A SOFC power supply integrated device based on chemical hydrogen production and its control method

Abstract

This invention relates to the field of fuel cell technology, specifically to a SOFC (Solar-Oxygen Fuel Cell) power integrated device based on chemical hydrogen production. The device includes a housing containing an aluminum-water hydrogen production unit, an SOFC battery, a heat exchange assembly, and a temperature detection module. A first pipeline for supplying hydrogen and a second pipeline for supplying air are connected between the aluminum-water hydrogen production unit and the SOFC battery. The aluminum-water hydrogen production unit supplies hydrogen and air to the SOFC battery. The heat exchange assembly uses the exhaust gas generated by the SOFC battery to heat the hydrogen and air. The temperature detection module detects the temperature. In the device provided by this invention, the high-temperature exhaust gas generated by the SOFC battery heats the hydrogen and air through the heat exchange assembly. Simultaneously, the aluminum-water hydrogen production unit also uses its internal heat exchange system to preheat the air, ensuring that the fuel temperature entering the SOFC battery meets the reaction requirements. Through the coupled use of aluminum-water hydrogen production and the SOFC, the power generation efficiency of the device is effectively improved.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, specifically to an SOFC power integrated device and its control method based on chemical hydrogen production. Background Technology

[0002] Solid oxide fuel cells (SOFCs) are a typical type of high-temperature fuel cell that can directly convert the chemical energy in fuel into electrical energy at high temperatures, making them a clean and efficient energy conversion device. Compared to the other four common types of fuel cells—proton exchange membrane fuel cells (PEMFCs), alkaline fuel cells (AFCs), phosphoric acid fuel cells (PAFCs), and molten carbonate fuel cells (MCFCs)—PEMFCs and SOFCs are relatively small in size and are commonly used in portable devices. SOFCs have the highest reaction temperature, reaching 600-1000℃, thus eliminating the need for precious metal catalysts as electrode materials and significantly reducing fuel cell costs. At high temperatures, the SOFC anode exhibits catalytic activity, catalyzing the reforming of large-molecule fuels. Therefore, SOFCs can use not only hydrogen but also syngas, natural gas, ethanol, diesel, and other carbon-containing fuels, demonstrating broad fuel adaptability. The ability to directly use high-energy-density fuels like diesel ensures high energy-density output. They boast high power generation efficiency, reaching 50-70%, with low pollution and emissions during power generation. Furthermore, the absence of rotating parts results in low noise levels. SOFCs have broad application prospects in large, medium, and small-scale fixed / distributed power plants, mobile power plants, emergency power supplies, and portable power generation devices.

[0003] Currently, there are several solutions to address the difficulty of large-scale hydrogen production in remote areas or the field, such as hydrogen production through water electrolysis, methanol reforming, and water electrolysis. Water electrolysis is considered the most suitable solution for field hydrogen production due to its low power consumption, simple structure, and convenient refueling. Common water electrolysis methods include metal / water hydrogen production, ferrosilicon powder hydrogen production, and borohydride hydrogen production. Ferrosilicon powder hydrogen production uses strong alkalis, which is extremely unfriendly to equipment and operators; borohydride hydrogen production is too expensive and has high safety requirements, so current borohydride hydrogen production equipment is generally complex and unsuitable for field hydrogen production. Portable fuel cell technology for metal / water hydrogen production does not require hydrogen storage equipment and can produce hydrogen in real time on demand, eliminating the difficulties of hydrogen storage and transportation during use. Most commonly used metal / water hydrogen production equipment uses reactive metals such as aluminum and magnesium as reactants. Aluminum is relatively stable and the safest among the various reactants, making aluminum-water hydrogen production a more common application. Compared to other chemical hydrogen production methods, aluminum-water hydrogen production has significant advantages: the system has a moderate hydrogen storage density; the raw materials used are inexpensive, resulting in lower production costs; the produced hydrogen has high purity, directly meeting the needs of fuel cells; and both aluminum and water, the raw materials, are harmless to humans. However, aluminum-water hydrogen production is an exothermic reaction, generating a large amount of heat, with the produced hydrogen reaching temperatures above 100°C. For PEMFCs, the operating temperature is between 60°C and 80°C. Using aluminum-water hydrogen production as a hydrogen source presents several problems, including hydrogen cooling and filtration, and inefficient utilization of thermal energy. In contrast, SOFC fuel cell power generation utilizes SOFCs, whose reaction temperatures range from 600 to 1000°C, allowing most hydrocarbon fuels to be used as reactants. Therefore, aluminum-water hydrogen production devices can serve as a hydrogen source, perfectly coupled with SOFCs for power generation.

