Abstract: This method comprises a separation of a feed stream (16) into a first fraction (41A) and a second fraction (41B). It comprises injecting the first cooled feed fraction (42) into a first separating flask (22) to produce a light head stream (44). The method comprises expanding a turbine feed fraction (48) resulting from the light head stream (44) in a first turbine (26) up to a first pressure and injecting the first expanded fraction (54) into a distillation column (30). The method comprises expanding the second fraction of the feed stream (41B) in a second turbine (40) up to a second pressure substantially equal to the first pressure. The second expanded fraction (91A) from the second dynamic expansion turbine (40) is used to form a cooled reflux stream (91B) injected into the column (30).

Abstract: This method comprises a separation of a feed stream (16) into a first fraction (41A) and a second fraction (41B). It comprises injecting the first cooled feed fraction (42) into a first separating flask (22) to produce a light head stream (44). The method comprises expanding a turbine feed fraction (48) resulting from the light head stream (44) in a first turbine (26) up to a first pressure and injecting the first expanded fraction (54) into a distillation column (30). The method comprises expanding the second fraction of the feed stream (41B) in a second turbine (40) up to a second pressure substantially equal to the first pressure. The second expanded fraction (91A) from the second dynamic expansion turbine (40) is used to form a cooled reflux stream (91B) injected into the column (30).

Abstract: This method envisions cooling the supply flow in a first heat exchanger, separation in a first separation flask in order to produce a light upper flow and a heavy lower flow and dividing the light upper flow into a supply fraction of a dynamic pressure reduction turbine and a supply fraction of a first distillation column. A cooled reflux flow is formed from an effluent from a dynamic pressure reduction turbine, the portion of the effluent being cooled and at least partially liquefied in a heat exchanger. The cooled reflux flow is introduced from the heat exchanger into the first distillation column.

Abstract: The method according to the invention comprises the separation of a feed stream (16) into a first fraction (60) and a second fraction (62) and the injection of at least part of the second fraction (62) into a second dynamic expansion turbine (46) to form a second expanded fraction (80). It comprises the cooling of the second expanded fraction (80) through heat exchange with at least part of the first headstream (84) coming from a first column (28) and the formation of a second feed stream (82) of the first column (28) from the second cooled expanded fraction.

Abstract: This method envisions cooling the supply flow in a first heat exchanger, separation in a first separation flask in order to produce a light upper flow and a heavy lower flow and dividing the light upper flow into a supply fraction of a dynamic pressure reduction turbine and a supply fraction of a first distillation column. A cooled reflux flow is formed from an effluent from a dynamic pressure reduction turbine, the portion of the effluent being cooled and at least partially liquefied in a heat exchanger. The cooled reflux flow is introduced from the heat exchanger into the first distillation column.

Abstract: This method comprises cooling the supply flow in a first heat exchanger, separation in a first separation flask in order to produce a light upper flow and a heavy lower flow and dividing the light upper flow into a supply fraction of a dynamic pressure reduction turbine and a supply fraction of a first distillation column. The method comprises forming a cooled reflux flow from an effluent from a dynamic pressure reduction turbine, the portion of the effluent being cooled and at least partially liquefied in a heat exchanger. It comprises introducing the cooled reflux flow from the heat exchanger into the first distillation column.

Abstract: This method envisions cooling the supply flow in a first heat exchanger, separation in a first separation flask in order to produce a light upper flow and a heavy lower flow and dividing the light upper flow into a supply fraction of a dynamic pressure reduction turbine and a supply fraction of a first distillation column. A cooled reflux flow is formed from an effluent from a dynamic pressure reduction turbine, the portion of the effluent being cooled and at least partially liquefied in a heat exchanger. The cooled reflux flow is introduced from the heat exchanger into the first distillation column.

Abstract: This method comprises a separation of a feed stream (16) into a first fraction (41A) and a second fraction (41B). It comprises injecting the first cooled feed fraction (42) into a first separating flask (22) to produce a light head stream (44). The method comprises expanding a turbine feed fraction (48) resulting from the light head stream (44) in a first turbine (26) up to a first pressure and injecting the first expanded fraction (54) into a distillation column (30). The method comprises expanding the second fraction of the feed stream (41B) in a second turbine (40) up to a second pressure substantially equal to the first pressure. The second expanded fraction (91A) from the second dynamic expansion turbine (40) is used to form a cooled reflux stream (91B) injected into the column (30).

Abstract: The method according to the invention comprises the separation of a feed stream (16) into a first fraction (60) and a second fraction (62) and the injection of at least part of the second fraction (62) into a second dynamic expansion turbine (46) to form a second expanded fraction (80). It comprises the cooling of the second expanded fraction (80) through heat exchange with at least part of the first headstream (84) coming from a first column (28) and the formation of a second feed stream (82) of the first column (28) from the second cooled expanded fraction.

Abstract: This method comprises cooling the supply flow in a first heat exchanger, separation in a first separation flask in order to produce a light upper flow and a heavy lower flow and dividing the light upper flow into a supply fraction of a dynamic pressure reduction turbine and a supply fraction of a first distillation column. The method comprises forming a cooled reflux flow from an effluent from a dynamic pressure reduction turbine, the portion of the effluent being cooled and at least partially liquefied in a heat exchanger. It comprises introducing the cooled reflux flow from the heat exchanger into the first distillation column.