Classifications

• • 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
  • F17C3/00—Vessels not under pressure
  • F17C3/02—Vessels not under pressure with provision for thermal insulation
  • F17C3/025—Bulk storage in barges or on ships
  • F17C3/027—Wallpanels for so-called membrane tanks
• • 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
  • F17C3/00—Vessels not under pressure
  • F17C3/02—Vessels not under pressure with provision for thermal insulation
  • F17C3/08—Vessels not under pressure with provision for thermal insulation by vacuum spaces, e.g. Dewar flask
• • 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
  • F17C2201/00—Vessel construction, in particular geometry, arrangement or size
  • F17C2201/01—Shape
  • F17C2201/0147—Shape complex
  • F17C2201/0157—Polygonal
• • 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
  • F17C2201/00—Vessel construction, in particular geometry, arrangement or size
  • F17C2201/05—Size
  • F17C2201/052—Size large (>1000 m3)
• • 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
  • F17C2203/00—Vessel construction, in particular walls or details thereof
  • F17C2203/03—Thermal insulations
  • F17C2203/0304—Thermal insulations by solid means
• • 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
  • F17C2203/00—Vessel construction, in particular walls or details thereof
  • F17C2203/03—Thermal insulations
  • F17C2203/0391—Thermal insulations by vacuum
• • 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
  • F17C2203/00—Vessel construction, in particular walls or details thereof
  • F17C2203/06—Materials for walls or layers thereof; Properties or structures of walls or their materials
  • F17C2203/0602—Wall structures; Special features thereof
  • F17C2203/0612—Wall structures
  • F17C2203/0626—Multiple walls
  • F17C2203/0631—Three or more walls
• • 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
  • F17C2221/00—Handled fluid, in particular type of fluid
  • F17C2221/03—Mixtures
  • F17C2221/032—Hydrocarbons
  • F17C2221/033—Methane, e.g. natural gas, CNG, LNG, GNL, GNC, PLNG
• • 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
  • F17C2221/00—Handled fluid, in particular type of fluid
  • F17C2221/03—Mixtures
  • F17C2221/032—Hydrocarbons
  • F17C2221/035—Propane butane, e.g. LPG, GPL
• • 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
  • F17C2223/00—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel
  • F17C2223/01—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel characterised by the phase
  • F17C2223/0146—Two-phase
  • F17C2223/0153—Liquefied gas, e.g. LPG, GPL
• • 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
  • F17C2223/00—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel
  • F17C2223/01—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel characterised by the phase
  • 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
• • 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
  • F17C2223/00—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel
  • F17C2223/01—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel characterised by the phase
  • F17C2223/0146—Two-phase
  • F17C2223/0153—Liquefied gas, e.g. LPG, GPL
  • F17C2223/0169—Liquefied gas, e.g. LPG, GPL subcooled
• • 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
  • F17C2223/00—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel
  • F17C2223/03—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel characterised by the pressure level
  • F17C2223/033—Small pressure, e.g. for liquefied gas
• • 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
  • F17C2223/00—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel
  • F17C2223/04—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel characterised by other properties of handled fluid before transfer
  • F17C2223/042—Localisation of the removal point
  • F17C2223/043—Localisation of the removal point in the gas
• • 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
  • F17C2223/00—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel
  • F17C2223/04—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel characterised by other properties of handled fluid before transfer
  • F17C2223/042—Localisation of the removal point
  • F17C2223/046—Localisation of the removal point in the liquid
  • F17C2223/047—Localisation of the removal point in the liquid with a dip tube
• • 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
  • F17C2227/00—Transfer of fluids, i.e. method or means for transferring the fluid; Heat exchange with the fluid
  • F17C2227/03—Heat exchange with the fluid
  • F17C2227/0337—Heat exchange with the fluid by cooling
  • F17C2227/0339—Heat exchange with the fluid by cooling using the same fluid
• • 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
  • F17C2227/00—Transfer of fluids, i.e. method or means for transferring the fluid; Heat exchange with the fluid
  • F17C2227/03—Heat exchange with the fluid
  • F17C2227/0337—Heat exchange with the fluid by cooling
  • F17C2227/0341—Heat exchange with the fluid by cooling using another fluid
  • F17C2227/0355—Heat exchange with the fluid by cooling using another fluid in a closed loop
• • 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
  • F17C2227/00—Transfer of fluids, i.e. method or means for transferring the fluid; Heat exchange with the fluid
  • F17C2227/03—Heat exchange with the fluid
  • F17C2227/0367—Localisation of heat exchange
  • F17C2227/0369—Localisation of heat exchange in or on a vessel
  • F17C2227/0374—Localisation of heat exchange in or on a vessel in the liquid
• • 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
  • F17C2227/00—Transfer of fluids, i.e. method or means for transferring the fluid; Heat exchange with the fluid
  • F17C2227/03—Heat exchange with the fluid
  • F17C2227/0367—Localisation of heat exchange
  • F17C2227/0388—Localisation of heat exchange separate
• • 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
  • F17C2227/00—Transfer of fluids, i.e. method or means for transferring the fluid; Heat exchange with the fluid
