WO2009126604A1 - Methods and configuration of boil-off gas handling in lng regasification terminals - Google Patents

Methods and configuration of boil-off gas handling in lng regasification terminals Download PDF

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Publication number
WO2009126604A1
WO2009126604A1 PCT/US2009/039740 US2009039740W WO2009126604A1 WO 2009126604 A1 WO2009126604 A1 WO 2009126604A1 US 2009039740 W US2009039740 W US 2009039740W WO 2009126604 A1 WO2009126604 A1 WO 2009126604A1
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WO
WIPO (PCT)
Prior art keywords
gas
boil
lng
reliquefied
regasification
Prior art date
Application number
PCT/US2009/039740
Other languages
French (fr)
Inventor
John Mak
Original Assignee
Fluor Technologies Corporation
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 Fluor Technologies Corporation filed Critical Fluor Technologies Corporation
Priority to CN200980115754.9A priority Critical patent/CN102084171B/en
Priority to EP09730115.4A priority patent/EP2265854A4/en
Priority to CA2718840A priority patent/CA2718840A1/en
Priority to MX2010010706A priority patent/MX2010010706A/en
Priority to US12/936,070 priority patent/US8893515B2/en
Publication of WO2009126604A1 publication Critical patent/WO2009126604A1/en

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C9/00—Methods or apparatus for discharging liquefied or solidified gases from vessels not under pressure
    • F17C9/02—Methods or apparatus for discharging liquefied or solidified gases from vessels not under pressure with change of state, e.g. vaporisation
    • F17C9/04—Recovery of thermal energy
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C9/00—Methods or apparatus for discharging liquefied or solidified gases from vessels not under pressure
    • F17C9/02—Methods or apparatus for discharging liquefied or solidified gases from vessels not under pressure with change of state, e.g. vaporisation
    • 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
    • F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
    • 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
    • F25J1/0025—Boil-off gases "BOG" from storages
    • 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
    • F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
    • F25J1/003—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
    • 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"
    • F25J1/004—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" by flash gas recovery
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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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    • F25J1/0032—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"
    • F25J1/0045—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" by vaporising a liquid return stream
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    • F25J1/005—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 an "external" refrigerant stream in a closed vapor compression cycle by expansion of a gaseous refrigerant stream with extraction of work
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    • F25J1/0221—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process using the cold stored in an external cryogenic component in an open refrigeration loop
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    • 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
    • F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
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    • F25J1/0221—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process using the cold stored in an external cryogenic component in an open refrigeration loop
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    • F25J1/0228—Coupling of the liquefaction unit to other units or processes, so-called integrated processes
    • F25J1/0229—Integration with a unit for using hydrocarbons, e.g. consuming hydrocarbons as feed stock
    • F25J1/023—Integration with a unit for using hydrocarbons, e.g. consuming hydrocarbons as feed stock for the combustion as fuels, i.e. integration with the fuel gas system
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    • F25J1/0285—Combination of different types of drivers mechanically coupled to the same refrigerant compressor, possibly split on multiple compressor casings
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    • F17C2223/0146—Two-phase
    • F17C2223/0153—Liquefied gas, e.g. LPG, GPL
    • F17C2223/0161—Liquefied gas, e.g. LPG, GPL cryogenic, e.g. LNG, GNL, PLNG
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2265/00—Effects achieved by gas storage or gas handling
    • F17C2265/03—Treating the boil-off
    • F17C2265/032—Treating the boil-off by recovery
    • F17C2265/033—Treating the boil-off by recovery with cooling
    • F17C2265/034—Treating the boil-off by recovery with cooling with condensing the gas phase
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2265/00—Effects achieved by gas storage or gas handling
    • F17C2265/03—Treating the boil-off
    • F17C2265/032—Treating the boil-off by recovery
    • F17C2265/036—Treating the boil-off by recovery with heating
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2265/00—Effects achieved by gas storage or gas handling
    • F17C2265/03—Treating the boil-off
    • F17C2265/032—Treating the boil-off by recovery
    • F17C2265/037—Treating the boil-off by recovery with pressurising
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2265/00—Effects achieved by gas storage or gas handling
    • F17C2265/05—Regasification
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2265/00—Effects achieved by gas storage or gas handling
    • F17C2265/07—Generating electrical power as side effect
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2270/00—Applications
    • F17C2270/01—Applications for fluid transport or storage
    • F17C2270/0134—Applications for fluid transport or storage placed above the ground
    • F17C2270/0136—Terminals
    • 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
    • F25J2205/00—Processes or apparatus using other separation and/or other processing means
    • F25J2205/90—Mixing of components
    • 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
    • F25J2210/00—Processes characterised by the type or other details of the feed stream
    • F25J2210/62—Liquefied natural gas [LNG]; Natural gas liquids [NGL]; Liquefied petroleum gas [LPG]
    • 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
    • F25J2215/00—Processes characterised by the type or other details of the product stream
    • F25J2215/02—Mixing or blending of fluids to yield a certain product

