Ammonia fuel supply system

Abstract

The invention discloses an ammonia fuel supply system, and belongs to the technical field of ship environmental protection. The ammonia fuel supply system comprises a fuel enclosure unit, and further comprises a filling unit, a fuel supply unit and a fuel supply unit, wherein the filling unit is communicated with the fuel enclosure unit through a filling pipeline; the fuel enclosure unit is communicated with the ammonia fuel machine through the fuel treatment unit; the purification unit is communicated with each unit gas phase release interface of the ammonia fuel supply system; the gas return pipeline is arranged between the storage tank and the filling unit, and in the filling process, the gas phase part in the storage tank can return to the filling unit through the gas return pipeline, so that the pressure of the storage tank is kept stable, and the filling amount is guaranteed. In the sailing process, the pressure in the storage tank can be kept stable through the first pressure stabilizing unit. In order to improve the use safety, the recovery tank, the gas phase treatment unit and the ventilation unit are communicated through a pipeline to treat escaped and released gas, and the treated gas meeting related emission requirements is exhausted to the atmosphere through the tail end of the system, so that the environment is prevented from being damaged.

Description

Technical Field

[0001] The invention relates to the technical field of ship environmental protection, and in particular to an ammonia fuel supply system. Background Art

[0002] As the international community continues to strengthen its requirements for carbon emission control, it has become inevitable for the shipping industry to choose new low-carbon or carbon-free fuels. Ammonia (NH3) does not produce greenhouse gas carbon dioxide when burned, and its production process is mature and relatively easy to store and transport. Therefore, there is great potential for ships to use ammonia as fuel.

[0003] Ammonia is a combustible hydrogen-rich compound that contains no carbon and sulfur. It produces water and nitrogen when completely burned, but does not produce pollutants or the greenhouse gas carbon dioxide (CO2). It has a high hydrogen content and a higher volume energy density than liquid hydrogen. The raw materials for its production contain nitrogen and hydrogen. Compared with other green and clean fuels, the future production cost will be the lowest. It is a clean and efficient energy alternative.

[0004] Ammonia is gaseous under normal temperature and pressure difference, and is toxic and corrosive. Therefore, the treatment of ammonia needs to be considered during the storage, transportation and use of liquid ammonia. The existing ammonia fuel supply system does not have good recycling measures for the ammonia generated by volatilization in the liquid tank. If the ammonia released from the pipeline is directly discharged without treatment, it will also pose a threat to human life and environmental pollution. Summary of the invention

[0005] The purpose of the present invention is to solve the problem that in the prior art, an ammonia fuel engine selects liquid ammonia as a second fuel, while meeting the temperature, pressure, cleanliness and related requirements of the liquid ammonia fuel at the inlet of the ammonia fuel engine, and at the same time solves the problem that there is no better utilization measure for the evaporated gas in the liquid ammonia storage tank in the prior art, and the gas escaping and released in the pipeline and process container is directly discharged into the atmosphere, which may pose a threat to human life and environmental pollution, and proposes an ammonia fuel supply system.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: An ammonia fuel supply system includes a fuel containment unit, and further includes: a filling unit, the filling unit is connected to the fuel containment unit through a filling pipeline, a return air pipeline is fixedly provided on the fuel containment unit, and the end of the return air pipeline away from the fuel containment unit is connected to the filling unit, and a first pressure stabilizing unit is provided on the fuel containment unit; an ammonia fuel engine, the fuel containment unit is connected to the ammonia fuel engine through a fuel processing unit; and a purification unit, the purification unit is connected to the gas phase release interface of each unit of the ammonia fuel supply system.

[0007] Preferably, a gas phase pipeline and a liquid phase pipeline are fixedly arranged on the first pressure stabilizing unit, the gas phase pipeline is connected with the return air pipeline, and the liquid phase pipeline is connected with the filling pipeline.

[0008] Preferably, the fuel processing unit includes: a first filter unit, which is connected to the inside of the fuel enclosure unit through a fuel delivery unit; a fuel boost supply unit, wherein a first heat exchange unit and a second heat exchange unit are fixedly arranged at both ends of the fuel boost supply unit, the output end of the first filter unit is connected to the input end of the first heat exchange unit, and a second filter unit is fixedly arranged at the output end of the second heat exchange unit, and the second filter unit is connected to the input end of the ammonia fuel engine through a valve group unit.

[0009] Furthermore, a liquid collecting tank is fixedly arranged between the fuel pressure boost supply unit and the first heat exchange unit, a bypass pipeline is fixedly arranged between the fuel pressure boost supply unit and the second heat exchange unit, the bypass pipeline is connected to the liquid collecting tank, and a regulating valve is fixedly arranged on the bypass pipeline.

