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WO2020012637A1 - Procédé de détermination de composition de fluide frigorigène mixte pour dispositif de liquéfaction de gaz naturel - Google Patents

Procédé de détermination de composition de fluide frigorigène mixte pour dispositif de liquéfaction de gaz naturel Download PDF

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Publication number
WO2020012637A1
WO2020012637A1 PCT/JP2018/026481 JP2018026481W WO2020012637A1 WO 2020012637 A1 WO2020012637 A1 WO 2020012637A1 JP 2018026481 W JP2018026481 W JP 2018026481W WO 2020012637 A1 WO2020012637 A1 WO 2020012637A1
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Prior art keywords
mixed refrigerant
natural gas
condition
composition
new
Prior art date
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Ceased
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PCT/JP2018/026481
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English (en)
Japanese (ja)
Inventor
汐崎　徹
恒男 渡辺
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Chiyoda Corp
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Chiyoda Corp
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Priority to PCT/JP2018/026481 priority Critical patent/WO2020012637A1/fr
Priority to JP2018559403A priority patent/JP6470482B1/ja
Publication of WO2020012637A1 publication Critical patent/WO2020012637A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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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
    • 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
    • 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
    • F25J1/0047—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
    • F25J1/0052—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 vaporising a liquid refrigerant 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
    • 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
    • F25J1/0047—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
    • F25J1/0052—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 vaporising a liquid refrigerant stream
    • F25J1/0055—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 vaporising a liquid refrigerant stream originating from an incorporated cascade
    • 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
    • F25J1/006—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the refrigerant fluid used
    • F25J1/008—Hydrocarbons
    • F25J1/0087—Propane; Propylene
    • 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
    • F25J1/02—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
    • F25J1/0211—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 a multi-component refrigerant [MCR] fluid in a closed vapor compression cycle
    • F25J1/0214—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 a multi-component refrigerant [MCR] fluid in a closed vapor compression cycle as a dual level refrigeration cascade with at least one MCR cycle
    • F25J1/0215—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 a multi-component refrigerant [MCR] fluid in a closed vapor compression cycle as a dual level refrigeration cascade with at least one MCR cycle with one SCR cycle
    • F25J1/0216—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 a multi-component refrigerant [MCR] fluid in a closed vapor compression cycle as a dual level refrigeration cascade with at least one MCR cycle with one SCR cycle using a C3 pre-cooling cycle
    • 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
    • F25J1/02—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
    • F25J1/0243—Start-up or control of the process; Details of the apparatus used; Details of the refrigerant compression system used
    • F25J1/0244—Operation; Control and regulation; Instrumentation
    • 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
    • F25J1/02—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
    • F25J1/0243—Start-up or control of the process; Details of the apparatus used; Details of the refrigerant compression system used
    • F25J1/0244—Operation; Control and regulation; Instrumentation
    • F25J1/0245—Different modes, i.e. 'runs', of operation; Process control
    • F25J1/0249—Controlling refrigerant inventory, i.e. composition or quantity

Definitions

  • the present invention relates to a method for determining the composition of a mixed refrigerant in a natural gas liquefier.
  • the natural gas (NG: Natural Gas) liquefaction system of the propane precooled mixed refrigerant system uses a mixed refrigerant so that the energy efficiency is maximized in the design stage, taking into account the composition and pressure of the raw material gas produced from the gas well.
  • the conditions such as the composition and flow rate are set.
  • the composition and pressure of the source gas change according to the remaining amount of the source gas in the gas well.
  • the gas well is switched, the composition and pressure of the source gas change. Therefore, there is a problem that the conditions set in the design stage deviate from the optimum conditions of the natural gas liquefaction apparatus, and the energy efficiency is reduced.
  • a simulation model of the natural gas liquefaction unit was created from the current operating conditions, a new supply condition changed from the current supply condition of the raw material gas was set in this simulation model, and simulation was performed.
  • There is a method of setting the composition of the mixed refrigerant when the power of the compressor for compressing the refrigerant becomes minimum as the optimum mixed refrigerant for example, Patent Document 1).
  • the UA value U: overall heat transfer coefficient [W / (m 2 ⁇ K)]
  • A Calculate the heat transfer area [m 2 ]
  • the simulation model is executed while adjusting the simulation model so that the UA value when the composition of the mixed refrigerant is changed is equal to the UA value calculated based on the current operating conditions.
  • the UA value calculated based on the current operating conditions is different from the UA value under the new supply conditions of the natural gas and the mixed refrigerant. . Therefore, if the simulation is performed based on the UA value calculated based on the current operating conditions, the accuracy of the simulation decreases, and it becomes difficult to find the optimum composition of the mixed refrigerant. As a result, the energy efficiency of the natural gas liquefier may not be maximized.
  • an object of the present invention is to improve the energy efficiency of a natural gas liquefaction apparatus in a method for determining a mixed refrigerant composition of a natural gas liquefaction apparatus.
  • one embodiment of the present invention provides a pre-cooling heat exchanger (3) for cooling natural gas and a mixed refrigerant with a pre-cooling refrigerant, and the natural gas cooled by the pre-cooling heat exchanger.
  • a method for determining a composition comprising: a model creation step (S1) for creating a simulation model of the natural gas liquefaction apparatus based on a first condition that is an operating condition of the natural gas liquefaction apparatus at a certain point in time; A UA0 calculating step (S2) of calculating a UA value, which is a value obtained by multiplying the overall heat transfer coefficient of the heat exchanger by a heat transfer area, as UA0 based on the simulation model and the first condition; On the basis of the new NG supply condition, which is a new supply condition of the natural gas, which is different from the natural gas supply condition, and the UA0, the natural gas supply condition in the first condition is changed to the new NG supply condition.