Definitions

  • the field of the invention is natural gas processing, especially as it relates to handling of boil-off gas and Wobbe index control in LNG regasif ⁇ cation terminals.
  • U.S. pipeline gas is generally very lean, with heating values ranging from 1000 to 1070 Btu/scf, and more recently, FERC (the Federal Energy Regulatory Commission) has established guidelines and specifications for natural gas import. These guidelines require the Wobbe Index of the import gas to be within +/-4 % with respect to the local gas quality, with a maximum value of 1400. California, which traditionally uses a very lean gas, requires a significantly lower Wobbe Index for the import gas. For example, the local air emission agency SCAQMD (Southern California Air Quality Management District) specifies a maximum Wobbe Index of 1360.
  • Figure 2 illustrates the reduction in Wobbe Index before and after nitrogen dilution for the various LNG sources, up to a maximum 3 mol% N2 limit.
  • Figure 2 illustrates the reduction in Wobbe Index before and after nitrogen dilution for the various LNG sources, up to a maximum 3 mol% N2 limit.
  • less than half of the LNG sources meet the California Wobbe Index even with maximum nitrogen dilution.
  • changes in Wobbe Index due to weathering in the LNG storage may result in off specification product.
  • anti-weathering configurations can be implemented to reduce increase of Wobbe index as described in U.S. Pat. No. 7,201,002.
  • the boil-off vapor is condensed within the confines of the tank using LNG refrigeration and pressure regulation.
  • boil-off vapors can be reliquef ⁇ ed on board to control Wobbe index and product loss.
  • such configurations are typically limited to either on-board systems that are inflexible with respect to changing and relatively large vapor loads, and/or will require cryogenic equipment and relatively large capital cost.
  • Other systems and methods with similar difficulties are described in U.S. Pat. Nos. 3,894,856 and 4,675,037, U.S. Pat. App. No. 2008/0308175, and WO 2005/047761.
  • the present inventive subject matter is directed to methods and plants of maintaining Wobbe index of LNG in a storage and regasification facility. Contemplated methods and Attny DktNo. 100325.0330PCT
  • plants allow for operational flexibility and stable storage tank pressure control while maintaining the Wobbe index throughout various storage, loading, and unloading conditions.
  • the boil-off gas is compressed in a compression unit and a large fraction of the compressed boil-off gas is further processed while another fraction is routed (typically after further compression) to the fuel header of a combustor or other destination suitable for relatively lean gas.
  • processing of the compressed boil-off gas may be predominantly (or even exclusively) recondensation in a traditional LNG condenser using sendout LNG or primarily reliquefaction and separation of nitrogen wherein the reliquef ⁇ ed lean LNG is fed back to the tank (directly or via intermediate storage) while the nitrogen is recycled back to combine with the boil-off gas.
  • a method of Wobbe index control of LNG in an LNG storage tank includes a step of fluidly coupling an LNG storage tank to a regasification unit such that the tank provides LNG to the regasif ⁇ cation unit.
  • a compression unit is further fluidly coupled to the LNG storage tank such that the tank provides cold boil-off gas to the compression unit, wherein the compression unit forms a compressed boil-off gas.
  • a first stream of the compressed boil-off gas is heat- exchanged using the cold boil-off gas to form cooled compressed boil-off gas
  • a first portion of the cooled compressed boil-off gas is combined with the LNG.
  • a second portion of the cooled compressed boil-off gas is partially reliquefied, and nitrogen is separated from the reliquef ⁇ ed boil-off gas to produce a lean reliquefied boil-off gas.
  • the lean reliquefied boil-off gas is then fed into the LNG storage tank.
  • a LNG storage and regasification plant will include a LNG storage tank that is fluidly coupled to a regasification unit to provide LNG from the tank to the regasification unit.
  • a compression unit is also coupled to the LNG storage tank to provide cold boil-off gas from the tank to the compression unit, wherein the compression unit is configured to form a compressed boil-off gas.
  • a heat- exchanger cools a first stream of the compressed boil-off gas using the cold boil-off gas to so form a cooled compressed boil-off gas, and a first conduit is provided to combine a first portion of the cooled compressed boil-off gas with the LNG.
  • Contemplated plants further include a cooler that reliquefies a second portion of the cooled compressed boil-off gas to form a partially reliquefied boil-off gas, and a separator separates nitrogen from the Attny DktNo. 100325.0330PCT
  • a second conduit configured is provided to feed the lean reliquefied boil-off gas into the LNG storage tank.
  • the cooled compressed boil-off gas and the LNG are combined and fed into a recondenser that is typically upstream of the regasification unit. It is also generally preferred that the LNG provides at least some of the refrigeration duty for the reliquefaction, which is most preferably performed in cold box.
  • nitrogen is separated from the reliquefied boil-off gas by expansion of the reliquefied boil-off gas in a JT valve or an expander and by separating the so expanded reliquefied boil-off gas in a separator. Most typically, the nitrogen is then combined with the cold boil-off gas.
  • a second stream of the compressed boil-off gas is compressed and supplies fuel gas to the facility in a combustor or other process that employs lean gas.
  • the plant operation is controlled such that the ratio between the first and second portions is increased when the flow of the LNG to the regasification unit increases.
  • contemplated configurations provide operational flexibility for the LNG regasification facility allowing reliquefying boiloff gas ranging from 1 MMscfd to 50 MMscfd at LNG sendout rates ranging from 100 MMscfd to 2000 MMscfd. Such configuration can control the Wobbe Index of LNG sendout while requiring minimum energy consumption in the boiloff gas reliquefaction process.
  • Figure 1 is an exemplary illustration for variations in the LNG composition for LNG originating from various geographic sources.
  • Figure 2 is an exemplary illustration for the reduction in Wobbe Index before and after nitrogen dilution for the various LNG sources of Figure 1.
  • Figure 3 is an exemplary scheme for a plant configuration according to the inventive subject matter. Attny DktNo. 100325.0330PCT
  • Wobbe index control of LNG in an LNG storage tank coupled to a regasification unit may be achieved by use of a compression unit that compresses cold boil-off gas from the tank, and by heat exchanging a first stream of the compressed boil-off gas using the cold boil-off gas or LNG to form cooled compressed boil-off gas.
  • a compression unit that compresses cold boil-off gas from the tank, and by heat exchanging a first stream of the compressed boil-off gas using the cold boil-off gas or LNG to form cooled compressed boil-off gas.
