WO2013087571A2 - Procédé et appareil pour retirer de l'azote d'une composition d'hydrocarbures cryogéniques - Google Patents

Procédé et appareil pour retirer de l'azote d'une composition d'hydrocarbures cryogéniques Download PDF

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Publication number
WO2013087571A2
WO2013087571A2 PCT/EP2012/074959 EP2012074959W WO2013087571A2 WO 2013087571 A2 WO2013087571 A2 WO 2013087571A2 EP 2012074959 W EP2012074959 W EP 2012074959W WO 2013087571 A2 WO2013087571 A2 WO 2013087571A2
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WIPO (PCT)
Prior art keywords
vapour
nitrogen
stream
stripping
fraction
Prior art date
Application number
PCT/EP2012/074959
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English (en)
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WO2013087571A3 (fr
Inventor
Alexandre M.C.R. SANTOS
Original Assignee
Shell Internationale Research Maatschappij B.V.
Shell Oil Company
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shell Internationale Research Maatschappij B.V., Shell Oil Company filed Critical Shell Internationale Research Maatschappij B.V.
Priority to CN201280061162.5A priority Critical patent/CN104011489B/zh
Priority to CA2858155A priority patent/CA2858155C/fr
Priority to RU2014128666A priority patent/RU2607708C2/ru
Priority to AU2012354774A priority patent/AU2012354774B2/en
Priority to US14/364,262 priority patent/US20140345319A1/en
Priority to MYPI2014701217A priority patent/MY185531A/en
Publication of WO2013087571A2 publication Critical patent/WO2013087571A2/fr
Publication of WO2013087571A3 publication Critical patent/WO2013087571A3/fr

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/0204—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the feed stream
    • F25J3/0209—Natural gas or substitute natural gas
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
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    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/08—Separating gaseous impurities from gases or gaseous mixtures or from liquefied gases or liquefied gaseous mixtures
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    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
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    • F25J1/0002—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the fluid to be liquefied
    • F25J1/0022—Hydrocarbons, e.g. natural gas
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    • F25J1/0032—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the kind of cold generation within the liquefaction unit for compensating heat leaks and liquid production using the feed stream itself or separated fractions from it, i.e. "internal refrigeration"
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    • F25J2245/02—Recycle of a stream in general, e.g. a by-pass stream
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2245/00—Processes or apparatus involving steps for recycling of process streams
    • F25J2245/90—Processes or apparatus involving steps for recycling of process streams the recycled stream being boil-off gas from storage
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2280/00—Control of the process or apparatus
    • F25J2280/02—Control in general, load changes, different modes ("runs"), measurements

Definitions

  • the present invention relates to a method and
  • Liquefied natural gas forms an economically important example of such a cryogenic hydrocarbon
  • Natural gas is a useful fuel source, as well as a source of various hydrocarbon compounds. It is often desirable to liquefy natural gas in a liquefied natural gas plant at or near the source of a natural gas stream for a number of reasons. As an example, natural gas can be stored and transported over long distances more readily as a liquid than in gaseous form because it occupies a smaller volume and does not need to be stored at high pressure.
  • WO 2011/009832 describes a method for treating a multi-phase hydrocarbon stream produced from natural gas, wherein lower boiling point components, such as nitrogen, are separated from the multi-phase hydrocarbon stream, to produce a liquefied natural gas stream with a lower content of such lower boiling point components. It employs two subsequent gas/liquid separators operating at different pressures.
  • the multi-phase hydrocarbon stream is fed into the first gas/liquid separator at a first pressure.
  • the bottom stream of the first gas/liquid separator is passed to the second gas/liquid separator, which provides vapour at a second pressure that is lower than the first pressure.
  • the vapour is compressed in an overhead stream compressor, and returned to the first gas/liquid separator as a stripping vapour stream.
  • 2011/009832 describes an embodiment wherein the first gas/liquid separator is provided in the form of a column having two zones with contact enhancing means, e.g.
  • the reflux condenser is cooled by a slip stream of the same stream as from which the multi-phase hydrocarbon stream is prepared.
  • a low pressure fuel gas stream is prepared from the overhead vapour stream discharged from the column, which is passed to a
  • a drawback of the method and apparatus as described in WO 2011/009832 is that the heating value available in the fuel gas may not match with the demand of heating value .
  • the present invention provides a of removing nitrogen from a cryogenic hydrocarbon composition comprising a nitrogen- and methane-containing liquid phase, the method comprising :
  • the present invention provides an apparatus for removing nitrogen from a cryogenic hydrocarbon composition comprising a nitrogen- and methane-containing liquid phase, the apparatus
  • cryogenic feed line for providing a cryogenic hydrocarbon composition comprising nitrogen and a methane-containing liquid phase at an initial pressure
  • nitrogen stripper column in fluid communication with the cryogenic feed line, said nitrogen stripper column comprising at least one internal rectifying section and at least one internal stripping section positioned within the nitrogen stripper column
  • an intermediate depressurizer fluidly connected to the nitrogen stripper column arranged to receive a nitrogen-stripped liquid from a sump space of the nitrogen stripper column gravitationally below the stripping section and to depressurize the nitrogen- stripped liquid, said intermediate depressurizer located on an interface between a stripping pressure side comprising the nitrogen stripper column and a flash pressure side;
  • liquid hydrocarbon product line arranged on the flash pressure side to discharge a liquid hydrocarbon product stream produced from the nitrogen-stripped liquid
  • process vapour line arranged on the flash pressure side to receive a process vapour produced from the nitrogen-stripped liquid; - a process compressor arranged in the process vapour line arranged to receive the process vapour and compress the process vapour to provide a compressed vapour at a process compressor discharge outlet of the process compressor, said process compressor being on said
  • a stripping vapour line in fluid communication with the nitrogen stripper column at a level gravitationally below the stripping section and arranged to receive at least a stripping portion of said compressed vapour from the process compressor;
  • an overhead condenser arranged to bring an overhead vapour obtained from an overhead part of the nitrogen stripper column above the rectifying section in indirect heat exchange contact with an auxiliary refrigerant stream thereby obtaining a partially condensed
  • a discharge line arranged to discharge the vapour fraction having a heating value
  • a reflux system arranged to allow at least a reflux portion of the condensed fraction into the nitrogen stripper column at a level above the said rectifying section;
  • a cooling duty controller arranged to adjust the cooling duty to regulate the heating value of the vapour fraction being discharged.
