Oxygen transfer rate behavior in three phase electroflotation column

Abstract

The effects of bubble size, solids particle (impurities) and the respective physical mechanisms on gas–liquid columns have received little attention. Therefore, the objective of this work is to study the effect of solid concentration and the ratio of the bubble diameter to the solid diameter on the mass transfer characteristics. Experiments were conducted in a three phase electroflotation column for the systems gas/water/olive stone. Volumetric mass transfer coefficient, kLa, was measured under different solid concentrations values (1–3 g/l) and ratio of the bubble diameter to the solid diameter values. It was found that the kLa rises when the ratio of the bubble diameter to the solid diameter increase. The presence of solid particle has a negative effect on mass transfer coefficients (kLa,kL and a). The liquid side mass transfer coefficient has the same behavior as the volumetric mass transfer coefficient. The capacity of oxygenation CO was also studied. Models relating the mass transfer coefficients kLa, kL and CO were elaborated in each case using linear regression method.