Double-tank metal hydride hydrogen purification device

Abstract

The invention belongs to the technical field of hydrogen production, and particularly relates to a double-tank metal hydride hydrogen purification device which comprises a first tank body, a second tank body, a primary exhaust pipe, a gas communicating pipe, a first liquid passing bathroom, a second liquid passing bathroom, a circulating liquid bath chamber and a liquid communicating pipe. A first perforated pipe and a first metal hydride are arranged in the first tank body; and a second perforated pipe and a second metal hydride are arranged in the second tank body. The primary exhaust pipe is communicated with the first perforated pipe, and the gas communication pipe is communicated with the primary exhaust pipe and the second perforated pipe. And the first tank body and the second tank body are coated with the first liquid passing bathroom and the second liquid passing bathroom respectively. And the first liquid passing bathroom, the circulating liquid bath chamber, the second liquid passing bathroom and the liquid communicating pipe are communicated in sequence to form a liquid pipeline. Through the design of the circulating liquid bath chamber and the liquid communicating pipe, the hydrogen absorption and heat release process and the hydrogen desorption and heat absorption process are mutually compensated, the heat utilization efficiency is improved, the external heating and cooling requirements are reduced, and the energy consumption in the hydrogen purification process is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrogen production, and particularly relates to a dual-tank metal hydride hydrogen purification device. Background Art

[0002] As a clean energy source, hydrogen has the advantages of zero carbon emissions, high energy density, wide sources, and being storable and transportable. When hydrogen burns or is converted into electrical energy in a fuel cell, only water is generated, and no carbon dioxide or other greenhouse gases are produced. However, hydrogen often contains impurities such as water vapor, oxygen, carbon dioxide, and carbon monoxide during production and storage. These impurities not only affect the service life of fuel cells but also reduce the efficiency of the chemical synthesis process. Therefore, improving the purity of hydrogen has become a key link in the development of the hydrogen energy industry.

[0003] Currently, the purification technologies of hydrogen mainly include pressure swing adsorption, membrane separation, and cryogenic separation. The pressure swing adsorption technology uses adsorbents (such as zeolites, activated carbon, etc.) to selectively adsorb impurities under high pressure and desorb and regenerate under low pressure to achieve the purification of hydrogen. Pressure swing adsorption equipment usually requires multiple towers in parallel, occupies a large area, and has limited removal efficiency for certain impurities (such as carbon monoxide, methane). The membrane separation technology is based on the difference in the permeation rates of hydrogen and impurity gases in special membrane materials (such as hollow fiber membranes, metal membranes) to achieve separation. It is difficult for the membrane separation technology to reach ultra-high purity hydrogen, and it also has high requirements for the pressure of the input gas, with a limited scope of application. The cryogenic separation technology utilizes the boiling point difference between hydrogen and impurity gases to perform gas fractionation at extremely low temperatures to obtain high-purity hydrogen. This method is suitable for large-scale industrial production, but its disadvantage is extremely high energy consumption. It is necessary to cool down to below -250°C to achieve the separation of hydrogen, and the equipment cost is expensive, and the operation and maintenance costs are high.

[0004] The metal hydride hydrogen purification technology is based on the reversible adsorption and release characteristics of metal hydride materials. Through the selective adsorption of hydrogen by metal hydrides, the separation of high-purity hydrogen is achieved. Metal hydride materials can reversibly react with hydrogen under specific temperature and pressure conditions to store or release hydrogen. Metal hydrides have extremely high adsorption selectivity for hydrogen and can effectively remove impurities such as water, oxygen, carbon monoxide, carbon dioxide, and methane to achieve high-purity hydrogen of more than 99.999%. In addition, metal hydrides can work under lower pressures and do not require additional high-pressure equipment compared with pressure swing adsorption and membrane separation technologies, improving the safety of the system.

[0005] Although metal hydride hydrogen purification technology has the advantages of high purity, no loss, and low-pressure operation, it still faces a major challenge in its application: high energy consumption. Metal hydrides release heat when absorbing hydrogen and absorb heat when releasing hydrogen, which means that the hydrogen purification process requires additional heat management measures. During the hydrogen absorption stage, metal hydrides release heat. If the heat is not dissipated in time, the temperature will rise, the hydrogen absorption rate will be reduced, and the hydrogen purification efficiency will be affected. In the hydrogen release stage, metal hydrides need to absorb heat to release hydrogen, so an external heating device is required to provide sufficient heat to ensure the smooth desorption of hydrogen. Therefore, how to reduce the energy consumption in the metal hydride hydrogen purification process and improve the overall energy efficiency of the system has become a key issue for the further development of this technology. Summary of the invention

[0006] In order to solve the above problems, the present invention provides a double-tank metal hydride hydrogen purification device, including a first tank body, a second tank body, a primary exhaust pipe, a gas connecting pipe, a first liquid bath room, a second liquid bath room, a circulating liquid bath chamber, and a liquid connecting pipe. The first tank body is provided with a first porous pipe and a first metal hydride; the second tank body is provided with a second porous pipe and a second metal hydride. The primary exhaust pipe is connected to the first porous pipe, and the gas connecting pipe is connected to the primary exhaust pipe and the second porous pipe. The first liquid bath room and the second liquid bath room cover the first tank body and the second tank body respectively. The first liquid bath room, the circulating liquid bath chamber, the second liquid bath room, and the liquid connecting pipe are connected in sequence to form a liquid pipeline.

