Measurement of bubble size distribution in activated sludge bubble column bioreactor

2017 ◽  
Vol 125 ◽  
pp. 212-220 ◽  
Author(s):  
Niloufar Jamshidi ◽  
Navid Mostoufi
2006 ◽  
Vol 122 (1-2) ◽  
pp. 1-10 ◽  
Author(s):  
Subrata Kumar Majumder ◽  
Gautam Kundu ◽  
Dibyendu Mukherjee

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.


2012 ◽  
Vol 51 (16) ◽  
pp. 5705-5714 ◽  
Author(s):  
Mohammad Ramezani ◽  
Navid Mostoufi ◽  
Mohammad Reza Mehrnia

2016 ◽  
Vol 14 (1) ◽  
pp. 213-224 ◽  
Author(s):  
Amir Azimi Yancheshme ◽  
Jamshid Zarkesh ◽  
Davod Rashtchian ◽  
Arezou Anvari

AbstractCFD simulation of cylindrical bubble column including air as dispersed phase and water as continuous phase operating in churn-turbulent flow regime with diameter of 0.49 m, height of 3.6 m and gas superficial velocity of 0.14 m/s have been conducted. All simulations have been carried out in a 2D axisymmetric, unsteady and Euler/Euler framework with the aid of commercial software FLUENT v. 14.5. Simulations were validated by our experimental results through residence time distribution (RTD) data. Effect of bubble size distribution at inlet on column hydrodynamic was investigated and results clearly showed that equilibrium bubble size distribution in most parts of column is independent of bubble size distribution at inlet. In addition, liquid axial velocity and gas hold-up profiles results in column center were approximately the same for cases with different inlet distribution and confirmed similarity of their hydrodynamic.


Author(s):  
Yi-Gang Ding ◽  
Xia Lu ◽  
Fu-Li Deng

A coupled CFD-PBM (population balance mode) model is adopted to investigate complex behavior in a rectangle bubble column. In this work The Euler–Euler (E–E) model was adopted for the liquid phase and gas phase, while accounting for bubble coalescence and breakup a PBM discrete model was employed. The total gas holdup for a range of superficial gas velocities were studied and compared with the literature and modest agreement was found. The simulation result shows that the superficial gas velocity has great effect on bubble size distribution, and a wider bubble size distribution is found at higher superficial gas velocity. This indicates an increasing of the superficial gas velocity increases the bubble coalescence and break-up rate.


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