Bed Voidage and Heat Transfer in Non-Newtonian Liquid-Solid Fluidized Bed

Document Type: Research Article

Authors

1 Department of Chemical Engineering, Isfahan University of Technology, Isfahan, I.R. IRAN

2 The university of Petrileum Industry, Ahwas, I.R. IRAN

Abstract

The presence of particles in liquid-solid fluidized beds enhances the bed heat transfer, because the movement of the particles leads to an increased turbulence in the system. Moreover, the violent movement of the particles has a positive effect on fouling of the heat transfer surface. The aim of this investigation was to perform systematic measurements of bed voidage and heat transfer coefficient for solid-liquid fluidization in a cylindrical tube and to study the effect of process parameters such as particle size and density, flow velocity, and liquid viscosity on these subjects. A large number of experiments were performed using different cylindrical and spherical particles fluidized in aqueous CMC solution with different concentrations. Using the experimental results, a new correlation for predicting heat transfer coefficient in non-Newtonian liquid-solid fluidized bed heat exchanger was introduced.

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