  • FIG. 1 schematically represents a process flow scheme representing a method and apparatus incorporating an embodiment of the invention.
  • Fig. 2 schematically represents a process flow scheme representing a method and apparatus incorporating another embodiment of the invention.
  • the present description concerns removal of nitrogen from a cryogenic hydrocarbon composition comprising a nitrogen- and methane-containing liquid phase.
  • a least a first portion of the cryogenic hydrocarbon composition is fed to a nitrogen stripper column as a first nitrogen stripper feed stream.
  • the nitrogen stripper column operates at a stripping pressure.
  • a stripping vapour is passed into the nitrogen stripper column, comprising at least a stripping portion of a compressed process vapour that has been produced from the nitrogen-stripped liquid which has been depressurized after drawing it from the nitrogen stripper column.
  • Reflux is generated involving partially condensing overhead vapour of the nitrogen stripper column by passing heat from the overhead vapour to an auxiliary refrigerant stream at a cooling duty.
  • An off gas consisting of a, non-condensed, vapour fraction from the overhead vapour is discharged.
  • the cooling duty is adjusted to control a heating value of the vapour fraction being discharged.
  • the relative amount of methane in the off gas can be regulated.
  • the heating value of the discharged vapour fraction can be regulated to match with a specific demand of heating power. This renders the off gas suitable for use as fuel gas stream, even in
  • the heating value may be regulated to match with an actual demand of heating power by the combustion device.
  • the off gas is consumed at a fuel gas pressure not higher than the stripping pressure.
  • any applied compression has an added associated benefit, such as adding of enthalpy to the process vapour which allows it to be used as stripping vapour.
  • cooling duty reflects the rate at which heat is exchanged in the condenser, which can be expressed in units of power (e.g.
  • the cooling duty is related to the flow rate of the auxiliary refrigerant being subjected to the heat exchanging against the overhead vapour.
  • the heating value being regulated may be selected in accordance with the appropriate circumstances of the intended use of the off gas as fuel gas.
  • the heating value may be determined in accordance with DIN 51857 standards.
  • the heating value being regulated may be proportional to the lower heating value (LHV; sometimes referred to as net calorific value) , which may be defined as the amount of heat released by combusting a specified quantity (initially at 25°C) and returning the temperature of the combustion products to 150°C. This assumes the latent heat of vaporization of water in the reaction products is not recovered .
  • LHV lower heating value
  • the cooling duty is automatically
  • the presently proposed method and apparatus are most beneficial when the raw liquefied product, or the cryogenic hydrocarbon composition, contains from 1.5 mol%, preferably from 1.8 mol%, up to 5 mol% of nitrogen.
  • Existing alternative approaches may also work adequately when the nitrogen content is below about 1.8 mol% and/or below about 1.5 mol%.
  • the proposed method and apparatus allow for re- condensation of vaporous methane that has previously formed part of the raw liquefied product, to the extent that it is in excess of a target amount of methane in the discharged vapour fraction, by adding any such vaporous methane containing stream to the (compressed) process vapour stream.
  • the vaporous methane can find its way to the heat exchanging with the auxiliary refrigerant by which it is selectively condensed out of the overhead vapour from the nitrogen stripper column while allowing the majority of the nitrogen to be discharged with the off gas.
  • Vaporous methane that has previously formed part of the raw liquefied product can be formed in an LNG
  • methane containing vapour is formed from the (raw) liquefied product in the form of:
  • loading mode operation The operation mode of an LNG plant while there are ongoing transporter loading operations (typically ship loading operations) is known as loading mode operation.
  • boil-off gas is
  • the proposed solution may facilitate the handling of these vapours both during holding mode and loading mode operations. It combines the removal of nitrogen from the cryogenic hydrocarbon composition with re-condensation of excess vaporous methane. This forms an elegant solution in situations where little plant fuel is demanded, such as could be the case in an electrically driven plant using electric power from an external power grid.
  • the proposed method and apparatus are specifically suitable for application in combination with a
  • hydrocarbon liquefaction system such as a natural gas liquefaction system, in order to remove nitrogen from the raw liquefied product. It has been found that even when the raw liquefied product - or the cryogenic hydrocarbon composition - contains a fairly high amount of from 1 mol% (or from about 1 mol%) up to 5 mol% (or up to about 5 mol%) of nitrogen, the resulting liquid hydrocarbon product can meet a nitrogen content within a
  • FIG. 1 illustrates an apparatus comprising an embodiment of the invention.
  • a cryogenic feed line 8 is in fluid communication with a nitrogen stripper column 20, via a first inlet system 21.
  • a first feed line 10 connects the cryogenic feed line 8 with the first inlet system 21 of the nitrogen stripper column 20, optionally via an initial stream splitter 9 arranged between the cryogenic feed line 8 and the first feed line 10.
  • a liquefaction system 100 may be provided upstream of the cryogenic feed line 8.
  • the liquefaction system 100 functions as a source of a cryogenic hydrocarbon
  • the liquefaction system 100 is in fluid communication with the cryogenic feed line 8 via a main depressurizing system 5, which communicates with the liquefaction system 100 via a raw liquefied product line 1.
  • the main depressurizing system 5 consists of a dynamic unit, such as an expander turbine 6, and a static unit, such as a Joule Thomson valve 6, but other variants are possible.
  • any compressor forming part of the hydrocarbon liquefaction process in the liquefaction system is driven by one or more electric motors, without being mechanically driven by any steam- and/or gas turbine.
  • Such compressor may be driven exclusively by one or more electric motors.
  • the nitrogen stripper column 20 comprises an internal rectifying section 22 and an internal stripping section
  • the internal stripping section 24 is positioned within the nitrogen stripper column 20, gravitationally lower than the rectifying section 22.
