Absorption and Chemisorption of Small Levitated Single Bubbles in Aqueous Solutions

Processes

Alexander Tollkötter¹ 

[1] TU Dortmund University, BCI, Equipment Design, Emil-Figge-Straße 68, D-44227 Dortmund, Germany; E-Mail

关键词: mass transfer;    levitation;    bubble;    drag force coefficient;    Sherwood number;   

DOI  :  10.3390/pr2010200

来源: mdpi

【 摘 要 】

The absorption and chemisorption of small bubbles with N₂ or CO₂ were investigated experimentally in aqueous and alkaline solutions. Different bubble sizes were studied ranging from 0.1 to 2.5 mm in alkaline concentrations of 0.1 mM to 1 M NaOH. The experiments were conducted in a device consisting of a converging microchannel with a down flowing liquid. Levitation positions of single bubbles were optically characterized. A correlation was developed for the drag force coefficient, C_D, including wall effects based on the force equilibrium. A linear decrease of bubble diameters was identified with and without chemical reaction, which is referred to as a rigid bubble surface area. Measured Sherwood numbers agree well with the literature values for the investigated Reynolds number range.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.