FIELD: liquefaction or curing of gases.
SUBSTANCE: invention relates to liquefaction of a hydrocarbon-rich fraction. Fraction rich with hydrocarbons is pre-cooled and subjected to treatment for water separation and subsequent drying process before liquefaction. Further, the hydrocarbon-rich fraction is liquefied using a mixed refrigerant circuit. Coolant is compressed in at least two steps, then partially condensed and liquid fraction formed at least partially mixed with coolant, which is compressed to intermediate pressure. Partial stream (17) of the liquid fraction serves for preliminary cooling of liquefied fraction (1, 2) rich with hydrocarbons before its supply to the water compartment (D4) with the help of at least one heat exchange system (E4). Pressure of partial flow (17) of liquid fraction is reduced to pressure which is at least 30 kPa (0.3 bar) higher than suction pressure of second or last stage (V2) of the compressor. Only formed liquid fraction (18) is used for preliminary cooling of fraction (1, 2), which is subject to liquefaction, which is rich with hydrocarbons, before its supply to water compartment (D4).
EFFECT: technical result is reduction of load on drying process.
5 cl, 2 dwg
