Bubble size and radial gas hold-up distributions in a slurry bubble column using ultrafast electron beam X-ray tomography

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Swapna Rabha - , Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Author)
  • Markus Schubert - , Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Author)
  • Michael Wagner - , Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Author)
  • Dirk Lucas - , Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Author)
  • Uwe Hampel - , Chair of Imaging Techniques in Energy and Process Engineering (with HZDR), Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Author)

Abstract

Gas hold-up and bubble size distribution in a slurry bubble column (SBC) were measured using the advanced noninvasive ultrafast electron beam X-ray tomography technique. Experiments have been performed in a cylindrical column (DT = 0.07 m) with air and water as the gas and liquid phase and spherical glass particles (dP = 100 μm) as solids. The effects of solid concentration (0 ≤ Cs ≤ 0.36) and superficial gas velocity (0.02 ≤ UG ≤ 0.05 m/s) on the flow structure, radial gas hold-up profile and approximate bubble size distribution at different column heights in a SBC were studied. Bubble coalescence regime was observed with addition of solid particles; however, at higher solid concentrations, larger bubble slugs were found to break-up. The approximate bubble size distribution and radial gas hold-up was found to be dependent on UG and Cs. The average bubble diameter calculated from the approximate bubble size distribution was increasing with increase of UG. The average gas hold-up was calculated as a function of UG and agrees satisfactorily with previously published findings. The average gas hold-up was also predicted as a function of Cs and agrees well for low Cs and disagrees for high Cs with findings of previous literature.

Details

Original languageEnglish
Pages (from-to)1709-1722
Number of pages14
JournalAIChE Journal
Volume59
Issue number5
Publication statusPublished - May 2013
Peer-reviewedYes

Keywords

Keywords

  • Bubble size distribution, Gas hold-up, Slurry bubble column, Ultrafast electron beam X-ray tomography