Gas Holdup and Liquid-Phase Dispersion in Packed Bubble Columns
Article Sidebar
Main Article Content
Abstract
The gas holdup and liquid phase axial dispersion coefficient are measured in two semi batch packed bubble columns, 10 and 15 cm diameter for an air–water system, at atmospheric conditions. The experiments were carried out using a transient method (the tracer response method). The dispersion coefficient was obtained by adjusting the experimental profiles of tracer concentration with the predictions of the model. Experiment results of packed bubble column, shows a considerable reduction of the back mixing. The investigations have been carried out using RTD measurements and the back mixing is usually characterized by the axial dispersion coefficient obtained from the one-dimensional axial dispersion model. Also, a decrease in superficial gas velocity reduces the liquid back mixing. It is observed that the liquid circulation comprises an upward flow in the column core and a downward flow along the wall. It also seen that the transition from the bubbly flow to the pulsation flow regime occurred at 5-6 cm/s superficial gas velocity.
Metrics
Article Details
This work is licensed under a Creative Commons Attribution 4.0 International License.
THIS IS AN OPEN ACCESS ARTICLE UNDER THE CC BY LICENSE http://creativecommons.org/licenses/by/4.0/
Plaudit
References
Shah, Y.T., Stiegel, G.J., Sharma, M.M., “Backmixing in Gas-Liquid Reactors”, AIChE J. 24 (1978) 369-400. DOI: https://doi.org/10.1002/aic.690240302
Stiegel, G.J. and Shah, Y.T., “Backmixing and Liquid Holdup in a Gas Liquid Co-Current Up flow Packed Column”, Ind. Eng. Chem. Proc. Des. Dev. 16 (1977) 37. DOI: https://doi.org/10.1021/i260061a006
Abraham, M. and Sawant, S.B., “Hydrodynamic and Mass Transfer Characteristics of Packed Bubble Columns”, Chem. J. 43 (1990) 95-105. DOI: https://doi.org/10.1016/0300-9467(90)80011-Z
Niranjan, K. and Pangarkar, V.G., “Gas Holdup and Mixing Characteristics of Packed Bubble Columns”, Chem. J. 29 (1984) 101-111. DOI: https://doi.org/10.1016/0300-9467(84)85031-5
Turpin, J.L. and Huntington, R.L., “Prediction of Pressure Drop for Two-Phase, Two Component Co-current flow in Packed Beds”, AIChE J. 13 (1967) 1196-1202. DOI: https://doi.org/10.1002/aic.690130630
Krishna, R., Urseanu, M.I., van Baten, J.M., Ellenberger J., “Liquid Phase Dispersion in Bubble Columns Operating in the Churn-Turbulent Flow Regime”, Chem. Eng. J., 78, 43–51, (2000). DOI: https://doi.org/10.1016/S1385-8947(99)00167-9
Rubio, F. C. , miron, A. S. , Garcia, M. C. , Camacho, F. G. , Grima, E. M. , Chisti, Y. “Mixing in Bubble Columns: A New Approach for Characterizing Dispersion Coefficients“, Chem. Eng. Sci., 59, 4369-4376, (2004). DOI: https://doi.org/10.1016/j.ces.2004.06.037
Siemes, W. and Weiss, W., 1957, Flfissigkeitsdurchmischung in engen Blasens~ulen. Chem.-lngr.-Tech. 29, 727-732, (1957). (Sited in Ohki et al., 1970) DOI: https://doi.org/10.1002/cite.330291105
Ohki, Y. and Inoue H., “Longitudinal Mixing of The Liquid Phase in Bubble Columns”, Chem. Eng. Sci., 25, 1-16, (1970). DOI: https://doi.org/10.1016/0009-2509(70)85016-3
Hikita, H. and Kikukawa, H.,”Liquid-Phase Mixing in Bubble Columns: Effect of Liquid Properties”, Chem. Eng. J., 8, 191-197, (1974). DOI: https://doi.org/10.1016/0300-9467(74)85024-0
Hofmann, H., “Der derzeitige stand bei der vorausberechnung der verweilzeitverteilung in technischen reaktoren”, Chem. Eng. Sci. 14 (1961) 193-208. DOI: https://doi.org/10.1016/0009-2509(61)85075-6
Gelder, K.B., and Westerterp, K.R., “Residence Time Distribution and Hold-up in a Co-current Upflow Packed Bed Reactor at Elevated Pressure”, Chem. Eng. & Technology 13 (1990) 27-40. DOI: https://doi.org/10.1002/ceat.270130106
Campos, J.B.L.M. and Guedes de Carvalho, J.R.F.A., “A new Experimental Technique to Study Backmixing in Packed Bubble Columns”, Chem. Eng. Sci. 47 (1992) 4063-4067. DOI: https://doi.org/10.1016/0009-2509(92)85157-7
Carleton, A.J., Flain, R.J., Rennie, J., Valentin, F.H.H., “Some Properties of a Packed Bubble Column”, Chem. Sci. 22 (1967) 1839-1845. DOI: https://doi.org/10.1016/0009-2509(67)80214-8
Deckwer, W. D. “Bubble column reactors”. New York: Wiley (1992).
