Fractional crystallization process and apparatus

Claim 1

IN A PROCESS FOR SEPARATING A COMPONENT FROM A LIQUID MULTICOMPONENT MIXTURE WHICH COMPRISES INTRODUCING SAID MIXTURE INTO A CRYSTAL FORMING ZONE, COOLING SAID MIXTURE IN SAID ZONE SO AS TO FORM A SLURRY OF CRYSTALS OF SAID COMPONENT IN MOTHER LIQUOR, CENTRIFUGING SAID SLURRY SO AS TO REMOVE MOTHER LIQUOR THEREFROM AND FROM A CAKE OF SAID CRYSTALS, AND RECOVERING SAID CRYSTALS AS A PRODUCT OF THE PROCESS, THE IMPROVEMENT COMPRISING MELTING AT LEAST A PORTION OF SAID RECOVERED CRYSTALS, HEATING A PORTION OF THE RESULTING MELT TO A TEMPERATURE IN THE RANGE FROM 100* TO 250*F. ABOVE THE MELTING POINT OF SAID COMPONENT, PRIOR TO RECOVERING SAID CRYSTALS, SUPPLYING HEATED MELT TO THE SURFACE OF SAID CRYSTAL CAKE AT A PREDETERMINED RATE WHILE CENTRIFUGING SAID CAKE, CONTINUOUSLY MEASURING THE CONCENTRATION OF SAID COMPONENT IN SAID MIXTURE, AND ADJUSTING THE RATE AT WHICH SAID HEATED MELT IS SUPPLIED TO SAID CRYSTAL CAKE IN DIRECT PROPORTION TO AND IN RESPONSE TO VARIATIONS IN SAID MEASURED CONCENTRATION OF SAID COMPONENT IN SAID MIXTURE.