FIELD: technological processes.
SUBSTANCE: invention relates to a low-temperature fractionation unit for complex gas treatment with lines of raw and prepared natural gas, comprising reducing devices, inlet separator with condensate discharge line and gas discharge line, which is divided into two lines, on the first line there installed are recuperative heat exchanger, second line adjunction, intermediate separator, reducing device and apparatus equipped with a heat and mass exchange section located in its upper part on the outlet line from the upper part of the prepared natural gas apparatus with a reducing device and a recuperative heat exchanger, and heat exchange device is arranged on second line. Besides, the plant includes a fractionation unit with a demethanised condensate supply line equipped with a product discharge line. Plant is characterized by that as said apparatus a fractionating column is installed with middle part equipped with abutment of gas discharge line from second separator, and lower part, equipped with heat-mass exchange section as heat exchange device located on second line, besides, the lower part of the column is connected to the separators by supply lines of hydrocarbon condensates with reducing devices and is equipped with a demethanised condensate supply line to the fractionation unit, which is equipped with input / output lines of part of prepared natural gas as cooling agent.
EFFECT: high output of C2+ hydrocarbons and avoiding use of external sources of low-temperature cold.
1 cl, 1 dwg
