Magnesium-based hydrogen storage tank with flameless combustion catalysis component and working method

Abstract

The invention provides a magnesium-based hydrogen storage tank with a flameless combustion catalytic component and a working method. The magnesium-based hydrogen storage tank comprises a tank body, a mixing area, a flameless combustion catalytic area and a hydrogen storage area are sequentially arranged in the tank body, the hydrogen storage area is filled with a magnesium-based hydrogen storage material, and the flameless combustion catalytic component is arranged in the flameless combustion catalytic area; a heat exchange channel is arranged in the magnesium-based hydrogen storage material, one end of the heat exchange channel is connected with a hot gas discharge channel, and the mixing area is communicated with the hydrogen storage area through a hydrogen channel; a hydrogen inlet, a hydrogen outlet and an air inlet are formed in the tank body. According to the invention, a flameless combustion catalysis part is adopted for hydrogen combustion. Under the action of a catalyst of the flameless combustion catalysis part, hydrogen is subjected to low-temperature and uniform catalytic combustion reaction on the inner surfaces of pores of the flameless combustion catalysis part, so that high-temperature concentration and explosion risks caused by traditional open fire combustion are avoided; in addition, the energy consumption is effectively reduced, and the working cost of hydrogen storage equipment is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen storage, and particularly relates to a magnesium-based hydrogen storage tank with a flameless combustion catalytic component and a working method thereof. Background Art

[0002] Hydrogen energy is a clean energy source that does not produce carbon emissions during its use and has characteristics such as high energy density, easy storage and conversion. Hydrogen storage technology is crucial in the hydrogen energy industrial chain and is a key link connecting hydrogen production and terminal utilization. Among many hydrogen storage materials, magnesium-based solid hydrogen storage materials have become a research hotspot due to their superior comprehensive performance. Such materials have a high hydrogen storage density (the mass fraction can reach 7.6%, and the volume density is about 110 g / L), can realize reversible hydrogen absorption and release at normal temperature and pressure, and magnesium resources are rich and the cost is low.

[0003] However, there are the following difficulties in the application of magnesium-based hydrogen storage: Since magnesium-based hydrogen storage materials need to be heated during the hydrogen release stage to maintain them within a specific temperature range, and the existing heating means usually use electric heating or hydrogen burners for heating; among them, the electric heating scheme requires a large amount of electric energy. Taking the hydrogen release stage as an example, usually 4.167 kWh of electricity is consumed to release 1 kilogram of hydrogen, and the electricity cost is high, which greatly increases the working cost of the hydrogen storage device; when using a hydrogen burner to heat magnesium-based hydrogen storage materials, the temperature is not easy to control, and during the hydrogen combustion heating process, the local combustion temperature is too high and the flame is concentrated, which is extremely easy to cause hydrogen leakage and diffusion, and there is a great explosion risk during the ignition process of the burner. Summary of the Invention

[0004] The purpose of the present invention is to solve the deficiencies in the prior art and provide a magnesium-based hydrogen storage tank with a flameless combustion catalytic component and a working method thereof.

[0005] The purpose of the present invention is achieved through the following technical solutions: A magnesium-based hydrogen storage tank with a flameless combustion catalytic component includes a tank body. A mixing area, a flameless combustion catalytic area, and a hydrogen storage area are sequentially arranged in the tank body. The hydrogen storage area is filled with magnesium-based hydrogen storage materials, and a flameless combustion catalytic component is arranged in the flameless combustion catalytic area; a heat exchange channel is arranged in the magnesium-based hydrogen storage materials. One end of the heat exchange channel is connected to a hot gas discharge channel, and the mixing area and the hydrogen storage area are connected through a hydrogen channel; a hydrogen inlet, a hydrogen outlet, and an air inlet are arranged on the tank body. In the hydrogen charging stage, a cooling gas or a combustion gas mixed with air and hydrogen is introduced into the mixing area. After passing through the flameless combustion catalytic area, the combustion gas forms a heating gas, and the heating gas is introduced into the heat exchange channel to enable the magnesium-based hydrogen storage materials to reach the hydrogen storage working temperature range or a cooling gas is introduced to reduce the temperature of the magnesium-based hydrogen storage materials. During the hydrogen release stage, part of the hydrogen released from the hydrogen storage area is passed into the mixing area and mixed with the air introduced through the air inlet to form a mixed combustion gas. The mixed combustion gas passes through the flameless combustion catalytic area and then enters the heat exchange channel to keep the magnesium-based hydrogen storage material stable within the hydrogen release operating temperature range.

