Fluidized Bed Granulation Parameters Effect on Urea Granule Physical Properties

The aim of this study is to determine the effect of different airflow patterns and process conditions on the physical properties of granules produced using fluidized bed granulation technique. It was observed that spiral airflow was the most important factor to produce granules with required size and density under similar process conditions if compared with normal airflow. From ANOVA, binder spray pressure and bag shake duration showed the strongest influence on hardness of granules on both types of airflow patterns. Optimization studies for spiral and normal airflow proved that granules with desired density and hardness can be produced at middle level of wind velocity and binder spray pressure together with high level bag shake duration. For spiral airflow, the optimum value for wind velocity, binder spray pressure and bag shake duration was ۲۸ m/s, ۰.۳۱ MPa and ۶۰ s respectively; for normal airflow, it was ۲۵ m/s, ۰.۲۰ MPa and ۱۵ s respectively.

Keywords:

Air flow pattern , ANOVA , Spiral , Density , Bag shake duration , Hardness , Response surface methodology , Wind velocity , Binder spray pressure