Liquefied gas storage installation and vessel

Abstract

The liquefied gas storage device of one aspect of the present disclosure has: a storage tank that stores liquefied gas; a suction pipe that has a suction port that suctions the liquefied gas from inside the storage tank and extends from the inside of the storage tank to the outside of the storage tank; an upper pipe that has a suction / discharge port located at an upper portion inside the storage tank and extends from the upper portion inside the storage tank to the outside of the storage tank; a suction pipe first valve that is a first valve provided to the suction pipe; an upper pipe first valve that is a first valve provided to the upper pipe; a connection pipe that connects a portion of the suction pipe on the suction port side than the suction pipe first valve and a portion of the upper pipe on the suction / discharge port side than the upper pipe first valve; and a connection valve provided to the connection pipe.

Description

Technical Field

[0001] This disclosure relates to liquefied gas storage equipment and ships. Background Technology

[0002] Inside a storage tank for liquefied petroleum gas (LPG), the LPG is stored in a state of gas-liquid equilibrium, with the pressure in the gas layer equal to the saturated vapor pressure of the LPG. When the LPG is stored at a temperature lower than the ambient temperature, heat is continuously applied from the outside to the storage tank, causing the LPG to vaporize and produce evaporating gas. By extracting the evaporating gas from the tank and maintaining a constant pressure in the gas layer, the heat intrusion from the outside is balanced by the heat loss as latent heat of vaporization, thus maintaining a constant temperature for the LPG.

[0003] On the other hand, when the storage tank is sealed, preventing the vaporized gas from escaping, the temperature of the liquefied gas gradually rises because there is no heat loss as latent heat of vaporization accompanying evaporation. Consequently, the saturated vapor pressure also increases, and the pressure in the gas layer inside the tank rises along with the liquid temperature. If the temperature of the liquefied gas inside the tank remains uniform, this pressure increase will be relatively slow. However, when a high-temperature layer forms on the liquid surface under the influence of thermal flow, the gas layer and the high-temperature surface layer reach a state of gas-liquid equilibrium, leading to a rapid increase in the pressure in the gas layer inside the tank.

[0004] Therefore, Patent Document 1 proposes a device for spraying liquefied gas drawn by a pump onto the surface of the liquefied gas. According to this device, the formation of a high-temperature layer can be suppressed, and the pressurization of the storage tank can be prevented. Furthermore, in the invention described in Patent Document 1, the device is configured to spray liquefied gas via a discharge pipe connected to a cargo pump, or via a discharge pipe connected to a spray pump.

[0005] Existing technical documents:

[0006] Patent documents:

[0007] Patent Document 1: Japanese Patent Publication No. 2003-247697. Summary of the Invention

[0008] The problem the invention aims to solve:

[0009] However, a "first valve" (sometimes also called a "tank valve") must be installed on the pipeline installed on the storage tank, that is, the pipeline extending from the inside of the storage tank to the outside. The first valve is the valve located on the pipeline extending from the inside of the storage tank to the outside, that is, the valve closest to the suction and discharge ports (including the suction port and the discharge port) located in the storage tank on that pipeline. The first valve can be located inside or outside the storage tank. When the emergency shut-off system is activated, the first valve closes to prevent the liquefied gas and vaporized gas stored in the storage tank from escaping to the outside.

[0010] In the invention described in Patent Document 1, a valve (not shown in Patent Document 1) for switching the input and output of liquefied gas is provided on the discharge pipe connected to the liquefied gas pump in the pipeline through which the injected liquefied gas passes. Furthermore, a valve (not shown in Patent Document 1) for switching whether liquefied gas is injected is provided on the discharge pipe connected to the injection pump. These valves are equivalent to a "first valve," but are all located upstream of the portion of the injected liquefied gas. Therefore, if the system is shut off in an emergency, the first valve closes, and the liquefied gas can no longer be injected. Additionally, in Patent Document 1, the injection (release) of liquefied gas is directed towards the surface of the liquefied gas stored in the storage tank; however, when the storage tank is full, it can also be performed inside the liquefied gas stored in the storage tank (in the liquid). In this case, convection occurs within the liquefied gas stored in the storage tank, which still suppresses the formation of a high-temperature layer.

