Prediction of minimum fluidization velocity of gas–solid fluidized beds by pressure fluctuation measurements — Analysis of the standard deviation methodology

✍ Scribed by C.A.S. Felipe; S.C.S. Rocha

• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 528 KB
• Volume: 174
• Category: Article
• ISSN: 0032-5910
• DOI: 10.1016/j.powtec.2007.01.015

✦ Synopsis

We analyze here an experimental method for the evaluation of U mf in gas fluidized beds, based on pressure fluctuation measurements in which U mf is determined by the relationship between the standard deviation of pressure measurements and fluid velocity [M. Puncochar, J. Drahos, J. Cermak, K. Selucky, Evaluation of minimum fluidizing velocity in gas fluidized bed from pressure fluctuations, Chem. Eng. Commun. 35 (1985) 81-87]. This was tested in four different particles: Sand, Microcrystalline Cellulose, FCC and Alumina using two circular plexiglass columns with internal diameters of 0.11 m and 0.14 m as the experimental apparatus. Validation of the method was made by comparing our U mf results with those obtained by the fluid-dynamic curve. The experimental data revealed that: (1) the valid range of fluid velocity in the method employed by us is broader than those observed by other authors; (2) the method is suitable for both Geldart A and B solids. Influence of probe location and type of pressure measurement (either absolute or differential) were also analyzed and discussed.