  • One portion of the cooled compressed boil-off gas is then combined with the LNG, while another portion of the cooled compressed boil-off gas is reliquefied.
  • Nitrogen is then separated from the reliquefied boil-off gas to produce a lean (i.e., C2+ content of less than 3 mol%, and more typically less than 2 mol%) reliquefied boil-off gas that is then fed into the LNG storage tank.
  • a lean i.e., C2+ content of less than 3 mol%, and more typically less than 2 mol%
  • LNG storage and regasification plants suitable for use herein will typically include a LNG storage tank that provides LNG to a regasification unit and that provides boil- off gas to a compression unit. At least a portion of the compressed boil-off gas is then cooled in a heat exchanger (typically using refrigeration content of the boil-off vapor and/or the LNG), and the so formed cooled compressed boil-off gas is then split into two streams, one that is combined with the LNG (typically via a condenser), and one that is further cooled in a cooler to reliquefaction.
  • a heat exchanger typically using refrigeration content of the boil-off vapor and/or the LNG
  • a separator can be implemented to allow separation of nitrogen or other non-condensable components from the reliquefied boil-off gas to so produce a lean reliquefied boil-off gas.
  • the lean reliquefied boil-off gas is then directly (or indirectly via a storage tank) fed into the LNG storage tank for Wobbe index control.
  • FIG. 3 is one exemplary configuration of a LNG storage and regasification plant in which a boil-off gas reliquefaction unit is integrated into an LNG receiving terminal (feed line to the tank not shown).
  • the boil-off gas from the storage tank stream 1 typically at a flow rate of 8 to 16 MMscfd, at a temperature of -160 0 C, is heated in exchanger 50 to stream 4 using the compressed boil-off gas stream 6, to about -20 0 C to 10 0 C, and then compressed by four stage BOG compressor 51 , 52, and 53, and 90 from atmospheric pressure to about 8.5 barg or higher.
  • the discharge pressure is preferably between 8 barg and 25 barg Attny DktNo. 100325.0330PCT
  • Compressor discharges are cooled in exchangers 54, 55, and 56 to form stream 5 using ambient air or cooling water.
  • the refrigeration content from LNG is utilized for cooling since a lower temperature can be achieved, which can significantly reduce power consumption of the boil-off gas compressor while at the same time heating requirement for LNG regasification is reduced.
  • the pressurized boil-off gas stream 5 from exchanger 56 is split into at least two streams, 6 and 7.
  • Stream 7 is further compressed to 15 to 25 barg by the fourth BOG compression stage 90 forming stream 91 that is sent to fuel gas system supplying fuel gas to a gas turbine power generator or other combustion header.
  • Stream 6 is cooled in exchanger 50 forming stream 8, typically at -140 0 C, which is then further split into streams 9 and 10.
  • stream 9 is mixed with the sendout LNG stream 22 from the storage tank, forming a condensed stream 21. Condensation occurs in conventional boil-off gas recondenser 23, forming a subcooled stream 24 which is pumped by pump 25 to so form the high pressure sendout stream 26 that is fed to the LNG vaporizers (not shown).
  • the compressed boil-off gas stream 10 is further cooled and liquefied in the cold box 57 forming stream 11, typically at -17O 0 C. Cooling is supplied by refrigeration produced using a three stage nitrogen compressor 62, 63, and 64. Compressor discharges are cooled in exchangers 66, 67, and 68 using ambient air or cooling water. Nitrogen is compressed from a suction pressure of 8 to 11 barg to a final discharge pressure of about 36 to 50 barg, cooled in the cold box 57, and then expanded in turbo expander 61 to stream 16.
  • the refrigeration content from stored or sendout LNG is utilized for cooling, which can significantly reduce the power consumption of the nitrogen compressor while also reducing the heat for LNG regasification.
  • the refrigeration content from LNG (via a heat transfer fluid) can also be utilized for cooling in the box cold using LNG stream 80 (to stream 81), which further significantly reduces the power consumption of the nitrogen compressor.
  • the turbo expander 61 produces cryogenic refrigeration in stream 16 at about -180 0 C for boil-off gas liquefaction and for cooling the compressed nitrogen stream 19 from ambient temperature to form stream 15 at about -145 0 C.
  • the expander also generates power which reduces the power consumption by the nitrogen compressor.
  • the operating pressure of nitrogen compressor is dependent on the Attny DktNo. 100325.0330PCT
  • boil-off gas compressor discharge pressure A higher boil-off gas compressor discharge pressure will reduce the refrigeration duty requirement.
  • the total power consumption of the boil-off gas reliquefaction unit is about 5 to 6 MW when cooling is by cooling water. When the LNG cold is utilized in cooling, the overall power consumption can be reduced, typically by as much as 50%.
  • the condensate can be pressured using the potential energy in stream 11 or free drained to the storage tank, thus eliminating the use of pump 60.
  • the flash gas stream 2, which mostly comprises the non-condensable nitrogen, is recycled back to the boil-off gas compressor suction to form stream 3.
  • low pressure cryogenic boil-off gas from a LNG storage unit is first heated by compressed boil-off gas to about ambient temperature, and compressed to 8 barg or higher pressure. A portion of the compressed boil- off gas is then cooled and used as fuel gas to gas turbines, while another portion is cooled by the low pressure cryogenic boil-off gas to a lower temperature prior to feeding into a cold box for reliquefaction and/or prior to recondensation by mixing with the sendout LNG.
  • the fuel gas to the gas turbine may be further compressed as appropriate to meet gas turbine fuel pressure requirement.
  • a flashed condensate is produced from the reliquefied boil-off gas and is pressurized and returned to the storage tank for Wobbe Index control.
  • carbon steel material can be used for the construction of the boil-off gas compressor which significantly saves equipment cost.
  • the condensate from the boil-off gas reliquefaction can be either returned to the LNG storage or to a separate storage tank that is reserved for holding lean re liquefied LNG for dilution of rich LNG in a later part of the LNG regasification cycle (due to weathering), thereby maintaining the Wobbe Index throughout the regasification process. Consequently, it should be recognized that contemplated configurations and methods eliminate the uncertainty of Wobbe Index changes due to weathering in LNG storage tanks which are typically designed for 0.05 to 0.2 volume % boil-off per day. This is particularly critical in environmental sensitive markets where a stringent Wobbe Index must be met (e.g., California market).
  • contemplated configurations and methods provide operational flexibility by liquefying the boil-off gas at an optimum pressure while allowing a portion of the pressurized boil-off gas to be used as fuel gas to gas turbine power generator and/or routed to the boil-off gas recondenser which minimizes the reliquefaction power consumption during peak sendout operation.

