JP2016118301A - Liquefied gas supply connecting structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the discharge of a liquefied gas remaining in a line to the atmosphere at line cut-off by a small quantity of a purge gas, in a system which sends a liquefied gas through a detachable line.SOLUTION: An outlet connecting part 17 having a liquefied gas supply valve 19, a connecting joint 20 and a purge gas supply valve 21 which communicate with one another are arranged at a liquefied gas supply facility 12 side. An inlet connecting part 18 having a liquefied gas on/off-valve 29 and a connecting joint 28 which communicates with the liquefied gas on/off-valve 29 and is connected to the connecting joint 20 is arranged at a ship 11 side. The supply of a liquefied gas is stopped by closing the liquefied gas supply valve 19. A purge gas is supplied to the outlet connecting part 17 and the inlet connecting part 18 by opening the purge gas supply valve 21. It is monitored whether or not the liquefied gas is purged from both the connecting parts 17, 18. After the confirmation of the finish of the purge, the liquefied gas on/off-valve 29 is closed, and the connection of the connecting joints 20, 28 is released.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a system for sending liquefied gas, and more particularly to a system for purging vaporized gas fuel from a pipe when sending liquefied gas fuel to transport equipment.

  In recent years, LNG fueled ships that use liquefied natural gas, which has a lower environmental load, as fuel have been promoted. The bunker work in the LNG fuel ship is performed by connecting the bunker hose to the ship, but the liquefied natural gas partially boils and vaporizes in the fuel line including the bunker hose due to heat from the outside. Therefore, even if the liquid feeding is stopped, the vaporized natural gas remains in the fuel line, and the residual natural gas is released into the atmosphere when the bunker hose is disconnected. In order to prevent such natural gas from leaking out to the atmosphere, an LNG bunker system that purges the natural gas remaining in the fuel line in advance with nitrogen gas or the like is also known (Patent Document 1).

Special table 2011-503463 gazette

  However, since the conventional purge method purges the entire fuel line, a large amount of purge gas (nitrogen gas) is required. Nevertheless, there is a case where a purge gas facility is not provided when a small facility, or a liquefied gas fuel is supplied from a lorry vehicle or a bunker ship.

  The present invention is a system for delivering liquefied gas through a separable line, and for purging necessary to suppress the release of vaporized liquefied gas remaining in the line and the liquefied gas itself to the atmosphere when the line is separated. The aim is to greatly reduce the amount of gas.

  The liquefied gas supply connection mechanism of the present invention is a liquefied gas supply connection mechanism of a bunker system for supplying liquefied gas to transport equipment, and is provided at the tip of the flexible bunker hose and the bunker hose and communicates with each other. A first connection portion on the side of supplying a liquefied gas comprising a first valve and a first connection joint, a second valve, a purge gas supply valve, and a second valve, and communicated with the first connection; A second connecting portion on the side receiving the supply of the liquefied gas, the second connecting joint comprising a second connecting joint connectable to the joint, the first valve at one end of the main pipe of the first connecting portion, and the first valve at the other end. The second connection joint is provided at one end of the main pipe of the second connection portion, the second connection joint is provided at the other end, and the purge gas is supplied to the first branch pipe of the main pipe of the second connection portion. A valve is provided.

  The first branch of the second connection further comprises a coupling for connecting the purge gas supply valve to the purge gas supply source. The main pipe of the first or second connection portion includes a second branch pipe, and the second branch pipe includes a sampling valve. A purge gas supply source connected to the purge gas supply valve is arranged in the transport equipment.

  The ship according to the present invention is a transport device in the connection mechanism for supplying a liquefied gas, and includes a second connection portion.

  The liquefied gas is liquefied gas fuel, and ships use this liquefied gas as fuel.

  According to the present invention, in a system for sending a liquefied gas through a separable line, it is necessary to suppress the release of the vaporized liquefied gas remaining in the line and the liquefied gas itself to the atmosphere when the line is separated. The amount of purge gas can be greatly reduced.

It is a block diagram which shows the structure of a liquefied fuel bunker system provided with the line connection mechanism which is one Embodiment of this invention.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a block diagram illustrating a configuration of a liquefied gas supply system including a line connection mechanism according to an embodiment of the present invention.

  The liquefied gas supply system 10 of this embodiment is a bunker system that supplies liquefied gas fuel such as LNG to transportation equipment that uses liquefied gas as fuel, such as the LNG fuel ship 11. In the example shown in FIG. 1, an LNG fuel ship moored from a LNG storage tank (liquefied gas storage tank) 13 of a fuel supply facility (liquefied gas supply facility) 12 installed in a harbor through a fuel line (liquefied gas line). The liquefied natural gas (liquefied gas) is supplied to 11 LNG fuel tanks (liquefied gas tank) 15.

