Ammonia fuel supply and exhaust treatment system for a marine engine

Abstract

This invention discloses an ammonia fuel supply and exhaust gas treatment system for a marine engine. It includes multiple liquid ammonia storage tanks, a daily ammonia fuel tank, a first gas-liquid separator, and an exhaust gas treatment unit. The liquid ammonia storage tanks are connected to the daily ammonia fuel tanks, used to transfer stored liquid ammonia to the daily ammonia fuel tanks and receive liquid ammonia overflowing from the daily ammonia fuel tanks. The daily ammonia fuel tanks are also connected to the marine engine, used to transfer stored liquid ammonia to the marine engine. The marine engine is also connected to the first gas-liquid separator, used to transfer excess liquid ammonia to the first gas-liquid separator while consuming liquid ammonia. The first gas-liquid separator is also connected to both the daily ammonia fuel tanks and the exhaust gas treatment unit, used to perform gas-liquid separation on the received liquid ammonia, transferring the separated liquid ammonia to the daily ammonia fuel tanks and the separated ammonia exhaust gas to the exhaust gas treatment unit. The exhaust gas treatment unit is used to treat the ammonia exhaust gas. This system enables a safe and reliable supply of ammonia fuel and treatment of ammonia exhaust gas.

Description

Technical Field

[0001] This invention relates to the field of engine technology, and in particular to an ammonia fuel supply and exhaust gas treatment system for a marine engine. Background Technology

[0002] With the official implementation of the Tier III emission standard for ships on January 1, 2016, global emission requirements for ships have become increasingly stringent, especially in Europe and the United States. As a result, the development of various new dual-fuel engines has flourished. In recent years, dual-fuel marine engines such as low-pressure natural gas, high-pressure natural gas, LPG, methanol, dimethyl ether, liquid ammonia, and hydrogen fuel have been launched and developed.

[0003] WinGD and MAN, manufacturers of marine low-speed diesel engines, recently announced the successful development of ammonia-fueled low-speed diesel engines and the gradual rollout of commercial models. It is expected that commercial ammonia-fueled diesel engines will be officially launched in China in 2026-2027.

[0004] Although ammonia is classified as mildly hazardous in terms of toxicity, its highly volatile, flammable, and explosive properties mean that leaks can easily cause serious personal injury or death. Therefore, designing a safe and reliable fuel supply and exhaust gas system is of paramount importance and an urgent priority. Summary of the Invention

[0005] This invention provides an ammonia fuel supply and exhaust gas treatment system for marine engines to solve the problem of the lack of safe and reliable fuel supply and exhaust gas systems.

[0006] This invention provides an ammonia fuel supply and exhaust gas treatment system for a marine engine, characterized in that it includes multiple liquid ammonia storage tanks, a daily ammonia fuel tank, a first gas-liquid separator, and an exhaust gas treatment unit. The liquid ammonia storage tank is connected to the ammonia fuel daily use tank via a double-walled pipe, which is used to transfer the stored liquid ammonia to the ammonia fuel daily use tank, and also to receive liquid ammonia overflowing from the ammonia fuel daily use tank; The ammonia fuel tank is also connected to the marine engine via a double-walled pipe for transferring the stored liquid ammonia to the marine engine. The marine engine is also connected to the first gas-liquid separator tank, and is used to transfer excess liquid ammonia to the first gas-liquid separator tank while consuming the received liquid ammonia. The first gas-liquid separator is also connected to the ammonia fuel daily use tank and the waste gas treatment unit respectively, for gas-liquid separation of the received liquid ammonia, and for transferring the separated liquid ammonia to the ammonia fuel daily use tank and the separated ammonia waste gas to the waste gas treatment unit. The waste gas treatment unit is used to treat the ammonia waste gas.

[0007] Optionally, it also includes a liquid ammonia fuel supply unit and a compressor; The liquid ammonia fuel supply device injects liquid ammonia into the liquid ammonia storage tank through a delivery pipe; During the process of adding liquid ammonia, the ammonia gas generated by the volatilization of the liquid ammonia storage tank is pressurized by the compressor and then sent back to the liquid ammonia fuel supply device to balance the pressure.

