FBG 200 Fluid Bed Granulator

In brief, the fluidized bed processor (FBP) introduces an additional coating function compared to the fluidized bed granulator (FBG), enabling simultaneous completion of mixing, drying, granulation, and coating operations. The core difference between the two lies in the nozzle positioning: the fluidized bed processor (FBP) employs a bottom spray, while the fluidized bed granulator (FBG) uses a top spray. Both methods achieve granulation through bridging effects between materials.

However, the top-spray FBG exhibits significantly higher granulation efficiency than the bottom-spray FBP. In the FBG bed, materials are fully suspended, tumbling, and colliding without fixed trajectories. The nozzles spray downward, directing droplets directly into the fluidized bed layer, where they instantly collide and coalesce with abundant suspended materials, achieving a droplet utilization rate of ≥80%. Simultaneously, hot gas uniformly permeates the entire bed, allowing droplet coalescence to be dried concurrently, thereby substantially enhancing granulation efficiency.

The fluidized bed granulator is not entirely incapable of achieving coating, but it imposes significant limitations on coating materials—mist droplets are prone to premature volatilization by the hot gas stream, resulting in thin and uneven coating films. This makes it suitable only for scenarios where customers require an extremely thin coating thickness. However, mainstream industries such as pharmaceuticals typically require thick coatings. Therefore, the fluidized bed coating equipment commonly used in practical applications is mostly fluidized bed processors.