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Abstract

A LNG storage and regasification plant includes a reliquefaction unit in which boil- off vapors from the storage tanks are re liquefied and recycled back to the LNG storage tanks for tank pressure and Wobbe index control. Preferably, LNG cold is used for reliquefaction and operational flexibility is achieved by feeding a portion of the pressurized boil-off gas to a fuel gas header and/or to be recondensed by the sendout LNG.

Description

Attny DktNo. 100325.0330PCT
METHODS AND CONFIGURATION OF BOIL-OFF GAS HANDLING IN LNG
REGASFICATION TERMINALS
This application claims priority to our U.S. provisional patent application with serial number 61/044302, filed April 11, 2008, which is incorporated by reference herein.
Field of the Invention
[0001] The field of the invention is natural gas processing, especially as it relates to handling of boil-off gas and Wobbe index control in LNG regasifϊcation terminals.
Background
[0002] U.S. pipeline gas is generally very lean, with heating values ranging from 1000 to 1070 Btu/scf, and more recently, FERC (the Federal Energy Regulatory Commission) has established guidelines and specifications for natural gas import. These guidelines require the Wobbe Index of the import gas to be within +/-4 % with respect to the local gas quality, with a maximum value of 1400. California, which traditionally uses a very lean gas, requires a significantly lower Wobbe Index for the import gas. For example, the local air emission agency SCAQMD (Southern California Air Quality Management District) specifies a maximum Wobbe Index of 1360.
[0003] Unfortunately, the heating value of unprocessed import LNG is often significantly higher due to the relatively high ethane and propane content, which is not only incompatible with local rules and regulations, but also incompatible with many residential, commercial, and industrial burners. Examples for the wide variations in LNG composition, heating value, and Wobbe Index for LNG export terminals in the Atlantic, Pacific basins and the Middle East are shown in Figure 1. As can be seen from Figure 1, only Alaska's LNG can meet the gas quality specifications without nitrogen dilution for import to California while the remaining LNG requires nitrogen blending and/or NGL (natural gas liquids) extraction.
[0004] Figure 2 illustrates the reduction in Wobbe Index before and after nitrogen dilution for the various LNG sources, up to a maximum 3 mol% N2 limit. As can be taken from Figure 2, less than half of the LNG sources meet the California Wobbe Index even with maximum nitrogen dilution. Moreover, due to the relatively tight margins on meeting the California Wobbe Index specification, changes in Wobbe Index due to weathering in the LNG storage may result in off specification product. The weathering effect of LNG from Attny DktNo. 100325.0330PCT
natural boil-off from the storage tanks enriches LNG in heavier components (i.e., C2+) over time, eventually rendering the weathered gas unacceptable as a pipeline gas with a higher Wobbe Index. While the weathering effect typically increases the Wobbe Index by a relatively small amount (e.g., about 3 to 6 points), such increase is problematic for marginal LNGs.
[0005] In various presently known LNG processing configurations to meet the Wobbe Index, non-methane components are removed from the LNG in a process that vaporizes the LNG in a demethanizer using a reboiler and re-condenses the demethanizer overhead to the sendout liquid that is then pumped and vaporized (see e.g., U.S. Pat. No. 6,564,579). While such configurations and methods typically operate satisfactorily for heating value or Wobbe Index control, they will require markets for the extracted NGL products, which are not always available. Moreover, in most cases where LNG terminals are configured for BTU delivery to commercial and residential users, there are no economic incentives for NGL extraction.
[0006] Alternatively, anti-weathering configurations can be implemented to reduce increase of Wobbe index as described in U.S. Pat. No. 7,201,002. Here the boil-off vapor is condensed within the confines of the tank using LNG refrigeration and pressure regulation. Similarly, as shown in U.S. Pat. No. 6,530,241, boil-off vapors can be reliquefϊed on board to control Wobbe index and product loss. However, such configurations are typically limited to either on-board systems that are inflexible with respect to changing and relatively large vapor loads, and/or will require cryogenic equipment and relatively large capital cost. Other systems and methods with similar difficulties are described in U.S. Pat. Nos. 3,894,856 and 4,675,037, U.S. Pat. App. No. 2008/0308175, and WO 2005/047761.
[0007] Therefore, while various LNG heating value control methods are known in the art, all or almost all of them suffer from one or more disadvantages, especially where import LNG is used, where NGL markets do not exist, and where the Wobbe Index of the import LNG only marginally meets local specifications. Thus, there is still a need for improved configurations and methods for maintaining the Wobbe Index while providing operating flexibility for the LNG regasification terminals with lower energy consumption.
Summary of the Invention
[0008] The present inventive subject matter is directed to methods and plants of maintaining Wobbe index of LNG in a storage and regasification facility. Contemplated methods and Attny DktNo. 100325.0330PCT
plants allow for operational flexibility and stable storage tank pressure control while maintaining the Wobbe index throughout various storage, loading, and unloading conditions.
[0009] Most preferably, the boil-off gas is compressed in a compression unit and a large fraction of the compressed boil-off gas is further processed while another fraction is routed (typically after further compression) to the fuel header of a combustor or other destination suitable for relatively lean gas. Depending on operational status of the tank, processing of the compressed boil-off gas may be predominantly (or even exclusively) recondensation in a traditional LNG condenser using sendout LNG or primarily reliquefaction and separation of nitrogen wherein the reliquefϊed lean LNG is fed back to the tank (directly or via intermediate storage) while the nitrogen is recycled back to combine with the boil-off gas.
[0010] In one especially preferred aspect of the inventive subject matter, a method of Wobbe index control of LNG in an LNG storage tank includes a step of fluidly coupling an LNG storage tank to a regasification unit such that the tank provides LNG to the regasifϊcation unit. A compression unit is further fluidly coupled to the LNG storage tank such that the tank provides cold boil-off gas to the compression unit, wherein the compression unit forms a compressed boil-off gas. In another step, a first stream of the compressed boil-off gas is heat- exchanged using the cold boil-off gas to form cooled compressed boil-off gas, and in yet another step, a first portion of the cooled compressed boil-off gas is combined with the LNG. In a still further step, a second portion of the cooled compressed boil-off gas is partially reliquefied, and nitrogen is separated from the reliquefϊed boil-off gas to produce a lean reliquefied boil-off gas. The lean reliquefied boil-off gas is then fed into the LNG storage tank.
[0011] Therefore, and viewed from a different perspective, a LNG storage and regasification plant will include a LNG storage tank that is fluidly coupled to a regasification unit to provide LNG from the tank to the regasification unit. A compression unit is also coupled to the LNG storage tank to provide cold boil-off gas from the tank to the compression unit, wherein the compression unit is configured to form a compressed boil-off gas. A heat- exchanger cools a first stream of the compressed boil-off gas using the cold boil-off gas to so form a cooled compressed boil-off gas, and a first conduit is provided to combine a first portion of the cooled compressed boil-off gas with the LNG. Contemplated plants further include a cooler that reliquefies a second portion of the cooled compressed boil-off gas to form a partially reliquefied boil-off gas, and a separator separates nitrogen from the Attny DktNo. 100325.0330PCT
reliquefied boil-off gas to so produce a lean reliquefϊed boil-off gas. A second conduit configured is provided to feed the lean reliquefied boil-off gas into the LNG storage tank.
[0012] It is generally preferred that the cooled compressed boil-off gas and the LNG are combined and fed into a recondenser that is typically upstream of the regasification unit. It is also generally preferred that the LNG provides at least some of the refrigeration duty for the reliquefaction, which is most preferably performed in cold box. In further contemplated aspects of the inventive subject matter, nitrogen is separated from the reliquefied boil-off gas by expansion of the reliquefied boil-off gas in a JT valve or an expander and by separating the so expanded reliquefied boil-off gas in a separator. Most typically, the nitrogen is then combined with the cold boil-off gas.
[0013] Additionally, it is generally preferred that a second stream of the compressed boil-off gas is compressed and supplies fuel gas to the facility in a combustor or other process that employs lean gas. In particularly preferred aspects, the plant operation is controlled such that the ratio between the first and second portions is increased when the flow of the LNG to the regasification unit increases. Viewed from another perspective, contemplated configurations provide operational flexibility for the LNG regasification facility allowing reliquefying boiloff gas ranging from 1 MMscfd to 50 MMscfd at LNG sendout rates ranging from 100 MMscfd to 2000 MMscfd. Such configuration can control the Wobbe Index of LNG sendout while requiring minimum energy consumption in the boiloff gas reliquefaction process.
[0014] Various objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention.
Brief Description of the Drawing
[0015] Figure 1 is an exemplary illustration for variations in the LNG composition for LNG originating from various geographic sources.
[0016] Figure 2 is an exemplary illustration for the reduction in Wobbe Index before and after nitrogen dilution for the various LNG sources of Figure 1.
[0017] Figure 3 is an exemplary scheme for a plant configuration according to the inventive subject matter. Attny DktNo. 100325.0330PCT
