Water tank structure and electrolytic hydrogen production device

Abstract

A water tank structure comprises a tank body and a filter screen structure. The tank body is sequentially provided with a gas collection area, a water flow stabilization area, a filtering area and a water quality purification area along the direction of gravity. The tank body is provided with an air inlet and an air outlet corresponding to the gas collection area, a first water inlet corresponding to the water flow stabilization area and a water outlet corresponding to the water quality purification area. The filter screen structure is used to reduce water fluctuation in the water flow stabilization area. The water tank structure can effectively alleviate the disturbance of hydraulic impact and improve the accuracy of measurement. The application also relates to an electrolytic hydrogen production device.

Description

Technical Field

[0001] This invention relates to the field of hydrogen electrolysis technology, and particularly to a water tank structure and an electrolysis hydrogen production device. Background Technology

[0002] Hydrogen, as a substitute for traditional fossil fuels, has been vigorously promoted and supported by the government in recent years. Electrolysis for producing green hydrogen has been widely discussed, and numerous domestic and international companies have already entered the electrolysis hydrogen production industry. Compared to the mature alkaline hydrogen production process (ALK), PEM electrolysis hydrogen production technology is widely used in power plants, electronics factories, the transportation industry, fuel cells, and other new energy alternatives due to its advantages such as pollution-free electrolysis of pure water, adaptability to the fluctuations in renewable energy power, hydrogen purity greater than 99.999%, and small footprint.

[0003] The PEM electrolysis hydrogen production process mainly includes equipment such as an electrolyzer, a pure water tank, a heat exchanger, a circulating pump, a purifier, a separator, and a dryer. The electrolyte in the PEM electrolyzer is pure water. Water from the pure water tank enters the electrolyzer via a circulating pump for electrolysis. The oxygen produced during electrolysis and the remaining water return to the pure water tank for gas-liquid separation. The pure water tank, also known as the oxygen-water separator, is equipped with a level gauge, temperature sensor, circulating pump inlet, water inlet, conductivity meter, drain outlet, electrolyzer return outlet, air filter, hydrogen detector, and fan, making it a multi-functional system.

[0004] The hydrogen permeation rate in domestic and some foreign PEM electrolyzers has exceeded the lower explosive limit of hydrogen (4% VOL). A fan must be installed on the side of the oxygen-water separator (pure water tank) to dilute the hydrogen before discharging it, so as to ensure that there is no explosive environment inside the oxygen-water separator (pure water tank).

[0005] When the water level in the tank drops, the water supply valve is opened to replenish pure water. The water quality of the incoming water is detected by a conductivity meter and the water quality in the tank is monitored in real time. When the resistivity is lower than 1 MΩ·cm, the system stops. If the resistivity is lower than 10 MΩ·cm for a long time, the life of the electrolytic cell will be greatly reduced.

[0006] The pure water tanks used in PEM hydrogen production systems currently on the market have the following defects:

[0007] First, the resistivity of the pure water in the tank decreases: a fan is used to draw air into the pure water tank to remove hydrogen /

[0008] Oxygen is diluted and discharged. The fan draws air into the pure water tank, causing the resistivity of the pure water to drop rapidly, making it impossible to reach the resistivity required for electrolysis in the electrolytic cell (>10 MΩ·cm).

[0009] Secondly, fluctuations in the water tank level and inaccurate feedback values ​​from the level gauge: the airflow from the fan can cause inaccurate level gauge readings inside the tank, the impact of water returning to the pure water tank can also affect the accurate measurement of the level gauge inside the tank, and the force of the circulating pump can also affect the level gauge measurement. Summary of the Invention

[0010] In view of this, the present invention provides a water tank structure that can effectively mitigate the disturbance of hydraulic impact and improve the accuracy of measurement.

[0011] A water tank structure includes a tank body and a filter structure. The tank body is provided with a gas collection zone, a water flow stabilization zone, a filtration zone and a water purification zone in sequence along the direction of gravity. The tank body is provided with an air inlet and an exhaust outlet corresponding to the gas collection zone, a first water inlet corresponding to the water flow stabilization zone and a water outlet corresponding to the water purification zone. The filter structure is used to reduce water fluctuations in the water flow stabilization zone.

[0012] In an embodiment of the present invention, a portion of the filter structure is located in the water flow stabilization zone, and another portion of the filter structure is located in the gas collection zone.

