摘要:
The invention concerns a method and an installation for separating a gas mixture and gases obtained by said installation. The invention concerns a method and an installation for cryogenic separation of constituents of a natural gas under pressure (14) with a first phase separator (B1) whereof the constituents of each of the phases are separated in a distillation column (C1). Part of the gas fraction (5) derived from the head of the column (C1) is recycled at the last stage thereof. The method further comprises diverting (9) part of a first head fraction (3) derived from the first phase separator. Additionally, the method comprises separating a first base fraction (4) derived from the first separator, in a second separator (B2). The invention also relates to other embodiments.
摘要:
The invention concerns a method which consists in subcooling a LNG stream (11) with a coolant (41) in a first heat exchanger (19). Said coolant (41) is subjected to a closed refrigerating cycle (21). The closed cycle (21) comprises a phase for heating the coolant (42) in a second heat exchanger (23), and a phase for compressing the coolant (43) in a compression apparatus (25) up to a pressure higher than its critical pressure. It further includes a phase for cooling the coolant (45) from the compression apparatus (25) in the second heat exchanger (23) and a phase of dynamic expansion of part (47) of the refrigerating fluid derived from the second heat exchanger (23) in a turbine (31). The coolant (41) comprises a mixture of nitrogen and methane.
摘要:
The invention concerns a method comprising cooling the initial natural gas (13) and introducing same into a C2+ hydrocarbon recovery column (35). It comprises recovering the overhead stream (131) of the column (35) to form the treated natural gas (15), and recovering the bottoms stream (171) of the column (35) to introduce same at a supply level (P1) of the fractionating column (61) provided with an overhead condenser (63). The column (61) produces in the bottoms said C3+ hydrocarbon cut (17). The method comprises recovering the ethane-rich stream (19) from the intermediate level (P2) of the column (61), located above said supply level (P1) and the production of a secondary reflux stream (191) from said overhead condenser (63) introduced in reflux into the recovery column (35).
摘要:
The method comprises the following steps:(a) introduction of the feed natural gas (101) into a first distillation column (31) which gives a pre-treated natural gas (111) as top product, said pre-treated natural gas (111) being practically free of hydrocarbons of C6+, (b) the pre-treated natural gas (111) is introduced into a liquid natural gas recovery unit (19), comprising at least one second distillation column (49), to produce as top product a purified natural gas (151) and a liquid natural gas cut (15) and (c) the natural gas for liquefaction (161) is formed by the purified natural gas (151) from step (b).
摘要:
The invention concerns a method for refrigerating liquefied natural gas under pressure (1), comprising a first step wherein the LNG (1) is cooled, expanded and separated (a) in a first base fraction (4) which is collected, and (b) a first top fraction (3) which is heated, compressed in a compressor (K1) and cooled into a first compressed fraction (5) which is collected; a second compressed fraction (6) is drawn from the fuel gas (5), cooled then mixed with the cooled and expanded LNG (1). The invention is characterised in that it comprises a second step wherein the second compressed fraction (6) is compressed and cooled, and a flux is (8) drawn and cooled, expanded and introduced in the compressor (K1). The invention also describes other embodiments.
摘要:
This method consists of the introduction of a load current (54) in a first tank (22), the dynamic expansion of the gas current (56) emanating from the tank (22) in a turbine (24), then its introduction into a first purification column (26). It comprises the production at the top of the first column (26) of purified gas (70) and the recovery at the bottom of the first column (26) of a liquefied bottom gas (74), which is introduced after expansion into a second column (30) for elimination of C 5 + hydrocarbons. The purified top natural gas (70) from the first column (26) is reheated in a first heat exchanger (20) by heat exchange with a load gas (12). The method comprises the compression of top gas current (86) in second column (30) in a compressor (38) before it is introduced into a second separator tank (40).
摘要:
The invention concerns a method which consists in cooling the LNG stream (11) with a coolant (83) in a first heat exchanger (19). The coolant (83) is subjected to a second semi-open refrigerating cycle (21), independent of the first cycle (15). The method includes a step of introducing the under-cooled LNG stream (59) in a distillation column (49) and a step of recovering a gas stream (69) at the head of the column (49). The second refrigerating cycle (21) includes a step of forming a coolant stream (73) from part of the head gas stream (69), a step of compressing the coolant stream (73) up to a high pressure, then a step of expanding part (81) of the compressed coolant stream (75) to form an essentially liquid under-cooling stream (83). The essentially liquid stream (83) is evaporated in the first heat exchanger (19).
摘要:
The invention concerns a method for fractionating a gas derived from pyrolysis of hydrocarbons (1) to recover C2 and higher hydrocarbons, in particular ethylene and ethane, comprising an operation (70) which consists in compression and drying of the gas (1) by passing it through a series of compressors (3, 10, 17, 24, 36), an operation (80) which consists in gradual cooling and partial liquefaction of the gas derived from the compression and drying operation (70) by successively passing it in a cryogenic exchanger (62), and a distillation operation (90) in a column (64). The invention also concerns the corresponding installation. The invention is characterized in that the cryogenic exchanger (62) is cooled by at least a coolant (400) which consists in liquid natural gas (LNG).