Gas hold-up and axial mixing in the fluid phase of bubble columns

✍ Scribed by T. Reith; S. Renken; B.A. Israël

• Publisher: Elsevier Science
• Year: 1968
• Tongue: English
• Weight: 722 KB
• Volume: 23
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(68)89007-4

✦ Synopsis

Gas hold-up and liquid phase axial dispersion coefficient have been measured in water filled bubble columns of 5.08, 14.0 and 29sOcm dia. as a function of the superficial gas velocity. From the gas hold-up measurements the following relationship between the relative velocity between gas and liquid, u,., the superficial gas velocity, u,,.,,, and the rise velocity of a single bubble, u.. can be established: 0, = 2 v,,s,+ 0,. The axial dispersion in the 14 and 29 cm column can be characterized by a nearly constant P&let number based on the column diameter, D, and the relative gas velocity: P~&=3~010~3 I for superficial gas velocities between 10 and 45 cm/set.

One series of experiments with ionic solutions (140 g NaCl per litre of water) was performed. Although higher gas hold-ups and lower relative gas velocities were measured, the axial dispersion coefficient could again be characterized by in the same range of superficial gas velocities.

In the 5.08 cm column slug flow was observed.