High-pressure separation of a multi-component gas

A method of separating one or more components from a multi-component gas stream comprising at least one non-acid gas component and at least one acid gas component, the method comprising:

• (a) pressurizing the multi-component gas containing an acid gas composition greater than 20 mole percent and which has a compressibility factor less than 0.8 to create a second stream at a higher pressure;
• (b) separating the second stream in one or more separation stages into at least two streams, a third stream depleted in at least one acid gas component compared to the second stream and a fourth stream enriched in at least one acid gas component compared to the second stream;
• the pressure of the third stream being at a pressure greater than the pressure of the initial multi-component gas stream;
• the pressure of the fourth stream being at a pressure which is less than that of the initial multi-component gas stream;
• and
• (c) pressurizing the fourth stream to a pressure that is higher than that of the initial multi-component gas stream.

A method of separating one or more components from a multi-component gas stream comprising a non-acid gas component and an acid gas component, the method comprising:

• (a) providing the multi-component gas stream at a pressure below 1,200 psai (82.8 bar) or at a temperature below 80° F. (26.7° C.), the concentration of the acid gas component being at least 20 mole percent;
• (b) increasing the fugacity of the acid gas component in the feed stream by at least one of the acts of increasing the temperature of the feed stream to above 80° F. (26.7° C.) or increasing the pressure of the feed stream to above 82.8 bar such that the stream has a temperature above 80° F. (26.7° C.) and a pressure above 82.8 bar;
• and
• (c) passing the multi-component gas stream to a membrane system that selectively separates the acid gas component from the multi-component gas stream as permeate stream, said permeate stream having a pressure at least 20% of the pressure of the feed pressure.