The granulation process begins by dry blending using the impeller. The PHARMX impeller utilizes blades mounted tangentially to the center hub with enlarged blade tips. The tangential mounting eliminates build up of product where the blade mounts to the center hub. The enlarged blade tips lift the material into a vortex.
Once the product is blended, liquid is added manually or automatically using a peristaltic pumping system or pressurized container. A pressure atomized spray nozzle distributes the liquid in the bowl to prevent wet spots.
After the liquid is added, the chopper (which is located in the side wall of the bowl) is started to shear the product and break down lumps. The tulip shaped chopper design on the PHARMX has a large amount of surface area spinning at high tip speeds, providing efficient granulating action.
The product is granulated until the desired granule size and density is achieved. End point detection is done via power or torque measuring of the main drive system.
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