Publication: Partitioning of a wide bubbling fluidized bed with vertical internals to improve local mixing and bed material circulation
Loading...
Identifiers
Publication date
2022-08-01
Defense date
Advisors
Tutors
Journal Title
Journal ISSN
Volume Title
Publisher
Elsevier
Impact
Export
Abstract
Industrial scale fluidized bed reactors are characterized by limited mixing rates, either local or global, especially when using low-pressure drop gas distributors to reduce operational costs. In this work, partitioning of wide beds using vertical internals is proposed as an effective technique to improve local mixing in large reactors, i.e., mixing in specific zones of the bed. The effect of the vertical internals height on local solids mixing within partitions was experimentally evaluated in a pseudo-2D bed by analyzing the velocity and flow structure of the solids and the circulation time within individual partitions. In the presence of internals, global mixing, i.e., mixing between neighboring partitions and across the entire reactor, may be reduced as vertical internals compartmentalize the bed. Thus, the effect of the internals height on global mixing was also quantified while using bed materials with the same properties, but differing in color, in the different partitions, and analyzing the time evolution of the concentration of solids. Furthermore, the effect of internals on bubbles was also evaluated for different internal heights. It was found that internals with a height between the gulf-stream height and the fixed bed height promote the appearance of vortex pair structures in each partition of the wide bed. These structures substantially improve local mixing within each partition, while global mixing between partitions is practically unaffected by the presence of these short internals.
Description
Keywords
Bubbling fluidized bed, Global mixing, Local mixing, Vertical internals
Bibliographic citation
Soria-Verdugo, A., Cano-Pleite, E., Panahi, A., & Ghoniem, A. F. (2022). Partitioning of a wide bubbling fluidized bed with vertical internals to improve local mixing and bed material circulation. Powder Technology, 408, 117771.