Study on fluidization characteristics and separation of fluidized bed flotation using electrical resistance tomography and numerical simulation

Fluidized bed flotation combines the advantages of gravity separation and flotation to achieve effective recovery of coarse minerals. In this study, the fluidization characteristics of pressure, particle distribution, air distribution, and turbulent dissipation rate are investigated by experiment and numerical simulation. Then, the effect of fluidization characteristics on the recovery of quartz beads is analyzed. When the superficial water velocity is below the critical fluidized water velocity, bubble coalescence disturbs the stability of the bed. Meanwhile, the recovery of spherical quartz is unsatisfactory due to the poor fluidity of particles and the nonuniform distribution of air. The recovery of spherical quartz increases sharply with the increase of superficial water velocity after the critical fluidized water velocity. However, the excessive superficial water velocity means too high turbulent dissipation rate, which leads to the increase of detachment probability, resulting in the recovery increasing slowly and finally maintaining between 93 and 94%. [Display omitted] •Fluidized bed flotation was investigated by experiment and numerical simulation.•The critical fluidization velocity of 1 mm quartz beads bed is 0.64 cm/s.•Water velocity significantly influences particles and air distribution.•The recovery of hydrophobic quartz beads is shown as an “ S ” growth curve.•The maximum recovery of hydrophobic quartz beads is 93.95%.