Elsevier

Powder Technology

Volume 87, Issue 2, May 1996, Pages 105-111
Powder Technology

Characterization of gas fluidization regimes using pressure fluctuations

https://doi.org/10.1016/0032-5910(95)03072-7Get rights and content

Abstract

Flow regimes varying from bubbling fluidization to pneumatic transport were characterized by analyzing the differential pressure fluctuations. Two kinds of particles, typifying those from group A and group B, were employed in the experiments. It is found that, under all the operating conditions and at various axial positions, the standard deviation of the differential pressure fluctuations almost coincides, if the solids holdup is the same. For the two particles employed, the dimensionless standard deviations normalized by the maximum standard deviation at Uc showed a unique relationship with the solids holdup, giving a favorable characteristic that allows the determination of the boundaries between the flow regimes of gas-solids fluidization. Based on the experimental results, we find approximate values of: ϵsb > ϵs > 0.35, for bubbling fluidization; 0.15 < ϵs < 0.35, for turbulent fluidization; 0.05 < ϵs < 0.15 for fast fluidization; and ϵs < 0.05 for pneumatic transport.

References (38)

  • M. Schnitzlein et al.

    Chem. Eng. Sci.

    (1988)
  • H.T. Bi et al.

    Chem. Eng. J.

    (1995)
  • J. Drahoš et al.

    Powder Technol.

    (1988)
  • H. Takeuchi et al.

    Powder Technol.

    (1986)
  • T. Hirama et al.

    Powder Technol.

    (1992)
  • L.W. Bolton et al.
  • C.M.H. Brereton et al.

    Chem. Eng. Sci.

    (1993)
  • W. Zhang et al.

    Chem. Eng. Sci.

    (1991)
  • B. Zou et al.

    Powder Technol.

    (1994)
  • S.-P. Chen et al.

    Powder Technol.

    (1993)
  • J. Yerushalmi et al.

    Powder Technol.

    (1979)
  • S. Morooka et al.

    Powder Technol.

    (1980)
  • D. Kunii et al.

    Powder Technol.

    (1990)
  • S. Mori et al.
  • A. Lancia et al.

    Powder Technol.

    (1988)
  • M. Tsukada et al.

    Int. J. Multiphase Flow

    (1993)
  • J. Yerushalmi et al.
  • J.R. Grace

    Can. J. Chem. Eng.

    (1986)
  • H.T. Bi
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    Present address: Department of Chemical Engineering, The University of British Columbia, 2216 Main Mall, Vancouver, BC, V6T IZ4, Canada.

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