A hydrogen production system using alkaline electrolysis of water

Abstract

The utility model provides a kind of hydrogen production system of alkaline electrolytic water, it is related to hydrogen energy technology field, including separation tank and gas outlet treatment system, separation tank is equipped with gas outlet, gas outlet is connected to gas outlet treatment system, the upper portion in separation tank is also equipped with sampling port, sampling port is connected to first gas concentration analyzer by sampling pipeline, sampling pipeline is equipped with first on-off valve.The utility model directly sets up sampling port in separation tank, and connects sampling port to first gas concentration analyzer by sampling pipeline, when system stops, first gas concentration analyzer can directly analyze the gas concentration in separation tank, to evaluate the risk of separation tank and hydrogen production system of alkaline electrolytic water, can find risk in time, to avoid the operation of nitrogen replacement for each system shutdown to ensure safety.

Description

Technical Field

[0001] This utility model relates to the field of hydrogen energy technology, and in particular to an alkaline water electrolysis hydrogen production system. Background Technology

[0002] Alkaline water electrolysis for hydrogen production is a mature method widely used in industrial production. In actual production, when an alkaline water electrolysis hydrogen production system experiences shutdown or restart, the hydrogen and oxygen products within the system can easily form an explosive mixture in a confined space. Therefore, after system shutdown, high-purity nitrogen is used to purge and replace the separator and pipelines to completely remove all hydrogen and oxygen from the system, preventing the formation of an explosive mixture in the confined space. This process is called nitrogen purging.

[0003] Nitrogen purging ensures production safety, but its disadvantages include consuming large amounts of nitrogen, wasting high-purity hydrogen and oxygen products remaining in the system during the purging process, and prolonged recovery periods for the purity of hydrogen and oxygen products due to residual nitrogen during system restart. Without nitrogen purging, existing detection instruments in hydrogen production systems cannot accurately detect gas purity during standby after shutdown, thus compromising production safety. Utility Model Content

[0004] The purpose of this invention is to provide an alkaline water electrolysis hydrogen production system that solves the technical problem of needing nitrogen replacement during system shutdown in the prior art.

[0005] This utility model provides an alkaline water electrolysis hydrogen production system, including a separation tank and a gas treatment system. The separation tank is provided with a gas outlet, which is connected to the gas treatment system. The upper part of the separation tank is also provided with a sampling port, which is connected to a first gas concentration analyzer through a sampling pipeline. The sampling pipeline is provided with a first on / off valve.

[0006] In an optional implementation, the sampling port is located between the highest point of the top of the separator and the horizontal centerline.

[0007] In an optional embodiment, the separation tank is further provided with a sampling extension tube, the upper end of which is located at the top of the separation tank, and the sampling extension tube extends to the lower part of the separation tank. The sampling port is located at the lower part of the sampling extension tube, and the sampling extension tube is connected to the sampling pipeline.

[0008] In an optional embodiment, the sampling port is located on the body of the separation tank.

[0009] In an optional embodiment, the sampling pipeline includes an inclined section that is inclined, with the end of the inclined section closer to the separation tank being lower than the end farther away from the separation tank.

[0010] In an optional implementation, the inclination angle of the inclined section of the sampling pipeline ranges from 5° to 90°.

[0011] In an optional implementation, the first gas concentration analyzer is connected to the exhaust gas treatment system via a detection pipeline, and the detection pipeline is equipped with a second on / off valve.

[0012] In an optional embodiment, the alkaline water electrolysis hydrogen production system further includes an electrolyzer, and a first gas concentration analyzer is connected to the electrolyzer via a detection pipeline, the detection pipeline being equipped with a third on / off valve.

[0013] In an optional implementation, the first gas concentration analyzer is a thermal conductivity gas analyzer or an in-situ laser gas analyzer.

[0014] In an optional implementation, the first gas concentration analyzer is an oxygen-hydrogen concentration analyzer or a hydrogen-oxygen concentration analyzer.

[0015] The alkaline water electrolysis hydrogen production system provided by this utility model has the following beneficial effects: This utility model directly sets a sampling port in the separation tank and connects the sampling port to a first gas concentration analyzer through a sampling pipeline. When the system is shut down, the first gas concentration analyzer can directly analyze the gas concentration in the separation tank, thereby assessing the risks of the separation tank and the alkaline water electrolysis hydrogen production system. Risks can be detected in time, thus avoiding the need for nitrogen purging every time the system is shut down to ensure safety. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 A schematic diagram of the alkaline water electrolysis hydrogen production system provided in Embodiment 1 of this utility model; Figure 2 A schematic diagram of the separator in the alkaline water electrolysis hydrogen production system provided in Embodiment 1 of this utility model; Figure 3 This is a partial schematic diagram of the alkaline water electrolysis hydrogen production system provided in Embodiment 1 of this utility model; Figure 4 This is a schematic diagram of the alkaline water electrolysis hydrogen production system provided in Embodiment 2 of this utility model; Figure 5 This is a schematic diagram of the alkaline water electrolysis hydrogen production system provided in Embodiment 3 of this utility model; Figure 6This is a schematic diagram of the separator in the alkaline water electrolysis hydrogen production system provided in Embodiment 3 of this utility model.

