A combined heat and power system and control method for a ship's methanol engine and fuel cell

Abstract

This invention relates to a combined heat and power (CHP) system and control method for a marine methanol engine and fuel cell. The system comprises: a marine methanol engine, a second three-way valve, a radiator, a first three-way valve, a second temperature sensor, a circulating water pump, an expansion tank, a heat exchanger, a first temperature sensor, a fuel cell reactor, a storage tank, a hydrogen purification device, a catalytic reformer, and a methanol storage tank. This invention uses cooling water from the marine methanol engine to insulate the circulating water in the fuel cell reactor, improving the stability of the fuel cell's operating temperature and power output. It also uses exhaust gas from the marine methanol engine to heat the methanol catalytic reforming hydrogen production reaction, thus solving the problem of hydrogen transport difficulties while saving energy and reducing economic costs.

Description

Technical Field

[0001] This invention relates to the field of marine methanol engine technology, and is a combined heat and power system and control method for a marine methanol engine and fuel cell. Background Technology

[0002] Over the past decade, research on the use of methanol as a hydrogen energy carrier in ship main engines has increased, showing significant advantages in reducing harmful gas emissions. Compared with marine fuel oil, its emission reduction effect and environmental performance are very significant.

[0003] Hydrogen is a clean energy source. Fuel cells using hydrogen as a raw material have advantages such as high energy conversion rate, low noise, and zero emissions. They can also reduce ship vibration and noise, providing a good working and living environment for crew members.

[0004] Operating temperature significantly impacts the durability, economics, and environmental adaptability of fuel cell systems. Currently, the main method for controlling fuel cell operating temperature involves establishing a comprehensive temperature control system with both internal and external circulation loops, encompassing both heating and insulation states. However, each initial activation of the external circulation loop causes a sharp drop in the temperature at the fuel cell reactor water inlet, reducing the system's efficiency. The cooling water temperature of marine methanol engines is 70-80°C, decreasing to 40-50°C after passing through the radiator. In contrast, the operating temperature of low-temperature proton exchange membrane hydrogen-oxygen fuel cells is 60-80°C. This provides an opportunity to utilize the cooling water from marine methanol engines to maintain the fuel cell's operating temperature.

[0005] Hydrogen storage on ships is difficult; however, the methanol fuel required by marine methanol engines can serve as a hydrogen storage carrier, saving space. The temperature for producing hydrogen through methanol steam catalytic reforming is 200-350℃, while the exhaust gas temperature of marine methanol engines can reach 250-400℃, making it a suitable heat source for the methanol catalytic reforming reaction. How to rationally utilize the cooling water and waste heat from marine methanol engines to improve the overall system's energy efficiency and the working efficiency of each piece of equipment is a pressing issue that needs to be addressed. Summary of the Invention

[0006] To address the shortcomings of existing technologies, and in order to utilize the cooling water of a marine methanol engine to control the temperature of the circulating water in a cryogenic proton exchange membrane hydrogen-oxygen fuel cell reactor, and to use the waste heat from the exhaust gas of the marine methanol engine to provide heat for the methanol catalytic reforming hydrogen production reaction, this invention provides a combined heat and power system and control method for a marine methanol engine and fuel cell.

[0007] This invention provides the following technical solutions:

[0008] A combined heat and power system for a marine methanol engine and fuel cell, the system comprising: a marine methanol engine, a second three-way valve, a radiator, a first three-way valve, a second temperature sensor, a circulating water pump, an expansion tank, a heat exchanger, a first temperature sensor, a fuel cell reactor, a storage tank, a hydrogen purification device, a catalytic reformer, and a methanol storage tank.

[0009] The cooling water outlet of the marine methanol engine, the radiator, the first three-way valve and the second three-way valve are connected. The first three-way valve is connected to the heat exchanger. The heat exchanger is connected to the radiator. The radiator is connected to the marine methanol engine. After the cooling water flows out of the marine methanol engine, it passes through the second three-way valve and the first three-way valve and then enters the heat exchanger.

[0010] The fuel cell reactor is connected to a heat exchanger, which is connected to a circulating water pump, which is connected to an expansion tank, and the circulating water pump is connected to the fuel cell reactor. The circulating water from the fuel cell reactor flows out of the outlet, exchanges heat with the cooling water in the heat exchanger, and then flows back to the fuel cell reactor.

[0011] The exhaust outlet of the marine methanol engine is connected to the catalytic reformer, the methanol storage tank is connected to the catalytic reformer, water vapor is introduced into the catalytic reformer, the outlet of the catalytic reformer is connected to the inlet of the hydrogen purification equipment, the outlet of the hydrogen purification equipment is connected to the inlet of the hydrogen storage tank, and the outlet of the hydrogen storage tank is connected to the air inlet of the fuel cell reactor.

[0012] The first temperature sensor measures the outlet temperature of the fuel cell reactor circulating water, and the second temperature sensor measures the inlet temperature of the fuel cell reactor circulating water.

