JP2023508857A - Liquefied gas supply system and method for ships, and liquefied gas fuel supply system for ships - Google Patents

Abstract

Kind Code: A1 A liquefied gas supply system and method for a ship, and a liquefied gas in the fuel tank of the ship, in which evaporative gas generated when the liquefied gas is supplied to the liquefied gas tank of the ship is treated within the ship without being returned to the outside. To provide a liquefied gas fuel supply system for a ship, capable of treating the evaporative gas generated when supplying the gas fuel inside the ship without returning it to the outside. SOLUTION: In a liquefied gas supply system in a ship that supplies liquefied gas from a ship that supplies liquefied gas to a ship equipped with a plurality of liquefied gas tanks, any one of the plurality of liquefied gas tanks is supplied from the ship that supplies liquefied gas. A liquefied gas line that supplies liquefied gas to one liquefied gas tank, a gas discharge line that discharges evaporative gas generated when supplying liquefied gas to any one liquefied gas tank, and one or more other liquefaction of evaporative gas and a gas supply line that supplies the gas tank. [Selection drawing] Fig. 1

Description

TECHNICAL FIELD The present invention relates to a liquefied gas supply system and method for a ship, in which evaporative gas generated when liquefied gas is supplied to a liquefied gas storage tank of the ship is treated onboard without returning to the outside.

In addition, the present invention relates to a liquefied gas fuel supply system for a ship, in which the evaporative gas generated when the liquefied gas fuel is supplied to the liquefied gas fuel tank of the ship is treated within the ship without being returned to the outside. .

In general, natural gas is produced in a liquefied natural gas (LNG) state at a production site, and then transported to an onshore gas terminal by an LNG carrier.

Liquefied gas tanks, such as empty liquefied gas storage tanks on ships, are generally filled with an inert gas to prevent gas explosions. Therefore, before operating the LNG carrier or before storing LNG in the LNG storage tank of the LNG carrier, a replacement process (gassing up) is carried out to replace the inert gas in the LNG storage tank with natural gas. do.

After the replacement step, a cooling down step is performed to lower the internal temperature of the LNG storage tank before supplying LNG to the LNG storage tank.

On the other hand, since a large amount of evaporative gas (BOG, boil-off gas) is generated during the cool-down process and the supply of LNG, the internal pressure of the LNG storage tank is maintained by conveying the evaporative gas to the gas terminal.

As an example, about 4 to 7 MT/hr of evaporative gas is generated in the cool down process, and about 7 to 9 MT/hr of evaporative gas is generated in the LNG supply process. In this way, at the gas terminal, when supplying LNG to the LNG storage tank, about 4 to 9 MT/hr of evaporative gas is returned from the ship in each of the above processes, and the returned evaporative gas is reliquefied and recovered. or combusted in a GCU (Gas Combustion Unit).

On the other hand, as a measure for solving the problem of environmental pollution, LNG bunkering vessels are becoming more active as LNG fueled vessels using LNG as fuel become popular. An LNG bunkering vessel is a vessel that goes to where the LNG fueled vessel is anchored and supplies LNG from the LNG bunkering vessel to the LNG fueled vessel at sea.

Also when supplying LNG from an LNG bunkering ship to an LNG fueled ship, a large amount of evaporative gas is generated in the LNG fueled ship.

Since LNG-fueled ships carry cargo, it is not easy to install piping to collect evaporative emissions. It is preferable that the evaporative gas generated during the supply of is recovered from the LNG fueled ship and processed by the LNG bunkering ship.

An empty LNG fuel tank before LNG is supplied is filled with an inert gas to prevent gas explosion, as described above. That is, during the commissioning stage before the LNG-fueled ship begins operation or during operation, the empty LNG fuel tanks must be filled with natural gas to replace the inert gas in the LNG fuel tanks before storing the LNG. A replacement step is required.

Also, after the replacement process, it is necessary to supply LNG to the LNG fuel tank after performing a cooling down process to lower the internal temperature of the LNG fuel tank.

On the other hand, since a large amount of evaporative gas (BOG) is generated during the cool-down process and the supply of LNG, the internal pressure of the LNG fuel tank can be maintained by returning the evaporative gas to the gas terminal.

Therefore, LNG bunkering ships can be used to supply LNG to LNG fueled ships on the sea. Lively discussions are being held on technologies for supplying LNG for trial operation to carriers and the like.

As mentioned above, in order to supply empty LNG storage tanks on an LNG carrier to be commissioned with LNG, it is necessary to carry out a replacement step and a cool down step beforehand. In other words, when supplying LNG for trial operation to an LNG carrier using an LNG bunkering ship, about 4 to 9 MT/hr of evaporative gas recovered from each process from the LNG carrier is directly processed by the LNG bunkering ship. Must.

However, LNG bunkering vessel GCUs have limited evaporative gas processing capacity. In fact, the GCU between the LNG bunkering vessel that is being built in South Korea with the LNG bunkering function and the LNG bunkering vessel that is actually built by a Korean shipbuilding company and is operating in European ports The evaporative gas processing capacity is only less than 1 ton.

In addition, since the GCU and reliquefaction equipment that can process the evaporative gas are not ready for operation on the LNG carrier in the trial operation stage, it is impossible to process the evaporative gas on the LNG carrier itself. .

Therefore, the reality is that the entire amount of evaporative gas generated during the cool-down process and the supply of LNG cannot be treated unless the evaporative gas is discharged into the atmosphere.

Therefore, an object of the present invention is to solve the above-described problems, for example, without recovering the evaporative gas generated when supplying LNG or LNG for trial operation to the storage tank of the LNG carrier to the LNG bunkering ship. , a system and method for supplying liquefied gas on board a ship, which can be processed on the LNG carrier itself.

In addition, for example, the evaporative gas generated when LNG is supplied to the LNG fuel tank of the LNG fueled ship can be processed by the LNG fueled ship itself without being collected by the LNG bunkering ship. Provide supply system.

To achieve the above object, one embodiment of the present invention provides a liquefied gas supply system for a ship that supplies liquefied gas from a liquefied gas supply ship to a ship equipped with a plurality of liquefied gas storage tanks, A liquefied gas line that supplies liquefied gas from a ship to any one of the plurality of liquefied gas storage tanks, and a liquefied gas produced by supplying liquefied gas to any one of the liquefied gas storage tanks. A system for supplying liquefied gas on a ship, comprising a gas discharge line for discharging evaporative gas from the evaporative gas, and a gas supply line for supplying said evaporative gas to one or more other liquefied gas storage tanks.

Preferably, the heater further comprises a heater for heating the evaporative gas discharged along the gas discharge line, and the evaporative gas heated by the heater is supplied to one or more other liquefied gas storage via the gas supply line. supplied to the tank.

Preferably, evaporative gas generated when supplying the liquefied gas to any one of the liquefied gas storage tanks is supplied to another liquefied gas storage tank.

Preferably, evaporative gas generated when supplying liquefied gas to any one of said liquefied gas storage tanks is supplied to all other liquefied gas storage tanks.

Preferably, the liquefied gas line connects the liquefied gas supply vessel and the liquefied gas storage tank, supplies the liquefied gas through a liquid crossover line to which the liquefied gas is transferred from the liquefied gas supply vessel, and the liquid crossover line. A liquid line is provided for branching and supplying the liquefied gas to each liquefied gas storage tank.

Preferably, the liquid line is configured to isolate the liquid line so that when liquefied gas is supplied through the liquid crossover line, the liquefied gas is not supplied to one or more other liquefied gas storage tanks. Further comprising one or more isolation valves.

Preferably, said isolation valve is installed between the point at which said liquid crossover line joins said liquid line and the point at which it branches to the first connecting liquefied gas storage tank.

In order to achieve the above object, another embodiment of the present invention provides a method for supplying liquefied gas in a ship that supplies liquefied gas from a liquefied gas supply ship to a ship equipped with a plurality of liquefied gas storage tanks, comprising: A liquefied gas supply step of supplying liquefied gas from a supply vessel to any one of the plurality of liquefied gas storage tanks, and supplying liquefied gas to any one of the liquefied gas storage tanks an evaporative gas discharging step of discharging the generated evaporative gas; and a replacement gas supply step of supplying up to liquefied gas.

Preferably, the evaporative gas discharged in the evaporative gas discharge step is heated, and the heated evaporative gas is supplied to one or more other liquefied gas storage tanks.

Preferably, evaporative gas generated when the liquefied gas is supplied to any one of the liquefied gas storage tanks is supplied to another liquefied gas storage tank.

Preferably, evaporative gas generated when supplying liquefied gas to any one of the liquefied gas storage tanks is supplied to all other liquefied gas storage tanks.

Preferably, when the liquefied gas is supplied to any one of the liquefied gas storage tanks, the supply of the liquefied gas to one or more other liquefied gas storage tanks is cut off.

