The present disclosure relates to a natural gas hydrate tank container loading system for transporting natural gas hydrate, and the present disclosure provides a natural gas hydrate tank container loading system, enabling self-powered power generation and boil-off (BOG) gas treatment, includes: a refrigerator for inhibiting the generation of boil-off gas which naturally generates in a natural gas hydrate tank container during transportation; and a solar cell, a battery, and a generator, which operates by means of the boil-off gas, for supplying electric power to the refrigerator, thereby ensuring a generation capacity sufficient to operate the refrigerator by means of the solar cell, the generator, and the battery, and thus always maintaining a stable phase equilibrium (self-preservation) in the natural gas hydrate tank container even during long-distance transportation and solving problems of fire, environmental pollution, or the like which occur when the boil-off gas (BOG) is discharged to the outside.

A tank state estimating method of estimating a state in a tank at a predetermined point in time on a sailing course of an LNG carrier is provided. The LNG carrier carrying LNG stored in the tank as a cargo. The tank state estimating method includes: a first step of acquiring information related to specification of the tank; a second step of acquiring information related to a state in the tank at a start point of a target section on the course; a third step of acquiring information on a predictive value of liquid fluctuation of the LNG in the tank during the section, the predictive value being obtained on a basis of a weather forecasting value during the section and information on the weather forecasting value; and a fourth step of calculating the state in the tank at an end point of the section by thermal transfer calculation based on thermodynamics on a basis of the information acquired in the first to third steps in assuming that a heat input to the tank during the section is used for vaporization of the LNG in the tank.

The present invention relates to a gas treatment system and a ship including the same. The gas treatment system treats liquefied gas as heavier hydrocarbons or ammonia. The gas treatment system includes: a fuel tank storing liquefied gas as a fuel to be supplied to a propulsion engine of a ship; a liquefied gas supply line supplying the liquefied gas of the fuel tank in a liquid phase to the propulsion engine, the liquefied gas supply line having a high pressure pump provided thereon; a reliquefaction apparatus liquefying boil-off gas generated in a cargo tank storing liquefied gas; and a liquefied gas collection line collecting the liquid liquefied gas discharged from the propulsion engine upstream of the high pressure pump. The reliquefaction apparatus transfers the liquefied boil-off gas to the fuel tank, thereby allowing the liquefied boil-off gas to be supplied to the propulsion engine by the high pressure pump.

A system for reliquefying a boil off gas generated in a storage tank includes a first compressor compressing a partial amount (hereinafter, referred to as ‘fluid a’) of boil off gas discharged from the storage tank, a second compressor compressing another partial amount (hereinafter, referred to as ‘fluid b’) of boil off gas discharged from the storage tank, a second expanding unit expanding a partial amount (hereinafter, referred to as ‘fluid c’) of a flow formed as the fluid a and the fluid b join, a heat-exchanger cooling another partial amount (hereinafter, referred to as ‘fluid d’) of the flow formed as the fluid a and the fluid b join, and a first expanding unit expanding the fluid d cooled by the heat-exchanger, wherein the heat-exchanger heat-exchanges the fluid d with the fluid c as a coolant expanded by the second expanding unit to cool the fluid d.

Provided is a liquefied gas transfer device for reducing boil-off gas. The liquefied gas transfer device for reducing boil-off gas comprises: at least one transfer pipe formed in a vertical direction inside a quay for storing liquefied gas so as to transfer the liquefied gas; a branch pipe which is branched from a lower part of the transfer pipe to one side of the transfer pipe, and which has an end part opened toward a bottom surface of the quay; a valve which is connected to the branch pipe and/or the transfer pipe, and which opens and closes the branch pipe or the transfer pipe so as to move the liquefied gas from the transfer pipe to the branch pipe; and a resistance member disposed inside the branch pipe so as to interrupt the flow of the liquefied gas.

A floating type LNG station floats on the sea and is used for refueling a ship or a marine structure using LNG. The floating LNG station comprises: a floating structure; an LNG tank which is prepared for storing LNG in the floating structure; an LNG line for discharging the LNG from the LNG tank to the ship or the marine structure; and an LNG pump which provides the LNG line with pumping force for discharging the LNG.

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.

Disclosed herein is a micro-leak detection system of a reliquefaction system for ships. The micro-leak detection system includes: a reliquefaction system reliquefying boil-off gas generated from a liquefied gas stored in a storage tank in a ship by recovering cold heat from the boil-off gas in a heat exchanger, compressing the boil-off gas, and cooling the compressed boil-gas in the heat exchanger through heat exchange with refrigerant circulated along a refrigerant circulation line; a heater heating the boil-off gas to be supplied from the storage tank to the heat exchanger through heat exchange with an antifreeze liquid; and a micro-leak detection device connected to a drain port through which a remaining liquid is drained from the heater and detecting small leaks in the heater.

A gas processing system according to an embodiment of the present invention controls inflow fuel pressure of a low pressure demand source according to an operation or a non-operation of a high pressure demand source and the low pressure demand source.

The invention relates to a gas treatment method and system of a gas storage facility (2), in particular on board a ship, the method comprising the following stages: an extraction of a first gas (4a, 4b, 5a, 5b,) in the liquid state from a first tank (4) or first vessel (5; 500), a first subcooling of the first gas in the liquid state, and storage of the subcooled first gas in the liquid state in the lower part of the first tank (4) or of the first vessel (5; 500) or of a second tank or of a second vessel, so as to constitute a reserve layer of cold (4c, 5c, 500c) of the subcooled first gas in the liquid state at the bottom of the first or second tank (4) or of the first or second vessel (5; 500).