Abstract: A method for providing cooling to the superconducting coils of a magnet with cryogenic helium gas at a helium production facility is disclosed. The cryogenic helium gas is fed to the magnet where the helium provides cooling. Cryogenic liquid helium provides additional cooling and fills the helium reservoir. Methods are also provided for recovering vaporized helium from the filling of a magnet and when the magnet is undergoing energization at the helium production facility.

Abstract: A cryogenic system for a superconducting magnet comprises a closed-loop cooling path. The closed-loop cooling path comprises a magnet cooling tube thermally coupled to the superconducting magnet. The magnet cooling tube comprises a cryogen flow passage. The closed-loop cooling tube further comprises a re-condenser is fluidly coupled to the magnet cooling tube through tube sections and a liquid cryogen container fluidly coupled between the magnet cooling tube and the re-condenser. At least one gas tank is fluidly coupled to the magnet cooling tube through a connection tube.

Abstract: A design for equipment and process for reliquefaction of LNG boiloff gas, primarily for shipboard installation, has high thermodynamic efficiency and lower capital cost, smaller size (volume, footprint), lower weight, and less need for maintenance than systems utilizing the prior art. The main refrigerant gas compressor is reduced to a single stage turbocompressor. Optional elements include: compression of boiloff gas at ambient temperature; compression of boiloff gas in one or two stages; turboexpansion of refrigerant gas incorporating one or two turboexpanders; turboexpander energy recovery by mechanical loading, compressor drive, or electric generator; refrigerant sidestream for cooling at the lowest temperatures.

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

Abstract: A method and system of storing and transporting gases comprising mixing the gases with liquid natural gas to form a mixture. The mixture is a liquid-liquid mixture or slurry, and is stored in vessel configured for maintaining the mixture at a first location. The mixture is transported to a second location for storage in vessel for maintaining the mixture. The mixture is removed from the second location storage vessel for separation and use in additional processes.

Abstract: A flowline system for transferring cryogenic liquids between a cryogenic liquid storage tank and a cryogenic liquid receiving/loading facility, and a method of maintaining the system at or marginally above cryogenic temperature during periods between transfer of cryogenic liquids between the cryogenic liquid storage tank and the cryogenic liquid receiving/loading facility are provided. The flowline system has a main transfer conduit and a vapour return line in fluid communication with the cryogenic liquid storage tank and the cryogenic liquid receiving/loading facility. A cooling medium line is provided that is in fluid communication with the main transfer conduit, the vapour return line, and a source of cooled boil-off gas, wherein the cooled boil-off gas is at or marginally above cryogenic temperature.

Abstract: Provided are a pileus-gills type helium condenser and an apparatus, including the same, for condensing helium. The pileus-gills type helium condenser includes: a body having a hemispheric shape and formed of a highly thermally conductive metal; a plurality of cooling fins collectively having a pileus gills-like shape and arranged along the circumference of the body to be spaced apart from one another; and a through-hole formed in the center of the body to be adjacent to the cooling fins.

Abstract: Cryogenic cooling apparatus comprises a chamber for containing coolant and a neck which opens into the chamber. A sleeve is provided which is located, when in use, within the neck. The apparatus includes a cooling element which is located exterior to the sleeve when the sleeve is in use. The sleeve comprises a heat transfer member adapted to cause the cooling element to remove heat from the interior of the sleeve through the use of heat transfer member.

Abstract: An operating system of a liquefied natural gas ship for performing sub-cooled liquefaction of boil-off gas includes a boil-off gas compressor, a cryogenic heat exchanger connected to a refrigerator system, and a first check valve and a first pressure control valve, installed in a pipe between a liquefied natural gas phase separator and a gas combustion unit, and a second check valve and a second pressure control valve, installed in a parallel pipe connected to the pipe in parallel. The parallel pipe is connected to a pipe between the boil-off gas compressor and the cryogenic heat exchanger such that boil-off gas is supplied to an upper vapor region of the liquefied natural gas phase separator. Thus, pressure and level of the liquefied natural gas phase separator are stably controlled. Power consumption is effectively reduced, and economical efficiency is achieved by stable operating pressure and level of the liquefied natural gas phase separator.

Abstract: A method and system are provided for extracting propane vapors from a propane storage tank, and condensing the extracted vapors to form a useable liquid propane product.

