PARTICLE-LIQUID MASS-TRANSFER IN MULTI-IMPELLER AGITATED 3-PHASE REACTORS

The mass transfer coefficient between solid particle and liquid has be en measured in high aspect ratio multiimpeller agitated three phase (g as-liquid-solid) reactors. Experiments were conducted in 0.15 and 0.30 m id acrylic columns of Im length each. Two types of impeller were us ed: disk turbine (DT) and pitched turbine downflow (PTD). Air used as the gas phase was introduced through a ring sparger of 0.8 D size loca ted 0.1T distance above the bottom. The interimpeller spacing was main tained at the tank diameter. The range of gas velocity used was 0-15 m m/s. A unique correlation between particle-liquid mass transfer coeffi cient and critical impeller speed for solid suspension has been presen ted.