  • the first inlet system 21 is provided gravitationally between the
  • An overhead vapour discharge line 30 communicates with the nitrogen stripper column 20 via an overhead part 26 formed by a space within the nitrogen stripper column 20 gravitationally above the rectifying section 22.
  • a nitrogen-stripped liquid discharge line 40 communicates with the nitrogen stripper column 20 via a sump space 28 within the nitrogen stripper column 20 gravitationally below the stripping section 24.
  • Each of the internal rectifying section 22 and the internal stripping section 24 may comprise vapour/liquid contact-enhancing means to enhance component separation and nitrogen rejection.
  • Such contact-enhancing means may be provided in the form of trays and/or packing, in the form of either structured or non-structured packing.
  • An intermediate depressurizer 45 is arranged in the nitrogen-stripped liquid discharge line 40, and thereby fluidly connected to the nitrogen stripper column 20.
  • the intermediate depressurizer 45 is functionally coupled to a level controller LC, which cooperates with the sump space 28 of the nitrogen stripper column 20.
  • the intermediate depressurizer 45 is located on an interface between a stripping pressure side comprising the nitrogen stripper column 20, and a flash pressure side.
  • the flash pressure side comprises a liquid
  • the flash pressure side furthermore comprises a cryogenic storage tank 210 connected to the liquid hydrocarbon product line 90 for storing the liquid hydrocarbon product stream, an optional boil-off gas supply line 230, and an optional end flash separator 50.
  • end flash separator 50 may be configured in fluid communication with the nitrogen stripper column 20 via the intermediate depressurizer 45 and the nitrogen-stripped liquid discharge line 40.
  • the end flash separator 50 may then be connected to the cryogenic storage tank 210 via the liquid hydrocarbon product line 90.
  • a cryogenic pump 95 may be present in the liquid hydrocarbon product line 90 to assist the transport of the liquid hydrocarbon product to the cryogenic storage tank 210.
  • the process vapour line 60 as shown in the
  • Fig. 1 may be connected to the optional end flash separator 50 via a flash vapour line 64 and flash vapour flow control valve 65, as well as to the cryogenic storage tank 210 via the optional boil-off gas supply line 230.
  • An advantage of the latter connection is that it allows for re-condensing of at least part of the boil-off gas from the cryogenic storage tank 210 by means of an overhead condenser 35 which will be further discussed herein below.
  • boil-gas In a typical LNG plant the generation of boil-gas can exceed the flow rate of flash vapour by multiple times, particularly during operating the plant in so-called loading mode, and hence it is an important benefit to not only re-condense the flash vapour but to re-condense boil-off gas as well if there is not enough on-site demand for heating power to use all of the methane contained in the boil-off gas.
  • stripping pressure side and the flash pressure side is a process compressor 260.
  • the process is a process compressor 260.
  • the compressor 260 is driven by an electric motor.
  • the process compressor 260 is arranged in the process vapour line 60 to receive the process vapour and to compress the process vapour.
  • a compressed vapour discharge line 70 is fluidly connected with a process compressor discharge outlet 261 of the process compressor 260.
  • the process compressor 260 is provided with anti-surge control and a recycle cooler which is used when the process compressor is on recycle and during start-up (not shown in the drawing) .
  • a stripping vapour line 71 is in fluid communication with the nitrogen stripper column 20 via a second inlet system 23 configured at a level gravitationally below the stripping section 24 and preferably above the sump space
  • the stripping vapour line 71 is connected to the compressed vapour discharge line 70 via an optional bypass splitter 79.
  • a stripping vapour valve 75 is provided in the stripping vapour line 71.
  • an external stripping vapour supply line is provided.
  • the optional external stripping vapour supply line 74 connects to the
  • stripping vapour flow control valve 73 is provided in the optional external stripping vapour supply line 74.
  • the optional external stripping vapour supply line 74 is suitably connected to a hydrocarbon vapour line in, or upstream of, the liquefaction system
  • An overhead condenser 35 is arranged in the overhead vapour discharge line 30. Inside the overhead condenser 35 the overhead vapour can pass in indirect heat exchange contact with an auxiliary refrigerant stream 132, whereby heat passes from the overhead vapour to the auxiliary refrigerant stream at a cooling duty.
  • An auxiliary refrigerant stream flow control valve 135 is provided in the auxiliary refrigerant line 132.
  • a cooling duty controller 34 controls the cooling duty, being the rate at which heat passes from the overhead vapour to the auxiliary refrigerant stream, in response to an indicator of heating value of the off gas relative to a demand for heating power.
  • the cooling duty controller 34 is embodied in the form of a pressure controller PC and the auxiliary refrigerant stream flow control valve 135, which are functionally coupled to each other.
  • an overhead separator 33 is arranged on a downstream side of the overhead vapour discharge line 30.
  • the overhead vapour discharge line 30 discharges into the overhead separator 33.
  • the overhead separator 33 is arranged to separate any, non-condensed, vapour fraction from any condensed fraction of the overhead vapour.
  • a vapour fraction discharge line 80 is arranged to discharge the vapour fraction.
  • a reflux system is arranged to allow at least a reflux portion 36 of the condensed fraction into the nitrogen stripper column 20 at a level above the
  • the reflux system comprises a condensed fraction
  • the optional condensed fraction splitter 39 fluidly connects the condensed fraction discharge line 37 with the nitrogen stripper column 20, via a reflux portion line 36 and a reflux inlet system 25, and with an optional liquid recycle line 13.
  • the liquid recycle line 13 is in liquid communication with the liquid hydrocarbon product line
  • Liquid communication means that the liquid recycle line 13 is connected to any suitable location from where at least a part of a liquid recycle portion can flow into the liquid hydrocarbon product line 90 while staying in the liquid phase.
  • the liquid recycle line 13 may for instance be connected directly to one or more
  • the nitrogen stripper column 20 selected from the group consisting of: the nitrogen stripper column 20, the cryogenic feed line 8, the first feed line 10, an optional second feed line 11 which will be described below, the nitrogen-stripped liquid
  • a recycle valve 14 is configured in the optional liquid recycle line 13.
