Process and apparatus for purifying impure alcoholic liquid

Claim 1

IN THE PRODUCTION OF ETHANOL FROM AN IMPURE HYDROETHANOLIC LIQUID, THE COMBINED STEPS OF INTRODUCING SAID IMPURE LIQUID IN PREHEATED CONDITION INTO AN INTERMEDIATE POINT OF AN EXTRACTIVE DISTILLATION ZONE, FEEDING HOT AQUEOUS TAIN AN INTERNAL LIQUID REFLUX HAVING A HIGH WATER CONTENT IN SAID EXTRACTIVE DISTILLATION ZONE, AND TO DRIVE ETHANOL FROM SAID EXTRACTIVE DISTILLATION ZONE, AND TO DRIVE ETHANOL FROM SAID IMPUR ETHANOLIC LIQUID DOWN TO THE BASE OF HYDRCALCOHOLIC BOTTOMS INU SAID BASE, INTRODUCING THE BOTTOMS FFOM SAID EXTRACTIVE DISTILLATION ZONE INTO THE UPPER PART OF A STRIPPING ZONE HAVING A BOTTOM HEATING SECTION, SUPPLYING HEAT TO SAID BOTTOM HEATING SECTION, INTRODUCING A PORTION OF THE OVERHEAD VAPOURS FORM SAID STRIPPING ZONE INTO THE LOWER PART OF SAID EXTRACTIVE DISTILLATION ZONE, AND ANTOTHER PORTION INTO THE LOWER PART OF AN ALCOHOL CONCENTRATING, DISTILALTION ZONE CONTAINING A WATER ENTRAINER, TO PRODUCE AT AN INTERMEDIATE POINT IN THE LAST-NAMED ZONE, A TERNARY MIXTURE OF ETHANOL, WATER ENTRAINER AND WATER, SUBSTANTIALLY FREE FROM IMPURITIES AND HAVING A LOW WATER CONTENT, DRAWING OFF SAID TERNARY MIXTURE AS A SIDE-STREAM FROM SAID ALCOHOL CONCENTRATING, DISTILATION ZONE AND FEED-