Abstract: A turret subassembly for use as part of a cryostat, the turret subassembly comprising a vent tube (32) housing an auxiliary vent (40); a refrigerator sock (34) for housing a refrigerator; a termination box (30) linking the vent tube and the refrigerator sock, and having an opening (52) in one wall (54); and means (38) for attachment of the turret subassembly to a cryogen vessel (12).

Abstract: A method and device for filling a container with liquid gas from a storage tank includes removing the liquefied gas from the storage tank and feeding it to a container via a liquid feed line through use of a delivery system. The gas is compressed in the container and is removed from the container in its gaseous state and is at least partially liquefied by cooling in a heat exchanger. The at least partially liquefied gas is fed into the liquid feed line at the suction end of the delivery device.

Abstract: A design for equipment and process for reliquefaction of LNG boiloff gas, primarily for shipboard installation, has high thermodynamic efficiency and lower capital cost, smaller size (volume, footprint), lower weight, and less need for maintenance than systems utilizing the prior art. The main refrigerant gas compressor is reduced to a single stage turbocompressor. Optional elements include: compression of boiloff gas at ambient temperature; compression of boiloff gas in one or two stages; turboexpansion of refrigerant gas incorporating one or two turboexpanders; turboexpander energy recovery by mechanical loading, compressor drive, or electric generator; refrigerant sidestream for cooling at the lowest temperatures.

Abstract: Disclosed is an apparatus for containing LNG. The apparatus includes an LNG tank containing liquid phase LNG and boil-off gas of LNG, and an circulating device. The circulating device includes an intake port and a discharge port. The circulating device further includes an flowing pathway from the intake port to the discharge port that does not include a forced LNG liquefying device. The intake port is located in an upper portion of the LNG tank, and the discharge port is located in a lower portion of the LNG tank substantially lower than the intake port. The circulating device is configured to suction, through the intake port, boil-off gas from the upper portion of the LNG tank and to discharge boil-off gas, through the discharge port, to the lower portion of the LNG tank.

Abstract: A storage vessel comprises a condenser for condensing boil-off vapor by direct heat exchange with cryogenic liquid feed to the vessel. The condenser comprises a packed arrangement of vapor-liquid contact packing that comprises a top end portion and a bottom end portion. At least said top end portion is open to the vapor space to allow entry of boil-off vapor into the arrangement. The bottom end portion is in fluid flow communication with the lower portion of the storage vessel. One advantage of the invention is that the condenser is open to the vapor space of the storage vessel thereby allowing boil-off vapor to be drawn into the condenser by the condensation action of the vapor.

Abstract: A design for equipment and process for reliquefaction of LNG boiloff gas, primarily for shipboard installation, has high thermodynamic efficiency and lower capital cost, smaller size (volume, footprint), lower weight, and less need for maintenance than systems utilizing the prior art. The main refrigerant gas compressor is reduced to a single stage turbocompressor. Optional elements include: compression of boiloff gas at ambient temperature; compression of boiloff gas in one or two stages; turboexpansion of refrigerant gas incorporating one or two turboexpanders; turboexpander energy recovery by mechanical loading, compressor drive, or electric generator; refrigerant sidestream for cooling at the lowest temperatures.

Abstract: Disclosed is a liquefied natural gas storage apparatus. The apparatus includes a heat insulated tank and liquefied natural gas contained in the tank. The tank has heat insulation sufficient to maintain liquefied natural gas therein such that most of the liquefied natural gas stays in liquid. The contained liquefied natural gas has a vapor pressure from about 0.3 bar to about 2 bar. The apparatus further includes a safety valve configured to release a part of liquefied natural gas contained in the tank when a vapor pressure of liquefied natural gas within the tank becomes higher than a cut off pressure. The cut off pressure is from about 0.3 bar to about 2 bar.

Abstract: An MRI apparatus is provided in which a heat quantity penetrating into the helium tank of a superconducting magnet can be grasped to select a cryo-cooler to be incorporated, whereby consumption of liquid helium is suppressed and a static magnetic field is generated stably. The superconducting magnet includes a superconducting coil, containers 209 and 203 for accommodating the superconducting coil and a refrigerant, a cooler 208 for liquefy gas once again, the gas having been obtained by vaporizing the refrigerant in the containers, and a means for measuring the amount of vaporized refrigerant, while keeping the pressure in the containers at a constant level. The heat quantity penetrating into the containers and the coolability of the cooler are measured accurately, thereby enabling a combination in which the coolability of the cooler to be combined has capacity more than the heat penetration amount.