[0011] In view of the above, the present disclosure aims to provide a liquefied gas storage device and a ship equipped with the liquefied gas storage device that can release liquefied gas to the surface or liquid of liquefied gas even when the first valve is closed.

[0012] Technical means to solve the problem:

[0013] One aspect of the liquefied petroleum gas (LPG) storage device disclosed herein includes: a storage tank for storing LPG; a suction pipe having a suction port for drawing LPG from inside the storage tank and extending from inside the storage tank to the outside of the storage tank; an upper pipe having an upper suction / discharge port located inside the storage tank and extending from the upper part inside the storage tank to the outside of the storage tank; a suction pipe first valve serving as a first valve disposed on the suction pipe; an upper pipe first valve serving as a first valve disposed on the upper pipe; a connecting pipe connecting a portion of the suction pipe closer to the suction port than the first valve of the suction pipe and a portion of the upper pipe closer to the suction / discharge port than the first valve of the upper pipe; and a connecting valve disposed on the connecting pipe, wherein when the first valve of the suction pipe and the first valve of the upper pipe are closed and the connecting valve is opened, LPG drawn from the suction port is released onto the surface of the LPG or into the liquid after sequentially flowing through the suction pipe, the connecting pipe, and the upper pipe. In addition, one type of vessel disclosed herein is equipped with the aforementioned liquefied gas storage equipment.

[0014] According to this structure, even if the first valve of the suction pipe and the first valve of the upper pipe, which serve as the first valves, are closed, as long as the connecting valve is opened, the liquefied gas drawn from the suction port will flow through the suction pipe, the connecting pipe, and the upper pipe, thereby releasing it onto the surface of the liquefied gas or into the liquid. The liquefied gas can also be released onto the surface of the liquefied gas or into the liquid when the first valve is closed.

[0015] Invention effects:

[0016] Based on the above structure, it is possible to provide a liquefied gas storage device and a ship equipped with the liquefied gas storage device that can release liquefied gas to the surface of the liquefied gas or into the liquid even when the first valve is closed. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the liquefied gas storage device according to the first embodiment;

[0018] Figure 2 This is a schematic diagram of the liquefied gas storage device according to the second embodiment;

[0019] Figure 3 This is a schematic diagram of the liquefied gas storage device according to the third embodiment. Detailed Implementation

[0020] (First Implementation)

[0021] The embodiments of this disclosure will now be described. First, the liquefied petroleum gas (LPG) storage device 100 of the first embodiment will be described. The LPG storage device 100 is a device for storing LPG 101. In this embodiment, the LPG storage device 100 is mounted on a ship. However, the LPG storage device 100 may also be installed on land.

[0022] Figure 1 This is a schematic diagram of the liquefied gas storage device 100 according to the first embodiment. Figure 1 As shown, the liquefied gas storage device 100 of this embodiment includes a storage tank 10, a liquefied gas output pipe 11, a suction pump 12, a suction pipe 13, a suction pipe first valve 14, an upper pipe 15, an upper pipe first valve 16, a connecting pipe 18, a connecting valve 19, and an inert gas supply pipe 20. These structural elements will be described in sequence below.

[0023] Storage tank 10 is a tank for storing liquefied petroleum gas (LPG) 101. LPG 101 contains liquefied petroleum gas (LPG), liquefied natural gas (LNG), liquid hydrogen, methanol, liquid ammonia, etc. Thus, LPG 101 can be cryogenic LPG stored at low temperatures, or other types of LPG. The upper part of storage tank 10 is filled with vaporized gas 102 obtained from the vaporization of LPG 101. When a high-temperature layer forms on the surface of LPG 101 under the influence of intruding heat and heat flow from outside storage tank 10, the internal pressure of storage tank 10 increases rapidly because the gas layer and the surface high-temperature layer reach a gas-liquid equilibrium.

[0024] The liquefied petroleum gas (LPG) output pipe 11 is located outside the storage tank 10 and is a pipe that outputs LPG 101 to the outside of the LPG storage device 100. A ship equipped with the LPG storage device 100 of this embodiment has an engine that generates power for propelling the ship. The LPG output pipe 11 outputs LPG 101 to this engine. The engine uses LPG 101 or gas obtained by vaporizing LPG 101 as fuel for propulsion. However, the LPG output pipe 11 may also output LPG 101 to an external storage device, for example, to unload the LPG 101.

