Abstract
The critical gas velocity required for complete suspension of solid particles has been studied experimentally in solid-suspended bubble columns. It was shown that the critical gas velocity increases with increasing terminal velocity of a single particle, column diameter and the density difference between solid and liquid, and decreases with increasing liquid viscosity and liquid surface tension. It was also shown that the critical gas velocity decreases when a conical bottom is used instead of a flat one.
Based on these observations, an empirical correlation for critical gas velocity has been proposed that is applicable to columns with diameters of 0.1-0.3 m.