[0004] Existing portable SOFC power supplies based on chemical hydrogen production mostly utilize reforming hydrogen production equipment to provide hydrogen-rich synthesis gas. This type of power supply equipment technology is relatively mature. However, reforming hydrogen production is an endothermic process, which usually requires 300℃ to 800℃ to ensure the normal progress of the reaction. Therefore, a large amount of heat needs to be supplied to the reforming hydrogen production equipment from the outside to start the reaction when the power is turned on. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an integrated SOFC power supply device and its control method based on chemical hydrogen production. While ensuring the overall portability of the device, it efficiently combines aluminum water hydrogen production equipment with SOFC batteries. By leveraging the portability of solid aluminum powder and the wide availability of reaction water replenishment, the portable power supply product can be used normally in extremely harsh environments.

[0006] To achieve the above-mentioned technical effects, the present invention adopts the following technical solution:

[0007] A chemical hydrogen production-based SOFC power integrated device includes a housing, within which are an aluminum-water hydrogen production unit, an SOFC battery, a heat exchange component, and a temperature detection module. A first pipeline for transporting hydrogen and a second pipeline for transporting air are connected between the aluminum-water hydrogen production unit and the SOFC battery.

[0008] The aluminum-water hydrogen production unit is used to supply hydrogen and air to SOFC batteries;

[0009] The heat exchange component uses the exhaust gas generated by the SOFC battery to heat hydrogen and air.

[0010] The temperature detection module is used to detect the temperature of the SOFC battery, the aluminum-water hydrogen production unit, the first pipeline, and the second pipeline.

[0011] In the device provided by this invention, the high-temperature exhaust gas generated during the combustion of the SOFC battery is used to heat hydrogen and air through a heat exchange component. At the same time, the aluminum-water hydrogen production unit also uses its internal heat exchange system to preheat the air, so that the fuel temperature entering the SOFC battery meets the reaction requirements. By coupling aluminum-water hydrogen production with SOFC, the power generation efficiency of the device is effectively improved.

[0012] Preferably, the housing is provided with a first heat insulation cover and a second heat insulation cover inside, the second heat insulation cover is fitted outside the first heat insulation cover, the SOFC battery and the heat exchange component are disposed inside the first heat insulation cover, the aluminum-water hydrogen production unit is disposed between the second heat insulation cover and the first heat insulation cover, and the first pipeline and the second pipeline both pass through the first heat insulation cover.

[0013] Preferably, the heat exchange assembly includes an exhaust gas burner, a gas distributor, and a heat exchanger group. The SOFC battery is connected to the inlet end of the exhaust gas burner, and the outlet end of the exhaust gas burner is connected to the heat exchanger group. The heat exchanger group includes a hydrogen heat exchanger and an air heat exchanger. The hydrogen heat exchanger is located on the first pipeline, and the air heat exchanger is located on the second pipeline. The anode of the SOFC battery is also connected to the aluminum-water hydrogen production unit through the gas distributor.

[0014] The SOFC battery is housed inside the first insulation cover. The area inside the first insulation cover is a high-temperature zone due to the heat generated by the hydrogen combustion reaction in the SOFC battery. The area between the first and second insulation covers is a medium-temperature zone, where the temperature can be maintained above 200°C. Different reactions occur at different temperatures during the hydrogen production process from molten aluminum.

[0015] 2Al + 6H₂O = 2Al(OH)₃ + 3H₂↑ (1)

[0016] 2Al + 4H₂O = 2AlO(OH) + 3H₂↑ (2)

[0017] 2Al + 3H₂O = 2Al₂O₃ + 3H₂↑ (3)

[0018] From room temperature to 280°C, the aluminum-water reaction mainly proceeds according to reaction (1), producing hydrogen and aluminum hydroxide; from 280°C to 480°C, reaction (2) mainly proceeds, producing hydrogen and aluminum hydroxide; if the reaction temperature is higher than 480°C, reaction (3) mainly proceeds, producing hydrogen and aluminum oxide. The theoretical hydrogen storage densities of the above three reactions are 3.7 wt% (reaction (1)), 4.2 wt% (reaction (2)), and 5.3 wt% (reaction (3)), respectively. Under normal circumstances, the byproduct of the aluminum-water reaction is mainly aluminum hydroxide, whose material-based theoretical hydrogen storage density is 3.7 wt%. If the amount of water used is not considered, the hydrogen storage density can reach 11.1 wt%, which is exactly equivalent to the hydrogen storage density of water. Therefore, ensuring the temperature of the aluminum-water reaction will help to improve its hydrogen storage density. The aluminum-water reaction device of this product is placed in the medium-temperature zone and is insulated to keep the ambient temperature in the medium-temperature zone above 200℃, reducing the temperature difference between the ambient temperature and the aluminum-water hydrogen production unit, ensuring that the aluminum-water hydrogen production unit can continue to carry out reaction (3) and maintain a high level of hydrogen storage density. In addition, the SOFC anode tail gas is connected to the aluminum-water hydrogen production unit through a gas distributor to recycle and reuse the anode tail gas (the temperature of the anode tail gas is above 500℃), which can increase the overall reaction temperature and recover some of the water vapor generated by the SOFC battery reaction, further increasing the overall hydrogen storage density of the aluminum-water reaction.

