Granulation with fluid bed equipment

Fluid bed systems have been utilized in the pharmaceutical industry for numerous years. The addition of an aqueous or alcoholic granulation medium agglomerates the dry powder particles. This fluid contains a volatile solvent that can be removed through drying.

Top-spray fluidized bed solutions have been the predominant choice for a long time. However, top-spray granulators are gradually being replaced with tangential spray nozzle systems as their advantages become clearer. L.B. Bohle offers a range of fluid bed granulation systems suitable for both small-scale production and production-scale research and development.

Video Credit: L.B. Bohle Maschinen und Verfahren GmbH

Granulation with the Bohle Fluid Bed Granulator

L.B. Bohle uses the Bohle Uni Cone BUC^® process to optimize fluid bed

The patented Bohle Uni Cone BUC^® is a slotted air distributor plate with a conical displacement cone. This configuration ensures comprehensive fluidization of particles. The resultant tangential motion of particles facilitates the formation of a uniform film, for example, on pellets, without the occurrence of twins.

Since the fluidized particles or granules move tangentially at relatively low fluidization height, they do not require a high-volume expansion. This efficiency translates into a reduced requirement for installation height, saving both space and costs on the production floor.

The BFS system includes a minimum of six filter elements, each of which can be individually cleaned to ensure a constant airflow through the product bed.

Drying, granulation, and coating without the need for alteration

Another advantage of the tangential design of L.B. Bohle facilities is that granulation, coating, and drying can all be performed in one system, eliminating the need to reconfigure equipment between processes.

Comparison of fluidized bed equipment

Groundbreaking Bohle Uni Cone BUC^®-Technilogy. Image Credit: L.B. Bohle Maschinen und Verfahren GmbH

Ordinary Wurster Process. Image Credit: L.B. Bohle Maschinen und Verfahren GmbH

Benefits Bohle Uni Cone BUC^®

• Effective air distribution: Quite narrow particle size distribution and formation of spherical granules
• Frameless product bottom plate design: Fast and simple cleaning
• Inspection of air plenum through the back pipe: Cross-contamination prevention in the bowl inlet
• Filter inspection: Safe position for the operator to stand on the floor
• Handling of the bottom plate: Safe de-installation in combination with an in-wall built lifting column

Bohle Uni Cone BUC^® Tangential Spray. Image Credit: L.B. Bohle Maschinen und Verfahren GmbH

Image Credit: L.B. Bohle Maschinen und Verfahren GmbH

Benefits of the fluid bed granulator

• Lowering of filters via electric drive
• Complete fluidization of particles
• Pressure surge resistance up to 12 bar- optimum conditions for containment applications
• Patented filter cleaning – patented diffuser
• Even film coating, no twin formation
• Low installation height, efficient space utilization
• Integration of PAT, NIR, and WIP
• Easy-to-remove distributor plate

Variations and technical features

Fluid bed systems are available from L.B. Bohle in various sizes and technological configurations.

The following list gives an overview and comparison of the various fluidiz bed units used for granulation.

Source: L.B. Bohle Maschinen und Verfahren GmbH