Gas/liquid mass transfer in Technicolor

Characterization of mass transfer in gas/liquid systems is a challenging issue that arises in many practical applications. For instance, one of the main steps for treating wastewaters consists of transferring oxygen into those liquids through air/liquid interfaces (e.g., air bubbles). Oxygen is a key nutrient for microorganisms able to degrade pollutants contained in the wastewaters. Thus, its transfer is highly related to the process performance. Powerful techniques enable a direct visualization of this complex transfer phenomenon and are thus interesting tools for understanding the different mechanisms governing the mass transfer. The purpose of this presentation is to couple different visualization techniques to observe and quantify accurately both hydrodynamics and mass transfer near to gas/liquid interfaces at local scales to serve industrial purposes.