CLARIFICATION OF YEAST BY COLLOIDAL GAS APHRONS

Colloidal gas aphrons or CGAs were employed in a flotation column for the recovery of yeast from aqueous solutions. The CGAs sparging rate w as a critical factor that governed the efficiency of the process. The separation efficiency was less than 30 % at a sparging rate of 1.3 ml sec(-1) and increased exponentially up to 90 % as the sparging rate wa s increased to 2.4 ml sec(-1). Whereas there was no appreciable change in the separation efficiency with CGAs sparging rates for high initia l feed concentrations, the maximum achievable efficiency decreased wit h an increase in the initial feed concentration. In general, a decreas e in pH will improve the separation efficiency.