[0007] In the present application, the circulating liquid bath chamber, the first liquid bath chamber, the second liquid bath chamber, and the liquid connecting pipe form a liquid pipeline to realize the circulation of the liquid, which helps to evenly transfer heat, reduce local supercooling or overheating, and reduce external heating and cooling requirements. The present invention achieves low-energy operation of hydrogen purification by optimizing heat management, reducing external energy dependence, and improving the efficiency of the hydrogen absorption and release process.

[0008] Furthermore, it also includes a first valve, a second valve, a third valve, and a fourth valve; the first valve is a one-way valve, which is arranged on the intake pipe to ensure that hydrogen enters the system in one direction, prevents backflow, and improves the intake stability; the second valve is a back pressure valve, which is arranged on the outside of the gas connecting pipe on the primary exhaust pipe, and is used to adjust the pressure of the primary exhaust, prevent hydrogen from being discharged too quickly, and improve the hydrogen absorption efficiency of the metal hydride; the third valve is a switching valve, which is arranged on the gas connecting pipe to realize the alternating switching of the first tank body and the second tank body, so that the hydrogen purification process can be carried out continuously, avoiding stagnation caused by the operation of a single tank, and improving the system efficiency; the fourth valve is a back pressure valve, which is arranged on the outlet pipe to control the outlet pressure, ensure stable output of hydrogen, and avoid energy waste.

[0009] Furthermore, it also includes a liquid pump which is arranged in the liquid pipeline to make the liquid flow in the direction from the first liquid-passing bath to the second liquid-passing bath. During the operation of the liquid pump, the liquid flows out of the first liquid-passing bath, passes through the circulating liquid bath chamber, and then enters the second liquid-passing bath, realizing the continuous circulation of the liquid and adjusting the temperature distribution. By utilizing the heat transfer characteristics of the liquid, the liquid pump transports the heat released during the hydrogen absorption process in the first liquid-passing bath to the second liquid-passing bath, thereby compensating for the heat absorption required during the hydrogen release process of the second tank and improving the hydrogen release efficiency of the metal hydride. At the same time, this liquid circulation system can avoid local overcooling or overheating, maintain the thermal balance of the entire system, and reduce the need for external heating or cooling.

[0010] Furthermore, one end of the liquid connection pipe is connected to the end of the first liquid-passing bath near the air inlet pipe, and the other end of the liquid connection pipe is connected to the end of the second liquid-passing bath near the air outlet pipe. When hydrogen enters the first tank for hydrogen absorption, the metal hydride releases heat. The liquid connection pipe starts to transport the liquid from the air inlet end of the first liquid-passing bath, making it carry the excess heat and flow towards the second liquid-passing bath, thereby compensating for the heat absorption required during the hydrogen release process and improving the hydrogen release efficiency. In addition, this liquid flow path conforms to the hydrogen flow direction, ensuring that the liquid evenly takes away heat during the flow process, avoiding local overheating or overcooling, reducing the dependence on external heating and cooling equipment, and reducing energy consumption. At the same time, this layout improves the heat exchange uniformity of the system, makes the hydrogen adsorption and release processes more stable, helps to maintain the optimal working state of the metal hydride, and enhances the stability and efficiency of hydrogen purification.

[0011] Furthermore, it also includes a plurality of heat pipes which are arranged between the first liquid-passing bath and the second liquid-passing bath. As highly efficient heat transfer components, the heat pipes can conduct heat quickly and achieve heat self-balance during the processes of hydrogen absorption with heat release and hydrogen release with heat absorption. When the first tank absorbs hydrogen and releases heat, the heat pipes can quickly transfer the excess heat to the second liquid-passing bath, compensating for the heat absorption required during the hydrogen release process of the second tank and making the hydrogen release process smoother, thus enhancing the hydrogen release efficiency. Conversely, during the working mode switch, the heat pipes can also transfer heat to the first tank to increase its hydrogen absorption rate. This direct heat exchange method reduces the dependence on external heating and cooling systems, reduces additional energy consumption, and at the same time avoids the system instability phenomenon caused by excessive local temperature fluctuations.