Detailed Description
[0018] The inventor has discovered that changes in Wobbe Index due to weathering in the LNG storage tank can be reduced, and typically entirely prevented where at least part of the boil-off vapors are re liquefied during storage and where at least part of the vapors are condensed in sendout LNG. Further flexibility is provided by routing at least another portion of the vapors to a fuel header or other device that uses lean natural gas.
[0019] For example, in one especially preferred method, Wobbe index control of LNG in an LNG storage tank coupled to a regasification unit may be achieved by use of a compression unit that compresses cold boil-off gas from the tank, and by heat exchanging a first stream of the compressed boil-off gas using the cold boil-off gas or LNG to form cooled compressed boil-off gas. One portion of the cooled compressed boil-off gas is then combined with the LNG, while another portion of the cooled compressed boil-off gas is reliquefied. Nitrogen is then separated from the reliquefied boil-off gas to produce a lean (i.e., C2+ content of less than 3 mol%, and more typically less than 2 mol%) reliquefied boil-off gas that is then fed into the LNG storage tank.
[0020] Thus, LNG storage and regasification plants suitable for use herein will typically include a LNG storage tank that provides LNG to a regasification unit and that provides boil- off gas to a compression unit. At least a portion of the compressed boil-off gas is then cooled in a heat exchanger (typically using refrigeration content of the boil-off vapor and/or the LNG), and the so formed cooled compressed boil-off gas is then split into two streams, one that is combined with the LNG (typically via a condenser), and one that is further cooled in a cooler to reliquefaction. Where desired, a separator can be implemented to allow separation of nitrogen or other non-condensable components from the reliquefied boil-off gas to so produce a lean reliquefied boil-off gas. The lean reliquefied boil-off gas is then directly (or indirectly via a storage tank) fed into the LNG storage tank for Wobbe index control.
[0021] Figure 3 is one exemplary configuration of a LNG storage and regasification plant in which a boil-off gas reliquefaction unit is integrated into an LNG receiving terminal (feed line to the tank not shown). Here, the boil-off gas from the storage tank stream 1, typically at a flow rate of 8 to 16 MMscfd, at a temperature of -160 0C, is heated in exchanger 50 to stream 4 using the compressed boil-off gas stream 6, to about -20 0C to 10 0C, and then compressed by four stage BOG compressor 51 , 52, and 53, and 90 from atmospheric pressure to about 8.5 barg or higher. The discharge pressure is preferably between 8 barg and 25 barg Attny DktNo. 100325.0330PCT
or as needed to meet the fuel gas pressure requirement of the gas turbine power generator (not shown). Compressor discharges are cooled in exchangers 54, 55, and 56 to form stream 5 using ambient air or cooling water. However, it is especially preferred that the refrigeration content from LNG is utilized for cooling since a lower temperature can be achieved, which can significantly reduce power consumption of the boil-off gas compressor while at the same time heating requirement for LNG regasification is reduced.
[0022] The pressurized boil-off gas stream 5 from exchanger 56 is split into at least two streams, 6 and 7. Stream 7 is further compressed to 15 to 25 barg by the fourth BOG compression stage 90 forming stream 91 that is sent to fuel gas system supplying fuel gas to a gas turbine power generator or other combustion header. Stream 6 is cooled in exchanger 50 forming stream 8, typically at -140 0C, which is then further split into streams 9 and 10. During peak sendout operation when power supply is limited, stream 9 is mixed with the sendout LNG stream 22 from the storage tank, forming a condensed stream 21. Condensation occurs in conventional boil-off gas recondenser 23, forming a subcooled stream 24 which is pumped by pump 25 to so form the high pressure sendout stream 26 that is fed to the LNG vaporizers (not shown).
[0023] The compressed boil-off gas stream 10 is further cooled and liquefied in the cold box 57 forming stream 11, typically at -17O0C. Cooling is supplied by refrigeration produced using a three stage nitrogen compressor 62, 63, and 64. Compressor discharges are cooled in exchangers 66, 67, and 68 using ambient air or cooling water. Nitrogen is compressed from a suction pressure of 8 to 11 barg to a final discharge pressure of about 36 to 50 barg, cooled in the cold box 57, and then expanded in turbo expander 61 to stream 16. Preferably, the refrigeration content from stored or sendout LNG is utilized for cooling, which can significantly reduce the power consumption of the nitrogen compressor while also reducing the heat for LNG regasification. Optionally, the refrigeration content from LNG (via a heat transfer fluid) can also be utilized for cooling in the box cold using LNG stream 80 (to stream 81), which further significantly reduces the power consumption of the nitrogen compressor.
[0024] In addition to the refrigeration available from LNG, the turbo expander 61 produces cryogenic refrigeration in stream 16 at about -1800C for boil-off gas liquefaction and for cooling the compressed nitrogen stream 19 from ambient temperature to form stream 15 at about -1450C. The expander also generates power which reduces the power consumption by the nitrogen compressor. The operating pressure of nitrogen compressor is dependent on the Attny DktNo. 100325.0330PCT
boil-off gas compressor discharge pressure. A higher boil-off gas compressor discharge pressure will reduce the refrigeration duty requirement. The total power consumption of the boil-off gas reliquefaction unit is about 5 to 6 MW when cooling is by cooling water. When the LNG cold is utilized in cooling, the overall power consumption can be reduced, typically by as much as 50%.
[0025] The condensate stream 11 from the cold box typically, at -160 0F, is let down in pressure in JT valve 58 to flash drum 59 forming a flash liquid stream 13 typically at -170 0C, which is pumped by pump 60 forming stream 14 to the storage tank. For further energy savings, the condensate can be pressured using the potential energy in stream 11 or free drained to the storage tank, thus eliminating the use of pump 60. The flash gas stream 2, which mostly comprises the non-condensable nitrogen, is recycled back to the boil-off gas compressor suction to form stream 3.
[0026] Therefore, it should be appreciated that operational flexibility to accommodate variable volumes of boil-off vapors is achieved by providing conduits via which cooled and compressed boil-off vapor can be fed to a fuel gas header for combustion (or other sink), sendout LNG for condensation and adsorption, and/or a liquefaction unit in which the cooled and compressed boil-off vapor is re liquefied and fed back to the storage tank to reduce or maintain Wobbe index. Thus, it should be appreciated that contemplated LNG storage configurations and methods will reduce or even eliminate adverse effects of weathering and so provide Wobbe index control without the need for additional plant components.
[0027] In especially preferred configurations and methods, low pressure cryogenic boil-off gas from a LNG storage unit is first heated by compressed boil-off gas to about ambient temperature, and compressed to 8 barg or higher pressure. A portion of the compressed boil- off gas is then cooled and used as fuel gas to gas turbines, while another portion is cooled by the low pressure cryogenic boil-off gas to a lower temperature prior to feeding into a cold box for reliquefaction and/or prior to recondensation by mixing with the sendout LNG. The fuel gas to the gas turbine may be further compressed as appropriate to meet gas turbine fuel pressure requirement. Most typically, a flashed condensate is produced from the reliquefied boil-off gas and is pressurized and returned to the storage tank for Wobbe Index control. It should be especially appreciated that the feed exchange produces a cryogenic high pressure gas to the cold box, which significantly reduces the refrigeration duty in the cold box of the known design, resulting in power savings of at least 30 to 40%. It should also be appreciated Attny DktNo. 100325.0330PCT
that with close to ambient temperature operation, carbon steel material can be used for the construction of the boil-off gas compressor which significantly saves equipment cost.
[0028] It is further preferred that the condensate from the boil-off gas reliquefaction can be either returned to the LNG storage or to a separate storage tank that is reserved for holding lean re liquefied LNG for dilution of rich LNG in a later part of the LNG regasification cycle (due to weathering), thereby maintaining the Wobbe Index throughout the regasification process. Consequently, it should be recognized that contemplated configurations and methods eliminate the uncertainty of Wobbe Index changes due to weathering in LNG storage tanks which are typically designed for 0.05 to 0.2 volume % boil-off per day. This is particularly critical in environmental sensitive markets where a stringent Wobbe Index must be met (e.g., California market). Viewed from a different perspective, contemplated configurations and methods provide operational flexibility by liquefying the boil-off gas at an optimum pressure while allowing a portion of the pressurized boil-off gas to be used as fuel gas to gas turbine power generator and/or routed to the boil-off gas recondenser which minimizes the reliquefaction power consumption during peak sendout operation.
[0029] Further known aspects, configurations, and methods suitable for use herein are described in our co-pending International patent application having publication number WO 2006/066015. This and all other extrinsic materials discussed herein are incorporated by reference in their entirety. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
[0030] Thus, specific embodiments and applications of LNG regasification plants with Wobbe index control have been disclosed. It should be apparent, however, to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms "comprises" and "comprising" should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refers to at least one of something selected from the group Attny DktNo. 100325.0330PCT
consisting of A, B, C .... and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc.

