The influence of axial dispersion on carbon dioxide absorption tower performance
Article first published online: 17 JUN 2004
Copyright © 1966 American Institute of Chemical Engineers
Volume 12, Issue 3, pages 541–548, May 1966
How to Cite
Brittan, M. I. and Woodburn, E. T. (1966), The influence of axial dispersion on carbon dioxide absorption tower performance. AIChE J., 12: 541–548. doi: 10.1002/aic.690120327
- Issue published online: 17 JUN 2004
- Article first published online: 17 JUN 2004
- Manuscript Accepted: 12 JAN 1966
- Manuscript Revised: 5 JAN 1966
- Manuscript Received: 8 JUN 1965
Carbon dioxide was absorbed from mixtures with nitrogen by countercurrent contact with water in an experimental packed tower. Radial and axial gas concentration profiles were determined from measurements made within the packing. Substantial gas phase channeling was observed. Characterizing the gas flow regime by both piston flow and axial diffusion models yielded mass transfer data and computed axial gas concentration profiles. Differences between the mass transfer results for the two models allowed the influence of axial dispersion to be assessed. Comparison of the piston flow and axially dispersed profiles with the experimental profiles enabled conclusions to be drawn regarding the applicability of the axial diffusion model and the accuracy of available dispersion parameter values.
The axial diffusion model appears to be a satisfactory representation of the process. The dispersion coefficients used were found to be too high, which emphasizes shortcomings in the transient response experiments yielding dispersion coefficients. The influence of dispersion on the performance was found to be only moderately adverse. The effect increases with increasing liquid rate, decreasing gas rate, and decreasing packing height. It is improbable that the effect is large enough to account for the difference between industrial scale performance and that predicted from available mass transfer correlations.