[0018] Icons: 100-Separation tank; 200-Sampling port; 210-Sampling extension tube; 300-First gas concentration analyzer; 410-First on / off valve; 420-Second on / off valve; 430-Third on / off valve; 500-Sampling pipeline; 510-Inclined section; 600-Electrolytic cell; 700-Gas exhaust treatment system. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0020] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0021] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0022] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0023] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0024] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0025] The following detailed description, in conjunction with the accompanying drawings, outlines some embodiments of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0026] Example 1 This embodiment provides an alkaline water electrolysis hydrogen production system, such as... Figures 1 to 3 As shown, the system includes a separation tank 100 and an exhaust gas treatment system 700. The separation tank 100 is provided with an exhaust gas outlet, which is connected to the exhaust gas treatment system 700. The upper part of the separation tank 100 is also provided with a sampling port 200, which is connected to a first gas concentration analyzer 300 through a sampling pipeline 500. The sampling pipeline 500 is provided with a first on / off valve 410.

[0027] in, Figure 1 This is a schematic diagram of the alkaline water electrolysis hydrogen production system provided in Embodiment 1 of this utility model. Figure 2 This is a schematic diagram of the separator 100 in the alkaline water electrolysis hydrogen production system provided in Embodiment 1 of this utility model. Figure 3 This is a partial schematic diagram of the alkaline water electrolysis hydrogen production system provided in Embodiment 1 of this utility model. Figure 3 Only the relevant parts of the connection between the first gas concentration analyzer 300 and the separator 100 are shown.

[0028] In this embodiment, a sampling port 200 is directly set inside the separation tank 100, and the sampling port 200 is connected to the first gas concentration analyzer 300 through the sampling pipeline 500. When the system is shut down, the first gas concentration analyzer 300 can directly analyze the gas concentration inside the separation tank 100, thereby assessing the risks of the separation tank 100 and the alkaline water electrolysis hydrogen production system. Risks can be detected in time, thus avoiding the need for nitrogen purging every time the system is shut down to ensure safety.

[0029] After the alkaline water electrolysis hydrogen production system is shut down, it enters a standby state. During standby, many factors can affect the gas distribution within the system and create safety hazards. Taking oxygen-to-hydrogen (HTO) as an example, system statistics show that the low-current operation phase causes an increase in HTO content. After shutdown, hydrogen produced by the electrolysis reaction current also enters the oxygen side, forming HTO. Hydrogen remaining in the dead zone within the electrolyzer 600 gradually diffuses to the oxygen side through the diaphragm, also forming HTO. After shutdown, hydrogen dissolved in the alkaline solution diffuses and precipitates through the connecting pipes between the separators 100, forming HTO. The above only lists some of the possible reasons for the increase in HTO during system shutdown. In particular, the HTO formed by the diffusion and precipitation of hydrogen dissolved in the alkaline solution through the connecting pipes between the separators 100 after shutdown can directly enter the oxygen environment of the oxygen-side separator 100, leading to an increase in the HTO concentration within separator 100, potentially causing safety hazards.

[0030] Existing alkaline water electrolysis hydrogen production systems are equipped with oxygen-hydrogen concentration analyzers, and these analyzers are installed at both the outlet of the electrolyzer 600 and the separation outlet of the gas treatment system 700. However, these existing oxygen-hydrogen concentration analyzers are designed for production conditions and can only perform detection during production. Specifically, for the oxygen-hydrogen concentration analyzer at the separation outlet of the gas treatment system 700, after the system is shut down, the gas in the oxygen-side separation tank 100 cannot flow normally to the detection point of the oxygen-hydrogen concentration analyzer as it would during production. This is because the gas treatment system 700 includes multiple modules, and the flow pipelines are subject to water seals. Therefore, the oxygen-hydrogen concentration analyzer in the gas treatment system 700 cannot detect the oxygen-hydrogen concentration when the system is shut down. The oxygen-hydrogen concentration analyzer at the outlet of electrolyzer 600 is mainly used to detect the hydrogen content in the oxygen of the gas at the outlet of electrolyzer 600 before it enters the separator 100. After the system is shut down, electrolyzer 600 stops producing hydrogen. In the absence of a gas source or with insufficient gas supply, the oxygen-hydrogen concentration analyzer at the outlet of electrolyzer 600 cannot be put into use. Furthermore, the oxygen-hydrogen concentration analyzer at the outlet of electrolyzer 600 cannot detect the hydrogen concentration in the oxygen inside the separator 100.

