{"title":"Correlation to Predict the Effect of Particle Type on Axial Voidage Profile in Circulating Fluidized Beds","authors":"M. S. Khurram, S. A. Memon, S. Khan","volume":119,"journal":"International Journal of Chemical and Molecular Engineering","pagesStart":1371,"pagesEnd":1375,"ISSN":"1307-6892","URL":"https:\/\/publications.waset.org\/pdf\/10005741","abstract":"
Bed voidage behavior among different flow regimes for Geldart A, B, and D particles (fluid catalytic cracking catalyst (FCC), particle A and glass beads) of diameter range 57-872 μm, apparent density 1470-3092 kg\/m3<\/sup>, and bulk density range 890-1773 kg\/m3<\/sup> were investigated in a gas-solid circulating fluidized bed of 0.1 m-i.d. and 2.56 m-height of plexi-glass. Effects of variables (gas velocity, particle properties, and static bed height) were analyzed on bed voidage. The axial voidage profile showed a typical trend along the riser: a dense bed at the lower part followed by a transition in the splash zone and a lean phase in the freeboard. Bed expansion and dense bed voidage increased with an increase of gas velocity as usual. From experimental results, a generalized model relationship based on inverse fluidization number for dense bed voidage from bubbling to fast fluidization regimes was presented.<\/p>\r\n","references":"[1]\tD. Escudero, and T. 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