1. Fluidized-bed granulation

Fluidized-bed particle granulation is a process that brings together three phases: solid, liquid and gas. It's a complex process, involving simultaneous and competitive stages such as mixing, pulverizing, wetting, drying, etc. The industrial boom in this technique is due in particular to the advantages offered by fluidization and, in particular, the very intense transfer of material and heat, and the perfect mixing of the solid in the contactor.

The principle of the operation is relatively simple: the solid particles are suspended in the bed by a stream of hot air, and a solution containing the binder is injected into the bed (figure 1 ). The heat required to evaporate the solvent is supplied by the fluidizing air. This technique has the advantage of performing several...