[0008] Optionally, it may also include a first delivery pump and a first pneumatic valve; The inlet of the first delivery pump is connected to the outlet of the plurality of liquid ammonia storage tanks, and the outlet of the first delivery pump is connected to the inlet of the plurality of liquid ammonia storage tanks and the inlet of the ammonia fuel daily use tank. The first pneumatic valve is connected between the outlet of the first delivery pump and the inlet of the plurality of liquid ammonia storage tanks.

[0009] Optionally, a second gas-liquid separator may also be included; The double-walled tube includes an inner tube and an outer tube; the outer tube is sleeved on the outside of the inner tube, forming an annular gap between the outer wall of the inner tube and the inner wall of the outer tube. The inner pipe is connected between the liquid ammonia storage tank and the ammonia fuel daily use tank for transferring liquid ammonia; The lowest point of the outer pipe is provided with a discharge port; the discharge port is connected to the second gas-liquid separator, and the liquid ammonia leaking from the inner pipe is transferred to the second gas-liquid separator. The second gas-liquid separator is also connected to the liquid ammonia storage tank and the waste gas treatment unit, respectively, for gas-liquid separation of the received liquid ammonia, and for transferring the separated liquid ammonia to the liquid ammonia storage tank and the separated ammonia waste gas to the waste gas treatment unit.

[0010] Optionally, manual valves and pneumatic valves are also included; The manual valve and the pneumatic valve are connected in series at the discharge port.

[0011] Optional, a colorimetric bar may also be included; The color-developing bar is installed on the outer tube and is used to provide a color-based early warning when the inner tube leaks.

[0012] Optionally, the connection method between the color developing bar and the outer tube includes at least one of flange connection, threaded connection and clamp connection.

[0013] Optionally, the color developing bar is made of a transparent material; The transparent material includes at least one of plexiglass, tempered glass, polyethylene, and silicone.

[0014] Optionally, the colorimetric bar is provided with a porous material inside; The porous material is coated with a chemical color developer; The chemical colorimetric reagents include purple litmus, phenolphthalein, or indigo carmine.

[0015] Optionally, the ammonia waste gas is pressure regulated and then enters a water washing tower for washing. After the ammonia is removed by an activated carbon adsorption tank, it is discharged in compliance with standards. The ammonia water generated from the water washing is cooled in the first stage, neutralized with dilute hydrochloric acid, and cooled in the second stage to obtain an ammonium chloride solution. A portion of the ammonium chloride solution is returned to the water washing tower as washing liquid circulation according to a preset circulation ratio, and the other portion is treated as waste liquid for external discharge.

[0016] The technical solution of this invention, by adopting the above-mentioned ammonia fuel supply and waste gas treatment system including multiple liquid ammonia storage tanks, ammonia fuel daily use tanks, a first gas-liquid separator and a waste gas treatment unit, can not only achieve a safe and reliable supply of ammonia fuel, but also achieve ammonia waste gas treatment, thus solving the problem of lacking a safe and reliable fuel supply and waste gas system.

[0017] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A schematic diagram of an ammonia fuel supply and exhaust gas treatment system for a marine engine provided in an embodiment of the present invention; Figure 2 A schematic diagram of another ammonia fuel supply and exhaust gas treatment system for a marine engine provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of another ammonia fuel supply and exhaust gas treatment system for a marine engine provided in an embodiment of the present invention. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0021] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or device that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or devices. The terms "upper," "lower," "left," "right," etc., indicate orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings and are only used to describe the relative positional relationships between components or constituent parts, and do not specifically limit the specific installation orientation of each component or constituent part.