[0013] Preferably, methanol enters the catalytic reformer from the methanol storage tank and undergoes a catalytic reforming reaction with water vapor under the heating of the exhaust gas from the marine methanol engine to produce hydrogen. The hydrogen is then stored in the storage tank and then enters the fuel cell reactor for electrochemical reaction.

[0014] Preferably, the heat exchanger includes plates, a hot inlet manifold, a cold inlet manifold, a hot outlet manifold, and a cold outlet manifold. Cooling water enters from the hot inlet manifold, and circulating water enters from the cold inlet manifold. Heat exchange occurs between the spaced plates. Afterward, the cooling water flows out from the hot outlet manifold, and the circulating water flows out from the cold outlet manifold. The cooling water then returns to the marine methanol engine after being cooled by the radiator.

[0015] Preferably, when the circulating water volume of the fuel cell reactor is insufficient, the expansion tank supplies water to the circulating water circuit through a circulating pump.

[0016] A method for controlling cogeneration of a methanol engine and fuel cell in a ship, the method comprising the following steps:

[0017] After the cooling water of the marine methanol engine comes out of the cooling water outlet, it passes through the first three-way valve and the second three-way valve into the hot inlet manifold at the top of the heat exchanger and flows from top to bottom. The circulating water of the fuel cell reactor enters the cold inlet manifold at the bottom of the heat exchanger and flows from bottom to top. The hot and cold baffles are connected at intervals to fully convect heat exchange. After that, they enter the outlet manifold and then flow out.

[0018] The first temperature sensor measures the outlet temperature of the circulating water in the fuel cell reactor, and the second temperature sensor measures the inlet temperature of the circulating water in the fuel cell reactor. When the fuel cell is operating, if the first temperature sensor in the circulating water circuit senses that the temperature of the circulating water is lower than a first temperature value, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase until it is fully open. If the second temperature sensor senses that the temperature of the circulating water is lower than the first temperature value, it controls the opening of the second three-way valve at the heat exchanger end to gradually increase. If the first temperature sensor senses that the temperature of the circulating water is higher than the first temperature value but lower than the second temperature value, it controls the opening of the first three-way valve at the radiator end to gradually increase. If the first temperature sensor senses that the temperature of the circulating water is higher than a second set value, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase until it is fully open. If the second temperature sensor senses that the temperature of the circulating water is higher than the second set value, it controls the opening of the second three-way valve at the radiator end to gradually increase until the temperature of the second temperature sensor stabilizes near the second set value.

[0019] Preferably, when the first temperature sensor detects that the temperature of the circulating water is below 20°C, the opening of the first three-way valve at the heat exchanger end is gradually increased to full opening by a change of 5%. When the second temperature sensor detects that the temperature of the circulating water is below 30°C, the opening of the second three-way valve at the radiator inlet end is controlled to be 0.

[0020] Preferably, when the circulating water temperature sensed by the first temperature sensor is higher than 20°C and lower than 45°C, the opening of the first three-way valve at the heat exchanger end is gradually reduced by a change of 2%. When the circulating water temperature sensed by the second temperature sensor is higher than 30°C and lower than 55°C, the opening of the second three-way valve at the radiator end is gradually increased by a change of 2%.

[0021] When the first temperature sensor detects that the temperature of the circulating water is higher than 45°C, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase by 3%. When the second temperature sensor detects that the temperature of the circulating water is higher than 55°C, it controls the opening of the second three-way valve at the radiator end to gradually increase by 5%.

[0022] Preferably, by adjusting the cooling water flow rate and volume in the cooling water circuit, the cooling water from the ship's methanol engine is used to gradually increase the circulating water temperature of the fuel cell reactor during the process from start-up to normal operation, and then stabilize it at the operating temperature of the fuel cell. This improves the efficiency of the combined heat and power system and reduces greenhouse gas emissions and energy consumption.

[0023] A computer-readable storage medium having a computer program stored thereon, which is executed by a processor to implement a cogeneration control method for a marine methanol engine and fuel cell.

[0024] A computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement a cogeneration control method for a marine methanol engine and fuel cell.

[0025] The present invention has the following beneficial effects:

[0026] Compared with the prior art, the present invention:

[0027] This invention uses cooling water from a marine methanol engine to insulate the circulating water in a fuel cell reactor, improving the stability of the fuel cell's operating temperature and power output. It also uses exhaust gas from the marine methanol engine to heat the methanol catalytic reforming hydrogen production reaction, solving the problem of hydrogen transport difficulties while saving energy and reducing economic costs. This invention maintains a stable fuel cell operating temperature without requiring additional heating devices. Attached Figure Description

[0028] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the structure of the present invention;

[0030] Figure 2 This is a schematic diagram of a heat exchanger.

