The disclosure describes processes which include cooling a natural gas product stream to a cryogenic liquid storage temperature by way of refrigeration streams which include a primary refrigeration stream, a secondary refrigeration stream, and a tertiary refrigeration stream in a refrigeration system. After leaving the refrigeration system, the pressure of each refrigeration stream is increased, and upon reaching a sufficient pressure, the refrigeration streams are recycled to flow back into the refrigeration system as a recycle stream. The disclosure further describes systems capable of performing the processes. The processes and systems can include one or more sensors and one or more controls capable of adjusting a flow rate, flow volume, and/or flow ratio among one or more gas streams to maximize cooling efficiency based on monitoring from the one or more sensors. Mobile natural gas liquefaction systems are also described.

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 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 generated by each of the plurality of LNG trains to thereby generate a plurality of cold LNG streams. The warm LNG streams have a higher temperature than a temperature of the cold LNG streams in the second operating mode and the plurality of cold LNG streams. The combined flow rate of the plurality of cold LNG streams has, in the first operating mode, a higher flow rate than the combined flow rate of the cold LNG streams in the second operating mode.

An LNG refrigerant compressor train (1) is disclosed. The train comprises: a driver section (11), drivingly coupled to a compressor section (13) through a shaft line (1). The compressor section is comprised of at least one refrigerant fluid compressor, driven into rotation by the driver section (11).

The present invention relates to a refrigerant composition comprising neon and hydrogen. The present invention further relates to the use of the refrigerant composition in liquefying gaseous substances such as hydrogen or helium.

A system and method for increasing the efficiency of natural gas liquefaction processes by using a hybrid cooling system and method. More specifically, a system and method for converting a transcritical precooling refrigeration process to a subcritical process. In one embodiment, the refrigerant is cooled to sub-critical temperature using an economizer. In another embodiment, the refrigerant is cooled to a sub-critical temperature using an auxiliary heat exchanger. Optionally, the economizer or auxiliary heat exchanger can be bypassed when ambient temperatures are sufficiently low to cool the refrigerant to a sub-critical temperature. In another embodiment, the refrigerant is isentropically expanded.

A method for operating a main cryogenic heat exchanger for use in a natural gas liquefaction process, involves monitoring or predicting variations in the flow rate of a feed gas stream provided to the main cryogenic heat exchanger. When a variation of the flow rate exceeding a predetermined threshold value is monitored or predicted, a control scheme is started to control one or more compressor recycle valves in response to the monitored or predicted variation of the flow rate to recycle part of a compressed mixed refrigerant stream in a refrigerant loop.

The device (600) for liquefying a natural gas comprises: a first centrifugal compressor (605), a fractionating means (110), a second centrifugal compressor (610), a first heat exchange body (115), a second heat exchange body (120) and a return conduit (125) leading to the first compressor, upstream of an inlet (116) in the first exchange body, a third heat exchange body (420), a third centrifugal compressor (620), the first and third centrifugal compressors being actuated by a single common turbine (630), a casing (635) common to the first compressor and the third compressor, a cooling means (430) and a transfer conduit (435) leading to the third exchange body.

A natural gas liquefying apparatus includes: a precooling unit, which is a treatment unit configured to precool natural gas; a liquefying unit, which is a treatment unit configured to liquefy the natural gas; a refrigerant cooling unit, which is a treatment unit configured to cool a liquefying refrigerant; a compression unit configured to compress vaporized refrigerants; and a pipe rack including air-cooled coolers arrayed and arranged on an upper surface. The treatment units and the compression unit are separately arranged in a first arrangement region and a second arrangement region arranged opposed to each other across a long side of the pipe rack. The pipe rack interposed between the first and second arrangement regions has a region in which no air-cooled cooler is arranged in order to arrange a plurality of pipes, through which refrigerants are allowed to flow, in a direction of a short side of the pipe rack.

The disclosure describes processes which include cooling a natural gas product stream to a cryogenic liquid storage temperature by way of refrigeration streams which include a primary refrigeration stream, a secondary refrigeration stream, and a tertiary refrigeration stream in a refrigeration system. After leaving the refrigeration system, the pressure of each refrigeration stream is increased, and upon reaching a sufficient pressure, the refrigeration streams are recycled to flow back into the refrigeration system as a recycle stream. The disclosure further describes systems capable of performing the processes. The processes and systems can include one or more sensors and one or more controls capable of adjusting a flow rate, flow volume, and/or flow ratio among one or more gas streams to maximize cooling efficiency based on monitoring from the one or more sensors. Mobile natural gas liquefaction systems are also described.