  • the UA value expected under the third condition including the supply condition and the candidate composition is calculated as UA2, and the third UA value is calculated.
  • a composition determining step (S6) of determining a new composition of the refrigerant
  • the UA value (UA2) according to the new supply conditions of the natural gas and the mixed refrigerant is calculated, and the simulation is executed based on the UA value, so that the accuracy of the simulation is improved.
  • the energy efficiency of the natural gas liquefaction apparatus can be improved.
  • the power estimation step includes executing a simulation using the simulation model based on the new NG supply condition, the candidate composition, and the UA1 for each of the candidate compositions, A first step (S11) of calculating a new supply condition of the mixed refrigerant, and a second step (S11) of calculating a temporary UA2 based on the UA1 and the new supply condition of the mixed refrigerant calculated in the first step ( S12), replacing the UA1 with the latest temporary UA2, repeatedly executing the first step and the second step, and converging the temporary UA2, and the temporary step converged in the third step.
  • UA2 is determined as the UA2, and the supply condition of the mixed refrigerant, the new NG supply condition, and the candidate when the UA2 is calculated.
  • Determining the third condition comprising growth it may have a fourth step (S14) and for calculating the total power consumption of the plurality of the compressor by using the simulation model based on the third condition.
  • the UA value is corrected based on the condition of the mixed refrigerant, and becomes the UA value according to the new condition of the mixed refrigerant.
  • the second step uses the UA2 calculation function (f2) defined based on a relationship between the UA value and the mass flow rate of the mixed refrigerant, and calculates the UA1 and the UA1 in the first step.
  • the temporary UA2 may be calculated based on the new supply condition of the mixed refrigerant.
  • the UA2 calculation function may be a function defined based on the UA value, the mass flow rate of the mixed refrigerant, and the physical property value of the mixed refrigerant.
  • the UA value can be corrected based on the condition of the mixed refrigerant.
  • the UA1 calculation step uses a UA1 calculation function (f1) defined based on a relationship between the UA value and the mass flow rate of the natural gas, and sets the UA0 and the second condition to be equal to each other.
  • the UA1 may be calculated based on the UA1.
  • the UA1 calculation function may be a function defined based on a relationship between the UA value, the mass flow rate of the natural gas, and the physical property value of the natural gas.
  • the UA value can be corrected based on the conditions of natural gas.
  • the energy efficiency of the natural gas liquefier can be improved.
  • Configuration diagram of the natural gas liquefaction apparatus according to the embodiment Configuration diagram of pre-cooling heat exchanger Flow chart showing the procedure of the mixed refrigerant composition determination process Flow chart showing the procedure of the power estimation step (S5) of the mixed refrigerant composition determination processing
  • the natural gas liquefaction apparatus 1 liquefies natural gas produced from a gas field and purified through a purification apparatus 2.
  • Natural gas produced from gas wells contains about 80-98 mol% of methane, hydrocarbons such as ethane, propane, butane, nitrogen, and other impurities.
  • the composition and pressure of the natural gas produced varies depending on the characteristics and remaining amount of each gas well.
  • the refining device 2 is a condensate removing device for removing liquid hydrocarbons from natural gas, a mercury removing device for removing mercury from natural gas, and an acid gas for removing acidic gases such as H 2 S, CO 2 and organic sulfur from natural gas. It includes a removal device, a dehydration device for removing moisture from natural gas, a distillation device for separating heavy components from natural gas, and the like.
  • the natural gas liquefaction apparatus 1 is cooled by a pre-cooling heat exchanger (C3 cooling circuit) 3 for cooling purified natural gas and a mixed refrigerant by a pre-cooling refrigerant, and a pre-cooling heat exchanger 3.
  • C3 cooling circuit for cooling purified natural gas and a mixed refrigerant by a pre-cooling refrigerant
  • a pre-cooling heat exchanger 3 for cooling purified natural gas and a mixed refrigerant by a pre-cooling refrigerant
  • a pre-cooling heat exchanger 3 for cooling purified natural gas and a mixed refrigerant by a pre-cooling refrigerant
  • a pre-cooling heat exchanger 3 for cooling purified natural gas and a mixed refrigerant by a pre-cooling refrigerant
  • pre-cooling heat exchanger 3 for cooling purified natural gas and a mixed refrigerant by a pre-cooling refrigerant
  • MCHE cryogenic heat exchanger 4
  • the mixed refrigerant contains at least two selected from nitrogen and hydrocarbons having 1 to 3 carbon atoms (methane, ethane, propane, etc.).
  • the mixed refrigerant includes four of nitrogen, methane (C1), ethane (C2), and propane (C3).
  • the composition (mixing ratio) of the mixed refrigerant can be arbitrarily changed.
  • the pre-cooling refrigerant mainly contains propane.
  • Natural gas purified by the refining device 2 is supplied to the pre-cooling heat exchanger 3 by the line L1.
  • the pre-cooling heat exchanger 3 includes first to third pre-cooling heat exchangers 3A, 3B and 3C connected in series, and fourth to sixth pre-cooling heat exchangers 3D connected in series. , 3E, 3F, a line L2 in which natural gas flows, a line L3 in which mixed refrigerant flows, and a line L4 in which precooling refrigerant flows.
  • the line L4 branches into a line L4A sequentially passing through the first to third precooling heat exchangers 3A, 3B and 3C and a line L4B sequentially passing through the fourth to sixth precooling heat exchangers 3D, 3E and 3F. .
  • the line L2 through which natural gas flows passes through the first to third precooling heat exchangers 3A to 3C in order.