[0010] Furthermore, the purification unit includes a second voltage stabilizing unit, a recovery tank is fixedly provided at the input end of the second voltage stabilizing unit, a gas phase treatment unit is fixedly provided at the output end of the second voltage stabilizing unit, a ventilation unit is fixedly provided at the output end of the gas phase treatment unit, and the other end of the ammonia fuel engine is connected to the recovery tank.

[0011] Furthermore, an ammonia liquid pipeline and an ammonia fuel engine return pipeline are fixedly arranged on the recovery tank, respectively; the ammonia liquid pipeline and the ammonia fuel engine return pipeline are both connected to the liquid collecting tank; valves are fixedly arranged on the ammonia liquid pipeline and the ammonia fuel engine return pipeline; and the other end of the ammonia fuel engine is connected to the ammonia fuel engine return pipeline.

[0012] Compared with the prior art, the present invention provides an ammonia fuel supply system, which has the following beneficial effects: 1. The ammonia fuel supply system sets a return air pipeline between the storage tank and the filling unit. During the filling process, the gas phase in the storage tank can return to the filling unit through the return air pipeline to maintain the stability of the storage tank pressure and ensure the filling volume. During navigation, the first pressure stabilizing unit can be used to maintain the stability of the pressure in the storage tank to avoid the rupture of the overpressure structure of the fuel containment unit, thereby posing a threat to the ship, the marine environment and the safety of personnel; 2. The ammonia fuel supply system connects the recovery tank, the second pressure stabilizing unit, the gas phase treatment unit and the ventilation unit in sequence through pipelines. The ammonia separated from the second pressure stabilizing unit is treated by the gas phase treatment unit. The gas that meets the relevant emission requirements after treatment is discharged into the atmosphere through the ventilation unit, thereby avoiding damage to the environment.

[0013] The parts not involved in the device are the same as the prior art or can be implemented by using the prior art. The present invention provides an air return pipeline between the fuel containment unit and the filling unit. The ammonia in the fuel containment unit can return to the filling unit through the air return pipeline, thereby reducing volatilization and leakage and improving safety in use. The recovery tank, the second pressure stabilizing unit, the gas phase treatment unit and the breathable unit are connected in sequence through pipelines, and the ammonia separated from the second pressure stabilizing unit is treated by the gas phase treatment unit. The gas that meets the relevant emission requirements after treatment is discharged into the atmosphere through the breathable unit, thereby avoiding damage to the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A schematic diagram of an ammonia fuel supply system proposed by the present invention; Figure 2 Schematic diagram of an expansion of an ammonia fuel supply system proposed by the present invention Figure 1 ; Figure 3 Schematic diagram of an expansion of an ammonia fuel supply system proposed by the present invention Figure 2 .

[0015] In the figure: 1. filling unit; 2. fuel containment unit; 3. fuel delivery unit; 4. first pressure stabilizing unit; 5. first filtering unit; 6. first heat exchange unit; 7. fuel boost supply unit; 8. second heat exchange unit; 9. second filtering unit; 10. valve group unit; 11. ammonia fuel engine; 12. recovery tank; 13. second pressure stabilizing unit; 14. gas phase treatment unit; 15. ventilation unit; 16. filling pipeline; 17. return air pipeline; 18. gas phase pipeline; 19. liquid phase pipeline; 20. ammonia liquid pipeline; 21. bypass pipeline; 22. regulating valve; 23. liquid collecting tank. DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0017] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0018] Embodiment 1: Reference Figure 1, an ammonia fuel supply system, including a fuel containment unit 2, and also includes: a filling unit 1, the filling unit 1 is connected to the fuel containment unit 2 through a filling pipeline 16, a return air pipeline 17 is fixedly provided on the fuel containment unit 2, and the end of the return air pipeline 17 away from the fuel containment unit 2 is connected to the filling unit 1, and a first voltage stabilizing unit 4 is provided on the fuel containment unit 2; an ammonia fuel engine 11, the fuel containment unit 2 is connected to the ammonia fuel engine 11 through a fuel processing unit; a purification unit, the purification unit is connected to the gas phase release interface of each unit of the ammonia fuel supply system, that is, the purification unit is connected to the exhaust gas discharge end of each unit of the system, and is used to treat the generated exhaust gas. When in use, the recovery tank, the second voltage stabilizing unit 13, the gas phase processing unit and the ventilation unit are connected by a pipeline to treat the escaped and released gas. The gas that meets the relevant emission requirements after treatment is discharged to the atmosphere through the end of the system, thereby avoiding threatening human life safety and damaging the environment. During the filling operation, liquid ammonia is filled into the liquid ammonia fuel containment unit 2 through the filling pipeline 16. The lowest temperature of the liquid ammonia in the liquid ammonia filling pipeline 16 can reach -34 degrees Celsius, the filling pressure does not exceed 10 bar, and the filling rate does not exceed 3 m / s; the ammonia generated in the fuel containment unit 2 is returned to the filling unit 1 through the return air pipeline 17, which can reduce volatilization and leakage and improve safety of use.