[0022] Figure 1 This is a schematic diagram of an ammonia fuel supply and exhaust gas treatment system for a marine engine provided in an embodiment of the present invention. (Refer to...) Figure 1 The ammonia fuel supply and exhaust gas treatment system for a marine engine 10' provided in this embodiment of the invention is characterized by comprising multiple liquid ammonia storage tanks 10, a daily ammonia fuel tank 20, a first gas-liquid separator 30, and an exhaust gas treatment unit 40; the liquid ammonia storage tanks 10 are connected to the daily ammonia fuel tank 20 via double-walled pipes, for transferring stored liquid ammonia to the daily ammonia fuel tank 20, and also for receiving liquid ammonia overflowing from the daily ammonia fuel tank 20; the daily ammonia fuel tank 20 is also connected to the marine engine 10' via double-walled pipes, for transferring stored liquid ammonia to the daily ammonia fuel tank 20. The marine engine 10' is also connected to the first gas-liquid separator 30, which is used to transfer excess liquid ammonia to the first gas-liquid separator 30 while consuming the received liquid ammonia; the first gas-liquid separator 30 is also connected to the ammonia fuel daily tank 20 and the exhaust gas treatment unit 40, respectively, for gas-liquid separation of the received liquid ammonia, and transferring the separated liquid ammonia to the ammonia fuel daily tank 20, and transferring the separated ammonia exhaust gas to the exhaust gas treatment unit 40; the exhaust gas treatment unit 40 is used to treat the ammonia exhaust gas.

[0023] It should be noted that the number of liquid ammonia storage tanks 10 is not limited in the embodiments of the present invention. The present invention is illustrated by taking two liquid ammonia storage tanks 10 as an example. Those skilled in the art can set the number according to actual conditions (such as the mileage of the ship).

[0024] After the marine engine 10' starts, the liquid ammonia storage tank 10 will transfer the stored liquid ammonia to the ammonia fuel day tank 20 through a double-walled pipe to ensure that the ammonia fuel day tank 20 can provide sufficient ammonia fuel for the engine. The liquid ammonia transfer between the liquid ammonia storage tank 10 and the ammonia fuel day tank 20, as well as between the ammonia fuel day tank 20 and the marine engine 10', all adopt double-walled pipe transfer, which is safer and conducive to achieving a safe and reliable supply of ammonia fuel.

[0025] It is understandable that when the marine engine 10' burns and consumes liquid ammonia, it will inevitably produce ammonia exhaust gas. Ammonia exhaust gas is hazardous. To avoid safety accidents, this embodiment of the invention includes a first gas-liquid separator 30 and an exhaust gas treatment unit 40. The first gas-liquid separator 30 can separate the ammonia exhaust gas from the liquid ammonia discharged from the engine. The exhaust gas treatment unit 40 can receive the ammonia exhaust gas separated and output from the first gas-liquid separator 30 and treat it to ensure that no ammonia exhaust gas leakage occurs. The ammonia-free liquid ammonia separated by the first gas-liquid separator 30 is then transported back to the ammonia fuel daily use tank 20, enabling the recycling of liquid ammonia and reducing energy waste.

[0026] The embodiments of the present invention employ the above-mentioned ammonia fuel supply and waste gas treatment system, which includes multiple liquid ammonia storage tanks 10, ammonia fuel daily use tanks 20, a first gas-liquid separator 30, and a waste gas treatment unit 40. This system not only enables a safe and reliable supply of ammonia fuel but also enables ammonia waste gas treatment, thus solving the problem of the lack of a safe and reliable fuel supply and waste gas system.

[0027] Figure 2 This is a schematic diagram of another ammonia fuel supply and exhaust gas treatment system for a marine engine provided in an embodiment of the present invention, with reference to... Figure 2 The ammonia fuel supply and exhaust gas treatment system in this embodiment of the invention also includes a liquid ammonia fuel supply device 50 and a compressor 60; the liquid ammonia fuel supply device 50 injects liquid ammonia into the liquid ammonia storage tank 10 through a delivery pipe; during the injection of liquid ammonia, the ammonia gas generated by the volatilization of the liquid ammonia storage tank 10 is pressurized by the compressor 60 and then transported back to the liquid ammonia fuel supply device 50 to balance the pressure.