  • An optional reflux flow valve 32 functionally controlled by a reflux flow controller may preferably be provided in the reflux portion line 36.
  • the liquid recycle line 13 is in liquid communication with the liquid hydrocarbon product line 90, preferably via a recycle path that does not pass through the
  • the optional bypass splitter 79 is in fluid
  • vapour bypass line 76 may be provided between the optional bypass splitter 79 and the overhead vapour discharge line 30.
  • a vapour bypass control valve 77 is preferably provided in the vapour bypass line 76.
  • the vapour bypass line 76 suitably extends along a bypass path between the bypass splitter 79 the overhead vapour discharge line 30 on an upstream side of the overhead condenser 35.
  • the bypass path extends between the bypass splitter 79 and the overhead vapour discharge line 30 and/or the vapour fraction discharge line 80.
  • the bypass path does not pass through the internal stripping section 24 in the nitrogen stripper column 20. This way it can be avoided that the non-stripping portion passes through the internal stripping section 24, which helps to avoid disturbing the equilibrium in the nitrogen stripper column 20.
  • cryogenic feed line 8 is also connected to at least one of the group consisting of: the nitrogen-stripped liquid discharge line 40, the liquid hydrocarbon product line 90 and the process vapour line 60.
  • a second feed line 11 is connected at an upstream side thereof to the optional initial splitter 9. This second feed line 11 bypasses the nitrogen stripper column 20.
  • a bypass stream flow control valve 15 is arranged in the second feed line 11. The bypass stream flow control valve is functionally connected to a flow controller FC provided in the first feed line 10. Suitably, the second feed line 11 feeds into the optional end flash separator 50.
  • a benefit of the optional second feed line 11 and the optional initial splitter 9 is that the nitrogen stripper column 20 can be sized smaller than in the case that the cryogenic feed line 8 and the first feed line 10 are directly connected without a splitter such that all of the cryogenic hydrocarbon composition is let into the nitrogen stripper column 20 via the first inlet system 21.
  • a combustion device 220 is arranged on a downstream end of the vapour fraction discharge line 80, to receive at least a fuel portion of the vapour fraction in the vapour fraction discharge line 80.
  • the combustion device may comprise multiple combustion units, and/or it may include for example one or more of a furnace, a boiler, an incinerator, a dual fuel diesel engine, or
  • a boiler and a duel fuel diesel engine may be coupled to an electric power generator.
  • a cold recovery heat exchanger 85 may be provided in the vapour fraction discharge line 80, to preserve the cold vested in the vapour fraction 80 by heat exchanging against a cold recovery stream 86 prior to feeding the vapour fraction 80 to any combustion device.
  • the cold recovery stream 86 may comprise or consist of a side stream sourced from the hydrocarbon feed stream in the hydrocarbon feed line 110 of the liquefaction system 100.
  • the resulting cooled side stream may for instance be combined with the
  • the cold recovery stream 86 may comprise or consist of the overhead vapour in the
  • overhead vapour discharge line 30 preferably in the part of the overhead vapour discharge line 30 where through the overhead vapour is passed from the nitrogen stripper column 20 to the overhead condenser 35.
  • the duty required from the auxiliary refrigerant stream 132 in the overhead condenser 35 would be reduced.
  • An optional vapour fraction splitter 89 may be provided in the vapour fraction line 80, allowing
  • vapour recycle line 87 bypasses the nitrogen stripper column 20, and feeds back into at least one of the group consisting of: the liquid hydrocarbon product line 90 and the process vapour line 60.
  • a vapour recycle flow control valve 88 is preferably provided in the vapour recycle line 87.
  • hydrocarbon product stream 90
  • Either one or both of the second feed line 11 and the vapour recycle line 87 may suitably feed into the
  • suitable liquefaction systems can represent any suitable hydrocarbon liquefaction system and/or process, in particular any natural gas liquefaction process producing liquefied natural gas, and the invention is not limited by the specific choice of liquefaction system.
  • suitable liquefaction systems employ single refrigerant cycle processes (usually single mixed refrigerant - SMR - processes, such as PRICO described in the paper "LNG Production on floating platforms” by K R Johnsen and P Christiansen, presented at Gastech 1998 (Dubai), but also possible is a single component refrigerant such as for instance the BHP-cLNG process also described in the afore-mentioned paper by Johnsen and Christiansen) ;
  • C3MR such as described in for instance US Patent 4,404,008, or for instance double mixed
  • refrigerant - DMR - processes of which an example is described in US Patent 6,658,891, or for instance two- cycle processes wherein each refrigerant cycle contains a single component refrigerant); and processes based on three or more compressor trains for three or more
  • cryogenic heat exchanger 180 in this case in the form of a coil wound heat exchanger comprising lower and upper hydrocarbon product tube bundles (181 and 182, respectively), lower and upper LMR tube bundles (183 and 184, respectively) and an HMR tube bundle 185.
  • the lower and upper hydrocarbon product tube bundles 181 and 182 fluidly connect the raw liquefied product line 1 with a hydrocarbon feed line 110.
  • At least one refrigerated hydrocarbon pre-cooling heat exchanger 115 may be provided in the hydrocarbon feed line 110 upstream of the cryogenic heat exchanger 180.
  • a main refrigerant in the form of a mixed
  • refrigerant is provided in a main refrigerant circuit
  • the main refrigerant circuit 101 comprises a spent refrigerant line 150, connecting the cryogenic heat exchanger 180 (in this case a shell side 186 of the cryogenic heat exchanger 180) with a main suction end of a main refrigerant compressor 160, and a compressed refrigerant line 120 connecting a main refrigerant compressor 160 discharge outlet with an MR separator 128.
  • One or more heat exchangers are provided in the compressed refrigerant line 120, including in the present example at least one ambient heat exchanger 124 and at least one refrigerated main refrigerant pre-cooling heat exchanger 125.
  • the MR separator 128 is in fluid
  • the at least one refrigerated hydrocarbon pre-cooling heat exchanger 115 and the at least one refrigerated main refrigerant pre-cooling heat exchanger 125 are
  • pre-cooling refrigerant via lines 127 and 126, respectively.