[0012] Furthermore, it also includes a heating system and a temperature measurement system. The heating system is used to heat the liquid in the circulating liquid bath chamber. The temperature measurement system includes at least one temperature sensor installed in the circulating liquid bath chamber for real-time monitoring of the liquid temperature. The heating system is used to heat the circulating liquid during the hydrogen release stage to ensure that the metal hydride can smoothly release hydrogen and prevent the hydrogen release rate from decreasing due to insufficient temperature. At the same time, when the system temperature is too high, the heating system can cooperate with other cooling mechanisms to reduce unnecessary heat input and avoid energy consumption waste. Through the coordinated operation of the temperature measurement system and the heating system, intelligent temperature control is achieved to ensure that the hydrogen absorption and release process of the metal hydride always remains within the optimal operating temperature range, improve the hydrogen purification efficiency, reduce external energy consumption, and enhance the long-term stability and reliability of the system.

[0013] Furthermore, it also includes a flow control device and a pressure measurement device. The flow control device and the pressure measurement device are arranged on the inlet pipe for precisely adjusting the input state of hydrogen to optimize the stability and efficiency of the hydrogen purification process. The pressure measurement device real-time monitors the hydrogen pressure in the inlet pipe to ensure that the hydrogen maintains within a suitable operating pressure range when entering the metal hydride adsorption system, avoiding the influence on the hydrogen absorption efficiency due to too low pressure or the excessive equipment load and the impact on system safety due to too high pressure. The flow control device is used to adjust the hydrogen inlet rate to match the hydrogen absorption capacity of the metal hydride, preventing incomplete adsorption due to too fast gas flow or reducing the system efficiency due to too low flow rate. In addition, the coordinated operation of the two can achieve precise control of hydrogen input, ensure that the hydrogen reaches the optimal pressure and flow rate before entering the system, improve the hydrogen adsorption efficiency, reduce unnecessary gas loss, and ensure the long-term stable operation of the device at the same time.

[0014] Furthermore, it also includes a first porous branch pipe. The first porous branch pipe is arranged in the first tank body, and one end of the first porous branch pipe is connected to the holes of the first porous pipe. This optimizes the uniformity of hydrogen distribution inside the first tank body and improves the hydrogen adsorption efficiency. Since the hydrogen absorption reaction of the metal hydride depends on the sufficient contact between hydrogen and the material, a single porous pipe leads to uneven gas distribution inside the tank body, thus affecting the hydrogen absorption rate. The addition of the first porous branch pipe enables hydrogen to be more evenly transported to the metal hydride layer, avoiding problems such as local gas retention or poor flow. In addition, this design can reduce the flow resistance and the pressure drop of hydrogen before entering the metal hydride layer, ensure the uniform diffusion of hydrogen throughout the tank body, thereby improving the stability of the hydrogen absorption process and the utilization rate of the metal hydride, and ultimately enhancing the overall efficiency of hydrogen purification.

[0015] Furthermore, the other end of the first porous branch pipe is fixedly connected to the inner wall of the first tank body. The first porous branch pipe is in direct contact with the inner wall of the first tank body, and can accelerate the heat released during hydrogen absorption by metal hydride through heat conduction, enabling it to be transferred to the liquid bath system outside the first tank body more quickly, improving the heat dissipation efficiency, and avoiding excessive local temperature from affecting the hydrogen absorption rate. In addition, the fixed connection prevents the first porous branch pipe from displacing or vibrating during air flow impact or long-term operation, improving the durability of the system and reducing mechanical losses.

[0016] Furthermore, it further includes a second porous branch pipe, which is arranged inside the second tank body, and one end of the second porous branch pipe communicates with the holes of the second porous pipe. The function of the second porous branch pipe is similar to that of the first porous branch pipe.

[0017] Furthermore, the other end of the second porous branch pipe is fixedly connected to the inner wall of the second tank body, and its function is similar to that of the first porous branch pipe.

[0018] Furthermore, it further includes a first ultrasonic source, which is fixed on the intake pipe, and the first ultrasonic source generates ultrasonic waves along the direction from the intake pipe to the primary exhaust pipe. First of all, the ultrasonic vibration can enhance the fluidity of hydrogen, reduce the aggregation effect between gas molecules, enable hydrogen to enter the first tank body more evenly, and improve the hydrogen absorption rate of metal hydride. Secondly, ultrasonic waves have micro-perturbation and cavitation effects, which can promote the gas diffusion and penetration on the surface of metal hydride, enabling hydrogen to enter the microporous structure of the material more quickly and optimizing the hydrogen absorption process. In addition, ultrasonic waves can effectively prevent gas retention and boundary layer effects, avoiding the formation of dead corners or areas with too high local concentration during the flow of hydrogen, thereby improving the distribution uniformity of hydrogen inside the entire tank body. Finally, this design can also reduce the adsorption resistance on the surface of metal hydride particles, improve the hydrogen mass transfer efficiency, thereby enhancing the overall performance of the hydrogen purification system, making hydrogen purification more efficient, stable, and reducing energy consumption.

