Segregation of binary particles in gas-solid fluidized bed

Abstract

Particle segregation and mixing behavior play a crucial role in industrial processes. This study investigates the saturated jetsam fraction, which indicates the maximum capacity of flotsam to entrain jetsam, in an initially separated binary fluidized bed with particle size differences. According to the value of saturated jetsam fraction, three distinct regimes—segregation, mixing, and an intermediate regime—are identified. Moreover, intriguing relationships between the saturated jetsam fraction and superficial gas velocity are observed, exhibiting monotonic trends in both the segregation and mixing regimes, while a unique volcano-shaped curve in the intermediate regime. Additionally, a comprehensive entrainment model based on two-fluid model elucidates the observed phenomena, emphasizing the significance of mixing behavior in fluidized layer on the saturated jetsam fraction. This work offers potential insights for evaluating segregation in industrial applications.

Graphical abstract

Keywords

fluidized bed / segregation / binary / bubbles / entrainment

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