  • the same pre-cooling refrigerant may be shared from the same pre-cooling refrigerant cycle.
  • the at least one refrigerated refrigerant via lines 127 and 126, respectively.
  • hydrocarbon pre-cooling heat exchanger 115 and the at least one refrigerated main refrigerant pre-cooling heat exchanger 125 may be combined into one pre-cooling heat exchanger unit (not shown) .
  • hydrocarbon feed line 110 either at a point upstream of the at least one refrigerated hydrocarbon pre-cooling heat exchanger 115, downstream of the at least one refrigerated hydrocarbon pre-cooling heat exchanger 115, or (for instance possible if two or more refrigerated hydrocarbon pre-cooling heat exchangers are provided) between two consecutive refrigerated hydrocarbon pre- cooling heat exchangers, to be sourced with a part of the hydrocarbon feed stream from the hydrocarbon feed line
  • the HMR tube bundle 185 is in fluid connection with an HMR line 141 in which an HMR control valve 144 is configured.
  • the HMR line 141 is in fluid communication with the shell side 186 of the cryogenic heat exchanger 180 and, via said shell side 186 and in heat exchanging arrangement with each of one of the lower hydrocarbon product tube bundle 181 and the lower LMR tube bundle 183 and the HMR tube bundle 185, with the spent refrigerant line 150.
  • the LMR tube bundle 184 is in fluid connection with an LMR line 131.
  • a first LMR return line 133 establishes fluid
  • An LMR control valve 134 is configured in the first LMR return line 133.
  • the first LMR return line 133 is in fluid communication with the spent refrigerant line 150, via said shell side 186 and in heat exchanging arrangement with each of one of the upper and lower hydrocarbon product tube bundles 182 and 181, and each one of the LMR tube bundles 183 and
  • FIG. 2 reveals one possible source of the auxiliary refrigerant.
  • the LMR line 131 is split into the
  • auxiliary refrigerant line 132 and the first LMR return line 133.
  • a second LMR return line 138 on an upstream end thereof fluidly connects with the auxiliary
  • the optional liquid recycle line 13 including the optional liquid recycle line 13, the optional external stripping vapour supply line 74, the optional vapour bypass line 76 and the optional vapour recycle line 87 may be provided but have not been
  • the overhead condenser 35, the overhead separator 33 and the reflux system have been embodied in the form of an integrated internal overhead condenser 235 known in the art, which may be configured inside the overhead part 26 of the nitrogen stripper column 20.
  • the optional liquid recycle line 13 can be provided in the case of Figure 2 as well, for instance by providing the optional condensed fraction splitter 39 in the form of a partial liquid draw off tray (not shown) gravitationally between the integrated internal overhead condenser 235 and the rectifying section 22.
  • the apparatus and method for removing nitrogen from a cryogenic hydrocarbon composition comprising a nitrogen- and methane-containing liquid phase may be operated as follows.
  • a cryogenic hydrocarbon composition 8 comprising a nitrogen- and methane-containing liquid phase is
  • the cryogenic hydrocarbon composition 8 may be obtained from natural gas or petroleum reservoirs or coal beds. As an alternative the cryogenic hydrocarbon composition 8 may also be obtained from another source, including as an example a synthetic source such as a Fischer-Tropsch process. Preferably the cryogenic hydrocarbon composition 8 comprises at least 50 mol% methane, more preferably at least 80 mol% methane.
  • the temperature of lower than -130 °C can be achieved by passing a hydrocarbon feed stream 110 through the liquefaction system 100.
  • the hydrocarbon feed stream 110 comprising a hydrocarbon-containing feed vapour may be heat exchanged, for example in the cryogenic heat
  • the desired cryogenic hydrocarbon composition 8 may then be obtained from the raw liquefied stream 1.
  • the main refrigerant stream may be generated by cycling the main refrigerant in the main refrigerant circuit 101, whereby spent refrigerant 150 is compressed in the main refrigerant compressor 160 to form a
  • the light refrigerant fraction 121 is passed via successively the lower LMR bundle 183 and the upper LMR bundle 184 through the cryogenic heat exchanger 180, while the heavy refrigerant fraction 122 is passed via the HMR bundle 185 through the cryogenic heat exchanger
  • hydrocarbon feed stream 110 passes through the cryogenic heat exchanger 180 via successively the lower hydrocarbon bundle 181 and the upper hydrocarbon bundle 182 and is being liquefied and sub-cooled against the same
  • the hydrocarbon feed stream 110 may contain varying amounts of components other than methane and nitrogen, including one or more non- hydrocarbon components other than water, such as CO 2 , Hg, H 2 S and other sulphur compounds; and one or more
  • hydrocarbons heavier than methane such as in particular ethane, propane and butanes, and, possibly lesser amounts of pentanes and aromatic hydrocarbons.
  • Hydrocarbons with a molecular mass of at least that of propane may herein be referred to as C3+ hydrocarbons
  • hydrocarbons with a molecular mass of at least that of ethane may herein be referred to as C2+ hydrocarbons.
  • the hydrocarbon feed stream 110 may have been pre-treated to reduce and/or remove one or more of undesired components such as CO 2 and H 2 S, or have
  • composition of the hydrocarbon feed stream 110 thus varies depending upon the type and location of the gas and the applied pre-treatment ( s ) .
  • the raw liquefied stream 1 may comprise between from
  • 1 mol% to 5 mol% nitrogen be at a raw temperature of between from -165 °C to -120 °C and at a liquefaction pressure of between from 15 bara to 120 bara.
  • the raw temperature may be between from -155 °C to -140 °C.
  • the cooling duty needed in the liquefaction system 100 is lower than when lower temperatures are desired, while the amount of sub- cooling at the pressure of above 15 bara is sufficiently high to avoid excessive production of flash vapours upon depressurizing to between 1 and 2 bara.
  • the cryogenic hydrocarbon composition 8 may be obtained from the raw liquefied stream 1 by main
  • a first nitrogen stripper feed stream 10 is derived from the cryogenic hydrocarbon composition 8, and fed into the nitrogen stripper column 20 at a stripping pressure via the first inlet system 21.
