FIELD: chemistry.
SUBSTANCE: invention relates to low-temperature separation plants and can be used in gas industry for extraction of hydrocarbons C2+ from natural gas. Disclosed is an apparatus which includes, in embodiment 1, an adsorption drying unit, an evaporator, a compressor, a condenser and a reducing device of the external cooling circuit, a recovery heat exchanger, first and second expanders, a dephlegmator and a demethanizer. Alternative embodiment 2 instead of external cooling circuit includes compressor, refrigerator and third expander. In operation of embodiment 1, high-pressure gas is dried, cooled in parallel in evaporator and recuperative heat exchanger, reduced by first expander and subjected to refluxing by cooling the low-pressure gas fed from separator, which is then heated in recuperative heat exchanger, mixed with regeneration gas and discharged from plant. During circulation, the coolant after heating in the evaporator is compressed with a compressor driven by expanders, cooled in a condenser and reduced. Gas produced in dephlegmator is reduced in the second expander, mixed with methane-containing gas from demethanizer and used as low-pressure gas. From the bottom of the reflux condenser, the reflux is sent to a demethanizer, from which hydrocarbons C2+ and methane-containing gas are removed.
EFFECT: invention increases output of hydrocarbons C2+.
2 cl, 2 dwg