Abstract: This invention relates to a circulation type liquid helium recondensation device with a contaminant-purging function capable of vaporizing and removing contaminants deposited on the refiner in the device. Helium gas vaporizing in the liquid helium storage tank 2 is pumped by the circulating pump 7 and refined in the refiner 6. The refiner is provided with heaters and also a discharge circuit on the inflow side. The vaporized contaminants generated when the refiner 6 is heated by the heaters are pumped by the circulating pump 7 or the dedicated purge pump 8 and vented to the atmosphere via said discharge circuit.

Abstract: Apparatus and methods for improving the safety and efficiency and decreasing the cost of producing liquid gas, such as liquid oxygen, with a small-scale use liquefaction device, according to various embodiments of the present invention. In one embodiment, liquid oxygen barrier may be added to interface between a cryocooler and a dewar to control rate of liquid oxygen escape upon a tipping of the dewar. A boiloff vessel in fluid communication with the dewar allows expanding gas from a tipped dewar to escape while allowing the liquid to safely settle in the boiloff vessel. A temperature sensing circuit, in proximity with a heat dissipator or cold finger of the cryocooler, is operable to break an electrical power circuit of the cryocooler or cooling fan when a sensed temperature exceeds a predetermined temperature. Oxygen purity of a feed stream of gas may be sensed and/or displayed.

Abstract: An apparatus and method for controlling temperature in a boil-off gas in a liquefaction plant prior to compression, wherein boil-off gas originating from an LNG storage tank is compressed and at least partially condensed, and wherein the condensed boil-off gas (LNG) is being returned to the storage tank. A heat exchanger (20) is connected to the boil-off gas feed line upstream of the compressor (10), and a first conduit (22) fluidly connects the line for returning LNG to the storage tank and the heat exchanger (20). A second conduit (26) fluidly connects the heat exchanger (20) to the boil-off gas feed line at a point upstream of the heat exchanger (20). Boil-off gas is heat exchanged against the cooler (24) prior to being fed into the compressor (10). Thus, the boil-off gas temperature is lowered downstream of the heat exchange.

Abstract: A superconducting device has a cryosystem to whose cryogenic medium a superconducting appliance and a superconducting switching path (which is electrically connected to it and can be activated thermally by means of a heater) of a superconducting switch are thermally coupled. A pipeline, to whose end the superconducting switching path is thermally coupled, is connected to a coolant area of at least one superconducting appliance. To ensure reliable heating of the switching path when the heater is activated, the pipeline has a cross-sectional constriction which impedes the heat exchange with the coolant area.

Abstract: The assembly includes a boil-off gas line that carries storage tank boil-off gas to a condenser that uses condensing liquid from the liquid send-out line to condense the gas. A level control valve on the condensing liquid line actively controls the flow of condensing liquid based on the liquid level in the condenser. A check valve prevents liquid from the send-out line from flowing into the condenser through the condensate line that discharges condensate from the condenser to the send-out line.

Abstract: A cryostat assembly comprises a liquid coolant containing vessel; a mechanical cooler having at least one cooling stage located above the vessel; and a channel for conveying gaseous coolant from the vessel to the cooling stage where the coolant is condensed in use and then returns through the channel to the vessel. An acoustic wave attenuator is located in the channel for attenuating the passage of acoustic energy originating from the mechanical cooler and propagating through the gaseous coolant, while permitting flow of gaseous coolant to the cooling stage and flow of condensed coolant to the vessel.

Abstract: A boil off gas (“BOG”) condenser for use in LNG handling facilities which provides compensation for transient pressure changes in BOG flow due to variations in operations.

Abstract: Disclosed are a method and an apparatus for treating boil-off gas generated in an LNG storage tank of an LNG carrier for transporting LNG in a cryogenic liquid state, the LNG carrier having a boil-off gas reliquefaction plant, wherein an amount of boil-off gas corresponding to a treatment capacity of the reliquefaction plant among the total amount of boil-off gas generated during the voyage of the LNG carrier is discharged from the LNG storage tank and reliquefied by the reliquefaction plant. The boil-off gas treating method and apparatus can maintain an amount of boil-off gas discharged from an LNG storage tank at a constant level by storing in the LNG storage tank, instead of discharging and burning, surplus boil-off gas which has not been returned to the LNG storage tank through the reliquefaction plant among the total amount of boil-off gas generated in the LNG storage tank, and can prevent waste of boil-off gas and save energy by allowing an internal pressure of the LNG storage tank to be increased.

