Comparative Evaluation of Existing Correlations to Predict Spouted Bed Hydrodynamics

Abstract

Spouted bed technology is highly dependent upon empirical correlations for design and modeling purposes. In order to carry out a state-of-the-art review on the hydrodynamic parameters needed for design and performance evaluation of spouted beds, a detailed analysis is made regarding the reliability of various hydrodynamic correlations of spouted beds reported in the literature. Spout diameter, maximum spoutable height, and minimum spouting velocity as critical hydrodynamic parameters are evaluated. Many correlations show poor predictions for calculating these parameters in certain operating conditions. Cecen's equation^{[ 1 ]} successfully predicts the maximum spoutable bed height for fine particles. For large particle diameters, the equation of Morgan and Littman^{[ 2 ]} is valid. The equations of McNab^{[ 3 ]} and Malek et al.^{[ 4 ]} for determining spout diameter and the equations of Grbavcic et al.^{[ 5 ]} and Mathur and Gishler^{[ 6 ]} for calculating the minimum spouting velocity are recommended. Although some researchers have tried to modify the old equation of Mathur and Gishler^{[ 6 ]} to improve its predictions of minimum spouting velocity, this equation is more successful than any other equation proposed yet for a wide range of operating conditions.

Keywords:

• Correlations
• Maximum spouted bed height
• Minimum spouting velocity
• Spout diameter
• Spouted bed

Notes

^a The original correlation was converted to SI units.

^a The original correlation was converted to SI units.

^a d _s which is required in the correlation of Littman et al.^{[ 29 ]} is calculated by the McNab correlation.^{[ 3 ]}

^a The first equation; that is, .

^b The second equation; that is, .