Abstract: A process for liquefying a natural gas feed stream including cooling a feed gas stream to obtain a liquefied natural gas stream; introducing the liquefied natural gas stream into a deazotization column to produce a liquefied natural gas stream and a nitrogen-enriched vapor stream; at least partially condensing at least part of the nitrogen-enriched vapor stream to produce a two-phase stream; introducing the two-phase stream into a phase-separating vessel to produce a first liquid stream and a first nitrogen-enriched gas stream; introducing at least part of the nitrogen-enriched gas stream into a distillation column thereby producing a second nitrogen-enriched stream containing less than 1 mol % of methane and a second liquid stream containing less than 10 mol % of nitrogen; wherein at least part of the liquefied natural gas stream is used to cool the at least part of the nitrogen-enriched vapor stream in said heat exchanger.

Abstract: A process for the purification of a gas rich in hydrocarbons and comprising at least 10 ppm by volume of hydrocarbons having at least six carbon atoms nitrogen.

Abstract: A process for liquefying a natural gas feed stream including cooling a feed gas stream to obtain a liquefied natural gas stream; introducing the liquefied natural gas stream into a deazotization column to produce a liquefied natural gas stream and a nitrogen-enriched vapor stream; at least partially condensing at least part of the nitrogen-enriched vapor stream to produce a two-phase stream; introducing the two-phase stream into a phase-separating vessel to produce a first liquid stream and a first nitrogen-enriched gas stream; introducing at least part of the nitrogen-enriched gas stream into a distillation column thereby producing a second nitrogen-enriched stream containing less than 1 mol % of methane and a second liquid stream containing less than 10 mol % of nitrogen; wherein at least part of the liquefied natural gas stream is used to cool the at least part of the nitrogen-enriched vapor stream in said heat exchanger.

Abstract: The method includes the introduction of a feed flow into a first flask, the dynamic; expansion of the gaseous flow issuing from the flask in a turbine, then its introduction into a first purification column. It comprises the production at the head of the first column of a purified gas and the recovery at the bottom of the first column of a liquefied bottom gas, which is introduced, after expansion, into a second column for elimination of the C5+ hydrocarbons. The purified head natural gas issuing from the first column is heated in a first heat exchanger by thermal exchange with a feed gas. The method includes the compression of the gaseous head flow of the second column in a compressor before its introduction into a second separator flask.

Abstract: A method for cryogenically separating a natural gas supply stream into a gas containing the most volatile compounds of the supply stream, and a liquid product containing the heaviest compounds at least including the following. Introducing an at least partially condensed stream into an absorption column at an introduction stage in the lower part of said absorption column, thus producing, at the top, a gaseous stream that contains the most volatile compounds and, the bottom, a liquid product.

Abstract: A process for simultaneously producing treated natural gas and a propane-rich stream from a feed gas comprising methane, ethane and hydrocarbons having more than three carbon atoms.

Abstract: A process for the purification of a gas rich in hydrocarbons and comprising at least 10 ppm by volume of hydrocarbons having at least six carbon atoms nitrogen.

Abstract: This method comprises cooling the feed natural gas in a first heat exchanger and introducing the cooled, feed natural gas into a first separation flask. It comprises the dynamic expansion of a turbine supply flow in a first expansion turbine and introducing the expanded flow into a separation column. This method comprises removing, at the head of the separation column, a head flow rich in methane and removing a first recirculation flow from the compressed head flow rich in methane. The method comprises forming at least a second recirculation flow obtained from the head flow rich in methane downstream of the separation column and forming a dynamic expansion flow from the second recirculation flow.

Abstract: A process for the production of a subcooled liquefied natural gas stream from a natural gas feed stream. Passing a first natural gas feed stream through a first heat exchanger for precooling by heat exchange with a first stream of gaseous refrigerant produced in a first refrigeration cycle comprising a first dynamic expansion turbine. Passing the precooled feed stream through a second heat exchanger for liquefying by heat exchange with a second stream of gaseous refrigerant produced in a second refrigeration cycle comprising a second dynamic expansion turbine. Passing the liquefied natural gas stream through a third heat exchanger for subcooling the liquefied gas by heat exchange with a third refrigerant stream produced in a third refrigeration cycle comprising a third dynamic expansion turbine separate from the first turbine and the second turbine.

Abstract: This process includes the cooling of an introduction stream (72) inside an upstream heat exchanger (28). It includes the introduction of the cooled introduction stream (76) into a fractionating column (50) and the tapping at the bottom portion of the column (50) of the denitrided stream of hydrocarbons. It also includes the introduction of a stream (106) rich in nitrogen obtained from the head portion of the column (50) into a separation container (60) and the recovery of the head gaseous stream from the separation container (60) in order to form the stream (20) which is rich in helium. The liquid stream (110) is obtained from the bottom of the first separation container (60) is separated into a liquid nitrogen stream (18) and a first reflux stream (114) which is introduced as reflux into the head of the fractionating column (50).

Abstract: This method comprises cooling the feed natural gas in a first heat exchanger and introducing the cooled, feed natural gas into a first separation flask. It comprises the dynamic expansion of a turbine supply flow in a first expansion turbine and introducing the expanded flow into a separation column. This method comprises removing, at the head of the separation column, a head flow rich in methane and removing a first recirculation flow from the compressed head flow rich in methane. The method comprises forming at least a second recirculation flow obtained from the head flow rich in methane downstream of the separation column and forming a dynamic expansion flow from the second recirculation flow.