[0019] Furthermore, it further includes a second ultrasonic source, which is fixed near the second tank body on the gas connection pipe, and the second ultrasonic source generates ultrasonic waves along the direction from the gas connection pipe to the exhaust pipe. The function of the second ultrasonic source is similar to that of the first ultrasonic source.

[0020] Furthermore, the first porous branch pipe is inclined in the direction from the intake pipe to the primary exhaust pipe, and the second porous branch pipe is inclined in the direction from the gas connection pipe to the outlet pipe. The inclined arrangement can guide the hydrogen to diffuse along the optimal path, reduce the retention and short-circuit effect of the gas flow in the metal hydride layer, ensure the uniform distribution of hydrogen throughout the tank body, and improve the hydrogen absorption and desorption efficiency. In addition, the inclined structure can reduce the flow resistance, make the hydrogen enter the metal hydride layer more smoothly, reduce the local pressure loss, and improve the overall flow stability of the system. Moreover, this design can also avoid the formation of high-concentration regions of hydrogen in the tank, prevent the problem of uneven hydrogen absorption or desorption caused by too high or too low local hydrogen concentration, and improve the utilization rate of the metal hydride.

[0021] Furthermore, the middle pipe walls of the first and second porous branch pipes are thin. The aggregation of ultrasonic waves in the thinner pipe wall area will enhance the local enhancement effect, thereby reducing the adsorption resistance on the surface of the metal hydride, increasing the transmission speed of hydrogen in the metal hydride layer, optimizing the hydrogen absorption and desorption efficiency, and also reducing the flow resistance of hydrogen inside the tank body and improving the gas distribution uniformity.

[0022] Advantages of the present invention: (1) Through the design of the circulating liquid bath chamber and the liquid connection pipe, the present invention enables the hydrogen absorption heat release and desorption heat absorption processes to compensate each other, improves the heat utilization efficiency, reduces the need for external heating and cooling, and lowers the energy consumption in the hydrogen purification process.

[0023] (2) The present invention adopts a dual-tank alternating working mechanism, which improves the working continuity compared with the traditional single-tank system and does not require complex multi-stage adsorption equipment.

[0024] Combining the above beneficial effects, the present invention has good application prospects in the field of hydrogen production technology. Description of the Drawings

[0025] Figure 1 It is a schematic diagram of a dual-tank metal hydride hydrogen purification device.

[0026] Figure 2 It is a schematic diagram of the first tank body and the first ultrasonic source.

[0027] In the figure: 1, intake pipe; 2, first tank body; 3, second tank body; 4, primary exhaust pipe; 5, gas connection pipe; 6, first liquid bath chamber; 7, second liquid bath chamber; 8, circulating liquid bath chamber; 9, liquid connection pipe; 10, outlet pipe; 11, first valve; 21, first porous pipe; 22, first porous branch pipe; 31, second porous pipe; 41, second valve; 51, third valve; 101, fourth valve; 111, first ultrasonic source. Detailed Embodiments

[0028] To make the objectives, technical solutions and advantages of this application more clearly understood, the following examples are provided with reference to the accompanying drawings to further elaborate on this application in detail.

[0029] Example 1 The present invention provides a dual-tank metal hydride hydrogen purification device, as Figure 1 shown, which includes a first tank 2, a second tank 3, a primary exhaust pipe 4, a gas connection pipe 5, a first liquid bath 6, a second liquid bath 7, a circulating liquid bath chamber 8, and a liquid connection pipe 9. The first tank 2 and the second tank 3 are made of stainless steel (SS316L) or aluminum alloy to ensure good corrosion resistance and high strength. The first metal hydride is provided inside the first tank 2. The second metal hydride is provided inside the second tank 3. The first metal hydride and the second metal hydride are nickel-based metal hydrides, iron-titanium-based metal hydrides, titanium-zirconium-based metal hydrides, magnesium-based metal hydrides, or composite metal hydrides. A first porous pipe 21 is installed inside the first tank 2, and its material is porous stainless steel with a pore diameter of 0.1 mm to 0.5 mm, which is used to evenly distribute hydrogen and improve the adsorption efficiency. At the same time, a second porous pipe 31 is provided inside the second tank 3, and its structure is similar to that of the first porous pipe 21 to ensure the uniformity of gas distribution during the hydrogen release process.

[0030] Hydrogen enters the system through the inlet pipe 1, which is made of 316L stainless steel and can withstand the flow of high-pressure hydrogen. A first valve 11 is provided on the inlet pipe 1. The first valve 11 is a high-pressure-resistant one-way valve to prevent gas backflow and ensure that hydrogen enters the first tank 2 unidirectionally. The first valve 11 has a low opening pressure (such as 0.01 to 0.05 MPa). The primary exhaust pipe 4 is connected to the first porous pipe 21 inside the first tank 2, and a second valve 41 is installed outside the primary exhaust pipe 4. The second valve 41 is a spring-loaded backpressure valve, which is used to stabilize the primary exhaust pressure and avoid the too-fast exhaust during the hydrogen absorption process from affecting the hydrogen absorption efficiency of the metal hydride. The set pressure range of the second valve 41 is between 0.1 and 0.5 MPa.

