Fluidization techniques

Fluidization involves passing a fluid phase (very often a gas) through a bed of particles, supported by a grid, to bring them into suspension. The term fluidization comes from the fact that the gas/solid suspension is brought into a fluid-like state. For example, if the fluidized bed were tilted, the surface of the suspension would remain horizontal and would not follow the movement of the container. It is also possible to plunge an object into the fluid bed without any particular resistance from the suspension, as would be the case with a fluid. This is because particle/particle friction forces are generally negligible (with the exception of cohesive powders), even though the particles are relatively free to move.