Mass Dispersion in Liquid Flow through Packed Beds

Abstract

Liquid flow experiments, in which a tracer was introduced as a point source, were performed in a thin two-dimensional packed bed. These simple experiments demonstrated the essential features of hydrodynamic dispersion in packed beds. The standard Fickian-type model and the wave model were compared with respect to their ability to describe the tracer propagation. The wave model does so adequately, in contrast to the erroneous predictions by the Fickian-type model. Arguments are provided to show that the application of hyperbolic-type equations improves the description of dispersion in packed-bed reactors.

A critical comparison between the wave model and the standard dispersion model

“…Comprehensive experimental studies of Schouten, Borman, and Westerterp (1994) showed systematic deviations between the theoretical results and experimental data for a wall-cooled packed-bed reactor, when transport and kinetics parameters are measured independently. Furthermore, di usion-type models also contradict the experiment of Hiby (1963) and Benneker, Kronberg, Lansbergen, and Westerterp (2002).…”

“…This means that the model predicts propagation of the tracer upstream. However, the observed proÿles can be perfectly explained by the wave model (Benneker et al, 2002).…”

Sorption of copper by a highly mineralized peat in batch and packed‐bed systems

“…The axial dispersion coefficient could be estimated by tracing techniques in the packed bed. 19,20 The main objective of this work was to evaluate the sorption characteristics of a locally available highly mineralized peat for the removal of copper in batch and continuous flow conditions. It was intended to demonstrate the effect of pH on the metal uptake capacity and the influence of the contact type on the equilibrium isotherm.…”