[0019] Preferably, the SOFC battery uses a tubular stack; more preferably, the tubular stack includes an anode tube and a cathode tube, wherein the anode tube is NiO / (ZrO2). 0.89 (Sc2O3) 0.1 (CeO2) 0.01 (ScSZ) porous anode support tube, wherein the cathode tube is La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O3-δ / GDC porous cathode support tube.

[0020] Preferably, the SOFC battery further includes a power output unit, which is used to output the power generated by the SOFC battery to the outside.

[0021] Preferably, the integrated device further includes an induced draft fan for introducing air from outside the housing into the aluminum-water hydrogen production unit.

[0022] The present invention also provides a control method for the above-mentioned integrated device, including a power-on temperature control mode and a working state temperature control mode.

[0023] Preferably, the power-on temperature control mode is as follows:

[0024] When the integrated device is started, the aluminum-water hydrogen production unit is activated, the hydrogen production rate is adjusted, the heat generated by the aluminum-water hydrogen production unit is used to heat the air, the exhaust gas burner is activated, and the temperature of the first pipeline, the second pipeline and the SOFC battery is increased.

[0025] Simultaneously monitor the air temperature entering the cathode through the second pipeline. If the temperature reaches 500℃, the integrated device enters the working temperature control mode and ends the start-up temperature control mode. If the temperature does not reach 500℃, the coupling operation of the aluminum-water hydrogen production unit and the exhaust gas burner continues until the temperature reaches 500℃.

[0026] When the SOFC is started at room temperature or low temperature, the temperature of the SOFC battery is not sufficient for normal operation. Therefore, the aluminum-water hydrogen production unit that generates heat is started first. The temperature of the hydrogen produced is easily reached 500°C due to the heat generated by the reaction. However, the temperature of the air entering the aluminum-water hydrogen production unit for heating needs to be monitored. After the hydrogen and the cooler air enter the SOFC battery, they do not react. Instead, they go directly to the exhaust gas burner for combustion, which heats the air again. When the air temperature also reaches 500°C, the SOFC battery starts to work.

[0027] Preferably, the operating temperature control mode is as follows:

[0028] During the operation of the integrated device, the gas distributor is adjusted so that some of the anode tail gas can directly enter the aluminum water hydrogen production unit to heat the aluminum water hydrogen production unit, so that the reaction temperature of the aluminum water hydrogen production unit reaches and is maintained at 500℃.

[0029] The beneficial effects of this invention are:

[0030] 1. The integrated device provided by this invention realizes the efficient co-use of SOFC batteries and aluminum-water hydrogen production units. The aluminum-water hydrogen production unit heats the air required by the SOFC batteries, and at the same time, the exhaust gas of the SOFC batteries also heats the air intake of the aluminum-water hydrogen production unit and the SOFC batteries, so that the overall thermal energy is fully utilized, the hydrogen storage density of the aluminum-water hydrogen production unit is improved, and the power generation efficiency of the integrated device is also improved. At the same time, by utilizing the overall coupling design principle and the advantages of chemical hydrogen production, the integrated device achieves overall compactness and portability.

[0031] 2. The control method provided by this invention enables the device to quickly enter the working state after startup by controlling the internal temperature. During operation, the aluminum-water hydrogen production unit is operated efficiently by adjusting the gas distributor, which effectively ensures the hydrogen supply of the SOFC battery and extends the service life of the device. Attached Figure Description

[0032] Figure 1This is a schematic diagram of the SOFC power supply integrated device based on chemical hydrogen production provided in Example 1;

[0033] Figure 2 This is a temperature control flowchart of the SOFC power supply integrated device based on chemical hydrogen production provided in Example 2, wherein... Figure 2 (a) is a flowchart of the power-on temperature control mode. Figure 2 (b) is a flowchart of the temperature control mode in working state;