[0028] It should be noted that the liquid ammonia fuel supply device 50 in the embodiments of the present invention can be a liquid ammonia tanker or a liquid ammonia refueling berth. The embodiments of the present invention are illustrated by taking the liquid ammonia fuel supply device 50 as a liquid ammonia tanker.

[0029] For example, 1.6 MPaG of liquid ammonia fuel from the tanker can be transported to the liquid ammonia storage tank 10 (which may have a storage pressure of 0.8 MPaG) via a delivery pipe (e.g., a hose in the refueling system). It is understood that during the process of transporting the liquid ammonia fuel from the tanker to the liquid ammonia storage tank 10 via the refueling system, the liquid ammonia in the storage tank 10 will evaporate to produce ammonia gas. To maintain system pressure balance and ensure continuous and stable refueling, the evaporated ammonia gas in the storage tank 10 can be pressurized by the compressor 60 and then returned to the gas phase space of the tanker. This achieves a closed-loop gas phase circulation and pressure balance, preventing overpressure in the liquid ammonia storage tank 10 and preventing ammonia leakage, thus ensuring the safe and smooth operation of the refueling process.

[0030] Figure 3 This is a schematic diagram of the structure of another ammonia fuel supply and exhaust gas treatment system for a marine engine provided in an embodiment of the present invention, with reference to... Figure 3 The ammonia fuel supply and exhaust gas treatment system in this embodiment of the invention further includes a first delivery pump 70 and a first pneumatic valve 80; the inlet of the first delivery pump 70 is connected to the outlet of a plurality of liquid ammonia storage tanks 10, and the outlet of the first delivery pump 70 is connected to the inlet of a plurality of liquid ammonia storage tanks 10 and the inlet of ammonia fuel daily use tank 20; the first pneumatic valve 80 is connected between the outlet of the first delivery pump 70 and the inlet of a plurality of liquid ammonia storage tanks 10.

[0031] For example, the first transfer pump 70 in this embodiment of the invention can be a low-pressure transfer pump. The low-pressure transfer pump can provide power for the transfer of liquid ammonia, stably transferring liquid ammonia from the liquid ammonia storage tank 10 to the ammonia fuel daily use tank 20, ensuring a continuous, stable, and reliable supply of liquid ammonia, and meeting the system flow and pressure requirements.

[0032] When the marine engine 10' starts, liquid ammonia fuel can be first transported to the first transfer pump 70 through a double-walled pipe. The first transfer pump 70 has two outlets, one of which is connected to the ammonia fuel daily tank 20 through a double-walled pipe; the other is connected to the inlet (e.g., the upper inlet) of the two liquid ammonia storage tanks 10 through pipelines. After the first pneumatic valve 80 connecting the outlet of the first transfer pump 70 and the inlet of the two liquid ammonia storage tanks 10 is opened, the pipeline connecting the outlet of the first transfer pump 70 and the inlet of the liquid ammonia storage tank 10 can be used for pump backflow to stabilize pressure, prevent pump cavitation and overpressure, realize mutual transfer between ammonia storage tanks, and also, in the event of a leak in a liquid ammonia storage tank 10, transfer the leaking liquid ammonia from the leaking liquid ammonia storage tank 10 to another liquid ammonia storage tank 10 for safety.

[0033] refer to Figure 3The ammonia fuel supply and exhaust gas treatment system in this embodiment of the invention also includes a second gas-liquid separator 90; the double-walled pipe includes an inner pipe and an outer pipe; the outer pipe is sleeved on the outside of the inner pipe, forming an annular gap between the outer wall of the inner pipe and the inner wall of the outer pipe; the inner pipe is connected between the liquid ammonia storage tank 10 and the ammonia fuel daily use tank 20 for transmitting liquid ammonia; a discharge port is provided at the lowest point of the outer pipe; the discharge port is connected to the second gas-liquid separator 90, and the liquid ammonia leaking from the inner pipe is transmitted to the second gas-liquid separator 90; the second gas-liquid separator 90 is also connected to the liquid ammonia storage tank 10 and the exhaust gas treatment unit 40 respectively, for gas-liquid separation of the received liquid ammonia, and transmitting the separated liquid ammonia to the liquid ammonia storage tank 10, and transmitting the separated ammonia exhaust gas to the exhaust gas treatment unit 40.

