Qualitative numerical study of simultaneous high-G-intensified gas–solids contact, separation and segregation in a bi-disperse rotating fluidized bed in a vortex chamber

•Bi‐disperse rotating fluidized bed in a static vortex chamber.•Simultaneous high‐G intensified gas–solids contact, separation and segregation.•Coupled discrete particle method – computational fluid dynamics demonstration.•Flexibility with respect to the gas flow rate.•Solids inlet design optimization needed for operation with continuous solids feeding.

Coupled discrete particle method – computational fluid dynamics simulations are carried out to demonstrate the potential of combined high-G-intensified gas–solids contact, gas–solids separation and segregation in a rotating fluidized bed in a static vortex chamber. A case study with two distinct types of particles is focused on. When feeding solids using a standard solids inlet design, a dense and uniform rotating fluidized bed is formed, guaranteeing intense gas–solids contact. The presence of both types of particles near the chimney region reduces, however, the strength of the central vortex and is detrimental for separation and segregation. Optimization of the solids inlet design is required, as illustrated by stopping the solids feeding. High-G separation and segregation of the batch of particles is demonstrated, as the strength of the central vortex is restored. The flexibility with respect to the gas flow rate of the bed density and uniformity and of the gas–solids separation and segregation is demonstrated, a unique feature of vortex chamber generated rotating fluidized beds. With the particles considered in this case study, turbulent dispersion by large eddies in the gas phase is shown to have only a minor impact on the height of the inner bed of small/light particles.

Graphical abstractDemonstration of simultaneous high‐G‐intensified gas–solids contact, gas–solids separation and segregation in a bi‐disperse rotating fluidized bed in a vortex chamber by means of coupled discrete particle method – computational fluid dynamics simulations. Left: Gas entering through the tangential gas inlets slots and strong vortex in the near‐chimney region; Right: Dense and uniform rotating fluidized bed of large/heavy particles against the cylindrical wall and somewhat less dense and faster rotating fluidized bed of small/light particles radially more inward. Black tracer to visualize the flow path of gas injected via one of the slots.Figure optionsDownload full-size imageDownload as PowerPoint slide