Patent ID: 7152430

Claim:
A method of separating CO 2 from a hydrocarbon inlet gas stream that is within predetermined pressure and temperature ranges, comprising the steps of: (a) subjecting the inlet gas stream to fractional distillation in a distillation column providing a bottom product stream and a distillation overhead stream; (b) passing the distillation overhead stream from step (a) to a membrane unit producing a hydrocarbon stream and a by-product stream; (c) passing the hydrocarbon stream from step (b) to a hydrocarbon separator to separate hydrocarbon liquid having been condensed in said membrane unit from hydrocarbon vapor; and (d) subjecting the hydrocarbon vapor from step (c) to cooling providing a cooled hydrocarbon vapor stream that is fed to a reflux drum; and (e) taking a reflux liquid stream from said reflux drum and a hydrocarbon gas product stream.