ISSN:
0001-1541
Keywords:
Chemistry
;
Chemical Engineering
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Equations in terms of a pulse Reynolds number and dimensionless pulse velocity are presented for mass transfer coefficients in pulsed flow in a packed bed. Mass transfer from the wall and from the particles is considered. The development, applicable up to a particle Reynolds number of 40, is based upon a previous study of pulsed laminar flow in an empty tube.The experimental measurements consisted of rates of dissolution of β-naphthol from the wall and from the particles within the bed. From these data time-average mass transfer coefficients kp were computed. The improvement in kp increased with frequency and decreased with average flow rate, although the increase was always less than in an empty tube at equivalent conditions.Steady flow measurements indicated that the coefficient for mass transfer from the tube wall was influenced by the degree of settling of the bed. This effect could be related to the change in porosity accompanying the settling process. A new empirical correlation is proposed to account for the effect of porosity changes.
Additional Material:
9 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/aic.690100535