  From the LNG storage tank 13, for example, LNG is delivered through a flexible bunker hose 16. An outlet connecting portion 17 is provided at the tip of the bunker hose 16 and is connected to the inlet connecting portion 18 of the LNG fuel ship 11 during bunkering. The outlet connection portion 17 includes, for example, a letter pipe, and a liquefied gas supply valve 19 is provided at one end of the main pipe, and a connection joint 20 is provided at the other end of the main pipe. The branch pipe is provided with a purge gas supply valve 21 and a joint 22.

  The liquefied gas supply valve 19 is connected to the bunker hose 16, and the flow of the liquefied gas supplied from the bunker hose 16 is controlled by opening and closing the liquefied gas supply valve 19. The connection joint 20 is, for example, a flange joint, and is connected to the flange joint of the ship side inlet connection portion 18 during bunkering. The purge gas supply valve 21 is a valve that controls the supply of a purge gas such as nitrogen gas to the clove tube, and can be connected to the purge gas supply equipment 23 via a joint 22 provided at the tip of the branch pipe.

  The purge gas supply equipment 23 is provided in the LNG fuel ship 11 serving as a transport device. For example, nitrogen gas is supplied from a nitrogen gas cylinder (purge gas supply source) 24 loaded on the ship through a fixed pipe 25 and a flexible hose 26 to the outlet connection portion 17. To supply. A joint 27 that can be connected to the joint 22 provided on the branch pipe of the outlet connecting portion 17 is provided at the tip of the flexible hose 26.

  The inlet connecting portion 18 also includes, for example, a letter pipe, and a connecting joint 28 is provided at one end of the main pipe, and a liquefied gas on-off valve 29 is provided at the other end of the main pipe. For example, a sampling valve 30 is provided in the branch pipe. The connection joint 28 is complementary to the connection joint 20 of the outlet connection portion 17, and is a flange in this embodiment. The liquefied gas on-off valve 29 is connected to the inboard LNG fuel tank 15 through the fixed pipe 31.

  Next, a bunker work procedure in the bunker system of this embodiment will be described. In the present embodiment, the liquefied natural gas is supplied from the LNG storage tank 13 to the LNG fuel tank 15 of the LNG fuel ship 11 by connecting the flange joints 20 and 28 and opening the liquefied gas supply valve 19 and the liquefied gas on-off valve 29. To do. The bunkering is ended by closing the liquefied gas supply valve 19, for example, and at this time, the liquefied gas on-off valve 29 is opened, more preferably slightly opened.

  Thereafter, the purge gas supply valve 21 is opened, and nitrogen gas is supplied from the nitrogen gas cylinder 24 of the purge gas supply equipment 23 to the outlet connecting portion 17 through the joints 27 and 22. The joints 22 and 27 may be connected before bunkering starts, during bunkering, or after bunkering ends.

  At this time, the liquefied natural gas and the vaporized natural gas remaining in the outlet connecting portion 17 and the inlet connecting portion 18 are pushed by the nitrogen gas to the LNG fuel tank 15 side through the liquefied gas on-off valve 29 and purged. The operator opens the sampling valve 30 and monitors the completion of the purge by confirming the composition of the gas in the pipe (for example, confirming that the methane gas concentration is sufficiently low). After confirming the completion of purging, the sampling valve 30 is closed, the liquefied gas on-off valve 29 and the purge gas supply valve 21 are closed, and the supply of nitrogen gas (purge gas) is stopped. Then, the couplings 22 and 27 are disconnected, and the outlet connecting portion 17 on the fuel supply facility 12 side is disconnected from the inlet connecting portion 18 on the ship 11 side.

  As described above, according to the present embodiment, it is only necessary to purge between the liquefied gas supply valve at the outlet connecting portion and the liquefied gas on-off valve at the inlet connecting portion, and the amount of gas required for purging can be greatly reduced. . For this reason, it becomes possible to arrange the purge gas supply source on the transportation equipment side, and for example, even when using a small-scale facility that does not have a purge gas supply facility, leakage of liquefied gas fuel can be prevented. .

  The fuel supply facility may be an onshore tank as in the present embodiment, but may be a bunker ship or a tank truck. In this embodiment, the transportation device using liquefied gas fuel is a ship. However, the transportation device is limited to a ship, such as when liquefied gas fuel is transferred from a storage tank to a tank truck, or when liquefied gas fuel is supplied to a rocket. It is not something. The present embodiment can also be used for disconnecting a supply line of liquefied gas that needs to be prevented from being released into the atmosphere, and the liquefied gas is not limited to liquefied gas fuel.

  In this embodiment, the purge gas is supplied from the branch pipe of the connection part on the supply facility side because the purge is performed to the ship side. However, when purging to the supply facility side, the purge gas is supplied from the branch pipe on the ship side. A configuration is also possible. Further, in this embodiment, each valve and joint are communicated with each other using a clove tube, but the both connection portions are not limited to a clove tube, and the number of branches is also limited to this embodiment. is not. It is also possible to omit the sampling valve by adopting another method for sampling. Further, in this embodiment, the purge gas supply valve and the sampling valve are provided in different connecting portions, but both may be provided in the same connecting portion.

