Marine LNG fuel tank supply system and control method thereof

Abstract

The present invention provides a marine LNG fuel tank supply system and a control method thereof, comprising a filling unit, a vaporization unit, a fuel unit, a first manifold and a first control valve, a second manifold and a second control valve, a third manifold and a third control valve, and a fourth manifold and a fourth control valve. The fuel unit comprises a fuel tank, wherein a first liquid-phase port of the fuel tank is connected to a liquid-phase filling port of the filling unit via a first manifold, liquid in the filling unit can flow to the first liquid-phase port, and a first control valve is arranged on the first manifold; a gas-phase port of the fuel tank is connected to the gas-phase filling port of the filling unit via a second manifold, and a second control valve is arranged on the second manifold; a first liquid-phase port is connected to an inlet of the vaporization unit via a third manifold, liquid in the fuel tank can flow to the vaporization unit, and a third control valve is arranged on the third manifold; a gas-phase port is connected to an inlet of the vaporization unit via a fourth manifold, and a fourth control valve is arranged on the fourth manifold.

Description

Technical Field

[0001] The present invention relates to the technical field of ship fuel transportation, and in particular to a ship LNG fuel tank supply system and a control method thereof. Background Art

[0002] The shipping industry is a major energy consumer, and the current rate of clean fuel utilization in my country's ships is extremely low. Promoting the use of liquefied natural gas (LNG) as fuel for ships is necessary both to control air pollutants and to adjust my country's energy structure. Currently, LNG-powered ships are typically equipped with LNG storage tanks of a certain capacity, where LNG is primarily stored in liquid form.

[0003] Marine fuel tanks in LNG-powered ships are generally divided into two types: fixed fuel tanks and movable fuel tanks. They are mainly used for filling and storing LNG fuel. The storage tanks are connected to the marine phase change gas supply device through pipelines to transport LNG.

[0004] At present, existing ship LNG fuel tanks are generally arranged individually on board ships. In the supply system using multiple fuel tanks, the supply pipelines are relatively complex and prone to leakage risks. Therefore, the current pipeline layout of ship LNG fuel tanks is not convenient for the use of movable fuel tanks and needs further improvement. Summary of the Invention

[0005] The object of the present invention is to provide a ship LNG fuel tank supply system and a control method thereof, so as to solve the problem that the supply pipeline of the ship LNG fuel tank in the prior art is relatively complicated and it is inconvenient to use the movable fuel tank.

[0006] In order to solve the above technical problems, the present invention provides a marine LNG fuel tank supply system and a control method thereof.

[0007] One aspect of the present invention provides a marine LNG fuel tank supply system, comprising:

[0008] A filling unit, provided with a liquid phase filling port and a gas phase filling port;

[0009] A gasification unit, used for gasifying the fuel, wherein the outlet of the gasification unit is connected to the engine;

[0010] A fuel unit, the fuel unit comprising a fuel tank, the fuel tank being used to store fuel, the fuel tank being provided with a first liquid phase port and a gas phase port;

[0011] a first manifold and a first control valve, wherein the first liquid-phase port and the liquid-phase filling port are connected via the first manifold so that the liquid in the filling unit can flow to the first liquid-phase port; and the first control valve is disposed on the first manifold and configured to control the conduction and cutoff of the first manifold;

[0012] a second manifold and a second control valve, wherein the gas phase port and the gas phase filling port are connected via the second manifold, and the second control valve is provided on the second manifold and configured to control the conduction and cutoff of the second manifold;

[0013] a third manifold and a third control valve, wherein the first liquid-phase port is connected to the inlet of the vaporization unit via the third manifold so that the liquid in the fuel tank can flow to the vaporization unit; and the third control valve is disposed on the third manifold and configured to control the conduction and cutoff of the third manifold;

[0014] A fourth manifold and a fourth control valve, the gas phase port and the inlet of the gasification unit are connected through the fourth manifold, and the fourth control valve is arranged on the fourth manifold and is configured to control the conduction and cutoff of the fourth manifold.

[0015] In one embodiment, the fuel tank is further provided with a second liquid phase port, and the liquid level of the second liquid phase port in the fuel tank is higher than that of the first liquid phase port;

[0016] The second liquid-phase port is communicated with the liquid-phase filling port through the first manifold, so that the liquid in the filling unit can flow into the fuel tank.

[0017] In one embodiment, the fuel unit further includes a first pipeline, a first branch and a second branch, the first liquid phase port is connected to the first confluence pipeline and the third confluence pipeline through the first branch and the first pipeline, and the second liquid phase port is connected to the first confluence pipe through the second branch and the first pipeline.

[0018] In one embodiment, the fuel unit comprises:

[0019] a fifth control valve, provided on the first branch, and configured to control the conduction and cutoff of the first branch;

[0020] a sixth control valve, provided on the second branch, and configured to control the conduction and cutoff of the second branch;

[0021] The seventh control valve is provided on the first pipeline and is configured to control the conduction and cutoff of the first pipeline.

[0022] In one embodiment, the fuel unit further comprises:

[0023] The third branch, the fuel tank is further provided with a fullness measuring port, the fullness measuring port is connected to the third branch;

[0024] A temperature detector is provided on the third branch for detecting the pipe temperature of the third branch, and the first control valve can correspond to the temperature detector.