[0031] In the diagram, 1-Marine methanol engine, 2-Second three-way valve, 3-Radiator, 4-First three-way valve, 5-Second temperature sensor, 6-Circulating water pump, 7-Expansion tank, 8-Heat exchanger, 9-First temperature sensor, 10-Fuel cell reactor, 11-Storage tank, 12-Hydrogen purification equipment, 13-Catalytic reformer, 14-Methanol storage tank, 15-Plate, 16-Hot inlet manifold, 17-Cold inlet manifold, 18-Hot outlet manifold, 19-Cold outlet manifold. Detailed Implementation

[0032] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0034] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0035] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0036] The present invention will be described in detail below with reference to specific embodiments. Specific Implementation Example 1:

[0038] according to Figures 1-2 As shown, the specific optimized technical solution adopted by the present invention to solve the above-mentioned technical problems is: The present invention relates to a combined heat and power system and control method for a ship's methanol engine and fuel cell.

[0039] This invention provides a combined heat and power system for a marine methanol engine and fuel cell, the system comprising: a marine methanol engine 1, a second three-way valve 2, a radiator 3, a first three-way valve 4, a second temperature sensor 5, a circulating water pump 6, an expansion tank 7, a heat exchanger 8, a first temperature sensor 9, a fuel cell reactor 10, a storage tank 11, a hydrogen purification device 12, a catalytic reformer 13, and a methanol storage tank 14.

[0040] The cooling water outlet of the marine methanol engine 1, the radiator 3, the first three-way valve 4 and the second three-way valve 2 are connected. The first three-way valve 4 is connected to the heat exchanger 8. The heat exchanger 8 is connected to the radiator 3. The radiator 3 is connected to the marine methanol engine 1. After the cooling water flows out of the marine methanol engine 1, it passes through the second three-way valve 2 and the first three-way valve 4 and then enters the heat exchanger 8.

[0041] The fuel cell reactor 10 is connected to the heat exchanger 8, the heat exchanger 8 is connected to the circulating water pump 6, the circulating water pump 6 is connected to the expansion tank 7, and the circulating water pump 6 is connected to the fuel cell reactor 10. After the circulating water of the fuel cell reactor 10 flows out from the outlet, it exchanges heat with the cooling water in the heat exchanger 8 and then flows back to the fuel cell reactor 10.

[0042] The exhaust outlet of the marine methanol engine 1 is connected to the catalytic reformer 13, the methanol storage tank 14 is connected to the catalytic reformer 13, water vapor is introduced into the catalytic reformer 13, the outlet of the catalytic reformer 13 is connected to the inlet of the hydrogen purification equipment 12, the outlet of the hydrogen purification equipment 12 is connected to the inlet of the hydrogen storage tank 11, and the outlet of the hydrogen storage tank 11 is connected to the air inlet of the fuel cell reactor 10.

[0043] The first temperature sensor 9 measures the outlet temperature of the circulating water in the fuel cell reactor 10, and the second temperature sensor 5 measures the inlet temperature of the circulating water in the fuel cell reactor 10. Specific Implementation Example 2:

[0045] The difference between Embodiment 2 and Embodiment 1 of the present invention lies only in:

[0046] Methanol enters the catalytic reformer from the methanol storage tank and undergoes a catalytic reforming reaction with water vapor under the heat of the exhaust gas from the marine methanol engine to produce hydrogen. The hydrogen is then stored in the storage tank and then enters the fuel cell reactor for electrochemical reaction. Specific Implementation Example 3:

[0048] The difference between Embodiment 3 and Embodiment 2 of the present invention lies only in:

[0049] The heat exchanger includes plates, a hot inlet manifold, a cold inlet manifold, a hot outlet manifold, and a cold outlet manifold. Cooling water enters through the hot inlet manifold, and circulating water enters through the cold inlet manifold. Heat exchange occurs between the plates. Afterward, the cooling water flows out through the hot outlet manifold, and the circulating water flows out through the cold outlet manifold. The cooling water then returns to the marine methanol engine after being cooled by the radiator. Specific Implementation Example 4:

[0051] The only difference between Embodiment 4 and Embodiment 3 of the present invention is that:

[0052] When the circulating water volume of the fuel cell reactor is insufficient, the expansion tank supplies water to the circulating water circuit through the circulation pump. Specific Implementation Example 5:

[0054] The difference between Embodiment 5 and Embodiment 4 of the present invention lies only in:

[0055] This invention provides a method for controlling cogeneration of a ship's methanol engine and fuel cell, the method comprising the following steps:

[0056] After the cooling water of the marine methanol engine comes out of the cooling water outlet, it passes through the first three-way valve and the second three-way valve into the hot inlet manifold at the top of the heat exchanger and flows from top to bottom. The circulating water of the fuel cell reactor enters the cold inlet manifold at the bottom of the heat exchanger and flows from bottom to top. The hot and cold baffles are connected at intervals to fully convect heat exchange. After that, they enter the outlet manifold and then flow out.