[0006] Preferably, the flameless combustion catalytic component is made of a high-porosity ceramic material with a porosity of 70% - 90%, and the pore surface of the high-porosity ceramic material is coated with a platinum catalyst.

[0007] Preferably, the hydrogen release operating temperature range is within 300 - 380 °C; during the hydrogen release stage, when the temperature of the magnesium-based hydrogen storage material rises, the decomposition of magnesium hydride intensifies and the heat absorption increases, thereby inhibiting the temperature rise of the magnesium-based hydrogen storage material; when the temperature of the magnesium-based hydrogen storage material drops, the decomposition of magnesium hydride weakens and the heat absorption decreases, thereby inhibiting the temperature drop of the magnesium-based hydrogen storage material.

[0008] Preferably, the hydrogen storage operating temperature range is 200 °C - 300 °C.

[0009] Preferably, a hydrogen inlet valve is provided on the hydrogen inlet, a hydrogen outlet valve is provided on the hydrogen outlet, an air inlet valve is provided on the air inlet, and a hydrogen channel valve is provided on the hydrogen channel.

[0010] Preferably, the heat exchange channel is in a U shape.

[0011] A working method of a magnesium-based hydrogen storage tank with a flameless combustion catalytic component. During the hydrogen charging stage, first open the hydrogen channel, introduce air into the mixing area through the air inlet, introduce hydrogen through the hydrogen inlet. The hydrogen passes through the hydrogen storage area and then enters the mixing area through the hydrogen channel and mixes with the air in the mixing area to form a mixed combustion gas. The mixed combustion gas passes through the flameless combustion catalytic area and then enters the heat exchange channel to heat the magnesium-based hydrogen storage material to reach the hydrogen storage operating temperature range; after the magnesium-based hydrogen storage material reaches the hydrogen storage operating temperature range, close the hydrogen channel, and the hydrogen introduced through the hydrogen inlet reacts with the magnesium-based hydrogen storage material to form magnesium hydride; at the same time, introduce cooling gas into the air inlet, and the cooling gas flows through the heat exchange channel and cools the magnesium-based hydrogen storage material to keep the magnesium-based hydrogen storage material within the hydrogen storage operating temperature range; During the hydrogen release stage, first, a combustion gas mixture of hydrogen and air is introduced into the mixing zone through the air inlet. The combustion gas passes through the flameless combustion catalytic zone and then into the heat exchange channel to bring the magnesium-based hydrogen storage material to the preheating temperature range, enabling the magnesium-based hydrogen storage material to release hydrogen within this preheating temperature range. The released hydrogen is introduced into the mixing zone through the hydrogen channel. Subsequently, a portion of the hydrogen released from the magnesium-based hydrogen storage material passes through the hydrogen channel to the mixing zone and mixes with the air introduced through the air inlet to form a mixed combustion gas. The mixed combustion gas passes through the flameless combustion catalytic zone and then into the heat exchange channel to keep the magnesium-based hydrogen storage material stable within the hydrogen release operating temperature range. Another portion of the hydrogen released from the magnesium-based hydrogen storage material is discharged through the hydrogen outlet.

[0012] Preferably, during the hydrogen charging stage, when hydrogen is introduced through the hydrogen inlet, the pressure of the hydrogen is 2–10 MPa.

[0013] Preferably, the preheating temperature range is 200°C - 250°C.

[0014] Preferably, when a cooling gas is introduced into the air inlet during the hydrogen charging stage, the flow rate of the cooling gas is calculated by the following formula: ; In the formula, is the specific heat capacity at constant pressure of air, is the mass flow rate of the hydrogen released from the hydrogen storage zone, is the enthalpy change of the hydrogenation reaction, is the temperature of the magnesium-based hydrogen storage material, is the temperature of the cooling gas before introduction, is the heat transfer coefficient between the magnesium-based hydrogen storage material and the heat exchange channel; is the total heat exchange area of the heat exchange channel.

[0015] The beneficial effects of the present invention are as follows: 1. The present invention uses a flameless combustion catalytic component for hydrogen combustion. Through the catalytic action of the flameless combustion catalytic component, the hydrogen undergoes a low-temperature and uniform catalytic combustion reaction on the inner surface of the pores of the flameless combustion catalytic component, thus avoiding the high-temperature concentration and explosion risks brought by traditional open-flame combustion. Compared with the traditional combustion method, this method has almost no open flame during the combustion process, and the heat release is more gentle and controllable, significantly improving the safety and temperature uniformity of the heating process.

