aDept. of M.E., Anjuman College of Engg. and Technology, Nagpur, India
bChemical Engg. Dept., Laxminarayan Institute of Techology, Nagpur, India e-mail: akashlangde@gmail.com
Achieving fine particles to fluidize are very difficult with conventional methods, due to strong interparticle attraction. The difficulty of putting these powders in suspension in the fluidizing gas is related to the cohesive structure and, in particular, to the physical forces between the primary particles. Large inerparticle forces lead to bed cracking, slugging and channeling, and cause the powder not to fluidize consistently. In this study the fluidization behavior of Fly ash of micronic diameter belonging to the group C of Geldart's classification has been investigated. The basic aim of this research work was to improve the quality of fluidization of Fly ash (dp=18μm) by applying external source in terms of acoustic field. In addition, effect of acoustic field and variation of frequency on minimum fluidization velocity (Umf) and on minimum bubbling velocity has been found out. It was observed that Umf decreases in presence of acoustic field with homogenous fluidization. The best effect observed at 145dB and 120Hz. Fluidization under acoustic field allows to partly overcome the adhesion forces between powders. The fluidization behavior has been improved for the highest sound intensity.
Minimum fluidization velocity, Acoustic field, frequency, fine powder, group C
