摘要 |
A process and a gas permeation apparatus for separating purified methane from hydrocarbons higher than C1 in a feed gas mixture such as natural gas, naphtha, liquified natural gas (LNG), liquified petroleum gas (LPG), off gas from petrochemical industries and others, comprising at least one gas permeation module (1) with a feed gas inlet, an outlet for a gas stream (4) containing purified methane, an outlet for a gas stream (3) containing hydrocarbons higher than C1 and a permselective membrane (1') having a permeate side (4') and a retentate side (3'), characterised in that said permselective membrane (1') consists of glassy, amorphous or semi-crystalline polymers having a glass-transition temperature above the operating temperature of the gas permeation apparatus and that said outlet for the gas stream (4) containing purified methane is arranged on the permeate side (4') of said permeselective membrane (1'). |