[0025] In one embodiment, a supercharger is further included, wherein a liquid inlet of the supercharger is connected to the first liquid-phase port through the third manifold to receive the fuel delivered by the fuel tank, and a gas outlet of the supercharger is connected to the gas-phase port to deliver the gasified fuel of the supercharger to the fuel tank;

[0026] It also includes an eighth control valve connected between the liquid inlet end of the supercharger and the third manifold, and configured to control the conduction and cutoff between the liquid inlet end of the supercharger and the third manifold.

[0027] In one embodiment, the fuel unit further includes a pressure detector, which is disposed on the fuel tank and is used to detect the pressure in the fuel tank. The eighth control valve is responsive to the pressure detector.

[0028] In one embodiment, the fuel unit further comprises:

[0029] The second pipeline and the ninth control valve, the second pipeline is connected to the gas phase port, the second pipeline is connected to the second manifold and the fourth manifold, the ninth control valve is arranged on the second pipeline and is configured to control the conduction and cutoff of the second pipeline.

[0030] In one embodiment, there are at least two fuel tanks, and each fuel tank can be filled with fuel through the filling unit and supply fuel to the gasification unit respectively.

[0031] Another aspect of the present invention provides a control method for a marine LNG fuel tank supply system. The control method for a marine LNG fuel tank supply system is applied to the marine LNG fuel tank supply system according to any of the above embodiments. The marine LNG fuel tank supply system has a fuel filling mode and a fuel supply mode. The control method includes:

[0032] In the refueling mode, the liquid-phase refueling port is connected to the first liquid-phase port via the first manifold, the gas-phase refueling port is connected to the gas-phase port via the second manifold, and the third and fourth manifolds are blocked;

[0033] In the fuel supply mode, the first liquid-phase port is connected to the inlet of the gasification unit through the third manifold, the gas-phase port is connected to the inlet of the gasification unit through the fourth manifold, and the first manifold and the second manifold are blocked.

[0034] In one embodiment, the marine LNG fuel tank supply system further includes a gaseous fuel supply mode, and the control method includes:

[0035] In the gaseous fuel supply mode, the gaseous phase port is connected to the inlet of the gasification unit through the fourth manifold, and the first manifold, the second manifold and the third manifold are blocked.

[0036] Beneficial effects:

[0037] The present application discloses a ship LNG fuel tank supply system and a control method thereof. The ship LNG fuel tank supply system includes a filling unit, a gasification unit, a fuel unit, a first manifold and a first control valve, a second manifold and a second control valve, a third manifold and a third control valve, and a fourth manifold and a fourth control valve. Among them, the fuel unit includes a fuel tank for storing fuel. The fuel tank is provided with a first liquid phase port and a gas phase port, which are respectively used for the inlet and outlet of liquid and the balance of gas. The filling unit, as the fuel supply part, includes a liquid phase filling port and a gas phase filling port. The first liquid phase port of the fuel tank is connected to the liquid phase filling port of the filling unit through the first manifold. When the first control valve is opened, the liquid fuel in the filling unit can be directly injected into the fuel tank. Moreover, the gas phase port of the fuel tank is connected to the gas phase filling port of the filling unit through the second manifold to balance the gas phase pressure inside and outside the fuel tank. The gasification unit is used to convert liquid LNG into gas to meet the use requirements of the engine and transport the liquid LNG in the fuel tank to The gasification unit performs gasification. By providing a third manifold to connect the first liquid-phase port with the inlet of the gasification unit, when the third control valve is opened, the liquid fuel in the fuel tank can be transported to the gasification unit for gasification. Furthermore, by providing a fourth manifold to connect the gas-phase port with the inlet of the gasification unit, the gas phase space of the fuel tank can be connected to the gasification unit. Flash gas generated by changes in the temperature and pressure state of the fuel in the fuel tank can also be promptly transported to the gasification unit through the gas-phase port, thereby improving the safety of the marine LNG fuel tank supply system. In this way, the first liquid-phase port provided on the fuel tank can serve as a liquid inlet for storing fuel by connecting to the first manifold, and can also serve as a liquid outlet for supplying fuel to the gasification unit by connecting to the third manifold. The gas-phase port provided on the fuel tank can also be connected to the inlet of the gasification unit through the fourth manifold to transport the flash gas in the fuel tank to the gasification unit. This can reduce the need to open multiple connection ports and connecting pipes on the fuel tank, effectively reducing the complexity of the pipelines; compared with the existing technology, the present application simplifies the technical solution of opening multiple interfaces on the fuel tank, and further simplifies the fuel supply and refueling pipelines, which can reduce the risk of leakage caused by the need to disassemble and install multiple interfaces and pipelines when using mobile fuel tanks, and improve the safety and stability of the ship's LNG fuel tank supply system. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a structural schematic diagram of a marine LNG fuel tank supply system according to one embodiment of the present invention.