  • F17C2227/03—Heat exchange with the fluid
  • F17C2227/0367—Localisation of heat exchange
  • F17C2227/0388—Localisation of heat exchange separate
  • F17C2227/0393—Localisation of heat exchange separate using a vaporiser
• • 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
  • F17C2250/00—Accessories; Control means; Indicating, measuring or monitoring of parameters
  • F17C2250/03—Control means
  • F17C2250/032—Control means using computers
• • 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
  • F17C2250/00—Accessories; Control means; Indicating, measuring or monitoring of parameters
  • F17C2250/04—Indicating or measuring of parameters as input values
  • F17C2250/0404—Parameters indicated or measured
  • F17C2250/043—Pressure
• • 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
  • F17C2250/00—Accessories; Control means; Indicating, measuring or monitoring of parameters
  • F17C2250/04—Indicating or measuring of parameters as input values
  • F17C2250/0404—Parameters indicated or measured
  • F17C2250/0439—Temperature
• • 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
  • F17C2250/00—Accessories; Control means; Indicating, measuring or monitoring of parameters
  • F17C2250/04—Indicating or measuring of parameters as input values
  • F17C2250/0486—Indicating or measuring characterised by the location
  • F17C2250/0491—Parameters measured at or inside the vessel
• • 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
  • F17C2250/00—Accessories; Control means; Indicating, measuring or monitoring of parameters
  • F17C2250/06—Controlling or regulating of parameters as output values
  • F17C2250/0605—Parameters
  • F17C2250/0626—Pressure
• • 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
  • F17C2250/00—Accessories; Control means; Indicating, measuring or monitoring of parameters
  • F17C2250/06—Controlling or regulating of parameters as output values
  • F17C2250/0689—Methods for controlling or regulating
  • F17C2250/0694—Methods for controlling or regulating with calculations
• • 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
  • F17C2260/00—Purposes of gas storage and gas handling
  • F17C2260/01—Improving mechanical properties or manufacturing
  • F17C2260/011—Improving strength
• • 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
  • F17C2270/0102—Applications for fluid transport or storage on or in the water
  • F17C2270/0105—Ships
  • F17C2270/0107—Wall panels

Definitions

• the invention relates to the field of tanks, waterproof and thermally insulating membranes, for the storage of a liquefied gas.
• Watertight and thermally insulating membrane tanks are used in particular for the storage of liquefied natural gas (LNG).
• LNG liquefied natural gas
• the multilayer structure comprises, from the outside towards the inside of the tank, a secondary thermal insulating barrier comprising insulating elements resting against a bearing structure, a secondary sealing membrane resting against the secondary thermally insulating barrier, a thermally insulating barrier primary element comprising insulating elements resting against the secondary sealing membrane and a primary sealing membrane intended to be in contact with the liquefied gas contained in the tank and resting against the primary thermally insulating barrier.
• Such membrane vessels are sensitive to the pressure differences on either side of each of the membranes, and in particular to the pressure difference on either side of the primary waterproofing membrane. Indeed, an overpressure of the primary thermally insulating barrier relative to the interior of the tank is likely to cause tearing of the primary waterproofing membrane. Therefore, to guarantee the integrity of the primary sealing barrier, it is preferable to maintain a pressure inside the primary thermally insulating barrier which is lower than that inside the vessel so that the The pressure difference across the primary waterproofing membrane tends to press the latter against the secondary thermally insulating barrier and not to tear it away from the secondary insulating barrier.
• An idea underlying the invention is to propose a method for controlling a pumping device connected to a thermally insulating barrier of a sealed and thermally insulating tank which makes it possible to effectively protect at least one waterproofing membrane from the tank.
• the invention provides a method for controlling a pumping device associated with a sealed and thermally insulating tank; said vessel containing a liquefied gas having a liquid phase and a vapor phase and having walls having a multilayer structure comprising a sealing membrane in contact with the liquefied gas and a thermally insulating barrier disposed between the sealing membrane and a carrier structure said thermally insulating barrier comprising solids and a gaseous phase; said pump device including a vacuum pump connected to the thermally insulating barrier for placing the gas phase under a negative relative pressure; said method comprising the steps of: -measuring a pressure P1 of the gaseous phase of the thermally insulating barrier;
• determining a set pressure P c by means of a relation P c1 f
• Such a method is particularly effective for protecting the waterproofing membrane when the tank is placed under a pressure below atmospheric pressure (which was not previously provided in the state of the art). This is particularly likely to occur when the liquefied gas is mainly stored in the tank in a thermodynamic sub-cooled state, that is to say at a temperature that is below the liquid-vapor equilibrium temperature of the gas considered at the gas storage pressure in the tank.
• the Applicant has recently developed cooling devices for reducing the temperature of a portion of the liquefied gas stored in the tank below its liquid-vapor equilibrium temperature so as to limit the natural evaporation of the liquefied gas and allow its durable storage. Such a process is therefore particularly adapted to meet the specific needs of vessels equipped with such cooling devices.