[0057] The first temperature sensor measures the outlet temperature of the circulating water in the fuel cell reactor, and the second temperature sensor measures the inlet temperature of the circulating water in the fuel cell reactor. When the fuel cell is operating, if the first temperature sensor in the circulating water circuit senses that the temperature of the circulating water is lower than a first temperature value, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase until it is fully open. If the second temperature sensor senses that the temperature of the circulating water is lower than the first temperature value, it controls the opening of the second three-way valve at the heat exchanger end to gradually increase. If the first temperature sensor senses that the temperature of the circulating water is higher than the first temperature value but lower than the second temperature value, it controls the opening of the first three-way valve at the radiator end to gradually increase. If the first temperature sensor senses that the temperature of the circulating water is higher than a second set value, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase until it is fully open. If the second temperature sensor senses that the temperature of the circulating water is higher than the second set value, it controls the opening of the second three-way valve at the radiator end to gradually increase until the temperature of the second temperature sensor stabilizes near the second set value. Specific Implementation Example Six:

[0059] The difference between Embodiment Six and Embodiment Five of the present invention lies only in:

[0060] When the first temperature sensor detects that the temperature of the circulating water is below 20°C, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase to full opening in increments of 5%. When the second temperature sensor detects that the temperature of the circulating water is below 30°C, it controls the opening of the second three-way valve at the radiator end to be 0. Specific Implementation Example 7:

[0062] The difference between Embodiment Seven and Embodiment Six of the present invention lies only in:

[0063] When the circulating water temperature sensed by the first temperature sensor is higher than 20℃ and lower than 45℃, the opening of the first three-way valve at the heat exchanger end is gradually reduced by 2%. When the circulating water temperature sensed by the second temperature sensor is higher than 30℃ and lower than 55℃, the opening of the second three-way valve at the radiator end is gradually increased by 2%.

[0064] When the first temperature sensor detects that the temperature of the circulating water is higher than 45°C, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase by 3%. When the second temperature sensor detects that the temperature of the circulating water is higher than 55°C, it controls the opening of the second three-way valve at the radiator end to gradually increase by 5%. Specific Implementation Example 8:

[0066] The difference between Embodiment 8 and Embodiment 7 of the present invention lies only in:

[0067] By adjusting the flow rate and volume of cooling water in the cooling water circuit, the cooling water of the ship's methanol engine is used to gradually increase the temperature of the circulating water in the fuel cell reactor from startup to normal operation, and then stabilize it at the operating temperature of the fuel cell. This improves the efficiency of the combined heat and power system and reduces greenhouse gas emissions and energy consumption. Specific Implementation Example Nine:

[0069] The difference between Embodiment Nine and Embodiment Eight of the present invention lies only in:

[0070] The present invention provides a computer-readable storage medium having a computer program stored thereon, which is executed by a processor to implement a cogeneration control method for a marine methanol engine and fuel cell.

[0071] The method includes the following steps:

[0072] After the cooling water of the marine methanol engine comes out of the cooling water outlet, it passes through the first three-way valve and the second three-way valve into the hot inlet manifold at the top of the heat exchanger and flows from top to bottom. The circulating water of the fuel cell reactor enters the cold inlet manifold at the bottom of the heat exchanger and flows from bottom to top. The hot and cold baffles are connected at intervals to fully convect heat exchange. After that, they enter the outlet manifold and then flow out.

[0073] The first temperature sensor measures the outlet temperature of the circulating water in the fuel cell reactor, and the second temperature sensor measures the inlet temperature of the circulating water in the fuel cell reactor. When the fuel cell is operating, if the first temperature sensor in the circulating water circuit senses that the temperature of the circulating water is lower than a first temperature value, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase until it is fully open. If the second temperature sensor senses that the temperature of the circulating water is lower than the first temperature value, it controls the opening of the second three-way valve at the heat exchanger end to gradually increase. If the first temperature sensor senses that the temperature of the circulating water is higher than the first temperature value but lower than the second temperature value, it controls the opening of the first three-way valve at the radiator end to gradually increase. If the first temperature sensor senses that the temperature of the circulating water is higher than a second set value, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase until it is fully open. If the second temperature sensor senses that the temperature of the circulating water is higher than the second set value, it controls the opening of the second three-way valve at the radiator end to gradually increase until the temperature of the second temperature sensor stabilizes near the second set value. Specific Implementation Example 10:

[0075] The only difference between Embodiment 10 and Embodiment 9 of the present invention is that:

[0076] The present invention provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement a cogeneration control method for a ship's methanol engine and fuel cell.

[0077] The method includes the following steps:

[0078] After the cooling water of the marine methanol engine comes out of the cooling water outlet, it passes through the first three-way valve and the second three-way valve into the hot inlet manifold at the top of the heat exchanger and flows from top to bottom. The circulating water of the fuel cell reactor enters the cold inlet manifold at the bottom of the heat exchanger and flows from bottom to top. The hot and cold baffles are connected at intervals to fully convect heat exchange. After that, they enter the outlet manifold and then flow out.