Claims

Attny DktNo. 100325.0330PCTCLAIMSWhat is claimed is:
1. A method of Wobbe index control of LNG in an LNG storage tank, comprising: fluidly coupling an LNG storage tank to a regasification unit such that the tank provides LNG to the regasification unit; fluidly coupling a compression unit to the LNG storage tank such that the tank provides cold boil-off gas to the compression unit, wherein the compression unit forms a compressed boil-off gas; heat-exchanging a first stream of the compressed boil-off gas using the cold boil-off gas to form cooled compressed boil-off gas, and combining a first portion of the cooled compressed boil-off gas with the LNG; reliquefying a second portion of the cooled compressed boil-off gas to form a reliquefied boil-off gas; separating nitrogen from the reliquefied boil-off gas to produce a lean reliquefied boil-off gas; and feeding the lean reliquefied boil-off gas into the LNG storage tank.
2. The method of claim 1 further comprising a step of feeding the combined cooled compressed boil-off gas and LNG into a recondenser upstream of the regasification unit.
3. The method of claim 1 wherein LNG provides refrigeration content for the step of reliquefying.
4. The method of claim 3 wherein the step of reliquefying comprises use of a cold box.
5. The method of claim 1 wherein the step of reliquefying comprises use of a cold box.
6. The method of claim 1 wherein the step of separating nitrogen from the reliquefied boil-off gas comprises a step of expanding the reliquefied boil-off gas in a JT valve or an expander and separating the expanded reliquefied boil-off gas in a separator.
7. The method of claim 4 wherein the nitrogen is combined with the cold boil-off gas.
8. The method of claim 1 further comprising a step of compressing a second stream of the compressed boil-off gas.
9. The method of claim 8 wherein the second stream of the compressed boil-off gas is fed to a combustor or utilized as fuel gas. Attny DktNo. 100325.0330PCT
10. The method of claim 1 further comprising a step of increasing a ratio between first and second portion when flow of the LNG to the regasifϊcation unit increases.
11. A LNG storage and regasifϊcation plant comprising: a LNG storage tank fiuidly coupled to a regasifϊcation unit to allow providing LNG from the tank to the regasifϊcation unit; a compression unit fiuidly coupled to the LNG storage tank to allow providing cold boil-off gas from the tank to the compression unit, wherein the compression unit is configured to form a compressed boil-off gas; a heat exchanger configured to allow cooling of a first stream of the compressed boil- off gas using the cold boil-off gas to so form a cooled compressed boil-off gas; a first conduit configured to allow combination of a first portion of the cooled compressed boil-off gas with the LNG; a cooler configured to allow reliquefaction of a second portion of the cooled compressed boil-off gas to form a reliquefied boil-off gas; a separator configured to allow separation of nitrogen from the reliquefied boil-off gas to so produce a lean reliquefied boil-off gas; and a second conduit configured to allow feeding the lean reliquefied boil-off gas into the
LNG storage tank.
12. The storage and regasification plant of claim 11 further comprising a recondenser upstream of the regasification unit hath is configured to receive the cooled compressed boil-off gas and the LNG.
13. The storage and regasification plant of claim 11 wherein the cooler is configured to employ refrigeration content from the LNG for the reliquefaction.
14. The storage and regasification plant of claim 13 wherein the cooler is a cold box.
15. The storage and regasification plant of claim 11 wherein the cooler is a cold box.
16. The storage and regasification plant of claim 11 further comprising an expansion device upstream of the separator and configured to at least partially expand the reliquefied boil-off gas.
17. The storage and regasification plant of claim 14 further comprising a third conduit that is configured to allow combination of the nitrogen with the cold boil-off gas. Attny DktNo. 100325.0330PCT
18. The storage and regasiflcation plant of claim 11 further comprising a compressor that is configured to allow compression of a second stream of the compressed boil-off gas.
19. The storage and regasification plant of claim 18 wherein the compressor is fluidly coupled to a combustor to allow feeding of the second stream from the compressor to the combustor.
20. The storage and regasification plant of claim 11 further comprising a flow control unit that is configured to allow increasing a ratio between the first and second portion when flow of the LNG to the regasification unit increases.
PCT/US2009/039740 2008-04-11 2009-04-07 Methods and configuration of boil-off gas handling in lng regasification terminals WO2009126604A1 (en)

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CA2718840A CA2718840A1 (en) 2008-04-11 2009-04-07 Methods and configuration of boil-off gas handling in lng regasification terminals
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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012016166A1 (en) * 2010-07-29 2012-02-02 Fluor Technologies Corporation Configurations and methods for small scale lng production
US8459241B2 (en) 2009-12-17 2013-06-11 Northstar, Inc. Liquefied natural gas system for a natural gas vehicle
WO2015036708A3 (en) * 2013-09-12 2016-03-03 Cryostar Sas Device for recovering vapours from a cryogenic tank
EP2685079A4 (en) * 2011-03-11 2016-07-13 Daewoo Shipbuilding & Marine Method for supplying fuel for high-pressure natural gas injection engine
WO2017159548A1 (en) * 2016-03-18 2017-09-21 三井造船株式会社 Boil-off gas processing system and liquefied gas transport vessel
EP2623414A4 (en) * 2010-09-30 2018-07-18 Mitsubishi Heavy Industries, Ltd. Boil-off gas reliquefaction device
US10364013B2 (en) 2015-06-02 2019-07-30 Daewoo Shipbuilding & Marine Engineering Co., Ltd. Ship
US10399655B2 (en) 2015-06-02 2019-09-03 Daewoo Shipbuilding & Marine Engineering Co., Ltd. Ship
US10995910B2 (en) 2015-07-13 2021-05-04 Technip France Process for expansion and storage of a flow of liquefied natural gas from a natural gas liquefaction plant, and associated plant
US11112173B2 (en) 2016-07-01 2021-09-07 Fluor Technologies Corporation Configurations and methods for small scale LNG production

