Abstract: Embodiments of this invention relate to a process for liquefaction of natural gas and other methane-rich gas streams, and more particularly to a process for producing liquefied natural gas (LNG). In a first step of the process, a first fraction of the feed gas is withdrawn, compressed to a pressure greater than or equal to 1500 psia, cooled and expanded to a lower pressure to cool the withdrawn first fraction. The remaining fraction of the feed stream is cooled by indirect heat exchange with the expanded first fraction in a first heat exchange process. In a second step a separate stream comprising flash vapor is compressed, cooled and expanded to a lower pressure providing another cold stream. This cold stream is used to cool the remaining feed gas stream in a second indirect heat exchange process. The expanded stream exiting from the second heat exchange process is used for supplemental cooling in the first indirect heat exchange step.

Abstract: A vessel for transporting liquefied natural gas is provided. The vessel generally includes a gas transfer system for on-loading and off-loading natural gas to and from the vessel at essentially ambient temperature. The vessel further includes a gas processing facility for selectively providing liquefaction and regasification of the natural gas. The vessel also includes a containment structure for containing the liquefied natural gas during transport. The vessel may be a marine vessel or a barge vessel for transporting LNG over water, or a trailer vessel for transporting LNG overthe-road. A method for transporting LNG is also provided, that provides on-loading of natural gas onto a vessel, condensing the natural gas, storing the gas on the vessel in liquefied form, transporting the gas to an import terminal, vaporizing the gas, and off-loading the gas at the terminal.

Abstract: Containers suitable for storing pressurized fluids at cryogenic temperatures of ?62° C. (?80° F.) and colder are provided and comprise a self-supporting liner and load-bearing composite overwrap, whereby means are provided for substantially preventing failure of the container during temperature changes.

Abstract: Methods for producing toughness-optimized weld joints are provided. A welding procedure that will provide adequate toughness for the center-weld of the weld-joint is developed and used, and a welding procedure that will provide adequate toughness for the surface-weld of the weld-joint is developed and used.

Abstract: Improved systems and methods for transporting fluids in containers are provided. Such improved systems and methods include floatable container vessels having one or more fluid containers and self-propelled marine transportation vessels that are adapted to be ballasted downwardly to permit the floatable container vessels to be floated onto or off of the marine transportation vessels, and are adapted to be deballasted so as to raise the floatable container vessels out of the water for transportation to another location.

Abstract: Fuel storage and delivery systems for compressed natural gas are provided that are constructed from ultra-high strength, low alloy steels containing less than 2.5 wt % nickel and having a tensile strength greater than 900 MPa (130 ksi). A primary benefit is that systems of this invention have substantially lower weight than that of currently available steel-based systems. Consequently, the fuel efficiency of a CNG vehicle can be improved due to the lower weight of the system of this invention, or the driving range of the CNG vehicle can be improved by increased fuel storage for the same volume at an elevated pressure, or the load-carrying capacity of the CNG vehicle can be improved. Another primary benefit is that systems of this invention have a cost per unit strength substantially lower than that of currently available systems.

Abstract: Offshore facilities and methods are provided to enable the mooring of a ship carrying a liquefied gas to an offshore structure with one or more decks upon which are located (i) regasification facilities; (ii) single point mooring means for mooring a ship that is carrying a liquefied gas; (iii) means for offloading said liquefied gas into said regasification facilities; and (iv) means for transferring gas from said regasification facilities to a gas transport pipeline.

Abstract: This invention is a method and apparatus for production of pressurized liquefied gas. First, a gas stream is cooled and expanded to liquefy the gas stream. The liquefied gas stream is then withdrawn as pressurized gas product and a portion is recycled through the heat exchanger to provide at least part of the cooling and is returned to the stream. Recycling the pressurized liquefied gas product helps keep the cooling and compression of the gas stream in the supercritcal region of the phase diagram. J-T valves in parallel with the expander permits running the system until the stream is in the supercritical region of its phase diagram and the hydraulic expander can operate. This process is suitable for natural gas streams containing methane to form a pressurized liquefied natural gas (PLNG) product.

Abstract: A process is provided for converting a pressurized methane-rich vapor at a first pressure to a predetermined second pressure higher than the first pressure. A pressurized liquid rich in methane is passed to an eductor to provide the motive energy for driving the eductor. The methane-rich vapor is passed to the eductor and mixed with the liquid.

