A Comparative Study of Gas Holdup, Bubble Size Distribution and Interfacial Area in a Downflow Bubble Column

2005 ◽  
Vol 83 (4) ◽  
pp. 423-428 ◽  
Author(s):  
A. Mandal ◽  
G. Kundu ◽  
D. Mukherjee
Keyword(s):  
Comparative Study ◽  
Size Distribution ◽  
Bubble Size ◽  
Bubble Column ◽  
Interfacial Area ◽  
Gas Holdup ◽  
Bubble Size Distribution

scholarly journals Measurement of Bubble Size, Gas holdup and Interfacial Area in Bubble Columns using Image Processing Techniques

2019 ◽  
Vol 9 (1) ◽  
pp. 4475-4479
Keyword(s):  
Image Processing ◽  
Size Distribution ◽  
Bubble Size ◽  
Bubble Column ◽  
Rectangular Cross Section ◽  
Bubble Diameter ◽  
Water System ◽  
Interfacial Area ◽  
Gas Holdup ◽  
Bubble Size Distribution

Bubble sizes in bubble column affect transfer processes. Therefore, it’s important to calculate bubble size and interfacial area. Bubble size distribution (BSD) in a bubble column of rectangular cross section with dimensions 0.2m x 0.02m was measured using photographic method (400 fps) for air-water system. Gas holdup, Sauter-mean bubble diameter, aspect ratio and specific interfacial area were estimated from BSD. Effect of superficial gas velocity and static bed height on these parameters was investigated. The bubble size distribution exhibited mono-modal distribution showing the presence of non-uniform homogeneous bubbling regime. The frames of video were analysed using image processing steps to obtain major and minor axis of elliptical bubbles. Values of d32, , and ai were estimated from the data. The value of d32 increased with increasing Ug but is independent of Hs. The values of d32 were somewhat higher than the values reported by other investigators. The value of ai increases with increasing Ug and with decreasing Hs. Present values of compared well with the data reported in literature.

Bubble size distribution and gas–liquid interfacial area in a modified downflow bubble column

2006 ◽  
Vol 122 (1-2) ◽  
pp. 1-10 ◽  
Author(s):  
Subrata Kumar Majumder ◽  
Gautam Kundu ◽  
Dibyendu Mukherjee
Keyword(s):  
Size Distribution ◽  
Bubble Size ◽  
Bubble Column ◽  
Interfacial Area ◽  
Bubble Size Distribution

CFD Simulation of Gas Dispersion in a Stirred Tank of Dual Rushton Turbines

2017 ◽  
Vol 15 (4) ◽  
Author(s):  
Xinju Li ◽  
Xiaoping Guan ◽  
Rongtao Zhou ◽  
Ning Yang ◽  
Mingyan Liu
Keyword(s):  
Flow Field ◽  
Size Distribution ◽  
Liquid Flow ◽  
Bubble Size ◽  
Great Influence ◽  
Gas Holdup ◽  
Bubble Size Distribution ◽  
Stirred Tank ◽  
Treatment Methods ◽  
Gas Dispersion

Abstract3D Eulerian-Eulerian model was applied to simulate the gas-liquid two-phase flow in a stirred tank of dual Rushton turbines using computational fluid dynamics (CFD). The effects of two different bubble treatment methods (constant bubble sizevs. population balance model, PBM) and two different coalescence models (Luo modelvs. Zaichik model) on the prediction of liquid flow field, local gas holdup or bubble size distribution were studied. The results indicate that there is less difference between the predictions of liquid flow field and gas holdup using the above models, and the use of PBM did not show any advantage over the constant bubble size model under lower gas holdup. However, bubble treatment methods have great influence on the local gas holdup under larger gas flow rate. All the models could reasonably predict the gas holdup distribution in the tank operated at a low aeration rate except the region far from the shaft. Different coalescence models have great influence on the prediction of bubble size distribution (BSD). Both the Luo model and Zaichik model could qualitatively estimate the BSD, showing the turning points near the impellers along the height, but the quantitative agreement with experiments is not achieved. The former over-predicts the BSD and the latter under-predicts, showing that the existing PBM models need to be further developed to incorporate more physics.

Sign in / Sign up

Export Citation Format

Share Document