Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

1 Publication

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

Rabha, S.; Schubert, M.; Wagner, M.; Lucas, D.; Hampel, U.

Gas hold-up and bubble size distribution in a slurry bubble column (SBC) were measured using the advanced non-invasive 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 solids 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 solids 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.

Keywords: Slurry bubble column; gas hold-up; bubble size distribution; ultrafast electron beam X-ray tomography

Publ.-Id: 17555