Anode for preventing corrosion at the mouth of the flow channel of an alkaline electrolyzer

Abstract

The utility model provides a kind of polar plate for preventing the corrosion of alkaline electrolytic cell flow passage mouth, belong to electrolytic cell technical field, the polar plate includes lye outlet, lye inlet, the polar plate further includes: gasket, lye outlet is provided with lye outlet flow passage mouth, lye inlet is provided with lye inlet flow passage mouth, the gasket includes: lye outlet gasket and lye inlet gasket, lye outlet gasket matched with lye outlet flow passage mouth is installed on lye outlet flow passage mouth, lye inlet gasket matched with lye inlet flow passage mouth is installed on lye inlet flow passage mouth, insulate flow passage mouth and the contact of alkaline electrolyte in electrolytic cell.This application is matched with different shape specifications of gasket, install alkali-resistant, high-temperature-resistant, corrosion-resistant gasket in lye inlet and lye outlet of alkaline electrolytic cell flow passage, can effectively solve the problem of easy corrosion of flow passage mouth, improve the service life of alkaline electrolytic cell.

Description

Technical Field

[0001] This utility model relates to the field of electrolytic cell technology, specifically to an electrode plate for preventing corrosion at the flow channel opening of an alkaline electrolytic cell. Background Technology

[0002] In the alkaline water electrolysis hydrogen production process, 30wt% KOH is generally used as the electrolyte, the operating temperature is 80℃-90℃, and the catalyst is generally a nickel-based catalyst. The main electrode plate of the alkaline electrolyzer is made of steel. Because Fe is more reactive than Ni, the main electrode plate is prone to corrosion under high temperature and high concentration alkaline conditions. Therefore, it needs to be nickel-plated to achieve corrosion protection. The actual thickness of the nickel plating on the electrode plate mainly depends on the current density at that point. The current distribution is mainly caused by geometric factors such as the shape of the component, the position of the component relative to the anode, and the arrangement of the component on the electroplating rack. The current density is lower in the concave areas and the areas facing away from the anode because the distance between the cathode and the anode is longer, and the resistance to current flow is greater, so the plating layer in the concave areas is thinner. The water inlet and outlet of the electrode plate are concave, and the plating thickness at the water inlet and outlet is thinner than that at the flat surface.

[0003] Thinner areas of the coating are easily corroded by alkaline solutions, which may damage the structural integrity of the alkaline electrolyzer, affecting its stability and safety; it may also lead to a decline in the performance of the electrolyzer, such as a decrease in conductivity and a reduction in hydrogen production. Utility Model Content

[0004] To address the shortcomings of existing technologies, this invention provides an electrode plate for preventing corrosion at the flow channel opening of an alkaline electrolytic cell.

[0005] The present invention adopts the following technical solution.

[0006] This utility model discloses an electrode plate for preventing corrosion of the flow channel opening in an alkaline electrolytic cell, comprising an alkaline solution outlet and an alkaline solution inlet. The electrode plate further includes a gasket. The alkaline solution outlet is provided with an alkaline solution outlet flow channel, and the alkaline solution inlet is provided with an alkaline solution inlet flow channel. The gasket includes an alkaline solution outlet gasket and an alkaline solution inlet gasket. An alkaline solution outlet gasket matching the alkaline solution outlet flow channel is installed on the alkaline solution outlet flow channel, and an alkaline solution inlet gasket matching the alkaline solution inlet flow channel is installed on the alkaline solution inlet flow channel, thereby isolating the flow channel opening from contact with the alkaline electrolyte in the electrolytic cell.

[0007] Preferably, the main body of the alkaline solution outlet channel is an elongated oval groove, forming a first groove. Several parallel protruding ribs are distributed in the first groove, forming multiple first slots. The alkaline solution outlet gasket is installed in the first groove.

[0008] Preferably, the main body of the alkali inlet channel is a circular groove, forming a second groove. A longitudinal dividing rib is provided in the middle of the second groove. The dividing rib is a long strip protrusion that forms a second slot in the second groove. The alkali inlet gasket is installed in the second groove.

[0009] Preferably, the alkaline outlet gasket includes a main body and several ribs. The main body is elongated with semicircular ends. The diameter of the semicircles at both ends is equal to the width of the elongated main body. The ribs are parallel raised rectangular strips, evenly distributed in the middle area of ​​the main body and perpendicular to the main body.

