Abstract: A method and apparatus for processing natural gas composed of various hydrocarbon components for transportation of the natural gas to a demand side without separation of the hydrocarbon components, such that the natural gas can be used by consumers after being separated into the hydrocarbon components according to the needs of the demand side. The apparatus includes a storage tank and a hydrocarbon liquefied gas mixture accommodated in the storage tank. The mixture has hydrocarbon components composed of methane, ethane, propane and butane, and is produced by liquefying raw natural gas without changing the relative ratio of methane, ethane, propane and butane in the raw natural gas immediately after extraction from the gas well. The method and apparatus can be applied to floating marine structures.

Abstract: An improved method is provided for removing contaminants from a hydrocarbon stream, such as a stream of raw natural gas. The contaminated hydrocarbon stream is passed through a first adsorbent bed containing molecular sieves to adsorb contaminants on the molecular sieves, thereby removing at least some of the contaminants from the hydrocarbon stream. The contaminated hydrocarbon stream may optionally be passed through a second adsorbent bed containing a desiccant material other than molecular sieves. The molecular sieves are regenerated using a wet regeneration process in which both the water content and temperature of the regeneration fluid stream are staged.

Abstract: The liquefaction method provides fractionation of the natural gas with ethane recycle in order to enhance propane recovery and to increase the critical pressure of the gas to be liquefied. The natural gas is partly liquefied by cooling in E1, then separated in fractionating column 2 into a methane-rich stream and a stream rich in hydrocarbons heavier than methane. The methane-rich stream is partly liquefied in 3, then the condensates separated in drum 4 are recycled to the top of column 2 through line 7. The gas fraction from drum 4 is liquefied in exchanger E2 to produce the liquefied natural gas. The stream rich in hydrocarbons heavier than methane is separated in the deethanizer into an ethane-enriched fraction and heavier hydrocarbons. According to the invention, the ethane-enriched fraction is at least partly liquefied, then part of the liquefied ethane is recycled to separating drum 4 or reflux line 7.

Abstract: Systems and methods for producing liquid natural gas from heat exchange with liquid nitrogen or air is provided. The produced liquid natural gas may be used as vehicle fuel. After heat exchange, the vaporized liquid nitrogen or air may be routed in the system to regenerate a heat exchange unit and/or a natural gas pretreatment unit. After assisting with the regeneration, the vaporized nitrogen or air may be safely vented to atmosphere. In one embodiment, a system for liquefying natural gas using a refrigerant includes a first treating unit configured to remove a contaminant from the natural gas; a first exchanger unit for liquefying the natural gas using the refrigerant; a second exchanger unit configured to receive the refrigerant from the first exchanger unit, wherein the first exchanger unit and the second exchanger unit operate on alternating cycles; a second treating unit configured to receive the refrigerant from the second exchanger unit; and a storage unit for the receiving the liquid natural gas.

Abstract: A floating system for liquefying natural gas comprising a vessel provided with a plant for liquefying natural gas having an inlet for natural gas and an outlet for liquefied natural gas, a feed supply system for supplying natural gas to the inlet of the plant, one or more storage tanks for storing liquefied natural gas, and an off-loading system for transporting liquefied natural gas between the storage tank(s) and a tanker, which floating system further comprises a vaporization system having an inlet for liquefied gas and an outlet for vapor.

Abstract: A turbo compressor train is provided. The turbo compressor train includes a turbo compressor unit and a drive assembly for driving the turbo compressor unit. The drive unit has a gas turbine and a generator and a steam turbine. The steam turbine may be coupled together with the generator to the turbo compressor unit and the gas turbine by means of a coupling device. The coupling device has an overrun coupling and a coupling exciter with which the overrun coupling may be taken from a disengaged condition to an active condition by engaging of the overrun coupling at synchronous speed of the gas turbine and the steam turbine and if the overrun coupling is engaged, disengages upon a speed increase to the steam turbine and generator so that the generator may be driven by the steam turbine at a higher speed than the turbocompressor unit by the gas turbine.