[0031] The gas connection pipe 5 connects the primary exhaust pipe 4 and the second porous pipe 31, and is made of a titanium alloy pipe to ensure that hydrogen is not corroded during the flow process and reduce impurity pollution. A third valve 51 is provided on the gas connection pipe 5. The third valve 51 is an electromagnetic switching valve, which is used to switch the hydrogen flow direction, enabling the device to work alternately between the two tanks and ensuring continuous hydrogen purification. The third valve 51 has a fast response speed, and the opening time is controlled within the range of 50 to 200 ms to reduce the flow rate fluctuation during the hydrogen purification process. The outlet pipe 10 is connected to the exhaust end of the second tank 3, and a fourth valve 101 is installed on the outlet pipe 10. The fourth valve 101 is a precision backpressure regulating valve with a pressure regulation range of 0.01 to 1 MPa, which is used to control the final discharge pressure of hydrogen and ensure stable hydrogen output.

[0032] To optimize thermal management, the first liquid - passing bath 6 and the second liquid - passing bath 7 respectively wrap the first tank body 2 and the second tank body 3. The liquid connection pipe 9 is made of high - temperature resistant silicone tube or stainless - steel bellows. One end is connected to one end of the first liquid - passing bath 6 near the air inlet pipe 1, and the other end is connected to one end of the second liquid - passing bath 7 near the air outlet pipe 10 to achieve heat transfer between the two tank bodies.

[0033] The circulating liquid - bath chamber 8 adopts a closed - type design and is filled with heat - conducting oil (high - temperature silicone oil) or water - ethylene glycol mixture to ensure uniform heat transfer. The liquid - bath circulation is driven by a liquid pump, which is a magnetic - drive leak - free pump. The flow rate is controlled at 1 - 5 L / min to ensure that the liquid flows in the direction from the first liquid - passing bath 6 to the second liquid - passing bath 7, effectively transferring heat, balancing temperature changes, and reducing external energy consumption. The pump body is made of high - temperature resistant stainless steel or corrosion - resistant engineering plastics.

[0034] In addition, to further optimize heat exchange, multiple heat pipes (made of copper - aluminum alloy composite material, with a length of 100 mm - 300 mm) are installed between the first liquid - passing bath 6 and the second liquid - passing bath 7. They are used to achieve rapid heat transfer during the hydrogen - absorption exothermic and hydrogen - desorption endothermic processes, improve the system energy efficiency, and reduce additional heating and cooling requirements. The inside of the heat pipe uses a low - melting - point metal or a synthetic working fluid (such as water - ethanol mixture) to achieve efficient energy transfer through phase - change heat transfer.

[0035] This device also includes a heating system and a temperature - measuring system to further optimize system temperature control. The heating system includes a resistance heating element (with a power of 500 W - 1000 W), which is installed inside the circulating liquid - bath chamber 8 and can be dynamically adjusted according to temperature requirements. The temperature - measuring system includes a thermal resistance temperature sensor (with an accuracy of ±0.1 °C), which is arranged inside the circulating liquid - bath chamber 8 to monitor the liquid temperature in real - time and adjust the heating power through a PID intelligent control system to prevent excessive temperature fluctuations and improve the hydrogen - absorption and hydrogen - desorption stability of the metal hydride.

[0036] A flow - control device and a pressure - measuring device are installed on the air inlet pipe 1. The flow - control device uses a mass flowmeter (0 - 10 SLPM, adjustable) to accurately control the hydrogen flow rate, ensure that hydrogen enters the tank body at a set rate, and avoid over - amount or under - amount affecting the purification effect. The pressure - measuring device uses a digital pressure sensor (with a measurement range of 0 - 5 MPa) to monitor the inlet pressure in real - time, ensure that hydrogen enters the system within the optimal working pressure range, and improve the hydrogen - absorption efficiency and system safety.