[0039] The following are the descriptions of the reference numerals:

[0040] 1 filling unit, 101 liquid phase filling port, 102 gas phase filling port;

[0041] 2 gasification unit;

[0042] 3 fuel unit, 301 first liquid phase port, 302 gas phase port, 303 second liquid phase port, 304 fullness port, 31 fuel tank, 321 first pipeline, 322 second pipeline, 331 first branch, 332 second branch, 333 third branch, 341 fifth control valve, 342 sixth control valve, 343 seventh control valve, 344 ninth control valve, 35 temperature detector;

[0043] 41 first manifold, 42 first control valve;

[0044] 51 second manifold, 52 second control valve;

[0045] 61 third manifold, 62 third control valve;

[0046] 71 fourth manifold, 72 fourth control valve;

[0047] 81 supercharger, 82 eighth control valve;

[0048] 9 engines. DETAILED DESCRIPTION

[0049] Although the present invention is susceptible of being embodied in different forms, only some of the specific embodiments are shown in the drawings and will be described in detail in this specification. It should be understood that this description should be regarded as an exemplary illustration of the principles of the invention and is not intended to limit the invention to that described herein.

[0050] Thus, a feature indicated in this specification is intended to illustrate one of the features of one embodiment of the present invention, rather than to imply that every embodiment of the present invention must have the described feature. Furthermore, it should be noted that this specification describes many features. Although certain features can be combined together to illustrate possible system designs, these features can also be used in other, not explicitly described, combinations. Thus, unless otherwise noted, the described combinations are not intended to be limiting.

[0051] In the embodiments shown in the accompanying drawings, directional indications (such as up, down, left, right, front, and back) used to explain the structure and movement of various components of the present invention are not absolute but relative. These descriptions are applicable when these components are in the positions shown in the accompanying drawings. If the descriptions of the positions of these components are changed, these directional indications will also change accordingly.

[0052] Figure 1 It is a structural schematic diagram of a marine LNG fuel tank supply system according to one embodiment of the present invention.

[0053] See also Figure 1 As shown, an embodiment of one aspect of the present application provides a marine LNG fuel tank supply system, including a filling unit 1, a gasification unit 2, a fuel unit 3, a first manifold 41 and a first control valve 42, a second manifold 51 and a second control valve 52, a third manifold 61 and a third control valve 62, and a fourth manifold 71 and a fourth control valve 72.

[0054] The fuel unit 3 includes a fuel tank 3, which is used to store fuel, and the fuel can be liquefied natural gas (LNG). The fuel tank 3 is provided with a first liquid phase port 301 and a gas phase port 302; the filling unit 1 is provided with a liquid phase filling port 101 and a gas phase filling port 102; the gasification unit 2 is used to gasify the fuel, and the outlet of the gasification unit 2 is used to connect to the engine 9.

[0055] The first liquid-phase port 301 is connected to the liquid-phase filling port 101 via a first manifold 41, allowing liquid from the filling unit 1 to flow to the first liquid-phase port 301. A first control valve 42 is provided on the first manifold 41 and is configured to control the flow of liquid from the first manifold 41. Thus, when the first control valve 42 is open, the first liquid-phase port 301 serves as a liquid inlet for the filling unit 1 to deliver fuel to the fuel tank 3.

[0056] The gas-phase port 302 is connected to the gas-phase filling port 102 via the second manifold 51. A second control valve 52 is provided on the second manifold 51 and is configured to control the flow of the gas-phase filling port 101. When the first control valve 42 and the second control valve 52 are simultaneously opened, the liquid-phase filling port 101 and the gas-phase filling port 102 of the filling unit 1 are connected to the first liquid-phase port 301 and the gas-phase port 302, respectively. This maintains pressure balance within the fuel tank 3 while the filling unit 1 is delivering fuel to the fuel tank 3.

[0057] The first liquid-phase port 301 is connected to the inlet of the vaporization unit 2 via the third manifold 61, allowing liquid from the fuel tank 3 to flow into the vaporization unit 2. A third control valve 62 is provided on the third manifold 61 and is configured to control the flow of fuel from the third manifold 61. Thus, when the third control valve 62 is open, the first liquid-phase port 301 serves as a liquid outlet for the fuel tank 3 to deliver fuel to the vaporization unit 2.

[0058] The gas phase port 302 is connected to the inlet of the gasification unit 2 via a fourth manifold 71. A fourth control valve 72 is disposed on the fourth manifold 71 and is configured to control the opening and closing of the fourth manifold 71. When the fourth control valve 72 is open, it not only connects the gas phase top of the fuel tank 3 with the gasification unit 2, but also allows the flash gas generated by changes in the temperature and pressure of the fuel in the fuel tank 3 to be promptly transported to the gasification unit 2 through the gas phase port 302, thereby preventing excessive pressure within the tank and potentially posing a safety hazard. Furthermore, by transporting the flash gas to the gasification unit 2, the pressure within the fuel tank 3 can be effectively reduced, maintaining stable system operation.

[0059] It should be noted that the first liquid-phase port 301 provided on the fuel tank 3 serves as both a liquid inlet for receiving fuel and an outlet for delivering fuel. By connecting the first liquid-phase port 301 to the liquid-phase filling port 101 of the filling unit 1 via the first manifold 41 and to the inlet of the vaporization unit 2 via the third manifold 61, and by incorporating control valves into the pipelines, the number and complexity of the pipelines are greatly simplified. When the filling unit 1 delivers fuel to the fuel tank 3, the first and second control valves 42 and 52 are opened, and the third and fourth control valves 62 and 72 are closed, allowing the filling unit 1 to enter the fuel tank 3 through the first liquid-phase port 301 for storage. When fuel is needed to supply fuel to the ship's engine 9, the first and second control valves 42 and 52 are closed, and the third and fourth control valves 62 and 72 are opened, allowing the fuel tank 3 to deliver fuel to the vaporization unit 2 through the first liquid-phase port 301.