Abstract: A floating system for liquefying natural gas comprising a vessel provided with a plant for liquefying natural gas having an inlet for natural gas and an outlet for liquefied natural gas, a feed supply system for supplying natural gas to the inlet of the plant, one or more storage tanks for storing liquefied natural gas, and an off-loading system for transporting liquefied natural gas between the storage tank(s) and a tanker, which floating system further comprises a vaporization system having an inlet for liquefied gas and an outlet for vapour.

Abstract: A process for treating offshore natural gas includes processing the natural gas on an off-shore processing facility by, (i) liquefying and fractionating the natural gas to generate a liquefied natural gas stream and a higher hydrocarbon stream, (ii) vapourising at least a portion of the higher hydrocarbon stream, (iii) passing the vapourised higher hydrocarbon stream and steam over a steam reforming catalyst to generate a reformed gas mixture comprising methane, steam, carbon oxides and hydrogen, (iv) passing the reformed gas mixture over a methanation catalyst to generate a methane rich gas, and (v) combining the methane-rich gas with the natural gas prior to the liquefaction step.

Abstract: The invention provides a process for producing purified natural gas from feed natural gas comprising water and carbon dioxide, the process comprising the steps of: (a) removing water from the feed natural gas to obtain natural gas depleted in water and comprising carbon dioxide; (b) contacting the natural gas obtained in step (a) with solid sorbent comprising a metal organic framework to remove at least part of the carbon dioxide, thereby obtaining the purified natural gas.

Abstract: A method and apparatus for separating acid gas from a natural gas stream suitable for use on an offshore facility located on a platform or floating vessel are disclosed. The method includes the steps of: contacting the natural gas stream with a semi-lean amine solution in a static mixer to produce a rich amine solution, separating a first portion of carbon dioxide from the rich amine solution to produce the semi-lean amine solution, and heating a portion of the semi-lean amine solution to separate a second portion of carbon dioxide and produce the lean amine solution. The rich amine solution and semi-lean amine solution can be heated using recovered waste heat.

Abstract: A method of natural gas liquefaction may include cooling a gaseous NG process stream to form a liquid NG process stream. The method may further include directing the first tail gas stream out of a plant at a first pressure and directing a second tail gas stream out of the plant at a second pressure. An additional method of natural gas liquefaction may include separating CO2 from a liquid NG process stream and processing the CO2 to provide a CO2 product stream. Another method of natural gas liquefaction may include combining a marginal gaseous NG process stream with a secondary substantially pure NG stream to provide an improved gaseous NG process stream. Additionally, a NG liquefaction plant may include a first tail gas outlet, and at least a second tail gas outlet, the at least a second tail gas outlet separate from the first tail gas outlet.

Abstract: A method and apparatus are described to provide complete gas utilization in the liquefaction operation from a source of gas without return of natural gas to the source thereof from the process and apparatus. The mass flow rate of gas input into the system and apparatus may be substantially equal to the mass flow rate of liquefied product output from the system, such as for storage or use.

Abstract: A method of natural gas liquefaction may include liquefying natural gas from a first natural gas source with a first core module, and liquefying natural gas from at least a second natural gas source having a gas property different than a gas property of the first natural gas source with at least a second core module substantially identical to the first core module. Additionally, a method of designing a natural gas liquefaction plant may include utilizing a preconfigured core module design for a core module configured to receive source gas at site-independent predetermined input conditions, expel tail gas at site-independent predetermined outlet conditions, and liquefy natural gas. Furthermore, a method of distributing liquid natural gas may include providing a plurality of natural gas liquefaction plants comprising substantially identical core modules to a plurality of gaseous natural gas source locations.

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 condensed mixed hydrocarbon feed stream (10), recovered from an initial feed stream (8), is fractionated into one ore more fractionated streams. In this process, the condensed mixed hydrocarbon feed stream (10) is separated into at least a first part-feed stream (20) and a second part-feed stream (30). The first part-feed stream (20) is passed into a first gas/liquid separator (14), to provide at least a first fractionated stream in the form of a first gaseous overhead stream (40). A first bottom liquid stream (50) provided by the first gas/liquid separator (14) is passed into a second gas/liquid separator (22) to provide at least a second fractionated stream in the form of a second gaseous overhead stream (70), which is cooled by heat exchange (26) against the second part-feed stream (30).

