Abstract
The bed-to-wall heat transfer coefficients were measured in a circulating fluidized bed of FCC particles (dp = 65 μm). The effects of gas velocity (1.0–4.0 m/s), solid circulation rate (10–50 kg/m2s) and particle suspension density (15–100 kg/m3) on the bed-to-wall heat transfer coefficient have been determined in a circulating fluidized bed (0.1 m-ID x 5.3 rn-high). The heat transfer coefficient strongly depends on particle suspension density, solid circulation rate, and gas velocity. The axial variation of heat transfer coefficients is a strong function of the axial solid holdup profile in the riser. The obtained heat transfer coefficient in terms of Nusselt number has been correlated with the pertinent dimensionless groups
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Arena, U., Cammarato, A. and Piston, L., “High Velocity Fluidization Behavior of Solids in a Laboratory Scale Circulating Fluidized Bed”, CFB Technology., Basu, P. eds, Pergamon Press, New York, 119 (1986).
Bai, D. R., Jin, Y., Yu, Z. Q. and Zhu, J. X., “The Axial Distribution of the Cross-Sectionally Averaged Voidage in Fast Fluidized Beds”,Powder Technol.,71, 51 (1992).
Baskakov, A. P., Maskaev, V. K., Ivanov, I. V. and Usoltsev, A. G., “Experimental Study of Heat Transfer from the Wall of a Channel to a CFB”,J. Eng. Physics,59, 1570 (1991).
Basu, P. and Fraser, S. A., “Circulating Fluidized Bed Boiler: Design and Operation”, Butterworth-Heinemann, Boston (1991).
Basu, P. and Nag, P. K., “An Investigation into Heat Transfer in Circulating Fluidized Beds”,Int. J. Heat Mass Transfer,30, 2399 (1987).
Chen, C. C. and Chen, C. L., “Experimental Study of Bed-to-Wall Heat Transfer in a Circulating Fluidized Bed”,Chem. Eng. Sci.,47, 1017 (1992).
Dou, S., “Heat Transfer Characteristics in Circulating Fluidized Beds”, Ph.D. Dissertation, Lehigh University, Bethlehem, USA (1991).
Glicksman, L. R., “Circulating Fluidized Bed Heat Transfer”, CFB Technology II, Basu, P. and Large, J. F., eds., Pergamon Press, New York, 13 (1988).
Grace, J. R., “Heat Transfer in Circulating Fluidized Beds”, CFB Technology, Basu, P. eds., Pergamon Press, New York, 63 (1986).
Han, G. Y., “Experimental Study of Radiative and Particle Convective Heat Transfer in Fast Fluidized Beds”, Ph.D. Dissertation, Lehigh University, Bethlehem, U.S.A. (1992).
Hartge, E. V., Li, Y. and Werther, J., “Analysis of the Local Structure of Two-Phase Flow in a Fast Fluidized Bed”, CFB Technology, Basu, P. eds., Pergamon Press, Canada, 153 (1986).
Holman, J. P., “Heat Transfer”, McGraw-Hill, New York (1986).
Kobro, H. and Brereton, C. M. H., “Control and Fuel Flexibility of Circulating Fluidized Bed”, CFB Technology, Basu, P. eds., Pergamon Press, New York, 263 (1986).
Li, Y. and Kwauk, M., “The Dynamics of Fast Fluidization”, Fluidization, Grace and Masten eds., Plenum Press, New York, 537 (1980).
Nag, P. K. and Moral, M. N. A., “Effect of Probe Size Heat Transfer at the Wall in a CFB”,Int. J. Energy Research,14, 965 (1990).
Namkung, W., Cho, Y. J. and Kim, S. D., “Axial Solid Holdup Distribution in a Circulating Fluidized Bed”,Hwahak Konghak,32, 241 (1994).
Rhodes, M. J. and Geldart, D., “The Hydrodynamics of Re-Circulating Fluidized Beds”, CFB Technology, Basu, P. eds., Pergamon Press, New York, 194 (1986).
Wu, R. L., Lim, C. J., Chaouki, J. and Grace, J. R., “Heat Transfer from a Circulating Fluidized Bed to Membrane Waterwall Surfaces”,AIChE J.,33, 1888 (1987).
Wu, R. L., Grace, J. R., Lim, C. J. and Brereton, C. M. H., Suspension-to-Surface Heat Transfer in a Circulating Fluidized Bed Combustor”,AIChE J.,35, 1685 (1989a).
Wu, R. L., Lim, C. J. and Grace, J. R., “The Measurement of Instantaneous Local Heat Transfer Coefficients in a CFB”,Can. J. Chem. Eng.,67,3011 (1989b).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Cho, Y.J., Kim, S.D. & Han, G.Y. Bed-to-wall heat transfer characteristics in a circulating fluidized bed. Korean J. Chem. Eng. 13, 627–632 (1996). https://doi.org/10.1007/BF02706030
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02706030