Analyzing the mixing dynamics of a tumbling bin blender using discrete element modeling

Powder mixing is a critical step in pharmaceutical processes as it determines the final tablet composition. In this study a discrete element model (DEM) has been developed for an industrial scale tumbling bin blender in which three different materials are blended together. The dynamics of the mixing have been evaluated with the analysis of critical quality attributes (CQAs) such as relative standard deviation (RSD) and segregation intensity. This model has been developed and calibrated using an experimental setup in which the blend composition is monitored through a near-infrared range (NIR) probe mounted on the blender lid. The final blend quality is judged on the basis of measurements only at the lid in the experimental setup. However, the model has been used to study the quality of mixing in different locations inside the blender. The model is able identify poorly mixed zones and can be used to investigate other potential locations for the NIR probe. The effect of key process parameters (i.e. blender RPM and loading order of materials) on the quality of mixing has also been studied.M.S.Includes bibliographical referencesby Subhodh Kumar Karkal