Modelling bubble–particle interaction with dynamic surface tension

Bubble–particle interaction in turbulent flow is a dynamic process by its very nature. Important flotation parameters such as air hold-up, bubble size distribution, and bubble–particle interaction are strongly influenced by the shape and behavior of bubbles in turbulent flow. Bubble dynamics and the behavior of the three-phase interface are determined by the local surface tension and surfactant mass transfer characteristics. For systems with homogeneous distribution of surfactants the Marangoni term vanishes from the balance of bubble surface forces. In flotation however the heterogeneity of spatial and temporal distribution of surfactants requires reformulation of the interfacial stress balance and inclusion of the Marangoni effect. In this paper we propose a method for dynamic modeling of surface tension forces in flotation systems. The understanding of bubble and surfactant dynamics can contribute to greater insight in the physico-chemical behavior of flotation systems.