Abstract: This method comprises cooling the feed natural gas in a first heat exchanger and introducing the cooled, feed natural gas into a first separation flask. It comprises the dynamic expansion of a turbine supply flow in a first expansion turbine and introducing the expanded flow into a separation column. This method comprises removing, at the head of the separation column, a head flow rich in methane and removing a first recirculation flow from the compressed head flow rich in methane. The method comprises forming at least a second recirculation flow obtained from the head flow rich in methane downstream of the separation column and forming a dynamic expansion flow from the second recirculation flow.

Abstract: This process includes the cooling of an introduction stream (72) inside an upstream heat exchanger (28). It includes the introduction of the cooled introduction stream (76) into a fractionating column (50) and the tapping at the bottom portion of the column (50) of the denitrided stream of hydrocarbons. It also includes the introduction of a stream (106) rich in nitrogen obtained from the head portion of the column (50) into a separation container (60) and the recovery of the head gaseous stream from the separation container (60) in order to form the stream (20) which is rich in helium. The liquid stream (110) is obtained from the bottom of the first separation container (60) is separated into a liquid nitrogen stream (18) and a first reflux stream (114) which is introduced as reflux into the head of the fractionating column (50).

Abstract: This method comprises cooling the feed natural gas in a first heat exchanger and introducing the cooled, feed natural gas into a first separation flask. It comprises the dynamic expansion of a turbine supply flow in a first expansion turbine and introducing the expanded flow into a separation column. This method comprises removing, at the head of the separation column, a head flow rich in methane and removing a first recirculation flow from the compressed head flow rich in methane. The method comprises forming at least a second recirculation flow obtained from the head flow rich in methane downstream of the separation column and forming a dynamic expansion flow from the second recirculation flow.

Abstract: The method includes the introduction of a feed flow into a first flask, the dynamic expansion of the gaseous flow issuing from the flask in a turbine, then its introduction into a first purification column. It comprises the production at the head of the first column of a purified gas and the recovery at the bottom of the first column of a liquefied bottom gas, which is introduced, after expansion, into a second column for elimination of the C5+ hydrocarbons. The purified head natural gas issuing from the first column is heated in a first heat exchanger by thermal exchange with a feed gas. The method includes the compression of the gaseous head flow of the second column in a compressor before its introduction into a second separator flask.

Abstract: A process for the production of a subcooled liquefied natural gas stream from a natural gas feed stream. Passing a first natural gas feed stream through a first heat exchanger for precooling by heat exchange with a first stream of gaseous refrigerant produced in a first refrigeration cycle comprising a first dynamic expansion turbine. Passing the precooled feed stream through a second heat exchanger for liquefying by heat exchange with a second stream of gaseous refrigerant produced in a second refrigeration cycle comprising a second dynamic expansion turbine. Passing the liquefied natural gas stream through a third heat exchanger for subcooling the liquefied gas by heat exchange with a third refrigerant stream produced in a third refrigeration cycle comprising a third dynamic expansion turbine separate from the first turbine and the second turbine.

Abstract: In this method, the LNG stream is cooled using a refrigerating fluid in a first heat-exchanger. The refrigerating fluid is subjected to a second semi-open refrigeration cycle which is independent of the first cycle. The method comprises a step for introducing the stream of sub-cooled LNG into a distillation column and a step for recovering a stream of gas at the top of the column. The second refrigeration cycle comprises a step for forming a stream of refrigerating fluid from a portion of the top stream of gas, a step for compressing the stream of refrigerating fluid to a high pressure, then a step for expanding a portion of the stream of compressed refrigerating fluid in order to form a substantially liquid sub-cooling stream. The substantially liquid stream is evaporated in the first heat-exchanger.

Abstract: In this process, the LNG stream is sub-cooled with a refrigerating fluid in a first heat exchanger. This refrigerating fluid undergoes a closed second refrigeration cycle which is independent of the first cycle. The closed cycle comprises a phase of heating the refrigerating fluid in a second heat exchanger, and a phase of compressing the refrigerating fluid in a compression apparatus to a pressure greater than its critical pressure. It further comprises a phase of cooling the refrigerating fluid originating from the compression apparatus in the second heat exchanger and a phase of dynamically expanding of a proportion of the refrigerating fluid issuing from the second heat exchanger in a turbine. The refrigerating fluid is formed by a mixture of nitrogen-containing fluids.

Abstract: This method comprises the cooling of the initial natural gas and its introduction into a column for recovering C2+ hydrocarbons. It comprises the recovery of the top stream from the column to form the treated natural gas, and the recovery of the bottom stream from the column for introducing it at a feed level of a fractionating column equipped with a top condenser. The column produces the said C3+ hydrocarbons at the bottom. The method comprises the recovery of the ethane rich stream from an intermediate level of the column located above the said feed level and the production of a secondary reflux stream from the said top condenser refluxed to the top of the recovery column.

Abstract: This process includes the following steps: (a) the feed natural gas (101) is introduced into a first distillation column (31) which produces, as top product, a pretreated natural gas (111), which pretreated natural gas (111) no longer contains practically any C6+ hydrocarbons; (b) the pretreated natural gas (111) is introduced into an NGL recovery unit (19) comprising at least a second distillation column (49), so as to produce, on the one hand, as column top product, a purified natural gas (151) and, on the other hand, an NGL cut (15); and (c) the said liquefiable natural gas (161) is formed from the purified natural gas (151) resulting from step (b).