In order to achieve the above-mentioned objects, still another embodiment of the present invention provides a trial liquefaction in a vessel that supplies trial liquefied gas from a liquefied gas supply vessel to a liquefied gas carrier having a plurality of liquefied gas storage tanks. In the gas supply method, a cooling step is performed in the plurality of liquefied gas storage tanks using a stripping line provided for injecting the liquefied gas from the liquefied gas supply ship into the liquefied gas storage tanks. supplying a cool-down liquefied gas to a cool-down storage tank ready to be performed; and evaporative gas generated in said cool-down storage tank by supplying liquefied gas to said cool-down storage tank. through a gas line provided for discharging the gas from the liquefied gas storage tank; supplying a first replacement gas to a first replacement storage tank ready to perform a replacement step in the gas storage tank.

Preferably, the first replacement storage tank is filled with an inert gas, and the inert gas discharged from the first replacement storage tank by supplying the evaporative gas to the first replacement storage tank Using a liquid line provided for storing the gas in the liquefied gas storage tank or discharging the liquefied gas from the liquefied gas storage tank and a second connecting line connecting the liquid line and the vent mast, The method further comprises discharging the first inert gas supplied to the vent mast.

Preferably, the step of supplying the first replacement gas comprises an evaporative gas treatment step of compressing and heating the evaporative gas discharged from the cool-down storage tank before supplying it to the first replacement storage tank. .

Preferably, the amount of evaporative gas discharged from the cool-down storage tank is equal to or greater than the amount of evaporative gas required in the replacement step of the first replacement storage tank, and the cool-down storage tank is cooled. When the down is completed, the replacement process for the first replacement storage tank is completed.

Preferably, once the cool-down of said cool-down storage tank is complete, said cool-down storage tank is ready to store liquefied gas, and said liquefied gas is supplied to said supply storage tank ready to store liquefied gas. a liquefied gas supply step of supplying the liquefied gas using a liquid line provided for storing or discharging the liquefied gas in the liquefied gas storage tank, and supplying the liquefied gas to the supply storage tank an evaporative gas discharge step of discharging the evaporative gas generated in the supply storage tank by supplying the evaporative gas through the gas line; and supplying a second replacement gas to a second replacement storage tank ready to perform a tank replacement step.

Preferably, the second replacement storage tank is filled with an inert gas and the inert gas discharged from the second replacement storage tank by supplying the evaporative gas to the second replacement storage tank. A second inert gas discharging step of supplying gas to the vent mast using the liquid line and a second connect line connecting the liquid line and the vent mast is further included.

Preferably, said liquid line and said supply storage tank are connected by a first liquid line, said liquid line and said second replacement storage tank are connected by a third liquid line, and said liquid line is connected to said first liquid line. and the branch point of the third liquid line, and the isolation valve is closed during the step of discharging the second inert gas.

Preferably, the second replacement gas supply step comprises a second evaporative gas treatment step of compressing and heating the evaporative gas discharged from the supply storage tank before supplying it to the second replacement storage tank.

In order to achieve the above-mentioned objects, still another embodiment of the present invention provides a trial liquefaction in a vessel that supplies trial liquefied gas from a liquefied gas supply vessel to a liquefied gas carrier having a plurality of liquefied gas storage tanks. In a gas supply system, a cool provided for injecting said liquefied gas from said liquefied gas supply vessel into said liquefied gas storage tanks and arranged to perform a cool down step in said plurality of liquefied gas storage tanks. a stripping line through which cool-down liquefied gas is transferred to a down storage tank; and a stripping line for storing said liquefied gas in said liquefied gas storage tank or for discharging said liquefied gas from said liquefied gas storage tank, said cooling-down a liquid line through which the commissioning liquefied gas is transferred to a supply storage tank that is completed and ready to store the liquefied gas; Alternatively, a gas line for discharging evaporative gas generated in the cool-down storage tank or the supply storage tank by supplying liquefied gas to the supply storage tank, and the cooling-down gas line is provided through the gas line. Supply of liquefied gas for commissioning on a ship, wherein evaporative gas discharged from storage tanks and supply storage tanks is transferred to a replacement storage tank prepared to perform a replacement step among said plurality of liquefied gas storage tanks. provide the system.

Preferably, a second connect line that connects the liquid line and the vent mast is further provided, the replacement storage tank is filled with an inert gas, and the replacement storage tank is supplied with evaporative gas to supply the replacement storage tank with an inert gas. Inert gas discharged from the storage tank is transferred to the vent mast through the liquid line and the second connecting line.

Preferably, a supply liquid branch line connecting the liquid line and the cool-down storage tank or the supply storage tank, a replacement liquid branch line connecting the liquid line and the replacement storage tank, and from the liquid line It is installed between the point where the supply liquid branch line branches and the point where the replacement liquid branch line branches, and the liquefied gas transferred to the cool-down storage tank or the supply storage tank flows by opening and closing control. and an isolation valve for isolating from each other a liquid line path through which the inert gas discharged from the replacement storage tank flows.

To achieve the above object, one embodiment of the present invention provides a liquefied gas supply system for a ship that supplies liquefied gas from a liquefied gas supply ship to a ship equipped with a plurality of liquefied gas storage tanks, A liquefied gas line that supplies liquefied gas from a ship to any one of the plurality of liquefied gas storage tanks, and a liquefied gas produced by supplying liquefied gas to any one of the liquefied gas storage tanks. and a gas supply line for discharging the evaporative gas to the one or more other liquefied gas storage tanks, wherein the gas discharged from the liquefied gas storage tank to which the evaporative gas is supplied passes through the liquefied gas line. provided in a liquefied gas line between a liquefied gas storage tank to which the liquefied gas is supplied through the liquefied gas line and a liquefied gas storage tank to which the evaporative gas is supplied, and the liquefied gas Provided is a liquefied gas supply system for a ship, further comprising an isolation valve for blocking the liquefied gas flowing along the line and the evaporative gas flow from mixing.

Preferably, the apparatus further comprises a manifold and a crossover line connecting the manifold and the liquefied gas line, and the isolation valve may be a three-way valve installed at a point where the crossover line and the liquefied gas line are connected.

Preferably, the heater further comprises a heater for heating the evaporative gas discharged along the gas discharge line, and the evaporative gas heated by the heater is supplied to one or more other liquefied gas storage via the gas supply line. supplied to the tank.

Preferably, the gas discharged from the liquefied gas storage tank to which the evaporative gas is supplied is an inert gas, further comprising a connect line connecting the liquefied gas line and the vent mast, wherein the inert gas is the liquefied gas storage tank. Transferred from the tank to the vent mast.

In order to achieve the above object, another embodiment of the present invention provides a method for supplying liquefied gas in a ship that supplies liquefied gas from a liquefied gas supply ship to a ship equipped with a plurality of liquefied gas storage tanks, comprising: A liquefied gas supply step of supplying liquefied gas from a supply vessel to any one of the plurality of liquefied gas storage tanks, and supplying liquefied gas to any one of the liquefied gas storage tanks an evaporative gas discharge step of discharging the generated evaporative gas; and supplying the evaporative gas discharged from any one of the liquefied gas storage tanks to one or more other liquefied gas storage tanks of the plurality of liquefied gas storage tanks. and an inert gas discharging step of discharging the inert gas filled in the liquefied gas storage tank to which the evaporative gas is supplied by supplying the evaporative gas, Active gas provides a method of supplying liquefied gas in a ship, wherein said liquefied gas is discharged via a supply line to said liquefied gas storage tank.

Preferably, the inert gas discharge step comprises separating a portion through which the liquefied gas flows to the liquefied gas storage tank and a portion through which the inert gas flows in a line that supplies the liquefied gas to the liquefied gas storage tank. An isolation step is provided to isolate each other.

Preferably, the evaporative gas discharged in the evaporative gas discharging step is heated, and the heated evaporative gas is supplied to one or more other liquefied gas storage tanks.

In order to achieve the above-mentioned objects, still another embodiment of the present invention provides a liquefied gas for trial operation in a vessel that supplies liquefied gas for trial operation from a liquefied gas supply vessel to a liquefied gas carrier having a plurality of liquefied gas storage tanks. In the supply system, each of the plurality of liquefied gas storage tanks is provided with a liquid branch line for transferring liquefied gas, a stripping branch line for injecting liquefied gas, and a gas branch line for transferring evaporative gas, A gas line connecting gas branch lines and a liquid line connecting each of the liquid branch lines are provided, and the plurality of liquefied gas storage tanks are filled with an inert gas to perform a replacement step. and a storage tank ready to be supplied with liquefied gas upon completion of said replacement step, and connected to said storage tank ready to be supplied with said liquefied gas from said liquefied gas supply vessel. A liquefied gas is supplied using a liquid branch line or a stripping branch line, and evaporative gas discharged from a storage tank prepared to be supplied with the liquefied gas is passed through the gas line to the replacement storage. An isolation valve is further provided for controlling the path of the inert gas transferred to the tank and filling the replacement storage tank so that the inert gas is discharged through a liquid branch line provided in the replacement storage tank. provides a liquefied gas supply system for commissioning on ships.

Preferably, a liquid crossover line connecting the liquid line and the manifold of the liquefied gas carrier is further provided, and the isolation valve is a three-way valve installed at a point where the liquid line and the liquid crossover line are connected. obtain.