• the vapor phase in the gaseous atmosphere of the tank and the liquid phase of the liquefied gas are not, in any point of the tank, in equilibrium.
• the vapor phase is likely to heat up and tends to stratify inside the tank. It can thus be seen temperature gradients of the order of 100 ° C in the vapor phase when the tank is low and no stirring is implemented in the tank to homogenize the temperature of the vapor phase.
• the interface between the vapor phase and the liquid phase is in the stationary state, in equilibrium. It is at this interface that the vapor phase condenses or the liquid phase evaporates as a function of local temperature and pressure conditions.
• the interface between the vapor phase and the liquid phase is likely to change abrupt geometry, position and constitution.
• a sudden movement of the cargo in the tank is likely to cause instantaneous condensation of a large amount of gaseous phase and, consequently, to cause a sudden depression of the internal space of the tank.
• such a method may have one or more of the following characteristics:
• the variable T is obtained by measuring the temperature of the liquid phase of the liquefied gas or by measuring an operating parameter of the liquefied gas cooling device representative of the minimum temperature threshold likely to be reached by the phase; liquid liquefied gas.
• variable T is obtained by receiving an operating parameter of the liquefied gas cooling device representative of the minimum temperature threshold likely to be reached by the liquid phase of the liquefied gas.
• the function f 1 is an affine transformation of a function representative of a liquid-vapor equilibrium curve in a pressure-temperature diagram of the liquefied gas or of a component of the liquefied gas which, among the components constituting the liquefied gas which are present in a molar proportion greater than 5%, has the lowest vaporization temperature.
• the constant ⁇ is, for example, between 10 and 30 mbar.
• the waterproofing membrane is a primary waterproofing membrane and the thermally insulating barrier is a primary thermal-insulating barrier, the multilayer structure further comprising a secondary thermal-insulating barrier which rests against the supporting structure and comprises solids and a phase gas and a membrane secondary sealing arrangement disposed between the secondary heat-insulating barrier and the primary heat-insulating barrier.
• the pumping device comprises a second vacuum pump connected to the secondary thermally insulating barrier in order to place the gaseous phase of the secondary thermally insulating barrier under a negative relative pressure; the process comprising the steps of:
• the function f 2 is an affine transformation of a function representative of a liquid-vapor equilibrium curve in a pressure-temperature diagram of the liquefied gas or of a component of the liquefied gas which, among the components constituting the liquefied gas that are present in a molar proportion greater than 5%, has the lowest vaporization temperature of a liquid-vapor equilibrium curve of the liquefied gas or a major component of the liquefied gas in a pressure-temperature diagram.
• ⁇ 2 is for example between 10 and 30 mbar.
• h P1 - ⁇ ' 2 ; ⁇ ' 2 being a constant.
• the constant ⁇ ' 2 is for example between 10 and 30 mbar.
• the invention relates to a control method comprising:
• Another idea underlying the invention is to provide a method for controlling a device for cooling a liquefied gas that effectively protects at least one sealing membrane of the tank.
• the invention relates to a method for controlling a device for cooling a liquefied gas associated with a liquefied gas storage facility; said installation comprising:
• a sealed and thermally insulating tank for containing a liquefied gas in a two-phase form with a liquid phase and a vapor phase;
• the vessel having walls having a multilayer structure comprising a sealing membrane in contact with the liquefied gas and a thermally insulating barrier disposed between the sealing membrane and a supporting structure, said thermally insulating barrier comprising solids and a gaseous phase ;
• a pressure sensor capable of measuring a pressure P of the gas phase in the thermally insulating barrier
• a pumping device comprising a vacuum pump connected to the thermally insulating barrier and arranged to place the gaseous phase of the thermally insulating barrier under a negative relative pressure and a control module which is arranged to control the vacuum pump so as to enslave the pressure P1 of the gaseous phase of the thermally insulating barrier to a set pressure P c ;
• the cooling device being arranged to lower the temperature of a portion of the liquefied gas below the liquid-vapor equilibrium temperature of the liquefied gas to the storage pressure of the liquefied gas in the tank; said method of control of the liquefied gas cooling device comprising:
• such a method may have one or more of the following characteristics:
• Function f 3 is a function representative of a liquid-vapor equilibrium curve in a pressure-temperature diagram of the liquefied gas or of a component of the liquefied gas which, among the components constituting the liquefied gas, which are present in a proportion in mole greater than 5%, has the lowest vaporization temperature.
• a minimum temperature threshold T min is determined which corresponds to the liquid-vapor equilibrium temperature of the liquefied gas or of a major component of the liquefied gas at the set pressure P c1 of such so that the liquid phase of the liquefied gas contained in the tank can not reach a sufficiently low temperature so that a sudden movement of the cargo causes a depression in the interior space of the tank which is greater than the depression prevailing in the heat barrier insulating.
