kynch sedimentation theory. AIChE J. 27, 823–829.Google Scholar
Tiller, F. M. & Yeh, C. S., 1990 Relative liquid removal in filtration and expression. Filtr. Sep. 27, 123–135.Google Scholar
Tory, E. M.: 1961 Batch and continuous thickening of slurries. Ph.D. thesis. Purdue University.
Van Helden, A. K., Jansen, J. W. & Vrij, A., 1981 Preparation and characterization of spherical monodisperse silica dispersions in nonaqueous solvents. J. Colloid Interface Sci. 81, 354–368.Google Scholar
Verwey, E. J. W. & Overbeek, J. Th. 1948 Theory of the Stability of Lyophobic Colloids. Elsevier.
Wellington, S. L. & Vinegar, H. J., 1987 X-ray computerized tomography. J. Petrol. Techn. August, 885–898.Google Scholar
Woodcock, L. V.: 1981 Glass transition in the hard-sphere model and Kauzmann's paradox. Ann. NY Acad. Sci. 37, 274–298.Google Scholar