[0025] The suction pump 12 is a pump for drawing liquefied gas 101. The suction pump 12 is disposed inside the storage tank 10. In this embodiment, the suction pump 12 is located near the bottom of the storage tank 10 and draws liquefied gas 101 located near the bottom of the storage tank 10. However, some components of the suction pump 12, such as the motor, may also be located outside the storage tank 10.

[0026] The suction pipe 13 is a pipe that extends from the suction pump 12 to the outside of the storage tank 10. The suction pipe 13 draws liquefied gas 101 from the suction port 21 located at the connection with the suction pump 12. In addition, the suction pipe 13 is connected to the liquefied gas output pipe 11. Figure 1 The black arrow indicates the flow of liquefied gas 101 during normal operation (when the emergency shut-off system is not activated). Figure 2 Similarly, in normal operation, by opening the first valve 14 of the suction pipe (described later), the liquefied gas 101 drawn from the suction port 21 is output to the outside of the liquefied gas storage device 100 via the suction pipe 13 and the liquefied gas output pipe 11.

[0027] The first valve 14 of the suction pipeline is the first valve installed in the suction pipeline 13. When the emergency shut-off system is activated under specified conditions, the first valve 14 of the suction pipeline, as the first valve, automatically closes to prevent the liquefied gas 101 stored in the storage tank 10 from being discharged to the outside. However, the first valve 14 of the suction pipeline can also be closed when the emergency shut-off system is not activated.

[0028] The upper pipe 15 extends from the upper part of the storage tank 10 to the outside of the storage tank 10. The upper pipe 15 is connected to the liquefied gas output pipe 11. In addition, the upper pipe 15 includes a distribution section 17 located in the upper part of the storage tank 10. The distribution section 17 extends horizontally and has a plurality of suction and discharge ports 22. The suction and discharge ports 22 can be small-diameter openings formed directly in the distribution section 17, or openings formed at the tips of nozzles such as spray nozzles, shower nozzles, or mist nozzles provided at various locations in the distribution section 17. In normal operation, by opening the upper pipe first valve 16 (described later), the liquefied gas 101 flowing in the liquefied gas output pipe 11 flows into the upper pipe 15 and is released from the suction and discharge ports 22 of the distribution section 17.

[0029] The upper pipeline first valve 16 is the first valve installed on the upper pipeline 15. When the emergency shut-off system is activated under specified conditions, the upper pipeline first valve 16, as the first valve, automatically closes to prevent the liquefied gas stored in the storage tank 10 from being discharged to the outside. However, the upper pipeline first valve 16 can also be closed when the emergency shut-off system is not activated.

[0030] The connecting pipe 18 connects the suction pipe 13 and the upper pipe 15. In this embodiment, the connecting pipe 18 connects the portion of the suction pipe 13 near the suction port 21 (below the first valve 14 of the suction pipe) and the portion of the upper pipe 15 near the suction / discharge port 22 (below the first valve 16 of the upper pipe). In this embodiment, the connecting pipe 18 is located outside the storage tank 10, at a position near the storage tank 10 (below the first valve 14 of the suction pipe and the first valve 16 of the upper pipe).

[0031] The connecting valve 19 is a valve installed on the connecting pipe 18. However, the connecting pipe 18 is not a pipe extending from the inside of the storage tank 10 to the outside; therefore, the connecting valve 19 installed on the connecting pipe 18 is not equivalent to a "first valve." Furthermore, the connecting valve 19 in this embodiment is configured to open and close automatically. For example, it could be configured such that when the emergency shut-off system operates under predetermined conditions, the first valve 14 of the suction pipe and the first valve 16 of the upper pipe are closed, but the connecting valve 19 automatically opens at this time. However, the connecting valve 19 can also be configured to open and close manually.