[0016] 2. In the hydrogen release stage of the present invention, a flameless combustion catalytic component is used to catalytically combust hydrogen to release hydrogen. Only 0.125 kg of hydrogen needs to be combusted to release 1 kg of hydrogen. Under the same conditions, if an electric heating scheme is adopted, to release 1 kg of hydrogen, 4.167 kWh of electricity needs to be generated by a fuel cell, and the equivalent amount of hydrogen consumed to generate 4.167 kWh of electricity is 0.313 kg. Therefore, this scheme in the present invention effectively reduces the energy consumption and the operating cost of the hydrogen storage device.

[0017] 3. In the hydrogen storage stage, after entering the hydrogenation reaction process, cooling gas is introduced through the air inlet. The cooling gas is discharged outward through the hot gas discharge channel after passing through the heat exchange channel. At this time, the heat exchange channel serves as a cooling channel, and the magnesium-based hydrogen storage material is cooled through the heat exchange between the cooling gas and the magnesium-based hydrogen storage material. During hydrogen release, the combustion gas temperature is maintained between 400°C and 430°C by adjusting the size of the air inlet and the opening degree of the hydrogen valve in the mixing zone, so as to effectively control the temperature of the magnesium-based hydrogen storage material, which helps to maintain the good cycle stability and hydrogen storage efficiency of the magnesium-based material and avoid the occurrence of safety accidents.

[0018] 4. The structural design of the U-shaped heating tube provides a larger heat exchange surface area in a limited space. The arrangement of the heating pipes helps to achieve uniform distribution of the heat flow, reduce local overheating or overcooling phenomena, and thus improve the uniformity and efficiency of hydrogen absorption and release. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic structural diagram of the present invention.

[0020] Figure 2 is Figure 1 a cross-sectional view taken along the A-A direction in

[0021] In the figure: 1. Air inlet, 2. Air inlet valve, 3. Tank body, 4. Flameless combustion catalytic component, 5. Hydrogen inlet valve, 6. Hydrogen inlet, 7. Magnesium-based hydrogen storage material, 8. Heat exchange channel, 9. Hydrogen outlet, 10. Hydrogen outlet valve, 11. Hydrogen channel, 12. Fan, 13. Hot gas discharge channel, 15. Hydrogen inlet valve in the mixing zone. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present invention.

[0023] Such as Figures 1 to 2As shown in the figure, the present invention provides a magnesium-based hydrogen storage tank with a flameless combustion catalytic component, which includes a tank body 3. Inside the tank body 3, a mixing zone, a flameless combustion catalytic zone, and a hydrogen storage zone are sequentially arranged. The hydrogen storage zone is filled with a magnesium-based hydrogen storage material 7, and a flameless combustion catalytic component 4 is arranged in the flameless combustion catalytic zone; a heat exchange channel 8 is arranged inside the magnesium-based hydrogen storage material 7, and one end of the heat exchange channel 8 is connected to a hot gas discharge channel 13. The mixing zone and the hydrogen storage zone are communicated through a hydrogen channel 11; a hydrogen inlet 6, a hydrogen outlet 9, and an air inlet 1 are arranged on the tank body 3; among them, both the hydrogen inlet 6 and the hydrogen outlet 9 are communicated with the hydrogen storage zone, and the air inlet 1 is communicated with the mixing zone.

[0024] In the hydrogen charging stage, a cooling gas is introduced into the air inlet 1, or the hydrogen channel valve 15 and the air inlet valve 2 are opened to introduce a combustion gas mixed with air and hydrogen. After passing through the flameless combustion catalytic zone, the combustion gas forms a heating gas. The heating gas is introduced into the heat exchange channel 8 to enable the magnesium-based hydrogen storage material 7 to reach the hydrogen storage working temperature range, or a cooling gas is introduced to reduce the temperature of the magnesium-based hydrogen storage material 7; in the hydrogen release stage, the pressure of the hydrogen storage tank is 0.8 - 1.0 MPa. A part of the hydrogen reserved in the hydrogen storage zone is led to the mixing zone and mixed with the air introduced from the air inlet 1 to form a mixed combustion gas. After passing through the flameless combustion catalytic zone, the mixed combustion gas is introduced into the heat exchange channel 8 to keep the magnesium-based hydrogen storage material 7 stable in the hydrogen release working temperature range.