[0060] The shipboard LNG fuel tank supply system disclosed in the present application reduces the need to open multiple connection ports on the fuel tank 3 and reduces the complexity of the pipeline by designing corresponding connecting pipes and control valves. In the prior art, multiple interfaces are often provided on the fuel tank 3. For example, the fuel tank 3 is provided with at least one liquid inlet and one liquid outlet, and pipelines between the fuel tank 3 and the gasification unit 2 and the filling unit 1. The present application simplifies the technical solution of opening multiple interfaces on the fuel tank 3 and further simplifies the pipelines for fuel supply and filling, making it easier for ships to adopt a fuel supply system with multiple fuel tanks 3. Furthermore, the system can also reduce the risk of leakage caused by the need to disassemble and install multiple interfaces and pipelines when using mobile fuel tanks 3, thereby improving the safety and stability of the shipboard LNG fuel tank supply system and simplifying the process of installing and disassembling the fuel tank 3.

[0061] Furthermore, the ship's LNG fuel tank supply system can also be provided with a control unit, which can be electrically connected to the first control valve 42, the second control valve 52, the third control valve 62 and the fourth control valve 72, thereby controlling the opening or closing of the first control valve 42, the second control valve 52, the third control valve 62 and the fourth control valve 72, so as to automate the ship's LNG fuel tank supply system and improve the intelligence of the system.

[0062] The first control valve 42 , the second control valve 52 , the third control valve 62 , and the fourth control valve 72 may be configured as pneumatic control valves.

[0063] In some embodiments, the fuel tank 3 is further provided with a second liquid phase port 303 , the liquid level height of the second liquid phase port 303 in the fuel tank 3 is higher than the first liquid phase port 301 , the second liquid phase port 303 is connected to the liquid phase filling port 101 through the first manifold 41 , and the liquid in the filling unit 1 can flow into the fuel tank 3 .

[0064] Fuel tank 3 first receives liquid through second liquid-phase port 303, and then opens first liquid-phase port 301 to allow liquid to flow in. Since the LNG stored in fuel tank 3 is a cryogenic liquid, it first enters fuel tank 3 through second liquid-phase port 303, where the liquid level is higher than first liquid-phase port 301. This provides a pre-cooling effect, rapidly cooling fuel tank 3. This allows the LNG to come into contact with the air or walls within fuel tank 3, causing a certain degree of vaporization. This process helps lower the overall temperature within the tank and minimizes evaporation during subsequent liquid inflow.

[0065] Furthermore, the second liquid-phase port 303 may be disposed near the top of the fuel tank 3 , and the first liquid-phase port 301 may be disposed near the bottom of the fuel tank 3 .

[0066] The fuel unit 3 also includes a first pipeline 321, a first branch 331 and a second branch 332. The first liquid phase port 301 is connected to the first manifold 41 and the third manifold 61 through the first branch 331 and the first pipeline 321, and the second liquid phase port 303 is connected to the first manifold 41 through the second branch 332 and the first pipeline 321.

[0067] The first liquid-phase port 301 of the fuel tank 3 is connected to the first branch 331, and then to the first manifold 41 and the third manifold 61 via the first pipe 321. Thus, when the refueling unit 1 delivers fuel to the fuel tank 3, the fuel from the refueling unit 1 can pass through the first manifold 41, the first pipe 321, and the first branch 331, and then enter the fuel tank 3 through the first liquid-phase port 301.

[0068] The second liquid-phase port 303 of the fuel tank 3 is connected to the second branch 332, and then to the first manifold 41 via the first pipe 321. When the refueling unit 1 delivers fuel to the fuel tank 3, the fuel flows through the first manifold 41, the first pipe 321, and the second branch 332, then enters the fuel tank 3 through the second liquid-phase port 303. After cooling the entire fuel tank 3, the fuel then flows through the first manifold 41, the first pipe 321, and the first branch 331 to enter the fuel tank 3.

[0069] Furthermore, the fuel unit 3 includes a fifth control valve 341 . The fifth control valve 341 is provided on the first branch 331 and is configured to control the conduction and cutoff of the first branch 331 .

[0070] The fuel unit 3 includes a sixth control valve 342 , which is provided on the second branch 332 and configured to control the conduction and cutoff of the second branch 332 .

[0071] The fuel unit 3 includes a seventh control valve 343 , which is provided on the first pipeline 321 and is configured to control the conduction and cutoff of the first pipeline 321 .

[0072] When it is necessary to enter the fuel tank 3 through the second liquid phase port 303, the sixth control valve 342 can be opened and the fifth control valve 341 can be closed, so that the liquid in the filling unit 1 can pass through the first pipeline 321 and then flow into the fuel tank 3 through the second branch 332; when it is necessary to enter the fuel tank 3 through the first liquid phase port 301, the fifth control valve 341 can be opened and the sixth control valve 342 can be closed, so that the liquid in the filling unit 1 can pass through the first pipeline 321 and then flow into the fuel tank 3 through the first branch 331.