  For example, a stop valve is used for each valve of the present embodiment. Valves also exist on the liquefied gas storage tank side and the purge gas supply equipment side, and these valves are closed at the end of bunkering or at the end of purge, but the description thereof is omitted in this embodiment.

  In the present embodiment, a purge gas supply source (nitrogen gas cylinder) is connected to the fixed pipe (25), and the purge gas is supplied to the outlet connecting portion via the flexible hose (26) connected to the fixed pipe. However, the configuration may be such that the fixed pipe (25) is omitted and the purge gas is supplied from the purge gas supply source directly to the outlet connection portion via the flexible hose.

In addition, the following structures may be sufficient as this invention.
That is, the connection mechanism for supplying liquefied gas includes a first connection portion including a first valve, a first connection joint, and a purge gas supply valve that communicate with each other, a second valve, and a second valve. And a second connection portion including a second connection joint that is communicated and is connectable to the first connection joint.

  The first connection portion further includes a joint for connecting the purge gas supply valve to the purge gas supply source. The second connection portion further includes a sampling valve communicated with the second valve and the second connection joint. The purge gas supply source is located in the transport equipment. The first valve is a valve that supplies liquefied gas, and the second valve is a valve that receives liquefied gas.

  The ship of this invention is provided with either one of the 1st or 2nd connection part of the connection mechanism for liquefied gas supply in any one of the said.

  The liquefied gas is a liquefied gas fuel. For example, ships use liquefied gas as fuel.

  The liquefied gas supply connection mechanism disconnecting method of the present invention includes a first connection portion including a first valve, a first connection joint, and a purge gas supply valve that are communicated with each other, a second valve, and a second valve. A liquefied gas supply connection mechanism comprising: a second connecting portion including a second connecting joint connected to the first connecting joint and connected to the first connecting joint; and supplying the liquefied gas by closing the first valve Is stopped, the purge gas supply valve is opened, the purge gas is supplied to the first and second connection portions, and it is monitored whether the liquefied gas has been purged from the first and second connection portions, and the purge is completed. After confirmation, the second valve is closed and the connection of the first and second connection joints is released.

  The second connection further comprises a sampling valve in communication with the second valve and the second connection coupling, and monitoring is performed at the sampling valve. After confirming the completion of the purge, the second valve is closed after the sampling valve is closed. After the liquefied gas supply is stopped, the second valve is opened slightly until the second valve is closed.

10 Liquefied gas supply system 11 LNG fuel ship (transport equipment)
12 Fuel supply facility (liquefied gas supply facility)
13 LNG storage tank (liquefied gas storage tank)
15 LNG fuel tank (liquefied gas tank)
16 Bunker hose (flexible hose)
17 Outlet connection portion 18 Inlet connection portion 19 Liquefied gas supply valve 20 Connection joint 21 Purge gas supply valve 22 Joint 23 Purge gas supply equipment 24 Nitrogen gas cylinder (purge gas supply source)
25 Fixed pipe 26 Flexible hose 27 Joint 28 Connection joint 29 Liquefied gas on-off valve 30 Sampling valve 31 Fixed pipe

Claims (6)

A liquefied gas supply connection mechanism for a bunker system that supplies liquefied gas to transport equipment,
A flexible bunker hose,
A first connecting portion on the side of supplying the liquefied gas, which is provided at a tip of the bunker hose and includes a first valve and a first connecting joint which are communicated with each other;
A second valve on the side that receives the supply of the liquefied gas, comprising a second valve, a purge gas supply valve, and a second connection joint that communicates with the second valve and is connectable to the first connection joint. With a connection part,
The first valve is provided at one end of the main pipe of the first connection portion, and the first connection joint is provided at the other end,
The second valve is provided at one end of the main pipe of the second connection portion, the second connection joint is provided at the other end, and the purge gas supply valve is provided at the first branch pipe of the main pipe of the second connection portion. A connecting mechanism for supplying a liquefied gas, characterized by being provided.   The liquefied gas supply connection mechanism according to claim 1, wherein the first branch pipe of the second connection portion further includes a joint for connecting the purge gas supply valve to a purge gas supply source. .   3. The liquefied gas supply according to claim 1, wherein the main pipe of the first or second connection portion includes a second branch pipe, and the second branch pipe includes a sampling valve. 4. Connection mechanism.   The liquefied gas supply connection mechanism according to any one of claims 1 to 3, wherein a purge gas supply source connected to the purge gas supply valve is disposed in the transport device.   5. The liquefied gas supply connection mechanism according to claim 1, wherein the transport device is a ship and includes the second connection part.   The ship according to claim 5, wherein the liquefied gas is liquefied gas fuel, and the liquefied gas is used as fuel.

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