Gas Holdup and Liquid-Phase Dispersion in Packed Bubble Columns

• Main Author: Burhan S. Abdulrazzaq
• Format: Article
• Language: English
• Published: Tikrit University 2013-04-01
• Series: Tikrit Journal of Engineering Sciences
• Subjects: Packed Bubble columns, Gas holdup, Liquid dispersion, Liquid circulation
• Online Access: http://www.tj-es.com/ojs/index.php/tjes/article/view/124

<p>The gas holdup and liquid phase axial dispersion coefficient are measured in two semi batch packed bubble columns, 10 and 15 cm diameter for an air–water system, at atmospheric conditions. The experiments were carried out using a transient method (the tracer response method). The dispersion coefficient was obtained by adjusting the experimental profiles of tracer concentration with the predictions of the model. Experiment results of packed bubble column, shows a considerable reduction of the backmixing. The investigations have been carried out using RTD measurements and the backmixing is usually characterized by the axial dispersion coefficient obtained from the one-dimensional axial dispersion model. Also, a decrease in superficial gas velocity reduces the liquid backmixing.  It is observed that the liquid circulation comprises an upward flow in the column core and a downward flow along the wall. It also seen that the transition from the bubbly flow to the pulsation flow regime occurred at 5-6 cm/s superficial gas velocity.</p>