[0073] It should be noted that, in this embodiment, although a second liquid phase port 303 is added, by coordinating the first pipeline 321, the first branch 331, the second branch 332 and the control valves provided on the corresponding pipelines, the flow direction and flow rate of the fuel can be flexibly adjusted according to the different working conditions and requirements of the ship's LNG fuel tank supply system, thereby reducing the complexity and maintenance cost of the system.

[0074] Specifically, the fifth control valve 341, the sixth control valve 342 and the seventh control valve 343 can be set as pneumatic control valves, and the control unit can be electrically connected to the fifth control valve 341, the sixth control valve 342 and the seventh control valve 343 respectively to control the opening and closing of the fifth control valve 341, the sixth control valve 342 and the seventh control valve 343.

[0075] Manual stop valves may be provided on the first branch 331 and the second branch 332 respectively.

[0076] In some embodiments, the fuel unit 3 further includes a third branch 333 , and the fuel tank 3 is further provided with a full port connected to the third branch 333 .

[0077] It should be noted that the full-fill port can be set at a preset liquid level height in the fuel tank 3. When the fuel level reaches this position, it indicates that the fuel tank 3 is about to be full or is already full. The full-fill port is connected to the first pipe 321 via a third branch 333. When the liquid level reaches the full-fill port, it can overflow through the third branch 333.

[0078] Furthermore, the fuel unit 3 further includes a temperature detector, which is arranged on the third branch 333 and is used to detect the pipeline temperature of the third branch 333 . The first control valve 42 can correspond to the temperature detector 35 .

[0079] Specifically, the temperature detector detects that the temperature of the third branch 333 reaches a first preset value and issues a first signal. The first control valve 42 then closes in response to the first signal. The first preset value refers to a temperature threshold. When the refueling unit 1 fills the fuel tank 3 until the fuel level in the pipe reaches the fill port, the low-temperature fuel can overflow through the fill port into the third branch 333. The temperature detector, located on the third branch 333, detects the pipe temperature there. When the temperature reaches or exceeds the first preset value, it issues a first signal. When the temperature detector issues the first signal, the first control valve 42 receives it and responds accordingly. Typically, closing the first control valve 42, thereby terminating the first manifold 41 connecting the first liquid-phase port 301 and the liquid-phase filling port 101, prevents the refueling unit 1 from further refueling the fuel tank 3.

[0080] The temperature detector can be connected to the control unit. The control unit receives the signal from the temperature detector and controls the opening and closing of the control valves on each pipeline accordingly, thereby realizing the automatic liquid filling process of the fuel unit 3. It can also monitor the filling status of the fuel tank 3 and the temperature condition of the third pipeline in real time, so that the operator can monitor and manage the fuel supply process more conveniently.

[0081] In more detail, the fuel unit 3 may also include a liquid level detection device, which is arranged on the fuel tank 3 and can detect the fuel liquid level height in the fuel tank 3. The liquid level detection device can be connected to the control unit. The control unit can respond quickly when the liquid level height in the fuel tank 3 exceeds the threshold by receiving the signal from the liquid level detection device, thereby ensuring the safety and reliability of the fuel supply.

[0082] Furthermore, a manual shut-off valve may be provided on the third branch 333, and the manual shut-off valve is used to control the conduction and cut-off of the third branch 333, so that when the fuel tank 3 stores fuel normally or transports fuel to the gasification unit 2, the shut-off valve can disconnect the conduction state of the third branch 333.

[0083] In some embodiments, the ship LNG fuel tank supply system also includes a supercharger 81, the liquid inlet end of the supercharger 81 is connected to the first liquid phase port 301 through the third manifold 61 to receive the fuel delivered by the fuel tank 3, and the gas outlet end of the supercharger 81 is connected to the gas phase port 302 so that the fuel gasified by the supercharger 81 can be delivered to the fuel tank 3.

[0084] The liquid inlet of the supercharger 81 is connected to the first liquid-phase port 301 of the fuel tank 3 via the third manifold 61. As the fuel in the fuel tank 3 is continuously used during the process of supplying LNG fuel to the vaporization unit 2, the pressure within the fuel tank 3 decreases, thereby affecting the liquid supply from the fuel tank 3 to the vaporization unit 2. The liquid LNG in the fuel tank 3 then flows out through the first liquid-phase port 301 and enters the supercharger 81 through the third manifold 61. The supercharger 81 vaporizes the liquid LNG and converts it into gaseous LNG fuel. Furthermore, the gas outlet of the supercharger 81 is connected to the gas-phase port 302 of the fuel tank 3, allowing the vaporized LNG fuel to re-enter the top gas phase space within the fuel tank 3 through the gas-phase port 302, thereby providing the necessary gas pressure within the tank.

[0085] The supercharger 81 is provided in the ship's LNG fuel tank supply system, which can not only effectively adjust the gas pressure in the fuel tank 3 so that it fluctuates within a safe range, but also help maintain the normal working state of the fuel tank 3, prevent the problem of normal liquid supply caused by too low pressure, and achieve pressure stabilization of the fuel tank 3.

