APPLY DEM TO STUDY WET BINDER ADDITION AND DRY BINDER ADDITION WET GRANULATION IN A HIGH SHEAR GRANULATOR

Sheng-Wen Chen
2017 unpublished
Wet granulation is widely used in many industries especially in the pharmaceutical industry for its capability to improve flowability and handling of powder substances. A discrete element model (DEM) was developed to study two kinds of liquid addition methods in wet granulation in high shear granulator: wet binder addition (WBA) and dry binder addition (DBA). To define the complex interaction in the systems, liquid bridge model and powder penetration theory are applied to develop the contact
more » ... elop the contact model. The DBA system possesses ten times higher viscosity particles than the WBA system. The results of two systems were compared and differences in viscosity profile were identified. Viscous regions are found to move when time progressing. The relationship between impeller and viscosity profile are studied. The great difference in viscosity is related to strong liquid bridge force and average bridge number in the DBA system. The strong liquid bridge force results in larger granules in the DBA system. iii Acknowledgements I would like to show my gratitude to Dr. Rohit Ramachandran for offering me the opportunity to join his research group and work with all brilliant people on interesting projects. I want to thank Ashu Thamrakar for collaboration on the development of DEM model and support on the research. Without his help, I won't be able to make this thesis happen. I would also like to thank other members of the research group for providing suggestions on my work. Lastly,
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