[0037] This embodiment is also provided with an air pressure detection system and a gas temperature measurement system, which are used to monitor the hydrogen absorption saturation state of metal hydrides, hydrogen flow pressure and system temperature changes in real time, optimize hydrogen purification efficiency, and improve the safety and stability of the device. The air pressure detection system includes a digital pressure sensor (measuring range 0~5MPa, accuracy ±0.01MPa), which is installed at the air inlet pipe 1, the primary exhaust pipe 4 and the air outlet pipe 10 respectively, to ensure that the hydrogen is in the optimal pressure range during the process of entering the tank body, passing through the gas connecting pipe 5 and finally outputting. Through the air pressure sensor data, the control system can accurately determine whether the hydrogen absorption is completed (when the air pressure drops to a stable value, it indicates that the hydrogen absorption is saturated), and adjust the opening of the second valve 41 during the hydrogen release stage, so that the impurity gas (such as N2, O2, CO2) is discharged at an appropriate pressure, while ensuring the output of high-purity hydrogen. The gas temperature measurement system uses a platinum resistance temperature sensor (temperature measurement range -50~200℃, accuracy ±0.1℃), which is installed in the air inlet pipe 1, the first tank body 2, and the second tank body 3 respectively, to monitor the temperature before hydrogen enters the metal hydride and the temperature changes during the metal hydride hydrogen absorption / desorption process. Combined with the intelligent temperature control system, if the desorption temperature is detected to be too low, the control system will automatically increase the power of the heating system to accelerate the release of hydrogen; if the temperature is too high during hydrogen absorption, the flow rate of the liquid pump 51 is adjusted to allow the circulating liquid bath liquid to take away heat faster and reduce external cooling energy consumption. In addition, combined with the air pressure and temperature monitoring data, the system can optimize the switching timing of the hydrogen absorption / desorption mode to ensure that the device always operates in the best working conditions, further improving the stability, energy efficiency and safety of hydrogen purification.

[0038] The device realizes continuous purification of hydrogen and improves the purity of hydrogen by alternately absorbing, removing impurities and releasing hydrogen in the first tank 2 and the second tank. The specific process is as follows: (1) The first stage: the first tank 2 absorbs hydrogen The first valve 11 is opened, and hydrogen enters the first tank body 2 from the air inlet pipe 1. The first metal hydride in the first tank body 2 begins to absorb hydrogen. During the hydrogen absorption process, the first tank body 2 releases heat, and the liquid pump is started to push the liquid from the first liquid bath chamber 6 to the second liquid bath chamber 7 through the circulating liquid bath chamber 8, taking away the heat and improving the hydrogen absorption efficiency. The second valve 41 is partially opened to allow the impurity gas inside the first tank body 2 to be discharged to the outside, thereby improving the purity of the hydrogen. After the impurities are discharged, the second valve 41 is closed. During this period, the third valve 51 is closed to prevent insufficiently purified hydrogen from entering the second tank body 3, ensuring that the first tank body 2 undergoes independent primary purification.

[0039] (2) Second stage: The first tank 2 releases hydrogen, and the second tank 3 absorbs hydrogen (second stage purification) After the first hydrogen absorption tank 2 has completed hydrogen absorption, the third valve 51 is opened and the second valve 41 is closed to ensure that the purified hydrogen gas in the first hydrogen absorption tank 2 flows into the second hydrogen absorption tank 3 without leakage or direct discharge. The first hydrogen absorption tank 2 starts to release hydrogen. The hydrogen gas released from the first hydrogen absorption tank 2 enters the second hydrogen absorption tank 3 through the third valve 51, and the second metal hydride adsorbs hydrogen gas again to complete the second-stage purification and further improve the hydrogen purity.

[0040] (3) The third stage: The second hydrogen absorption tank 3 discharges impurities After the second hydrogen absorption tank 3 has completed hydrogen absorption, the third valve 51 is closed. The fourth valve 101 is partially opened to discharge a small amount of residual impurity gas in the second hydrogen absorption tank 3.

[0041] (4) The fourth stage: The second hydrogen absorption tank 3 releases hydrogen The second hydrogen absorption tank 3 starts to release hydrogen, and the fourth valve 101 is opened to ensure that the final high-purity hydrogen gas enters the outlet pipe 10 to complete the two-stage purification.

[0042] In short, the double-tank two-stage purification mode is adopted, that is: when the first hydrogen absorption tank 2 absorbs hydrogen, the third valve 51 is closed to prevent unpurified hydrogen gas from entering the second hydrogen absorption tank 3; when the first hydrogen absorption tank 2 releases hydrogen, the third valve 51 is opened and the second valve 41 is closed to ensure that hydrogen gas enters the second hydrogen absorption tank 3 for deep purification; after the second hydrogen absorption tank 3 absorbs hydrogen, impurities are discharged first and then hydrogen is released to ensure that the finally discharged hydrogen gas reaches a high purity. The double-tank two-stage purification design of the present invention is applicable to scenarios with high-purity hydrogen gas requirements (such as fuel cells, aerospace hydrogen supply, fine chemical industry, etc.), and can ensure an efficient, stable and low-energy-consuming hydrogen purification process.

[0043] Embodiment 2 On the basis of Embodiment 1, this embodiment further optimizes the flow and distribution of hydrogen gas inside the hydrogen absorption tank, such as Figure 2 As shown, by adding the first porous branch pipe 22 and the second porous branch pipe, the diffusion uniformity of hydrogen gas in the metal hydride layer is improved, the hydrogen absorption and hydrogen release efficiency is increased, and the hydrogen purification process is further optimized.

