A MODEL FOR CONTINUOUS FOAM CONCENTRATION OF PROTEINS - EFFECTS OF KINETICS OF ADSORPTION OF PROTEINS AND COALESCENCE OF FOAM

A model for Concentration of proteins from dilute solutions in a conti nuous foam fractionation column is proposed. This model accounts for ( 1) kinetics of adsorption of proteins in the liquid pool as well as in the foam, (2) liquid drainage from thin films due to Plateau border s uction and disjoining pressure, (3) gravity drainage of liquid from Pl ateau borders, and (4) bubble coalescence in the foam. Protein enrichm ent and recovery were found to increase as the liquid pool height incr eased, eventually attaining constant values (corresponding to adsorpti on equilibrium), thus demonstrating the strong dependence of protein s eparation on adsorption kinetics. Higher enrichments and lower recover ies were obtained for smaller gas velocities, larger bubble sizes, and higher feed flow rates. Enrichments as well as recoveries were higher at lower feed concentrations. Coalescence was found to lead to higher enrichments and lower recoveries, this dependence being stronger for larger inlet bubble sizes.