[0079] The first temperature sensor measures the outlet temperature of the circulating water in the fuel cell reactor, and the second temperature sensor measures the inlet temperature of the circulating water in the fuel cell reactor. When the fuel cell is operating, if the first temperature sensor in the circulating water circuit senses that the temperature of the circulating water is lower than a first temperature value, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase until it is fully open. If the second temperature sensor senses that the temperature of the circulating water is lower than the first temperature value, it controls the opening of the second three-way valve at the heat exchanger end to gradually increase. If the first temperature sensor senses that the temperature of the circulating water is higher than the first temperature value but lower than the second temperature value, it controls the opening of the first three-way valve at the radiator end to gradually increase. If the first temperature sensor senses that the temperature of the circulating water is higher than a second set value, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase until it is fully open. If the second temperature sensor senses that the temperature of the circulating water is higher than the second set value, it controls the opening of the second three-way valve at the radiator end to gradually increase until the temperature of the second temperature sensor stabilizes near the second set value. Specific Implementation Example Eleven:

[0081] The only difference between Embodiment Eleven and Embodiment Ten of this invention is that:

[0082] Combination Figure 1 This invention relates to a combined heat and power (CHP) system and control method for marine methanol engines and fuel cells, comprising four parts: a cooling water circuit, a circulating water circuit, a hydrogen flow circuit, and a control circuit. The cooling water circuit includes a marine methanol engine 1, a second three-way valve 2, a first three-way valve 4, a heat exchanger 8, and a radiator 3. The marine methanol engine cooling water outlet 1, the radiator outlet 3, the first three-way valve 4, and the second three-way valve 2 are connected. The first three-way valve 4 is connected to the heat exchanger 8, the heat exchanger 8 is connected to the radiator 3, and the radiator 3 is connected to the marine methanol engine 1. Cooling water flows out of the marine methanol engine 1, passes through the second three-way valve 2 and the first three-way valve 4, and then enters the heat exchanger 8.

[0083] The heat exchanger 8 includes plates 15, a hot inlet manifold 16, a cold inlet manifold 19, a hot outlet manifold 18, and a cold outlet manifold 17. Cooling water enters the heat exchanger 8 through the hot inlet manifold 16, and circulating water enters through the cold inlet manifold 19. Heat exchange occurs in the spaced plates 15. Afterward, the cooling water flows out through the hot outlet manifold 18, and the circulating water flows out through the cold outlet manifold 17. The cooling water then returns to the marine methanol engine after being cooled by the radiator 3.

[0084] The circulating water circuit includes a fuel cell reactor 10, a heat exchanger 8, a circulating water pump 6, and an expansion tank 7. The fuel cell reactor 10 is connected to the heat exchanger 8, the heat exchanger 8 is connected to the circulating water pump 6, the circulating water pump 6 is connected to the expansion tank 7, and the circulating water pump 6 is connected to the fuel cell reactor 10. The circulating water from the fuel cell reactor 10 flows out from the outlet, exchanges heat with the cooling water in the heat exchanger 8, and then flows back to the fuel cell reactor 10. When the circulating water volume of the fuel cell reactor 10 is insufficient, the expansion tank 7 supplies water to the circulating water circuit through the circulating pump 6. The hydrogen flow circuit includes a marine methanol engine 1, a methanol storage tank 14, a catalytic reformer 13, a hydrogen purification device 12, a hydrogen storage tank 11, and the fuel cell reactor 10. The exhaust outlet 1 of the marine methanol engine is connected to the catalytic reformer 13, and the methanol storage tank 14 is also connected to the catalytic reformer 13. Steam is introduced into the catalytic reformer 13. The outlet 13 of the catalytic reformer is connected to the inlet 12 of a hydrogen purification device, which in turn is connected to the inlet 11 of a hydrogen storage tank. The outlet 11 of the hydrogen storage tank is connected to the inlet 10 of the fuel cell reactor. Methanol enters the catalytic reformer 13 from the methanol storage tank 14 and undergoes a catalytic reforming reaction with steam under the heating of the exhaust gas from the marine methanol engine 1 to produce hydrogen. The hydrogen is then stored in the storage tank 11 and subsequently enters the fuel cell reactor 10 for an electrochemical reaction.