  • the line L3 through which the mixed refrigerant gas flows sequentially passes through the fourth to sixth pre-cooling heat exchangers 3D to 3F.
  • first precooling heat exchanger 3A In the line L4A, an upstream portion of the first precooling heat exchanger 3A, a portion between the first precooling heat exchanger 3A and the second precooling heat exchanger 3B, a second precooling heat exchanger 3B and a third precooling heat exchanger.
  • the first to third expansion valves 11A, 11B, 11C are provided in each of the portions between 3C. Each time the pre-cooling refrigerant passes through the first to third expansion valves 11A, 11B, 11C, it expands to lower the pressure and the temperature.
  • an upstream portion of the fourth pre-cooling heat exchanger 3D, a portion between the fourth pre-cooling heat exchanger 3D and the fifth pre-cooling heat exchanger 3E, a fifth pre-cooling heat exchanger 3E and a sixth pre-cooling heat Fourth to sixth expansion valves 11D, 11E, 11F are provided in the respective portions between the exchangers 3F.
  • the precooling refrigerant passes through the fourth to sixth expansion valves 11D, 11E, and 11F, it expands to lower the pressure and the temperature.
  • the first pre-cooling heat exchanger 3A is provided with a first pre-cooling refrigerant outlet
  • the second pre-cooling heat exchanger 3B is provided with a second pre-cooling refrigerant outlet.
  • the third precooling heat exchanger 3C is provided with a third precooling refrigerant outlet. Part of the pre-cooling refrigerant that has passed through the first pre-cooling heat exchanger 3A flows through the second expansion valve 11B to the second pre-cooling heat exchanger 3B, and the rest flows to the first pre-cooling refrigerant outlet.
  • Part of the pre-cooling refrigerant that has passed through the second pre-cooling heat exchanger 3B flows through the third expansion valve 11C, flows into the third pre-cooling heat exchanger 3C, and the rest flows through the second pre-cooling refrigerant outlet. All of the pre-cooling refrigerant that has passed through the third pre-cooling heat exchanger 3C flows to the third pre-cooling refrigerant outlet.
  • the natural gas that has passed through the refining device 2 passes through the first to third precooling heat exchangers 3A to 3C in the order described, and is cooled to about ⁇ 30 ° C. by the precooling refrigerant.
  • the mixed refrigerant passes through the fourth to sixth precooling heat exchangers 3D to 3F in the order described, and is cooled to about ⁇ 30 ° C. by the precooling refrigerant.
  • each of the first to third pre-cooling refrigerant outlets is connected to the suction port of the corresponding pressure stage of the first compressor 6 via lines L6, L7, L8.
  • the first compressor 6 has, for example, a gas turbine, an electric motor, a steam turbine, or the like as a drive source.
  • the fourth pre-cooling heat exchanger 3D is provided with a fourth pre-cooling refrigerant outlet
  • the fifth pre-cooling heat exchanger 3E is provided with a fifth pre-cooling refrigerant outlet.
  • the sixth precooling heat exchanger 3F is provided with a sixth precooling refrigerant outlet. Part of the pre-cooling refrigerant that has passed through the fourth pre-cooling heat exchanger 3D passes through the fifth expansion valve 11E, flows into the fifth pre-cooling heat exchanger 3E, and the remainder flows through the fourth pre-cooling refrigerant outlet.
  • Part of the pre-cooling refrigerant that has passed through the fifth pre-cooling heat exchanger 3E passes through the fifth expansion valve 11F, flows into the sixth pre-cooling heat exchanger 3F, and the remainder flows through the fifth pre-cooling refrigerant outlet. All of the pre-cooling refrigerant that has passed through the sixth pre-cooling heat exchanger 3F flows to the sixth pre-cooling refrigerant outlet.
  • the fourth precooling refrigerant outlet is connected to line L6, the fifth precooling refrigerant outlet is connected to line L7, and the sixth precooling refrigerant outlet is connected to line L8.
  • the discharge port of the first compressor 6 is connected to the inlet of the precooling heat exchanger 3 (the first precooling heat exchanger 3A and the fourth precooling heat exchanger 3D) via the line L10.
  • a first cooler 14, a second cooler 15, and a third cooler 16 are sequentially provided from the first compressor 6 side.
  • the first cooler 14, the second cooler 15, and the third cooler 16 are, for example, air-cooled heat exchangers.
  • the pre-cooling refrigerant compressed by the first compressor 6 is condensed by the first cooler 14 and the second cooler 15 and is supercooled by the third cooler 16 before being supplied to the pre-cooling heat exchanger 3.
  • the cryogenic heat exchanger 4 is a spool-wound heat exchanger in which a bundle of heat transfer tubes, through which natural gas and a mixed refrigerant flows, is housed in a shell 17 in a coiled state.
  • a mixed refrigerant of liquid supplied from first and second spray headers 18 and 19 described later flows toward the bottom of the tower.
  • the cryogenic heat exchanger 4 has a warm-temperature region and a cool-temperature region in order from the bottom to the top of the tower, and the temperature decreases from the bottom to the top.
  • the heat transfer tubes in the shell 17 include a first heat transfer tube 21 through which natural gas flows, and second and third heat transfer tubes 22 and 23 through which mixed refrigerant flows.
  • the line L11 for supplying natural gas to the cryogenic heat exchanger 4 is connected to the lower end of the first heat transfer tube 21 at the bottom of the cryogenic heat exchanger 4.
  • the first heat transfer tube 21 extends from the bottom of the cryogenic heat exchanger 4 to the top.
  • the natural gas is liquefied and supercooled in the first heat transfer tube 21.