[0086] Furthermore, an eighth control valve 82 is included. The eighth control valve 82 is connected between the liquid inlet of the supercharger 81 and the third manifold 61 and is configured to control the flow between the liquid inlet of the supercharger 81 and the third manifold 61. Thus, by operating the eighth control valve 82, the fuel flow path from the third manifold 61 to the liquid inlet of the supercharger 81 can be opened or closed.

[0087] Specifically, when the gas pressure in the fuel tank 3 is lower than the normal threshold, the eighth control valve 82 can be opened so that the fuel flowing to the gasification unit 2 through the first liquid phase port 301 can partially flow into the supercharger 81 through the third manifold 61 for gasification; and when supercharging is not required or other operations are required, the eighth control valve 82 can be closed to cut off the flow of fuel to the supercharger 81.

[0088] The fuel unit 3 also includes a pressure detector, which is mounted on the fuel tank 3 and is used to detect the pressure within the fuel tank 3. The eighth control valve 82 is responsive to the pressure detector. The pressure detector allows for real-time and accurate detection of the pressure within the fuel tank 3, and further provides feedback to the system control unit.

[0089] The fourth control valve 72 can respond to the output signal of the pressure detector. When the pressure in the fuel tank 3 exceeds or falls below the preset safety range, the pressure detector will send a corresponding signal. According to the corresponding signal, the control unit can control the closing and opening of the fourth control valve 72.

[0090] Specifically, when the pressure detector detects that the pressure in the fuel tank 3 is lower than the second preset value, the pressure in the fuel tank 3 is relatively low at this time. By opening the eighth control valve 82, the fourth control valve 72 and the fifth control valve 341, the liquid fuel in the fuel tank 3 can be vaporized into gaseous fuel through the supercharger 81 and then flow to the top gas phase space of the fuel tank 3 through the fourth manifold 71, thereby pressurizing the fuel tank 3, which is conducive to maintaining the pressure in the fuel tank 3 within a normal range.

[0091] When the ship's engine gas consumption is small, the pressure in the fuel tank 3 increases due to the evaporation of low-temperature liquid, or in the scenario where the supercharger 81 vaporizes the liquid fuel to increase the pressure in the fuel tank 3, when the pressure in the fuel tank 3 is higher than the third preset value, there is a large amount of flash gas in the gas phase space at the top of the fuel tank 3. At this time, the supercharger 81 is no longer needed to vaporize the liquid fuel flowing out through the first liquid phase port 301. By closing the eighth control valve 82 and the fifth control valve 341 at the same time, the liquid fuel at the bottom of the fuel tank 3 is prevented from flowing to the gasification unit 2, and the fourth control valve 72 is opened. The flash gas at the top of the fuel tank 3 can flow to the vaporizer through the fourth control valve 72 and be supplied to the engine for use, so as to release part of the flash gas and reduce the pressure in the fuel tank 3.

[0092] In some embodiments, the fuel unit 3 also includes a second pipeline 322 and a ninth control valve 344. The second pipeline 322 is connected to the gas phase port 302. The second pipeline 322 is connected to the second manifold 51 and the fourth manifold 71. The ninth control valve 344 is arranged on the second pipeline 322 and is configured to control the conduction and cutoff of the second pipeline 322.

[0093] Among them, the gas phase port 302 of the fuel tank 3 is connected to the second manifold 51 and the fourth manifold 71 respectively through the first pipeline 321. When the gas phase port 302 of the fuel tank 3 needs to be connected to the filling unit 1, it can be opened by controlling the second control valve 52 and the ninth control valve 344 on the second manifold 51, and the fourth control valve 72 of the fourth manifold 71 is closed; when the gas phase port 302 of the fuel tank 3 needs to be connected to the gasification unit 2, it can be opened by controlling the fourth control valve 72 and the ninth control valve 344 of the fourth manifold 71, and the second control valve 52 on the second manifold 51 is closed.

[0094] In some embodiments, there are at least two fuel tanks 3, each of which can be refilled with fuel through the refilling unit 1 and supply fuel to the gasification unit 2. In this way, by increasing the number of fuel tanks 3, even if one fuel tank 3 fails or requires maintenance, the other fuel tanks 3 can still continue to operate, ensuring the continuity and stability of the fuel supply.

[0095] In more detail, when it is necessary to add fuel to one or more of the fuel tanks 3, the seventh control valve 343 of the other fuel tanks 3 can be controlled to be closed, so that the selected fuel tank 3 can be added with fuel; similarly, when it is necessary to use one or more of the fuel tanks 3 to supply fuel to the gasification unit 2, the seventh control valve 343 of the other fuel tanks 3 can be controlled to be closed, so that the selected fuel tank 3 can be used to supply fuel to the gasification unit 2.

[0096] Please see the attached Figure 1 As shown, the fuel unit 3 of the marine LNG fuel tank supply system includes two fuel tanks 3. Specifically, the first pipeline 321 of one fuel tank 3, the first manifold 41, and the third manifold 61 are connected via a tee joint. The first pipeline 321 of the other fuel tank 3 is connected to the third manifold 61. The second pipeline 322 of one fuel tank 3, the second manifold 51, and the fourth manifold 71 are connected via a tee joint. The second pipeline 322 of the other fuel tank 3 is connected to the fourth manifold 71.

[0097] An embodiment of another aspect of the present application provides a control method for a ship's LNG fuel tank supply system, which is applied to the ship's LNG fuel tank supply system of any of the above embodiments, and the ship's LNG fuel tank supply system has a fuel filling mode and a fuel supply mode.

