An Understanding of the Relationship Between Mixing Performance and Power Consumption in a High-Shear Wet Granulation Pre-mixing

Introduction High-shear wet granulation (HSWG) is most commonly used in the pharmaceutical industry, with the advantages of being fully enclosed, having a good mixing effect, and being highly efficient. However, only a few studies are geared toward an in-depth understanding of the pre-mixing process in the high-shear wet granulator (HSWGr). Objectives In this paper, the effect of impeller speed and fill level on the mixing performance of particles is investigated using the discrete element method (DEM), which provides theoretical references for the energy-saving operation in HSWGr. Methods Relative standard deviation (RSD) was used as a mixing index to quantify mixing quality, particle temperature over a vertical distance to quantify particle motion bias, and total power consumption per unit mass to monitor the loss effect. Results The simulation results show that the impeller speed only affects the mixing process and does not change the mixing uniformity; the fill level has a significant effect on the particle mixing, and a higher fill level will inhibit the particle mixing; based on the uniform mixing, the fill level has little effect on the total power consumption per unit mass. Conclusion The results of the study show that increasing the fill level and impeller speed contributes to the energy-saving operation of HSWGr.