Abstract: A method and apparatus for cooling a hydrocarbon stream such as natural gas. An initial hydrocarbon stream is passed through a first separator to provide an initial overhead stream and a mixed hydrocarbon feed stream. The initial overhead stream is cooled to provide a cooled hydrocarbon stream such as LNG, and at least a C1 overhead stream and one or more C2, C3 and C4 overhead streams are separated from the mixed hydrocarbon feed stream. At least a fraction of at least one of the group comprising: the C2 overhead stream, the C3 overhead stream and the C4 overhead stream is cooled with the C1 overhead stream to provide a cooled stream, which is further cooled against at least a fraction of the cooled, preferably liquefied, hydrocarbon stream to provide an at least partly liquefied cooled stream.

Abstract: An LNG carrier having an LNG loading and unloading system includes a submerged turret loading (STL) system for introducing and discharging a natural gas; a liquefaction plant for liquefying the natural gas introduced through the submerged turret loading system into a cryogenic liquefied natural gas; at least one self-supporting storage tank installed in the LNG carrier for storing the liquefied natural gas, the self-supporting storage tank arranged in such a manner that the liquefied natural gas is loaded to and unloaded from the LNG carrier through the self-supporting storage tank; and at least one membrane type storage tank arranged in a neighboring relationship with the self-supporting storage tank, the membrane type storage tank kept in fluid communication with the self-supporting storage tank. The LNG carrier further includes a regasification plant for regasifying the liquefied natural gas stored in the self-supporting storage tank.

Abstract: A system for extracting a target atmospheric gas from an atmosphere, including a carbon-neutral energy source and a cooling unit connected to a condenser, is disclosed. An optional collection chamber and optional reaction chamber are also disclosed. Also disclosed are a method of providing hydrocarbon feedstocks, a method of removing a gas from an atmosphere, and a method of reducing the concentration of the greenhouse gas carbon dioxide in the earth's atmosphere.

Abstract: A semi-closed loop system for producing liquefied natural gas (LNG) that combines certain advantages of closed-loop systems with certain advantages of open-loop systems to provide a more efficient and effective hybrid system. In the semi-closed loop system, the final methane refrigeration cycle provides significant cooling of the natural gas stream via indirect heat transfer, as opposed to expansion-type cooling. A minor portion of the LNG product from the methane refrigeration cycle is used as make-up refrigerant in the methane refrigeration cycle. A pressurized portion of the refrigerant from the methane refrigeration cycle is employed as fuel gas. Excess refrigerant from the methane refrigeration cycle can be recombined with the processed natural gas stream, rather than flared.

Abstract: A process is provided which includes: bringing a natural gas, e.g., methane gas or propane gas, or a mixture of these gases into gas-liquid contact with raw-material water to form a gas hydrate; compression-molding the gas hydrate into pellets; and cooling/depressurizing the pellets. Also provided is an apparatus for use in the process. In the cooling/depressurizing step 4, molded gas hydrate masses h3 in a pressurized state are cooled and depressurized to a downstream-side pressure. In the cooling/depressurizing step 4, a receiving chamber 15 which accommodates the gas hydrate masses h3 obtained in the molding step 3 is provided, and the masses h3 are depressurized to the downstream-side pressure while passing through the receiving chamber 15. The masses h3 are introduced into and immersed in a liquid refrigerant r packed in the receiving chamber 15 so that the masses h3 are cooled by solid/liquid contacting with the liquid refrigerant r.

Abstract: A condenser and a containment vessel adapted to efficiently condense a gas out of a mixture of condensing and non-condensing gases. In condensers, the fraction of gas within a condenser made up of non-condensing gases can be significantly reduced by withdrawing gas from localised regions of relatively low temperature where the mass fraction of non-condensing gases will be relatively high. In containment vessels, pressures can be reduced by providing a large surface area of the liquid into which the condensing gas condenses in a relatively cool region of the containment vessel. Both these effects result from an appreciation of the manner in which non-condensing gases tend to accumulate in regions which are relatively cold.

