Separation of steam and hydrocarbons

Claim 1

IN A PROCESS FOR THE PYROLYSIS OF A HYDROCARBON IN THE PRESENCE OF STEAM TO PRODUCE ETHYLENE ADMIXED WITH STEAM AND HIGHER BOILING HYDROCARBONS IN THE FORM OF A VAPOROUS PRODUCT STREAM, THE METHOD FOR MAKING AN EFFICIENT SEPARATION OF HYDROCARBON AND WATER WHICH COMPRISES PASSING SAID PRODUCT STREAM CONTAINING ETHYLENE, STEAM AND HIGHER BOILING HYDROCARBONS TO A RECTIFICATION ZONE, IN SAID RETIFICATION ZONE COOLING AND SEPARATING A LIQUID HIGHER BOILING HYDROCARBON PHASE AND A LOW BOILING VAPOR PHASE CONTAINING STEAM, ETHYLENE AND OTHER HYDROCARBONS, WITHDRAWING SAID LIQUID HIGH BOILING HYDROCARBON PHASE FROM THE RECTIFICATION ZONE, PASSING SAID LOW BOILING VAPOR PHASE FROM SAID RECTIFICATION ZONE TO A FIRST SEPARATION STEP MAINTAINED AT A RELATIVELY LOW PRESSURE LEVEL, IN SAID FIRST SEPARATION STEP COOLING SAID VAPOR PHASE TO FORM A WATER RICH PHASE, A LIQUID HYDROCARBON RICH PHASE AND AN UNCONDENSED VAPOR PHASE CONTAINING STEAM AND HYDROCARBON, PASSING SAID UNCONDENSED VAPOR PHASE FROM SAID FIRST SEPARATION STEP TO A SUBSEQUENT SEPARATION STEP MAINTAINED TO A SUBSTANTIALLY HIGHER PRESSURE LEVEL THAN SAID FRIST SEPATION STEP, PASSING SAID LIQUID HYDROCARBON PHASE FROM SAID FIRST SEPARATION STEP TO SAID SECOND SEPARATION STEP, IN SAID SUBSEQUENT SEPARATION STEP COOLING SAID VAPOR PHASE FROM SAID FIRST SEPARATION STEP TO FORM A WATER RICH PHASE, A LIQUID HYDROCARBON RICH PHASE AND AN UNCONDENSED HYDROCARBON PHASE, CONTAINING ETHYLENE, PASSING SAID WATER RICH PHASE FROM SAID SECOND SEPARATION STEP TO SAID FIRST SEPARATION STEP WHEREBY HYDROCARBONS ADMIXED THEREIN ARE FLASHED OFF AS THE RESULT OF DECREASE IN PRESSURE, WITHDRAWING WATER FROM SAID FRIST SEPARATION STEP, AND RECOVERING SAID UNCONDENSED HYDROCARBON PHASE CONTAINING ETHYLENE AND SAID LIQUID HYDROCARBON PHASE FROM SAID SUBSEQUENT SEPARATION STEP AS PRODUCTS OF THE PROCESS.