Experimental study on the fluidization behaviors of the superfine particles

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Vol. 262; pp. 579 - 587
• Main Authors: Liu, Huanpeng, Zhang, Linyao, Chen, Taiping, Wang, Shaowei, Han, Zongjie, Wu, Shaohua
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.02.2015
• Subjects: Agglomerate diameter; Agglomerate voidage; Cohesive force; Fluidization; Superfine particle; Fluidization; Cohesive force; Agglomerate voidage; Agglomerate diameter; Superfine particle
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2014.09.124

•Micro-particles can also be fluidized in the APF regime like nano-particles.•The agglomerate size of micro-particles has the multi-scale characteristic.•The distribution of agglomerate diameter is in subject to the Gaussian distribution.•There exists the minimum agglomerate size under any given fluidization condition.•Agglomerate voidage is large and has great effect on the gas-agglomerate flow. In this study, the fluidization behaviors of the superfine particles with the mean diameter of 5.181μm were studied. The bed collapse experiment was conducted to study the fluidization quality and regime. The minimum fluidization velocity based on the agglomerate was determined. The agglomerate size distribution characteristic was studied by the 2D Particle Image Velocimetry (PIV). The agglomerate voidage was measured and discussed. The results showed that the micro-particles can also be fluidized in the agglomerate particulate fluidization regime like the nano-particles. The minimum fluidization velocity based on the agglomerate is 3.4cm/s and much larger than that based on the primary particle. The agglomerate size has the multi-scale characteristic. The distribution of agglomerate diameter is in subject to the Gaussian distribution. And there exists the minimum agglomerate diameter under the effect of van der Waals cohesive force. The agglomerates in different sizes and shapes may have the similar particle arrangement structure. The measured averaged agglomerate voidage is 0.966. It may have an important effect on the interaction between the gas and agglomerate phases.