• the invention also provides a liquefied gas storage facility comprising:
• a sealed and thermally insulating tank for containing a liquefied gas in a two-phase form with a liquid phase and a vapor phase;
• the vessel having walls having a multilayer structure comprising a sealing membrane in contact with the liquefied gas and a thermally insulating barrier disposed between the sealing membrane and a supporting structure, said thermally insulating barrier comprising solids and a gaseous phase ;
• a pressure sensor capable of measuring the pressure of the gas phase in the thermally insulating barrier
• a pumping device comprising a vacuum pump connected to the thermally insulating barrier and arranged to place the gaseous phase of the barrier thermally insulating under a negative relative pressure and a control module which is arranged to:
• such an installation may have one or more of the following characteristics:
• the installation further comprises a temperature sensor adapted to measure the temperature T of the liquid phase of the liquefied gas and deliver it to the control module.
• the installation further comprises a liquefied gas cooling device arranged to lower the temperature of a portion of the liquefied gas below the liquid-vapor equilibrium temperature of the liquefied gas to the liquefied gas storage pressure in the tank.
• the cooling device is arranged to meet a minimum temperature threshold for the liquid phase of the liquefied gas and wherein the control module is connected to the cooling device and is arranged to determine the set pressure P c1 by taking as variable T the minimum temperature threshold.
• the installation comprises a sensor capable of measuring an operating parameter of the liquefied gas cooling device representative of the minimum threshold likely to be reached by the liquid phase of the liquefied gas.
• the waterproofing membrane is a primary waterproofing membrane and the thermally insulating barrier is a primary thermally insulating barrier, the multilayer structure further comprising a secondary thermally insulating barrier which rests against the supporting structure and g comprises solids and a gaseous phase and a secondary sealing membrane disposed between the secondary thermally insulating barrier and the primary thermally insulating barrier.
• the installation further comprises a second pressure sensor capable of measuring the pressure P 2 in the secondary thermally insulating barrier.
• the pumping device further comprises a second vacuum pump connected to the secondary thermally insulating barrier to place the gas phase of the secondary thermally insulating barrier under a negative relative pressure.
• the control module is arranged to control the second vacuum pump so as to slave the pressure P2 of the gas phase of the secondary thermally insulating barrier to a set pressure P c2 .
• the device for cooling the liquefied gas is a vaporization device for cooling the liquefied gas; said vaporization device comprising:
• a vaporization chamber arranged in the interior space of the tank, the vaporization chamber comprising heat exchange walls allowing a heat exchange between an interior space of the vaporization chamber and the liquefied gas present in the chamber; interior space of the tank;
• an inlet circuit comprising an inlet opening into the interior of the vessel for withdrawing a liquid-phase flow of liquefied gas into the vessel and a pressure-loss element opening into the interior space of the vaporization enclosure to relax the flow of gas withdrawn;
• an output circuit arranged to evacuate the stream of gas taken off, in the gas phase from the vaporization chamber to a gas-phase gas utilization circuit; said output circuit comprising a vacuum pump able to suck up the flow of gas into the vaporization chamber, to discharge it to the vapor phase gas utilization circuit and to maintain in the vaporization chamber a lower absolute pressure. at atmospheric pressure.
• the device for cooling the liquefied gas comprises a vapor phase gas sampling circuit comprising: an inlet opening into the interior space of the tank above a maximum filling height of the tank so as to open, when the tank is filled, in a zone of the vapor phase in contact with a zone of the tank; interface separating the lower liquid phase and the higher vapor phase; and
• a vacuum pump capable of drawing through the inlet a vapor phase gas stream present in the zone of the vapor phase, to discharge it to a vapor phase gas utilization circuit and to maintain in the zone of the vapor phase a pressure lower than the atmospheric pressure so that a vaporization of the liquid phase is favored at the interface zone and that liquefied gas in contact with the interface zone is placed in a state liquid-vapor two-phase equilibrium system in which the liquefied gas has a temperature below the liquid-vapor equilibrium temperature of said liquefied gas at atmospheric pressure.
• Such an installation may be part of an onshore storage facility, for example to store LNG or be installed in a floating structure, coastal or deep-water, including a LNG tank, a floating storage and regasification unit (FSRU) , a floating production and remote storage unit (FPSO) and others.
• FSRU floating storage and regasification unit
• FPSO floating production and remote storage unit
• a vessel comprises a double hull and a plant mentioned above, the tank of the liquefied gas storage installation being disposed in the double hull.
• the invention also provides a method for loading or unloading such a vessel, in which a fluid is conveyed through isolated pipes from or to a floating or land storage facility to or from the tank of the vessel. ship.
• the invention also provides a transfer system for a fluid, the system comprising the abovementioned vessel, insulated pipes arranged to connect the vessel installed in the hull of the vessel to a floating or ground storage facility. and a pump for driving fluid through the insulated pipelines from or to the floating or land storage facility to or from the vessel vessel.
• FIG. 1 schematically illustrates a storage installation and cooling of a liquefied gas according to a first embodiment.
• FIG. 2 schematically illustrates a facility for storing and cooling a liquefied gas according to a second embodiment.
