F25J1/0218

Natural gas liquefying apparatus

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.

METHOD FOR OPTIMISING LIQUEFACTION OF NATURAL GAS
20180356150 · 2018-12-13 ·

A method for liquefying a hydrocarbon stream such as natural gas starting from a feed stream.

Method and System for Efficient Nonsynchronous LNG Production using Large Scale Multi-Shaft Gas Turbines

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.

HYDROGEN-NEON MIXTURE REFRIGERATION CYCLE FOR LARGE-SCALE HYDROGEN COOLING AND LIQUEFACTION

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.

LNG PLANT INCLUDING AN AXIAL COMPRESSOR AND A CENTRIFUGAL COMPRESSOR
20180209427 · 2018-07-26 ·

The LNG plant comprises a compression train and a further compression. The compression train (100) comprises comprising an engine and a compressor driven by the engine; the compressor is an axial compressor and comprises a first set of axial compression stages and a second set of axial compression stages arranged downstream the first set of axial compression stages; at least the first set and the second set of axial compression stages are housed inside one case. The further compression train comprises a further engine and a further compressor driven by the further engine; the further compressor is a centrifugal compressor and comprises a first set of impellers and a second set of impellers arranged downstream or upstream the first set of impellers.

Liquefaction of Natural Gas
20180172344 · 2018-06-21 ·

Systems and a method for the formation of a liquefied natural gas (LNG) are disclosed herein. The system includes a first fluorocarbon refrigeration system configured to chill a natural gas using a first fluorocarbon refrigerant and a second fluorocarbon refrigeration system configured to further chill the natural gas using a second fluorocarbon refrigerant. The system also includes a nitrogen refrigeration system configured to cool the natural gas using a nitrogen refrigerant to produce LNG and a nitrogen rejection unit configured to remove nitrogen from the LNG. As an alternative embodiment, the nitrogen refrigeration system can be replaced by a methane autorefrigeration system.

Mixed refrigerant hydrogen liquefaction device and method of using same

The present disclosure designs a mixed refrigerant hydrogen liquefaction device including a normal-pressure precooling cold box, a vacuum cryogenic cold box, a hydrogen refrigeration cycle compressor unit, a nitrogen cycle refrigeration unit and a mixed refrigerant cycle refrigeration unit. The precooling section uses a mixed refrigerant process and a nitrogen cycle refrigeration process as the main sources of cold energy. The refrigerant refrigeration cycle is the main source of cold energy in the temperature range of 303K to 113K. The liquid nitrogen refrigeration cycle is the main source of cold energy in the temperature range of 130K to 80K. The hydrogen refrigeration cycle provides cold energy for the temperature range of 80K to 20K. Most of the BOG generated in a storage part is recovered by an ejector. A plate-fin heat exchanger is filled with ortho-para hydrogen conversion catalysts to realize the para hydrogen content of liquefied hydrogen 98%.

SYSTEM AND METHOD FOR LIQUEFACTION OF NATURAL GAS
20170160008 · 2017-06-08 ·

By using the power generated by an expander by an expansion of material gas, the outlet pressure of a compressor is increased, and a requirement on the cooling capacity of a cooler is reduced. The liquefaction system (1) for natural gas comprises a first expander (3) for generating power by using natural gas under pressure as material gas; a first cooling unit (11, 12) for cooling the material gas depressurized by expansion in the first expander; a distillation unit (15) for reducing or eliminating a heavy component in the material gas by distilling the material gas cooled by the first cooling unit; a first compressor (4) for compressing the material gas from which the heavy component was reduced or eliminated by the distillation unit by using power generated in the first expander; and a liquefaction unit (21) for liquefying the material gas compressed by the first compressor by exchanging heat with a refrigerant.

Semi-closed loop LNG process
09651300 · 2017-05-16 · ·

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.

Integrated Pre-Cooled Mixed Refrigerant System and Method

A system and method for cooling and liquefying a gas in a heat exchanger that includes compressing and cooling a mixed refrigerant using first and last compression and cooling cycles so that high pressure liquid and vapor streams are formed. The high pressure liquid and vapor streams are cooled in the heat exchanger and then expanded so that a primary refrigeration stream is provided in the heat exchanger. The mixed refrigerant is cooled and equilibrated between the first and last compression and cooling cycles so that a pre-cool liquid stream is formed and subcooled in the heat exchanger. The stream is then expanded and passed through the heat exchanger as a pre-cool refrigeration stream. A stream of gas is passed through the heat exchanger in countercurrent heat exchange with the primary refrigeration stream and the pre-cool refrigeration stream so that the gas is cooled. A resulting vapor stream from the primary refrigeration stream passage and a two-phase stream from the pre-cool refrigeration stream passage exit the warm end of the exchanger and are combined and undergo a simultaneous heat and mass transfer operation prior to the first compression and cooling cycle so that a reduced temperature vapor stream is provided to the first stage compressor so as to lower power consumption by the system. Additionally, the warm end of the cooling curve is nearly closed further reducing power consumption. Heavy components of the refrigerant are also kept out of the cold end of the process, reducing the possibility of refrigerant freezing, as well as facilitating a refrigerant management scheme.