[0013] In an embodiment of the present invention, the above-mentioned water tank structure further includes a flow guide, the flow guide is connected to the tank body, the flow guide channel inside the flow guide is connected to the first water inlet, and the flow guide is provided with a second water inlet connected to the flow guide channel.

[0014] In an embodiment of the present invention, the above-described filter structure is disposed in the flow channel.

[0015] In an embodiment of the present invention, the aforementioned housing forms a gas guiding channel communicating with the gas collection area, and the exhaust port is provided corresponding to the gas guiding channel. Gas in the gas collection area is discharged from the exhaust port after passing through the gas guiding channel.

[0016] In an embodiment of the present invention, the inner wall of the aforementioned box located in the gas collection area is connected to a partition, and the partition and the inner wall of the water tank structure enclose the gas guiding channel.

[0017] In an embodiment of the present invention, the outer wall of the aforementioned housing is provided with an air guide portion, the air guide channel is formed inside the air guide portion, and the exhaust port is disposed on the air guide portion.

[0018] In an embodiment of the present invention, the above-mentioned water tank structure further includes an air filter, which is disposed corresponding to the air inlet.

[0019] In an embodiment of the present invention, the above-mentioned housing is further provided with a detection port communicating with the air guide channel, and the water tank structure further includes a detector, which is correspondingly set at the detection port.

[0020] In an embodiment of the present invention, the detector described above is used to detect the hydrogen concentration in the gas delivery channel.

[0021] In an embodiment of the present invention, the above-mentioned water tank structure further includes a fan, which is arranged corresponding to the exhaust port and is used to discharge the gas in the air guide channel.

[0022] In an embodiment of the present invention, the aforementioned housing includes a side wall for mounting a detection instrument. The side wall is provided with a vent hole, a liquid passage hole, and a liquid level detection hole arranged along the direction of gravity. The vent hole connects the liquid level detection hole and the gas collection area, and the liquid passage hole connects the liquid level detection hole and the water purification area. The water tank structure further includes a liquid level detector for detecting the liquid level inside the housing, and the liquid level detector is at least partially installed in the liquid level detection hole.

[0023] In an embodiment of the present invention, the aforementioned housing includes a side wall for mounting a testing instrument. The side wall is provided with a liquid replenishment hole, a liquid inlet hole, and a conductivity detection hole. The liquid replenishment hole communicates with the conductivity detection hole, and the liquid inlet hole communicates with the conductivity detection hole and the water purification zone. The water tank structure also includes a conductivity detector for detecting the resistivity value of the liquid. The conductivity detector is at least partially installed in the conductivity detection hole.

[0024] In an embodiment of the present invention, the above-mentioned water tank structure further includes a filter element for purifying water quality. The filter element is disposed in the filtration zone, and the water flow in the water flow stabilization zone enters the water quality purification zone after passing through the filter element.

[0025] In an embodiment of the present invention, the water tank structure further includes a filter support plate for purifying water quality, wherein at least one end of the filter support plate is fixed to the inner wall of the tank body, and the filter element is laid on the filter support plate.

[0026] The present invention also relates to an electrolytic hydrogen production apparatus, including the water tank structure described above.

[0027] The water tank structure of this invention is divided into a gas collection zone, a water flow stabilization zone, a filtration zone, and a water purification zone along the direction of gravity. This design allows the electrolyzed pure water to be buffered and reduced by the filter structure after entering the water flow stabilization zone, effectively mitigating the disturbance of hydraulic impact and improving measurement accuracy. Then, the pure water passes through the filtration zone under the action of gravity and enters the water purification zone. After passing through the filtration zone, the water quality is purified, which helps to improve the resistivity of the pure water, for example, the resistivity of the filtered pure water is greater than 10 MΩ·cm. Since the water purification zone is not affected by the water flow fluctuations and wind in the water flow stabilization zone, it can solve the problem of the pure water quality declining sharply due to wind. Attached Figure Description

[0028] Figure 1 This is a cross-sectional view of the water tank structure along the direction of gravity according to the first embodiment of this application.

[0029] Figure 2 This is a cross-sectional view of the sidewall along the gravity direction of the first embodiment of this application.

[0030] Figure 3 This is a cross-sectional view of the water tank structure in the first embodiment of this application along the horizontal direction.

[0031] Figure 4 This is a cross-sectional view of the water tank structure along the direction of gravity according to the second embodiment of this application. Detailed Implementation

[0032] The following specific embodiments illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification.