[0085] In the control circuit, the first temperature sensor 9 measures the outlet temperature of the circulating water in the fuel cell reactor 10, and the second temperature sensor 5 measures the inlet temperature of the circulating water in the fuel cell reactor 10. When the first temperature sensor 9 senses that the circulating water temperature is below 20°C, it controls the opening of the first three-way valve 4 at the heat exchanger 8 to gradually increase to full open in increments of 5%. When the second temperature sensor 5 senses that the circulating water temperature is below 30°C, it controls the opening of the second three-way valve 2 at the radiator 3 to be 0. When the first temperature sensor 9 senses that the circulating water temperature is above 20°C but below 45°C, it controls the opening of the first three-way valve 4 at the heat exchanger 6 to gradually decrease in increments of 2%. When the second temperature sensor 5 senses that the circulating water temperature is above 30°C but below 55°C, it controls the opening of the second three-way valve 2 at the radiator 3 to gradually increase in increments of 2%. The first temperature sensor 9 detects that the circulating water temperature is higher than 45°C, and controls the opening of the first three-way valve 4 at the heat exchanger end to gradually increase by 3%. The second temperature sensor 5 detects that the circulating water temperature is higher than 55°C, and controls the opening of the second three-way valve 2 at the radiator 3 end to gradually increase by 5%. This regulates the flow rate and volume of the cooling water in the cooling water circuit, thereby utilizing the cooling water of the ship's methanol engine 1 to achieve a gradual increase and then stabilization of the circulating water temperature in the fuel cell reactor 10 at the fuel cell's operating temperature during the process from start-up to normal operation. This improves the efficiency of the combined heat and power system and reduces greenhouse gas emissions and energy consumption.

[0086] The working principle of this invention is as follows: Cooling water flows out of the marine methanol engine 1, passes through the second three-way valve 2 and the first three-way valve 4, and then enters the heat exchanger 8. In the heat exchanger 8, it exchanges heat with the circulating water of the fuel cell reactor 10. After being cooled by the radiator 3, it returns to the marine methanol engine. The heat exchanger 8 includes plates 15, a hot inlet manifold 16, a cold inlet manifold 19, a hot outlet manifold 18, and a cold outlet manifold 17. Cooling water enters the heat exchanger 8 through the hot inlet manifold 16, and circulating water enters through the cold inlet manifold 19. Heat exchange occurs in the spaced plates 15. Cooling water then flows out through the hot outlet manifold 18, and circulating water flows out through the cold outlet manifold 17. Finally, the cooling water is cooled by the radiator 3 and returns to the marine methanol engine. The circulating water from the fuel cell reactor 10 flows out from the outlet, exchanges heat with cooling water in the heat exchanger 8, and then flows back to the fuel cell reactor 10. When the circulating water volume in the fuel cell reactor 10 is insufficient, the expansion tank 7 supplies water to the circulating water circuit through the circulation pump 6. Methanol enters the catalytic reformer 13 from the methanol storage tank 14 and undergoes catalytic reforming with water vapor under the heat of the exhaust gas from the marine methanol engine 1 to produce hydrogen. The hydrogen then enters the storage tank 11 for storage and then enters the fuel cell reactor 10 for electrochemical reaction. The first temperature sensor 9 measures the outlet temperature of the circulating water in the fuel cell reactor 10, and the second temperature sensor 5 measures the inlet temperature of the circulating water in the fuel cell reactor 10. The first temperature sensor 9 controls the opening of the first three-way valve 4 through a control signal, and the second temperature sensor 5 controls the opening of the second three-way valve 2. When the first temperature sensor 9 detects that the circulating water temperature is below 20℃, it controls the opening of the first three-way valve 4 at the heat exchanger 8 to gradually increase it to full open in increments of 5%. When the second temperature sensor 5 detects that the circulating water temperature is below 30℃, it controls the opening of the second three-way valve 2 at the radiator 3 to be 0. When the first temperature sensor 9 detects that the circulating water temperature is above 20℃ but below 45℃, it controls the opening of the first three-way valve 4 at the heat exchanger 6 to gradually decrease it in increments of 2%. When the second temperature sensor 5 detects that the circulating water temperature is above 30℃ but below 55℃, it controls the opening of the second three-way valve 2 at the radiator 3 to gradually increase it in increments of 2%. When the first temperature sensor 9 detects that the circulating water temperature is above 45℃, it controls the opening of the first three-way valve 4 at the heat exchanger to gradually increase it in increments of 3%. When the second temperature sensor 5 detects that the circulating water temperature is above 55℃, it controls the opening of the second three-way valve 2 at the radiator 3 to gradually increase it in increments of 5%. This regulates the flow rate and volume of cooling water in the cooling water circuit, so that the circulating water temperature of the fuel cell reactor 10 gradually increases and then stabilizes at the operating temperature of the fuel cell during the process from startup to normal operation.

[0087] The present invention, when applied to a combined heat and power system for a marine methanol engine and fuel cell, may further include:

[0088] The fuel cell is a low-temperature proton exchange membrane hydrogen-oxygen fuel cell. The external circulating water circuit of the fuel cell reactor controls the operating temperature of the fuel cell. The heat exchanger is a plate heat exchanger, including plates and two fluid channels, cold and hot. The cold and hot heat exchange media flow through their respective channels and exchange heat with the plates separated by them.

[0089] A first temperature sensor is connected to the outlet of the fuel cell reactor circulating water, and a second temperature sensor is connected to the inlet of the fuel cell reactor circulating water. The first temperature sensor is connected to a first three-way valve, and the second temperature sensor is connected to a second three-way valve.