[0098] In the refueling mode, the liquid-phase filling port 101 is connected to the first liquid-phase port 301 through the first manifold 41 , and the gas-phase filling port 102 is connected to the gas-phase port 302 through the second manifold 51 , while the third manifold 61 and the fourth manifold 71 are blocked.

[0099] The refueling mode refers to the transfer of LNG fuel from the refueling unit 1 to the fuel tank 3 for storage. In the refueling mode, the first control valve 42 and the second control valve 52 can be opened, and the third control valve 62 and the fourth control valve 72 can be closed, thereby connecting the liquid-phase refueling port 101 to the first liquid-phase port 301 through the first manifold 41, allowing LNG liquid to enter the fuel tank 3 smoothly.

[0100] Specifically, in refueling mode, sixth control valve 342 is first opened and fifth control valve 341 is closed, allowing liquid from liquid refueling unit 1 to sequentially flow through first manifold 41, first pipeline 321, second branch 332, and second liquid-phase port 303 into fuel tank 3. After cooling the interior of fuel tank 3, sixth control valve 342 is closed and fifth control valve 341 is opened, allowing liquid from liquid refueling unit 1 to sequentially flow through first manifold 41, first pipeline 321, first branch 331, and first liquid-phase port 301 into fuel tank 3. When the temperature detector on third branch 333 detects that the pipeline temperature has reached a first preset value, it generates a first signal, indicating that the fuel in fuel tank 3 has reached a preset liquid level. This signals the closing of first control valve 42, second control valve 52, and fifth control valve 341, completing refueling of fuel tank 3.

[0101] It should be noted that when the fuel unit 3 is provided with at least two fuel tanks 3 , whether to add fuel to the fuel tanks 3 can be controlled by controlling the control valves on the corresponding pipelines, which will not be described in detail here.

[0102] In the fuel supply mode, the first liquid-phase port 301 is connected to the inlet of the gasification unit through the third manifold 61 , the gas-phase port 302 is connected to the inlet of the gasification unit 2 through the fourth manifold 71 , and the first manifold 41 and the second manifold 51 are blocked.

[0103] Specifically, the fuel supply mode refers to the situation where the LNG in the fuel tank 3 is supplied to the vaporization unit 2 for vaporization and supply to the ship's engine. In this mode, the third and fourth control valves 62 and 72 can be opened, while the first and second control valves 42 and 52 can be closed. This allows the first liquid-phase port 301 to communicate with the inlet of the vaporization unit 2 via the third manifold 61, allowing LNG liquid to be delivered to the vaporization unit 2. Simultaneously, the gas-phase port 302 of the fuel tank 3 is connected to the inlet of the vaporization unit 2 via the fourth manifold 71, allowing flash gas generated by changes in temperature and pressure within the fuel tank 3 to be promptly delivered to the vaporization unit 2 via the gas-phase port 302. This connection between the gas-phase port 302 and the inlet of the vaporization unit 2 reduces pressure fluctuations in the fuel tank during the fuel supply process, achieving a more stable supply process.

[0104] Specifically, in the fuel supply mode, the third control valve 62, the fifth control valve 341, the seventh control valve 343 and the ninth control valve 344 are opened, and the sixth control valve 342 is closed, so that the fuel in the fuel tank 3 can flow to the gasification unit 2 through the first branch 331, the first pipeline 321 and the third manifold 61.

[0105] Furthermore, during the process of supplying LNG fuel to the vaporization unit 2, as the fuel in the fuel tank 3 is continuously used, the pressure in the fuel tank 3 will drop, thereby affecting the liquid supply from the fuel tank 3 to the vaporization unit 2. When the pressure detector detects that the pressure in the fuel tank 3 is lower than the second preset value, the eighth control valve 82 can be controlled to open, allowing a portion of the fuel in the fuel tank 3 to flow through the first branch 331, the first pipeline 321, and the third manifold 61 to the booster 81. The booster 81 vaporizes the liquid LNG into gaseous LNG fuel, which then flows through the fourth manifold 71 and the second branch 332 back to the gas phase space at the top of the fuel tank 3, thereby providing the necessary gas pressure in the tank.

[0106] In some embodiments, the marine LNG fuel tank supply system further includes a gaseous fuel supply mode, and the control method includes:

[0107] In the gaseous fuel supply mode, the gaseous phase port 302 is connected to the inlet of the gasification unit 2 through the fourth manifold 71 , and the first manifold 41 , the second manifold 51 and the third manifold 61 are blocked.

[0108] Specifically, under the influence of pressure or temperature, the low-temperature liquid in the fuel tank 3 evaporates and forms flash gas at the top of the tank, or in the scenario where the supercharger 81 vaporizes the liquid fuel to increase the pressure in the fuel tank 3, when the pressure detector detects that the pressure in the fuel tank 3 is higher than the third preset value, there is a large amount of flash gas in the gas phase space at the top of the fuel tank 3. By closing the fifth control valve 341 and the eighth control valve 82, and opening the ninth control valve 344 and the fourth control valve 72, the gaseous fuel at the top of the fuel tank 3 is transported to the gasification unit 2.

