Recycling

Biography

Biography: Ben Mansour

Abstract

Electroflotation is a type of bubble columns. It is the electrochemical version of traditional dissolved air flotation. It is characterized by its mechanism of oxygen and hydrogen bubble formation due to water electrolysis. Electroflotation presents several advantages: - Silent process which does not require large amount of energy. - High removal efficiency of suspended solids. - High COD abatement rate by native oxygen bubbles formed at the anode. - Possible control of mass and size of bubble produced by simple adjustment of current density. - Possible use of solar energy as a power source. In this context and as a first step, our research team focused on electroflotation as water treatment process. Many applications were performed successfully on real industrial wastewaters with good results in both batch and continuous regime. Theoretical study of oxygen transfer and also bubble hydrodynamics in such bubble unit is therefore very useful to optimize the process of electroflotation. In this context, several studies also focused on different parameters which affect the mass transfer coefficient Kla such as agitation, temperature, nature of the regime (batch or continuous), current density applied to the electrodes of the unit. These studies allow us to better understand and optimize the phenomena of oxygen transfer. On the other hand, the effect of physicochemical characteristics of liquid phase on the hydrodynamics of the unit was also done. Of course, the knowledge and characterization of hydrodynamics are essential for several reasons. In fact, identifying areas of transition between laminar and turbulent regime can help us to optimize the process in case of use as water treatment process. In addition, the knowledge of hydrodynamic parameters such as bubble diameter or gas retention will also allow a better understanding of mass transfer phenomena.