(130b) Impact of Combined Distributive Mixing Elements and Kneading Elements on Granules Produced By Twin Screw Granulation

Impact of Combined Distributive Mixing Elements and Kneading Elements on Granules Produced by Twin Screw Granulation

Nathan B. Davis¹, Carl R. Wassgren¹

¹School of Mechanical Engineering, Purdue University, Indiana, USA

The screw elements conventionally used for twin screw granulation (TSG) are conveying elements and kneading elements. The use of kneading elements results in significant tradeoffs between the granule shape and liquid distribution. The use of distributive mixing elements has been show to improve the granule shape while also increasing granule porosity. The flexibility of the TSG means that producing granules with desirable size, shape, and porosity should be possible by combining the use of kneading elements and distributive mixing elements in an appropriate configuration.

In this work, the effects of combining both kneading elements and distributive mixing elements in order to produce rounded granules with a target size and porosity are presented. The kneading elements are tested in both the 60 degree forward and 30 degree reverse configuration to cover different levels of liquid distribution. The distributive mixing elements are placed downstream of the kneading elements and are in the adjacent reverse configuration.