A study of cocurrent downflow of nonfoaming gas-liquid systems in a packed bed. 2. Pressure drop: search for a correlation

Abstract

Pressure drop is an important parameter in the design of gas/liquid cocurrent downflow packed bed reactors. It is needed in calculating the energy required for pumping and compression, as well as in sizing related equipment.It also affects the operating pressure and gas-phase reactant partial pressure. Pressure drop has been used by several workers to correlate gas-liquid and liquid-solid mass transfer. In this study past work in the literature is reviewed and the most significant correlations are examined against measurements from the present work on six nonfoaming gas-liquid systems with a 5.1 cm i.d. glass column packed with spherical glass beads of 1.9 mm diameter to a height of 85 cm, with liquid and gas superficial mass velocities ranging from 3 to 30 kg/m2 s and 0.0005 to 1.0 kg/m2 s, respectively. A new correlation of the Lockhart-Martinelli type is proposed which agrees well with two similar correlations in the literature.

Pulse properties in gas–liquid flow through randomly packed beds under microgravity conditions

“…According to our picture, this should translate into the following effects on the liquid-continuous pattern (bubbly flow) in the packed bed: (1) a stabilizing effect of liquid viscosity, (2) a non-significant effect of surface tension (as interstitial gas velocities in the packed bed are in the lower range of gas velocities studied by Laborie et al), and (3) a destabilizing effect of gas inertia. These are exactly the trends observed by Tosun (1984) and reproduced in his Figs. 2-4, respectively.…”

Mathematical modeling of pulsing flow in large trickle beds

“…As the flow rates were increased, the pulses became wider and flatter. The pressure drops observed in this column were considerably lower than the predictions by literature correlations (Sato et al, 1973;Midoux et al, 1976;Tosun, 1984) that were obtained from experiments in small-diameter columns, indicating that large differences exist between the nature of pulsing flow in small-diameter columns and columns of large cross section. Average liquid holdups measured in the column of rectangular cross section over a wide range of conditions in the pulsing regime agreed well with the predictions of Sat0 et al and of Midoux et al, indicating that the liquid holdup is approximately independent of column crosssectional area.…”

Flue gas desulphurization based on limestone-gypsum with a novel wet-type PCF device

“…8, p increases proportionally with superficial gas velocity increasing. Their relationship can be described with [24][25][26]. When the superficial gas velocity reaches 3.5 m/s (5.97 m/s in inner cylinder), the pressure drop of the PCF device is only 1200 Pa around; while that of other absorbers is high up to 1500 Pa and even higher.…”