Fluidized-Bed Reactors

A fluidized bed is a bed of solid particles that are supported by the drag of upward-flowing gas or liquid. The particles are in continuous motion, and the suspension behaves like a dense fluid, which can be drained from the bed through pipes and valves. If the bed is tilted, the top surface remains horizontal, and large objects will either sink or float on the bed, depending on the relative densities. A naturally occurring example of fluidization is quicksand, where fine sand particles are suspended by upflowing water. Most industrial applications of fluidization involve solids and gases, which is the focus of this chapter.