Process for the recovery of liquid natural gas from a stream of gas fuel with high content of hydrogen and carbon dioxide

摘要

In a method for extracting natural gas liquids from a gas stream (16) that has a high content of hydrogen and carbon dioxide, the gas stream (16) is scrubbed, dehydrated, filtered compressed and chilled prior to entering a demethanizer (48) where the overhead residue gas (56) comprising hydrogen, nitrogen and methane is separated from the demethanizer bottoms product (58). This bottoms product (58) is then warmed prior to entering a de-ethanizer (64) where ethane, ethylene, and carbon dioxide are separated from the de-ethanizer bottoms product (66) which comprises the heavier compounds of propylene, propane, butane and pentane. The cold demethanizer residue gas (58) is used to cool the incoming inlet gas stream (16) via an inlet gas cooler (44), and expanded vapour from a high pressure separator (46) is cross-exchanged with the de-ethanizer overhead product stream (52).