Segregation of equal-sized particles of different densities in a vertically vibrated fluidized bed Articles uri icon

publication date

  • July 2017

start page

  • 101

end page

  • 110

volume

  • 316

international standard serial number (ISSN)

  • 0032-5910

electronic international standard serial number (EISSN)

  • 1873-328X

abstract

  • The present work experimentally studies the influence of vibration and gas velocity on the density-induced segregation of particles in a pseudo-2D vibrated fluidized bed. One half of the particles of the bed are ballotini spheres of density 2500 kg/m(3) and the other half are heavier ceramic particles of density 4100 kg/m(3) or 6000 kg/m(3). Digital Image Analysis is used to characterize the rate and extent of particle mixing with time for different gas velocities, vibration amplitudes and frequencies. The results of the experiments indicate that the vibration strength and the gas velocity have an important effect on both the evolution and the final extent of density-induced particle segregation. It was observed that by introducing vertical vibration to a bed that is fluidized close to minimum fluidization conditions the rate of segregation and the final segregation index of a mixture of light and dense particles is enhanced. However, for vibration strengths greater than a critical value around 3-4, the degree of segregation decreases due to a more vigorous three dimensional mixing of particles in the bed. (C) 2017 Elsevier B.V. All rights reserved.

keywords

  • fluidized bed; pseudo-2d; vibration; segregation; isolated bubbles