MONITORING THE GRANULATION PROCESS IN A HIGH SHEAR MIXER GRANULATOR - AN EVALUATION OF 3 APPROACHES TO INSTRUMENTATION

A high shear vertical mixer/granulator was instrumented to monitor power consumption, direct torque and reactive torque. All three methods were used to determine their ability in describing the granulation operation. Of the three methods used, direct torque generated the most descriptive profile of the granulation process. Two formulations were manufactured making use of direct torque in detailing the massing process. End-points were determined and the granulations produced were shown to yield tablets with acceptable hardnesses. One formulation was intentionally overwetted and the change in direct torque monitored to demonstrate the ability of the transducer to detail the massing process. Large fluctuations in torque, during the terminal phase of granulating, were seen and related to the doughy consistency of the final product. It was concluded that torque measurements, preferably direct, are needed to more precisely define granulation end-points. These types of measurements are needed to optimize the granulation unit operation during product development.