Abstract: The superconducting device has a cryogenic system to whose first refrigerant there is thermally coupled a superconducting unit and a superconducting switching path, which is electrically connected to said unit and is to be activated thermally by a heater, of a superconducting switch. A first pipeline to whose end the superconducting switching path is thermally coupled is to be connected to a refrigerant space of the superconducting unit. In order to ensure reliable heating of the switching path upon activation of the heater, the first pipeline is to have a cross sectional constriction impeding the exchange of heat with the refrigerant space. Moreover, the switching path is to be thermally coupled to a comparatively higher temperature level via a further, closed pipeline with a second refrigerant.

Abstract: A process is provided for recovering residual boil-off gas from LNG storage tanks at or near atmospheric pressure. Vaporized natural gas is recycled to an eductor to provide a motive force to withdraw residual boil-off gas in a container. The vapor is mixed with intermediate pressure LNG and sent to a vaporizer for down stream processing.

Abstract: Volatile vapors are removed from a storage vessel by establishing a flow of a stream of volatile vapors from the storage vessel and directing the stream through a first low temperature condenser for condensing a portion of the stream flowing through the first low temperature condenser. Since a portion of the condensed condensate freezes and causes a pressure drop in the first low temperature condenser, further steps may include directing the stream from the first low temperature condenser through a second low temperature condenser after the pressure drop exceeds a setpoint, stopping the flow of the refrigerant through the first low temperature condenser and using the heat of the volatile vapor stream to melt the frozen condensate in the first low temperature condenser. The stream is switched between the condensers as necessary to prevent excessive plugging due to frozen condensate formation. The system includes the means for implementing the method.

Abstract: A process for condensing a C3-C4 hydrocarbon vapor which comprises contacting the C3-C4 hydrocarbon vapor with a heat exchanger surface which is cooled by contact with LNG and recovering a liquefied C3-C4 product therefrom.

Abstract: The superconducting winding comprises a rotor which may rotate about a rotation axis with a superconducting winding in a thermally conducting winding support. The winding support comprises a central coolant cavity, with a lateral cavity leading out of the winding support connected thereto. A cold head of a refrigeration unit is connected to a condenser unit for condensing refrigerant and is arranged outside the rotor. A fixed heat tube, supplying the refrigerant, is coupled to the condenser unit, extending axially into the rotating lateral cavity and is sealed relative to the cavity. The refrigerant is a mixture of several components having different condensation temperatures.

Abstract: Apparatus and methods for improving the safety and efficiency and decreasing the cost of producing liquid gas, such as liquid oxygen, with a small-scale use liquefaction device, according to various embodiments of the present invention. In one embodiment, liquid oxygen barrier may be added to interface between a cryocooler and a dewar to control rate of liquid oxygen escape upon a tipping of the dewar. A boiloff vessel in fluid communication with the dewar allows expanding gas from a tipped dewar to escape while allowing the liquid to safely settle in the boiloff vessel. A temperature sensing circuit, in proximity with a heat dissipator or cold finger of the cryocooler, is operable to break an electrical power circuit of the cryocooler or cooling fan when a sensed temperature exceeds a predetermined temperature. Oxygen purity of a feed stream of gas may be sensed and/or displayed.

Abstract: A refrigeration system especially useful for refrigerating biological samples wherein a cryocooler, such as one employing a pressure wave from a pressure wave generator, is used to generate refrigeration for cooling liquid coolant or purging fluid, which is employed within hollow structures bordering an enclosed space of a storage unit or within the storage space of a storage unit and is subsequently cleaned of contaminants purged from the storage space.

Abstract: A batch process and apparatus for producing a pressurized liquid carbon dioxide stream includes distilling a feed stream of carbon dioxide vapor off of a liquid carbon dioxide supply; introducing the carbon dioxide vapor feed stream into at least one purifying filter; condensing the purified feed stream within a condenser to form an intermediate liquid carbon dioxide stream; introducing the intermediate liquid carbon dioxide stream into at least one high-pressure accumulation chamber; heating the high pressure accumulation chamber to pressurize the liquid carbon dioxide contained therein to a delivery pressure; delivering a pressurized liquid carbon dioxide stream from the high-pressure accumulation chamber; and, discontinuing delivery of the pressurized liquid carbon dioxide stream for replenishing the high pressure accumulation chamber.

