Model-Guided Development of a Semi-Continuous Drying Process.

Area of Science:

• Pharmaceutical Manufacturing
• Process Engineering
• Fluid Dynamics

Background:

• The ConsiGma® CTL25 wet granulation and tableting line is widely adopted in pharmaceutical continuous manufacturing.
• The semi-continuous six-segmented fluid bed dryer within this line is crucial for production.
• Observed repeatable patterns in drying times indicate variability in drying performance across the dryer's cells.

Purpose of the Study:

• To understand the root cause of drying performance variability in the six-segmented fluid bed dryer.
• To investigate the factors contributing to uneven drying times between different cells.

Main Methods:

• Experimental measurements of air temperature and airflow velocity in an empty dryer across its six cells.
• Interpretation of experimental data using computational fluid dynamics (CFD) simulations.

Main Results:

• CFD simulations identified the air inlet design as a significant factor influencing temperature distribution within the dryer cells.
• The simulations correlated with experimental observations regarding temperature differences between cells.

Conclusions:

• CFD simulations provide valuable insights into equipment performance variability, aiding process development and engineering decisions.
• While not predicting exact temperatures, simulations accurately reflected observed trends, highlighting their utility in troubleshooting.