[0032] The inert gas supply pipe 20 is a pipe used to supply inert gases such as nitrogen to the storage tank 10. In this embodiment, the inert gas supply pipe 20 is directly connected to the storage tank 10. However, the inert gas supply pipe 20 may be configured, for example, to be connected to an upper pipe 15, via which inert gas is supplied to the storage tank 10. The liquefied gas 101 is sprayed in a mist form, and in the event of a possible explosion due to static electricity, supplying inert gas to the storage tank 10 can prevent an explosion.

[0033] The liquefied gas storage device 100 of this embodiment has the structure described above. Therefore, when the emergency shut-off system is in operation and the first valve 14 of the suction pipe and the first valve 16 of the upper pipe, which serve as the first valves, are closed, if the connecting valve 19 is opened, the liquefied gas 101 will... Figure 1 The flow is indicated by the white arrow. That is, when the first valve 14 of the suction pipe and the first valve 16 of the upper pipe are closed and the connecting valve 19 is opened, the liquefied gas 101 drawn from the suction port 21 of the suction pipe 13 flows sequentially through the suction pipe 13, the connecting pipe 18, and the upper pipe 15, and is then released from the suction / discharge port 22 of the distribution section 17 onto the surface of the liquefied gas 101. However, when the storage tank 10 is full, the liquefied gas 101 is released from the suction / discharge port 22 of the distribution section 17 into the liquid of the liquefied gas 101.

[0034] Therefore, according to the liquefied gas storage device 100 of this embodiment, even when the first valve (suction pipe first valve 14 and upper pipe first valve 16) is closed, for example during emergency shut-off system operation, liquefied gas 101 can still be released onto the surface or into the liquid. As a result, when the first valve is closed, the generation of a high-temperature layer on the surface of the liquefied gas 101 can be suppressed, and the rise in internal pressure of the storage tank 10 can be suppressed.

[0035] In addition, such as Figure 1 As shown, in this embodiment, the connecting pipe 18 and connecting valve 19 are located outside the storage tank 10, but they can also be located inside the storage tank 10. In this case, the arrangement of pipes outside the storage tank 10 can be simplified. This is also true in the second and third embodiments described later.

[0036] Furthermore, in this embodiment, the liquefied gas 101 is released via the distribution section 17, but it is also possible to release the liquefied gas 101 directly without going through the distribution section 17. That is, in the liquefied gas storage device 100 of this embodiment, the distribution section 17 can also be omitted. In this case, for example, the lower end of the upper pipe 15 becomes the suction / discharge port 22. This is also the case in the second embodiment described later. Such a structure can also suppress the formation of a high-temperature layer on the surface of the liquefied gas 101 and can suppress the rise of the internal pressure of the storage tank 10.

[0037] (Second Implementation)

[0038] Next, the liquefied gas storage device 200 of the second embodiment will be described. Figure 2 This is a schematic diagram of the liquefied gas storage device 200 according to the second embodiment. For components in the liquefied gas storage device 200 of the second embodiment that are the same as or correspond to components in the liquefied gas storage device 100 of the first embodiment, in... Figure 2 The same symbols are marked in the text, and the explanation is omitted.

[0039] like Figure 2 As shown, the liquefied petroleum gas (LPG) storage device 200 of this embodiment includes multiple (two in this case) suction pumps 12, suction pipes 13, a first valve 14 for the suction pipe, a connecting pipe 18, and a connecting valve 19. The LPG storage device 200 of this embodiment differs from the LPG storage device 100 of the first embodiment in this respect, but otherwise has a structure that is basically the same as that of the LPG storage device 100 of the first embodiment.

[0040] In this embodiment, two suction pipes 13 extend from the suction pump 12 to the outside of the storage tank 10, and after merging at the outside of the storage tank 10, extend to the liquefied gas output pipe 11. The first valve 14 of each suction pipe is located on the portion of the suction pipe 13 closer to the storage tank 10 than the merging point. A connecting pipe 18 connects the portion of each suction pipe 13 closer to the suction port 21 than the first valve 14 of the suction pipe to the portion of the upper pipe 15 closer to the suction / discharge port 22 than the first valve 16 of the upper pipe. Furthermore, a connecting valve 19 is provided in each connecting pipe 18.