[0033] In the following description, reference is made to the accompanying drawings, which illustrate several embodiments of the present application. It should be understood that other embodiments may also be used, and changes in mechanical composition, structure, electrical and operational aspects may be made without departing from the spirit and scope of the present application. The following detailed description should not be considered limiting, and the terminology used herein is for describing particular embodiments only and is not intended to limit the present application.

[0034] Although the terms first, second, etc., are used in some instances to describe various elements herein, these elements should not be limited by these terms. These terms are only used to distinguish one element from another.

[0035] Furthermore, as used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context indicates otherwise. It should be further understood that the terms “comprising,” “including,” indicate the presence of a feature, step, operation, element, component, item, kind, and / or group, but do not exclude the presence, occurrence, or addition of one or more other features, steps, operations, elements, components, items, kinds, and / or groups. The terms “or” and “and / or” as used herein are interpreted as inclusive, or mean any one or any combination thereof. Thus, “A, B, or C” or “A, B, and / or C” means “any one of: A; B; C; A and B; A and C; B and C; A, B, and C.” Exceptions to this definition arise only when combinations of elements, functions, steps, or operations are inherently mutually exclusive in some way.

[0036] First Embodiment

[0037] Figure 1This is a cross-sectional view of the water tank structure according to the first embodiment of this application along the direction of gravity, as shown below. Figure 1 As shown, the water tank structure includes a tank body 11 and a filter structure 12. The tank body 11 is provided with a gas collection area 11a, a water flow stabilization area 11b, a filtration area 11c, and a water purification area 11d in sequence along the direction of gravity. The tank body 11 is provided with an air inlet 101 and an exhaust outlet 102 corresponding to the gas collection area 11a, a first water inlet 103 corresponding to the water flow stabilization area 11b, and a water outlet 104 corresponding to the water purification area 11d. The filter structure 12 is used to reduce water fluctuations in the water flow stabilization area 11b. The water tank structure of this embodiment is applied in a PEM electrolysis hydrogen production device. The PEM electrolysis hydrogen production device draws pure water from the outlet 104 of the tank 11 to the electrolysis cell for electrolysis via a water pump. The oxygen generated by electrolysis and the remaining pure water enter the water flow stabilization zone 11b of the tank 11 from the first inlet 103. The water surface fluctuation can be reduced by the blocking and buffering of the filter structure 12. The hydrogen dissolved in the pure water will be released into the gas collection zone 11a and mixed with oxygen. The gas in the gas collection zone 11a can be discharged from the exhaust port 102, and the outside air can enter the gas collection zone 11a from the air inlet 101 to dilute the hydrogen concentration and prevent the hydrogen concentration in the oxygen from exceeding the explosive range (4% to 75% vol).

[0038] The tank structure of this application is divided into a gas collection zone 11a, a water flow stabilization zone 11b, a filtration zone 11c, and a water purification zone 11d along the direction of gravity. This design allows the electrolyzed pure water to be blocked and buffered by the filter structure 12 after entering the water flow stabilization zone 11b, reducing water surface fluctuations and effectively mitigating the disturbance of hydraulic impact, thus improving measurement accuracy. Then, under the action of gravity, the pure water passes through the filtration zone 11c and enters the water purification zone 11d. After passing through the filtration zone 11c, the water quality is purified, which is beneficial to improving the resistivity of the pure water. For example, the resistivity of the filtered pure water is greater than 10 MΩ·cm. Since the water purification zone 11d is not affected by the water flow fluctuations and wind in the water flow stabilization zone 11b, it can solve the problem of the pure water quality declining sharply due to wind.

[0039] Optionally, such as Figure 1 As shown, part of the filter structure 12 is located in the water flow stabilization zone 11b, and another part of the filter structure 12 is located in the gas collection zone 11a. In this embodiment, 1 / 2 to 2 / 3 of the filter structure 12 along the direction of gravity is submerged in water, and the other part is located in the gas collection zone 11a, which can effectively mitigate the impact of water flow and the disturbance of wind on the water flow.

[0040] Optionally, such as Figure 1As shown, the filter structure 12 includes a central crossbeam and multiple filter screens arranged at intervals, with each filter screen connected to the central crossbeam. In this embodiment, the filter structure 12 is composed of several filter screens made of 316L stainless steel or PP material, with a filter screen pore size of 3-10mm, but not limited to this.

[0041] Optionally, such as Figure 1 As shown, a handhole 112 is connected to the side wall 114 of the housing 11, and a first water inlet 103 passes through the handhole 112. The position of the first water inlet 103 is designed to be level with the highest point of the water level inside the housing 11. In this embodiment, the handhole 112 is detachably screwed to the side wall 114 of the housing 11 by threads, which facilitates the removal of the handhole 112 and cleaning of the inside of the housing 11, or replacement of components.

