CRITICAL GAS VELOCITY REQUIRED FOR COMPLETE SUSPENSION OF SOLID PARTICLES IN SOLID-SUSPENDED BUBBLE COLUMN WITH DRAUGHT TUBE

The critical gas velocity required for complete suspension of solid particles was studied experimentally in a solid-suspended bubble column with a draught tube. It was shown that the critical gas velocity increases with increasing terminal velocity of a single particle, solid concentration, liquid surface tension, diameter of gas distributor and density difference between solid and liquid, and decreases with increasing column diameter and liquid viscosity. Based on these observations, an empirical equation for critical gas velocity is proposed that is applicable to columns with diameters of 0.1-0.3 m.