Carbon Dioxide Removal Process

A process for recovering carbon dioxide from a pressurized hydrocarbon containing feed stream, the process comprising the steps of:

• a) introducing a high pressure hydrocarbon containing feed stream that comprises at least methane and carbon dioxide into a first membrane separation unit at a temperature that is above the liquefaction temperature of carbon dioxide, the first membrane separation unit containing one or more membranes that are selective for carbon dioxide over the other components in the hydrocarbon containing feed stream, each membrane having a permeate side and a residue side and allowing for the passing of carbon dioxide to the permeate side to form a first membrane stream on the permeate side of the membrane and the substantial retention of the remaining components in the hydrocarbon containing feed stream to form a second membrane stream on the residue side of the membrane;
• b) withdrawing the second membrane stream for further use;
• c) compressing the first membrane stream;
• d) cooling the compressed first membrane stream using a multi-stream heat exchanger in order to form a compressed, cooled two phase first membrane stream;
• e) separating and purifying the compressed, cooled, two phase first membrane stream in a carbon dioxide separation unit to produce a carbon dioxide rich liquid stream and a carbon dioxide lean vapor stream;
• f) recycling the carbon dioxide rich liquid stream to the heat exchanger where the carbon dioxide rich stream is used to provide cooling of the first membrane stream thereby producing a warmer carbon dioxide rich liquid stream;
• and
• g) recovering the warmer carbon dioxide rich stream from the heat exchanger as a high purity carbon dioxide product.