Preferably, the isolation valve is located at a point where the liquid branch line of the storage tank ready to be supplied with liquefied gas is connected to the liquid line and at a point where the liquid branch line of the replacement storage tank is connected to the liquid line. It is provided between points to be connected.

Preferably, the gas line is provided with a compressor for compressing the evaporative gas and a heater for heating the evaporative gas compressed by the compressor, and a storage ready to be supplied with the liquefied gas. Compresses and heats the evaporative gas that is transferred from the tank to the replacement storage tank.

Preferably, the storage tanks ready to receive the supply of liquefied gas are a cool-down storage tank subject to a cool-down step in which the replacement step has been completed, and a commissioning liquefied gas supply in which the cool-down step has been completed. a supply storage tank to be processed, said cool-down storage tank being supplied with liquefied gas through said stripping branch line and said supply storage tank being supplied with liquefied gas through said liquid branch line. supplied.

Preferably, the replacement storage tank includes a first replacement storage tank to which the evaporative gas is supplied from the cool-down storage tank, and a second replacement storage tank to which the evaporative gas is supplied from the supply storage tank. Prepare.

To achieve the above objects, one embodiment of the present invention provides a system for supplying liquefied gas fuel in a vessel for supplying liquefied gas fuel from a liquefied gas supply vessel to a liquefied gas fueled vessel having two or more liquefied gas fuel tanks. A liquid branch line or stripping branch connected from the liquefied gas supply ship to the first fuel tank, comprising a first fuel tank for storing liquefied gas fuel and a second fuel tank for storing liquefied gas fuel. A liquefied gas fuel supply system for a ship, which supplies liquefied gas fuel using a line and supplies evaporative gas discharged from the first fuel tank as replacement gas for the second fuel tank through a gas line. I will provide a.

Preferably, the gas line is provided with a compressor for compressing the evaporative gas and a heater for heating the evaporative gas compressed by the compressor, and the gas is transferred from the first fuel tank to the second fuel tank. The evaporative gas is compressed, heated and supplied.

Preferably, a liquid line connecting the liquid branch lines, a point where the liquid branch line for the first fuel tank branches off from the liquid line, and a point where the liquid branch line for the second fuel tank branches off from the liquid line. and an isolation valve provided between.

Preferably, when the liquefied gas is supplied to the first fuel tank using the liquid branch line, the gas discharged from the second fuel tank is discharged through the liquid branch line connected to the second fuel tank. Evacuate and the isolation valve is closed.

Preferably, the fuel tank further comprises a first connecting line connecting a liquid branch line of the second fuel tank and a rear end of the isolation valve.

Preferably, when the liquefied gas is supplied to the first fuel tank through the liquid branch line, the gas discharged from the second fuel tank is discharged from the vent mast through the liquid line and the first connecting line. be done.

The liquefied gas supply system and method for ships and the liquefied gas fuel supply system according to the present invention can The evaporative gas generated in the LNG fuel tank can be treated inside the LNG carrier or the like itself without being recovered to the LNG supply source.

In particular, during the commissioning phase of an LNG carrier or LNG-fueled ship, or when supplying LNG while the LNG storage tanks or LNG fuel tanks are empty, the evaporative emissions generated during the LNG cool-down process and the LNG supply process It can be processed on the LNG carrier or LNG fueled vessel itself without recovery on the LNG bunkering vessel.

Therefore, LNG bunkering vessels can be used at sea to supply LNG for commissioning of LNG carriers or LNG fueled vessels. It also eliminates the need for forced vaporization of the LNG for the replacement step. In addition, evaporative gas treatment and LNG supply can be carried out simultaneously on a ship that supplies LNG.

1 is a conceptual diagram simply showing a liquefied gas supply system in a ship according to an embodiment of the present invention; FIG. FIG. 10 is a drawing showing the state of fluid circulation during cool-down of the fourth storage tank in the liquefied gas supply system for ships according to the embodiment of the present invention. FIG. 10 is a drawing showing the state of fluid circulation during cool-down of the fourth storage tank in the liquefied gas supply system for ships according to the embodiment of the present invention. FIG. 4 is a drawing showing a fluid circulation state when LNG is supplied to a fourth storage tank in the liquefied gas supply system for a ship according to one embodiment of the present invention; FIG. FIG. 4 is a drawing showing a fluid circulation state when LNG is supplied to a fourth storage tank in the liquefied gas supply system for a ship according to one embodiment of the present invention; FIG. FIG. 3 is a conceptual diagram simply showing a liquefied gas fuel supply system in a ship according to another embodiment of the present invention. FIG. 10 is a drawing showing the state of fluid circulation during cooling down of the first fuel tank in a liquefied gas fuel supply system for a ship according to another embodiment of the present invention. FIG. 10 is a drawing showing the state of fluid circulation during cooling down of the first fuel tank in a liquefied gas fuel supply system for a ship according to another embodiment of the present invention. FIG. 5 is a drawing showing a fluid circulation state when LNG is supplied to the first fuel tank in a liquefied gas fuel supply system for a ship according to another embodiment of the present invention; FIG. 5 is a drawing showing a fluid circulation state when LNG is supplied to the first fuel tank in a liquefied gas fuel supply system for a ship according to another embodiment of the present invention;

For a full understanding of the operational advantages of the invention and the objectives achieved by its practice, reference should be made to the accompanying drawings which illustrate preferred embodiments of the invention.

Hereinafter, configurations and operations according to preferred embodiments of the present invention will be described in detail with reference to the drawings. Here, regarding the reference numerals attached to the constituent elements described in each drawing, the same constituent elements are denoted by the same reference numerals as much as possible in other drawings. It should be noted that the embodiments described below can be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below.

In the embodiments described later, the liquefied gas is a gas that can be liquefied at a low temperature and transported, such as LNG (Liquefied Natural Gas), LEG (Liquefied Ethane Gas), LPG (Liquefied Petroleum Gas), and liquefied ethylene gas. Gas (Liquefied Ethylene Gas), liquefied Propylene Gas (Liquefied Propylene Gas), etc. are illustrated. Also, the liquefied gas may be liquefied carbon dioxide, liquefied hydrogen, liquefied ammonia, or the like. However, in the embodiments described later, application of liquefied natural gas (LNG), which is a representative liquefied gas, will be described.

In addition, the ship in the embodiment described later will be described by taking a liquefied natural gas carrier (LNG Carrier) for transporting liquefied natural gas as cargo as an example, but the present invention is provided with a storage tank for storing liquefied natural gas. Vessels equipped with liquefied gas storage tanks such as LNG FSRU (Floating Storage Regasification Unit), LNG FPSO (Floating Production Storage Offloading), LNG RV (Regasification Vessel), and LNG fueled vessels in which liquefied gas is supplied to the engine as fuel. can be applied to

Further, storage tanks in the embodiments described later include all cargo tanks, fuel tanks, etc., regardless of name, as long as they are liquefied gas tanks capable of storing liquefied gas.

1 to 10, a liquefied gas supply system and method for a ship, and a liquefied gas fuel supply system for a ship according to an embodiment of the present invention will be described below.

The ship according to this embodiment includes a plurality of LNG storage tanks (T1, T2, T3, T4, etc.) and an LNG bunker to supply LNG to the plurality of LNG storage tanks (T1, T2, T3, T4, etc.) It comprises a manifold (L) connected to a vessel or terminal supplying LNG, such as a ring vessel, and fluid transfer piping connecting a plurality of LNG storage tanks (T1, T2, T3, T4, etc.) and the manifold (L). .

The fluid transfer piping includes a liquefied gas line that supplies LNG to any one of a plurality of LNG storage tanks (T1, T2, T3, T4, etc.) from a ship that supplies LNG, and any one It includes a gas discharge line for discharging evaporative emissions generated in supplying LNG to the LNG storage tank, and a gas supply line for supplying the generated evaporative emissions to one or more other LNG storage tanks.

The liquefied gas lines in this embodiment to be described later include a liquid line (LL) and liquid branch lines (LL1, LL2, LL3, LL4, etc.), a stripping line (SL) and stripping branch lines (SL1, SL2, SL3, SL4, etc.).

In addition, the gas discharge line is composed of a gas line (GL), gas branch lines (GL1, GL2, GL3, GL4, etc.), a first connect line (CL1) and a second connect line (CL2), and a liquid line ( LL) and liquid branch lines (LL1, LL2, LL3, LL4, etc.), the gas discharge lines when the gas flows are the liquid line (LL) and the liquid branch lines (LL1, LL2, LL3, LL4, etc.), and the second 1 connect line (CL1) and a second connect line (CL2).

Furthermore, the gas supply line is composed of a gas line (GL) and gas branch lines (GL1, GL2, GL3, GL4, etc.).

Regarding the liquefied gas supply system and method for a ship according to the present embodiment, the LNG bunkering ship is connected to the LNG bunkering ship via the manifold (L) to the LNG storage tank (T1, T2, T3, T4, etc.) An example in which LNG is supplied will be described.

