Prediction of Minimum Spout Velocity and Moisture Distribution of Ammonium Perchlorate Particles in a Spouted Bed Dryer

Document Type: Research Note

Authors

Department of Chemical Engineering, Amirkabir University of Technology, P.O. Box 15875-4413 Tehran, I.R. IRAN

Abstract

Ammonium perchlorate particles have been dried in a laboratory spouted bed dryer (screen-bottomed type) which is categorized as a fluidized bed dryer. The solid particles obtained in this process of drying were semi-porous and known as the group D of Geldart classification. The variations of moisture content with resident time, the effects of bed height on the pressure drop, and the influence of moisture content on drying rate were investigated. In this project, the air flow rate and the moisture diffusivity were determined. A model to determine the minimum spout velocity and also a model based on the Fick’s law were obtained which predicted the experimental data very well.

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