[0025] In this embodiment, the flameless combustion catalytic component 4 selects a porous ceramic flameless catalytic burner. The flameless combustion catalytic component 4 is made of a high-porosity ceramic material with a porosity of 70% - 90%, and the pore surface of the high-porosity ceramic material is coated with a platinum catalyst. And an electric heating component is arranged in the flameless combustion catalytic component 4, and this electric heating component is used to heat the high-porosity ceramic material to the catalytic working temperature.

[0026] In the present invention, when the mixed gas of air and hydrogen passes through the flameless combustion catalytic component 4, catalytic combustion will occur under the action of the platinum catalyst. There is almost no open flame during the whole catalytic combustion process, and the heat release is more gentle and controllable, significantly improving the safety and temperature uniformity of the heating process; the mixed gas of air and hydrogen forms a heating gas with a relatively high temperature after catalytic combustion. The heating gas will enter the heat exchange channel 8 and conduct heat exchange with the magnesium-based hydrogen storage material 7, so that the temperature of the magnesium-based hydrogen storage material 7 rises to the hydrogen storage working temperature range or the hydrogen release working temperature range; after passing through the heat exchange channel 8, the heating gas is discharged out of the tank body 3 through the hot gas discharge channel 13.

[0027] A hydrogen inlet valve 5 is arranged on the hydrogen inlet 6, a hydrogen outlet valve 10 is arranged on the hydrogen outlet 9, an air inlet valve 2 is arranged on the air inlet 1, and a mixing zone hydrogen inlet valve 15 is arranged on the hydrogen channel 11.

[0028] The present invention uses a flameless combustion catalytic component 4 for hydrogen combustion. Through the catalytic action of the flameless combustion catalytic component 4, the hydrogen undergoes a low-temperature and uniform catalytic combustion reaction on the inner surface of the pores of the flameless combustion catalytic component 4, thereby avoiding the high-temperature concentration and explosion risks brought by traditional open-flame combustion. Compared with the traditional combustion method, there is almost no open flame during the combustion process of this method, and the heat release is more gentle and controllable, significantly improving the safety and temperature uniformity of the heating process.

[0029] In the hydrogen release stage of the present invention, a flameless combustion catalytic component is used to catalytically combust hydrogen to release hydrogen. Only 0.125 kg of hydrogen needs to be combusted to release 1 kg of hydrogen; under the same conditions, if an electric heating scheme is adopted, to release 1 kg of hydrogen, the fuel cell needs to generate 4.167 kWh of electricity, and the equivalent amount of hydrogen consumed to generate 4.167 kWh of electricity is 0.313 kg. Therefore, this scheme in the present invention effectively reduces the energy consumption and the working cost of the hydrogen storage device.

[0030] Among them, the particles of the magnesium-based hydrogen storage material are in a spherical-like or approximately flaky morphology, and the particle size distribution is from 100 nm to 500 nm; the total specific surface area (BET) of the pores is between 500–1000 m2 / g. The material has a hierarchical pore structure, where the micropore aperture is 2 nm to 10 nm (accounting for about 30%–50% of the total specific surface area, that is, 150–500 m2 / g), the mesopore aperture is 10 nm to 50 nm (accounting for about 50%–70% of the total specific surface area, that is, 250–700 m2 / g), and the overall porosity of the magnesium-based hydrogen storage material is 30% to 60%.

[0031] In the hydrogen charging stage, it is necessary to first heat the magnesium-based hydrogen storage material 7 to reach the hydrogen storage working temperature range; during this process, hydrogen and air are introduced into the interior of the tank body 3 through the air inlet 1 and the hydrogen channel 11 to form a mixed combustion gas for heating. By heating, the temperature of the magnesium-based hydrogen storage material 7 can be increased, thereby increasing the collision frequency and energy between hydrogen molecules and the surface of the magnesium-based hydrogen storage material 7, and promoting the progress of the hydrogenation reaction; hydrogen is introduced into the hydrogen storage area through the hydrogen inlet 6, and the hydrogen reacts with the magnesium-based hydrogen storage material 7 to form magnesium hydride (MgH2).

