Experiments were carried out on a pilot scale rotary kiln equipped with lifters at room temperature to investigate
the effects of thekilnslope,rotationalspeed,mass flow rateof materials,andexitdamheightonthehold-upand
the mean residence time (MRT). The MRT was determined from the residence time distribution measurements
asdetailedinPartIofthiswork.Twogranularsolidshavingdifferentpropertieswereused:sandandbrokenrice.
Furthermore, two shapes of lifters were compared to determine the influence of lifter geometry: straight lifters
(SL) and rectangular lifters (RL). A new model to predict the MRT was established by means of a dimensional
analysis. The correlation not only gave good agreement with the experimental data from the present study,
but also demonstrated good predictive performances when applied to published experimental data of other
kilns; the model is applicable for inclined kilns that process materials in cascading (tumbling) motion, whether
or not equipped with lifters or fitted with dams at the outlet end