Vacuum distillation of oils

Claim 1

A VACUUM DISTILLATION PROCESS COMPRISING HEATING AN OIL TO BE VACUUM DISTILLED, TO AN ELEVATED TEMPERATURE; PASSING OIL THUS HEATED INTO A SEPARATION ZONE TO SEPARATE ANY VAPORS THEREFROM; WITHDRAWING UNVAPORIZED OIL FROM SAID SEPARATION ZONE TOGETHER WITH RESIDUAL DISTILLATION PRODUCT ADMIXED THEREWITH AS DESCRIBED HEREINAFTER; INTRODUCING OIL THUS WITHDRAWN INTO A VACUUM DISTILLATION ZONE UNDER FLASHING CONDITIONS SO AS TO VAPORIZE A PORTION OF SAME, RESULTING RESIDUUM OIL SETTLING IN SAID DISTILLATION ZONE; CONDENSING VAPORS FORMED DURING SAID FLASHING AND RECOVERING RESULTING CONDENSATE; PASSING A PORTION OF OIL RESIDUUM FROM THE ZONE OF SAID FLASHING INTO ADMIXTURE WITH HEATED OIL IN SAID SEPARATION ZONE IN AN AMOUNT AND AT A CONTROLLED RATE OF FLOW SO AS TO QUENCH SAID HEATED OIL THEREIN TO A TEMPERATURE BELOW WHICH INCIPIENT CRACKING OF SAME TAKES PLACE, AND TO ACT AS A HEAT CARRIER DURING SAID FLASHING; AND RECOVERING A REMAINING PORTION OF SAID RESIDUUM.