• FIG. 3 schematically illustrates a facility for storing and cooling a liquefied gas according to a third embodiment.
• FIG. 4 schematically illustrates a facility for storing and cooling a liquefied gas according to a fourth embodiment.
• FIG. 5 is a liquid-vapor equilibrium diagram of methane.
• FIG. 6 is a schematic cutaway representation of a methane tanker equipped with a tank and a loading / unloading terminal of the tank.
• gas has a generic character and refers indifferently to a gas consisting of a single pure body or a gaseous mixture consisting of a plurality of components.
• a liquefied gas thus refers to a chemical body or a mixture of chemical bodies which has been placed in a liquid phase at low temperature and which would occur in a vapor phase under normal conditions of temperature and pressure.
• FIG. 1 a facility 1 for storing and cooling a liquefied gas according to a first embodiment is shown.
• Such an installation 1 can be installed on a floating structure such as a tanker, a liquefaction barge or regasification.
• the installation 1 comprises a sealed and thermally insulating tank 2 membranes.
• the vessel 2 comprises walls having a multilayer structure comprising, from the outside to the inside of the vessel 2, a secondary thermally insulating barrier 3 comprising a gaseous phase and insulating elements resting against a carrier structure 4, a secondary sealing membrane 5 resting against the secondary thermally insulating barrier 3, a primary thermally insulating barrier 6 having insulating elements resting against the secondary sealing membrane 5 and a gas phase and a primary sealing membrane 7 intended to be in contact with the liquefied gas 8 contained in the tank.
• such tanks 2 membrane are described in patent applications W014057221, FR2691520 and FR2877638.
• the tank is equipped with a vapor collection device, not shown, passing through a ceiling wall of the tank and opening into the upper part of the internal space of the tank.
• a vapor collection device not shown, passing through a ceiling wall of the tank and opening into the upper part of the internal space of the tank.
• a device is equipped with a valve arranged to allow evacuation of the steam from the inside to the outside of the tank when the pressure inside the internal space of the tank 2 is greater than a threshold.
• the valve is furthermore configured so as to prevent a flow of gas from flowing in the collecting device. of steam, from the outside to the inside of the tank 2 and thus allows the internal space of the vessel 2 to be depressurized.
• a device for collecting vapor is described in the document WO2013093261.
• Liquefied gas 8 is a combustible gas.
• the liquefied gas 8 may in particular be a liquefied natural gas (LNG), that is to say a gaseous mixture comprising mainly methane and one or more other hydrocarbons, such as ethane, propane, n- butane, i-butane, n-pentane, i-pentane, neopentane, and nitrogen in a small proportion.
• the fuel gas may also be ethane or a liquefied petroleum gas (LPG), that is to say a mixture of hydrocarbons from petroleum refining comprising mainly propane and butane.
• LPG liquefied petroleum gas
• the liquefied gas 8 is stored in the interior space of the vessel 2 in a two-phase liquid-vapor state.
• the liquefied gas 8 is therefore present in the vapor phase in the upper part of the tank 2 and in the liquid phase in the lower part of the tank 2.
• the installation 1 further comprises a device for cooling the liquefied gas stored in the tank 2 arranged to lower the temperature of a portion of the liquid phase of the liquefied gas 8 below the liquid-vapor equilibrium temperature of said gas liquefied 7, the storage pressure of the liquefied gas 8 in the tank 2.
• a portion of the liquefied gas is placed in a thermodynamic state undercooled.
• the installation comprises a vaporization device 20 intended to take a flow of gas in the liquid phase from the tank 2 and to relax it in order to vaporize it using heat. latent vaporization of the gas to cool the liquefied gas 8 remained in the tank 2.
• FIG. 5 represents a liquid-vapor equilibrium diagram of the methane.
• This diagram represents the domain, denoted L, in which the methane is in the liquid phase and the domain, denoted V, in which the methane is in the vapor phase, as a function of the pressure represented on the abscissa and the temperature represented on the ordinate .
• the point P1 represents a state of two-phase equilibrium corresponding to the state of the methane stored in the tank 2 at atmospheric pressure and at a temperature of about -162 ° C.
• methane in such a state of equilibrium is taken from the tank 2 and then expanded in the vaporization device 20, for example at an absolute pressure of about 500 mbar, the equilibrium of the expanded methane moves to the left until at point P2.
• the methane thus relaxed undergoes a decrease in temperature of about 7 ° C.
• the methane removed being brought into thermal contact via the vaporization device 20 with the methane remaining in the tank 2, it vaporizes at least partially and, by vaporizing, subtracted from the liquid methane stored in the tank 2 the necessary calories to its vaporization which allows to cool the liquid methane remaining in the tank 2.
• the methane remaining in the tank 2 is therefore placed at a temperature below its equilibrium temperature at the storage pressure of the methane in the tank 2.
