It is important that moisture levels are accurately maintained throughout the wet granulation or drying process within the fluid dryer.? This ensures consistent product formation in the tableting and pelletizing processes, which follow and ensure the effectiveness of the drug.? Continual monitoring and control of moisture will increase productivity and maximize the efficiency of the operation.
Pharmaceutical Manufacturing Processes
Granulation Process: A water based solution is slowly sprayed onto the excipients to ensure even distribution.? Air is simultaneously pumped through the bed of powder to gently lift and mix the ingredients.
Drying Process: This commences after the aqueous solution has been added (when preceded by a granulation operation).? When the batch reaches the desired moisture content, the air shuts off and the bowl of powder is transferred to the next operation.
Measurement and Location
Traditionally, moisture content is approximated by measuring the temperature of the exiting air.? This can prove unreliable as it is dependent upon the relative humidity and temperature of the incoming air.? To further confirm that the moisture has reached the required level, a sample is removed for laboratory testing.
Using the MCT 360? NIR on-lin moisture analyzer, moisture can be measured instantaneously “in situ” by using either a sappire viewing window, or a probe with an air purge to ensure non-adherence of product to the window.? Alternatively, if there are multiple flid bed dryers, an MCT600 laboratory instrument can be set up on a cart and transported to each Dryer in order to obtain instantaneous readings on samples extracted from the bowl.