On mass transfer from a Newtonian fluid to a swarm of adsorbing spheroidal particles for high Peclet numbers

Journal Article · Mon Nov 01 04:00:00 EST 1993 · Journal of Colloid and Interface Science; (United States)

DOI:https://doi.org/10.1006/jcis.1993.1438· OSTI ID:5836483

Coutelieris, F A; Burganos, V N; Payatakes, A C ^[1]

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1. Univ. of Patras (Greece). Dept. of Chemical Engineering

Mass transfer from a moving fluid to a swarm of adsorbing stationary particles is encountered in a large number of industrial processes (chemical reactors, filters, flooding processes, etc.). The problem of mass transfer from a Newtonian fluid stream to a swarm of adsorbing stationary solid spheroidal particles under creeping flow conditions is considered. The spheroid-in-cell'' model is used for the representation of the swarm and the axis of symmetry is assumed parallel to the approaching uniform stream. An analytical solution to the convective diffusion equation for high Peclet number is obtained using Levich's method. Simple analytical expressions are derived for the dimensionless concentration, the local Sherwood number, and the thickness of the diffusion layer in terms of the Peclet number, the porosity of the swarm, and the position on a meridian plane. It is found that for prolate spheroids-in-cell the diffusion film thickness is minimal at the stagnation point as in the case of spheres-in-cell. However, in the case of oblate spheroids-in-cell the diffusion layer thickness becomes minimal at positions between the stagnation point and the equator. Calculated values of the overall mass transfer coefficient indicate that the adsorption rate is higher for oblate spheroids-in-cell than for spheres-in-cell and prolate spheroids-in-cell, assuming either the same volume, or the same surface area. The mass transfer coefficient increases with decreasing porosity of the swarm for all geometries studied.

• OSTI ID: 5836483
• Journal Information: Journal of Colloid and Interface Science; (United States), Journal Name: Journal of Colloid and Interface Science; (United States) Vol. 161:1; ISSN 0021-9797; ISSN JCISA5
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ADSORBENTS
ADSORPTION
DIFFUSION
DIMENSIONS
FLOW MODELS
FLOW RATE
FLUIDS
LAYERS
LIQUIDS
MASS TRANSFER
MATHEMATICAL MODELS
POROSITY
SHAPE
SORPTION
STAGNATION
THICKNESS