Recovery of hydrocarbons from natural gas

Claim 1

A PROCESS FOR TREATING NATURAL GAS TO RECOVER NATURAL GASOLINE THEREFROM WHICH COMPRISES PASSING THE GAS UNDER PRESSURE COUNTERCURENT TO A LEAN ABSORPTION OIL TO DISSOLVE THEREIN GASOLINE AND PART OF THE LIGHTER COMPONENTS INCLUDING SOME METHANE, REJECTING UNDISSOLVED GAS, FLASHING LIGHT GASES FROM THE RESULTING RICH OIL IN A FIRST STAGE BY PRESSURE REDUCTION, SUBJECTING THE RESULTING OIL WITHOUT HEATING TO A SECOND PRESSURE REDUCTION TO FLASH ADDITIONAL LIGHT GASES THEREFROM, WITHDRAWING SAID ADDITIONAL LIGHT GASES AND SUBJECTING SAME TO REABSORPTION BY COUNTERCURRENT CONTACT WITH A LEAN ABSORPTION OIL, REJECTING UNDISSOLVED GAS FROM SAID REABSORPTION STEP, ADMIXING RICH ABSORPTION OIL FROM SAID REABSORPTION STEP WITH THE ABSORPTION OIL FROM SAID SECOND PRESSURE REDUCTION, HEATING THE ADMIXTURE TO A TEMPERATURE HIGHER THAN EMPLOYED IN SAID FIRST AND SECOND PRESSURE REDUCTIONS AND THEN SUBJECTING THE HEATED OIL TO A THIRD PRESSURE REDUCTION TO VENT ADDITIONAL LIGHT GASES THEREFROM, PASSING SAID ADDITIONAL LIGHT GASES TO CONTACT WITH ABSORPTION OIL IN THE AFORESAID REABSORPTION STEP, HEATING FLASHED RICH OIL FROM SAID THIRD PRESSURE REDUCTION TO A STILL HIGHER TEMPERATURE, SUBJECTING THUS-HEATED OIL TO A FOURTH PRESSURDE REDUCTION AND SEPARATING THEREFROM A METHANE-CONTAINING GAS WHICH IF MIXED WITH THE STILL VAPORS HEREINAFTER DESCRIBED WOULD REDUCE THE PERCENTAGE OF CONDENSATE FORMED WHEN SAID VAPORS ARE SUBJECTED TO PARTIAL CONDENSATION, SUBJECTING PARTIALLY DENUDED RICH OIL RESULTING FROM SAID SAID FOURTH PRESSURE REDUCTION AND WHICH CONTAINS A MAJOR PROPORTION OF SAID GASOLINE TO DISTILLATION AND DEPHLEGMATION TO PRODUCE AS BOTTOM PRODUCT A LEAN OIL AND AS OVERHEAD PRODUCT STILL VAPORS COMPRISING GASOLINE HYDROCARBONS, PARTIALLY CONDENSING THE DEPHLEGMATED STILL VAPORS TO PRODUCE A VAPOR FRACTION AND A LIQUID FRACTION, PUMPING SAID LIQUID FRACTION INTO A HIGH-PRESSURE ACCUMULATOR, COMPRESSING AND AT LEAST PARTIALLY CONDENSING SAID VAPOR FRACTION AND PASSING SAME INTO SAID HIGH-PRESSURE ACCUMULATOR, SEPARATELY COOLING AND COMPRESSING AND THEN PARTIALLY CONDENSING THE AFORESAID METHANE-CONTAINING GAS AND PASSING SAME INTO SAID HIGH-PRESSURE ACCUMULATOR, WITHDRAWING VAPORS FROM SAID HIGHPRESSURE ACCUMULATOR, AND WITHDRAWING LIQUID FROM SAID HIGH-PRESSURE ACCUMULATOR AND FRACTIONATING SAME TO RECOVER NATURAL GASOLINE THEREFROM AS A PRODUCT OF THE PROCESS.