Effect of Resonant Mixer Granulation Parameters on Prill Properties

ABSTRACT

Resonant mixing is a promising processing approach to manage mixing of materials with high solids content and has shown strong performance for mixing powders and pastes in energetic materials. This has led to the exploration of the approach for granulation of primary particles into millimeter‐sized agglomerates, including for generating energetic material prill. Despite some demonstrations of the ability to form prill, little work has been done to understand how the resonant mixing process parameters, such as the acceleration, applied vacuum, and mixing time, impact the properties of the prill. Here we systematically examine these process parameters through a design of experiments approach, evaluating the critical quality attributes including prill size, span, and roundness as well as the granule yield as the response variables. We find that the amount of time spent in the first stage where vacuum is applied, has a significant effect on the granule yield, while the magnitude of the vacuum in the second stage where vacuum is applied, is important for the particle size and roundness. We also examined the porosity in depth using microcomputed tomography, showing that a strong applied vacuum leads to a more porous prill. With these results, this study highlights key process parameters and provides future directions for optimization of resonant mixing granulation for different formulations.