[0042] Optionally, the diameter of the hand hole 112 is greater than 120 mm to facilitate the installation of the filter structure 12 into the housing 11.

[0043] Optionally, the number of first inlets 103 is determined according to the process design of the PEM electrolysis hydrogen production unit, with several first inlets 103 set for several return water lines.

[0044] Optionally, such as Figure 1 As shown, the housing 11 has an air guiding channel 105 communicating with the gas collection area 11a, and an exhaust port 102 is provided corresponding to the air guiding channel 105. The gas in the gas collection area 11a is discharged from the exhaust port 102 after passing through the air guiding channel 105. In this embodiment, the independent air guiding channel 105 is provided in the housing 11, which can reduce the impact of airflow on water surface fluctuations during exhaust.

[0045] Optionally, such as Figure 1 As shown, the inner wall of the box 11 located in the gas collection area 11a is connected to a partition 113, and the partition 113 and the inner wall of the water tank structure enclose the gas guiding channel 105.

[0046] Optionally, the gas collection area 11a occupies more than half of the internal volume of the entire container 11, which facilitates better dilution of hydrogen and reduces disturbance to the water surface.

[0047] Optionally, such as Figure 1 As shown, the water tank structure also includes an air filter 13, which is correspondingly arranged with the air inlet 101. In this embodiment, the air filter 13 is used to remove impurities and dust from the air, reducing contamination of the pure water inside the tank 11; the filtration capacity of the air filter 13 should be greater than 500 times the maximum hydrogen permeation capacity of the electrolyzer, to fully dilute the oxygen generated by the electrolyzer and the amount of hydrogen permeated.

[0048] Optionally, the tank body 11 is also provided with a detection port 106 that communicates with the air guide channel 105, and the water tank structure also includes a detector 14, which is correspondingly set at the detection port 106.

[0049] Optionally, the detector 14 is used to detect the hydrogen concentration in the gas delivery channel 105; the detection range is 0–100% LEL. Since the gas delivery channel 105 serves as a channel for diluted gas, it facilitates accurate detection of the hydrogen content in the diluted gas by the detector 14. Because the diluted gas enters the gas delivery channel 105 from the gas collection area 11a, the detector 14 can detect the hydrogen concentration in the gas delivery channel 105, thus improving the accuracy of the detector 14.

[0050] Optionally, such as Figure 1 As shown, the water tank structure also includes a blower 15, which is correspondingly arranged with the exhaust port 102. The blower 15 is used to discharge the gas in the gas guide channel 105. In this embodiment, the air volume of the blower 15 should be greater than 300 times the maximum hydrogen permeation capacity of the electrolyzer.

[0051] Optionally, both the detector 14 and the fan 15 are explosion-proof devices. The model of the fan 15 and the number and model of the air filter 13 are determined based on the amount of hydrogen permeation and the air filtration capacity. The detector 14 has a detection range of 0-100% LEL, an alarm value of 10% LEL, and a shutdown value of 15% LEL.

[0052] Alternatively, in order to ensure that the hydrogen is completely diluted, the inlet 101 and the outlet 102 should be set separately to avoid short-circuiting. For example, the inlet 101 can be set on the side away from the gas guide channel 105, or the inlet 101 and the outlet 102 can be designed on the two sides of the housing 11 respectively.

[0053] Optionally, Figure 2 This is a cross-sectional view of the sidewall along the gravity direction of the first embodiment of this application, as shown below. Figure 2 As shown, the housing 11 includes a side wall 114 for mounting the detector 14. The side wall 114 has a vent 107, a liquid passage 108, and a liquid level detection hole 109 arranged along the direction of gravity. The vent 107 connects the liquid level detection hole 109 to the gas collection area 11a, and the liquid passage 108 connects the liquid level detection hole 109 to the water purification area 11d. The tank structure also includes a liquid level detector 16 for detecting the liquid level inside the housing 11. The liquid level detector 16 is at least partially installed in the liquid level detection hole 109. In this embodiment, the liquid passage 108 is located at the bottom of the water purification area 11d. Pure water in the water purification area 11d enters the liquid level detection hole 109 through the liquid passage 108. The vent 107 connects to the gas collection area 11a to maintain airflow in the liquid level detection hole 109.

