Drying in a Pulsed-Fluid Bed with Relocated Gas Stream

ABSTRACT

Results of studies on cooling and drying of powdery and granulated material in a pulsed-fluid bed ( PFB) system with relocated gas stream presented here are related to hydrodynamics and kinetics of these processes. Generalized results in the form of dimensionless equations can be used to determine basic process parameters such as drying time, heat transfer coefficient, pulsed-fluidzation velocity. pressure drop, etc. Results of experimental investigations, supplemented with experiments carried out in a prototype industrial equipment, can be useful for dryer scale-up and are recommended for designing.

A comparison of technical and economic parameters of these dryers with the parameters of classical fluid-bed dryers shows many advantages of PFB systems, including, among othen. reduced gas consumption, uniform bed structure and stability of final parameters of the product.

Positive estimation of the operation and technological parameters suggests that PFB dryers with relocated gas stream can be applied successfully in industrial practice.

Keywords and Phrases:

• pulsed-fluid bed
• hydrodynamics
• drying kinetics;
• pulsed-fluid bed dryers