  • the upper end of the first heat transfer tube 21 is connected to a storage LNG tank (not shown) via a line L13 including a seventh expansion valve 26.
  • the natural gas liquefied in the first heat transfer tube 21 is expanded in the seventh expansion valve 26 to flush nitrogen and light components, and then sent to the LNG tank.
  • the temperature of the natural gas (LNG) after passing through the seventh expansion valve 26 is about -150 to 160 ° C.
  • the high-pressure mixed refrigerant partially liquefied by the precooling heat exchanger 3 is supplied to the refrigerant separator 28 via the line L15.
  • the refrigerant separator 28 separates the mixed refrigerant into a gas and a liquid.
  • the liquid mixed refrigerant separated in the refrigerant separator 28 is supplied to the lower end of the second heat transfer tube 22 via a line L16 connecting the refrigerant separator 28 and the second heat transfer tube 22.
  • the second heat transfer tube 22 extends from the bottom of the cryogenic heat exchanger 4 to the warm / hot region.
  • the upper end of the second heat transfer tube 22 is connected to the first spray header 18 via a line L17 provided with an eighth expansion valve 29.
  • the liquid mixed refrigerant flows upward in the second heat transfer tube 22, and then expands in the eighth expansion valve 29, and a part of the refrigerant is flash evaporated.
  • the mixed refrigerant that has passed through the eighth expansion valve 29 is discharged downward from the first spray header 18 (that is, so as to be countercurrent to the flow of the raw material gas in the cryogenic heat exchanger 4).
  • the mixed refrigerant discharged from the first spray header 18 flows downward while exchanging heat with the natural gas and the mixed refrigerant flowing in the first to third heat transfer tubes 21 to 23.
  • the gaseous mixed refrigerant separated in the refrigerant separator 28 is supplied to the lower end of the third heat transfer tube 23 via a line L19 connecting the refrigerant separator 28 and the third heat transfer tube 23.
  • the third heat transfer tube 23 extends from the column bottom of the cryogenic heat exchanger 4 to the cold / hot region.
  • the upper end of the third heat transfer tube 23 is connected to the second spray header 19 via a line L21 provided with a ninth expansion valve 31.
  • the liquid phase component of the mixed refrigerant flows upward in the third heat transfer tube 23, and then expands in the ninth expansion valve 31, and a part thereof flash evaporates.
  • the mixed refrigerant that has passed through the ninth expansion valve 31 is lower than the temperature of the natural gas (LNG) before passing through the seventh expansion valve 26, and is directed downward (ie, from the second spray header 19 disposed above the cold region). Is discharged so as to be countercurrent to the flow of the raw material gas in the cryogenic heat exchanger 4).
  • the mixed refrigerant discharged from the second spray header 19 flows downward while exchanging heat with the upper tube bundle formed by the first and third heat transfer tubes 21 and 23 arranged in the cold / hot region. Thereafter, the mixed refrigerant discharged from the second spray header 19 mixes with the mixed refrigerant discharged from the first spray header 18 located below, and then exchanges heat with the first to third heat transfer tubes 21 to 23. While flowing downward.
  • the mixed refrigerant discharged from the first and second spray headers 18 and 19 into the cryogenic heat exchanger 4 is discharged from the bottom of the cryogenic heat exchanger 4 as a low-pressure mixed refrigerant gas.
  • the low-pressure mixed refrigerant is, for example, ⁇ 40 ° C. and a pressure of 3.5 bara.
  • the outlet of the mixed refrigerant provided at the bottom of the cryogenic heat exchanger 4 is connected to the inlet of the second compressor 7 via a line L23.
  • the discharge port of the second compressor 7 is connected to the suction port of the third compressor 8 via a line L24.
  • the second and third compressors 7 and 8 have a drive unit such as a gas turbine, an electric motor, and a steam turbine.
  • the discharge port of the third compressor is connected to a line L3 of the precooling heat exchanger 3 via a line L25.
  • the line L24 is provided with a third cooler 35
  • the line L25 is provided with a fourth cooler 36.
  • the third cooler 35 and the fourth cooler 36 may be, for example, air-cooled heat exchangers.
  • the low-pressure gas mixed refrigerant discharged from the bottom of the cryogenic heat exchanger 4 is pressurized in the second compressor 7, cooled in the third cooler 35, pressurized in the third compressor 8, and cooled in the fourth compressor. It is cooled in the unit 36 and supplied to the pre-cooling heat exchanger 3.
  • the mixed refrigerant is cooled by the pre-cooling refrigerant in the pre-cooling heat exchanger 3 and partially liquefied, and then supplied to the refrigerant separator 28 again via the line L15.
  • a raw material replenishment line L28 for replenishing the mixed refrigerant is connected to a portion of the line L23 between the cryogenic heat exchanger 4 and the second compressor 7.
  • the source of supply of nitrogen (N 2 ), methane (C1), ethane (C2), and propane (C3) constituting the mixed refrigerant is connected to the raw material replenishment line L28.
  • Replenishment amount control valves 41 to 44 are provided between each supply source and the raw material replenishment line L28. By changing the opening degree of the replenishment amount control valves 41 to 44, the replenishment amount of each refrigerant composition from each supply source to the raw material replenishment line L28 can be adjusted.
  • a first extraction line L31 for extracting a liquid mixed refrigerant to the outside is connected to a line L16 connecting the refrigerant separator 28 and the second heat transfer tube 22.
  • a second extraction line L32 for extracting a gaseous mixed refrigerant to the outside is connected to a line L19 connecting the refrigerant separator 28 and the third heat transfer tube 23.