[0032] When entering the hydrogenation reaction process, since the hydrogenation reaction itself is an exothermic reaction, a large amount of heat will be released, causing the temperature of the magnesium-based hydrogen storage material 7 to rise rapidly. To avoid a decrease in hydrogen storage performance or potential safety risks due to the excessive temperature of the magnesium-based hydrogen storage material 7, when the magnesium-based hydrogen storage material 7 reaches the hydrogen storage operating temperature range and starts hydrogen storage, cooling gas is introduced through the air inlet 1. The cooling gas can be air or some inert gases (such as nitrogen). After passing through the heat exchange channel 8, the cooling gas is discharged outward through the hot gas discharge channel 13. At this time, the heat exchange channel 8 serves as a cooling channel, and the magnesium-based hydrogen storage material 7 is cooled through the heat exchange between the cooling gas and the magnesium-based hydrogen storage material 7, thereby effectively controlling the temperature of the magnesium-based hydrogen storage material 7, helping to maintain the good cycle stability and hydrogen storage efficiency of the magnesium-based material, and avoiding the occurrence of safety accidents.

[0033] In the hydrogen release stage, the magnesium-based hydrogen storage material 7 decomposes to release hydrogen at a certain temperature. To improve the hydrogen release efficiency, in the present invention, the hydrogen is catalytically combusted by the flameless combustion catalytic component 4 and the magnesium-based hydrogen storage material 7 is heated to keep the magnesium-based hydrogen storage material 7 stable within the hydrogen release operating temperature range. By heating, magnesium hydride decomposes to produce hydrogen.

[0034] Among them, in the starting process of the hydrogen release stage, since the temperature of the magnesium-based hydrogen storage material 7 is relatively low (maintained at room temperature) and cannot release hydrogen, the magnesium-based hydrogen storage material 7 is heated by catalytic combustion of the combustion gas mixed with air and hydrogen introduced into the mixing zone through the air inlet. The magnesium-based hydrogen storage material 7 is heated to reach the temperature at which hydrogen can be released (i.e., the preheating temperature range). When the hydrogen storage tank is full of hydrogen, the pressure is 0.8 - 1 MPa. The intake fan provided at the air inlet is turned on, and air is introduced into the mixing zone through the air inlet valve. The hydrogen inlet valve 15 of the mixing zone is opened 10 seconds after the intake fan is turned on. The released hydrogen is introduced into the mixing zone through the hydrogen channel 11, and the magnesium-based hydrogen storage material releases hydrogen by heating with the hot gas generated by the catalytic combustor; after the hydrogen starts to be released, the hydrogen continuously passes through the hydrogen channel 11 into the mixing zone. The hydrogen released by the magnesium-based hydrogen storage material 7 forms a mixed combustion gas with air in the mixing zone. The mixed combustion gas forms a heating gas with a relatively high temperature after passing through the flameless combustion catalytic component 4, and then the magnesium-based hydrogen storage material 7 is heated by the mixed combustion gas to reach the hydrogen release operating temperature range; within the hydrogen release operating temperature range, the magnesium-based hydrogen storage material 7 releases a large amount of hydrogen. Among the released hydrogen, a small part of the hydrogen passes through the hydrogen channel 11 to the mixing zone and mixes with air to form a mixed combustion gas to maintain the temperature state of the magnesium-based hydrogen storage material 7; the rest of the hydrogen is all discharged through the hydrogen outlet 9 for external supply. The heating energy in the hydrogen release stage of the present invention all comes from the hydrogen stored in the magnesium-based hydrogen storage material 7 itself, reducing the dependence on external energy sources and achieving energy self-sufficiency in the entire hydrogen release stage.

[0035] Among them, the hydrogen storage operating temperature range is 200°C–300°C. The hydrogen release operating temperature range is within 300–380°C. During the hydrogen release stage, the opening of the hydrogen channel valve 15 is controlled at 20%–30% of the opening of the air inlet valve 2. By controlling the valve opening, the hydrogen proportion in the mixed combustion gas is controlled. At this proportion, after the catalytic combustion of the mixed combustion gas by the flameless combustion catalytic component 4, a heating gas with a temperature of 400–430°C will be formed, and the temperature of the magnesium-based hydrogen storage material 7 is controlled within the range of 300–380°C through this heating gas.

[0036] During the hydrogen release stage, when the temperature of the magnesium-based hydrogen storage material 7 rises, the decomposition of magnesium hydride intensifies and the heat absorption increases, thereby inhibiting the temperature rise of the magnesium-based hydrogen storage material 7; when the temperature of the magnesium-based hydrogen storage material 7 drops, the decomposition of magnesium hydride weakens and the heat absorption decreases, thereby inhibiting the temperature drop of the magnesium-based hydrogen storage material 7. Through the above characteristics, an internal negative feedback is formed during the hydrogen release stage, making the entire hydrogen release process have a self-stabilizing effect in the range of 300–380°C.

