Effects of spiral internal, solid feeding rate, fluidized gas velocity, particle size and bed height on the particle residence time distribution were investigated in a cold bubbling fluidized bed using the tracer technique. The results showed that the dimensionless variance of particle residence time reduced from 0.558 without spiral internal to 0.085 with a spiral internal, indicating that the spiral internal helped restrain the back mixing of particles and made the flow approach the plug flow. When the solid feeding rate was doubled, the residence time of particles decreased by approximately 50% and the flow was closer to plug flow. As the increased bed height caused severe back mixing, both average residence time and dimensionless variance increased and the solid flow tended to be complete stirred flow. The average residence time of particles extended with the increasing of fluidized gas velocity. Particle size had a little effect on the residence time distribution under present experimental conditions.
Yiwei DU Xin WU Daojie LIU Junhui LI
. Residence Time Distribution of Particles in Fluidized Bed with Spiral Internal[J]. The Chinese Journal of Process Engineering, 2018
, 18(3)
: 484
-490
.
DOI: 10.12034/j.issn.1009-606X.217329
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