[0034] For example, since leakage of liquid ammonia in a sealed chamber can easily cause a major accident, in order to avoid such an accident, the liquid ammonia delivery pipe in this embodiment of the invention uses a double-walled pipe. When the inner pipe leaks, the outer pipe can collect the leaked liquid ammonia and can work in conjunction with the second gas-liquid separator 90 and the waste gas treatment unit 40 to treat the leaked liquid ammonia. Figure 3 In the illustrated embodiment, the pipelines between the liquid ammonia storage tank 10 and the ammonia fuel daily use tank 20, the pipelines between the ammonia fuel daily use tank 20 and the marine engine 10', the pipelines between the marine engine 10' and the first gas-liquid separator 30, and the pipelines between the first gas-liquid separator 30 and the ammonia fuel daily use tank 20 all use double-walled pipes. Discharge ports can be installed at the lowest point of the double-walled pipe sections and at the lowest point of the ammonia fuel daily use tank 20. Each discharge port can be connected to the central inlet of the second gas-liquid separator 90 via a collection pipe. Thus, in the event of a leak in the inner pipe of the double-walled pipe, the leak can be discharged to the second gas-liquid separator 90 through the emergency discharge port at the lowest point on the outer pipe. Figure 3 In the illustrated embodiment, a second transfer pump 200 is also installed between the bottom liquid phase outlet of the second gas-liquid separator 90 and the liquid ammonia storage tank 10. The bottom liquid phase outlet of the second gas-liquid separator 90 can be connected to the inlet of the second transfer pump 200 via a pipeline, and the outlet of the second transfer pump 200 is connected to the top inlets of the two liquid ammonia storage tanks 10 via pipelines respectively. This allows the ammonia-free liquid separated from the second gas-liquid separator 90 to be transported back to the liquid ammonia storage tank 10, enabling the recycling of liquid ammonia and reducing energy waste. The top gas phase outlet of the second gas-liquid separator 90 can be connected to the waste gas treatment unit 40 via a pipeline, allowing the ammonia waste gas separated from the second gas-liquid separator 90 to be transferred to the waste gas treatment unit 40 for treatment, preventing ammonia waste gas leakage and accidents.

[0035] refer to Figure 3 The ammonia fuel supply and exhaust gas treatment system in this embodiment of the invention also includes a manual valve 100 and a second pneumatic valve 110; the manual valve 100 and the second pneumatic valve 110 are connected in series at the discharge port.

[0036] The present invention provides a double seal by setting a manual valve 100 and a second pneumatic valve 110 arranged in series at the discharge port, which can avoid the leakage of liquid ammonia due to the failure of a single valve and meet the high safety requirements of ammonia fuel supply.

[0037] refer to Figure 3 The ammonia fuel supply and exhaust gas treatment system in this embodiment of the invention also includes a color indicator bar 120; the color indicator bar 120 is installed on the outer pipe and is used to provide a color warning when the inner pipe leaks.

[0038] For example, a reasonable number of color-developing rods 120 can be installed on the outer tube of the double-walled pipe as needed for daily inspection. If the inner tube of the double-walled pipe leaks, the chemical color-developing agent built into the color-developing rod 120 closest to the leak point will react with liquid ammonia and change color, thus helping staff to determine the location of the pipe leak. In a feasible embodiment, the color-developing rod 120 in this embodiment of the invention has a porous material inside; the porous material is coated with a chemical color-developing agent; the chemical color-developing agent includes purple litmus, phenolphthalein, or indigo carmine.