[0034] The components include: 1. Shell; 2. First insulation cover; 3. Second insulation cover; 101. Power output unit; 201. Aluminum-water hydrogen production unit; 202. Exhaust fan; 301. Gas distributor; 302. SOFC battery; 303. Tail gas burner; 304. Hydrogen heat exchanger; 305. Air heat exchanger; 306. First pipeline; 307. Second pipeline. Detailed Implementation

[0035] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0036] Example 1:

[0037] An integrated SOFC power supply device based on chemical hydrogen production, such as Figure 1 As shown, the device includes a housing 1, within which are housed an aluminum-water hydrogen production unit 201, an SOFC battery 302, a heat exchange assembly, an induced draft fan 202, and a temperature detection module. The SOFC battery 302 uses a tubular fuel cell stack. In this embodiment, the tubular fuel cell stack includes an anode tube and a cathode tube, wherein the anode tube is NiO / (ZrO2). 0.89 (Sc2O3) 0.1 (CeO2) 0.01 (ScSZ) porous anode support tube, wherein the cathode tube is La 0.6 Sr 0.4 Co 0.2 Fe 0.8 The SOFC battery 302 is equipped with a power output unit 101, which is used to output the power generated by the SOFC battery 302 to the outside. The aluminum water hydrogen production unit 201 and the SOFC battery 302 are connected by a first pipeline 306 for transporting hydrogen and a second pipeline 307 for transporting air.

[0038] The aluminum-water hydrogen production unit 201 is used to supply hydrogen and air to the SOFC battery 302;

[0039] The heat exchange component uses the exhaust gas generated by the SOFC battery 302 to heat hydrogen and air.

[0040] The temperature detection module is used to detect the temperature of SOFC battery 302, aluminum-water hydrogen production unit 201, first pipeline 306 and second pipeline 307;

[0041] The induced draft fan 202 is used to introduce air from outside the housing 1 into the aluminum water hydrogen production unit 201.

[0042] The housing 1 is internally provided with a first heat insulation cover 2 and a second heat insulation cover 3. The second heat insulation cover 3 is fitted over the first heat insulation cover 2. The SOFC battery 302 and the heat exchange assembly are disposed inside the first heat insulation cover 2. The aluminum-water hydrogen production unit 201 is disposed between the second heat insulation cover 3 and the first heat insulation cover 2. The first pipe 306 and the second pipe 307 both penetrate the first heat insulation cover 2. In this embodiment, the induced draft fan 202 and the power output unit 101 are both disposed between the housing 1 and the second heat insulation cover 3. The temperature inside the second heat insulation cover 3 will be maintained above 200°C due to the continuous reaction and heat release of the aluminum-water hydrogen production unit 201. Therefore, the induced draft fan 202 and the power output unit 101 are disposed outside the second heat insulation cover 3 to avoid damage to them due to high temperature.

[0043] The heat exchange assembly includes an exhaust gas burner 303, a gas distributor 301, and a heat exchanger group. The SOFC battery 302 is connected to the inlet end of the exhaust gas burner 303, and the outlet end of the exhaust gas burner 303 is connected to the heat exchanger group. The heat exchanger group includes a hydrogen heat exchanger 304 and an air heat exchanger 305. The hydrogen heat exchanger 304 is located on the first pipeline 306, and the air heat exchanger 305 is located on the second pipeline 307. The anode of the SOFC battery 302 is also connected to the aluminum-water hydrogen production unit 201 through the gas distributor 301.

[0044] Example 2:

[0045] A control method for an integrated device provided in Embodiment 1 is a power-on temperature control mode, such as... Figure 2 As shown in (a), the specific control process is as follows:

[0046] When the integrated device is started, the aluminum-water hydrogen production unit 201 is started, the hydrogen production rate is adjusted, the heat generated by the aluminum-water hydrogen production unit 201 is used to heat the air, the exhaust gas burner 303 is started, and the temperature of the first pipeline 306, the second pipeline 307 and the SOFC battery 302 is increased.

[0047] Simultaneously monitor the air temperature entering the cathode through the second pipeline 307. If the temperature reaches 500℃, the integrated device enters the working state temperature control mode and ends the start-up temperature control mode. If the temperature does not reach 500℃, the coupling operation of the aluminum water hydrogen production unit 201 and the exhaust gas burner 303 continues until the temperature reaches 500℃.

[0048] When the SOFC battery 302 is turned on at room temperature or low temperature, the temperature is not sufficient for normal operation. Therefore, the aluminum-water hydrogen production unit 201, which generates heat, is started first. The temperature of the hydrogen produced is easily reached 500°C due to the heat generated by the reaction. However, the temperature of the air entering the aluminum-water hydrogen production unit 201 for heating needs to be monitored. After the hydrogen and the cooler air enter the SOFC battery 302, they do not react. Instead, they go directly to the exhaust gas burner 303 for combustion, which heats the air again. When the air temperature also reaches 500°C, the SOFC battery 302 starts to work.