Sahay, B.N., and Sharma, M.M., “Absorption in Packed Bubble Columns”, Chem. Sci. 28 (1973) 2245-2255. DOI: https://doi.org/10.1016/0009-2509(73)85013-4
Yang, Y. B., Devanathan, N. and Dudukovik, M. P., “Liquid Backmixing in Bubble Columns”, Chem. Sci., 47, 2859, (1992). DOI: https://doi.org/10.1016/0009-2509(92)87142-D
Miyauchi, T., Furusaki, S., Morooka, S. and Akida, Y., “Transport Phenomena and Reaction in Fluidized Catalyst Beds”, Advances in Chemical Engineering, Vol. 11, p. 275-448 (1981). (Sited in Degaleesan et al., 1998) DOI: https://doi.org/10.1016/S0065-2377(08)60028-9
VanBaten, J. M., and Krishna, R., “Scale Up Studies on Partitioned Bubble Column Reactors with the Aid of CFD Simulations“, Catalysis Today, 79-80, 219-227, (2003). DOI: https://doi.org/10.1016/S0920-5861(03)00008-7
Degaleesan, S., and Dudukovik, M. P., “Liquid Backmixing in Bubble Columns and the Axial Dispersion Coefficient“, AIChE J., 44, 11, 2369-2378, (1998). DOI: https://doi.org/10.1002/aic.690441105
Wilkinson, P. M. , Spek, A. P. , and van Dierendonck, L. L., “Design Parameters Estimation for Scale-Up of High-Pressure Bubble Columns”, AIChE J., Vol. 38, 544-554, (1992). (Sited in Krishna, et al., 1996). DOI: https://doi.org/10.1002/aic.690380408
Kantak, M. V., Shetty, S. A. and Kelkar, B. G., “Liquid Phase Backmixing in Bubble Column Reactors – A New Correlation”, Chem. Eng. Commun., 127, 23-34, (1994). (Sited in http://ct=cr4.chem .uva.nl/partition.). DOI: https://doi.org/10.1080/00986449408936223
Towell, G. D. and Ackerman, G. H., “Axial Mixing of Liquids and Gas in Large Bubble Reactor”, Proceedings of 2nd International Symposium Chem. React. , Amsterdam. The Netherlands, B3.1-B3.13, (1972). (Sited in http://ct=cr4.chem.uva.nl /partition.)
Schugerl, K., Todt, J., Lucke, J., and Renken, A., “Gas Holdup and Longitudinal Dispersion in Different Types of Multiphase Reactors and their Possible Application for Microbial Processes”, Chem. Sci., 32, 369-375, (1977). DOI: https://doi.org/10.1016/0009-2509(77)85003-3
Baird, M. H. I. and Rice, R. G.,”Axial Dispersion in Large Unbaffled Columns”, Chem. J., 9, 171-174, (1975). DOI: https://doi.org/10.1016/0300-9467(75)80010-4