Method of separating acetylene from methane cracking gases

Claim 1

A PROCESS FOR THE SEPARATION AND RECOVERY OF THE CONSTITUENTS OF A GASEOUS MIXTURE OBTAINED FROM A PARTIALLY COMBUSTION OF METHANE WHEREBY THE ACETYLENE AND CARBON DIOXIDE CONSTITUENTS OF THE MIXTURE ARE RECOVERED SUBSTANTIALLY PURE, SAID PROCESS COMPRISING COMPENSSING THE GASOUS MIXTURE TO ABOUT 13 ATM., COOLING TO A TEMPERATURE OF THE ORDER OF -80*C. IN A MULTIPLE STAGE DURATION INCLUDING THE REMOVAL OF CONDENSED MOISTURE FROM THE ADDITION OF A FIRST PORTION ACETALDEHYDE AS SELECTING SOLVENT, SUBJECT A RISING FLOW OF SAID ADMIXTURE FOR SCRUBBING AND ABSORBING ACTION OF A COUNTERCURRENTLY APPLIED SECOND PORTION OF SAID SOLVENT WHICH, ALREADY RICH ACETYLENE, SELECTIVELY ABSORBS HIGHER ACETYLENES AND ADDITIONAL ACETYLENE, SUBJECTING THE RISING VAPORS TO A SCRUBBING AND ABSORBING ACTION OF A COUNTERCURRENTLY APPLIED THIRD AND LARGER PORTION OF SAID SOLVENT WHICH HAS BEEN COOLED TO A TEMPERATURE SLIGHTLY ABOVE THE FREEZING POINT OF ACETYLENE AND WHICH COMPLETELY ABSORBS THE REMAINING ACETYLENE AND THE CARBON DIOXIDE OF SAID GASEOUS MIXTURE, SEPARATING THE SCRUBBED GASEOUS MIXTURE INTO A CARBON MONOXIDE AND HYDROGEN FRACTION, A METHANE FRACTION WHICH IS RECYCLED FOR COMBUSTION, AND AN ETHYLENE FRACTION, LIBERATING SAID COUNTERCURRENTLY APPLIED SECOND SOLVENT PORTION OF HYDROGEN, CARBON MONOXIDE, METHANE AND NITROGEN BY DEGASSING THROUGH PRESSURE RELEASE AND RECOVERING ACETYLENE AND CARBON DIOXIDE BY HEATING AND REFLUXING SAID SECOND SOLVENT PORTION, LIBERATING SAID COUNTERCURRENTLY APPLIED THIRD SOLVENT PORTION OF THE LESS SOLUBLE GASES HYDROGEN AND CARBON MONOXIDE AS WELL AS OF INERT GAS BY DEGASSING THROUGH PRESSURE RELEASE, RECOVERING THE MAIN PORTION OF ACETYLENE AND CARBON DIOXIDE BY HEATING TO ABOUT 30*C. AND REFLUXING SAID THIRD SOLVENT PORTION, SEPARATING THE CARBON DIOXIDE FROM ACETYLENE, PARTLY COOLING SAID THIRD SOLVENT PORTION AFTER HAVING BEEN FREED OF HYDROGEN, CARBON MONOXIDE, ACETYLENE AND CARBON DIOXIDE IN A HEAT EXCHANGE WITH PARTS OF SAID THIRD SOLVENT PORTION WHICH HAVE NOT BEEN HEATED AND REFLUXED AS YET, COMPRESSING TO THE INITIAL PRESSURE OF ABOUT 13 ATM., COOLING ONE PART OF THE COMPRESSED SOLVENT TO A TEMPERATURE OF THE ORDER OF -80* C., ADDING SAID COOLED AND COMPRESSED SOLVENT AS PART OF SAID COUNTERCURRENTLY APPLIED THIRD SOLVENT PORTION, COMBINING THE BALANCE OF SAID PARTLY COOLED AND COMPRESSED SOLVENT WITH SAID HEATED SECOND SOLVENT PORTION, LIBERATING THIS COMBINED FRACTION OF MOST OF THE HIGHER ACETYLENES BY MEANS OF PASSING METHANE THROUGH SAID COMBINED FRACTION AND SUBJECTING THE GASEOUS DISCHARGE TO CRACKING AND RECYCLING, HEATING THE REMAINING SOLVENT WHILE PARTIALLY REFLUXING, CONDENSING RECTIFIED SOLVENT VAPORS IN HEART EXCHANGE WITH WATER, COMPRESSING TO ABOUT 13 ATM., COOLING TO ABOUT -90*C. AND USING SAID COMPRESSED SOLVENT AT ABOUT -85*C. AS SAID COUNTERCURRENTLY APPLIED THIRD SOLVENT PORTION.