Abstract: A method for the uninterrupted operation of a gas liquefaction system is provided, wherein the operation is continuously monitored for at least those users of the refrigerant compressor component which represent a two-digit percentage of the total load on the refrigerant compressor component. A total instantaneously available negative load reserve is calculated, and at least one predetermined turbine is switched off when the load reserve reachable via a frequency regulation of the one or more refrigerant compressors is lower than the energy demand of the largest of the refrigerant compressors and either a refrigerant compressor fails or a speed of frequency change for the power supply network for the gas liquefaction system exceeds a present threshold.

Abstract: Produced natural gas containing carbon dioxide is dehydrated and chilled to liquefy the carbon dioxide and then fractionated to produce a waste stream of liquid carbon dioxide and hydrogen sulfide. Natural gas liquids may be first separated and removed before fractionation. After fractionation, the waste stream is pressurized and transmitted to a remote injection well for injection either for disposal of the waste stream and preferably to urge hydrocarbons toward the producing well. A hydrocarbon stream proceeds from fractionation to a methanol absorber system which removes carbon dioxide gas. The hydrocarbon stream is thereafter separated into at least hydrocarbon gas, nitrogen and helium. Some of the nitrogen is reintroduced into a fractionation tower to enhance the recovery of hydrocarbons. A methanol recovery system is provided to recover and reuse the methanol. The hydrocarbons are sold as natural gas and the helium is recovered and sold. Excess nitrogen is vented.

Abstract: A trap system for cryogenic environments, which brings a gas to a body of the same material in liquid form, allows the liquefied material in the gas bearing tube to pass through a submerged trap combining the newly condensed liquid with that in the reserve. With this apparatus, for example, pure cold Nitrogen gas can be condensed and recycled in a system requiring cryogenic liquid Nitrogen to start the process. This trap system can also be applied to other gaseous materials stored cooled beyond the condensing temperatures. The trap system brings the newly condensed material into the vessel of already condensed material. The gas that has not condensed into liquid, in the case of Liquid Nitrogen, will release into the atmosphere. It is expected that all the gas of the other material will liquefy and be part of the stored liquid because it is stored below its liquefaction temperature—here using Liquid Nitrogen chambers surrounding the vessel of the liquefied material.

Abstract: A process for recovery of natural gas liquids is disclosed, the process including: fractionating a gas stream comprising nitrogen, methane, ethane, and propane and other C3+ hydrocarbons into at least two fractions including a light fraction comprising nitrogen, methane, ethane, and propane, and a heavy fraction comprising propane and other C3+ hydrocarbons; separating the light fraction into at least two fractions including a nitrogen-enriched fraction and a nitrogen-depleted fraction in a first separator; separating the nitrogen-depleted fraction into a propane-enriched fraction and a propane-depleted fraction in a second separator; feeding at least a portion of the propane-enriched fraction to the fractionating as a reflux; recycling at least a portion of the propane-depleted fraction to the first separator. In some embodiments, the nitrogen-enriched fraction may be separated in a nitrogen removal unit to produce a nitrogen-depleted natural gas stream and a nitrogen-enriched natural gas stream.

Abstract: A process and also an arrangement for disposing of one of more carbon dioxide-containing fractions which occur at one or more sites of a fractionation and/or liquefaction process such as, for example, a natural gas liquefaction process. The carbon dioxide-containing fraction(s) is or are subjected to a purification (B) and/or liquefaction (C) and subsequently sequestered (D). Preferably, use is made of at least one substream (6) of the liquefied carbon dioxide-containing fraction(s) as refrigerant (D) within the fractionation and/or liquefaction process.

Abstract: Apparatuses and methods are provided for producing liquefied gas, such as liquefied natural gas. In one embodiment, a liquefaction plant may be coupled to a source of unpurified natural gas, such as a natural gas pipeline at a pressure letdown station. A portion of the gas is drawn off and split into a process stream and a cooling stream. The cooling stream may sequentially pass through a compressor and an expander. The process stream may also pass through a compressor. The compressed process stream is cooled, such as by the expanded cooling stream. The cooled, compressed process stream is expanded to liquefy the natural gas. A gas-liquid separator separates the vapor from the liquid natural gas. A portion of the liquid gas may be used for additional cooling. Gas produced within the system may be recompressed for reintroduction into a receiving line.