[0037] During the hydrogen release stage, the decomposition reaction of magnesium hydride (MgH2) is a strong endothermic process (the enthalpy of formation of MgH2 ≈ 75.2 kJ / mol, and the same amount of heat needs to be absorbed during decomposition). During hydrogen release, by gradually reducing the internal pressure of the storage tank (the pressure is usually controlled at 0.1–1 MPa, and can be further close to atmospheric pressure if necessary), the desorption of hydrogen can be promoted, and the magnesium hydride in the hydrogen storage material undergoes a reversible thermal decomposition reaction, decomposing into metallic magnesium and hydrogen, realizing the release of the stored hydrogen.

[0038] In this application, the heat exchange channel 8 is U-shaped.

[0039] A fan is provided at the outlet end of the hot gas discharge channel, and the fan is used for discharging the gas in the hot gas discharge channel.

[0040] In the design of the present invention, the tank diameter is set within the range of 180–250 mm, and the overall length of the tank is 800–1000 mm. Through the numerical simulation analysis of the system, the arrangement mode of the heat exchange channels is optimized, and the heat exchange channels are arranged in a rectangular array (as Figure 2 shown). The spacing between adjacent heat exchange tubes is 30–40 mm. This spacing not only fully ensures the uniformity of heat transfer, but also effectively avoids the occurrence of local overheating or temperature dead zones, making the temperature easy to control and improving the overall thermal management efficiency. The diameter of the heat exchange channel is controlled between 12–20 mm, and the internal gas flow rate is controlled at 1.5–2 m / s. Through thermodynamic calculation and simulation verification, this size range can achieve the best hydrogen storage and release performance in a limited space.

[0041] In addition, to meet the hydrogen storage requirements of different scales, the design has good scalability in terms of size setting. If a larger-capacity tank is needed, the overall size of the tank and its internal structure can be enlarged proportionally on the premise of keeping the above-mentioned tube spacing and the relative proportion of the heat exchange channels unchanged. This method of proportional expansion not only simplifies the complexity of the enlarged design but also ensures that the system can maintain excellent thermal management and hydrogen storage performance under different size conditions, with extremely high flexibility and replicability in engineering applications.

[0042] Example 2: The present invention provides a working method for a magnesium-based hydrogen storage tank with a flameless combustion catalytic component. In the hydrogen charging stage, first open the hydrogen channel, introduce air into the mixing zone through the air inlet, and introduce hydrogen through the hydrogen inlet. After passing through the hydrogen storage zone, the hydrogen enters the mixing zone through the hydrogen channel and mixes with the air in the mixing zone to form a mixed combustion gas. The mixed combustion gas passes through the flameless combustion catalytic zone and then enters the heat exchange channel to heat the magnesium-based hydrogen storage material so that the magnesium-based hydrogen storage material reaches the hydrogen storage working temperature range; after the magnesium-based hydrogen storage material reaches the hydrogen storage working temperature range, close the hydrogen channel, and the hydrogen introduced through the hydrogen inlet reacts with the magnesium-based hydrogen storage material to form magnesium hydride; at the same time, introduce cooling gas into the air inlet, and the cooling gas flows through the heat exchange channel to cool the magnesium-based hydrogen storage material so that the magnesium-based hydrogen storage material is maintained within the hydrogen storage working temperature range; In the hydrogen release stage, first introduce the combustion gas mixed with hydrogen and air into the mixing zone through the air inlet. The combustion gas passes through the flameless combustion catalytic zone and enters the heat exchange channel to make the magnesium-based hydrogen storage material reach the preheating temperature range, so that the magnesium-based hydrogen storage material releases hydrogen at the preheating temperature range; the released hydrogen passes through the hydrogen channel into the mixing zone, and then a part of the hydrogen released from the magnesium-based hydrogen storage material passes through the hydrogen channel to the mixing zone and mixes with the air introduced through the air inlet to form a mixed combustion gas. The mixed combustion gas passes through the flameless combustion catalytic zone and then enters the heat exchange channel to keep the magnesium-based hydrogen storage material stable within the hydrogen release working temperature range; another part of the hydrogen released from the magnesium-based hydrogen storage material is discharged through the hydrogen outlet.

