A fluid transfer apparatus transfers fluid from a first bulk storage vessel at a gas pressure equal to or greater than a first gas pressure. The fluid transfers to a first or second supply vessel; each having a gas pressure equal to or less than a second pressure. The second pressure less than the first pressure. The fluid transfer continues until the fluid in the first or second supply vessel reaches a predetermined weight inside the first or second supply vessel. The fluid in the filled first or second supply vessel, at the predetermined weight, under a pressure equal to or less than the second pressure; and the fluid in a liquefied and gas state. The apparatus heats the fluid in the first or second supply vessel, filled to the predetermined weight, to bring the fluid in the first or second supply vessel to a third gas pressure. The third gas pressure higher than the first gas pressure and the second gas pressure. The fluid in the first or second supply vessel having the third gas pressure can include fluid in the liquefied gas state and gas state or super critical state.

A body structure has an inlet port that receives fluid, a first outlet port that connects to a top-fill line of a cryogenic tank, a second outlet port that connects to a bottom-fill line of a cryogenic tank and a slider tube cylinder. A cylinder housing connects to the body structure and has a pressure comparison cylinder with upper and lower volumes, with the latter in fluid communication with a cryogenic tank. A piston having a piston shaft slides within the pressure comparison cylinder. A pressure regulator is in fluid communication with the upper volume and the slider tube cylinder. A slider tube is connected to the piston shaft and slides within the slider tube cylinder. The slider tube cylinder selectively directs fluid to a top-fill line through the first outlet port or to a bottom-fill line through the second outlet port.

An apparatus for reliquefaction of boil-off gas for a vessel, comprises: a compression unit for compressing the boil-off gas discharged from the storage tank; and a heat exchanger for heat-exchanging the compressed boil-off gas compressed by the compression unit with the boil-off gas discharged from the storage tank; a first expansion means for dividing the boil-off gas passing through the heat exchanger into at least two flows including a first flow and a second flow, and expanding the divided first flow; a first intercooler for cooling the second flow remaining after the division of the first flow by using the first flow expanded by the expansion means as a refrigerant; and a receiver for receiving a second flow having passed through the first intercooler, in which a downstream pressure of the compression unit is controlled by a flow discharged from the receiver.

An apparatus for reliquefaction of boil-off gas for a vessel, comprises: a compression unit for compressing the boil-off gas discharged from the storage tank; and a heat exchanger for heat-exchanging the compressed boil-off gas compressed by the compression unit with the boil-off gas discharged from the storage tank; a first expansion means for dividing the boil-off gas passing through the heat exchanger into at least two flows including a first flow and a second flow, and expanding the divided first flow; a first intercooler for cooling the second flow remaining after the division of the first flow by using the first flow expanded by the expansion means as a refrigerant; and a receiver for receiving a second flow having passed through the first intercooler, in which a downstream pressure of the compression unit is controlled by a flow discharged from the receiver.

The alkylamine composition of the present disclosure contains: an alkylamine represented by the following formula (1) in an amount of 99.5% by volume or more; and water in an amount of 10 ppm by mass or more and 100 ppm by mass or less:

##STR00001##

wherein N is a nitrogen atom; R.sup.1 is a C1-C10 hydrocarbon group optionally having a ring, a heteroatom, or a halogen atom; R.sup.2 and R.sup.3 are each independently a hydrogen atom or a C1-C10 hydrocarbon group optionally having a ring, a heteroatom, or a halogen atom; provided that the hydrocarbon group, when it has a carbon number of 3 or more, may have a branched chain structure or a ring structure and that the heteroatom in the hydrocarbon group is a nitrogen atom, an oxygen atom, a sulfur atom, or a phosphorus atom; further, R.sup.1 and R.sup.2, when both of them are hydrocarbon groups having a carbon number of 1 or more, may be directly bonded to each other to form a ring structure; further, R.sup.1 or R.sup.2, which is directly bonded by a double bond to form a ring structure, may form an aromatic ring in the absence of R.sup.3; R.sup.1, R.sup.2, and R.sup.3 may be hydrocarbon groups which are the same as or different from one another; and R.sup.1 has at least one hydrogen atom at α carbon bonded to the nitrogen atom.