[0090] The expansion tank replenishes the circulating water circuit when the circulating water level in the fuel cell reactor is insufficient. The catalytic reformer is connected to the steam inlet line. The circulating water pump is used to supply circulating water to the fuel cell reactor.

[0091] The fuel cell reactor is connected to an oxygen inlet pipe and an exhaust pipe to discharge the gas remaining after the electrochemical reaction in the fuel cell reactor.

[0092] Methanol storage tanks provide feedstock for marine methanol engines and catalytic reformers.

[0093] This invention relates to a control method for cogeneration of methanol engines and fuel cells in ships. Its key features are: cooling water from the marine methanol engine exits through a first three-way valve and a second three-way valve, then flows downwards into the upper heat inlet manifold of the heat exchanger; circulating water from the fuel cell reactor enters the lower cold inlet manifold of the heat exchanger, flowing upwards; hot and cold baffles are connected at intervals, ensuring sufficient convective heat exchange; and then both flow out through their respective outlet manifolds. A first temperature sensor measures the outlet temperature of the fuel cell reactor circulating water, and a second temperature sensor measures the inlet temperature of the fuel cell reactor circulating water. When the fuel cell is operating, when the first temperature sensor in the circulating water circuit senses that the temperature of the circulating water is lower than a first temperature value, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase until it is fully open. When the second temperature sensor senses that the temperature of the circulating water is lower than the first temperature value, it controls the opening of the second three-way valve at the heat exchanger end to gradually increase. When the first temperature sensor senses that the temperature of the circulating water is higher than the first temperature value but lower than the second temperature value, it controls the opening of the first three-way valve at the heat exchanger end to gradually decrease. When the second temperature sensor senses that the temperature of the circulating water is higher than the first temperature value but lower than the second temperature value, it controls the opening of the second three-way valve at the radiator end to gradually increase. When the first temperature sensor senses that the temperature of the circulating water is higher than a second set value, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase until it is fully open. When the second temperature sensor senses that the temperature of the circulating water is higher than the second set value, it controls the opening of the second three-way valve at the radiator end to gradually increase until the temperature of the second temperature sensor stabilizes near the second set value.

[0094] The cogeneration control method of the present invention applied to marine methanol engines and fuel cells may further include:

[0095] 1. When the fuel cell is first started, the first temperature sensor detects that the temperature of the circulating water is below 20°C and the temperature of the second temperature sensor is below 30°C. The opening of the first three-way valve at the heat exchanger end is gradually increased to full opening in increments of 5%, and the opening of the second three-way valve at the radiator end is controlled to be 0.

[0096] 2. When the fuel cell has started up, and the circulating water temperature sensed by the first temperature sensor is higher than 20℃ but lower than 45℃, and the circulating water temperature sensed by the second temperature sensor is higher than 30℃ but lower than 55℃, the opening of the first three-way valve at the heat exchanger end is gradually reduced by 2%, and the opening of the second three-way valve at the radiator end is gradually increased by 2%.

[0097] 3. When the fuel cell is operating normally, the first temperature sensor detects that the temperature of the circulating water is higher than 45°C, and the second temperature sensor detects that the temperature of the circulating water is higher than 55°C. The opening of the first three-way valve at the heat exchanger end is gradually increased by 3%, and the opening of the second three-way valve at the radiator end is gradually increased by 5%.

[0098] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or N embodiments or examples. Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of the present invention, "N" means at least two, such as two, three, etc., unless otherwise explicitly specified. Any process or method described in the flowcharts or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more N executable instructions for implementing custom logical functions or processes, and the scope of preferred embodiments of the invention includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order according to the functions involved, as will be understood by those skilled in the art to which embodiments of the invention pertain. The logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection having one or N wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic device, and portable optical disc read-only memory (CDROM).Furthermore, the computer-readable medium can even be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory. It should be understood that various parts of the invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0099] The above description is merely a preferred embodiment of a combined heat and power (CHP) system and control method for a marine methanol engine and fuel cell. The scope of protection for such a system and method is not limited to the above embodiments; all technical solutions falling within this conceptual framework are within the scope of protection of this invention. It should be noted that for those skilled in the art, any improvements and variations made without departing from the principles of this invention should also be considered within the scope of protection of this invention.