[0031] The alkaline water electrolysis hydrogen production system provided in this embodiment has a sampling port 200 directly set in the separation tank 100 and is equipped with a first on / off valve 410 to control the on / off of the sampling pipeline 500. It can independently detect the hydrogen concentration in oxygen in the separation tank 100 when the system is shut down, without the need for major modifications to the existing equipment and pipelines.

[0032] In this embodiment, as Figure 2As shown, the separation tank 100 is also provided with a sampling extension tube 210. The upper end of the sampling extension tube 210 is located at the top of the separation tank 100, and the sampling extension tube 210 extends to the lower part of the separation tank 100. The sampling port 200 is located at the lower part of the sampling extension tube 210. The sampling extension tube 210 is connected to the sampling pipeline 500. With this arrangement, the sampling port 200 can be located between the highest point of the top of the separation tank 100 and the horizontal central axis. Figure 2 This is a side sectional view of the separator 100 to show the positional relationship between the sampling extension tube 210, the sampling port 200, and the separator 100.

[0033] The sampling port 200 can be extended downwards from the top of the separator 100 by means of the sampling extension tube 210. Inside the separator 100, due to the light weight of hydrogen, some hydrogen may separate from the oxygen and float to the top of the internal space after the separator reaches a steady state. If the sampling point is set directly above the separator 100, the initial sample gas may have an excessively high hydrogen content, making it impossible to accurately detect the hydrogen content in the oxygen and leading to system misjudgment. Extending the sampling port 200 downwards from the top of the separator 100 by means of the sampling extension tube 210 avoids areas with high hydrogen content, thus ensuring accurate detection of the hydrogen content in the oxygen.

[0034] like Figure 3 As shown, in this embodiment, the sampling pipeline 500 includes an inclined section 510, with the end of the inclined section 510 near the separation tank 100 being lower than the end away from the separation tank 100. The temperature inside the separation tank 100 is high, and the gas inside the separation tank 100 contains a large amount of water vapor. If the first gas concentration analyzer 300 directly detects gas with a high water vapor content for an extended period, it is prone to failure. For example, in some models of gas concentration analyzers, prolonged testing with gas containing a high water vapor content accelerates the failure of the color-changing gel on the analyzer panel. However, in this embodiment, because the end of the inclined section 510 near the separation tank 100 is lower than the end away from the separation tank 100, the inclined section 510 in the sampling pipeline 500 can reduce the gas flow rate and achieve cooling through pipeline heat dissipation. As the gas cools, water vapor condenses and moves away from the first gas concentration analyzer 300 along with the inclined section 510, thereby avoiding affecting the service life of the first gas concentration analyzer 300.

[0035] Preferably, the inclination angle of the inclined section 510 of the sampling pipeline 500 is in the range of 5° to 90°, which can be selected according to the specific installation space conditions. When the inclination angle is less than this range, it is easy to lead to insufficient water vapor condensation effect.

[0036] In this embodiment, as Figure 1As shown, the first gas concentration analyzer 300 is connected to the exhaust gas treatment system 700 via a detection pipeline, which is equipped with a second on / off valve 420. In this case, the first gas concentration analyzer 300 can directly utilize the gas concentration analyzer already configured in the exhaust gas treatment system 700. It only requires connecting the existing gas concentration analyzer to the sampling port 200 of the separator 100 via a sampling pipeline 500. The gas source for the first gas concentration analyzer 300 is controlled by the first on / off valve 410 and the second on / off valve 420. During normal system operation, the first on / off valve 410 is completely closed, and during shutdown, the second on / off valve 420 is completely closed, thus enabling the analysis of gas concentrations under both conditions using a single gas concentration analyzer.

[0037] In this embodiment, the detection of hydrogen concentration in oxygen is used as an example for explanation. In this case, the first gas concentration analyzer 300 is an oxygen-hydrogen concentration analyzer. When applied to detect oxygen concentration in hydrogen, the first gas concentration analyzer 300 is a hydrogen-oxygen concentration analyzer.

[0038] Example 2 This embodiment also provides an alkaline water electrolysis hydrogen production system, such as... Figure 4 As shown, the main technical solution of Embodiment 2 is the same as that of Embodiment 1, except for the specific settings of the first gas concentration analyzer 300.