[0049] Example 3:

[0050] A control method for an integrated device provided in Embodiment 1 is a temperature control mode in the working state, such as... Figure 2 As shown in (b), the specific control process is as follows:

[0051] During the operation of the integrated device, the gas distributor 301 is adjusted so that some of the anode tail gas directly enters the aluminum water hydrogen production unit 201 to heat the aluminum water hydrogen production unit 201, so that the reaction temperature of the aluminum water hydrogen production unit 201 reaches and is maintained at 500℃.

Claims

1. A SOFC power supply integrated device based on chemical hydrogen production, characterized in that, Includes a housing (1), which contains an aluminum-water hydrogen production unit (201), an SOFC battery (302), a heat exchange component and a temperature detection module. The aluminum-water hydrogen production unit (201) and the SOFC battery (302) are connected by a first pipeline (306) for transporting hydrogen and a second pipeline (307) for transporting air. The aluminum-water hydrogen production unit (201) is used to supply hydrogen to the SOFC battery (302) and to preheat the air using the heat generated by the reaction of the aluminum-water hydrogen production unit (201). The heat exchange component uses the exhaust gas generated by the SOFC battery (302) to heat hydrogen and air to reach the hydrogen and air temperatures required for the SOFC battery (302) to operate. The temperature detection module is used to detect the temperature of the SOFC battery (302), the aluminum-water hydrogen production unit (201), the first pipeline (306), and the second pipeline (307); The housing (1) is provided with a first heat insulation cover (2) and a second heat insulation cover (3) inside. The second heat insulation cover (3) is fitted outside the first heat insulation cover (2). The SOFC battery (302) and the heat exchange component are arranged inside the first heat insulation cover (2). The aluminum-water hydrogen production unit (201) is arranged between the second heat insulation cover (3) and the first heat insulation cover (2). The area between the first heat insulation cover and the second heat insulation cover is a medium temperature zone, and the temperature in the medium temperature zone can be maintained above 200°C. The heat exchange assembly includes an exhaust gas burner (303), a gas distributor (301), and a heat exchanger group. The anode of the SOFC battery (302) is also connected to the aluminum-water hydrogen production unit (201) via the gas distributor (301).

2. The SOFC power supply integrated device as described in claim 1, characterized in that, The first pipe (306) and the second pipe (307) both penetrate the first insulation cover (2).

3. The SOFC power supply integrated device as described in claim 1, characterized in that, The SOFC battery (302) is connected to the inlet end of the exhaust gas burner (303), and the outlet end of the exhaust gas burner (303) is connected to the heat exchanger group. The heat exchanger group includes a hydrogen heat exchanger (304) and an air heat exchanger (305). The hydrogen heat exchanger (304) is located on the first pipeline (306), and the air heat exchanger (305) is located on the second pipeline (307).

4. The SOFC power supply integrated device as described in claim 1, characterized in that, The SOFC battery (302) also includes a power output unit (101) for outputting the power generated by the SOFC battery (302) to the outside.

5. The SOFC power supply integrated device as described in claim 1, characterized in that, The integrated device also includes an induced draft fan (202) for introducing air from outside the housing (1) into the aluminum-water hydrogen production unit (201) for preheating.

6. A control method for an SOFC power integrated device as described in any one of claims 1-5, characterized in that, This includes a power-on temperature control mode and a working temperature control mode.

7. The control method as described in claim 6, characterized in that, The power-on temperature control mode is as follows: When the integrated device is started, the aluminum-water hydrogen production unit (201) is started, the hydrogen production rate is adjusted, the heat generated by the aluminum-water hydrogen production unit (201) is used to heat the air, the tail gas burner (303) is started, and the temperature of the first pipeline (306), the second pipeline (307) and the SOFC battery (302) is increased. Simultaneously monitor the air temperature entering the cathode via the second pipeline (307): If the temperature reaches 500℃, the integrated device enters the working temperature control mode and ends the start-up temperature control mode. If the temperature does not reach 500°C, the coupling operation of the aluminum-water hydrogen production unit (201) and the exhaust gas burner (303) continues until the temperature reaches 500°C.

8. The control method as described in claim 6, characterized in that, The operating temperature control mode is as follows: During the operation of the integrated device, the gas distributor (301) is adjusted so that the anode tail gas directly enters the aluminum water hydrogen production unit (201) to heat the aluminum water hydrogen production unit (201) and make the reaction temperature of the aluminum water hydrogen production unit (201) reach and maintain 500℃.

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