  • the stripping pressure is usually equal to or lower than the initial pressure.
  • the stripping pressure in preferred embodiments is selected in a range of between 2 and 15 bar absolute.
  • the stripping pressure is at least 4 bara, more preferably at least 5 bara, because with a somewhat higher stripping pressure the stripping vapour in stripping vapour line 71 can benefit from some additional enthalpy (in the form of heat of compression) that is added to the process stream 60 in the process compressor 260.
  • the stripping pressure is at most 8 bara, more preferably at most
  • the off gas in the vapour fraction line 80 can readily be used as so-called low pressure fuel stream without a need to further compress.
  • the raw temperature of the raw liquefied stream 1 was -161 °C while the liquefaction pressure was 55 bara.
  • the main depressurization may be effected in two stages: first a dynamic stage using the expansion turbine 6 to reduce the pressure from 55 bara to about 10 bara, followed by a further depressurization in a static stage using the Joule Thomson valve 7 to a pressure of 7 bara.
  • the stripping pressure in this case was assumed to be 6 bara.
  • the first nitrogen stripper feed stream 10 comprises a first portion of the cryogenic hydrocarbon composition 8. It may contain all of the cryogenic hydrocarbon composition 8, but in practice it is preferred to split the cryogenic hydrocarbon composition 8 into the first portion 10 and a second portion 11 having the same composition and phase as the first portion 10, and to divert the second portion, in the form of a bypass feed stream, to for instance an optional end flash separator
  • the stream splitting of the cryogenic hydrocarbon composition into the first and second portions is such that the second portion 11 has the same composition and phase as the first portion 10.
  • the split ratio defined as the flow rate of the second portion relative to the flow rate of the cryogenic hydrocarbon composition in the cryogenic hydrocarbon composition line 8, may be controlled using the bypass stream flow control valve 15.
  • This bypass stream flow control valve 15 may be controlled by the flow controller FC to maintain a predetermined target flow rate of the first nitrogen stripper feed stream 10 into the nitrogen stripper column 20.
  • the flow controller FC will increase the open fraction of the bypass stream flow control valve 15 if there is a surplus flow rate that exceeds the target flow rate, and decrease the open fraction if there is a flow rate deficit compared to the target flow rate.
  • the split ratio may
  • the cryogenic hydrocarbon composition 8 advantageously be selected between 50 % and 95 %.
  • the lower values are typically recommended for higher content of nitrogen in the cryogenic hydrocarbon composition, while higher values are preferred for lower content of nitrogen.
  • the content of nitrogen in the cryogenic hydrocarbon composition 8 was 3.0 mol% whereby the selected split ratio was 75%.
  • An overhead vapour stream 30 is obtained from the overhead part 26 of the nitrogen stripping column 20, above the rectifying section 22.
  • a nitrogen-stripped liquid 40 is drawn from the sump space 28 of the nitrogen stripper column 20.
  • temperature of the nitrogen-stripped liquid 40 is typically higher than that of the first nitrogen stripper feed stream 10. Typically, it is envisaged that the temperature of the nitrogen-stripped liquid 40 is higher than that of the first nitrogen stripper feed stream 10 and between -140 °C and -80 °C, preferably
  • the flash pressure that is lower than the stripping pressure, suitably in a range of between from 1 and 2 bar absolute.
  • the flash pressure suitably in a range of between from 1 and 2 bar absolute.
  • stripping vapour in stripping vapour line 71 can benefit from some additional heat of compression that is added to the process stream 60 in the process compressor 260.
  • the intermediate depressurizer 45 may be controlled by the level controller LC, set to increase the flow rate through the intermediate depressurizer if the level of liquid accumulated in the sump space 28 of the nitrogen stripper column 20 increases above a target level. As a result of the depressurization, the temperature is generally lowered to below -160 °C.
  • hydrocarbon product stream 90 that is produced hereby can typically be kept at an atmospheric pressure in an open insulated cryogenic storage tank.
  • Process vapour 60 is produced as well.
  • the process vapour 60 may comprise flash vapour 64 that is often generated upon the depressurization of the nitrogen- stripped liquid 40 and/or boil-off gas 230 that may be generated as a result of adding of heat to the liquid hydrocarbon product stream 90 whereby a part of the liquid hydrocarbon product stream 90 evaporates to form the boil-off gas.
  • the optional second portion originating from the optional initial stream splitter 9 may also be
  • the optional second portion is passed into the optional end flash separator 50.
  • the optional boil-off gas supply line 230 connects a vapour space in the cryogenic storage tank 210 with the process vapour line 60.
  • the nitrogen-stripped liquid after its depressurization is fed into the optional end flash separator where it is phase separated at a flash
  • the flash separation pressure is equal to or lower than the flash pressure, and suitably lies in the range of between from 1 to 2 bar absolute into the liquid hydrocarbon product stream 90 and the flash vapour 64. In one embodiment the flash separation pressure is envisaged to be 1.05 bara.
  • the process vapour 60 is compressed to at least the stripping pressure, thereby obtaining a compressed vapour stream 70.
  • a stripping vapour stream 71 is obtained from the compressed vapour stream 70, and passed into the nitrogen stripper column 20 via the second inlet system 23. This stripping vapour can percolate upward through the stripping section 23 in contacting counter current with liquids percolating downward through the stripping section 23.
  • an external stripping vapour may selectively be fed into the nitrogen stripper column 20 via the second inlet system 23.
  • major disruption of the nitrogen stripper column 20 may be avoided, for instance, in case the process compressor 260 is not functioning to provide the compressed vapour stream 70 in sufficient amounts .
  • Obtaining of the stripping vapour stream 71 from the compressed vapour stream 70 may involve splitting the compressed vapour stream 70 into the stripping vapour stream 71 and a vapour bypass portion that does not comprise the stripping portion and that can be
  • vapour bypass control valve 77 is controlled by a pressure controller on the compressed vapour line 70, which is set to
  • vapour bypass control valve 77 increases the open fraction of the vapour bypass control valve 77 in response to an increasing pressure in the compressed vapour line 70. It is envisaged that the flow rate of the vapour bypass portion that is allowed to flow through the vapour bypass line 76 into the overhead vapour stream 30 is particularly high during so-called loading mode at which time usually the amount of boil-off gas is much higher than in is usually the case during so- called holding mode. Preferably, the vapour bypass control valve 77 is fully closed during normal operation in holding mode.
