Critical impeller speed for solid suspension in mechanically agitated contactors

Experiments were performed in mechanically agitated contactors with 6 (flat ) blade turbine impellers, to study the effect of various operating paramet ers on minimum/critical speed required for complete suspension in two-phase (liquid-solid) as well as three-phase (liquid-solid-gas) systems. Based on 1212 experimental measurements, a unified empirical correlation is propose d, for the estimation of minimum impeller speed for solid suspension in bot h two-phase and three-phase systems in terms of fundamental, operational an d geometrical variables.