Patent ID: 8273152

Claim:
A method of separating a component from a feed gas stream comprising: introducing the feed gas stream to a retentate side of a membrane and separating the component from the feed gas stream such that the component collects at a permeate side of the membrane by establishing a positive partial pressure difference of the component between the retentate side and the permeate side; circulating a sweep stream to the permeate side of the membrane to at least in part establish the positive partial pressure difference and thereby form a component laden sweep stream; the sweep stream being formed by pumping the sweep stream in a liquid state to a supercritical pressure and then heating the sweep stream to a temperature level of no less than 100° F. below a supercritical temperature; the sweep stream being heated, at least in part, through indirect heat exchange with the component laden sweep stream, thereby to cool the component laden sweep stream and to form a two-phase stream from the component laden sweep stream having the component in a vapor phase thereof; cooling the two-phase stream such that a liquid phase of the two-phase stream is enriched in a substance making up the sweep stream and a vapor phase thereof is enriched in the component; separating the vapor phase from the liquid phase to produce a component-rich stream containing the component and a residual liquid stream containing the substance; and recirculating the residual liquid stream as at least part of the makeup for the sweep stream in the liquid state.