[0019] Reference Figure 1 A gas phase pipeline 18 and a liquid phase pipeline 19 are fixedly arranged on the first pressure stabilizing unit 4. The first pressure stabilizing unit 4 can select a pressure storage tank, a reliquefaction system, a supercooling system, an oxidation system, an absorption system, and a decomposition system, and select one or more processing methods to maintain the pressure in the fuel containment unit 2 stable. The gas phase pipeline 18 is connected with the return air pipeline 17, and the liquid phase pipeline 19 is connected with the filling pipeline 16. When the ship is running, a pressure gauge is arranged in the fuel containment unit 2 to monitor the pressure in the containment unit in real time. When the pressure in the fuel containment unit 2 rises to a critical value, the ammonia in the fuel containment unit 2 is sent to the first pressure stabilizing unit 4 for treatment through the gas phase pipeline 18. The ammonia after compression and cooling treatment is liquefied and then sent back to the fuel containment unit 2 through the liquid phase pipeline 19, thereby reducing the pressure in the fuel containment unit 2 to avoid safety hazards.

[0020] Reference Figure 1The fuel processing unit includes: a first filter unit 5, which is connected to the fuel containment unit 2 through a fuel delivery unit 3; a fuel boost supply unit 7, wherein a first heat exchange unit 6 and a second heat exchange unit 8 are fixedly arranged at both ends of the fuel boost supply unit 7, an output end of the first filter unit 5 is connected to an input end of the first heat exchange unit 6, and a second filter unit 9 is fixedly arranged at an output end of the second heat exchange unit 8, and the second filter unit 9 is connected to an input end of an ammonia fuel machine 11 through a valve group unit 10, a liquid collecting tank 23 is fixedly arranged between the fuel boost supply unit 7 and the first heat exchange unit 6, and the liquid collecting tank 23 mixes the liquid ammonia refluxed from the ammonia fuel machine 11 with the liquid ammonia delivered from the fuel containment unit 2 and then supplies the fuel to the fuel boost supply unit 7, a bypass pipeline 21 is fixedly arranged between the fuel boost supply unit 7 and the second heat exchange unit 8, the bypass pipeline 21 is connected to the liquid collecting tank 23, and the bypass pipeline 2 1 is fixedly provided with a regulating valve 22, which is used to adjust the ammonia fuel flow supplied to the marine ammonia fuel ammonia fuel engine 11 according to the actual operating load demand of the ammonia fuel engine 11. When the ship is running, the liquid ammonia in the fuel containment unit 2 is pressurized to the inlet requirement of the fuel pressurization supply unit 7 by the fuel delivery unit 3, and then transported to the inlet of the first filtering unit 5. The filtered liquid ammonia enters the fuel pressurization supply unit 7, and is pressurized to the required pressure at the inlet of the ammonia fuel engine 11, and then transported to the inlet of the second heat exchange unit 8. The liquid ammonia is heated by the second heat exchange unit 8 and heated to the required temperature at the inlet of the ammonia fuel engine 11, and then transported to the ammonia fuel engine 11 after passing through the valve group unit 10. Furthermore, a first heat exchange unit 6 is provided at the outlet of the first filtering unit 5, which can pre-exchange the liquid ammonia entering the fuel pressurization supply unit 7. Similarly, a second filter unit 9 is provided at the outlet of the second heat exchange unit 8, which can further filter.

[0021] Reference Figure 1 The purification unit includes a second voltage stabilizing unit 13, a recovery tank 12 is fixedly provided at the input end of the second voltage stabilizing unit 13, a gas phase treatment unit 14 is fixedly provided at the output end of the second voltage stabilizing unit 13, a ventilation unit 15 is fixedly provided at the output end of the gas phase treatment unit 14, and the other end of the ammonia fuel engine 11 is connected to the recovery tank 12.

[0022] Reference Figure 1, an ammonia liquid pipeline 20 and an ammonia fuel engine return pipeline are fixedly provided on the recovery tank 12, and both the ammonia liquid pipeline 20 and the ammonia fuel engine return pipeline are connected to the liquid collecting tank 23, and valves are fixedly provided on the ammonia liquid pipeline 20 and the ammonia fuel engine return pipeline, and the other end of the ammonia fuel engine 11 is connected to the ammonia fuel engine return pipeline, and there are two groups of valves on the ammonia fuel engine return pipeline, which are respectively located at the two ends of the connection between the ammonia fuel engine 11 and the ammonia fuel engine return pipeline. The recovery tank 12 ensures that the pressure in the tank is maintained at not less than the inlet required pressure of the fuel boost supply unit 7 by filling nitrogen, and is connected to the liquid collecting tank 23 through the ammonia liquid pipeline 20 to ensure that the pressure in the ammonia liquid supply main pipeline maintains the inlet required pressure of the fuel boost supply unit 7. The mixed gas of nitrogen and ammonia at the top of the recovery tank 12 is sent to the downstream gas phase treatment unit 14 after passing through the recovery tank 13, and the ammonia concentration is ensured not to exceed 25ppm and then discharged to the atmosphere through the ventilation unit 15.

