FIELD: liquefaction, solidification or separation of gases.
SUBSTANCE: invention relates to extraction of liquefied natural gas flow from gas supplied flow using double closed circuits with mixed coolant. Method of liquefying a hydrocarbon-containing gas comprises cooling a feed stream in a first cooling system by indirect heat exchange with a first mixed coolant to form a first cooled fed stream and cooling the first cooled fed stream in the second cooling system by indirect heat exchange with the second mixed coolant to form a second cooled fed stream. Further, at least a portion of the first or second cooled fed stream is expanded in the turboexpander, is separated in a separator to form a vapour head fraction and a liquid bottom fraction, and at least a portion of the steam head fraction is compressed in a compressor driven by a turboexpander. If the first cooled fed stream is expanded, the compressed vapour fraction is cooled in the first cooling system. If the second cooled fed stream is expanded, at least a portion of the compressed vapour fraction is cooled in the second cooling system.
EFFECT: technical result is reduction of energy consumption.
16 cl, 7 dwg