[0109] While the present invention has been described with reference to several exemplary embodiments, it should be understood that the terms used are intended to be illustrative and exemplary rather than restrictive. Since the present invention can be embodied in many forms without departing from the spirit or essence of the invention, it should be understood that the above-described embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope of the appended claims. All changes and modifications that fall within the scope of the claims or their equivalents are intended to be covered by the appended claims.

Claims

1. A marine LNG fuel tank supply system, characterized in that: include: A filling unit, provided with a liquid phase filling port and a gas phase filling port; A gasification unit, used for gasifying the fuel, wherein the outlet of the gasification unit is connected to the engine; A fuel unit, the fuel unit comprising a fuel tank, the fuel tank being used to store fuel, the fuel tank being provided with a first liquid phase port and a gas phase port; a first manifold and a first control valve, wherein the first liquid-phase port and the liquid-phase filling port are connected via the first manifold so that the liquid in the filling unit can flow to the first liquid-phase port; and the first control valve is disposed on the first manifold and configured to control the conduction and cutoff of the first manifold; a second manifold and a second control valve, wherein the gas phase port and the gas phase filling port are connected via the second manifold, and the second control valve is provided on the second manifold and configured to control the conduction and cutoff of the second manifold; a third manifold and a third control valve, wherein the first liquid-phase port is connected to the inlet of the vaporization unit via the third manifold so that the liquid in the fuel tank can flow to the vaporization unit; and the third control valve is disposed on the third manifold and configured to control the conduction and cutoff of the third manifold; a fourth manifold and a fourth control valve, wherein the gas phase port is connected to the inlet of the gasification unit via the fourth manifold, and the fourth control valve is provided on the fourth manifold and configured to control the conduction and cutoff of the fourth manifold; a supercharger, wherein a liquid inlet end of the supercharger is connected to the first liquid-phase port through the third manifold to receive the fuel delivered by the fuel tank, and a gas outlet end of the supercharger is connected to the gas-phase port to deliver the gasified fuel of the supercharger to the fuel tank; an eighth control valve connected between the liquid inlet end of the supercharger and the third manifold, and configured to control conduction and cutoff between the liquid inlet end of the supercharger and the third manifold; a second pipeline and a ninth control valve, wherein the second pipeline is connected to the gas phase port, the second pipeline is connected to the second manifold and the fourth manifold, and the ninth control valve is provided on the second pipeline and is configured to control the conduction and cutoff of the second pipeline; There are at least two fuel tanks, and each of the fuel tanks can be filled with fuel through the filling unit and supply fuel to the gasification unit respectively.

2. The marine LNG fuel tank supply system according to claim 1, characterized in that: The fuel tank is further provided with a second liquid phase port, the liquid level of the second liquid phase port in the fuel tank being higher than that of the first liquid phase port; The second liquid-phase port is communicated with the liquid-phase filling port through the first manifold, so that the liquid in the filling unit can flow into the fuel tank.

3. The marine LNG fuel tank supply system according to claim 2, characterized in that: The fuel unit also includes a first pipeline, a first branch and a second branch. The first liquid phase port is connected to the first confluence pipeline and the third confluence pipeline through the first branch and the first pipeline. The second liquid phase port is connected to the first confluence pipe through the second branch and the first pipeline.

4. The marine LNG fuel tank supply system according to claim 3, characterized in that: The fuel unit comprises: a fifth control valve, provided on the first branch, and configured to control the conduction and cutoff of the first branch; a sixth control valve, provided on the second branch, and configured to control the conduction and cutoff of the second branch; The seventh control valve is provided on the first pipeline and is configured to control the conduction and cutoff of the first pipeline.

5. The marine LNG fuel tank supply system according to claim 1, characterized in that: The fuel unit further comprises: The third branch, the fuel tank is further provided with a fullness measuring port, the fullness measuring port is connected to the third branch; A temperature detector is provided on the third branch for detecting the pipe temperature of the third branch, and the first control valve can correspond to the temperature detector.

6. The marine LNG fuel tank supply system according to claim 1, characterized in that: The fuel unit further includes a pressure detector, which is provided on the fuel tank and is used to detect the pressure in the fuel tank. The eighth control valve is responsive to the pressure detector.

7. A control method for a marine LNG fuel tank supply system, characterized in that: The control method of the marine LNG fuel tank supply system is applied to the marine LNG fuel tank supply system according to any one of claims 1 to 6, wherein the marine LNG fuel tank supply system has a fuel filling mode and a fuel supply mode, and the control method includes: In the refueling mode, the liquid-phase refueling port is connected to the first liquid-phase port via the first manifold, the gas-phase refueling port is connected to the gas-phase port via the second manifold, and the third and fourth manifolds are blocked; In the fuel supply mode, the first liquid-phase port is connected to the inlet of the gasification unit through the third manifold, the gas-phase port is connected to the inlet of the gasification unit through the fourth manifold, and the first manifold and the second manifold are blocked.

8. The control method of the marine LNG fuel tank supply system according to claim 7, characterized in that: The marine LNG fuel tank supply system also includes a gaseous fuel supply mode, and the control method includes: In the gaseous fuel supply mode, the gaseous phase port is connected to the inlet of the gasification unit through the fourth manifold, and the first manifold, the second manifold and the third manifold are blocked.

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