[0023] Embodiment 2: Reference Figure 2 , which is basically the same as the first embodiment. On the basis of the first embodiment, we add a liquid collecting tank 23 to serve as a buffer tank. The two groups of liquid collecting tanks 23 are respectively at the two ends of the fuel boost supply unit 7. The setting of the buffer tank solves the problem of large fuel flow fluctuations generated when the fuel boost supply unit 7 adopts a volumetric pump.

[0024] Embodiment three: Reference Figure 3 , which is basically the same as the first embodiment. On the basis of the first embodiment, we have made an optimization and set a second filter unit 9 on the pipeline between the collecting tank 23 and the inlet of the fuel boost supply unit 7. This arrangement can not only reduce the impurity content of the ammonia fuel entering the fuel boost supply unit 7, thereby avoiding the fuel boost supply unit 7 from not being able to work normally or even being damaged due to the fuel entering the fuel boost supply unit 7 containing more impurities, but also reduce the use of components and improve the use effect.

[0025] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An ammonia fuel supply system, comprising a fuel containment unit (2), characterized in that: Also includes: A filling unit (1), the filling unit (1) being connected to the inside of a fuel containment unit (2) via a filling pipeline (16), a return air pipeline (17) being fixedly provided on the fuel containment unit (2), and an end of the return air pipeline (17) away from the fuel containment unit (2) being connected to the filling unit (1), and a first pressure stabilizing unit (4) being provided on the fuel containment unit (2); An ammonia fuel engine (11), wherein the fuel containment unit (2) is connected to the ammonia fuel engine (11) via a fuel processing unit; A purification unit is connected to the gas phase release interfaces of each unit of the ammonia fuel supply system.

2. An ammonia fuel supply system according to claim 1, characterized in that: A gas phase pipeline (18) and a liquid phase pipeline (19) are fixedly arranged on the first pressure stabilizing unit (4); the gas phase pipeline (18) is connected to the gas return pipeline (17), and the liquid phase pipeline (19) is connected to the filling pipeline (16).

3. An ammonia fuel supply system according to claim 1, characterized in that: The fuel processing unit comprises: A first filter unit (5), the first filter unit (5) being connected to the fuel containment unit (2) via the fuel delivery unit (3); A fuel boost supply unit (7), wherein a first heat exchange unit (6) and a second heat exchange unit (8) are fixedly arranged at both ends of the fuel boost supply unit (7), the output end of the first filter unit (5) is connected to the input end of the first heat exchange unit (6), and the output end of the second heat exchange unit (8) is fixedly arranged with a second filter unit (9), and the second filter unit (9) is connected to the input end of an ammonia fuel engine (11) via a valve group unit (10).

4. An ammonia fuel supply system according to claim 3, characterized in that: A liquid collecting tank (23) is fixedly arranged between the fuel pressure boosting supply unit (7) and the first heat exchange unit (6), a bypass pipeline (21) is fixedly arranged between the fuel pressure boosting supply unit (7) and the second heat exchange unit (8), the bypass pipeline (21) is connected to the liquid collecting tank (23), and a regulating valve (22) is fixedly arranged on the bypass pipeline (21).

5. An ammonia fuel supply system according to claim 4, characterized in that: The purification unit comprises a second voltage stabilizing unit (13), a recovery tank (12) is fixedly arranged at the input end of the second voltage stabilizing unit (13), a gas phase treatment unit (14) is fixedly arranged at the output end of the second voltage stabilizing unit (13), a permeability unit (15) is fixedly arranged at the output end of the gas phase treatment unit (14), and the other end of the ammonia fuel engine (11) is connected to the recovery tank (12).

6. An ammonia fuel supply system according to claim 5, characterized in that: An ammonia liquid pipeline (20) and an ammonia fuel engine return pipeline are fixedly arranged on the recovery tank (12), respectively; the ammonia liquid pipeline (20) and the ammonia fuel engine return pipeline are both connected to the liquid collecting tank (23); valves are fixedly arranged on the ammonia liquid pipeline (20) and the ammonia fuel engine return pipeline; and the other end of the ammonia fuel engine (11) is connected to the ammonia fuel engine return pipeline.

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