[0054] Optionally, the thickness of the sidewall 114 is greater than 60 mm. The vent hole 107, the liquid passage hole 108 and the liquid level detection hole 109 are formed by drilling holes inside the sidewall 114. The liquid level detector 16 is installed in the liquid level detection hole 109, and the sidewall 114 protects the liquid level detector 16.

[0055] Optionally, Figure 3 This is a cross-sectional view of the water tank structure of the first embodiment of this application along the horizontal direction, as shown below. Figure 3 As shown, the side wall 114 is provided with a replenishment hole 201, an inlet hole 202, and a conductivity detection hole 203. The replenishment hole 201 is connected to the conductivity detection hole 203, and the inlet hole 202 is connected to the conductivity detection hole 203 and the water purification zone 11d. The water tank structure also includes a conductivity detector 17 for detecting the liquid resistivity value. The conductivity detector 17 is at least partially installed in the conductivity detection hole 203. When the pure water in the tank 11 is insufficient, pure water is discharged into the water purification zone 11d from the replenishment hole 201, the conductivity detection hole 203, and the inlet hole 202. During this process, the conductivity detector 17 can detect the quality of the replenished water. When the pure water in the tank 11 is sufficient, the conductivity detector 17 can detect the quality of the pure water in the water purification zone 11d. That is to say, this application only needs to install one conductivity detector 17, that is, one detector has two uses, which can reduce costs.

[0056] The liquid level detector 16 and conductivity detector 17 of this application are installed by drilling holes in the side wall 114, which reduces the influence of water fluctuations on the detectors and ensures the accuracy and stability of the detector measurements.

[0057] Optionally, such as Figure 1 As shown, the water tank structure also includes a filter element 18 for purifying water quality. The filter element 18 is disposed in the filtration zone 11c, and the water flowing from the water flow stabilization zone 11b enters the water purification zone 11d after passing through the filter element 18. After being filtered by the filter element 18, the resistivity of the pure water entering the water purification zone 11d is guaranteed to be greater than 10 MΩ·cm. When the conductivity detector 17 detects that the pure water quality in the water purification zone 11d is substandard for an extended period, the problem can be solved by replacing the filter element 18. Specifically, the manhole 112 is removed from the tank body 11, and then the filter element 18 is replaced. In this embodiment, the filter screen structure 12 is disposed on the filter element 18.

[0058] Optionally, the filter element 18 is located at the midpoint between the sum of the water levels in the stable water flow zone 11b and the water purification zone 11d, and its height along the direction of gravity is greater than or equal to 60 mm.

[0059] Optionally, such as Figure 1As shown, the water tank structure also includes a filter support plate 19 for purifying water. At least one end of the filter support plate 19 is fixed to the inner wall of the tank body 11, and the filter support plate 19 is laid on the tank body 11. In this embodiment, the filter support plate 19 is, for example, a stainless steel 316L or PP material filter screen with a pore size of 3-10mm to ensure that pure water can pass through smoothly by gravity and to provide support.

[0060] Optionally, when the filter support plate 19 is not installed inside the housing 11, the filter element 18 can be fixed to the inner wall of the housing 11.

[0061] Optionally, the filter element 18 may be, for example, a nylon bag containing polishing resin, with a pore size of less than 5 μm and a particle size of polishing resin greater than 500 μm.

[0062] Optionally, the water tank structure also includes instruments such as temperature sensors and interfaces such as water tank drain outlets. These are less affected by the structural design of the tank body 11. The temperature sensors and other instruments, as well as the water tank drain outlets, are not shown in the attached drawings. They can be connected through openings on any side wall 114 or bottom of the tank body 11, as long as accurate measurement is ensured.

[0063] Optionally, the water tank structure of this application can be used not only in PEM electrolysis hydrogen production devices, but also in other devices that achieve the same function.

[0064] Optionally, the tank 11 is a cube or cuboid with a volume of 20L-150L, ​​and is made of PP plastic through processing and welding. The tank 11 is small in size and belongs to a highly integrated small water tank.

[0065] The detector in the water tank structure of this application has stable measurement, a safe internal environment without explosion, and can purify pure water in real time, realizing multiple functions of the water tank.