Further, in this embodiment, an example of supplying LNG for initial cool-down and LNG for trial operation from the LNG bunkering vessel to the LNG storage tank for the purpose of trial operation of the vessel will be described. However, the present invention is not limited to the above embodiments, and two or more LNG fuel tanks are provided when LNG is supplied to the LNG fuel tank of the LNG fueled ship or when LNG is supplied to the LNG storage tank. Various aspects are possible when supplying LNG to an LNG fuel tank in an LNG fueled ship.

Furthermore, although not shown, the ship in this embodiment uses LNG stored in LNG storage tanks (T1, T2, T3, T4, etc.) as fuel, a main engine that generates propulsion energy, and an LNG storage tank. A power generation engine that uses LNG stored in tanks (T1, T2, T3, T4, etc.) as fuel to generate electrical energy, and LNG stored in LNG storage tanks (T1, T2, T3, T4, etc.) Evaporation gas generated by natural vaporization is supplied as fuel for the main engine and the power generation engine, and re-liquefaction for re-liquefying the evaporative gas and collecting it in LNG storage tanks (T1, T2, T3, T4, etc.) and an evaporative emission processing section (100, 200, etc.) for treating the evaporative emission or the evaporative emission tripped from the engine.

Furthermore, a plurality of LNG storage tanks (T1, T2, T3, T4, etc.) can be installed, and in this embodiment, as shown in FIGS. 1 to 5, four LNG storage tanks (T1, T2, T3, T4) are installed. Note that the number of LNG storage tanks is not limited to four. In this embodiment, the LNG storage tanks installed in order from the bow to the stern are the first storage tank (T1), the second storage tank (T2), the third storage tank (T3), and the fourth storage tank. Name the tank (T4).

Manifolds (L) can be provided separately for a liquid through which a liquid state fluid flows and a manifold for vapor through which a gaseous state fluid flows. , only the manifold (L) for the liquid necessary for explaining this embodiment is shown.

Fluid transfer piping includes liquid lines (LL) and stripping lines (SL) that transfer LNG in liquid state between manifold (L) and LNG storage tanks (T1, T2, T3, T4), and stripping lines (SL) in gaseous state. It includes a gas line (GL) for transporting natural gas.

The liquid lines (LL) and stripping lines (SL) are connected to the manifold (L) via liquid crossover lines (LC).

When unloading LNG from LNG storage tanks (T1, T2, T3, T4) through manifold (L) and into LNG storage tanks (T1, T2, T3, T4) through manifold (L) During LNG loading, the LNG is transferred through a liquid line (LL).

In addition, for the purpose of ejecting LNG into the LNG storage tanks (T1, T2, T3, T4) through the manifold (L), and for the purpose of stripping the LNG in the LNG storage tanks (T1, T2, T3, T4) When transferring LNG, LNG is distributed through a stripping line (SL).

The vessel in this embodiment comprises lines branching from the liquid line (LL) to each LNG storage tank (T1, T2, T3, T4). This line includes a first liquid line (LL1) branching from the liquid line (LL) to the first storage tank (T1), and a second liquid line branching from the liquid line (LL) to the second storage tank (T2). (LL2), a third liquid line (LL3) branching from the liquid line (LL) to a third storage tank (T3), and a fourth liquid branching from the liquid line (LL) to a fourth storage tank (T4). line (LL4).

The first to fourth liquid lines (LL1, LL2, LL3, LL4) extend toward the bottom inside the LNG storage tanks (T1, T2, T3, T4), respectively.

The vessel in this embodiment also comprises a branching line from the stripping line (SL) to each LNG storage tank (T1, T2, T3, T4). This line consists of a first stripping line (SL1) branching from the stripping line (SL) into a first storage tank (T1), a second branching from the stripping line (SL) into a second storage tank (T2). Two stripping lines (SL2), a third stripping line (SL3) branching from the stripping line (SL) to a third storage tank (T3), and from the stripping line (SL) to a fourth storage tank (T4). is a fourth stripping line (SL4) branching off to .

The first to fourth stripping lines (SL1, SL2, SL3, SL4) are respectively connected to liquid domes or gas domes of LNG storage tanks (T1, T2, T3, T4), specifically LNG storage It is connected to the injection nozzles installed at the top of the tanks (T1, T2, T3, T4). Therefore, the LNG transferred to the LNG storage tanks (T1, T2, T3, T4) through the first to fourth stripping lines (SL1, SL2, SL3, SL4) is ) from the top to the bottom.

Also, the first to fourth stripping lines (SL1, SL2, SL3, SL4) may extend to the bottom inside the LNG storage tanks (T1, T2, T3, T4), respectively.

The gas line (GL) in this embodiment connects the LNG storage tanks (T1, T2, T3, T4) via the evaporative gas treatment units (100, 200, etc.). 1 to 5 show only the gas line (GL) through which the evaporative gas discharged from the LNG storage tanks (T1, T2, T3, T4) flows, but the fluid transfer pipe is the gas line (GL) In addition, the gaseous natural gas further comprises a vapor line through which it flows between the LNG storage tanks (T1, T2, T3, T4), the manifold (L), and the evaporative emission processing units (100, 200, etc.) can be done.

The gas lines (GL) comprise branch lines connected from the gas dome of each LNG storage tank (T1, T2, T3, T4) to the vapor treatment section (100, 200, etc.). This branch line includes a first gas line (GL1) branching from the gas line (GL) to the first storage tank (T1), and a second gas line (GL1) branching from the gas line (GL) to the second storage tank (T2). line (GL2), a third gas line (GL3) branching from the gas line (GL) to a third storage tank (T3), and a fourth branching from the gas line (GL) to a fourth storage tank (T4). A gas line (GL4).

In addition, although not shown, the evaporative gas processing unit (100, 200, etc.) compresses the evaporative gas generated in the LNG storage tanks (T1, T2, T3, T4) and supplies the evaporative gas fuel as engine fuel. It can be provided with a supply unit, a reliquefaction unit that reliquefies the evaporative gas and recovers it in LNG storage tanks (T1, T2, T3, T4), and a GCU (Gas Combustion Unit) that combusts the evaporative gas.

In addition, among the evaporative gas processing units (100, 200, etc.), the reference numeral 100 is a compressor for pressurizing the evaporative gas generated in the LNG storage tanks (T1, T2, T3, T4), and the reference numeral 200 is the compressor. (100) is a heater that heats the compressed evaporative gas.

Furthermore, although not shown, the first to fourth gas branch lines (GL1, GL2, GL3, GL4) can each be connected to a vent mast (VM) that releases evaporative gas to the atmosphere. By doing so, the evaporative gas can also be vented via a vent mast (VM) as required.

In this embodiment, the second connect line (CL2) connects the liquid line (LL) and the vent mast (VM).

The second connect line (CL2) not only connects the liquid line (LL) and the vent mast (VM), but also connects the liquid line (LL) and the gas dome of the first storage tank (T1). can.

The above-described configuration is the basic configuration applied to the LNG carrier, and the present embodiment follows this basic configuration and evaporates gas generated when LNG is supplied from the LNG bunkering ship to the ship in the present embodiment. proposed a system and method for processing on board the LNG bunkering vessel without returning it to the LNG bunkering vessel.

In the embodiments described later, the case of supplying LNG to the fourth storage tank (T4) will be described, but the present invention is not limited to the above case. For example, it is equally applicable when supplying LNG to other cool-down steps or other LNG storage tanks (T1, T2, T3).

According to this embodiment, the cooling-down process and replacement process, and the supply process and replacement process of a plurality of LNG storage tanks (T1, T2, T3, T4, etc.) can be performed simultaneously.

For example, it is possible to cool down any one storage tank that has completed the replacement process, heat the evaporative gas generated while cooling down the storage tank, and supply it as the replacement gas for the other one storage tank. .

Alternatively, LNG can be supplied to a storage tank that has undergone a cool-down process, and the evaporative gas generated while supplying LNG can be heated and supplied as replacement gas for another storage tank.

First, referring to FIGS. 2 and 3, an initial cool-down method for LNG storage tanks (T1, T2, T3, T4, etc.) will be described. In this embodiment, the fourth storage tank (T4) is used as the storage tank to be cooled down.

The vessel in this embodiment is connected to the LNG bunkering vessel via a manifold (L). LNG cooling down the fourth storage tank (T4) from the LNG bunkering vessel flows through the liquid crossover line (LC), the stripping line (SL) and the fourth stripping line (SL4), and the fourth storage tank (T4) and supplied.

When LNG for cooling down is supplied to the fourth storage tank (T4), a large amount of evaporative gas is generated in the fourth storage tank (T4). At this time, the evaporative gas generated in the fourth storage tank (T4) passes through the fourth gas line (GL4), the gas line (GL), and the third gas line (GL3) to the third storage tank ( T3) is supplied as a replacement gas. Thus, the replacement step of the third storage tank (T3) is performed simultaneously with the implementation of the cooling down step of the fourth storage tank (T4).