Abstract: The present invention relates to a method of treating a hydrocarbon stream, the method at least comprising the steps of: supplying a partly condensed feed stream (10). to a first gas/liquid separator (2) and into a gaseous stream (2 and a liquid stream (30); expanding the liquid stream (30) and the gaseous stream (20) and subsequently feeding them into a second gas/liquid separator (3) at a first and second feeding point (32) respectively, the second feeding point (32) being at a higher level than the first feeding point (31); feeding a liquefied natural gas stream (70,70b) into the second gas/liquid separator (3) at a third feeding point (33) being at a higher level than the second feeding point (32); removing from the top of the second gas/liquid separator (3) a C2+ lean gaseous stream (60) and from the bottom a liquid stream (80, 80a); wherein the liquefied ?natural gas stream (70,70b) is obtained from a source (4) of liquefied natural gas from a separate plant.

Abstract: A method and system for optimizing the efficiency of an LNG liquification system of the gas expansion type, wherein an incoming feed gas is first separated in a fractionation column by counter current contact with a cold reflux fluid, and a gaseous stream introduced into the heat exchanger system at a reduced temperature such that an intermediate pinch point is created in the warm composite curve.

Abstract: Systems and methods of driving a compressor are provided. The compressor can be driven by multiple electric motors, which can be controlled by an adjustable speed drive (ASD) to increase efficiency. A torque controller may also be included.

Abstract: A method is described for production of LNG from an incoming feed gas (1) on an onshore or offshore installation, and it is characterised by the following steps: 1) the feed gas is led through a fractionation column (150) where it is cooled a separated in an overhead fraction with a reduced content of pentane (C5) and heavier components, and a bottom fraction enriched with heavier hydrocarbons, 2) the overhead fraction from the fractionation column is fed to a heat exchanger system (110) and is subjected to a partial condensation to form a two-phase fluid, and the two-phase fluid is separated in a suitable separator (160) a liquid (5) rich in LPG and pentane (C3-C5) which is re-circulated as cold reflux to the fractionation column (150), while the gas (6) containing lower amounts of C5 hydrocarbons and hydrocarbons heavier than C5 is exported for further processing in the heat exchanger system (110) for liquefaction to LNG with a maximum content of ethane and LPG 3) the cooling circuit for liquefaction of gas

Abstract: A natural gas liquid plant includes a separator (103) that receives a cooled low pressure feed gas (4), wherein the separator (103) is coupled to an absorber (108) and a demethanizer (110). Refrigeration duty of the absorber (108) and demethanizer (110) are provided at least in part by expansion of a liquid portion of the cooled low pressure feed gas (4) and an expansion of a liquid absorber bottom product (19), wherein ethane recovery is at least 85 mol % and propane recovery is at least 99 mol %. Contemplated configurations are especially advantageous as upgrades to existing plants with low pressure feed gas where high ethane recovery is desirable.

Abstract: A method for treating a gas mixture containing acid gases is provided, comprising: contacting the gas mixture with an absorbing solution, by means of which a de-acidified gas mixture and an absorbing solution loaded with acid gases may be obtained; and regenerating the absorbing solution loaded with acid gases; wherein the regeneration comprises the following steps: passing the absorbing solution into a first regenerator at a first pressure; and then passing the absorbing solution into a second regenerator at a second pressure, less than the first pressure; and compressing the gases from the second regenerator and recycling the thereby compressed gases to the first regenerator, subsequent to passing into the second regenerator, passing the absorbing solution into a third regenerator at a third pressure less than the second pressure; and compressing the gases from the third regenerator and recycling the thereby compressed gases to the second regenerator; and wherein at least a portion of the gases from the

Abstract: The subject of the invention is a method for treating a natural gas containing ethane, comprising the following stages: (a) extraction of at least one part of the ethane from the natural gas; (b) reforming of at least one part of the extracted ethane into a synthesis gas; (c) methanation of the synthesis gas into a methane-rich gas; and (d) mixing of the methane-rich gas with the natural gas. Installation for implementing this method.