[0043] Among them, in the hydrogen charging stage, when introducing hydrogen through the hydrogen inlet, the pressure of the hydrogen is 2–10 MPa.

[0044] The preheating temperature range is 200°C - 250°C.

[0045] Among them, when introducing cooling gas into the air inlet during the hydrogen charging stage, the flow rate of the cooling gas should be controlled. If the flow rate of the cooling gas is too large, the temperature of the magnesium-based hydrogen storage material will be too low, affecting the hydrogen storage efficiency; if the flow rate of the cooling gas is too small, due to poor cooling effect, the temperature of the magnesium-based hydrogen storage material will be too high, resulting in a decline in hydrogen storage performance or potential safety risks. In the present invention, the flow rate of the cooling gas is accurately controlled according to the actual operating conditions, so as to accurately control the cooling effect on the magnesium-based hydrogen storage material and avoid the temperature of the magnesium-based hydrogen storage material being too high or too low, specifically as follows: The heat release of the hydrogenation reaction is represented by The mass flow rate of the hydrogen released from the hydrogen storage area is represented by The enthalpy change of the hydrogenation reaction is and their relationship is: ; The heat of the magnesium-based hydrogen storage material is transferred to the cooling gas through the heat exchange channel, and the heat transfer equation is: ; where U is the heat transfer coefficient between the magnesium-based hydrogen storage material and the heat exchange channel; A is the total heat exchange area of the heat exchange channel, and ΔT avg is the average temperature difference, and ΔT avg is calculated using the following formula: ; is the temperature of the magnesium-based hydrogen storage material, is the temperature of the cooling gas before being introduced, and this temperature can be measured by a temperature sensor set on the air inlet; is the temperature of the cooling gas when it is discharged, and this temperature can be measured by a temperature sensor set at the outlet end of the hot gas discharge channel; U is the heat transfer coefficient between the magnesium-based hydrogen storage material and the heat exchange channel; A is the total heat exchange area of the heat exchange channel.

[0046] The heat carried away by the cooling gas is calculated by the following formula: ; where is the specific heat capacity at constant pressure of air, is the flow rate of the cooling gas.

[0047] Based on the principle of heat balance and the heat transfer equation, when introducing cooling gas into the air inlet during the hydrogen charging stage, the flow rate of the cooling gas is calculated by the following formula: .

[0048] The present invention is not limited to the above-mentioned optimal embodiments, and anyone can obtain other various forms of products under the inspiration of the present invention. However, no matter what changes are made in its shape or structure, as long as it has a technical solution that is the same as or similar to the present application, it falls within the protection scope of the present invention.

Claims

1. A magnesium-based hydrogen storage tank with a flameless combustion catalytic component, characterized in that, It includes a tank body, in which a mixing zone, a flameless combustion catalytic zone, and a hydrogen storage zone are successively arranged. A magnesium-based hydrogen storage material is filled in the hydrogen storage zone, and a flameless combustion catalytic component is arranged in the flameless combustion catalytic zone; a heat exchange channel is arranged inside the magnesium-based hydrogen storage material, one end of the heat exchange channel is connected to a hot gas discharge channel, and the mixing zone and the hydrogen storage zone are communicated through a hydrogen channel; a hydrogen inlet, a hydrogen outlet, and an air inlet are arranged on the tank body. In the hydrogen charging stage, a cooling gas or a combustion gas mixed with air and hydrogen is introduced into the mixing zone. After passing through the flameless combustion catalytic zone, the combustion gas forms a heating gas. The heating gas is introduced into the heat exchange channel to make the magnesium-based hydrogen storage material reach the hydrogen storage working temperature range or a cooling gas is introduced to lower the temperature of the magnesium-based hydrogen storage material. In the hydrogen release stage, part of the hydrogen released from the hydrogen storage zone is passed to the mixing zone and mixed with the air introduced through the air inlet to form a mixed combustion gas. After passing through the flameless combustion catalytic zone, the mixed combustion gas is introduced into the heat exchange channel to keep the magnesium-based hydrogen storage material stable within the hydrogen release working temperature range.

2. The magnesium-based hydrogen storage tank with flameless combustion catalytic components according to claim 1, wherein, The flameless combustion catalytic component uses a high-porosity ceramic material with a porosity of 70%-90%, and a platinum catalyst is coated on the pore surface of the high-porosity ceramic material.