Families Citing this family (40)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102010000946B4 (en) 2010-01-15 2022-12-15 Tge Marine Gas Engineering Gmbh Process and tank system for the liquefaction of boil-off gas
AU2011219783B2 (en) 2010-02-26 2015-06-04 Statoil Petroleum As Method for turndown of a liquefied natural gas (LNG) plant
US20120000242A1 (en) * 2010-04-22 2012-01-05 Baudat Ned P Method and apparatus for storing liquefied natural gas
US10451344B2 (en) 2010-12-23 2019-10-22 Fluor Technologies Corporation Ethane recovery and ethane rejection methods and configurations
US20140060110A1 (en) * 2011-03-11 2014-03-06 Daewoo Shipbuilding & Marine Engineering Co., Ltd. Fuel supply system for marine structure having reliquefaction apparatus and high-pressure natural gas injection engine
EP2693035A4 (en) * 2011-03-22 2016-07-13 Daewoo Shipbuilding&Marine Engineering Co Ltd Method and system for supplying fuel to high-pressure natural gas injection engine
KR101106088B1 (en) * 2011-03-22 2012-01-18 대우조선해양 주식회사 Non-flammable mixed refrigerant using for reliquifaction apparatus in system for supplying fuel for high pressure natural gas injection engine
US20140053600A1 (en) * 2011-03-22 2014-02-27 Daewoo Shipbuilding & Marine Engineering Co., Ltd. System for supplying fuel to high-pressure natural gas injection engine having excess evaporation gas consumption means
US9927068B2 (en) 2011-12-02 2018-03-27 Fluor Technologies Corporation LNG boiloff gas recondensation configurations and methods
KR101386543B1 (en) 2012-10-24 2014-04-18 대우조선해양 주식회사 System for treating boil-off gas for a ship
EP2746707B1 (en) * 2012-12-20 2017-05-17 Cryostar SAS Method and apparatus for reliquefying natural gas
KR101277965B1 (en) * 2013-02-19 2013-06-27 현대중공업 주식회사 A fuel gas supply system of liquefied natural gas
US20140318178A1 (en) * 2013-04-24 2014-10-30 GNC Galileo SA Method and apparatus for the liquefaction of natural gas
US20140352330A1 (en) * 2013-05-30 2014-12-04 Hyundai Heavy Industries Co., Ltd. Liquefied gas treatment system
KR101640768B1 (en) 2013-06-26 2016-07-29 대우조선해양 주식회사 Method for building a ship
US9982843B2 (en) * 2013-07-08 2018-05-29 The Boeing Company Systems and methods for maintaining pressure in cryogenic storage tanks
US10267457B2 (en) * 2013-09-27 2019-04-23 Excelerate Energy Limited Partnership Apparatus, system and method for the capture, utilization and sendout of latent heat in boil off gas onboard a cryogenic storage vessel
CN104482395B (en) * 2014-11-05 2016-05-18 中海福建天然气有限责任公司 A kind of method of BOG while utilizing LNG cold energy to reclaim tank car entrucking
CA2976071C (en) 2015-02-09 2020-10-27 Fluor Technologies Corporation Methods and configuration of an ngl recovery process for low pressure rich feed gas
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EP3274640B1 (en) * 2015-03-23 2024-08-14 Cool Science Inc. Industrial and hydrocarbon gas liquefaction
WO2016195231A1 (en) * 2015-06-02 2016-12-08 대우조선해양 주식회사 Ship
JP6609176B2 (en) * 2015-11-06 2019-11-20 川崎重工業株式会社 Ship
WO2017078154A1 (en) * 2015-11-06 2017-05-11 川崎重工業株式会社 Ship
US10006701B2 (en) 2016-01-05 2018-06-26 Fluor Technologies Corporation Ethane recovery or ethane rejection operation
EP3193017B1 (en) * 2016-01-18 2018-08-22 Cryostar SAS System for supplying compressed gas to several gas-fed devices
US10330382B2 (en) 2016-05-18 2019-06-25 Fluor Technologies Corporation Systems and methods for LNG production with propane and ethane recovery
US10605522B2 (en) * 2016-09-01 2020-03-31 Fluor Technologies Corporation Methods and configurations for LNG liquefaction
US11725879B2 (en) 2016-09-09 2023-08-15 Fluor Technologies Corporation Methods and configuration for retrofitting NGL plant for high ethane recovery
AU2017381785B2 (en) * 2016-12-23 2020-04-16 Shell Internationale Research Maatschappij B.V. Vessel for the transport of liquefied gas and method of operating the vessel
JP6347003B1 (en) * 2017-01-25 2018-06-20 デウ シップビルディング アンド マリン エンジニアリング カンパニー リミテッド LNG ship evaporative gas reliquefaction method and system
KR102066632B1 (en) * 2017-03-24 2020-01-15 대우조선해양 주식회사 BOG Re-liquefaction System and Method for Vessel
CA3077409A1 (en) 2017-10-20 2019-04-25 Fluor Technologies Corporation Phase implementation of natural gas liquid recovery plants
EP3517869A1 (en) * 2018-01-24 2019-07-31 Gas Technology Development Pte Ltd Process and system for reliquefying boil-off gas (bog)
IT201800008157A1 (en) * 2018-08-22 2020-02-22 Saipem Spa CRYOGENIC THERMODYNAMIC CYCLE WITH THERMAL RECOVERY
IT201800010171A1 (en) * 2018-11-08 2020-05-08 Saipem Spa PROCESS FOR THE RE-LIQUEFACTION AND CONTEMPORARY DECREASE OF THE NITROGEN CONTENT IN THE BOG FOR SELF-REFRIGERATED ABSORPTION
FR3089282B1 (en) * 2018-11-30 2023-02-24 Gaztransport Et Technigaz GAS TREATMENT SYSTEM OF A RECEPTION TERMINAL EQUIPPED WITH A REGASIFICATION UNIT AND CORRESPONDING GAS TREATMENT METHOD
US11719387B2 (en) * 2018-12-05 2023-08-08 Messer Industries Usa, Inc. Liquid conditioning for cryogen vessel fill station
US12098882B2 (en) 2018-12-13 2024-09-24 Fluor Technologies Corporation Heavy hydrocarbon and BTEX removal from pipeline gas to LNG liquefaction
CN110686463A (en) * 2019-07-05 2020-01-14 芜湖中燃城市燃气发展有限公司 Natural gas circulating refrigeration liquefaction device

