Results 111 to 120 of about 12,269 (159)

A general correlation to predict axial dispersion coefficients in aerated channel reactors

Water Research, 2008
Tracer studies have been widely applied to characterize the flow behavior in activated sludge reactors. The channel reactor with bottom aerators is one of the widespread designs in large wastewater treatment plants. Its flow behavior is well modeled either as a plug flow reactor with axial dispersion or as the perfect mixing cells in series.
Le Moullec, Y., Potier, O., Gentric, C., Leclerc, J.-P.   +3 more
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Axial Dispersion Coefficients in Laminar Flows of Water-Distribution Systems

Journal of Hydraulic Engineering, 2011
Because longitudinal dispersion is becoming increasingly germane to the problem of accurately determining water quality, water-resource managers and engineers seeking to represent solute transport in drinking-water systems must be able to compute relevant dispersion coefficients.
Pedro Romero-Gomez, Christopher Y. Choi
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Correlation of axial mixing of solids in fluidized beds by a dispersion coefficient

Powder Technology, 1984
Abstract Axial mixing of solids in a 19.3 cm diameter bed was investigated using a tracer technique. Bed material and tracer consisted of ion-exchange resin particles of 0.846 mm and 0.645 mm diameter, respectively. Tracer concentration profiles were measured. The results were expressed as axial dispersion coefficients.
A. Esin, M. Altun
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Measurement of transverse and axial apparent dispersion coefficients in packed beds

AIChE Journal, 1996
AbstractThe axial and transverse apparent dispersion coefficients of three solvents in two packed chromatographic columns were determined by pulsed‐field‐gradient nuclear‐magnetic resonance in a range of mobile phase velocity. The column beds were packed with 5‐ μm particles of porous C18 silica or 30‐μm particles of silica.
Ulrich Tallarek, Klaus Albert, Ernst Bayer, Georges Guiochon   +3 more
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Behavior of macromolecules in dilute solutions: II—On the axial dispersion coefficient

The Canadian Journal of Chemical Engineering, 1975
AbstractUsing pulse‐input technique, axial dispersion coefficients were determined for polystyrene in tetrahydrofuran, in toluene and in a toluene/methanol mixture flowing in a long capillary tube under conditions such that the Reynolds number was less than 500. Low polydispersity polystyrene materials with nominal molecular weights ranging from 900 to
H. R. Chen, L. P. Blanchard
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Axial dispersion coefficients in packed beds at low reynolds numbers

The Canadian Journal of Chemical Engineering, 1969
AbstractPeclet numbers describing axial dispersion in gas flow through packed beds of spheres were obtained using a two measurement point, pulse technique in a test section four inches inside diameter and 5.14 feet high. Three packing sizes were investigated, corresponding to tube to particle diameter ratios of 6.4, 17, and 66In the experiments the ...
Jack C. Urban, A. Gomezplata
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The simultaneous determination of axial dispersion and mass transfer coefficients

Chemical Engineering Science, 1967
Abstract A method is illustrated for the simultaneous determination of axial dispersion and mass transfer parameters for some continuous flow process operations. The procedure involves the matching of computed and experimental axial concentration profiles.
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Axial Dispersion Coefficients for Laminar Flows in Water Distribution Systems

World Environmental and Water Resources Congress 2009, 2009
A dispersive transport component has recently been incorporated into the constituent transport equation used for modeling water quality in pressurized distribution systems. Among the various issues that arose from this major development, dispersion coefficients (E) relevant to water distribution systems still remain unknown.
P. Romero-Gomez, Z. Li, C. Y. Choi, S. G. Buchberger   +3 more
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A simplified model for prediction of time-dependent axial dispersion coefficient

Chemical Engineering Science, 1991
Abstract A simple model is proposed for prediction of the axial dispersion coefficient as a function of time. The model contains only a single parameter called the decay time, which is the time required for the mean concentration to approach 1 e of its initial value. The asymptotic value of this coefficient for large times approaches the value
Mohammad Soltanieh, Sasan Sadraei
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A unified correlation for predicting liquid axial dispersion coefficient in bubble columns

Chemical Engineering Science, 2001
Abstract Experimental measurements of gas holdup and liquid axial dispersion coefficients have been carried out in two bubble columns (column I; D c =15 cm and column II; D c =20 cm ), operating with co-current upflow of gas and liquid. In addition, measurement of bubble size was investigated.
S Moustiri, G Hebrard, S.S Thakre, M Roustan   +3 more
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