The evaporative gas discharged from the fourth storage tank (T4) is compressed by the compressor (100), heated by the heater (200), and then supplied to the third storage tank (T3) as replacement gas. .

As an example, in a 173,400 m ³ class LNG carrier, when utilizing about 6-8 MT/hr of gas, the replacement process takes about 6 hours per storage tank. In this embodiment, the evaporative gas discharged from the cool-down LNG storage tank that performs the cool-down process is heated by a heater (200), which is one of the basic components installed on the ship, It is supplied as a replacement gas to a replacement LNG storage tank in which the replacement step is performed.

That is, in the present embodiment, the cooling down step of the fourth storage tank (T4) is performed, and the replacement step of the third storage tank (T3) arranged adjacent to the fourth storage tank (T4) is performed. .

As mentioned above, the empty tank is filled with an inert gas due to tank construction and safety concerns, but when the third storage tank (T3) is supplied with replacement gas, the third storage tank (T3) The inert gas filled inside T3) is pushed out and discharged through the third liquid line (LL3).

That is, when performing the replacement step of the third storage tank (T3) at the same time as the cooling down step of the fourth storage tank (T4), the inert gas from the third storage tank (T3) flows into the third liquid line (LL3). discharged through

The inert gas discharged through the third liquid line (LL3) is transferred to the vent mast (VM) through the liquid line (LL) and the second connect line (CL2).

That is, at the same time that LNG for cooling down is supplied to the fourth storage tank (T4) through the slipping line (SL), the inert gas is transferred to the vent mast (VM) through the liquid line (LL).

On the other hand, as shown in FIGS. 2 and 3, an additional configuration described later is added to the basic configuration described above, and the evaporative gas generated when LNG is supplied from the LNG bunkering ship to the ship in this embodiment is removed from the LNG bunkering ship. It can also be processed onboard the ship without being sent back to the ship.

That is, in this embodiment, as an additional configuration, an isolation valve (IV) that shuts off the liquid line (LL) and a liquid line (LL) branched and connected to each LNG storage tank (T1, T2, T3, T4) a first connect line (CL1) connected to each liquid branch line (LL1, LL2, LL3, LL4) bypassing the isolation valve (IV), wherein the isolation valve (IV) is connected to the liquid line At (LL), the connection point of the liquid crossover line (LC) and the first branch to the bow side of the connection point of the liquid crossover line (LC) and the second storage tank (T2) are connected to the second storage tank (T2). 2 liquid line (LL2).

In this case, the inert gas discharged through the third liquid line (LL3) is transferred to the vent mast (VM) through the first connect line (CL1), the liquid line (LL) and the second connect line (CL2). .

On the other hand, it is also possible to directly connect the third liquid line (LL3) and the vent mast (VM) without connecting the first connect line (CL1) and the second connect line (CL2) to the liquid line (LL). In this case, the total length of the first and second connect lines (CL1, CL2) is 50 m at maximum when using 200A standard piping based on a 173 km class ³ ship.

As an example, the first connect line (CL1) is connected to a portion of the third liquid line (L3) located on the stern side of the isolation valve (IV) provided in the liquid line (LL).

In addition, the isolation valve (IV) first branches to the bow side from the connection point where the liquid crossover line (LC) connects to the liquid line (LL), and is connected to the second storage tank (T2). 2 It is installed in the part of the liquid line (LL) up to the branch point of the liquid line (LL2).

In addition, the isolation valve (IV) has a connection point where the first connect line (CL1) is connected to the liquid line (LL) and a connection point where the liquid crossover line (LC) is connected to the liquid line (LL). placed in between.

When the first connect line (CL1) is provided, the LNG for cooling down is supplied to the fourth storage tank (T4) through the stripping line (SL), and at the same time, the first connect line (CL1) and the liquid line (LL ) to the vent mast (VM). At this time, the isolation valve (IV) is closed to cut off the portion of the liquid line (LL) on the side where the isolation valve (IV) is located.

On the other hand, as shown in FIG. 3, the isolation valve (IV) can also be provided at the connection point between the liquid crossover line (LC) and the liquid line (LL). A directional valve can be employed.

If the isolation valve (IV) is a three-way valve, as shown in FIG. When carrying out the process, the isolation valve (IV) is opened on the side communicating with the third storage tank (T3) and the vent mast (VM), and closed on the side communicating with the liquid crossover line (LC).

Thus, when performing the replacement step of the third storage tank (T3) at the same time as performing the cooling down step of the fourth storage tank (T4), the isolation valve (IV) is controlled and the liquid crossover line (LC ) and the stripping line (SL) are communicated, while the liquid crossover line (LC) and the liquid line (LL) are disconnected.

Next, with reference to FIGS. 4 and 5, a method for supplying LNG to ships in this embodiment will be described. In this embodiment, a method of supplying LNG to the fourth storage tank (T4) will be described as a representative example.

For example, LNG is supplied to any one of the storage tanks ready to be supplied with LNG after the cooldown process and the replacement process, and the evaporative gas generated from the LNG storage tank is heated while supplying LNG. can also be supplied as a replacement gas to one of the LNG storage tanks.

The amount of evaporative gas generated while performing the cool-down process of the fourth storage tank (T4) is about 120 tons/hr, which is enough to complete the replacement process of the third storage tank (T3). amount. Also, after completing the replacement step of the third storage tank (T3), in an amount sufficient to subsequently carry out part of the replacement step of a further storage tank, for example the second storage tank (T2). be.

Therefore, when LNG is supplied to the fourth storage tank (T4) after completing the cool-down process, the second storage tank (T2) is replaced with the evaporative gas generated in the fourth storage tank (T4). This will be described with an example.

That is, as described above, when the fourth storage tank (T4) is cooled down, the replacement process of the third storage tank (T3) is completed. After that, the evaporative gas generated in the fourth storage tank (T4), which has completed the cool-down process, is transferred to the second storage tank (T2) and/or the first storage tank (T1), that is, the replacement process of another storage tank. can be used to implement

In this case, when the LNG is supplied to the fourth storage tank (T4) where the cool-down process is completed, the isolation valve (IV) diverts the evaporative gas discharged from the fourth storage tank (T4) to the second storage tank (T2). ) or as a replacement gas for the first storage tank (T1), the portion through which the LNG flows and the portion through which the replacement gas flows are cut off from each other in the liquid line (LL).

The vessel in this embodiment is connected to the LNG bunkering vessel via a manifold (L). LNG for trial operation supplied from the LNG bunkering vessel to the 4th storage tank (T4) is sent to the 4th storage tank (T4) through the liquid crossover line (LC), the liquid line (LL) and the 4th liquid line (LL4). supplied.

When LNG is supplied to the fourth storage tank (T4), a large amount of evaporative gas is generated within the fourth storage tank (T4). At this time, the evaporative gas generated in the fourth storage tank (T4) is transferred to the second storage tank (T2) through the fourth gas line (GL4), the gas line (GL) and the second gas line (GL2). and the step of supplying LNG to the fourth storage tank (T4) can be performed simultaneously with the replacement step of the second storage tank (T2).

The evaporative gas discharged from the fourth storage tank (T4) is compressed by the compressor (100), heated by the heater (200), and then supplied to the second storage tank (T2) as replacement gas. can be done.

That is, according to one embodiment of the present invention, when LNG is supplied to any one of the supply LNG storage tanks (T4), the supply LNG storage tank (T4) is cooled down simultaneously with the replacement It is possible to carry out the replacement process of further replacement LNG storage tanks (T2, T1) other than the LNG storage tank (T3) for which the process has already been completed.

As mentioned above, empty LNG storage tanks are filled with inert gas due to LNG storage tank construction and safety concerns. The filled inert gas is pushed out and discharged through the second liquid line (LL2).

According to the present embodiment, when LNG is supplied to the fourth storage tank (T4) and the replacement step of the second storage tank (T2) is performed at the same time, inert gas is released from the second storage tank (T2). It is discharged through the second liquid line (LL2).

The inert gas discharged through the second liquid line (LL2) is transferred to the vent mast (VM) through the liquid line (LL) and the second connect line (CL2).

That is, using the liquid line (LL), LNG is supplied to the fourth storage tank (T4), which is a storage tank located on the stern side, and at the same time, the isolation valve (IV) is placed on the fore side. Through a portion of the liquid line (LL) located inert gas is transferred to the vent mast (VM).

At this time, the isolation valve (IV) is closed, and the part of the liquid line (LL) located on the stern side across the isolation valve (IV) and the part of the liquid line (LL) located on the bow side block each other.

In addition, the isolation valve (IV) can be installed at a connection point where the liquid crossover line (LC) is connected to the liquid line (LL), as shown in FIG. A three-way valve, for example, can be adopted as the isolation valve (IV) in this case.

If the isolation valve (IV) is a 3-way valve, as shown in FIG. 5, then the replacement step of the second storage tank (T2) at the same time as supplying LNG to the fourth storage tank (T4), as described above. When performing, the isolation valve (IV) communicates the part located on the stern side across the isolation valve (IV) in the liquid crossover line (LC) and the liquid line (LL), and the liquid crossover line ( LC) and the stripping line (SL) are controlled to be disconnected.