• the vaporization device 20 comprises: an inlet circuit comprising an intake 21 immersed in the liquid phase of the liquefied gas 8 stored in the tank 2;
• one or more evaporation chambers 22 immersed in the liquid phase and / or the vapor phase of the liquefied gas 8 and comprising heat exchange walls, immersed in the liquefied gas stored in the tank 2, so as to put in contact with each other; thermal the flow of gas taken with the liquefied gas remaining in the tank 2; and
• the input circuit is equipped with one or more pressure drop members, not shown, for creating a pressure drop and opening inside the vaporization chamber 22 so as to relax the flow of liquefied gas collected.
• the vaporization device is also equipped with a vacuum pump 24, arranged outside the tank and associated with the output circuit 23.
• the vacuum pump 24 makes it possible to suck a stream of liquefied gas stored in the tank 2 towards the tank.
• vaporization chamber 22 and vapor phase to a vapor phase gas utilization circuit 25.
• the absolute working pressure prevailing inside the vaporization chamber 22 is between 120 and 950 mbar, advantageously between 650 and 850 mbar, and for example of the order of 750 mbar.
• the vapor phase gas utilization circuit 25 may in particular be connected to power generation equipment of the powertrain, not shown, for propelling the ship.
• power generation equipment is chosen in particular from heat engines, fuel cells and gas turbines.
• the installation 1 is equipped with another device for cooling the liquefied gas making it possible to place the liquefied gas 8 in a subcooled thermodynamic state.
• the installation 1 here comprises a gas sampling circuit in the vapor phase 9.
• the vapor phase gas sampling circuit 9 comprises a duct 10 passing through a wall of the tank 2 in order to define a passage of evacuation of the vapor phase, from the inside to the outside of the tank 2.
• the duct 10 has an intake 1 1 opening into the interior of the interior space of the tank 2 in a vacuum bell 31.
• the vacuum bell 31 is a hollow body disposed in the upper part of the internal space of the tank 2 so that its upper portion is in contact and filled with the vapor phase liquefied gas 8 stored in the tank 2 and that its lower portion is immersed in the liquid phase of the liquefied gas 8 stored in the tank 2.
• the inlet 11 of the vapor phase gas sampling circuit 9 opens into the upper portion of the depression bell 20.
• the sampling circuit 9 also comprises a vacuum pump 12 which is connected, upstream, to the pipe and, downstream, to a vapor phase gas utilization circuit 13.
• the vacuum pump 12 is thus able to suck through the pipe 10, a vapor phase gas stream present in the vacuum chamber 31 and to discharge it to the vapor phase gas utilization circuit 13.
• the sampling circuit 9 here comprises a valve 19 or a non-return valve, arranged upstream or downstream of the vacuum pump 12 and thus avoiding a return of the vapor phase gas flow towards the interior space of the tank 2.
• the vacuum pump 12 is able to generate in the upper portion of the vacuum bell 31 a pressure less than atmospheric pressure, which makes it possible to promote a vaporization of the liquefied gas inside the vacuum bell 20. Therefore, the vapor phase inside the vacuum bell 31 being placed at a pressure lower than the atmospheric pressure, the vaporization of the liquefied gas 8 is favored at the liquid / vapor interface inside the vacuum bell 31 while the liquefied gas 8 stored in the tank 2 is placed in a state of two-phase liquid-vapor equilibrium in which the liquefied gas 8 has a temperature lower than the liquid-vapor equilibrium temperature of said liquefied gas at atmospheric pressure.
• the cooling device comprises a liquefaction device comprising a first circuit 34 comprising an inlet 32 able to collect liquefied gas in the vapor phase in the interior space of the tank 2 and a outlet 33 adapted to return liquefied gas in the liquid phase in the interior space of the tank 2.
• the liquefaction device further comprises a refrigerant circuit 35 in which a refrigerant circulates.
• the refrigerating circuit 35 comprises a compressor 36, a condenser 37, a pressure reducer 38 and an evaporator 39 in which the refrigerant evaporates by taking calories from the liquefied gas circulating in the reactor.
• first circuit 34 Such a cooling device is in particular disclosed in the document EP2853479.
• the cooling device comprises a refrigerating unit 40 which circulates liquid nitrogen at about -196 ° C in a pin tube 41, which has the effect of cooling the liquefied gas around the tube 41. Since the refrigerated liquefied gas becomes denser, it undergoes a downward movement in the tank 2 and the liquefied gas not yet refrigerated conversely undergoes an upward movement. This convection movement is channeled by the convection well 42 in order to create this convection movement throughout the tank 2. During its circulation, the liquid nitrogen undergoes evaporation, which makes it possible to benefit from the latent heat of evaporation. nitrogen to cool the liquefied gas. At the outlet of the tube 23, the nitrogen is re-liquefied in the refrigerating unit 41.
• a cooling device is described in particular in the application FR2785034.
• the installation 1 comprises, in the embodiment shown, a pumping device which comprises a vacuum pump 16 which is connected to a pipe 17 opening into the internal space of the barrier thermally insulating primary 6 and a vacuum pump 14 which is connected to a pipe 15 opening into the internal space of the secondary thermally insulating barrier 3.