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4017283A (en) * 1971-11-17 1977-04-12 Sulzer Brothers Limited Method and plant for making up nitrogen vaporization losses in nitrogen-containing liquified natural gas carrying tankers
US4675037A (en) * 1986-02-18 1987-06-23 Air Products And Chemicals, Inc. Apparatus and method for recovering liquefied natural gas vapor boiloff by reliquefying during startup or turndown

Family Cites Families (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3780534A (en) * 1969-07-22 1973-12-25 Airco Inc Liquefaction of natural gas with product used as absorber purge
GB1472533A (en) * 1973-06-27 1977-05-04 Petrocarbon Dev Ltd Reliquefaction of boil-off gas from a ships cargo of liquefied natural gas
MY117068A (en) * 1998-10-23 2004-04-30 Exxon Production Research Co Reliquefaction of pressurized boil-off from pressurized liquid natural gas
JP3676604B2 (en) * 1999-02-04 2005-07-27 株式会社神戸製鋼所 Intermediate medium type vaporizer and method of supplying natural gas using the vaporizer
GB0001801D0 (en) * 2000-01-26 2000-03-22 Cryostar France Sa Apparatus for reliquiefying compressed vapour
US6564579B1 (en) * 2002-05-13 2003-05-20 Black & Veatch Pritchard Inc. Method for vaporizing and recovery of natural gas liquids from liquefied natural gas
US7201002B1 (en) * 2003-04-21 2007-04-10 Cryogenic Group, Inc. Anti-weathering apparatus method for liquid and vapor storage systems
NO20035047D0 (en) * 2003-11-13 2003-11-13 Hamworthy Kse Gas Systems As Apparatus and method for temperature control of gas condensation
NO323496B1 (en) 2004-01-23 2007-05-29 Hamwrothy Kse Gas System As Process for recondensing decoction gas
US20060032239A1 (en) * 2004-08-12 2006-02-16 Chicago Bridge & Iron Company Boil-off gas removal system
WO2006031634A1 (en) 2004-09-13 2006-03-23 Argent Marine Operations, Inc System and process for transporting lng by non-self-propelled marine lng carrier
MX2007007021A (en) 2004-12-16 2007-08-14 Fluor Tech Corp Configurations and methods for lng regasification and btu control.
GB0501335D0 (en) * 2005-01-21 2005-03-02 Cryostar France Sa Natural gas supply method and apparatus
CN101421554B (en) 2006-04-13 2012-06-20 氟石科技公司 LNG vapor handling configurations and methods
US7493778B2 (en) * 2006-08-11 2009-02-24 Chicago Bridge & Iron Company Boil-off gas condensing assembly for use with liquid storage tanks
CN100424450C (en) * 2006-11-21 2008-10-08 华南理工大学 Method for using cooling capacity of LNG with cooling media as medium and apparatus thereof
US8028724B2 (en) * 2007-02-12 2011-10-04 Daewoo Shipbuilding & Marine Engineering Co., Ltd. LNG tank and unloading of LNG from the tank
EP2003389A3 (en) * 2007-06-15 2017-04-19 Daewoo Shipbuilding & Marine Engineering Co., Ltd Method and apparatus for treating boil-off gas in an LNG carrier having a reliquefaction plant, and LNG carrier having said apparatus for treating boil-off gas
KR101076266B1 (en) 2007-07-19 2011-10-26 대우조선해양 주식회사 System for supplying fuel gas in lng carrier

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4017283A (en) * 1971-11-17 1977-04-12 Sulzer Brothers Limited Method and plant for making up nitrogen vaporization losses in nitrogen-containing liquified natural gas carrying tankers
US4675037A (en) * 1986-02-18 1987-06-23 Air Products And Chemicals, Inc. Apparatus and method for recovering liquefied natural gas vapor boiloff by reliquefying during startup or turndown

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP2265854A4 *

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8459241B2 (en) 2009-12-17 2013-06-11 Northstar, Inc. Liquefied natural gas system for a natural gas vehicle
US9829244B2 (en) 2010-07-29 2017-11-28 Fluor Technologies Corporation Configurations and methods for small scale LNG production
CN103229011A (en) * 2010-07-29 2013-07-31 氟石科技公司 Configurations and methods for small scale lng production
CN103229011B (en) * 2010-07-29 2016-03-23 氟石科技公司 The configuration that small-sized LNG produces and method
EA026072B1 (en) * 2010-07-29 2017-02-28 Флуор Текнолоджиз Корпорейшн Plant and method for liquefied natural gas production
WO2012016166A1 (en) * 2010-07-29 2012-02-02 Fluor Technologies Corporation Configurations and methods for small scale lng production
EP2623414A4 (en) * 2010-09-30 2018-07-18 Mitsubishi Heavy Industries, Ltd. Boil-off gas reliquefaction device
EP2685079A4 (en) * 2011-03-11 2016-07-13 Daewoo Shipbuilding & Marine Method for supplying fuel for high-pressure natural gas injection engine
WO2015036708A3 (en) * 2013-09-12 2016-03-03 Cryostar Sas Device for recovering vapours from a cryogenic tank
US10399655B2 (en) 2015-06-02 2019-09-03 Daewoo Shipbuilding & Marine Engineering Co., Ltd. Ship
US10364013B2 (en) 2015-06-02 2019-07-30 Daewoo Shipbuilding & Marine Engineering Co., Ltd. Ship
US10654553B2 (en) 2015-06-02 2020-05-19 Daewoo Shipbuilding & Marine Engineering Co., Ltd. Ship with boil-off gas liquefaction system
US10661873B2 (en) 2015-06-02 2020-05-26 Daewoo Shipbuilding & Marine Engineering Co., Ltd. Ship
US10661874B2 (en) 2015-06-02 2020-05-26 Daewoo Shipbuilding & Marine Engineering Co., Ltd. Ship
US10995910B2 (en) 2015-07-13 2021-05-04 Technip France Process for expansion and storage of a flow of liquefied natural gas from a natural gas liquefaction plant, and associated plant
JP2017172603A (en) * 2016-03-18 2017-09-28 三井造船株式会社 Boil-off gas treatment system and liquefied gas carrying vessel
WO2017159548A1 (en) * 2016-03-18 2017-09-21 三井造船株式会社 Boil-off gas processing system and liquefied gas transport vessel
US11112173B2 (en) 2016-07-01 2021-09-07 Fluor Technologies Corporation Configurations and methods for small scale LNG production

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US8893515B2 (en) 2014-11-25
EP2265854A4 (en) 2017-11-15
CA2718840A1 (en) 2009-10-15
MX2010010706A (en) 2010-11-01
CN102084171B (en) 2012-10-10
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US20110056238A1 (en) 2011-03-10
EP2265854A1 (en) 2010-12-29

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