Abstract: Methods for producing toughness-optimized weld joints are provided. A welding procedure that will provide adequate toughness for the center-weld of the weld-joint is developed and used, and a welding procedure that will provide adequate toughness for the surface-weld of the weld-joint is developed and used.

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 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: Containers suitable for storing pressurized fluids at cryogenic temperatures of −62° C. (−80° F.) and colder are provided and comprise a self-supporting liner and load-bearing composite overwrap, whereby means are provided for substantially preventing failure of the container during temperature changes.

Abstract: This invention is a method and apparatus for production of pressurized liquefied gas. First, a gas stream is cooled and expanded to liquefy the gas stream. The liquefied gas stream is then withdrawn as pressurized gas product and a portion is recycled through the heat exchanger to provide at least part of the cooling and is returned to the stream. Recycling the pressurized liquefied gas product helps keep the cooling and compression of the gas stream in the supercritcal region of the phase diagram. J-T valves in parallel with the expander permits running the system until the stream is in the supercritical region of its phase diagram and the hydraulic expander can operate. This process is suitable for natural gas streams containing methane to form a pressurized liquefied natural gas (PLNG) product.

Abstract: Offshore facilities and methods are provided to enable the mooring of a ship carrying a liquefied gas to an offshore structure with one or more decks upon which are located (i) regasification facilities; (ii) single point mooring means for mooring a ship that is carrying a liquefied gas; (iii) means for offloading said liquefied gas into said regasification facilities; and (iv) means for transferring gas from said regasification facilities to a gas transport pipeline.

Abstract: Fuel storage and delivery systems for compressed natural gas are provided that are constructed from ultra-high strength, low alloy steels containing less than 2.5 wt % nickel and having a tensile strength greater than 900 MPa (130 ksi). A primary benefit is that systems of this invention have substantially lower weight than that of currently available steel-based systems. Consequently, the fuel efficiency of a CNG vehicle can be improved due to the lower weight of the system of this invention, or the driving range of the CNG vehicle can be improved by increased fuel storage for the same volume at an elevated pressure, or the load-carrying capacity of the CNG vehicle can be improved. Another primary benefit is that systems of this invention have a cost per unit strength substantially lower than that of currently available systems.

Abstract: The invention is an absorption process for recovering C2+ components from a pressurized liquid mixture comprising C1 and C2+. The pressurized liquid mixture is at least partially vaporized by heating the liquid mixture in a heat transfer means. The heat transfer means provides refrigeration to an absorption medium that is used in treating the vaporized mixture in an absorption zone. The vaporized mixture is passed to an absorption zone that produces a first stream enriched in C1 and a second stream enriched in C2+ components. The pressurized liquid mixture is preferably pressurized liquid natural gas (PLNG) having an initial pressure above about 1,724 kPa (250 psia) and an initial temperature above −112° C. (−170° F.). Before being vaporized, the pressurized liquid mixture is preferably boosted in pressure to approximately the desired operating pressure of the absorption zone.

Abstract: Systems and methods are provided for delivering pressurized liquefied natural gas to an import terminal equipped with containers and vaporization facilities suitable for conventional LNG.

Abstract: The invention relates to a process of manufacturing a pressurized multi-component liquid from a pressurized, multi-component stream, such as natural gas, which contains C5+ components and at least one component of C1, C2, C3, or C4. The process selectively removes from the multi-component stream one or more of the C5+ components that would be expected to crystallize at the selected temperature and pressure of the pressurized multi-component liquid product and leaves in the multi-component stream at least one C5+ component. The multi-component stream is then liquefied to produce a pressurized liquid substantially free of crystallized C5+ components. The removal of the C5+ components can be by selective fractionation or crystallization.

Abstract: The invention is an absorption process for recovering C2+ components from a pressurized liquid mixture comprising C1 and C2+. The pressurized liquid mixture is at least partially vaporized by heating the liquid mixture in a heat transfer means. The heat transfer means provides refrigeration to an absorption medium that is used in treating the vaporized mixture in an absorption zone. The vaporized mixture is passed to an absorption zone that produces a first stream enriched in C1 and a second stream enriched in C2+ components. The pressurized liquid mixture is preferably pressurized liquid natural gas (PLNG) having an initial pressure above about 1,724 kPa (250 psia) and an initial temperature above −112° C. (−170° F.). Before being vaporized, the pressurized liquid mixture is preferably boosted in pressure to approximately the desired operating pressure of the absorption zone.