• a pumping device aims to maintain the gaseous phases inside the thermally barrier primary and secondary insulators 6 at pressures lower than the pressure prevailing in the interior space of the tank 2.
• the pressure differences between the membranes tend to press them outwards and not to tear them towards the outside. inside the tank 2.
• the vacuum pumps 14, 16 are cryogenic pumps, that is to say able to withstand cryogenic temperatures below -150 ° C. They are also compliant with the ATEX regulations, that is to say designed to avoid any risk of explosion.
• the vacuum pumps 14, 16 can be made of various ways, for example Roots (ie rotating lobes), vane, liquid ring, screw, with a venturi type effector.
• the installation 1 further comprises a control module 26 for controlling the vacuum pump 14 and the vacuum pump 16 so as to regulate the pressures prevailing in the primary heat-insulating barrier 6 and in the secondary heat-insulating barrier 3.
• the control module 26 may comprise a single element, as in the embodiment shown, or two elements; these being respectively associated with the control of one and the other of the two vacuum pumps 14, 16.
• the control module 26 is connected to at least one temperature sensor 27 which is immersed in the liquid phase of the liquefied gas 8 stored in the tank 2 and thus makes it possible to deliver a measurement of the temperature of the liquid phase of the liquefied gas 8 stored in the tank 2.
• the temperature sensor 27 is placed close to the bottom of the tank 2.
• the The temperature 27 is further positioned near the heat exchange walls of the vaporization chamber 22.
• the temperature sensor 27 may be made by any means such as a thermocouple or platinum resistance probe, for example.
• the installation 1 further comprises at least one pressure sensor 28 for delivering a measurement of the pressure P1 of the gas phase inside the primary thermally insulating barrier 6 and a pressure sensor 29 for delivering a measuring the pressure P2 of the gas phase inside the secondary thermally insulating barrier 3.
• the control module 26 is arranged to generate a control value of the vacuum pump 16 as a function of a set pressure P c1 and of the measurement of the pressure P1 of the gas phase inside the thermally insulating barrier. primary 6 so as to slave the pressure P1 to the set pressure P c1 .
• the control module 26 is arranged to generate a control value of the vacuum pump 14 as a function of a set pressure P c 2 and the measurement of the pressure P2 of the gas phase inside. of the primary thermally insulating barrier 6 so as to slave the pressure P2 to the set pressure P c 2.
• control module 26 is also designed to determine, at any time, the set pressure P c for the primary thermally insulating barrier 6, as a function of the temperature measured by the temperature sensor 27.
• set pressure P c is determined by means of the following relation:
• the function f 1 is an affine transformation of a function g representative of the liquid-vapor equilibrium curve in a pressure-temperature diagram of the liquefied gas or the component of the liquefied gas which, among the other components of the liquefied gas which are present in a significant amount (i.e. in a molar proportion greater than 5%) has the lowest vaporization temperature at atmospheric pressure.
• the function f is, for example, of the following form:
• - ⁇ a constant, for example of the order of 10 to 30 mbar.
• the function g makes it possible to determine the saturation vapor pressure associated with the temperature of the liquid phase measured in the tank 2 and thus makes it possible to determine a pressure value lowering the absolute pressure likely to be reached in the event of condensation of the vapor phase. liquefied gas stored in the tank.
• the function g is representative of the liquid vapor equilibrium curve of the component which among the components present in significant amounts is the most volatile.
• the function g used is representative of the liquid vapor equilibrium curve of pure methane. Therefore, taking as reference the liquid-vapor equilibrium curve of the most volatile component, a pressure is determined saturating vapor which reduces the saturation vapor pressure of the gaseous mixture. This approach is simple and robust and does not require to determine in real time the composition of the liquefied gas, it being likely to vary over time.
• the equilibrium curve of methane in a pressure-temperature diagram can be approximated by the following function:
• the image of such a temperature by the aforementioned g function is 565 millibars.
• the pressure in the tank is theoretically not likely to fall below an absolute pressure of 565 millibars.
• the set pressure P c1 is then 545 millibars.
• control module 26 is also arranged to determine the set pressure P c2 for the secondary thermally insulating barrier 6.
• the set pressure P c2 is determined as a function of the temperature T measured by the temperature sensor 27 in a manner similar to the set pressure P c2.
• the set pressure P c2 is thus determined by means of of the following relation:
• the function f 2 can be written as:
• g a function representative of the liquid-vapor equilibrium curve of the liquefied gas or of the majority component of the liquefied gas in a pressure-temperature diagram
• - ⁇ 2 a constant, for example of the order of 10 to 30 m bars.
• the reference pressure P c2 is not determined as a function of the temperature measured by the temperature sensor 27 but is determined as a function of the pressure P1 of the gas phase in the primary thermally insulating barrier 6 by the following relation:
• P1 the pressure measured in the gaseous phase of the primary thermally insulating barrier 6.
• ⁇ ' 2 is a positive constant, for example between 10 and 30 mbar.