[0044] In this embodiment, a first porous branch pipe 22 is added inside the first tank body 2. The material of the first porous branch pipe 22 is selected as 316L stainless steel or titanium alloy to ensure resistance to high-pressure hydrogen environment and prevent the material from corroding due to long-term operation. One end of the first porous branch pipe 22 is connected to the holes of the first porous pipe 21 to ensure that hydrogen can smoothly flow from the first porous pipe 21 to the first porous branch pipe 22 and further uniformly diffuse into the entire metal hydride layer, improving the hydrogen adsorption efficiency. In addition, the other end of the first porous branch pipe 22 is fixedly connected to the inner wall of the first tank body 2. This fixing method can be welding or flange thread connection to ensure that the first porous branch pipe 22 will not be displaced or deformed due to gas flow impact or temperature change during long-term operation. After being fixed to the inner wall of the first tank body 2, the first porous branch pipe 22 can dissipate heat faster through metal heat conduction, reducing the local temperature during the hydrogen absorption and heat release process and improving the hydrogen absorption capacity of the metal hydride.

[0045] Similarly, a second porous branch pipe is added inside the second tank body 3. The material of the second porous branch pipe is the same as that of the first porous branch pipe 22. One end of the second porous branch pipe is connected to the holes of the second porous pipe 31 to optimize the diffusion path of hydrogen during the hydrogen release process, improving the hydrogen release uniformity and rate. The other end of the second porous branch pipe is fixedly connected to the inner wall of the second tank body 3, using welding or bolt fixing methods to ensure the structural stability and optimize the gas flow stability during the hydrogen release process.

[0046] Through the optimization of this embodiment, the gas diffusion uniformity, heat management efficiency, structural stability, and overall operation reliability of the hydrogen purification device are further improved, making this device more suitable for high-efficiency hydrogen purification and long-term operation scenarios.

[0047] Embodiment 3 Based on Embodiment 2, this embodiment further optimizes the fluidity, diffusion uniformity, and hydrogen absorption and release efficiency of hydrogen in the system. By adding ultrasonic sources, arranging the branch pipes obliquely, and optimizing the wall thickness, the hydrogen purification efficiency is improved, the energy consumption is reduced, and the long-term stability of the system is enhanced.

[0048] As Figure 2 shown, in this embodiment, a first ultrasonic source 111 is installed on the inlet pipe 1. The ultrasonic source is fixed to the outer wall of the inlet pipe 1 and an industrial ultrasonic transducer with a working frequency of 20 - 40 kHz is selected to generate ultrasonic waves propagating along the direction of the inlet pipe 1 to the primary exhaust pipe 4. Further, a second ultrasonic source (not shown in the figure) is installed at the position where the gas connection pipe 5 is close to the second tank body 3. This ultrasonic source generates ultrasonic waves propagating along the direction of the gas connection pipe 5 to the outlet pipe 10.

[0049] Specifically, the present invention uses an industrial-grade piezoelectric ultrasonic transducer as the ultrasonic source. Its operating frequency is set at 20 - 40 kHz (adjustable), and the power range is 50 - 100 W, which can be adjusted according to the hydrogen gas flow rate and system requirements to optimize the diffusion and adsorption efficiency of hydrogen. The core vibration element of the ultrasonic transducer is piezoelectric ceramic (PZT, lead zirconate titanate), which has high-efficient acoustic energy conversion ability and can generate a stable ultrasonic field during the hydrogen absorption and desorption process of metal hydride to improve the hydrogen diffusion rate. The housing material is selected as stainless steel or aluminum alloy to enhance its corrosion resistance and durability, suitable for long-term operation in a hydrogen environment. The installation method of the ultrasonic source adopts bonding or flange fixing to ensure stable acoustic transmission characteristics in a high-pressure hydrogen environment without affecting the normal operation of the device. The ultrasonic transducer can be provided with a first ultrasonic source 111 and a second ultrasonic source on the intake pipe 1 and the gas connection pipe 5 respectively to provide ultrasonic assistance in different purification stages, improve the hydrogen diffusion uniformity, reduce the hydrogen absorption and desorption resistance, and optimize the hydrogen purification process.

[0050] In this embodiment, the first porous branch pipe 22 is arranged obliquely along the direction from the intake pipe 1 to the primary exhaust pipe 4, and the second porous branch pipe is arranged obliquely along the direction from the gas connection pipe 5 to the outlet pipe 10. The specific inclination angle is 10 o to 30 o .

[0051] In this embodiment, the middle pipe walls of the first porous branch pipe 22 and the second porous branch pipe become thinner, and the specific thickness is controlled at 0.2 - 0.5 mm (compared with the end thickness of 0.8 - 1.2 mm).

[0052] Through the optimization of this embodiment, the hydrogen diffusion rate, hydrogen absorption and desorption efficiency, and energy utilization rate are further improved, and the overall performance of the hydrogen purification device is optimized, making it more suitable for high-efficiency and low-energy-consumption hydrogen purification applications.