  • a partially condensed intermediate stream is formed from an overhead vapour 30 obtained from an overhead part of the nitrogen stripping column 20 above the rectifying section 22. This involves indirectly heat exchanging the overhead vapour 30 against the auxiliary refrigerant stream 132, whereby heat is passed from the overhead vapour 30 to the auxiliary refrigerant stream 132 at a selected cooling duty.
  • the resulting partially condensed intermediate stream comprises a condensed fraction and a vapour fraction.
  • the condensed fraction is separated from the vapour fraction in the overhead separator 33, at a separation pressure that may be lower than the stripping pressure, and preferably lies in a range of between 2 and 15 bar absolute.
  • the vapour fraction is discharged via the vapour fraction discharge line 80.
  • fraction is discharged from the overhead separator 33 into a reflux system, for instance via the condensed fraction discharge line 37.
  • At least a fuel portion of the vapour fraction 80 is passed to the combustion device 220 at a fuel gas pressure that is not higher than the stripping pressure.
  • the fuel gas pressure may be in the range of from 3 to 5 bara, for instance when the combustion device 220 consists of one or more furnaces.
  • the stripping pressure may for instance be in the range of from 5 to 7 bara. This way no compressor is needed for the fuel gas and the fuel gas can flow to the
  • combustion device 220 by pressure control.
  • the cooling duty is automatically adjusted to
  • the controlling can be done in response to the demanded heating power, whereby the partial flow rate of methane is controlled to achieve a heating value that matches the demand.
  • the auxiliary refrigerant stream flow control valve 135 may be controlled by the pressure controller PC to maintain a predetermined target flow rate of auxiliary refrigerant stream 132 through the overhead condenser 35.
  • the actual pressure in the vapour fraction discharge line 80 is causally related to the heating value that is being regulated.
  • the pressure controller PC will be set to decrease the open fraction of the auxiliary refrigerant stream flow control valve 135 when the pressure drops below a pre-determined target level, which is indicative of a higher consumption rate of methane than supply rate in the vapour fraction 80. Conversely, the pressure controller PC will be set to increase the open fraction of the auxiliary refrigerant stream flow control valve 135 when the pressure exceeds the pre-determined target level.
  • the vapour fraction 80 is envisaged to contain between from 50 mol% to 95 mol% of nitrogen, preferably between from 70 mol% to 95 mol% of nitrogen or between from 50 mol% to 90 mol% of nitrogen, more preferably between from 70 mol% to 90 mol% of nitrogen, still more preferably from 75 mol% to 95 mol% of nitrogen, most preferably from 75 mol% to 90 mol% of nitrogen.
  • the condensed fraction 37 is contemplated to contain less than 35 mol% of nitrogen.
  • the condensed fraction is allowed into the nitrogen stripper column 20, starting at a level above the rectifying section 22.
  • the condensed fraction may pass through the optional reflux pump 38 (and/or it may flow under the influence of gravity) .
  • the reflux portion is then obtained from the condensed fraction and charged into the nitrogen stripper column 20 via reflux inlet system 25 and reflux portion line 36.
  • the condensed fraction is separated inside the overhead part of the nitrogen stripper column 20 and therefore already
  • the reflux portion may contain all of the condensed fraction, but optionally, the condensed fraction is split in the optionally provided condensed fraction splitter 39 into a liquid recycle portion which is charged via liquid recycle line 13 into, for instance, the first feed stream
  • the capability of splitting the condensed fraction into the reflux portion 36 and the liquid recycle portion 13 is beneficial to divert any excess condensed fraction around the rectifying section 22 such as not to upset the operation of the rectifying section 22.
  • the recycle valve 14 may suitably be
  • the partially condensing may also involve direct and/or indirect heat exchanging with other streams in other consecutively arranged overhead heat exchangers.
  • the cold recovery heat exchanger 85 may be such an overhead heat exchanger whereby the partially condensing of the overhead stream further comprises indirect heat exchanging against the vapour fraction 80.
  • the auxiliary refrigerant 132 stream preferably has a bubble point under standard conditions at a lower
  • the auxiliary refrigerant may contain between from 5 mol% to
  • the auxiliary refrigerant stream is formed by a slip stream of the main refrigerant stream, more preferably by a slip stream of the light refrigerant fraction. This latter case is illustrated in Figure 2 but may also be applied in the embodiment of Figure 1.
  • Such a slip stream may conveniently be passed back into the main refrigerant circuit via the shell side 186 of the cryogenic heat exchanger 180, where it may still assist in withdrawing heat from the stream in the upper and or lower tube bundles .
  • a contemplated composition of the auxiliary refrigerant contains between 25 mol% and
  • auxiliary refrigerant contains at least 95% of these constituents and/or the total of nitrogen and methane is at least 65 mol%.
  • a composition within these ranges is may be readily available from the main
  • refrigerant circuit if a mixed refrigerant is employed for sub-cooling of the liquefied hydrocarbon stream.
  • the optional vapour recycle line 87 may be
  • vapour recycle control valve 88 selectively employed, suitably by selectively opening the vapour recycle control valve 88, to increase the amount of nitrogen that remains in the liquid hydrocarbon product stream 90. This may be done by drawing a
  • vapourous recycle portion from the vapour fraction depressurising the vaporous recycle portion to the flash pressure and subsequently injecting the vaporous recycle portion into the nitrogen-stripped liquid 40.
  • the remaining part of the vapour fraction 80 that is not passed into the vapour recycle line 87 may form the fuel portion that may be conveyed to the combustion device 220.
  • the target amount of nitrogen dissolved in the liquid hydrocarbon product stream 90 is between 0.5 and 1 mol%, preferably as close to 1.0 mol% as possible yet not exceeding 1.1 mol%.
