Bubble column reactors
The gas holdup distribution is a key parameter for the design of efficiently operating bubble column reactors. Measurements on bubble columns in our laboratories as well as at our industry partner Evonik Industries delivered new knowledge concerning axial and radial gas holdup distributions and flow structures for different industrial inlet geometries, liquids and operating pressures.
With its high sampling frequency the gamma-ray CT system could be successfully applied for the validation of a new method to measure the gas phase dispersion in industrial-scale bubble columns. Therefore, the volume flow rate of the gas phase is slightly modulated and synchronised with the projection data acquisition of the gamma-ray system. Experiments have been carried out with gas/water and gas/glycol-water mixtures. The axial dispersion model was adopted to determine the gas phase dispersion coefficient from phase shift and amplitude damping of the gas holdup frequency response.
Funding
Supported by BMBF (01.11.2011 - 01.11.2014). Mark: 01RC1102-x
References
- A. Doess et al.
Non-invasive determination of gas phase dispersion coefficients in bubble columns using periodic gas flow modulation
Chemical Engineering Science 171, 256-270, 2017. [doi: 10.1016/j.ces.2017.05.019] - DE102014118649
Anordnung und Verfahren zur Dispersionsmessung sowie Mehrphasenapparat mit einer solchen Anordnung - A. Bieberle et al.
Gamma-ray computed tomography for imaging of multiphase flows
Chemie Ingenieur Technik Vol. 85 / 7, pp. 1002-1011, 2013. [doi:10.1002/cite.201200250] - R. Rollbusch et al.
Experimental investigation of the influence of column scale, gas density and liquid properties on gas holdup in bubble columns
International Journal of Multiphase Flow 75, pp. 88-106, 2015. [doi:10.1016/j.ijmultiphaseflow.2015.05.009]