[0041] In the liquefied gas storage device 200 of this embodiment, when the first valve (suction pipe first valve 14 and upper pipe first valve 16) is closed, the connecting valve 19 is opened, allowing the liquefied gas 101 drawn from the suction port 21 of the suction pipe 13 to be released from the suction port 22 of the distribution section 17 through the suction pipe 13, the connecting pipe 18, and the upper pipe 15 to the surface or liquid of the liquefied gas 101. Therefore, when the first valve is closed, the generation of a high-temperature layer on the surface of the liquefied gas 101 can be suppressed, and the rise in internal pressure of the storage tank 10 can be suppressed.

[0042] As described above, the liquefied petroleum gas (LPG) storage device 200 of this embodiment includes multiple suction pumps 12, suction pipes 13, suction pipe first valves 14, connecting pipes 18, and connecting valves 19. However, the LPG storage device 200 may also include multiple suction pumps 12, suction pipes 13, and suction pipe first valves 14 on one hand, and one connecting pipe 18 and connecting valve 19 on the other. In this case, to prevent backflow, a check valve can be installed near the suction pump 12 of each suction pipe 13.

[0043] (Third Implementation)

[0044] Next, the liquefied gas storage device 300 of the third embodiment will be described. Figure 3 This is a schematic diagram of the liquefied gas storage device 300 according to the third embodiment. For components in the liquefied gas storage device 300 of the third embodiment that are the same as or correspond to components in the liquefied gas storage device 100 of the first embodiment, in... Figure 3 The same symbols are marked in the text, and the explanation is omitted.

[0045] like Figure 3 As shown, the liquefied gas storage device 300 of this embodiment includes an evaporation gas output pipe 30, and an upper pipe 15 is connected to the evaporation gas output pipe 30. The liquefied gas storage device 300 of this embodiment differs from the liquefied gas storage device 100 of the first embodiment in this respect, but otherwise has a structure that is basically the same as that of the liquefied gas storage device 100 of the first embodiment.

[0046] The evaporation gas output pipe 30 is located outside the storage tank 10 and is a pipe that outputs the evaporation gas 102 generated in the storage tank 10 to the outside of the liquefied gas storage device 100. In addition, when the evaporation gas 102 is used as fuel for the engine, the evaporation gas output pipe 30 can also output the evaporation gas 102 to the engine.

[0047] Furthermore, as described above, the upper pipe 15 is connected to the evaporation gas output pipe 30. Here, Figure 3 The black arrows indicate the flow of liquefied gas 101 and vaporized gas 102 during normal operation (when the emergency shut-off system is not activated). Figure 3 As indicated by the black arrow, the upper pipe 15 is not actually used to release the liquefied gas 101 into the storage tank 10, but rather to draw the evaporated gas 102 generated in the storage tank 10 from the suction port 22 and introduce it into the evaporated gas output pipe 30.

[0048] However, as Figure 3As indicated by the white arrow, if the connecting valve 19 is opened while the first valve 14 of the suction pipe (which serves as the first valve) and the first valve 16 of the upper pipe (which also serve as the first valves), the liquefied gas 101 drawn from the suction port 21 flows sequentially through the suction pipe 13, the connecting pipe 18, and the upper pipe 15, and is then released from the suction / discharge port 22 of the upper pipe 15 onto the surface of the liquefied gas 101 or into the liquid. As a result, the formation of a high-temperature layer on the surface of the liquefied gas 101 can be suppressed, and the rise in internal pressure of the storage tank 10 can be suppressed. Furthermore, the upper pipe 15 may have a distribution section 17 (see reference...). Figure 1 and Figure 2 ).

[0049] The various embodiments have been described above, but they can also be combined. For example, the second embodiment and the third embodiment can be combined. Specifically, one of the two suction pipes 13 in the second embodiment can be connected to the upper pipe 15 of the second embodiment via a connecting pipe 18, and the other suction pipe 13 can be connected to the upper pipe 15 of the third embodiment via a connecting pipe 18. In this case, the connecting pipe 18 can also be located inside the storage tank 10.