By the above control of the isolation valve (IV), the liquid crossover line (LC) and the liquid line (LL) are communicated only with the fourth storage tank (T4) side and are not communicated with the second storage tank (T2) side. .

That is, when performing the replacement step of the second storage tank (T2) at the same time as supplying LNG to the fourth storage tank (T4), the LNG supply to the fourth storage tank (T4) and the second storage tank ( The inert gas discharge from T2) is all done through the liquid line (LL), but the isolation valve (IV) is placed across the isolation valve (IV) so that the LNG flows from the manifold (L) to the fourth storage tank ( T4) and the passage of inert gas from the second storage tank (T2) to the vent mast (VM) are isolated from each other.

Next, a liquefied gas fuel supply system for a ship according to another embodiment of the present invention will be described with reference to FIGS. 6 to 10. FIG.

In other embodiments of the present invention, the vessel includes two or more LNG fuel tanks (T1, T2, etc.) and an LNG tank, such as an LNG bunkering vessel, to supply the LNG fuel tanks (T1, T2, etc.) with LNG. and a fluid transfer line connecting the LNG fuel tanks (T1, T2, etc.) to the manifold (L).

The fluid transfer pipe is a liquefied gas line that supplies LNG to any one of two or more LNG fuel tanks (T1, T2, etc.) from a ship that supplies LNG. , a gas discharge line for discharging the evaporative gas generated when LNG is supplied to any one of the LNG fuel tanks (T1, T2, etc.), and one or more other LNG storage tanks (T1, T2, etc.) ).

The liquefied gas line in this embodiment, which will be described later, comprises a liquid line (LL), liquid branch lines (LL1, LL2, etc.), and a stripping line (SL) and stripping branch lines (SL1, SL2, etc.).

The gas discharge line consists of a gas line (GL), gas branch lines (GL1, GL2, etc.), and a connect line (CL), and gas flows through the liquid line (LL) and the liquid branch lines (LL1, LL2, etc.). The gas discharge line in this case consists of a liquid line (LL), a liquid branch line (LL1, LL2, etc.), and a connect line (CL).

The gas supply line is composed of a gas line (GL) and gas branch lines (GL1, GL2, etc.).

The vessel in this embodiment may comprise two or more LNG fuel tanks (T1, T2, etc.), and if the vessel is an LNG carrier, one or more LNG cargo tanks, etc. be able to.

The vessel in this embodiment is connected to an LNG bunkering vessel, and when LNG is supplied from the LNG bunkering vessel to LNG fuel tanks (T1, T2, etc.) via a manifold (L), i.e., LNG bunkering A case of treating evaporative gas will be described as an example.

Further, regarding this embodiment, when supplying LNG for initial cool-down or LNG for trial operation from the LNG bunkering ship to the LNG fuel tank for the purpose of bunkering the ship, or when supplying (filling) LNG fuel will be described as an example. However, the present invention is not limited to the above embodiments, and can be applied to an LNG-fueled ship provided with two or more LNG fuel tanks, for example, when LNG is supplied to the LNG fuel tanks.

In addition, although not shown, the ship in this embodiment uses LNG stored in LNG fuel tanks (T1, T2, etc.) as fuel, a main engine that generates propulsion energy, and LNG fuel tanks (T1, T2, etc.). LNG stored in T2, etc.) is used as fuel to generate electric energy, and the main engine uses the evaporative gas generated by natural vaporization of the LNG stored in the LNG fuel tank (T1, T2, etc.). A fuel supply unit that supplies fuel for the power generation engine, a re-liquefaction unit that re-liquefies the evaporative gas and recovers it in the LNG fuel tank (T1, T2, etc.), and a gas processing unit that processes the evaporative gas or the evaporative gas tripped from the engine. (100, 200, etc.).

Also, in this embodiment, as shown in FIGS. 6 to 10, two LNG fuel tanks (T1, T2) are provided as an example. However, the invention is not limited to this case.

In this embodiment, the LNG fuel tank installed at the stern and the LNG fuel tank installed at the bow are named the first fuel tank (T1) and the second fuel tank (T2), respectively.

Manifolds (L) are separately provided for liquid through which fluid in liquid state and for vapor through which fluid in gaseous state flows. Only the manifold (L) for liquids is shown.

The fluid transfer pipes are a liquid line (LL) and a stripping line (SL) for transferring LNG in a liquid state between the manifold (L) and the LNG fuel tanks (T1, T2), and a natural gas in a gaseous state. including a gas line (GL) to

The liquid line (LL) and stripping line (SL) are connected to the manifold (L) via a liquid crossover line (LC).

When unloading LNG from LNG fuel tanks (T1, T2) via manifold (L) and when loading LNG to LNG fuel tanks (T1, T2) via manifold (L) LNG is transferred via a liquid line (LL).

In addition, when transferring LNG for the purpose of supplying LNG to the LNG fuel tanks (T1, T2) via the manifold (L) and for the purpose of stripping the LNG in the LNG fuel tanks (T1, T2), the LNG is Distribute the ripping line (SL).

The ship in this embodiment further includes liquid branch lines (LL1, LL2) branching from the liquid line (LL) toward the LNG fuel tanks (T1, T2). That is, a first liquid line (LL1) branching from the liquid line (LL) to the first fuel tank (T1) and a second liquid line (LL1) branching from the liquid line (LL) to the second fuel tank (T2) LL2).

The first and second liquid lines (LL1, LL2) can extend toward the bottom inside the LNG fuel tanks (T1, T2), respectively.

In addition, the ship in this embodiment further includes stripping branch lines (SL1, SL2) branching from the stripping line (SL) to the LNG fuel tanks (T1, T2). That is, a first stripping line (SL1) branching from the stripping line (SL) to the first fuel tank (T1), and a second stripping line (SL1) branching from the stripping line (SL) to the second fuel tank (T2). and a stripping line (SL2).

The first and second stripping lines (SL1, SL2) are respectively connected to the liquid dome or gas dome of the LNG fuel tanks (T1, T2) and installed on top of the LNG fuel tanks (T1, T2). connected to the injection nozzle.

That is, the LNG transferred to the first and second LNG fuel tanks (T1, T2) through the first and second stripping lines (SL1, SL2) is transferred to the first and second LNG fuel tanks (T1, T2) respectively. It is supplied by jetting from the upper part to the lower part.

Also, the first and second stripping lines (SL1, SL2) can extend to the bottom inside the first and second LNG fuel tanks (T1, T2), respectively.

The gas line (GL) in this embodiment is provided with an evaporative gas processing section (100, 200, etc.). 6 to 10 show only the gas line (GL) through which the evaporative gas discharged from the first and second LNG fuel tanks (T1, T2) flows. It is also possible to further provide a vapor line for circulating between the first and second LNG fuel tanks (T1, T2), the manifold (L), and the evaporative emission treatment units (100, 200, etc.).

The gas line (GL) includes gas branch lines (GL1, GL2) connected from the respective gas domes of the first and second LNG fuel tanks (T1, T2) to the evaporative emission treatment section (100, 200, etc.). More specifically, a first gas line (GL1) branching from the gas line (GL) to the first fuel tank (T1) and a second gas line (GL1) branching from the gas line (GL) to the second fuel tank (T2) 2 gas line (GL2).

Also, although not shown, the evaporative gas processing unit (100, 200, etc.) compresses the evaporative gas generated in the first and second LNG fuel tanks (T1, T2), and supplies the evaporative gas fuel as engine fuel. A supply unit, a re-liquefaction unit that re-liquefies evaporative gas and recovers LNG in the first and second LNG fuel tanks (T1, T2), and a GCU (Gas Combustion Unit) that burns the evaporative gas. .

The evaporative gas processing unit (100, 200, etc.) includes a compressor (100) for compressing the evaporative gas generated in the first and second LNG fuel tanks (T1, T2) and the evaporative gas compressed by the compressor (100). A heater (200) for heating may further be provided.

Also, although not shown, the first and second gas lines (GL1, GL2) can be respectively connected to a vent mast (VM) that releases evaporative gas to the atmosphere. In this case, evaporative emissions can be vented via a vent mast (VM) as needed.

The liquefied gas fuel supply system in the ship of this embodiment further includes a connect line (CL) that connects the liquid line (LL) and the vent mast (VM).

A connect line (CL) connects the liquid line (LL) and the vent mast (VM). The connect line (CL) can also connect the liquid line (LL) and the gas dome of the first fuel tank (T1).

The configuration described above is the basic configuration, and the present embodiment follows this basic configuration and returns the evaporative gas generated when LNG is supplied from the LNG bunkering ship to the ship in the present embodiment to the LNG bunkering ship. It is a system that can be processed onboard a ship without

The present embodiment will be described by taking as an example the supply of LNG to the first fuel tank (T1), but the present invention is not limited to the above embodiment, and other cool-down steps or the The same can be applied when supplying LNG to the first and second LNG fuel tanks (T1, T2).

