Optimum particle size and air flow rate in bubble separation of isoelectric casein coagula [in food processing waste water]

The adsorption equilibrium between air bubbles and isoelectric coagula of casein was affected by the superficial air velocity and particle size of coagula. An increase in the superficial air velocity V s increased the affinity between the air bubbles and casein particles, but decreased the maximum surface concentration. On the other hand, an increase in particle size d p decreased the affinity, but increased the maximum surface concentration. The optimum operating conditions of V s and d p existed because of the conflicting effects of them. These results also explain the selective separation of particles of different sizes.