Experimental study of temperature effects on bubble characteristics and gas holdup in electroflotation column

The study of hydrodynamic in bubble column has widely caught the attention of several research studies. The hydrodynamic aspects in electroflotation column by using a model solution as oil/water emulsion were studied. In this paper the impact of current density, the physicochemical characteristics and temperature of liquid phase on hydrodynamic parameters were evaluated. A method of video image process was used to determine bubbles size, bubbles velocity and gas holdup. It was found that the different parameters depend on current density and oil concentration. The results reveal that bubble characteristics depend strongly on different factors. In fact bubble size increases when current density and oil concentration increase and it is controlled by coalescence/breakup phenomenon. Reynolds number is affected by current density and oil concentration and its increase gives rise to the appearance of turbulent regime. On the other hand, temperature has a significant effect on bubble size and gas holdup; however it does not have a significant effect on bubble rise velocity. A mathematical model was used to predict bubble's characteristics and the Reynolds number in order to characterize the different bubble flow regimes at fixed temperature.