Continuous fractional crystallization process

Claim 1

A FRACTIONAL CRYSTALLIZATION PROCESS FOR SEPARATING A COMPONENT IN SUBSTANTIALLY PURE FORM FROM A LIQUID MIXTURE CONTAINING SAID COMPONENT WHICH COMPRISES CHARGING SAID MIXTURE INTO A FILTRATION ZONE OF A PROCESS FLOW CONSISTING OF FOUR SERIALLY INTERCONNECTED ZONES, INCLUDING SAID FILTRATION ZONE, PRIMARY RECTIFICATION ZONE DOWNSTREAM ADJACENT TO THE FILTRATION ZONE, A CRYSTAL MELTING ZONE DOWNSTREAM ADJACENT TO THE PRIMARY RECTIFICATION ZONE AND A SECONDAY RECTIFICATION ZONE DOWNSTREAM ADJACENT TO THE MELTING ZONE AND HAVING ITS OUTLET END IN COMMUNICATION WITH THE INLET END OF SAID FILTRATION ZONE, EACH OF SAID ZONES CONTAINING A FILTER MEDIUM, COOLING SAID LIQUID MIXTURE BY HEAT EXCHANGE WITH A COOLANT AND PRECIPITATING IN SAID FILTRATION ZONE CRYSTALS OF ONE OF THE COMPONENTS OF SAID MIXTURE IN MOTHER LIQUOR COMPRISING AT LEAST ONE OTHER COMPONENT OF THE MIXTURE, WITHDRAWING A PORTION OF THE MOTHER LIQUOR STREAM FROM AN OUTLET AT THE DOWNSTREAM END OF SAID FILTRATION ZONE SIMULTANEOUSLY REFLUXING A REMAINING PRIMARY REFLUX PORTION OF SAID MOTHER LIQUOR STREAM INTO THE INLET OF SAID PRIMARY RECTIFICATION ZONE TO DISPLACE FROM THE FILTER MEDIUM IN THE LAST-NAMED ZONE MOLTEN CRYSTALS CONTAINED THEREIN FROM A PREVIOUS CYCLE OF OPERATION, CHARGING A STREAM OF RELATIVELY HOT MOLTEN CRYSTALS INTO THE INLET END OF THE CRYSTAL MELTING ZONE, WITHDRAWING A STREAM OF MOLTEN CRYSTALS FROM AN OUTLET AT THE DOWNSTREAM END OF SAID