Gas holdup in two- and three-phase downflow bubble columns

Gas holdup in bubble column with surface‐active agents: A theoretical model

“…The gas holdup was found to increase as follows: methanol < ethanol < n-propanol < n-butanol. An opposite trend was observed by Shah et al (1983) in a downflow system. It should be noted that both these authors found no effect of alcohol concentration on the gas holdup, and that the homogeneous bubble flow regime prevailed for n-butanol, n-propanol, and ethanol solutions.…”

Investigation of Downflow Bubble Columns: Experiments and Modeling

“…Since the natural tendency of the bubbles is to rise, the interplay between their forced downward flow and their natural tendency to move up causes a net enhancement in the average gas phase residence time. In turn, this result in higher gas holdup and mass transfer coefficient values even at lower gas velocities compared to conventional upflow bubble column (Shah et al, 1983;Ohkawa et al, 1985;Lu et al, 1994).…”

Characterization of gas-liquid parameters in a down-flow jet loop bubble column

“…In a sparger type system, the gas sparger is fixed at the top of the column. Liquid with high velocity is forced through the column and, as it moves, it shears the gas from the sparger in the form of bubbles (Shah et al, 1983;Kulkarni and Shah, 1984). The concept of plunging jet in a downflow column comes from the studies of gas entrainment and dispersion by a liquid jet impinging into a pool of liquid (Van de Sande and Smith, 1973;McKeogh and Ervine, 1981).…”