  • the first extraction line L31 and the second extraction line L32 are provided with extraction amount adjustment valves 46 and 47, respectively. By adjusting the degree of opening of the extraction amount control valves 46 and 47, the extraction amount of the refrigerant mixture of liquid and gas can be adjusted.
  • replenishment amount control valves 41 to 44 and the withdrawal amount control valves 46 and 47 it is possible to adjust the composition of the mixed refrigerant and the amount of refrigerant (inventory) in the system which is a factor for determining the pressure. .
  • the natural gas liquefaction apparatus 1 has thermometers T1 to T14 for measuring the temperatures of the natural gas, the mixed refrigerant, and the pre-cooling refrigerant, and the pressure gauges P1 to P1, which measure the pressures of the natural gas, the mixed refrigerant, and the pre-cooling refrigerant.
  • thermometers T1 to T14 for measuring the temperatures of the natural gas, the mixed refrigerant, and the pre-cooling refrigerant
  • the pressure gauges P1 to P1 which measure the pressures of the natural gas, the mixed refrigerant, and the pre-cooling refrigerant.
  • flow meters F1 to F8 for measuring the flow rates of the natural gas, the mixed refrigerant and the pre-cooling refrigerant
  • composition analyzers C1 and C2 for measuring the compositions of the natural gas and the mixed refrigerant are provided.
  • thermometer T1 is the temperature of the natural gas inside the line L11
  • thermometer T2 is the temperature of the natural gas inside the first heat transfer tube 21 in the warm / hot region
  • thermometer T3 is the temperature of the natural gas inside the first heat transfer tube 21 in the cold / hot region.
  • thermometer T4 is the temperature of the natural gas inside the line L13
  • thermometer T5 is the temperature of the mixed refrigerant inside the shell 17 in the warm / hot area
  • thermometer T6 is the temperature of the mixed refrigerant inside the shell 17 in the cold / hot area
  • Thermometer T7 is the temperature of the mixed refrigerant inside line L15
  • thermometer T8 is the temperature of the mixed refrigerant inside line L17
  • thermometer T9 is the temperature of the mixed refrigerant inside line L21
  • thermometer T10 is the temperature of the mixed refrigerant inside line L23.
  • Temperature, thermometer T11 is the temperature of the pre-cooling refrigerant inside line L6 (see FIG.
  • thermometer T12 is the temperature of the pre-cooling refrigerant inside line L7 (see FIG. 2)
  • thermometer T13 is In L8 internal temperature of refrigerant pre-cooling (see FIG. 2)
  • thermometer T14 measures the temperature of the pre-cooling refrigerant internal line L10.
  • the pressure gauge P1 is the pressure of the natural gas inside the line L1
  • the pressure gauge P2 is the pressure of the natural gas inside the line L11
  • the pressure gauge P3 is the pressure of the natural gas inside the line L13
  • the pressure gauge P4 is the pressure of the mixed refrigerant inside the line L15.
  • Pressure is the pressure of the mixed refrigerant inside line L23
  • pressure gauge P6 is the pressure of the pre-cooling refrigerant inside line L6 (see FIG. 2)
  • pressure gauge P7 is the pressure of the pre-cooling refrigerant inside line L7 (FIG. 2).
  • Pressure gauge P8 measures the pressure of the pre-cooling refrigerant inside the line L8, and the pressure gauge P9 measures the pressure of the pre-cooling refrigerant inside the line L10 (see FIG. 2).
  • the flow meter F1 is the flow rate of the natural gas inside the line L11
  • the flow meter F2 is the flow rate of the natural gas inside the line L13
  • the flow meter F3 is the flow rate of the mixed refrigerant inside the line L17
  • the flow meter F4 is the flow rate of the mixed refrigerant inside the line L21.
  • the flow rate, the flow meter F5 is the flow rate of the mixed refrigerant in the line L23
  • the flow meter F6 is the flow rate of the pre-cooling refrigerant in the line L6 (see FIG. 2)
  • the flow meter F7 is the flow rate of the pre-cooling refrigerant in the line L7 (FIG.
  • the flow meter F8 measures the flow rate (see FIG. 2) of the pre-cooling refrigerant inside the line L8.
  • the composition analyzer C1 measures the composition of the natural gas inside the line L1
  • the composition analyzer C2 measures the composition of the mixed refrigerant inside the line L24.
  • the thermometers T1 to T14, the pressure gauges P1 to P9, the flow meters F1 to F8, and the composition analyzers C1 and C2 output signals according to the measured values to the control device 50 (CU).
  • the control device 50 is an electronic control device having a CPU, a memory, a storage device storing programs, and the like.
  • the control device 50 includes first to third compressors 6 to 8, first to sixth expansion valves 11A to 11F, 26, 29, 31, replenishment amount control valves 41 to 44, and extraction amount control valves 46, 47. Control.
  • the arithmetic device 60 includes a CPU, a memory, a storage device that stores a program, and the like.
  • the arithmetic unit 60 acquires information about the temperature, pressure, and flow rate of the natural gas, the mixed refrigerant, and the pre-cooling refrigerant of the natural gas liquefaction apparatus 1 and the composition of the natural gas and the mixed refrigerant from the control device 50.
  • computing device 60 may obtain these information by other means, including manual input, or may include thermometers T1-T14, pressure gauges P1-P9, flow meters F1-F8, and It may be obtained directly from the composition analyzers C1 and C2.
  • the arithmetic unit 60 determines the mixed refrigerant composition suitable for the new natural gas supply condition by executing the mixed refrigerant composition determination process.
  • the mixed refrigerant composition suitable for the new natural gas supply condition refers to a mixed refrigerant composition that minimizes the total power consumption of the compressors 6, 7, and 8 in total.
