Bench to batch: Linking pharmaceutical powder flow characterisation, intermediate bulk container discharge and video...

Area of Science:

• Pharmaceutical Engineering
• Powder Technology
• Material Science

Background:

• Understanding powder flow behavior in Intermediate Bulk Containers (IBCs) is critical for efficient pharmaceutical manufacturing and material handling.
• Excipient properties significantly influence bulk behavior and flowability, impacting process design and predictability.
• Previous studies have highlighted challenges in achieving consistent powder discharge from bulk containers.

Purpose of the Study:

• To investigate the impact of different powder blends on flow dynamics within unvented Intermediate Bulk Containers (IBCs).
• To identify key factors influencing powder discharge rates and flow modes.
• To establish reliable methods for predicting powder discharge from IBCs.

Main Methods:

• Selected five excipients and a model drug substance with diverse particle properties for blend formulation.
• Utilized two pilot-scale unvented IBCs equipped with cameras for internal observation and catch balances for discharge rate measurement.
• Analyzed powder behavior, flow modes, and the necessity of air bursts for discharge.

Main Results:

• Powder flow from IBCs, irrespective of the flow mode, necessitates an air burst, analogous to emptying a bottle.
• Strong internal air flow was observed, potentially leading to fluidization segregation.
• Discharge curves for 15° and 30° hopper half angles showed similarity, attributed to vertical air movement in steeper hoppers reducing particle acceleration.
• Several indicators for flow/no-flow conditions were identified.
• A linear correlation was found between orifice flow and IBC discharge rate, proving useful for prediction.

Conclusions:

• Air bursts are essential for initiating powder discharge from IBCs, and their internal dynamics can cause segregation.
• Hopper angle has a limited impact on discharge rates due to counteracting air movement effects.
• Orifice flow measurement provides a reliable method for predicting IBC discharge rates, enhancing process control in powder handling.