Modelling and Measurement of Bubble Formation and Growth in Electroflotation Processes

• Authors: Shahjahan K. A. Sarkar , Piotr M. Machniewski , Geoffrey M. Evans
• Languages of publication: EN

Abstracts

EN

Electroflotation is used in the water treatment industry for the recovery of suspended particles. In this study the bubble formation and release of hydrogen bubbles generated electrolytically from a platinum cathode was investigated. Previously, it was found that both the growth rate and detachment diameter increased with increasing wire diameter. Conversely, current density had little effect on the released bubble size. It was also found that the detached bubbles rapidly increased in volume as they rose through the liquid as a result of decreasing hydrostatic pressure and high levels of dissolved hydrogen gas in the surrounding liquid. The experimental system was computationally modelled using a Lagrangian-Eulerian Discrete Particle approach. It was revealed that desorption of gaseous solutes from the electrolyte solution, other than hydrogen, may have a significant impact on the diameter variation of the formed bubbles. The simulation confirmed that liquid circulation, either forced or induced by the rising bubble plume, influences both the hydrogen supersaturation (concentration) in the neighbourhood of the electrode and the size of the resulting bubbles.

Keywords

EN

electroflotation; bubble diameter; detachment; mass transfer; CFD modelling

• Publisher: De Gruyter Open
• Journal: Chemical and Process Engineering
• Year: 2013
• Volume: 34
• Issue: 3
• Pages: 327-336

Dates

published

1 - 09 - 2013

online

08 - 10 - 2013

Contributors

author

Shahjahan K. A. Sarkar

• School of Engineering, The University of Newcastle, Callaghan, NSW, 2308 Australia

author

Piotr M. Machniewski

• Warsaw University of Technology, Faculty of Chemical and Process Engineering, ul. Waryńskiego 1, 00-645 Warsaw, Poland

author

Geoffrey M. Evans

• School of Engineering, The University of Newcastle, Callaghan, NSW, 2308 Australia

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Identifiers

DOI

10.2478/cpe-2013-0026