[0039] For example, purple litmus turns blue when it comes into contact with liquid ammonia, phenolphthalein turns red when it comes into contact with liquid ammonia, and indigo carmine turns green when it comes into contact with liquid ammonia.

[0040] Optionally, the connection method between the color developing bar 120 and the outer tube in the embodiments of the present invention includes at least one of flange connection, threaded connection and clamp connection.

[0041] It should be noted that the connection method between the colorimetric bar 120 and the outer tube is not limited in the embodiments of the present invention, and those skilled in the art can set it themselves.

[0042] Optionally, the colorimetric bar 120 in this embodiment of the invention is made of a transparent material; the transparent material includes at least one of plexiglass, tempered glass, polyethylene, and silicone.

[0043] By making the color developing rod 120 transparent, this embodiment of the invention allows on-site personnel to quickly and remotely identify color changes in the chemical color developing agent within the rod, thereby enabling timely assessment of any potential leaks of liquid ammonia and improving operational safety.

[0044] refer to Figure 3 In this embodiment of the invention, the ammonia waste gas is washed in the water washing tower 41 after pressure regulation, and then the ammonia gas is removed by the activated carbon adsorption tank 42 before being discharged in compliance with standards. The ammonia water generated by water washing is cooled in the first stage, neutralized with dilute hydrochloric acid, and cooled in the second stage to obtain ammonium chloride solution. A portion of the ammonium chloride solution is returned to the water washing tower 41 as washing liquid circulation according to a preset circulation ratio, and the other portion is discharged as waste liquid.

[0045] exist Figure 3 In the embodiment shown, the waste gas treatment unit 40 of the present invention includes a water washing tower 41, an activated carbon adsorption tank 42, a primary cooler 43, a mixing reactor 44, a secondary cooler 45, and a third transfer pump 46.

[0046] Specifically, ammonia waste gas from the first gas-liquid separator 30 and the second gas-liquid separator 90 is transported to the waste gas treatment unit 40 via pipeline. It first enters the lower gas phase inlet of the water scrubbing tower 41. After countercurrent contact with the circulating solution (e.g., ammonium chloride solution) from the middle of the water scrubbing tower 41 and fresh fresh water from the top of the water scrubbing tower 41, most of the ammonia waste gas is dissolved and flows to the bottom of the tower. A small amount of residual waste gas containing ammonia is discharged through the top outlet and transported to the activated carbon adsorption tank 42. The ammonia waste gas is further adsorbed by the activated carbon, and the harmless unadsorbed gas is discharged into the atmosphere through the outlet, meeting emission standards. The ammonia water at the bottom of the water scrubbing tower 41, due to the exothermic dissolution, needs to be cooled by the primary cooler 43 and circulating cooling water. The cooled ammonia water is then transported to the mixing reactor 44 to neutralize with a hydrochloric acid solution (e.g., 15wt% dilute hydrochloric acid solution). The resulting ammonium chloride solution, due to the exothermic reaction, undergoes cascade cooling by the secondary cooler 45 and the circulating cooling water discharged from the primary cooler 43. After final cooling, part of the ammonium chloride solution is circulated as a solvent to the ammonia scrubbing tower 41 via the third transfer pump 46 to wash the ammonia gas, while the other part is discharged from the system for external treatment. The use of a circulating solvent can significantly reduce the consumption of precious freshwater resources by the scrubbing tower 41. By using ammonium chloride as a circulating solvent and employing a circulating water cascade cooling process, the exhaust gas treatment unit 40 can significantly reduce the consumption of freshwater and circulating water, which is conducive to achieving the goal of energy saving and consumption reduction in the system, while also reducing the complexity of the system.

[0047] This invention employs a combined waste gas treatment process of water washing, neutralization, and adsorption to ensure that the waste gas meets emission standards. It should be noted that the three processes of water washing, neutralization, and adsorption can be freely combined and are not limited to a specific combination.

