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Solids mixing in a fluidized bed riser

โœ Scribed by Chaoyu Yan; Yiping Fan; Chunxi Lu; Yongmin Zhang; Yansheng Liu; Rui Cao; Jinsen Gao; Chunming Xu


Publisher
Elsevier Science
Year
2009
Tongue
English
Weight
402 KB
Volume
193
Category
Article
ISSN
0032-5910

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โœฆ Synopsis


The solids mixing in a riser with a height of 10 m and 0.186 m inner diameter was investigated by using pneumatic phosphor tracer technique. Considering the shielding effect of the bed material on the light emitted from the phosphor tracer particle, a modified method for the phosphor tracer measurement is proposed. And then the curves of particle residence time distribution were obtained. The experimental results show that the particle diffusion mechanism can be explained by the dispersions of dispersed particles and particle clusters in the axial direction, and as well the core-annulus nonuniform distribution of the solids fraction in the radial direction of the riser. Moreover, based on the experimental results, a two-dimensional dispersion model was established to predict the solids axial and radial diffusion. Furthermore, the effects of superficial gas velocity and solids circulating flux on the axial and radial Peclet number of the particles were discussed; two empirical correlation formulas about the axial and the radial Peclet numbers were given; the calculated values agree well with the experimental results.


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