Effect of lifter shape and operating parameters on the flow of materials in a pilot rotary kiln: Part IV. Improvement of the hydrodynamics-related dimensionless correlations

Abstract

Non-spherical particles are widely processed in industrial-scale rotary kilns. There is nonetheless a lack of simple tools that make it possible to predict their hydrodynamic behavior inside rotary kilns. This article thus focuses on the hydrodynamics of crozets flowing inside a pilot-scale rotary kiln. Thirty-eight experiments were conducted with this product. Experimental Residence Time Distribution curves were successfully obtained with a tracer pulse methodology using painted crozets. Both the experimental mean residence time and the axial dispersion coefficient were obtained by fitting the analytical expression of E(t) for the open-open boundary condition with the experimental E(t) curves. The hydrodynamic behavior observed was qualitatively in agreement with the literature. Our dimensionless models were then re-identified with all of the experimental data and simplified through statistical analysis. This study provides more robust dimensionless hydrodynamic models that can be used to reliably predict the behavior of non-spherical particle flow inside an industrial kiln.