Exploration of the dynamic attachment properties of oil droplets to air or condensate bubbles in flotation

Low flotation efficiency is the result of poor adhesion between oil droplets and air bubbles. The flotation of emulsified oil droplets can be improved by using bubbles coated with condensate. This study investigated the dynamic process of air/condensate bubble-oil droplet adhesion flotation and the flotation kinetic properties through experiments and theoretical models. The results show that the rupture of condensation bubbles with extraction effect is completed at 50/28 ms after collision with hydrophilic/hydrophobic oil droplets, and the oil droplets wrapped entirely on the surface of the condensate bubbles. In contrast, hydrophilic/hydrophobic oil droplets have a long liquid film thinning time (92/60 ms) after collision with air bubbles and form partially wrapped oil lenses after rupture. A modified Yoon-Luttrell model was suggested to clarify the relationship between bubbles and oil droplets. Finally, the flotation kinetic constant and induction time were calculated by the classical first-order kinetic model and the Finch model, respectively, and a fit was made to the relationship between the flotation rate constant, adhesion probability, and induction time(R-2>0.95). It provides an important theoretical basis for further optimisation of the condensate bubble flotation process.