Effect of temperature on gas-liquid dispersion in multi-impeller three-phase reactor

Power consumption, gas hold-up and critical impeller speed for just complete off-bottom solid suspension have been measured in a triple-impeller stirred tank of 0.476m diameter with dished base under six different temperatures from 24℃ to 95℃. The impeller combination consisted of a half elliptical disk turbine (HEDT) as the bottom and two up-pumping wide-blade hydrofoils (WHU) above HEDT. The results show that temperature has a great effect on the hydrodynamic characteristics. Relative power demand (RPD) increases for the higher temperature, but the effect of temperature on RPD becomes weaker when more solids added in the system. Gas holdup decreases apparently with the increasing of temperature, which becomes less at higher solid concentration. The results and the correlations are of particular relevance to the design and operation of hot sparged three-phase reactors.