The alkylamine composition of the present disclosure contains: an alkylamine represented by the following formula (1) in an amount of 99.5% by volume or more; and water in an amount of 10 ppm by mass or more and 100 ppm by mass or less:

##STR00001##

wherein N is a nitrogen atom; R.sup.1 is a C1-C10 hydrocarbon group optionally having a ring, a heteroatom, or a halogen atom; R.sup.2 and R.sup.3 are each independently a hydrogen atom or a C1-C10 hydrocarbon group optionally having a ring, a heteroatom, or a halogen atom; provided that the hydrocarbon group, when it has a carbon number of 3 or more, may have a branched chain structure or a ring structure and that the heteroatom in the hydrocarbon group is a nitrogen atom, an oxygen atom, a sulfur atom, or a phosphorus atom; further, R.sup.1 and R.sup.2, when both of them are hydrocarbon groups having a carbon number of 1 or more, may be directly bonded to each other to form a ring structure; further, R.sup.1 or R.sup.2, which is directly bonded by a double bond to form a ring structure, may form an aromatic ring in the absence of R.sup.3; R.sup.1, R.sup.2, and R.sup.3 may be hydrocarbon groups which are the same as or different from one another; and R.sup.1 has at least one hydrogen atom at α carbon bonded to the nitrogen atom.

Disclosed herein are a diagnostic method using laser induced breakdown spectrum analysis and a diagnostic device for performing the same. The diagnostic device may include a laser projection module projecting a pulsed laser to a specimen, a light receiving module receiving a light generated by a plasma ablation induced at the specimen by the pulsed laser, a spectral member receiving and dividing the light generated by the plasma ablation; a sensor array including a plurality of sensors arranged to receive the divided light for each wavelength, and a controller obtaining spectrum data of the light generated by the plasma ablation from a specific exposure period, and determining whether or not the specimen is diseased based on the spectrum data of the light generated by the plasma ablation.

Disclosed herein are a diagnostic method using laser induced breakdown spectrum analysis and a diagnostic device for performing the same. The diagnostic device may include a laser projection module projecting a pulsed laser to a specimen, a light receiving module receiving a light generated by a plasma ablation induced at the specimen by the pulsed laser, a spectral member receiving and dividing the light generated by the plasma ablation; a sensor array including a plurality of sensors arranged to receive the divided light for each wavelength, and a controller obtaining spectrum data of the light generated by the plasma ablation from a specific exposure period, and determining whether or not the specimen is diseased based on the spectrum data of the light generated by the plasma ablation.

Disclosed herein is a BOG reliquefaction method for LNG ships. The BOG reliquefaction method for LNG ships includes: 1) compressing BOG; 2) cooling the BOG compressed in Step 1) through heat exchange between the compressed BOG and a refrigerant using a heat exchanger; 3) expanding the BOG cooled in Step 2); and 4) stably maintaining reliquefaction performance regardless of change in flow rate of the BOG compressed in Step 1) and supplied to the heat exchanger to be used as a reliquefaction target.

A BOG reliquefaction system includes: a compressor; a heat exchanger cooling the BOG compressed by the compressor through heat exchange using BOG not compressed by the compressor; a pressure reducer disposed downstream of the heat exchanger and reducing a pressure of fluid cooled by the heat exchanger; and a combination of a first temperature sensor disposed upstream of a cold fluid channel of the heat exchanger and a fourth temperature sensor disposed downstream of a hot fluid channel of the heat exchanger, combination of a second temperature sensor disposed downstream of the cold fluid channel of the heat exchanger and a third temperature sensor disposed upstream of the hot fluid channel of the heat exchanger, or combination of a first pressure sensor disposed upstream of the hot fluid channel of the heat exchanger and a second pressure sensor disposed downstream of the hot fluid channel of the heat exchanger.