A STUDY OF PROCESS INTERACTIONS BETWEEN CELL DISRUPTION AND DEBRIS CLARIFICATION STAGES IN THE RECOVERY OF YEAST INTRACELLULAR PRODUCTS

The effects of varying the levels of cell disruption achieved by high- pressure homogenization upon subsequent centrifugal separation of cell debris have been defined by measuring sedimentation velocity distribu tions of the cell debris. Using this data together with particle size distributions, a computer-based model of a disk stack centrifuge has b een used to predict the efficiency of centrifugal separation. These pr edictions have been compared with both laboratory scale and pilot plan t scale experimental results. A similar sedimentation velocity techniq ue has been used to characterize the properties of the flocs formed by addition of poly(ethylene imine) to a borax-clarified homogenate supe rnatant. The variations of floc settling properties with respect to po lymer concentration are defined.