Abstract: A system for liquefying natural gas that includes a process and apparatus for enhancing the performance of one or more gas turbines. Gas turbine power output can be stabilized or even enhanced using the interstage cooling system configured according to one or more embodiments of the present invention. In one embodiment, partially compressed air from a lower compression stage of a gas turbine is cooled via indirect heat exchange with a primary coolant before being returned to a higher compression stage of the same gas turbine. Optionally, the interstage cooling system can employ one or more secondary coolants to remove the rejected heat from the primary coolant system.

Abstract: A hydrocarbon stream (30), such as natural gas, is commonly cooled together with a first refrigerant stream (140), against an evaporating refrigerant (24) in a series of one or more consecutively arranged common heat exchangers (2), which comprises a first common heat exchanger, upstream of which first common heat exchanger the hydrocarbon stream (10) and the first refrigerant stream (130) are not commonly cooled (4, 3). The hydrocarbon stream to be cooled is fed into the first common heat exchanger at a hydrocarbon feeding temperature, while the first refrigerant stream is fed into the first common heat exchanger at a refrigerant feeding temperature. The temperature difference between the hydrocarbon feeding temperature and the refrigerant feeding temperature is lower than 60-C.

Abstract: This invention provides a means of loading, processing and conditioning raw production gas, production of CGL, storage, transport, and delivery of pipeline quality natural gas or fractionated products to market. The CGL transport vessel utilizes a pipe based containment system to hold more densely packed constituents of natural gas held within a light hydrocarbon solvent than it is possible to attain for natural gas alone under such conditions. The containment system is supported by process systems for loading and transporting the natural gas as a liquid and unloading the CGL from the containment system and then offloading it in the gaseous state. The system can also be utilized for the selective storage and transport of NGLs to provide a total service package for the movement of natural gas and associated gas production. The mode of storage is suited for both marine and land transportation and configured in modular form to suit a particular application and/or scale of operation.

Abstract: The present invention provides a method of liquefying a hydrocarbon stream such as natural gas, the method at least comprising the steps of: (a) providing a hydrocarbon stream (10) at a first location (2), wherein the first location is situated onshore; (b) treating the hydrocarbon stream (10) in the first location (2) thereby obtaining a treated hydrocarbon stream (20); (c) transporting the treated hydrocarbon stream (20) via a pipeline (4) over a distance of at least 2 km to a second location (3), wherein the second location is situated off-shore; (d), liquefying the treated, hydrocarbon stream (20) at the second location (3) thereby obtaining liquefied hydrocarbon product (50) at atmospheric pressure.

Abstract: Apparatuses and methods are provided for producing liquefied gas, such as liquefied natural gas. In one embodiment, a liquefaction plant may be coupled to a source of unpurified natural gas, such as a natural gas pipeline at a pressure letdown station. A portion of the gas is drawn off and split into a process stream and a cooling stream. The cooling stream may sequentially pass through a compressor and an expander. The process stream may also pass through a compressor. The compressed process stream is cooled, such as by the expanded cooling stream. The cooled, compressed process stream is expanded to liquefy the natural gas. A gas-liquid separator separates the vapor from the liquid natural gas. A portion of the liquid gas may be used for additional cooling. Gas produced within the system may be recompressed for reintroduction into a receiving line.

Abstract: Disclosed is a process for liquefying natural gas wherein an available methane-rich feed, i.e., natural gas, at an excess pressure is initially expanded to provide expansion work which may be utilized in a number of novel ways, such as to provide refrigeration in a refrigerant cycle used to cool the feed or in one or more refrigerant cycles used in a liquefaction zone to liquefy the feed, or to generate electrical power for use in the liquefaction process or for export. In one embodiment, the expansion work is obtained by use of an expander/compressor device (turboexpander) which expands the feed to (1) drive the compressor of the device and thereby provide compression for a closed loop propane refrigeration cycle to pre-cool the natural gas stream, and (2) produce an expanded, chilled natural gas feed for a liquefaction process.

