Solvent recovery from plant off-gases

Claim 1

IN A COMMERCIAL SCALE OLEFIN POLYMERIZATION PROCESS EMPLOYING A HYDROCARBON HAVING FROM5 TO 1ICARBON ATOMS PER MOLECULE AS A PROCESS DILUENT WHEREIN PRESSURE RELIEF VALVES VENT EQUIPMENT INTO A COMMON PLANT OFF-GAS STEAM SUBJECT TO LARGE VARIATIONS IN FLOW, THE METHOD OF RECOVERING MAJOR QUANTITIES OF SAID DILUENT WHICH COMPRISES DIRECTING A SUBSTANTIALLY CONSTANT AMOUNT OF GAS FROM A FIRST POINT IN SAID OFF-GAS STREAM INTO AN ABSORPTION ZONE, CONTACTING SAID GAS IN SAID ABSORPTION ZONE WITH ABSORPTION OIL THEREBY ABSORBIN DILUENT PRESENT IN SAID GAS, PASSING THUS CONTACTED GAS FROM SAID ABSORPTION ZONE TO A SECOND POINT IN SAID STREAM, JPASSING OFF-GAS SUPPLIED TO SAID FIRST POINT IN EXCESS OF SAID CONSTANT AMOUNT JTO SAID SECOND POINT THERBY BYPASSING SAID ABSORPTION ZONE WITH EXCESS OFF-GAS, RECYCLING MAKE-UP JCONTACTED GAS FROM SAID SECOND POINT TO SAID FIRST POINT WHEN THE OFF-GAS SUPPLIED TO SAID FIRST POINT IS LESS THAN SAID CONSTANT AMOUNT THEREBY PROVIDING SAID CONSTANT AMOUNT OF GAS TO SAID ABSORPTION ZONE, PASSING ABSORPTION OIL FROM SAID ABSORPTION ZONE TO A STRIPPING ZONE, STRIPPING SAID ADSORPTION OIL TO REMOVE DILUENT THEREFROM, RECIRCULATING SAID ABSORPTION OIL FROM SAID STRIPPING ZONE TO SAID ABSORPTION ZONE, AND RECOVERING SAID DILUENT REMOVED IN SAID STRIPPING STEP.