Method for recovering a stream of c2+ hydrocarbons in a residual refinery gas and associated facility

Abstract: The invention relates to a method which comprises injecting a residual current (28) into a flash vessel (30) so as to form an overhead gaseous stream (32) and a bottoms liquid stream (34) and injecting the bottoms stream (34) into a distillation column (38). The method includes cooling the overhead stream (32) in a heat exchanger (36) so as to form a cooled overhead stream (58). The method also comprises the extraction of an overhead gaseous stream (72) at the head of the distilling column (38) and the formation of at least one effluent stream (14) using the overhead stream (72) and/or the top stream (80). The separation of the cooled overhead stream (58) comprises the injection of the cooled overhead stream (58) into an absorber (40), and the injection of a methane-rich stream (42) into the absorber (40) so as to place the cooled overhead stream (58) in contact with the methane-rich stream (42).