  • the vapour recycle flow control valve 88 regulates the amount of the vapour fraction stream 80 that is fed back into, for instance, the end flash separator 50 while bypassing the nitrogen stripper column 20.
  • the amount of nitrogen in the liquid hydrocarbon product stream 90 can be influenced.
  • the vapour recycle flow control valve 88 may be controlled in response to a signal from a quality measurement instrument QMI that is optionally provided in the liquid hydrocarbon product line 90.
  • Table 1 Holding mode; Reference numbers correspond to Figure 1.
  • cryogenic hydrocarbon composition 8 was assumed to consist for more than 90 mol% of a mixture of nitrogen and methane
  • the amount of nitrogen (1.654 mol%) and methane (98.204 mol%) is more than
  • the amount of methane in the discharged vapour fraction 80 could be kept at about 80 mol% and well within the range of between 10 mol% and 25 mol% while at the same time the nitrogen content in the liquid
  • hydrocarbon product stream 90 was kept within the target of close to 1.0 mol% and not exceeding 1.1 mol%.
  • methane was added to the process via the boil-off gas supply line 230, while in loading mode this was about 4.4 kg/s.
  • the split ratio in the initial stream splitter 9 was about 75 % in both cases. In holding mode no vapour was guided through the vapour bypass line 76, while in the loading mode 30% of the compressed vapour 70 was guided through the vapour bypass line 76 in order to accommodate the additional vapour brought about by the additional inflow of boil-off gas.
  • the liquid recycle 13 in the loading mode also went up, from about 8% to about 41% of the condensed fraction in the condensed fraction discharge line 37.
  • the additional flow of condensed fraction is a result of additional re-condensed methane.
  • the liquefaction system 100 in the calculation used a line up as shown in Figure 2 with a mixed refrigerant in the compressed refrigerant line 120 with a composition as listed in Table 3 in the column labelled "120".
  • the pressure in the compressed refrigerant line 120 was 58 bara, in loading mode higher, 61 bara.
  • the aggregated pressure drop in the lower and upper LMR tube bundles (183 and 184, respectively) of the cryogenic heat exchanger is 13 bar in both cases.
  • the pressure drop imposed by the auxiliary refrigerant stream flow control valve 135 was 39 bar in the holding mode case and 42 bar in the loading mode operation so that the shell pressure in shell side 186 of the cryogenic heat exchanger 180 was the same for both the holding mode as the loading mode.
  • the relative flow rate of the auxiliary refrigerant stream 132 consisted of 11 % of the total LMR flow rate in LMR line 131. In loading mode this was 18 %. Also the actual flow rate was 1.6x higher than in the holding mode case, but the separation between HMR and LMR in MR separator 128 was made to favour HMR a little bit more in the loading mode operation than in the holding mode operation .
  • cryogenic hydrocarbon composition was assumed to contain no hydrocarbons heavier than methane (C2+ hydrocarbons), such as could be the case if the cryogenic hydrocarbon composition is derived from non-conventional gas sources, such as coal bed methane, shale gas, or perhaps certain synthetic sources.
  • non-conventional gas sources such as coal bed methane, shale gas, or perhaps certain synthetic sources.
  • the proposed methods and apparatus may also be applied where the cryogenic hydrocarbon
  • composition would contain up to about 15 mol% of C2+ hydrocarbons, including one or more selected from the group consisting of ethane, propane, i-butane, n-butane, and pentane. In essence these additional C2+

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Abstract

De l'azote est retiré d'une composition d'hydrocarbures cryogéniques. Au moins une première partie de la composition d'hydrocarbures cryogéniques est introduite dans une colonne de strippage d'azote. La colonne de strippage d'azote fonctionne à une pression de strippage. Une vapeur de strippage est amenée à passer à travers la colonne de strippage d'azote, comprenant au moins une partie de strippage d'une vapeur de traitement comprimée qui a été produite à partir du liquide ayant subi le strippage d'azote, qui a été dépressurisé après son soutirage de la colonne de strippage d'azote. Un reflux est généré et mettant en jeu une condensation partielle de la vapeur de tête de la colonne de strippage d'azote par passage de chaleur de la vapeur de tête à un courant de réfrigérant auxiliaire à un dispositif de refroidissement. Un gaz d'échappement consistant en une fraction de vapeur non condensée provenant de la vapeur de tête est déchargé. Le dispositif de refroidissement est ajusté pour réguler une valeur de chauffage de la fraction de vapeur qui est déchargée.
PCT/EP2012/074959 2011-12-12 2012-12-10 Procédé et appareil pour retirer de l'azote d'une composition d'hydrocarbures cryogéniques WO2013087571A2 (fr)

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CN201280061162.5A CN104011489B (zh) 2011-12-12 2012-12-10 用于从低温烃类组合物中去除氮气的方法和装置
CA2858155A CA2858155C (fr) 2011-12-12 2012-12-10 Procede et appareil pour retirer de l'azote d'une composition d'hydrocarbures cryogeniques
RU2014128666A RU2607708C2 (ru) 2011-12-12 2012-12-10 Способ и устройство для удаления азота из криогенной углеводородной композиции
AU2012354774A AU2012354774B2 (en) 2011-12-12 2012-12-10 Method and apparatus for removing nitrogen from a cryogenic hydrocarbon composition
US14/364,262 US20140345319A1 (en) 2011-12-12 2012-12-10 Method and apparatus for removing nitrogen from a cryogenic hydrocarbon composition
MYPI2014701217A MY185531A (en) 2011-12-12 2012-12-10 Method and apparatus for removing nitrogen from a cryogenic hydrocarbon composition

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AU2012354774B2 (en) 2015-09-10
MY185531A (en) 2021-05-19
US20140345319A1 (en) 2014-11-27
RU2014128666A (ru) 2016-02-10
CN104011489B (zh) 2016-03-23
CA2858155A1 (fr) 2013-06-20
CA2858155C (fr) 2020-04-28
CN104011489A (zh) 2014-08-27
AU2012354774A1 (en) 2013-07-18
RU2607708C2 (ru) 2017-01-10
WO2013087571A3 (fr) 2014-05-01

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