Distillation column

Claim 1

A DISTILLATION COLUMN COMPRISING A CLOSED, VERTICAL GENERALLY-CYLINDRICAL SHELL FORMING A WALL, SAID WALL HAVING A FEED INLET AND PRODUCT OUTLET AND A PLURALITY OF SPACED APART, GENERALLY-CIRCULAR TRAYS VERTICALLY SPACED IN THE SHELL, SAID PLURALITY OF TRAYS BEING FREE OF ATTACHMENT TO THE WALL OF THE CYLINDRICAL SHELL AND VERTICALLY REMOVABLE FROM SAID SHELL, EACH OF SAID PLURALITY AND PLURALTY OF TRAY ING A SMALLER DIAMETER THAN THE INTERNAL DIAMETER OF THE SHELL SO THAT A CONTINOUS SMALL PERIPHERAL VAPOR PASSAGE MEANS IS PROVIDED EXTENDING UNINTERRUPTABLE PAST SAID PLURALITY OF TRAYS BETWEEN THE EDGES OF SAID PLURALITY OF TRAYS AND THE INTERNAL SHELL WALL, SAID PLURALITY OF TRAY EDGES AND SMALL PERIPHERAL VAPOR PASSAGE MEANS BETWEEN SAID TRAY EDGES AND SAID INTERNAL SHELL WALL CONSTITUTING BUBBLING ZONES IN WHICH VAPOR ASCENDS THROUGH LIQUID HELD ON THE RESPECTIVE TRAYS, SUPPORTING MEANS FOR SAID TRAYS, SAID SMALL PERIPHRAL VAPOR MEANS BEING SUFFICIENTLY SMALL TO HOLD LIQUID ON SAID PLURALITY OF TRAYS WHEN SAID VAPOR ASCENDS, SAID TRAYS BEING PROVIDED WITH AN OPENING IN ITS MID-SECTION AND A WEAR EXTENDING ABOVE ITS RESPECTIVE TRAY SURROUNDING SAID OPENING AND A RECEIVER FOR TRANSPORTING DECENDING LIQUID TO THE NEXT LOWERMOST TRAY.