Abstract��The fluidization characteristics of ultrafine powder TiO2 with an average diameter of 387 nm were investigated in a semi-cylindrical internal circulating fluidized-bed of 120 mm in diameter under three kinds of fluidization condition, introducing fluidizing gas individually, jet gas individually or both gases at the same time. The results indicated that fluidizing gas can promote the circulation of powder and eliminate dead zone in annulus; high-speed jet can effectively break the agglomerates and significantly reduce their size as the fluidizing gas and jet gas were introduced at the same time, so that the stable circulation of ultrafine powder between annulus and draft tube can be achieved and the small agglomerates can be fluidized steadily in annulus. Furthermore, the influence of jet gas velocity on the size of agglomerates was tested in this experiment as well. It was found that the size of the agglomerates becomes smaller and the size distribution becomes narrower with the increased jet gas velocity. The average diameters of the agglomerates were 194, 158, 147, and 135 μm under the condition of the jet gas velocity were 60, 90, 120, and 150 m/s, respectively.
Zhang Guojie,Pi Liqiang,Yang Xingcan et al. Fluidization Behavior of Ultrafine Powders in an Internal Circulating Fluidized-Bed[J]. ��ѧ��Ӧ�����빤��, 2015, 31(3): 262-265.
