STUDIES ON TRANSFER PROCESSES IN MIXING VESSELS - EFFECT OF PARTICLESON GAS-LIQUID HYDRODYNAMICS USING MODIFIED RUSHTON TURBINE AGITATORS

The work presents the effect of solid particles having a mean diameter between 15-1000 mu m, on the gas dispersion in a mechanically agitate d vessel with standard and modified Rushton turbine agitators position ed singly or doubly on same shaft. For the dispersing and uniform dist ribution of the three phase (gas-liquid-solid) through the entire vess el section, the modified blade turbines, with the surface fraction of the perforations equal to 0.353, were found to be more efficient, the power consumption being reduced by approximately 50% in comparison wit h the standard Rushton turbines. The power number in the turbulent mix ing of the three phase system is dependent on the aeration rate, the s urface fraction of the perforations, the turbine number and the physic al and rheological properties of the suspensions.