[0048] refer to Figure 3 Optionally, some of the ammonia gas volatilized in the liquid ammonia storage tank 10 in this embodiment of the invention can also enter the waste gas treatment unit 40 for treatment. The treatment process is the same as the ammonia waste gas treatment process output from the first gas-liquid separator 30 and the second gas-liquid separator 90, and will not be described in detail here.

[0049] refer to Figure 3 Optionally, the ammonia fuel supply and exhaust gas treatment system in this embodiment of the invention further includes a fourth transfer pump 130, a heat exchanger 140, and a liquid supply valve group 150 disposed between the ammonia fuel daily tank 20 and the marine engine 10'.

[0050] For example, the fourth delivery pump 130 can be a high-pressure delivery pump, which can pressurize liquid ammonia to provide the engine with high-pressure, stable ammonia fuel with the required flow rate, ensuring that the fuel can be smoothly injected into the cylinder to participate in combustion and meet the pressure requirements for normal engine operation. Specifically, the outlet of the ammonia fuel tank 20 is connected to the inlet of the fourth delivery pump 130 through a double-walled pipe. The liquid ammonia output from the ammonia fuel tank 20 is pressurized to the pressure required by the engine by the fourth delivery pump 130 and then delivered to the cold side inlet of the heat exchanger 140 through the double-walled pipe. After heat exchange with the circulating ethylene glycol solution, the ammonia fuel is connected to the liquid supply valve group 150 through the double-walled pipe. After pressure regulation and flow stabilization, it is then connected to the engine fuel inlet through the double-walled pipe.

[0051] refer to Figure 3 Optionally, the ammonia fuel supply and exhaust gas treatment system in this embodiment of the invention further includes a return valve group 160 and a first pressure regulating valve 170 disposed between the marine engine 10' and the first gas-liquid separator 30.

[0052] Specifically, after the marine engine 10' draws in the required ammonia fuel, the excess ammonia fuel is first transported to the return valve group 160 through the return port of the marine engine 10', and then, after being regulated by the first pressure regulating valve 170, it is transported to the first gas-liquid separator 30 through the double-walled pipe.

[0053] refer to Figure 3 Optionally, the ammonia fuel supply and exhaust gas treatment system in this embodiment of the invention further includes a fifth delivery pump 180 disposed between the first gas-liquid separator 30 and the ammonia fuel daily use tank 20, and a second pressure regulating valve 190 connected between the first gas-liquid separator 30 and the water washing tower 41.

[0054] For example, the liquid ammonia separated by the first gas-liquid separator 30 first exits from the bottom outlet of the first gas-liquid separator 30, and then is transported to the inlet of the fifth transfer pump 180 through a double-walled pipe. The outlet of the fifth transfer pump 180 is connected to the upper inlet of the ammonia fuel daily use tank 20 through the double-walled pipe, which can transport liquid ammonia fuel to the ammonia fuel daily use tank 20. The ammonia gas separated by the first gas-liquid separator 30 first exits from the upper outlet of the first gas-liquid separator 30, and then is connected to the second pressure regulating valve 190 through a pipeline. After being pressure regulated by the second pressure regulating valve 190, it is then transported to the bottom gas phase inlet of the water washing tower 41 through a pipeline.

[0055] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. An ammonia fuel supply and exhaust gas treatment system for a marine engine, characterized in that, It includes multiple liquid ammonia storage tanks, ammonia fuel daily use tanks, a first gas-liquid separator, and a waste gas treatment unit; The liquid ammonia storage tank is connected to the ammonia fuel daily use tank via a double-walled pipe, which is used to transfer the stored liquid ammonia to the ammonia fuel daily use tank, and also to receive liquid ammonia overflowing from the ammonia fuel daily use tank; The ammonia fuel tank is also connected to the marine engine via a double-walled pipe for transferring the stored liquid ammonia to the marine engine. The marine engine is also connected to the first gas-liquid separator tank, and is used to transfer excess liquid ammonia to the first gas-liquid separator tank while consuming the received liquid ammonia. The first gas-liquid separator is also connected to the ammonia fuel daily use tank and the waste gas treatment unit respectively, for gas-liquid separation of the received liquid ammonia, and for transferring the separated liquid ammonia to the ammonia fuel daily use tank and the separated ammonia waste gas to the waste gas treatment unit. The waste gas treatment unit is used to treat the ammonia waste gas.