According to this embodiment, the cooling down process, the replacement process, and the supply process and the replacement process of two or more LNG fuel tanks (T1, T2, etc.) can be performed simultaneously.

For example, cool down any one of the LNG fuel tanks (T1, etc.) that has completed the replacement process, heat the evaporative gas generated at this time, and supply it to another LNG fuel tank (T2, etc.) as a replacement gas. do.

In addition, LNG is supplied to the LNG fuel tank (T1, etc.) that has finished the cool-down process, the evaporative gas generated while supplying LNG is heated, and the heated evaporative gas is transferred to another LNG fuel tank (T2, etc.) can also be supplied as a replacement gas to

A cool-down process for the LNG fuel tanks (T1, T2) will be described with reference to FIGS. 7 and 8. FIG. In this embodiment, the case where the first fuel tank (T1) is cooled down as the LNG fuel tank to be cooled down will be described as a typical example.

The vessel in this embodiment is connected to the LNG bunkering vessel via a manifold (L). Cooling down the first fuel tank (T1) from the LNG bunkering vessel LNG flows through the liquid crossover line (LC), the stripping line (SL) and the first stripping line (SL1) to the first fuel tank (T1 ) and fed.

When LNG for cooling down is supplied to the first fuel tank (T1), a large amount of evaporative gas is generated in the first fuel tank (T1). At this time, the evaporative gas generated in the first fuel tank (T1) is transferred to the second fuel tank (T2) through the first gas line (GL1), the gas line (GL) and the second gas line (GL2). supply as By doing so, the replacement process for the second fuel tank (T2) can be performed simultaneously with the cool-down process for the first fuel tank (T1).

Also, the evaporative gas discharged from the first fuel tank (T1) is compressed by the compressor (100), heated by the heater (200), and then supplied to the second fuel tank (T2) as replacement gas. be done.

The replacement process takes about 6 hours per LNG fuel tank, for example, for a 173,400 m ³ class LNG carrier, utilizing about 6-8 MT/hr of gas. According to this embodiment, the evaporative gas discharged from the first fuel tank (T1) in which the cool-down process is performed is heated by the heater (200), which is one of the basic components installed in the ship. , the heated evaporative gas is supplied to the second fuel tank (T2) as replacement gas.

That is, according to the present embodiment, at the same time as cooling down any one of the cool-down LNG fuel tanks (T1), the Another LNG fuel tank (T2) replacement process can be implemented.

As described above, empty LNG fuel tanks are filled with inert gas due to LNG fuel tank construction and safety concerns. The inert gas filled inside the second fuel tank (T2) is pushed out and discharged through the second liquid line (LL2).

According to the present embodiment, when the cooling-down process of the first fuel tank (T1) and the replacement process of the second fuel tank (T2) are carried out simultaneously, the inert gas is released from the second fuel tank (T2) into the second liquid. It is discharged through line (LL2).

The inert gas discharged through the second liquid line (LL2) is transferred to the vent mast (VM) through the liquid line (LL) and the connect line (CL).

That is, LNG for cooling down is supplied to the first fuel tank (T1) through the stripping line (SL), and the inert gas discharged from the second fuel tank (T2) is supplied through the second liquid line (LL2). Transfer to vent mast (VM).

In this embodiment, as shown in FIGS. 7 and 8, an additional configuration is added to the basic configuration described above, and the evaporative gas generated when supplying LNG from the LNG bunkering ship to the ship in this embodiment is reduced. It can also be processed on board without being returned to the LNG bunkering vessel.

As an additional configuration, the present embodiment may further include an isolation valve (IV) installed in the middle of the liquid line (LL) to shut off the liquid line (LL).

The connect line (CL) can also be connected to the vent mast (VM) by connecting to the first and second liquid branch lines (LL1, LL2) instead of the liquid line (LL). At this time, the total length of the connect line (CL) is 50m maximum when using 200A standard piping based on a 173km class ³ ship.

In the embodiment shown in FIG. 7, the isolation valve (IV) is installed in the liquid line (LL) between the connection point of the liquid crossover line (LC) and the branch point of the second liquid line (LL2). ing.

Also, in the embodiment shown in FIG. 8, an isolation valve (IV) is provided at the connection point where the liquid crossover line (LC) is connected to the liquid line (LL).

In either embodiment, inert gas is transferred to the vent mast (VM) through the liquid line (LL) at the same time that LNG is supplied to the first fuel tank (T1) through the stripping line (SL). At this time, the isolation valve (IV) is closed to cut off the liquid line (LL) and control is performed so that the inert gas does not flow into the first fuel tank (T1).

Further, in the embodiment shown in FIG. 8, isolation valve (IV) may employ a three-way valve.

In this case, as described above, when performing the cooling-down process of the first fuel tank (T1) and performing the replacement process of the second fuel tank (T2), the second fuel tank (T2) communicates with the vent mast (VM) is opened, and the side communicated with the liquid crossover line (LC) is closed.

Thus, when performing the cooling-down process of the first fuel tank (T1) and simultaneously performing the replacement process of the second fuel tank (T2), the isolation valve (IV) is controlled and the crossover line (LC) is and the stripping line (SL) are communicated, while the crossover line (LC) and the liquid line (LL) are disconnected.

Next, with reference to FIGS. 9 and 10, a case of supplying LNG to a ship in this embodiment will be described. This embodiment will be described by taking as a representative example the case where LNG is supplied to the first fuel tank (T1).

For example, LNG is supplied to any one of the LNG fuel tanks (T1, T2, etc.) that are ready to supply LNG after the cooldown process and the replacement process, and the LNG fuel tanks (T1, T2, etc.) are supplied with LNG. etc.) and supply the heated evaporative gas to another LNG fuel tank (T1, T2, etc.) as replacement gas.

The amount of evaporative gas generated during the cooling down process of the first fuel tank (T1) is about 120 tons/hr, which is sufficient to complete the replacement process of the second fuel tank (T2). is. It is also the amount that allows the subsequent replacement process of another LNG fuel tank or cargo tank to be carried out after completing the replacement process of the second fuel tank (T2).

In this embodiment, when LNG is supplied to the first fuel tank (T1), the evaporative gas generated in the first fuel tank (T1) is used to replace the second fuel tank (T2). To explain, as mentioned above, the replacement process of the adjacently arranged second fuel tank (T2) is completed when the cool-down process of the first fuel tank (T1) is performed. After that, when LNG is supplied to the first fuel tank (T1) that has completed the cool-down process, the evaporative gas generated in the first fuel tank (T1) is replaced during the cool-down process of the first fuel tank (T1). It is used to carry out the replacement process of liquefied gas tanks such as LNG fuel tanks and LNG storage tanks other than the second LNG fuel tank (T2) where was carried out.

The isolation valve (IV) in the present embodiment diverts the evaporative gas discharged from the first fuel tank (T1) to the second fuel tank ( In order to supply T2) or another LNG fuel tank or the like as replacement gas, the direction in which LNG flows and the direction in which replacement gas flows are cut off from each other.

The vessel in this embodiment is connected to the LNG bunkering vessel via a manifold (L). LNG supplied from the LNG bunkering ship to the first fuel tank (T1) is supplied to the first fuel tank (T1) through the liquid crossover line (LC), the liquid line (LL) and the first liquid line (LL1). .

When LNG is supplied to the first fuel tank (T1), a large amount of evaporative gas is generated in the first fuel tank (T1). At this time, the evaporative gas generated in the first fuel tank (T1) is transferred to the second fuel tank (T2) through the first gas line (GL1), the gas line (GL) and the second gas line (GL2). supplied as By doing so, it is possible to carry out the step of supplying LNG to the first fuel tank (T1) and at the same time carry out the step of replacing the second fuel tank (T2).

Further, the evaporative gas discharged from the first fuel tank (T1) is compressed by the compressor (100) and heated by the heater (200). is supplied as a replacement gas to

That is, according to the present embodiment, when LNG is supplied to the first fuel tank (T1) and the cool-down process is performed before the supply process of the first fuel tank (T1), the replacement process is already completed. The process of replacing the second fuel tank (T2) other than the LNG fuel tank (T1) can be carried out at the same time.

As described above, empty LNG fuel tanks are filled with inert gas due to construction and safety issues of LNG fuel tanks. The inert gas filled with is pushed out and discharged through the second liquid line (LL2).

According to the present embodiment, when LNG is supplied to the first fuel tank (T1) and the replacement process of the second fuel tank (T2) is performed at the same time, inert gas is released from the second fuel tank (T2). It is discharged through the second liquid line (LL2).

The inert gas discharged through the second liquid line (LL2) is transferred to the vent mast (VM) through the liquid line (LL) and the connect line (CL).

For example, at the same time as supplying LNG to the first fuel tank (T1) located on the stern side through the liquid line (LL), the liquid line (LL) located on the bow side across the isolation valve (IV) Partially inert gas is transferred to the vent mast (VM).

At this time, the isolation valve (IV) is closed, and the part of the liquid line (LL) located on the stern side across the isolation valve (IV) and the part of the liquid line (LL) located on the bow side block each other.

