Mixing in trickle flow through packed beds

Trickle bed hydrodynamics and flow regime transition at elevated temperature for a Newtonian and a non-Newtonian liquid

“…The correlation of Liles and Geankoplis (1960) shows that D ax increases with temperature for both systems. The correlation of Michell and Furzer (1972) shows no significant effect of temperature on D ax . The correlation of Piché et al (2002) shows also no systematic effect of temperature on D ax , in agreement with experimental data.…”

“…It seems that even if this correlation has been developed using a broad D ax database, it will necessitate parameters recalibration for moderate-to-high pressures and non-ambient temperatures for Newtonian and non-Newtonian liquids. The average absolute mean errors for the air-water system were equal to 49%, 46% and 59%, respectively for the correlations of Michell and Furzer (1972), Liles and Geankoplis (1960) and Piché et al (2002). For the air-water system, the effect of superficial liquid velocity on the axial dispersion coefficient is more pronounced than for the air-0.25% CMC system.…”

“…This may be explained by a lowering in backmixing due to a decrease in liquid holdup with temperature. Experimental D ax data is plotted along with the values calculated from the correlation of Michell and Furzer (1972), Liles and Geankoplis (1960) and Piché et al (2002) ( Table 3). The correlation of Liles and Geankoplis (1960) shows that D ax increases with temperature for both systems.…”

Trickle‐bed reactors

“…Some fifteen or so other studies have been reported of liquid phase axial dispersion but generally for countercurrent air-water systems, almost invariably with ring or saddle packing, and sometimes for flow conditions outside the range of interest in trickle bed reactors. A summary listing is given by Michell and Furzer (1972) who present a recommended correlation based on a considerable amount of their own work. This involves a Reynolds number ReL' based on the interslitial rather than the superficial velocity and therefore must be combined with an expression for the dynamic holdup Hf to relate superficial and interstitial velocities.…”

An improved algorithm for solving the mass balance equations in multistage separation processes

“…(2) and all dispersive effects are attributed to the axial dispersion coefficient, E, . Michell and Furzer (1972) showed statistically that the model could not account for the dispersive effects adequately. The same conclusion was drawn by Hoogendoorn and Lips (1965), Bennett and Goodridge (1970), as well as Van Swaaij et al (1969) who pointed out that the Axially Dispersed Plug Flow Model gives too early a breakthrough and insufficient tailing.…”