Fluidization Properties in Microscale Fluidized Beds
XU Yi-quan GUO Qing-jie SI Chong-dian CAO Chang-qing
College of Chemistry and Chemical Engineering，China University of Petroleum College of Chemical Engineering, Qingdao University of Science and Technology College of Chemical Engineering, Qingdao University of Science and Technology College of Chemical Engineering, Qingdao University of Science and Technology
Abstract：The fluidization characteristics of quartz sand and FCC catalyst particles in 6 microscale fluidized beds with inner diameters of 4.3, 5.5, 10.5, 15.5, 20.5 and 25.5 mm were investigated. The influences of bed diameter (Dt), static bed height (Hs), particles and gas properties on the pressure drop and minimum fluidization velocity (umf) were examined. The results show that the theoretical pressure drops of microscale fluidized beds deviated from the experimental values under different particles and gas properties. The pressure drop correlations for large size fluidized beds failed to compute microscale fluidized beds. umf increased with decreasing Dt. When the ratio of Hs to Dt ranged from 1 to 3, umf was expressed by linear relationship with Hs, while the slope of equation of umf versus Hs decreased with the increase of Dt. Dt/dp and Hs/dp were defined as dimensionless variables, a new equation was developed to predict umf under the present experimental conditions.