process and installation for the production of a liquid nitrogen stream, a nitrogen gas stream, a helium-rich gas stream and a denitrogenated hydrocarbon stream from a charge stream containing hydrocarbons, nitrogen and helium

摘要

process and installation for the production of a liquid nitrogen stream, a nitrogen gas stream, a helium-rich gas stream and a denitrogenated hydrocarbon stream from a charge stream containing hydrocarbons, nitrogen and helium. cooling of a chain (72) of introduction into an upstream heat exchanger (28). it comprises introducing the cooled introduction stream (76) into a fractionation column (50) and collecting, at the bottom of the column (50), the denitrated hydrocarbon stream. it comprises introducing a nitrogen-rich stream (106) from the top of the column (50) into a separating flask (60) and recovering the gaseous top stream from the separating flask (60) to form the helium-rich stream ( 20). the liquid stream (110) from the base of the first separator flask (60) is separated into a stream (18) of liquid nitrogen and a first reflux stream (114) introduced, in reflux, at the top of the fractionation column (50).