On the other hand, in the embodiment shown in FIG. 10, the isolation valve (IV) employs a three-way valve provided at the connection point where the liquid crossover line (LC) is connected to the liquid line (LL).

If the isolation valve (IV) is a three-way valve, as described above, when LNG is supplied to the first fuel tank (T1) and the replacement process of the second fuel tank (T2) is performed, the isolation valve (IV ) communicates between the liquid crossover line (LC) and the portion of the liquid line (LL) located on the branching side of the first liquid line (LL1), and on the branching side of the second liquid line (LL2). It is controlled to be out of communication with the part of the liquid line (LL) where it is located.

By controlling the isolation valve (IV) in this way, the liquid crossover line (LC) communicates only with the portion of the liquid line (LL) located on the side of the first fuel tank (T1) and the second fuel tank (T2). ) side of the liquid line (LL) is disconnected.

Thus, when performing the replacement step of the second fuel tank (T2) at the same time as supplying LNG to the first fuel tank (T1), the supply of LNG to the first fuel tank (T1) and the second fuel All of the discharge of inert gas from the tank (T2) is performed through the liquid line (LL), and the isolation valve (IV) allows the LNG to flow from the manifold (L) to the first fuel tank through the isolation valve (IV). (T1) and the passage of inert gas from the second fuel tank (T2) to the vent mast (VM) are cut off and isolated from each other.

Although the embodiments according to the present invention have been described above, it should be understood that the present invention can be embodied in other specific forms without departing from the spirit or category of the invention other than the above-described embodiments. , are self-explanatory to those of ordinary skill in the art. Accordingly, the above-described embodiments are exemplary rather than limiting. That is, the present invention is not limited to the above-described embodiments, and can be modified as appropriate within the scope of the appended claims and their equivalents.

Claims (22)

In a liquefied gas supply system in a ship that supplies liquefied gas from a ship that supplies liquefied gas to a ship equipped with a plurality of liquefied gas tanks,
a liquefied gas line for supplying liquefied gas to any one of the plurality of liquefied gas tanks; and a gas discharge line for discharging evaporative gas generated when supplying liquefied gas to any one of the liquefied gas tanks; and gas supply lines for supplying evaporative gas to one or more other said liquefied gas tanks. further comprising a heater for heating the evaporative gas discharged through the gas discharge line;
2. The liquefied gas supply system for ships according to claim 1, wherein the evaporative gas heated by said heater is supplied to one or more other said liquefied gas tanks through said gas supply line. 2. The liquefied gas supply system for ships according to claim 1, wherein evaporative gas generated when supplying liquefied gas to any one of said liquefied gas tanks is supplied to another one of said liquefied gas tanks. 2. The liquefied gas supply system for ships according to claim 1, wherein evaporative gas generated when supplying liquefied gas to any one of said liquefied gas tanks is supplied to all other said liquefied gas tanks. a liquid crossover line through which the liquefied gas is transferred from a vessel supplying the liquefied gas;
The liquefied gas line includes a liquid line capable of transferring liquefied gas and a plurality of branch lines branched from the liquid line and connected to each of the liquefied gas tanks,
2. The liquefied gas supply system for a ship according to claim 1, wherein the liquefied gas flowing through the liquefied gas line via the liquid crossover line is supplied to each of the liquefied gas tanks via the branch line. In the liquid line,
one or more isolation valves are provided that, when liquefied gas is supplied to any one of the liquefied gas tanks, shut off the liquid line to prevent the supply of liquefied gas to one or more of the other liquefied gas tanks; A liquefied gas supply system for a ship according to claim 5. The isolation valve is installed between the connection point of the liquid crossover line and the liquid line and one of the branch points where the branch line first connected to the liquefied gas tank from this connection point branches off from the liquid line. 7. A liquefied gas supply system for ships according to claim 6, wherein: The gas supply line discharges evaporative gas generated when supplying liquefied gas to any one of the liquefied gas tanks, and supplies the discharged evaporative gas to one or more of the other liquefied gas tanks;
The gas discharged from the liquefied gas tank to which the evaporative gas is supplied is discharged from the liquefied gas tank to which the evaporative gas is supplied through the liquefied gas line,
In the liquefied gas line, an isolation provided between the liquefied gas tank to which the liquefied gas is supplied and the liquefied gas tank to which the evaporative gas is supplied, and isolates the liquefied gas circulation part and the evaporative gas circulation path from each other 2. The liquefied gas supply system in a marine vessel of claim 1, further comprising: a valve. a manifold connected to the vessel that supplies liquefied gas; and a liquid crossover line that connects the manifold and the liquefied gas line;
9. The liquefied gas supply system for ships according to claim 8, wherein said isolation valve is a three-way valve provided at a connection point between said liquid crossover line and said liquefied gas line. a vent mast that releases evaporative gas to the atmosphere; and a connect line that connects the liquefied gas line and the vent mast;
The gas discharged from the liquefied gas tank to which the evaporative gas is supplied is an inert gas,
9. A liquefied gas supply system in a marine vessel according to claim 8, wherein said inert gas is transferred to the vent mast from any one of said liquefied gas tanks supplied with liquefied gas. In a method for supplying liquefied gas to a ship that supplies liquefied gas from a ship that supplies liquefied gas to a ship equipped with a plurality of liquefied gas tanks,
a liquefied gas supply step of supplying the liquefied gas from a vessel supplying the liquefied gas to any one of the liquefied gas tanks; and an evaporative gas discharge of discharging the evaporative gas generated in any one of the liquefied gas tanks by the liquefied gas supply step. and a replacement gas supply step of supplying the evaporative gas discharged in the evaporative gas discharge step to one or more other liquefied gas tanks among the plurality of liquefied gas tanks; supply method. 12. The method of supplying liquefied gas in a ship according to claim 11, wherein the evaporative gas discharged in said evaporative gas discharge step is heated and the heated evaporative gas is supplied to one or more other said liquefied gas tanks. 12. The method of supplying liquefied gas in a ship according to claim 11, wherein the liquefied gas supplying step supplies evaporative gas generated in any one of the liquefied gas tanks to another one of the liquefied gas tanks. 12. The method of supplying liquefied gas in a ship according to claim 11, wherein the liquefied gas supplying step supplies the evaporative gas generated in any one of the liquefied gas tanks to all of the other liquefied gas tanks. 12. The method of supplying liquefied gas in a ship according to claim 11, wherein in said liquefied gas supplying step, supply of liquefied gas to one or more other said liquefied gas tanks is cut off. An inert gas discharge step of discharging the inert gas filled in the liquefied gas tank to which the evaporative gas is supplied by the replacement gas supply step;
12. The method of supplying liquefied gas in a ship according to claim 11, wherein in the inert gas discharging step, the inert gas is discharged through a line through which the liquefied gas is supplied to the liquefied gas tank. The inert gas discharge step includes:
17. The liquefied gas in a ship according to claim 16, further comprising: a separation step of isolating a portion through which the liquefied gas flows to the liquefied gas tank and a portion through which the inert gas flows in the line that supplies the liquefied gas to the liquefied gas tank. supply method. In a liquefied gas supply system in a ship that supplies liquefied gas from a ship that supplies liquefied gas to a ship equipped with a liquefied gas fuel tank,
a first fuel tank storing liquefied gas fuel; and a second fuel tank storing liquefied gas fuel; a liquid branch line or stripping connected from said vessel supplying liquefied gas to said first fuel tank. A liquefied gas fuel supply system for a ship, which supplies liquefied gas fuel to the first fuel tank through a branch line and simultaneously supplies evaporative gas discharged from the first fuel tank to the second fuel tank as replacement gas. . further comprising a gas line through which evaporative gas is transferred,
The gas line includes
a compressor for compressing the evaporative gas; and a heater for heating the evaporative gas compressed by the compressor;
19. The liquefied gas fuel supply system for a ship according to claim 18, wherein the evaporative gas transferred from the first fuel tank to the second fuel tank is compressed and heated before being supplied. a liquid line capable of transferring liquefied gas fuel; a plurality of liquid branch lines branching from the liquid line; a branching point in the liquid line where the liquid branch line connected to the first fuel tank branches; 19. The liquefied gas fuel supply system for a marine vessel according to claim 18, further comprising: an isolation valve provided between a branch point where a liquid branch line connected to the second fuel tank branches. When the liquefied gas is supplied to the first fuel tank through the liquid branch line connected to the first fuel tank, the isolation valve is closed and the gas discharged from the second fuel tank is discharged from the second fuel tank. 21. A system for supplying liquefied gas fuel in a marine vessel as claimed in claim 20, wherein the liquid is discharged through the liquid branch line connected to the tank. a vent mast that releases gas into the atmosphere; and a connect line that connects the liquid line and the vent mast,
When liquefied gas is supplied to the first fuel tank through the liquid branch line connected to the first fuel tank, the gas discharged from the second fuel tank passes through the liquid line and the connect line to the vent. 22. A system for supplying liquefied gas fuel in a marine vessel according to claim 21, wherein the system discharges to the mast.

Images