A novel rotary dryer for drying fertilizer: Comparison of performance with conventional configurations

摘要

Conventional rotary dryers are used in many industrial sectors. They are equipped with flights, which lift the material and shower it down through the hot gas stream. A new rotary dryer was proposed and designed by our research group. This novel device, called a "roto-aerated dryer", is equipped with a central pipe (encased in the drum) from which a series of mini pipes carry hot air directly to the particle bed flowing at the bottom (without flights). In this study, the performances of conventional rotary dryers (for drying fertilizer), with concurrent and countercurrent flows, were compared with a roto-aerated dryer configuration in which a hybrid distribution of mini pipes was used. The results confirm the superior performance of the hybrid roto-aerated dryer when compared with conventional ones, due to the better gas-particle contact. The drying rate in the hybrid roto-aerated dryer was up to 18-fold higher than that found in the best configuration of the conventional rotary dryer (countercurrent flow). (C) 2014 Elsevier B.V. All rights reserved.