ATTRITION AND CHANGES IN PARTICLE-SIZE DISTRIBUTION OF LIME SORBENTS IN A CIRCULATING FLUIDIZED-BED ABSORBER

Citation
Jl. Cook et al., ATTRITION AND CHANGES IN PARTICLE-SIZE DISTRIBUTION OF LIME SORBENTS IN A CIRCULATING FLUIDIZED-BED ABSORBER, Powder technology, 89(1), 1996, pp. 1-8
Citations number
20
Categorie Soggetti
Engineering, Chemical
Journal title
ISSN journal
00325910
Volume
89
Issue
1
Year of publication
1996
Pages
1 - 8
Database
ISI
SICI code
0032-5910(1996)89:1<1:AACIPD>2.0.ZU;2-S
Abstract
The attrition data of calcium oxide pellets in a circulating fluidized bed absorber (CFBA) are presented with a modified second-order attrit ion model incorporating an asymptotic minimum bed weight and an excess gas velocity from the minimum fluidization. Two sizes (903 and 1764 m u m) of calcium oxide pellets are fluidized with several superficial g as velocities. The experimental attrition rate constants obtained from the attrition model are used to fit a modified Arrhenius equation, wi th a pseudo activation energy term proportional to the excess fluidizi ng energy. The model with the measured rate constants for single-parti cle size is used to predict the changes in size distribution in a bed with a mixture of various particle sizes. The present method may be ap plicable for batch and continuous operations of fluidized beds in whic h size reduction predominantly results from attrition and elutriation frequently seen in a fast fluidized bed and in a circulating fluidized bed.