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 natural gas liquefaction system employing a high pressure pre-cooling refrigeration cycle. The natural gas liquefaction system can be advantageously employed in cold weather regions and/or in regions that exhibit large variations in ambient temperature.

Abstract: An apparatus and method for producing liquefied natural gas. A liquefaction plant may be coupled to a source of unpurified natural gas, such as a natural gas pipeline at a pressure letdown station. A portion of the gas is drawn off and split into a process stream and a cooling stream. The cooling stream passes through an expander creating work output. A compressor may be driven by the work output and compresses the process stream. The compressed process stream is cooled, such as by the expanded cooling stream. The cooled, compressed process stream is divided into first and second portions with the first portion being expanded to liquefy the natural gas. A gas-liquid separator separates the vapor from the liquid natural gas. The second portion of the cooled, compressed process stream is also expanded and used to cool the compressed process stream.

Abstract: Cascade-type natural gas liquefaction methods and apparatus are provided, having enhanced thermodynamic efficiencies, through the use of added refrigeration levels in one or both of the ethylene and methane refrigeration systems thereof.

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: An electronic HEMD determines the optimum balance between gas cooling and heat exchanger pressure loss, for any given operating condition, and adjusts the gas flow rate through the exchanger accordingly, to yield the maximum net power savings (and thereby energy savings) afforded by the exchanger. Maintaining the optimum balance between cooling and exchanger pressure loss reduces the amount of energy required to transport a given volume of gas through a pipeline and thereby increases the transmission efficiency of the gas pipeline system. A method of operating a heat exchanger on a natural gas transmission pipeline using a control algorithm that in turn controls the position of a heat exchanger bypass valve.

Abstract: The present invention provides a method of natural gas, the method at least comprising the steps of: (a) providing a natural gas stream (10) at a first location (2); (b) treating the natural gas stream (10) in the first location (2) thereby obtaining a treated natural gas stream (20), wherein the treated natural gas stream comprises in the range of from 70 to 100 mole % of methane; (c) transporting the treated natural gas stream (20) via a pipeline (4) over a distance of at least 2 km to a second location (3); (d) liquefying the treated natural gas stream (20) at the second location (3) thereby obtaining liquefied hydrocarbon product (50) at atmospheric pressure.

Abstract: A process for treating a crude containing natural gas comprising supplying the crude to a stabilization unit to obtain a gaseous stream and crude oil; supplying a compressed, gaseous stream at a low temperature to the bottom of a first column; partly condensing the first gaseous overhead stream, returning the liquid phase to the first column and supplying the methane-rich stream to a liquefaction plant; supplying an expanded bottom stream at a low temperature to the top of a second column; removing from the top of the second column a second gaseous overhead stream, and removing from the bottom of the second column a liquid bottom stream; vaporizing part of the bottom stream and introducing the vapor into the bottom of the second column; and introducing the remainder of the bottom stream into a crude oil stream at an appropriate point in or upstream of the stabilization unit, wherein the amount of heat removed from the first gaseous overhead stream is so adjusted that the concentration of C5+ in the first gase

Abstract: In this process, the LNG stream is sub-cooled with a refrigerating fluid in a first heat exchanger. This refrigerating fluid undergoes a closed second refrigeration cycle which is independent of the first cycle. The closed cycle comprises a phase of heating the refrigerating fluid in a second heat exchanger, and a phase of compressing the refrigerating fluid in a compression apparatus to a pressure greater than its critical pressure. It further comprises a phase of cooling the refrigerating fluid originating from the compression apparatus in the second heat exchanger and a phase of dynamically expanding of a proportion of the refrigerating fluid issuing from the second heat exchanger in a turbine. The refrigerating fluid is formed by a mixture of nitrogen-containing fluids.

Abstract: An LNG facility employing an enhanced fuel gas control system. The enhanced fuel gas control system is operable to produce fuel gas having a substantially constant Modified Wobbe Index (MWI) during start-up and steady-state operation of the LNG facility by processing one or more intermediate process streams in a fuel gas separator. In one embodiment, the fuel gas separator employs a hydrocarbon-separating membrane, which can remove heavy hydrocarbons and/or concentrate nitrogen from the incoming process streams.