Process for separation of hydrocarbon gases

A process for separation of a high pressure gaseous stream containing mixed light hydrocarbons which comprises:

• (a) expanding the high pressure gaseous stream to a first intermediate pressure and introducing the resulting expanded stream to a first single equilibrium separation zone;
• (b) recovering a first vapor stream and a separate first liquid stream from the first single equilibrium separation zone;
• (c) elevating the first liquid stream to a second intermediate pressure;
• (d) recovering refrigeration from the first liquid stream at the second intermediate pressure through indirect heat exchange by cooling the high pressure gaseous stream prior to its expansion thereby forming a revaporized stream from the first liquid stream at the second intermediate pressure and introducing the revaporized stream to a multi-equilibrium separation zone;
• (e) recovering and cooling an ethane-containing gaseous mixture from the multi-equilibrium separation zone;
• (f) introducing the cooled ethane-containing gaseous mixture to a second single equilibrium separation zone;
• (g) recovering a second vapor stream and a separate second liquid stream from the second single equilibrium zone;
• and
• (h) expanding the second liquid stream into the first single equilibrium separation zone.