Experimental study on the space time of flexible filamentous particles in a rotary dryer

Abstract Rotary dryers have been extensively employed across a wide range of industries. The space time of particles in a rotary dryer plays an important role in the drying process. Due to the lack of study on non-spherical particles in rotary dryers, this study focused on flexible filamentous particles and chose tobacco particles as experimental material. The bulk moment of particle and particle space time were investigated in a laboratory rotary drum with a conventional method. Moreover, the influences of rotational velocity, drum slopes, gas flow rate and material flow rate as well as material moisture content were discussed. Furthermore, a revised correlation of the key variables was proposed to estimate the space time to improve existing correlations and propose new correlations for flexible filamentous particles in the rotary drum. Experimental results could reveal the influence of the considered key variables on particle behavior and the space time: the increases of rotational velocity, gas flow rate and drum slope could reduce the space time, while the space time increases with the increases of material flow rate and moisture content. It is also found that the estimation results of the proposed method show good agreement with the experimental findings of the established system.