[0050] (Summarize)

[0051] As described above, the liquefied petroleum gas (LPG) storage device of the embodiment includes: a storage tank for storing LPG; a suction pipe having a suction port for drawing LPG from inside the storage tank and extending from inside the storage tank to the outside of the storage tank; an upper pipe having a suction / discharge port located at the upper part inside the storage tank and extending from the upper part inside the storage tank to the outside of the storage tank; a suction pipe first valve serving as a first valve provided in the suction pipe; an upper pipe first valve serving as a first valve provided in the upper pipe; a connecting pipe connecting a portion of the suction pipe closer to the suction port than the suction pipe first valve and a portion of the upper pipe closer to the suction / discharge port than the upper pipe first valve; and a connecting valve provided in the connecting pipe, wherein when the suction pipe first valve and the upper pipe first valve are closed and the connecting valve is opened, LPG drawn from the suction port is released onto the surface of the LPG or into the liquid after flowing sequentially through the suction pipe, the connecting pipe, and the upper pipe.

[0052] According to this structure, if the connecting valve is opened when the first valve is closed, liquefied gas can be released onto the surface of the liquefied gas or into the liquid. As a result, the formation of a high-temperature layer on the surface of the liquefied gas can be suppressed, and the rise in internal pressure of the storage tank can be suppressed.

[0053] Furthermore, in the liquefied gas storage device of the embodiment, the upper pipeline includes a distribution section located in the upper part of the storage tank and having multiple suction and discharge ports. When the first valve of the suction pipeline and the first valve of the upper pipeline are closed and the connecting valve is opened, the liquefied gas drawn from the suction port flows sequentially through the suction pipeline, the connecting pipeline, and the upper pipeline, and then the liquefied gas is released from the suction and discharge ports of the distribution section onto the surface of the liquefied gas or into the liquid.

[0054] According to this structure, liquefied gas can be released from multiple locations, thus effectively suppressing the formation of a high-temperature layer on the surface of the liquefied gas.

[0055] Furthermore, the liquefied gas storage device of the embodiment includes an inert gas supply pipeline for supplying inert gas to the storage tank.

[0056] According to this structure, in the event of a potential explosion of liquefied gas, an explosion can be prevented by supplying inert gas into the storage tank from an inert gas supply pipeline.

[0057] Furthermore, in the liquefied gas storage device of the embodiment, the connecting valve may be configured such that when the first valve of the suction pipe and the first valve of the upper pipe are closed, the connecting valve is opened.

[0058] According to this structure, when the emergency shut-off system is in operation, and the first valve of the suction pipe and the first valve of the upper pipe are closed under specified conditions, the liquefied gas can be reliably released to the surface of the liquefied gas or into the liquid, suppressing the rise in internal pressure of the storage tank.

[0059] Furthermore, the liquefied gas storage device of the first and second embodiments also includes a liquefied gas output pipe located outside the storage tank and outputting liquefied gas, wherein the suction pipe and the upper pipe are connected to the liquefied gas output pipe.

[0060] According to this structure, when the first valve is opened, the upper pipe can guide the liquefied gas from the liquefied gas output pipe into the storage tank, and then release it onto the surface of the liquefied gas or into the liquid. Therefore, in normal operation, it is possible to release liquefied gas onto the surface of the liquefied gas while simultaneously using the suction pipe to output the liquefied gas.

[0061] Furthermore, the liquefied gas storage device of the third embodiment also includes: a liquefied gas output pipe located outside the storage tank for outputting liquefied gas; and an evaporation gas output pipe located outside the storage tank for outputting evaporation gas, wherein the suction pipe is connected to the liquefied gas output pipe, and the upper pipe is connected to the evaporation gas output pipe.

[0062] In this structure, the pipe used to output the evaporated gas is used as the upper pipe for releasing liquefied gas into the storage tank. Therefore, there is no need to install a dedicated pipe for outputting liquefied gas, which simplifies the liquefied gas storage equipment.

[0063] Furthermore, the vessel described in the embodiment is equipped with the aforementioned liquefied gas storage equipment.

[0064] Furthermore, the aforementioned vessel is equipped with an engine that generates power to propel the vessel, and the liquefied gas output pipeline can also output liquefied gas to the engine.

