SPOUTED BED AND SPOUT FLUID BED BEHAVIOR IN A COLUMN OF DIAMETER 0.91-M

Hydrodynamic measurements were obtained in a half-column of diameter 0.91 m equipped with a conical base using particles of diameter 3.3 to 6.7 mm with operation both as pure spouted beds and in the spout-fluid bed mode. Comparison of the experimental results for minimum spouting velocity with equations in the literature generally gave unsatisfactory agreement. On the other hand, the cor-relations of McNab (1972) and Hadzisdmajlovic et al. (1983) gave reasonable predictions of spout diameters in spouted and spout-fluid beds respectively. Hydrodynamic regimes with auxiliary air present were broadly similar to those determined in smaller columns. However, there were substantial dead regimes at the bottom of the column. A finite difference model based on the vector form of the Ergun equation gave good predictions of air flow distribution and longitudinal pressure profiles.