  • the control device 50 may control the replenishment amount adjustment valves 41 to 44 and the extraction amount adjustment valves 46 and 47 at a certain timing based on the mixed refrigerant composition determined by the arithmetic device 60.
  • the arithmetic unit 60 creates a simulation model of the natural gas liquefaction apparatus 1 based on the first condition that is the operating condition of the natural gas liquefaction apparatus 1 at a certain point in time (S1: model creation step).
  • the operating conditions included in the first condition include natural gas, mixed refrigerant, and precooling detected by the thermometers T1 to T14, the pressure gauges P1 to P9, the flow meters F1 to F8, the composition analyzers C1 and C2. Including the temperature, pressure, flow rate, and composition of the refrigerant.
  • the operating condition at a certain time may be, for example, the operating condition at the time when the mixed refrigerant composition determination process is started.
  • the operating condition may be an instantaneous value of the operating condition at a certain point in time or an average value of operating conditions in a predetermined period in the past from a certain point in time.
  • the simulation model of the natural gas liquefaction apparatus 1 includes equipment such as heat exchange in the pre-cooling heat exchanger 3 and the cryogenic heat exchanger 4, and compression of the mixed refrigerant and the pre-cooling refrigerant in the first to third compressors 6, 7, and 8. It can be created using a known process simulator capable of expressing a unit operation executed in the natural gas liquefaction apparatus 1 every time.
  • the simulation model includes the supply composition of natural gas, the supply pressure, the supply temperature, the pressure and temperature of the natural gas and the mixed refrigerant in the cryogenic heat exchanger 4, the composition of the mixed refrigerant, the flow rate, the pressure, the temperature, and the flow rate of the pre-cooling refrigerant.
  • Pressure and temperature operating conditions can be entered. These operation conditions are set based on the current operation data of the natural gas liquefaction apparatus 1.
  • the UA value which is a value obtained by multiplying the overall heat transfer coefficient [W / (m 2 ⁇ K)] of the cryogenic heat exchanger 4 by the heat transfer area [m 2 ] is obtained.
  • the power consumed by the first to third compressors 6, 7, 8 can be calculated.
  • a simulation based on a simulation model is used to calculate the heat transfer amount Q in the cryogenic heat exchanger 4 and the temperature inside the cryogenic heat exchanger 4 based on the flow rate, temperature, and pressure of natural gas, mixed refrigerant, and precooling refrigerant.
  • the average logarithmic temperature difference ⁇ T obtained from the distribution and the power consumption of the first to third compressors 6, 7, 8 can be calculated.
  • the arithmetic unit 60 executes a simulation based on the simulation model and the first condition, and calculates UA0 as a UA value (S2: UA0 calculation step).
  • the arithmetic unit 60 determines the natural gas supply condition in the first condition based on the new NG supply condition, which is a new natural gas supply condition different from the first condition natural gas supply condition, and UA0.
  • the UA value expected under the second condition changed to the new NG supply condition is calculated as UA1 (S3: UA1 calculation step).
  • the new NG supply condition is different from the first condition in at least one of the supply composition and the supply pressure of the natural gas.
  • the new NG supply condition may be set to, for example, a natural gas supply condition expected in the gas well after switching.
  • the operator may manually input the new NG supply condition, or the arithmetic unit 60 may set the new NG supply condition based on a signal from a composition sensor or a pressure sensor provided in the gas well after switching.
  • the arithmetic unit 60 calculates UA1 from UA0 and the second condition based on a function f1 that defines the relationship between UA0 corresponding to the first condition and UA1 corresponding to the second condition.
  • the function f1 is, for example, a function defined based on the relationship between the UA value and the mass flow rate of the natural gas, and at least one of the physical property value and the Reynolds number of the natural gas, the UA value, and the mass flow rate of the natural gas. It may be a function or the like defined based on the relationship.
  • the physical property value of the natural gas includes at least one of the Prandtl number and the thermal conductivity.
  • the function f1 may be a function that calculates UA1 based on UA0, the mass flow rate of natural gas, Reynolds number, Prandtl number, and thermal conductivity. Further, the function f1 may be an empirical formula obtained by measuring a change in the UA value when the supply condition of the natural gas is changed.
  • the arithmetic unit 60 creates a plurality of mixed refrigerant composition candidates different from the mixed refrigerant composition under the first condition as candidate compositions (S4: candidate composition creating step).
  • candidate composition a plurality of sets in which the components of nitrogen, methane, ethane, and propane are randomly changed within a predetermined range based on the mixed refrigerant composition under the first condition are created.
  • the arithmetic unit 60 then performs a simulation using a simulation model based on the new NG supply condition, the candidate composition, and UA1 for each of the candidate compositions, thereby including the new NG supply condition and the candidate composition.
  • the UA value expected under the third condition is calculated as UA2, and the total power consumption of the plurality of compressors 6, 7, 8 is calculated for each of the third conditions (S5: power estimation process). The details of the power estimation step S5 are shown in the flowchart of FIG.
  • the arithmetic unit 60 executes the processing shown in FIG. 4 for each of the candidate compositions in the power trial calculation step (S5).
  • the arithmetic unit 60 calculates a new supply condition of the mixed refrigerant by executing a simulation using a simulation model based on the new NG supply condition, the candidate composition, and the UA1 (S11).
  • a new NG supply condition is input as a precondition for a new NG supply condition as a natural gas supply condition, a candidate composition as a mixed refrigerant composition, and a UA value as a UA value of the cryogenic heat exchanger 4, and a new mixed refrigerant supply is performed. Calculate the condition.