[0065] According to this structure, ships can be propelled by an engine that uses liquefied gas or gas formed by the vaporization of liquefied gas as fuel.

[0066] Furthermore, the aforementioned vessel is equipped with an engine that generates power to propel the vessel, and the evaporative gas output pipe can also output liquefied gas to the engine.

[0067] According to this structure, the ship can be propelled by an engine that uses evaporated gas as fuel.

[0068] Symbol explanation:

[0069] 10: Storage tank;

[0070] 11: Liquefied petroleum gas (LPG) output pipeline;

[0071] 13: Suction pipe;

[0072] 14: First valve in the suction pipeline;

[0073] 15: Upper pipe;

[0074] 16: First valve on the upper pipeline;

[0075] 17: Distribution Department;

[0076] 18: Connecting pipes;

[0077] 19: Connecting valve;

[0078] 20: Inert gas supply pipeline;

[0079] 21: Suction port;

[0080] 22: Suction and discharge port;

[0081] 30: Evaporated gas output pipe;

[0082] 100: Liquefied petroleum gas (LPG) storage equipment;

[0083] 101: Liquefied petroleum gas (LPG);

[0084] 102: Evaporated gas;

[0085] 200: Liquefied petroleum gas (LPG) storage equipment;

[0086] 300: Liquefied gas storage equipment.

Claims

1. A liquefied gas storage device, characterized by, Possessing: a storage tank that stores liquefied gas; a suction pipe that has a suction port that sucks liquefied gas from the inside of the storage tank, and extends from the inside of the storage tank to the outside of the storage tank; an upper pipe that has a suction / discharge port located at an upper portion of the storage tank, and extends from the upper portion of the storage tank to the outside of the storage tank; a suction pipe first valve that is provided as a first valve of the suction pipe; an upper pipe first valve that is provided as a first valve of the upper pipe; a connection pipe that connects a portion of the suction pipe on the suction port side than the suction pipe first valve and a portion of the upper pipe on the suction / discharge port side than the upper pipe first valve; and a connection valve that is provided in the connection pipe, when the suction pipe first valve and the upper pipe first valve are closed and the connection valve is opened, liquefied gas sucked from the suction port is released to the surface or liquid of the liquefied gas after sequentially flowing through the suction pipe, the connection pipe, and the upper pipe.

2. The liquefied gas storage apparatus according to claim 1, wherein the upper pipe includes a distribution portion that is located at the upper portion of the storage tank and has a plurality of the suction / discharge ports, when the suction pipe first valve and the upper pipe first valve are closed and the connection valve is opened, liquefied gas sucked from the suction port is released from the suction / discharge ports of the distribution portion to the surface or liquid of the liquefied gas after sequentially flowing through the suction pipe, the connection pipe, and the upper pipe.

3. The liquefied gas storage apparatus according to claim 1 or 2, wherein an inert gas supply pipe that supplies inert gas to the storage tank is provided.

4. The liquefied gas storage apparatus according to claim 1, wherein the connection valve is configured to be automatically opened when the suction pipe first valve and the upper pipe first valve are closed.

5. The liquefied gas storage apparatus according to claim 1, wherein a liquefied gas output pipe that is located outside the storage tank and outputs liquefied gas is further provided, the suction pipe and the upper pipe are connected to the liquefied gas output pipe.

6. The liquefied gas storage apparatus according to claim 1, wherein a liquefied gas output pipe that is located outside the storage tank and outputs liquefied gas is further provided; and a boil-off gas output pipe that is located outside the storage tank and outputs boil-off gas is further provided, the suction pipe is connected to the liquefied gas output pipe, the upper pipe is connected to the boil-off gas output pipe. The liquefied gas storage apparatus according to any one of claims 1 to 6 is provided.

7. A vessel characterised in that, The ship provided with the liquefied gas storage apparatus according to claim 5 or 6, 8. A vessel, characterized in that a motor that generates power for propelling the ship is further provided, the liquefied gas output pipe outputs liquefied gas to the motor. The ship provided with the liquefied gas storage apparatus according to claim 6, 9. A vessel, characterized in that a motor that generates power for propelling the ship is further provided, the boil-off gas output pipe outputs boil-off gas to the motor. ​

Images