Patent ID: 8628601

Claim:
A process for the recovery of carbon dioxide from a gas mixture, the process comprising: pretreating a gas mixture comprising carbon dioxide, water vapor, and one or more light gases in a pretreating system to form a cooled gas mixture; fractionating the cooled gas mixture to recover a bottoms fraction comprising carbon dioxide and an overheads fraction comprising carbon dioxide and the light gases; contacting at least a portion of the bottoms fraction via indirect heat exchange with the overheads fraction to form an overheads vapor fraction and an overheads liquid fraction; passing the overheads vapor fraction over a membrane selective to carbon dioxide to separate a carbon dioxide permeate from a residue gas comprising the light gases; recycling the carbon dioxide permeate and the at least a portion of the bottoms fraction to the pretreating system; and recovering at least a portion of the bottoms fraction as a purified carbon dioxide product stream.