2. The ammonia fuel supply and exhaust gas treatment system according to claim 1, characterized in that, It also includes a liquid ammonia fuel supply unit and a compressor; The liquid ammonia fuel supply device injects liquid ammonia into the liquid ammonia storage tank through a delivery pipe; During the process of adding liquid ammonia, the ammonia gas generated by the volatilization of the liquid ammonia storage tank is pressurized by the compressor and then sent back to the liquid ammonia fuel supply device to balance the pressure.

3. The ammonia fuel supply and waste gas treatment system according to claim 1, characterized in that, It also includes a first delivery pump and a first pneumatic valve; The inlet of the first delivery pump is connected to the outlet of the plurality of liquid ammonia storage tanks, and the outlet of the first delivery pump is connected to the inlet of the plurality of liquid ammonia storage tanks and the inlet of the ammonia fuel daily use tank. The first pneumatic valve is connected between the outlet of the first delivery pump and the inlet of the plurality of liquid ammonia storage tanks.

4. The ammonia fuel supply and waste gas treatment system according to claim 1, characterized in that, It also includes a second gas-liquid separator; The double-walled tube includes an inner tube and an outer tube; the outer tube is sleeved on the outside of the inner tube, forming an annular gap between the outer wall of the inner tube and the inner wall of the outer tube. The inner pipe is connected between the liquid ammonia storage tank and the ammonia fuel daily use tank for transferring liquid ammonia; The lowest point of the outer pipe is provided with a discharge port; the discharge port is connected to the second gas-liquid separator, and the liquid ammonia leaking from the inner pipe is transferred to the second gas-liquid separator. The second gas-liquid separator is also connected to the liquid ammonia storage tank and the waste gas treatment unit, respectively, for gas-liquid separation of the received liquid ammonia, and for transferring the separated liquid ammonia to the liquid ammonia storage tank and the separated ammonia waste gas to the waste gas treatment unit.

5. The ammonia fuel supply and exhaust gas treatment system according to claim 4, characterized in that, It also includes a manual valve and a second pneumatic valve; The manual valve and the second pneumatic valve are connected in series at the discharge port.

6. The ammonia fuel supply and exhaust gas treatment system according to claim 4, characterized in that, It also includes color developing bars; The color-developing bar is installed on the outer tube and is used to provide a color-based early warning when the inner tube leaks.

7. The ammonia fuel supply and exhaust gas treatment system according to claim 6, characterized in that, The connection method between the colorimetric bar and the outer tube includes at least one of flange connection, threaded connection and clamp connection.

8. The ammonia fuel supply and exhaust gas treatment system according to claim 6, characterized in that, The color developing bar is made of a transparent material; The transparent material includes at least one of plexiglass, tempered glass, polyethylene, and silicone.

9. The ammonia fuel supply and exhaust gas treatment system according to claim 6, characterized in that, The colorimetric bar contains a porous material. The porous material is coated with a chemical color developer; The chemical colorimetric reagents include purple litmus, phenolphthalein, or indigo carmine.

10. The ammonia fuel supply and exhaust gas treatment system according to claim 1, characterized in that, After pressure regulation, the ammonia waste gas enters the water washing tower for washing, and then the ammonia gas is removed by the activated carbon adsorption tank before being discharged in compliance with standards. The ammonia water generated by the water washing is cooled in the first stage, neutralized with dilute hydrochloric acid, and cooled in the second stage to obtain an ammonium chloride solution. A portion of the ammonium chloride solution is returned to the water washing tower as washing liquid circulation according to a preset circulation ratio, and the other portion is treated as waste liquid for external discharge.

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