Fluidization of fine powder assisted by vertical vibration in fluidized bed reactor

Abstract

This study examined the fluidization phenomenon using vertical vibration for fine powder in a mechanical vertical vibration for fluidized bed reactor. The fine powder used belongs to the Geldart group C with a mean powder size of 2.25 µm. It was verified that channeling and agglomeration phenomena appeared with a fluidization method without vibration of fine powders belonging to the group C. To keep fluidization phenomenon of the agglomerating fine powder superior, a smooth fluidization condition was made by giving vertical vibration function and removing cohesion between particles. To verify the smooth fluidization condition of the fine powder, changes in the bed height to diameter (H/D) ratio of the fluidized bed reactor, pressure drop due to changes of vibration frequency with superficial gas velocity, minimum fluidization velocity, and changing characteristics of bed expansion ratio were investigated experimentally. This study examined pressure drops from H/D variable of values 1 and 2, minimum fluidization velocity, and bed expansion ratios at 0 to 60 Hz of vibration frequency. There is a trend that as vibration frequency increases, the pressure drop is stabilized, minimum fluidization velocity decreases, and the bed expansion ratio increases.