• ⁇ ' 2 is a negative constant, for example between -10 and -30 mbar.
• the set pressure P c1 for the primary thermally insulating barrier 6 and / or the set pressure P c2 is not determined as a function of a measurement of the temperature of the liquefied gas 8 but by taking as variable T in the abovementioned equations, a variable corresponding to a minimum threshold likely to be reached by the liquid phase of the liquefied gas, for a determined operating state of the liquefied gas cooling device.
• the installation comprises a temperature sensor disposed at the outlet of the vaporization enclosure 22 and measuring the temperature of the vapor phase gas flow flowing inside the vaporization chamber 22 or the temperature of a wall of the vaporization chamber 22.
• the temperature thus measured is representative of the minimum temperature likely to be reached by the liquid phase of the liquefied gas 8 stored inside the tank 2.
• the process of controlling the vacuum pump 16 and the vacuum pump 14 also makes it possible to guarantee that the pressures of the gaseous phases inside the primary 6 and secondary 3 thermally insulating barriers are at all times lower than the pressure in the internal space of the vessel 2.
• the installation may comprise a temperature sensor disposed in the refrigerant circuit and measuring the return temperature of the refrigerant at the outlet of the evaporator 39.
• the temperature thus measured is also representative of the minimum temperature likely to be reached by the phase liquid liquefied gas 8 stored inside the tank 2 and can also be used for the determination of the set pressure P c , and optionally for the determination of the set pressure P c2 .
• the device for cooling the liquefied gas is arranged to respect a minimum temperature threshold T min for the liquid phase of the liquefied gas.
• the cooling device of the liquefied gas is controlled so that the temperature of the liquid phase of the liquefied gas does not fall below said temperature threshold T min .
• the operating parameters of the cooling device are thus set so that the temperature of the liquid phase of the liquefied gas does not fall below the aforementioned threshold.
• the minimum temperature threshold can be guaranteed by setting a corresponding threshold pressure, inside the vaporization chamber 22.
• the minimum temperature threshold can be guaranteed by setting a corresponding threshold pressure inside the bell. with vacuum 31.
• the liquefied gas cooling device is a liquefaction device comprising a gas circulation circuit cooperating with a refrigerant circuit
• compliance with the minimum temperature threshold can be ensured by fixing a flow rate or threshold pressure for the refrigerant in the refrigerant circuit.
• the temperature threshold T min is fixed beforehand and then communicated to the control module 26.
• the reference pressure P c which is previously fixed and then communicated to the cooling device.
• f 3 a representative function of the liquid-vapor equilibrium curve of the liquefied gas or of a major component of the liquefied gas in a pressure-temperature diagram
• a cutaway view of a LNG tank 70 shows a sealed and insulated tank 71 of generally prismatic shape mounted in the double hull 72 of the ship.
• the wall of the tank 71 comprises a primary sealed barrier intended to be in contact with the LNG contained in the tank, a secondary sealed barrier arranged between the primary waterproof barrier and the double hull 72 of the ship, and two insulating barriers arranged respectively between the primary watertight barrier and the secondary watertight barrier and between the secondary watertight barrier and the double hull 72.
• loading / unloading lines 73 arranged on the upper deck of the ship can be connected, by means of appropriate connectors, to a marine or port terminal to transfer a cargo of LNG from or to the tank 71.
• FIG. 6 shows an example of a marine terminal comprising a loading and unloading station 75, an underwater pipe 76 and an onshore installation 77.
• the loading and unloading station 75 is a off-shore fixed installation comprising a movable arm 74 and a tower 78 which supports the movable arm 74.
• the movable arm 74 carries a bundle of insulated flexible pipes 79 that can be connected to the loading / unloading pipes 73.
• the movable arm 74 is adjustable. suitable for all models of LNG carriers.
• a connection pipe (not shown) extends inside the tower 78.
• the loading and unloading station 75 enables the loading and unloading of the LNG tank 70 from or to the shore facility 77.
• the underwater line 76 allows the transfer of the liquefied gas between the loading or unloading station 75 and the onshore installation 77 over a large distance, for example 5 km, which makes it possible to keep the tanker vessel 70 at great distance from the coast during the loading and unloading operations.
• pumps on board the ship 70 and / or pumps equipping the shore installation 77 and / or pumps equipping the loading and unloading station 75 are used.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Filling Or Discharging Of Gas Storage Vessels (AREA)
• Control Of Positive-Displacement Pumps (AREA)

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• 2015
  • 2015-07-29 FR FR1557250A patent/FR3039499B1/fr active Active
• 2016
  • 2016-07-22 WO PCT/FR2016/051921 patent/WO2017017364A2/fr active Application Filing
  • 2016-07-22 CN CN201680040600.8A patent/CN107850260B/zh active Active
  • 2016-07-22 KR KR1020187000624A patent/KR102035643B1/ko active IP Right Grant
  • 2016-07-22 JP JP2018500401A patent/JP6605703B2/ja active Active
  • 2016-07-22 EP EP16750984.3A patent/EP3329172B1/fr active Active
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