Abstract
Digital image analysis (DIA) was used to achieve some information related to aspect ratio of the bubbles, bed expansion fluctuations and the emulsion area at different gas velocities and different bed heights. All experiments were done in a pseudo-2D gas-solid fluidized bed. Variations of the bubble fraction at different gas velocities and different bed heights were investigated. It was found that when the excess gas velocity increases, the dimensionless bed height increases linearly with slope of about 0.4 for LLDPE particles. To validate the analysis, the bubble diameter achieved by DIA results in this work was compared with the bubble diameter correlation presented by Shen et al. Bubble aspect ratio in different heights of the bed was extracted through image analysis, and it was observed that the bubble aspect ratio first increases with the bed height and near the freeboard becomes flattened. Results of the experiments show that the emulsion phase becomes more expanded at higher excess gas velocities. As demonstrated by the analysis results, by increasing the bed height, bubble fraction parameter is decreased.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
D. Kunii and O. Levenspiel, Fluidization Engineering, Elsevier (2013).
J. Nieuwland, M. Veenendaal, J. Kuipers and W. Van Swaaij, ChEnS, 51, 4087 (1996).
O. Olaofe, K. Buist, N. Deen, M. van der Hoef and J. Kuipers, Powder Technol., 244, 61 (2013).
A. Busciglio, G. Vella, G. Micale and L. Rizzuti, Chem. Eng. J., 140, 398 (2008).
S. Mori and C. Wen, AIChE J., 21, 109 (1975).
P. Rowe and B. Partridge, Chem. Eng. Res. Des., 75, S116 (1997).
J. Kuipers, W. Prins and W. Van Swaaij, ChEnS, 46, 2881 (1991).
K. Lim, P. Agarwal and B. O’neill, Powder Technol., 60, 159 (1990).
A. S. Hull, Z. Chen, J.W. Fritz and P. K. Agarwal, Powder Technol., 103, 230 (1999).
G.R. Caicedo, J. J. P. Marqués, M. G. Ruiz and J. G. Soler, Chem. Eng. Process., 42, 9 (2003).
M. Goldschmidt, J. Link, S. Mellema and J. Kuipers, Powder Technol., 138, 135 (2003).
L. Shen, F. Johnsson and B. Leckner, ChEnS, 59, 2607 (2004).
J.A. Laverman, I. Roghair, M. v. S. Annaland and H. Kuipers, CJChE, 86, 523 (2008).
A. Busciglio, G. Vella, G. Micale and L. Rizzuti, Chem. Eng. J., 148, 145 (2009).
T.W. Asegehegn, M. Schreiber and H. J. Krautz, Powder Technol., 210, 248 (2011).
S. Movahedirad, A. Molaei Dehkordi, M. Banaei, N. Deen, M. van Sint Annaland and J. Kuipers, Ind. Eng. Chem. Res., 51, 6571 (2012).
S. Movahedirad, M. Ghafari and A. Molaei Dehkordi, Chem. Eng. Technol., 37, 103 (2014).
J. Guardiola, G. Ramos and R. Elvira, ChEnS, 95, 33 (2013).
D. Geldart, Powder Technol., 7, 285 (1973).
J. Link, L. Cuypers, N. Deen and J. Kuipers, ChEnS, 60, 3425 (2005).
C. A. Schneider, W. S. Rasband and K.W. Eliceiri, Nat. Methods, 9, 671 (2012).
T. Ridler and S. Calvard, ITSMC, 8, 630 (1978).
S. Movahedirad, M. Ghafari and A. M. Dehkordi, Chem. Eng. Technol., 35, 929 (2012).
S. Movahedirad, A. Molaei Dehkordi, N. G. Deen, M. van Sint Annaland and J. Kuipers, AIChE J., 58, 3306 (2012).
Author information
Authors and Affiliations
Corresponding author
Electronic supplementary material
Rights and permissions
About this article
Cite this article
Salehi-Asl, M., Azhgan, S. & Movahedirad, S. Some general aspects of a gas-solid fluidized bed using digital image analysis. Korean J. Chem. Eng. 35, 613–620 (2018). https://doi.org/10.1007/s11814-017-0291-y
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11814-017-0291-y