[0039] Figure 4 This is a schematic diagram of the alkaline water electrolysis hydrogen production system provided in Embodiment 2 of this utility model, as shown below. Figure 4 As shown, the alkaline water electrolysis hydrogen production system includes an electrolyzer 600. A first gas concentration analyzer 300 is connected to the electrolyzer 600 via a detection pipeline, which is equipped with a third on / off valve 430. In this case, the first gas concentration analyzer 300 can directly utilize the gas concentration analyzer at the outlet of the electrolyzer 600. Only an additional sampling pipeline 500 needs to be connected to the sampling port 200 of the separator 100. The gas source for the first gas concentration analyzer 300 is controlled by the first on / off valve 410 and the third on / off valve 430. During normal system operation, the first on / off valve 410 is completely closed, and during shutdown, the third on / off valve 430 is completely closed, thus enabling the analysis of gas concentrations under both conditions using a single gas concentration analyzer.

[0040] Example 3 This embodiment also provides an alkaline water electrolysis hydrogen production system, such as... Figure 5 and Figure 6 As shown, the main technical solution of Embodiment 3 is the same as that of Embodiment 1, except that the specific settings of the first gas concentration analyzer 300 and the sampling port 200 are different.

[0041] like Figure 5As shown, the first gas concentration analyzer 300 is an independent gas concentration analyzer, added in addition to the gas concentration analyzers at the outlet of the electrolytic cell 600 and the separation outlet of the gas treatment system 700 in the existing system. The relevant structures of the gas concentration analyzers at the outlet of the electrolytic cell 600 and the separation outlet of the gas treatment system 700 in the existing system are described in... Figure 5 Not shown in the image.

[0042] In this embodiment, the first gas concentration analyzer 300 can be a thermal conductivity gas analyzer or an in-situ laser gas analyzer.

[0043] Figure 6 This is a side sectional view of the separation tank 100 in this embodiment, illustrating the positional relationship between the sampling port 200 and the separation tank 100. Figure 6 As shown, the sampling port 200 is directly located on the body of the separator 100, and the sampling port 200 is situated between the highest point of the top of the separator 100 and the horizontal central axis, avoiding the highest point of the top of the separator 100. In this way, the sampling port 200 can also avoid areas with high hydrogen content, thereby accurately detecting the hydrogen content in oxygen.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. An alkaline water electrolysis hydrogen production system, characterized in that, It includes a separation tank (100) and an exhaust gas treatment system (700). The separation tank (100) is provided with an exhaust gas outlet, which is connected to the exhaust gas treatment system (700). The upper part of the separation tank (100) is also provided with a sampling port (200). The sampling port (200) is connected to a first gas concentration analyzer (300) through a sampling pipeline (500). The sampling pipeline (500) is provided with a first on / off valve (410).

2. The alkaline water electrolysis hydrogen production system according to claim 1, characterized in that, The sampling port (200) is located between the highest point of the top of the separation tank (100) and the horizontal central axis.

3. The alkaline water electrolysis hydrogen production system according to claim 2, characterized in that, The separation tank (100) is also provided with a sampling extension tube (210). The upper end of the sampling extension tube (210) is located at the top of the separation tank (100), and the sampling extension tube (210) extends to the lower part of the separation tank (100). The sampling port (200) is located at the lower part of the sampling extension tube (210), and the sampling extension tube (210) is connected to the sampling pipeline (500).

4. The alkaline water electrolysis hydrogen production system according to claim 2, characterized in that, The sampling port (200) is located on the body of the separation tank (100).

5. The alkaline water electrolysis hydrogen production system according to claim 1, characterized in that, The sampling pipeline (500) includes an inclined section (510) that is inclined, with the end of the inclined section (510) near the separation tank (100) being lower than the end away from the separation tank (100).

6. The alkaline water electrolysis hydrogen production system according to claim 5, characterized in that, The inclination angle of the inclined section (510) of the sampling pipeline (500) ranges from 5° to 90°.

7. The alkaline water electrolysis hydrogen production system according to claim 1, characterized in that, The first gas concentration analyzer (300) is connected to the gas treatment system (700) through a detection pipeline, and the detection pipeline is equipped with a second on / off valve (420).

8. The alkaline water electrolysis hydrogen production system according to claim 1, characterized in that, The alkaline water electrolysis hydrogen production system also includes an electrolyzer (600), and the first gas concentration analyzer (300) is connected to the electrolyzer (600) through a detection pipeline, which is equipped with a third on / off valve (430).

9. The alkaline water electrolysis hydrogen production system according to claim 1, characterized in that, The first gas concentration analyzer (300) is a thermal conductivity gas analyzer or an in-situ laser gas analyzer.

10. The alkaline water electrolysis hydrogen production system according to claim 1, characterized in that, The first gas concentration analyzer (300) is an oxygen-hydrogen concentration analyzer or a hydrogen-oxygen concentration analyzer.

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