[0053] In summary, based on the dual-tank metal hydride hydrogen purification device, the present invention combines thermal management, ultrasonic-enhanced hydrogen absorption and desorption, optimized gas flow path, and precise flow and pressure control to achieve technological innovation with low energy consumption, high efficiency, stable structure, and strong hydrogen purification ability. Compared with traditional hydrogen purification methods (such as pressure swing adsorption, membrane separation, and cryogenic separation), the device of the present invention has a more compact structure, lower energy consumption, and higher hydrogen purity, and has broad application prospects in the fields of fuel cells, hydrogen energy storage and transportation, and industrial gas supply.

[0054] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included within the scope of protection of the present application.

Claims

1. A double-tank metal hydride hydrogen purification device, characterized in that: The invention comprises a first tank body, a second tank body, a primary exhaust pipe, a gas connecting pipe, a first liquid bath room, a second liquid bath room, a circulating liquid bath chamber, and a liquid connecting pipe. A first porous pipe and a first metal hydride are arranged in the first tank body, a second porous pipe and a second metal hydride are arranged in the second tank body, the primary exhaust pipe is connected to the first porous pipe, the gas connecting pipe is connected to the primary exhaust pipe and the second porous pipe, the first liquid bath room and the second liquid bath room respectively cover the first tank body and the second tank body, the first liquid bath room, the circulating liquid bath chamber, the second liquid bath room, and the liquid connecting pipe are connected in sequence to form a liquid pipeline.

2. The double-tank metal hydride hydrogen purification device according to claim 1, characterized in that: It also includes a first valve, a second valve, a third valve, and a fourth valve; the first valve is a one-way valve, and the first valve is arranged on the intake pipe; the second valve is a back pressure valve, and the second valve is arranged on the outside of the gas connecting pipe on the primary exhaust pipe; the third valve is a switching valve, and the third valve is arranged on the gas connecting pipe; the fourth valve is a back pressure valve, and the fourth valve is arranged on the outlet pipe.

3. The double-tank metal hydride hydrogen purification device according to claim 1, characterized in that: The invention also includes a liquid pump, which is arranged in the liquid pipeline to move the liquid in a direction from the first liquid passage chamber to the second liquid passage chamber.

4. The double-tank metal hydride hydrogen purification device according to claim 3, characterized in that: One end of the liquid connecting tube is connected to one end of the first liquid passage chamber close to the air inlet pipe, and the other end of the liquid connecting tube is connected to one end of the second liquid passage chamber close to the air outlet pipe.

5. The double-tank metal hydride hydrogen purification device according to claim 1, characterized in that: The invention also includes a heat pipe, wherein the heat pipe is multiple and the heat pipe is arranged between the first liquid-transferring bath room and the second liquid-transferring bath room.

6. The double-tank metal hydride hydrogen purification device according to claim 1, characterized in that: It also includes a heating system and a temperature measuring system. The heating system is used to heat the liquid in the circulating liquid bath chamber. The temperature measuring system includes at least one temperature sensor installed in the circulating liquid bath chamber to monitor the liquid temperature in real time.

7. The double-tank metal hydride hydrogen purification device according to claim 1, characterized in that: It also includes a flow control device and a pressure measuring device, and the flow control device and the pressure measuring device are arranged on the intake pipe.

8. The double-tank metal hydride hydrogen purification device according to claim 1, characterized in that: The first porous branch pipe is also included. The first porous branch pipe is arranged in the first tank body, and one end of the first porous branch pipe is connected to the holes of the first porous pipe.

9. The double-tank metal hydride hydrogen purification device according to claim 8, characterized in that: The other end of the first porous branch pipe is fixedly connected to the inner wall of the first tank body.

10. The double-tank metal hydride hydrogen purification device according to claim 1, characterized in that: It also includes a second porous branch pipe, which is arranged in the second tank body, and one end of the second porous branch pipe is connected to the holes of the second porous pipe.

11. The double-tank metal hydride hydrogen purification device according to claim 10, characterized in that: The other end of the second porous branch pipe is fixedly connected to the inner wall of the second tank body.

12. The double-tank metal hydride hydrogen purification device according to any one of claims 1 to 11, characterized in that: It also includes a first ultrasonic source, which is fixed on the intake pipe and generates ultrasonic waves along the direction from the intake pipe to the primary exhaust pipe.

13. The double-tank metal hydride hydrogen purification device according to claim 12, characterized in that: It also includes a second ultrasonic source, which is fixed on the gas connecting pipe close to the second tank body, and generates ultrasonic waves along the direction from the gas connecting pipe to the gas outlet pipe.

14. The double-tank metal hydride hydrogen purification device according to claim 13, characterized in that: The first porous branch pipe is inclined along the direction from the air inlet pipe to the primary exhaust pipe, and the second porous branch pipe is inclined along the direction from the gas connecting pipe to the air outlet pipe.

15. The double-tank metal hydride hydrogen purification device according to claim 14, characterized in that: The walls of the middle parts of the first porous branch pipe and the second porous branch pipe are thin.

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