Abstract: Recovered, compressed VOC gas is used as fuel for a steam system where the steam produced is used for the operation of one or more compressors (26,28,30) that are used for the compression of the VOC gas.

Abstract: In a device for the re-condensation of low-boiling gases evaporating from a liquid gas container having a tubular neck in which a cold head of a cryo-generator is supported, the cold head includes a pulse tube with a heat exchanger and a cold area having an annular projection extending into an annular recess formed in a heat transfer ring mounted in the tubular neck in closely spaced relationship with the walls of the annular recess so as to provide a gas passage therethrough and permitting relative axial movement between the cold head and the liquid gas container.

Abstract: Supply of liquefied gases. The plant is characterized in that: *the withdrawal outlet is provided with a transfer pump (16) and with an ejector (17) which are located upstream of the fitting (11); *the ullage space of the container is equipped with a gas phase recycling line (5) equipped with a fitting (15); and * heat exchange means (19) are interposed in order to:—condense all or a portion of the recycled gas phase from the container and reinject it in liquid form into the ejector where any further condensation is completed,—vaporize a portion of the liquid phase from the tank in order to maintain the gas phase occupying the ullage space of the latter. Application to the filling of several containers by a mobile tank.

Abstract: An apparatus for controlling the pressure in a cargo tank 1 supplies BOG generated from liquefied natural gas stored in the cargo tank 1 to a burning system 6 through a compressor. In this apparatus, a reliquefaction plant 5 is disposed on the downstream side of first and second compressors 3 and 4 and on the upstream side of the cargo tank 1 so that BOG discharged from the second compressor 4 is liquefied by the reliquefaction plant 5 and the liquefied fluid is returned again into the cargo tank 1.

Abstract: Recovered, compressed VOC gas is used as fuel for a steam system where the steam produced is used for the operation of one or more compressors (26,28,30) that are used for the compression of the VOC gas.

Abstract: Gas condenser (2) arranged to condense gas/vapour (4) evaporating from a volatile liquid (6) being stored, for example, in a storage tank. The gas/vapour (4) is conducted into a gas chamber (16) provided with openings, possibly also nozzles (76), the gas chamber (16) being placed in a surrounding housing (36). Thereafter, the gas/vapour (4) is sucked into at least one venturi section (62, 64), wherein the liquid (6), for example, is flowing with a static underpressure relative to the inflowing gas/vapour (4). Via at least one expansion section (88, 90), a mixture (92) of gas/vapour (bubbles) (4) and liquid (6) flows onward to a condensing chamber (98), through which the static pressure of the liquid (6) increases and the gas/vapour (4) is condensed, after which the mixture (92) is conducted back to, for example, the storage tank.

Abstract: Supply of liquefied gases. The plant is characterized in that: *the withdrawal outlet is provided with a transfer pump (16) and with an ejector (17) which are located upstream of the fitting (11); *the ullage space of the container is equipped with a gas phase recycling line (5) equipped with a fitting (15); and * heat exchange means (19) are interposed in order to: —condense all or a portion of the recycled gas phase from the container and reinject it in liquid form into the ejector where any further condensation is completed, —vaporize a portion of the liquid phase from the tank in order to maintain the gas phase occupying the ullage space of the latter. Application to the filling of several containers by a mobile tank.

Abstract: In a device for the re-condensation of low-boiling gases evaporating from a liquid gas container having a tubular neck in which a cold head of a cryo-generator is supported, the cold head includes a pulse tube with a heat exchanger and a cold area having an annular projection extending into an annular recess formed in a heat transfer ring mounted in the tubular neck in closely spaced relationship with the walls of the annular recess so as to provide a gas passage therethrough and permitting relative axial movement between the cold head and the liquid gas container.

Abstract: A process for ethane extraction from a gas stream based on turboexpansion and fractionation with no mechanical refrigeration is provided. The feed gas is sweetened and dehydrated by a conventional amine process and by a molecular sieve unit, to remove carbon dioxide and water. After this pretreatment, the feed gas undergoes to a series of cooling steps through a cryogenic brazed aluminum heat exchanger and fed to a demethanizer column. A stream rich in methane is recovered from the top of this column and fed to a centrifugal compressor and subsequently routed to a booster/turboexpander. The temperature of the methane gas is greatly reduced by the expansion allowing the cooled methane stream to be a cooling source for cryogenic heat exchanger. Feed for a de-ethanizer column comes from the bottom liquids of the de-methanizer column. Ethane is recovered overhead at the de-ethanizer column.

