A drive system for liquefied natural gas (LNG) refrigeration compressors in a LNG liquefaction plant. Each of three refrigeration compression strings include refrigeration compressors and a multi-shaft gas turbine capable of non-synchronous operation. The multi-shaft gas turbine is operationally connected to the refrigeration compressors and is configured to drive the one or more refrigeration compressors. The multi-shaft gas turbine uses its inherent speed turndown range to start the one or more refrigeration compressors from rest, bring the one or more refrigeration compressors up to an operating rotational speed, and adjust compressor operating points to maximize efficiency of the one or more refrigeration compressors, without assistance from electrical motors with drive-through capability and variable frequency drives.

The invention relates to a refrigeration system that in mode 1 prepares a reservoir of cooled refrigerant before flowing unconditioned gas through the system, and in mode 2, continuously cools feed gas with the prepared refrigerant inventory, extracting natural gas liquids (NGLs) comprising predominantly ethane, propane, butane, and condensate and controlled by a control system without needing ramp up time.

Implementations described and claimed herein provide systems and methods for processing liquefied natural gas (LNG). In one implementation, a solvent is injected into a feed of natural gas at a solvent injection point. A mixed feed is produced from a dispersal of the solvent into the feed of natural gas. The mixed feed contains heavy components. A chilled feed is produced by chilling the mixed feed. The chilled feed includes a vapor and a condensed liquid. The condensed liquid contains a fouling portion of the heavy components condensed by the solvent during chilling. The liquid containing the fouling portion of the heavy components is separated from the vapor. The vapor is directed into a feed chiller heat exchanger following separation of the liquid containing the fouling portion of the heavy components from the vapor, such that the vapor being directed into feed chiller heat exchanger is free of freezing components.

A method for improving the efficiency of liquefied natural gas (LNG) liquefaction including receiving a gas feed stream at an LNG facility, condensing the gas feed stream into an LNG product stream, removing nitrogen from the LNG product stream via a nitrogen rejection unit coupled with the LNG facility to produce a final LNG product stream, analyzing one or more process samples taken throughout the liquefaction and nitrogen removal processes via mass spectrometry, and adjusting one or more aspects of the LNG processing system based on the analysis.

A system and method for producing liquefied natural gas (LNG) from a natural gas stream. Each of a plurality of LNG trains liquefies a portion of the natural gas stream to generate a warm LNG stream in a first operating mode, and a cold LNG stream in a second operating mode. A sub-cooling unit is configured to, in the first operating mode, sub-cool the warm LNG streams to thereby generate a combined cold LNG stream. The warm LNG streams have a higher temperature than a temperature of the cold LNG streams in the second operating mode and the combined cold LNG stream. The combined cold LNG stream has, in the first operating mode, a higher flow rate than the flow rate of the cold LNG streams in the second operating mode.

A core-in-shell heat exchanger, a method of fabricating the core-in-shell heat exchanger, and a method of exchanging heat in a core-in-shell heat exchanger disposed on a slosh-inducing moving platform are described. The method of exchanging heat includes introducing a shell-side fluid into a shell of the core-in-shell heat exchanger and introducing a fluid to be cooled into each of one or more cores of the core-in-shell heat exchanger, the one or more cores being arranged along an axial length of the shell with a plurality of baffles disposed on either side of the one or more cores along the axial length of the shell to reduce slosh of the shell-side fluid. The method also includes draining excess shell-side fluid using a plurality of drains, at least two of the plurality of drains being disposed on opposite sides of one of the plurality of baffles.

A quench system for a refrigeration cycle of a liquefied natural gas (LNG) facility includes at least one compressor for compressing a refrigerant that cools a natural gas stream. Also included is a quench fluid supply structure containing a quench fluid. Further included is a cooler vessel and a quench fluid line extending from the quench fluid supply structure and through the cooler vessel for cooling therein, the quench fluid maintained in a liquid state through the entirety of the quench fluid line. Yet further included is a quench control valve disposed downstream of the cooler vessel to control a flow rate of the quench fluid routed therein. Also included is a refrigerant suction drum located downstream of the quench control valve and configured to receive the quench fluid from the quench fluid line, the refrigerant suction drum in fluid communication with at least one component for cooling.

A drive system for liquefied natural gas (LNG) refrigeration compressors in a LNG liquefaction plant. Each of three refrigeration compression strings include refrigeration compressors and a multi-shaft gas turbine capable of non-synchronous operation. The multi-shaft gas turbine is operationally connected to the refrigeration compressors and is configured to drive the one or more refrigeration compressors. The multi-shaft gas turbine uses its inherent speed turndown range to start the one or more refrigeration compressors from rest, bring the one or more refrigeration compressors up to an operating rotational speed, and adjust compressor operating points to maximize efficiency of the one or more refrigeration compressors, without assistance from electrical motors with drive-through capability and variable frequency drives.

A method of constructing a plate fin heat exchanger includes joining a first side bar formed from a nickel-iron alloy to a first end of a fin element formed from a nickel-iron alloy through a first nickel-iron alloy bond, and joining a second side bar formed from a nickel-iron alloy to a second end of the fin element through a second nickel-iron alloy bond to create a first layer of the plate fin heat exchanger. The fin element defines a fluid passage.

A natural gas liquefying apparatus is provided. At least a part of a cooling region, in which a precooling unit and a liquefaction unit are arranged, and at least a part of a compression region, in which first and second compressors compressing refrigerants to be used in the precooling unit and the liquefaction unit are arranged, are arranged to be opposed to each other across a long side of a second refrigerant cooler group arrangement region in which a liquefying refrigerant is cooled. A first refrigerant cooler group arrangement region, in which a precooling refrigerant is cooled, is arranged so that a long side of the first refrigerant cooler group arrangement region is opposed to one side of a rectangular region including the compression region, the one side being different from a side of the rectangular region opposed to a long side of the second refrigerant cooler group arrangement region.