3. A magnesium-based hydrogen storage tank with a flameless combustion catalytic component according to claim 1, characterized in that, The hydrogen release working temperature range is within 300–380 °C; in the hydrogen release stage, when the temperature of the magnesium-based hydrogen storage material rises, the decomposition of magnesium hydride intensifies and the heat absorption increases, thereby inhibiting the temperature rise of the magnesium-based hydrogen storage material; when the temperature of the magnesium-based hydrogen storage material drops, the decomposition of magnesium hydride weakens and the heat absorption decreases, thereby inhibiting the temperature drop of the magnesium-based hydrogen storage material.

4. A magnesium-based hydrogen storage tank with a flameless combustion catalytic component according to claim 1, characterized in that, The hydrogen storage working temperature range is 200 °C–300 °C.

5. A magnesium-based hydrogen storage tank with a flameless combustion catalytic component according to claim 1, characterized in that, A hydrogen inlet valve is arranged on the hydrogen inlet, a hydrogen outlet valve is arranged on the hydrogen outlet, an air inlet valve is arranged on the air inlet, and a hydrogen channel valve is arranged on the hydrogen channel.

6. The magnesium-based hydrogen storage tank with a flameless combustion catalytic component according to claim 1, wherein, The heat exchange channel is in a U shape.

7. A working method of a magnesium-based hydrogen storage tank with a flameless combustion catalytic component, characterized in that, In the hydrogen charging stage, first open the hydrogen channel, introduce air into the mixing zone through the air inlet, introduce hydrogen through the hydrogen inlet. After passing through the hydrogen storage zone, the hydrogen enters the mixing zone through the hydrogen channel and mixes with the air in the mixing zone to form a mixed combustion gas. After passing through the flameless combustion catalytic zone, the mixed combustion gas is introduced into the heat exchange channel to heat the magnesium-based hydrogen storage material to make the magnesium-based hydrogen storage material reach the hydrogen storage working temperature range; after the magnesium-based hydrogen storage material reaches the hydrogen storage working temperature range, close the hydrogen channel, and the hydrogen introduced through the hydrogen inlet reacts with the magnesium-based hydrogen storage material to form magnesium hydride; at the same time, introduce a cooling gas into the air inlet, and the cooling gas flows through the heat exchange channel to cool the magnesium-based hydrogen storage material to keep the magnesium-based hydrogen storage material within the hydrogen storage working temperature range. In the hydrogen release stage, first, combustion gas formed by mixing hydrogen and air is introduced into the mixing zone through the air inlet. The combustion gas passes through the flameless combustion catalytic zone and then into the heat exchange channel to heat the magnesium-based hydrogen storage material to the preheating temperature range, so that the magnesium-based hydrogen storage material releases hydrogen at the preheating temperature range. The released hydrogen is introduced into the mixing zone through the hydrogen channel. Subsequently, part of the hydrogen released from the magnesium-based hydrogen storage material passes through the hydrogen channel to the mixing zone and mixes with the air introduced through the air inlet to form mixed combustion gas. The mixed combustion gas passes through the flameless combustion catalytic zone and then into the heat exchange channel to keep the magnesium-based hydrogen storage material stable within the hydrogen release working temperature range. Another part of the hydrogen released from the magnesium-based hydrogen storage material is discharged through the hydrogen outlet.

8. The working method of a magnesium-based hydrogen storage tank with a flameless combustion catalytic component according to claim 7, characterized in that, In the hydrogen charging stage, when hydrogen is introduced through the hydrogen inlet, the pressure of the hydrogen is 2–10 MPa.

9. The working method of a magnesium-based hydrogen storage tank with a flameless combustion catalytic component according to claim 7, characterized in that The preheating temperature range is 200°C - 250°C.

10. The working method of a magnesium-based hydrogen storage tank with a flameless combustion catalytic component according to claim 7, characterized in that, When introducing cooling gas into the air inlet during the hydrogen charging stage, the flow rate of the cooling gas is calculated by the following formula: ； In the formula, is the specific heat capacity at constant pressure of air, is the mass flow rate of hydrogen released from the hydrogen storage area, is the enthalpy change of the hydrogenation reaction, is the temperature of the magnesium-based hydrogen storage material, is the temperature of the cooling gas before it is introduced, is the heat transfer coefficient between the magnesium-based hydrogen storage material and the heat exchange channel; is the total heat exchange area of the heat exchange channel.

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