  • the new supply conditions of the mixed refrigerant include the pressure and the flow rate of the mixed refrigerant.
  • the temperature of the liquid natural gas to be produced (the temperature of the natural gas upstream of the seventh expansion valve 26 in the line L13) is set as a precondition.
  • the arithmetic unit 60 calculates the temporary UA2 based on the UA1 and the new supply condition of the mixed refrigerant calculated in the step S11 (S12).
  • the temporary UA2 is an expected UA value when the natural gas supply condition is the new NG supply condition and the mixed refrigerant is the candidate composition and the new supply condition calculated in step S11.
  • the arithmetic unit 60 mixes the UA1 with the UA1 based on a function f2 that defines the relationship between the UA1 corresponding to the second condition and the temporary UA2 corresponding to a condition in which the composition and the supply condition of the mixed refrigerant are changed from the second condition.
  • the temporary UA2 is calculated from the refrigerant supply conditions.
  • the function f2 is, for example, a function defined based on the relationship between the UA value and the mass flow rate of the mixed refrigerant, at least one of the physical property value and the Reynolds number of the mixed refrigerant, the UA value, and the mass flow rate of the mixed refrigerant. It may be a function or the like defined based on the relationship.
  • the physical property value of the mixed refrigerant includes at least one of the Prandtl number and the thermal conductivity.
  • the function f2 may be a function that calculates UA2 based on UA1, the mass flow rate of the mixed refrigerant, the Reynolds number, the Prandtl number, and the thermal conductivity.
  • the function f2 may be an empirical formula obtained by measuring a change in the UA value when the supply condition of the mixed refrigerant is changed.
  • the arithmetic unit 60 determines whether or not the value of the temporary UA2 has converged (S13).
  • the determination in S13 may be made to determine that the temporary UA2 has converged, for example, when the difference between the latest value of the temporary UA2 and the previous value of the temporary UA2 is equal to or smaller than a predetermined determination value. Further, when the rate of change of the latest value of temporary UA2 with respect to the previous value of temporary UA2 is equal to or less than a predetermined determination value, it may be determined that temporary UA2 has converged.
  • the temporary UA2 is calculated a plurality of times by repeating steps S11 and S12. At the first execution of step S13, since the previous value of temporary UA2 does not exist, the determination is made using UA1 instead of the previous value of temporary UA2.
  • step S13 If the determination result in step S13 is No, that is, if the value of the temporary UA2 has not converged, the process returns to step S11, and the processes in steps S11 and S12 are executed again. At this time, the process of step S11 is executed by replacing UA1 with the latest temporary UA2 calculated in step S12. The temporary UA2 converges by repeatedly executing the processing of steps S11 to S13.
  • the arithmetic device 60 determines the latest value of the temporary UA2 as UA2, and includes the mixed refrigerant supply condition, the new NG supply condition, and the candidate composition when UA2 was calculated.
  • the three conditions are determined, and the total power consumption of the plurality of compressors 6, 7, 8 is calculated using the simulation model based on the third condition (S14).
  • the power consumption of each of the first to third compressors 6, 7, and 8 is calculated based on the temperature, pressure, flow rate, and composition of the suction port and discharge port of each compressor. Calculate power consumption.
  • step S11 by executing a simulation using a simulation model based on the new NG supply condition, the candidate composition, and the UA1, the first to third compressors 6, 7 together with the new mixed refrigerant supply condition are executed. , 8 may be calculated in advance, and the total power consumption of the first to third compressors 6, 7, 8 corresponding to the third condition may be read in step S14.
  • the arithmetic unit 60 executes the processes of steps S11 to S14 for each of the candidate compositions, and calculates the total power consumption of the compressors 6, 7, and 8 for each of the candidate compositions. Thereby, the arithmetic unit 60 ends the power trial calculation process.
  • step S6 of FIG. 3 the arithmetic unit 60 determines a candidate composition having the smallest total power consumption among the plurality of candidate compositions as a new composition of the mixed refrigerant (composition determining step).
  • the arithmetic unit 60 may input the determined new composition of the mixed refrigerant to the control device 50.
  • the control device 50 may control each valve and each of the compressors 6, 7, 8 based on the new composition of the mixed refrigerant received from the arithmetic device 60.
  • the natural gas supplied to the natural gas liquefaction apparatus 1 is assumed to be lighter and lower in pressure from operating conditions (first condition, average molecular weight of natural gas 18.4 kg / kmol, supply pressure of natural gas 60 bar). Under the conditions (average molecular weight of natural gas 17.3 kg / kmol, natural gas supply pressure 50 bar), the composition of the mixed refrigerant that minimized the total power consumption of the compressor was determined.
  • the UA value used in the simulation was fixed to UA0 calculated based on the operating condition (first condition). More specifically, in the comparative example, UA0 is calculated by executing steps S1 and S2 in the mixed refrigerant composition determination process as in the example. The UA value is fixed to UA0 without executing step S3. Thereafter, similarly to step S4, a plurality of candidate compositions of the mixed refrigerant are created, and a simulation is performed for each of the candidate compositions using a simulation model based on the new NG supply condition, the candidate composition, and UA0. Thus, the total power consumption of each compressor is calculated.
  • the candidate composition having the smallest total power consumption is determined as the new composition of the mixed refrigerant. That is, in the comparative example, the UA value is not corrected based on the new NG supply condition and the new supply condition of the mixed refrigerant.
  • the mixed refrigerant was a mixture of N 2 , C1 (methane), C2 (ethane), and C3 (propane).
  • the following table shows the results of simulations of the example and the comparative example under virtual conditions.
