Abstract: The present disclosure provides a system for recovering emissions generated from an olefin polymerization process, comprising: a devolatilizer for receiving a fresh sweep gas and emissions generated from the olefin polymerization process and outputting a first fluid and a polyolefin resin; a compression refrigeration unit including a compression device and a first heat exchange device, for receiving said first fluid and outputting a first gas-liquid mixture; a first gas-liquid separation device for separating the first gas-liquid mixture and outputting a first recovery product and a first gas phase composition; a first gas separation device for receiving the first gas phase composition, removing small molecular substances therefrom, and outputting a composition rich in small molecular gases and a second gas phase composition rich in hydrocarbons; and a second gas separation device having a second heat exchange device, a second gas-liquid separation device, and a first gas expansion device.