[0066] Second Embodiment

[0067] Figure 4 This is a cross-sectional view of the water tank structure along the direction of gravity according to the second embodiment of this application, as shown below. Figure 4 As shown, the water tank structure in this embodiment is largely the same as that in the first embodiment, except that it also includes a flow guide 21. The flow guide 21 is connected to the tank body 11, and the flow channel 204 inside the flow guide 21 is connected to the first inlet 103. The flow guide 21 is provided with a second inlet 205 that is connected to the flow channel 204. Electrolyzed water discharged from the electrolytic cell enters the flow channel 204 through the second inlet 205 and finally enters the water flow stabilization zone 11b through the first inlet 103. The buffering effect of the flow guide 21 effectively reduces water surface fluctuations. In this embodiment, the flow guide 21 is threaded to the hand hole 112 for easy disassembly of the flow guide 21.

[0068] Optionally, the filter structure 12 is disposed in the flow channel 204, so that the pure water can further reduce water surface ripples after being blocked and buffered by the filter structure 12.

[0069] Optionally, in this embodiment, the outer wall of the housing 11 is provided with an air guide portion 115, an air guide channel 105 is formed inside the air guide portion 115, and an exhaust port 102 is provided in the air guide portion 115.

[0070] For other structural details regarding the water tank, please refer to the first embodiment; they will not be elaborated upon here.

[0071] Third Embodiment

[0072] This application also relates to an electrolytic hydrogen production apparatus, including the aforementioned water tank structure.

[0073] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.

Claims

1. A water tank structure, characterized in that, The system includes a housing and a filter structure. The housing is arranged along the direction of gravity as follows: a gas collection zone, a water flow stabilization zone, a filtration zone, and a water purification zone. The housing has an air inlet and an air outlet corresponding to the gas collection zone, a first water inlet corresponding to the water flow stabilization zone, and a water outlet corresponding to the water purification zone. The filter structure is used to reduce water fluctuations in the water flow stabilization zone. The filter structure is arranged such that one part of the filter structure is located in the water flow stabilization zone and the other part is located in the gas collection zone. Alternatively, the water tank structure may also include a flow guide connected to the housing. The flow guide channel within the flow guide is connected to the first water inlet, and the flow guide has a second water inlet connected to the flow guide channel. The filter structure is disposed in the flow guide channel.

2. The water tank structure as described in claim 1, characterized in that, The housing has a gas guiding channel that communicates with the gas collection area, and the exhaust port is provided corresponding to the gas guiding channel. The gas in the gas collection area is discharged from the exhaust port after passing through the gas guiding channel.

3. The water tank structure as described in claim 2, characterized in that, include: The inner wall of the box body located in the gas collection area is connected to a partition, and the partition and the inner wall of the water tank structure enclose the gas guiding channel. The outer wall of the housing is provided with an air guide section, the air guide channel is formed inside the air guide section, and the exhaust port is provided in the air guide section.

4. The water tank structure as described in claim 2, characterized in that, include: The water tank structure also includes an air filter, which is configured corresponding to the air inlet; The housing is also provided with a detection port that communicates with the air guide channel, and the water tank structure also includes a detector, which is set corresponding to the detection port; The detector is used to detect the hydrogen concentration in the gas delivery channel; The water tank structure also includes a fan, which is arranged corresponding to the exhaust port and is used to discharge the gas in the air guide channel.

5. The water tank structure as described in claim 1, characterized in that, The housing includes a side wall for mounting the testing instrument. The side wall is provided with a vent hole, a liquid passage hole, and a liquid level detection hole arranged along the direction of gravity. The vent hole connects the liquid level detection hole and the gas collection area, and the liquid passage hole connects the liquid level detection hole and the water purification area. The water tank structure also includes a liquid level detector for detecting the liquid level in the tank. The liquid level detector is at least partially installed in the liquid level detection hole.

6. The water tank structure as described in claim 1, characterized in that, The housing includes a side wall for mounting the testing instrument. The side wall is provided with a liquid replenishment hole, a liquid inlet hole, and a conductivity detection hole. The liquid replenishment hole is connected to the conductivity detection hole, and the liquid inlet hole is connected to the conductivity detection hole and the water purification area. The water tank structure also includes a conductivity detector for detecting the liquid resistivity value. The conductivity detector is at least partially installed in the conductivity detection hole.

7. The water tank structure as described in claim 1, characterized in that, include: The water tank structure also includes a filter element for purifying water quality. The filter element is disposed in the filtration zone, and the water flow in the water flow stabilization zone enters the water purification zone after passing through the filter element. The water tank structure also includes a filter support plate for purifying water quality. At least one end of the filter support plate is fixed to the inner wall of the tank body, and the filter element is laid on the filter support plate.

8. An electrolytic hydrogen production apparatus, characterized in that, Includes the water tank structure described in any one of claims 1 to 7.

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