Claims

1. A combined heat and power system for a marine methanol engine and fuel cell, characterized in that: The system includes: a marine methanol engine, a second three-way valve, a radiator, a first three-way valve, a second temperature sensor, a circulating water pump, an expansion tank, a heat exchanger, a first temperature sensor, a fuel cell reactor, a storage tank, a hydrogen purification device, a catalytic reformer, and a methanol storage tank. The cooling water outlet of the marine methanol engine, the radiator, the first three-way valve and the second three-way valve are connected. The first three-way valve is connected to the heat exchanger. The heat exchanger is connected to the radiator. The radiator is connected to the marine methanol engine. After the cooling water flows out of the marine methanol engine, it passes through the second three-way valve and the first three-way valve and then enters the heat exchanger. The fuel cell reactor is connected to a heat exchanger, which is connected to a circulating water pump, which is connected to an expansion tank, and the circulating water pump is connected to the fuel cell reactor. The circulating water from the fuel cell reactor flows out of the outlet, exchanges heat with the cooling water in the heat exchanger, and then flows back to the fuel cell reactor. The exhaust outlet of the marine methanol engine is connected to the catalytic reformer, the methanol storage tank is connected to the catalytic reformer, water vapor is introduced into the catalytic reformer, the outlet of the catalytic reformer is connected to the inlet of the hydrogen purification equipment, the outlet of the hydrogen purification equipment is connected to the inlet of the hydrogen storage tank, and the outlet of the hydrogen storage tank is connected to the air inlet of the fuel cell reactor. The first temperature sensor measures the outlet temperature of the fuel cell reactor circulating water, and the second temperature sensor measures the inlet temperature of the fuel cell reactor circulating water.

2. The system according to claim 1, characterized in that: Methanol enters the catalytic reformer from the methanol storage tank and undergoes a catalytic reforming reaction with water vapor under the heat of the exhaust gas from the marine methanol engine to produce hydrogen. The hydrogen is then stored in the storage tank and then enters the fuel cell reactor for electrochemical reaction.

3. The system according to claim 2, characterized in that: The heat exchanger includes plates, a hot inlet manifold, a cold inlet manifold, a hot outlet manifold, and a cold outlet manifold. Cooling water enters through the hot inlet manifold, and circulating water enters through the cold inlet manifold. Heat exchange occurs between the plates. Afterward, the cooling water flows out through the hot outlet manifold, and the circulating water flows out through the cold outlet manifold. The cooling water then returns to the marine methanol engine after being cooled by the radiator.

4. The system according to claim 3, characterized in that: When the circulating water volume of the fuel cell reactor is insufficient, the expansion tank supplies water to the circulating water circuit through the circulation pump.

5. A method for controlling cogeneration of a ship's methanol engine and fuel cell, characterized in that: The method includes the following steps: After the cooling water of the marine methanol engine comes out of the cooling water outlet, it passes through the first three-way valve and the second three-way valve into the hot inlet manifold at the top of the heat exchanger and flows from top to bottom. The circulating water of the fuel cell reactor enters the cold inlet manifold at the bottom of the heat exchanger and flows from bottom to top. The hot and cold baffles are connected at intervals to fully convect heat exchange. After that, they enter the outlet manifold and then flow out. The first temperature sensor measures the outlet temperature of the circulating water in the fuel cell reactor, and the second temperature sensor measures the inlet temperature of the circulating water in the fuel cell reactor. When the fuel cell is operating, if the first temperature sensor in the circulating water circuit senses that the temperature of the circulating water is lower than a first temperature value, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase until it is fully open. If the second temperature sensor senses that the temperature of the circulating water is lower than the first temperature value, it controls the opening of the second three-way valve at the heat exchanger end to gradually increase. If the first temperature sensor senses that the temperature of the circulating water is higher than the first temperature value but lower than the second temperature value, it controls the opening of the first three-way valve at the radiator end to gradually increase. If the first temperature sensor senses that the temperature of the circulating water is higher than a second set value, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase until it is fully open. If the second temperature sensor senses that the temperature of the circulating water is higher than the second set value, it controls the opening of the second three-way valve at the radiator end to gradually increase until the temperature of the second temperature sensor stabilizes near the second set value.

6. The method according to claim 5, characterized in that: When the first temperature sensor detects that the temperature of the circulating water is below 20°C, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase to full opening in increments of 5%. When the second temperature sensor detects that the temperature of the circulating water is below 30°C, it controls the opening of the second three-way valve at the radiator end to be 0.

7. The method according to claim 6, characterized in that: When the circulating water temperature sensed by the first temperature sensor is higher than 20℃ and lower than 45℃, the opening of the first three-way valve at the heat exchanger end is gradually reduced by 2%. When the circulating water temperature sensed by the second temperature sensor is higher than 30℃ and lower than 55℃, the opening of the second three-way valve at the radiator end is gradually increased by 2%. When the first temperature sensor detects that the temperature of the circulating water is higher than 45°C, it controls the opening of the first three-way valve at the heat exchanger end to gradually increase by 3%. When the second temperature sensor detects that the temperature of the circulating water is higher than 55°C, it controls the opening of the second three-way valve at the radiator end to gradually increase by 5%.

8. The method according to claim 7, characterized in that: By adjusting the flow rate and volume of cooling water in the cooling water circuit, the cooling water of the ship's methanol engine is used to gradually increase the temperature of the circulating water in the fuel cell reactor from startup to normal operation, and then stabilize it at the operating temperature of the fuel cell. This improves the efficiency of the combined heat and power system and reduces greenhouse gas emissions and energy consumption.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to implement the method as claimed in claims 5-8.

10. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, it implements the method of claims 5-8.

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