Process for separation of gases

Claim 1

A PROCESS FOR REDUCING THE COOLING AND REFRIGERATION REQUIREMENTS IN THE SEPARATION UNDER ELEVATED PRESSURE AND REDUUCED TEMPERATURE OF A FLUID MIXTURE INCLUDING A SUBSTANTIAL PROPORTION OF HYDROCARBONS HAVING DIFFERENT BOILING POINTS INTO AN OVERHEAD PRODUCT AND A BOTTOMS PRODUCT IN WHICH AT LEAST ONE OF SAID PRODUCTS COMPRISING A MAJOR PROPORTION OF HYDROCARBONS IN A VERTICAL COLUMN TYPE SYSTEM HAVING A CONDENSING SECTION WITH A FLUID INLET OPENING INTO THE COLUMN BENEATH THE BOTTOM OF SAID SECTION AND A STRIPPING SECTION EXTENDING DOWNWARDLY FROM ADJACENT THE INLET TO THE LOWER PART OF THE COULMN, WHICH COMPRISES THE STEPS OF: COOLING THE FEED FLUID MIXTURE AT AN ELEVATED PRESSURE FROM AN AMBIENT TEMPERATURE TO A REDUCED TEMPERATURE BETWEEN ITS DEW POINT AND COMPLETE CONDENSATION WHEREIN SAID FLUID IS AT LEAST PARTIALLY CONDENSED, DELIVERING THE FEED MIXTURE INTO THE COLUMN BY MEANS OF THE INLET; SUPPLYING HEAT SUFFICIENT TO VAPORIZE SUBSTANTIALLY ALL OF THE LOWER BOILING POINT COMPONENTS, AT LEAST PART OF SAID HEAT BEING SUPPLIED BY INTRODUCING INTO THE BOTTOM PORTION OF THE STRIPPING SECTION A FLUID HEAT EXCHANGE MEDIUM IN INDIRECT HEAT EXCHANGE RELATION WITH, AND AT A TEMPERATURE SLIGHTLY ABOVE, THE TEMPERATURE OF THE MATERIAL IN THE BOTTOM OF THE COLUMN AT ITS POINT OF INTRODUCTION, SAID HEAT EXCHANGER MEDIUM CONSISTING OF AT LEAST A PART OF SAID FEED FLUID PRIOR TO ITS DELIVERANCE TO THE COLUMN, PROVIDING THEREBY A RISING VAPOR STREAM OF THE LOWER BOILING COMPONENTS AND A DESCENDING LIQUID STREAM OF THE HIGHER BOILING POINT COMPONENTS; CAUSING THE HEAT EXCHANGER MEDIUM TO RISE WITHIN THE COLUMN AND COOLING THE HEAT EXCHANGE MEDIUM BY HEAT EXCHANGE WITH THE VAPOR AND LIQUID COMPONENTS WITHIN THE COLUMN UNDER CONDITIONS SUCH THAT AT ANYS ECTION IN THE COLUMN WHERE SAID HEAT EXCHANGE MEDIUM IS PRESENT, SAID HEAT EXCHANGE MEDIUM, VAPOR AND LIQUID COMPONENTS ARE ALL IN SUBSTANTIAL TEMPERATURE EQUILIBRIUM WITH ONE ANOTHER, AND WITHDRAWING SAID HEAT EXCHANGE MEDIUM FROM THE COLUMN ADJACENTG THE INLET AT APPROXIMATELY THE REDUCED TEMPERATURE OF THE INCOMING MIXTURE OF FLUIDS.