Structuring chaotic fluidized beds

Abstract Three new ways are proposed to “structure” bubbling gas–solid fluidized beds, i.e. to bring order into their chaotic hydrodynamics. Just like for fixed bed reactors, the rational structuring of fluidized beds, a novel concept, is interesting from the point of view of process intensification, to facilitate scale-up and control, and to improve performance. Applying an AC electric field, reduces the average bubble size by manipulating interparticle forces. Introducing part of the gas via a fractal injector, immersed into the bed, homogenizes the bed contents, considerably improves gas–solid contact, and simplifies scale-up. Oscillating the gas flow transforms chaotic bubble motion into remarkably regularly ordered patterns of rising bubbles.

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