Abstract: An apparatus for re-liquefying boil-off gas produced by liquid natural gas is described. The apparatus is made up of a collector, wherein the collector contains liquid natural gas, at least one first pump, wherein the first pump is in or adjacent to the liquid natural gas collector, a compressor, wherein the compressor communicates with the liquid natural gas (LNG) collector by a first conduit, at least one mixing device, wherein the mixing device communicates with the compressor by a second conduit, and wherein the mixing device communicates with the first pump by a third conduit, at least one separating device, wherein the separating device communicates with the mixing device by a fourth conduit, and wherein the separating device also communicates with the liquid natural gas (LNG) collector by a fifth conduit.

Abstract: A pressure control device of a cargo tank (1) for supplying the BOG of the stored liquefied natural gas producing inside the cargo tank to a incineration treating system (6) through compressors so as to control a pressure in the cargo tank (1), wherein a re-liquefying device (5) is disposed on the downstream side of the first and second compressors (3, 4), i.e.

Abstract: A process is provided for converting a boil-off stream comprising methane to a liquid having a preselected bubble point temperature. The boil-off stream is pressurized, then cooled, and then expanded to further cool and at least partially liquefy the boil-off stream. The preselected bubble point temperature of the resulting pressurized liquid is obtained by performing at least one of the following steps: before, during, or after the process of liquefying the boil-off stream, removing from the boil-off stream a predetermined amount of one or more components, such as nitrogen, having a vapor pressure greater than the vapor pressure of methane, and before, during, or after the process of liquefying the boil-off stream, adding to the boil-off stream one or more additives having a molecular weight heavier than the molecular weight of methane and having a vapor pressure less than the vapor pressure of methane.

Abstract: To provide a preserving system capable of re-using vaporized nitrogen, and moreover, capable of always cooling the specimens at a predetermined temperature or lower. The preserving system comprising a cylinder and the preserving vessel which is supplied with liquid nitrogen from this cylinder, is provided with a Stirling refrigerator and a condensing chamber arranged outside of said preserving vessel, and the gas phase part of this condensing chamber is made to communicate with that of said preserving vessel and also the liquid phase part is made to communicate with that of said preserving vessel, and further the cooling part of said Stirling refrigerator is arranged in said condensing chamber, therefore, the nitrogen vaporized in the preserving vessel is cooled by the cooling part of the Stirling refrigerator in the condensing chamber and liquefied again, and so this liquid nitrogen can be reused for cooling the preserving vessel.

Abstract: A process and apparatus for exploitation and liquefaction of natural gas in offshore stranded gas reserves. Two ordinary nautical vessels are used to produce, store and unload LPG and LNG. Typical front end processing is performed on the first vessel. The treated inlet gas is transported to the second vessel where the stream goes through liquefaction and storage until it is offloaded to a transport vessel for shipment. The liquefaction process utilizes two refrigerant cycles that utilize two expanded refrigerants, at least one of which is circulated in a gas phase refrigeration cycle. The refrigerants and the inlet gas stream are transported between the two vessels by the use of piping. Electricity can be generated to provide power for the compression sections of the refrigeration cycles. Turbines, engines, or boilers from the vessels can be used for generating electricity since they are no longer needed for locomotion purposes.

Abstract: A process is provided for converting a boil-off stream comprising methane to a liquid having a preselected bubble point temperature. The boil-off stream is pressurized, then cooled, and then expanded to further cool and at least partially liquefy the boil-off stream. The preselected bubble point temperature of the resulting pressurized liquid is obtained by performing at least one of the following steps: before, during, or after the process of liquefying the boil-off stream, removing from the boil-off stream a predetermined amount of one or more components, such as nitrogen, having a vapor pressure greater than the vapor pressure of methane, and before, during, or after the process of liquefying the boil-off stream, adding to the boil-off stream one or more additives having a molecular weight heavier than the molecular weight of methane and having a vapor pressure less than the vapor pressure of methane.

Abstract: A system stores densely dissolved methane-base gas and supplies gas of a predetermined composition. A container (10) stores methane-base gas dissolved in hydrocarbon solvent and supplies it to means for adjusting composition, through which an object of regulated contents is obtained. Preferably, the means for adjusting composition is means for maintaining the tank in a supercritical state, or piping (48) for extracting substances at a predetermined ratio from the gas phase (12) and liquid phase (16) in the container.