  • the composition of the mixed refrigerant is represented by an average molecular weight as a general index.
  • the composition of the mixed refrigerant that maximizes the energy efficiency can be determined.
  • the UA value (UA2) according to the new supply condition of the natural gas and the mixed refrigerant is calculated, and the simulation is performed based on the UA value, so that the accuracy of the simulation is improved.
  • U UA0 calculated based on actual operation data is corrected based on new natural gas supply conditions (new NG supply conditions), and further corrected based on new conditions of mixed refrigerant, and becomes UA2.
  • new natural gas supply conditions new NG supply conditions
  • new conditions of mixed refrigerant new conditions of mixed refrigerant
  • the function f1 and the function f2 described above may be one common function f3.
  • the function f3 is, for example, a function defined based on the relationship between the UA value, the mass flow rate of the natural gas, and the mass flow rate of the mixed refrigerant, the UA value, the mass flow rate of the natural gas, and the physical property value of the natural gas. And a function defined based on a relationship between at least one of Reynolds, the mass flow rate of the mixed refrigerant, and at least one of the physical property value of the mixed refrigerant and Reynolds.
  • the physical property value of the natural gas and the physical property value of the mixed refrigerant include at least one of the Prandtl number and the thermal conductivity.
  • the function f3 may be an empirical formula obtained by measuring a change in the UA value when changing the supply condition of the natural gas and the supply condition of the mixed refrigerant.
  • the functions f1, f2, and f3 may be empirical formulas obtained by measuring changes in UA values when various supply conditions are changed. Even a correlation expression obtained based on a relationship between a plurality of UA values obtained by executing a simulation model from one plurality of operation data and supply conditions such as a mass flow rate of natural gas or a mixed refrigerant in each operation data. Good.
  • the configuration of the natural gas liquefaction apparatus 1 is not limited to the configuration shown in FIG. 1, and various known configurations can be applied.
  • Natural gas liquefaction apparatus 3 Pre-cooling heat exchanger 4: Cryogenic heat exchanger 6: First compressor 7: Second compressor 8: Third compressor 11A to 11F, 26, 29, 31: Expansion valve 14 , 15, 35, 36: coolers 41 to 44: replenishment amount control valves 46, 47: extraction amount control valve 50: control device

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Abstract

Le problème décrit par la présente invention est d'augmenter le rendement énergétique d'un dispositif de liquéfaction de gaz naturel. La solution selon l'invention porte sur un procédé de détermination d'une composition de fluide frigorigène mixte pour un dispositif de liquéfaction de gaz naturel, comprenant : une étape de génération de modèle pour générer un modèle de simulation du dispositif de liquéfaction de gaz naturel sur la base d'une première condition, qui est une condition de fonctionnement dudit dispositif; une étape de calcul de UA0 pour calculer UA0 sur la base du modèle de simulation et de la première condition; un dispositif de calcul de UA1 pour calculer UA1 sur la base d'une nouvelle condition d'alimentation NG et de UA0; une étape de génération de composition candidate pour générer une pluralité de compositions candidates pour la composition de fluide frigorigène mixte; une étape d'estimation de puissance pour calculer UA2 et calculer la consommation d'énergie totale d'un compresseur pour chacune des compositions candidates au moyen de l'utilisation du modèle de simulation pour effectuer une simulation sur la base de la nouvelle condition d'alimentation NG, des compositions candidates et de UA1; et une étape de détermination de composition pour déterminer une composition candidate ayant la plus petite quantité de consommation d'énergie totale, parmi la pluralité de compositions candidates, comme nouvelle composition pour le fluide frigorigène mixte.
PCT/JP2018/026481 2018-07-13 2018-07-13 Procédé de détermination de composition de fluide frigorigène mixte pour dispositif de liquéfaction de gaz naturel Ceased WO2020012637A1 (fr)

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JP2018559403A JP6470482B1 (ja) 2018-07-13 2018-07-13 天然ガス液化装置の混合冷媒組成の決定方法

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05196349A (ja) * 1991-07-31 1993-08-06 Air Prod And Chem Inc ガス液化プロセスのコントロールシステム
JP2008503605A (ja) * 2004-06-18 2008-02-07 エクソンモービル アップストリーム リサーチ カンパニー 炭化水素流体処理プラントの設計
JP2013540973A (ja) * 2010-03-25 2013-11-07 ザ・ユニバーシティ・オブ・マンチェスター 冷却プロセス
JP6286812B2 (ja) * 2016-03-10 2018-03-07 日揮株式会社 天然ガス液化装置の混合冷媒組成の決定方法

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Publication number Priority date Publication date Assignee Title
JPH05196349A (ja) * 1991-07-31 1993-08-06 Air Prod And Chem Inc ガス液化プロセスのコントロールシステム
JP2008503605A (ja) * 2004-06-18 2008-02-07 エクソンモービル アップストリーム リサーチ カンパニー 炭化水素流体処理プラントの設計
JP2013540973A (ja) * 2010-03-25 2013-11-07 ザ・ユニバーシティ・オブ・マンチェスター 冷却プロセス
JP6286812B2 (ja) * 2016-03-10 2018-03-07 日揮株式会社 天然ガス液化装置の混合冷媒組成の決定方法

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QIU GUODONG ET AL.: "Numerical study on the condensation flow and heat transfer characteristics of hydrocarbon mixtures inside the tubes of liquefied natural gas coil-wound heat exchangers", A PPLIED THERMAL ENGINEERING, vol. 140, 25 May 2018 (2018-05-25), pages 775 - 786, XP085409942, DOI: 10.1016/j.applthermaleng.2018.05.090 *

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