[0010] Preferably, the width of the main body is 0.1-0.3 mm smaller than the width of the first groove of the alkali outlet channel, the width of the rib is 0.2-0.5 mm smaller than the width of the first slot corresponding to the alkali outlet channel, and the height of the rib is equal to the depth of the protruding rib of the alkali outlet channel.

[0011] Preferably, the main body of the alkali outlet gasket is embedded in the first groove of the alkali outlet channel, and the rib portion is inserted into the first slot of the channel.

[0012] Preferably, the alkali inlet gasket includes a circular main body and a middle partition. The main body is a complete circle, with a vertical raised strip dividing the main body into left and right parts.

[0013] Preferably, the width of the intermediate partition is 0.2-0.5 mm smaller than the width of the second groove corresponding to the alkali inlet channel, and the height is equal to the depth of the partition rib of the alkali inlet channel; the diameter of the circular main body is 0.1-0.3 mm smaller than the diameter of the second groove of the alkali inlet channel.

[0014] Preferably, the circular main body of the alkali inlet gasket is embedded in the second groove of the alkali inlet channel, and the middle partition is inserted into the second slot of the alkali inlet channel.

[0015] Preferably, the gasket is a modified polytetrafluoroethylene gasket, and the multiple electrode plates are stacked and fastened with bolts so that the gasket is tightly clamped between the slot and the electrode plate to achieve a gapless seal.

[0016] The beneficial effect of this utility model is that, compared with the prior art, This invention provides an electrode plate for preventing corrosion at the flow channel opening of an alkaline electrolyzer. By installing a corrosion-resistant gasket that is compatible with the easily corroded flow channel opening on the electrode plate, the possibility of flow channel opening corrosion is greatly reduced while the electrolyzer produces hydrogen through water electrolysis. This prevents corrosion at the flow channel opening of the alkaline electrolyzer, reduces the frequency of electrolyzer maintenance, and improves the electrolysis efficiency and service life of the electrolyzer. Attached Figure Description

[0017] Figure 1 This is a top view of the electrode plates of an alkaline electrolytic cell. The alkaline solution inlet is B, and the alkaline solution outlet is A. Figure 2 This is a side view of the alkaline solution outlet channel of the electrode plate; Figure 3 This is a side view of the alkaline solution inlet channel of the electrode plate. Figure 4 Side view of the gasket at the outlet of the alkali solution; Figure 5 Side view of the gasket at the inlet of the alkali solution flow channel; Figure 6 For gasket assembly (alkali outlet); Figure 7 For gasket assembly drawing (alkali solution inlet); In the diagram: 1. Alkali outlet channel; 101. First tank; 102. Raised rib; 103. First slot; 2. Alkali inlet channel; 201. Second tank body; 202. Separating rib; 203. Second slot; 3. Alkali outlet gasket; 301. Main body; 302. Rib section; 4. Alkali solution inlet gasket; 401. Circular main body; 402. Separator. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. The embodiments described in this application are merely some embodiments of this utility model, not all embodiments. Based on the spirit of this utility model, other embodiments obtained by those skilled in the art without creative effort are all within the protection scope of this utility model.

[0019] In the description of this utility model, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0020] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0021] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0022] In this invention, unless otherwise expressly specified and limited, the first feature "on" or "below" the second feature may be in direct contact with the first and second features, or indirect contact through an intermediate medium. In the description of this specification, references to terms such as "a solution," "some solutions," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that solution or example is included in at least one solution or example of this invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same solution or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more solutions or examples.

[0023] Embodiment 1 of this utility model provides an electrode plate to prevent corrosion at the flow channel opening of an alkaline electrolyzer. By designing a gasket made of modified polytetrafluoroethylene, which is installed at the flow channel openings of the alkaline solution inlet and outlet, the gasket's alkali resistance, high temperature resistance, and corrosion resistance properties, combined with the matching structure of the flow channel opening, effectively protect the flow channel opening and extend the service life of the alkaline electrolyzer.

[0024] Specifically, such as Figure 1 As shown, the electrode plate includes an alkaline solution outlet A, an alkaline solution inlet B, and a gasket. The alkaline solution outlet A is provided with an alkaline solution outlet channel 1, and the alkaline solution inlet B is provided with an alkaline solution inlet channel 2. Gaskets of different shapes and specifications are respectively installed at the alkaline solution outlet channel 1 and the alkaline solution inlet channel 2 to isolate the channel from contact with the alkaline solution.

[0025] like Figure 2-3 As shown, the main body of the alkali outlet channel 1 is an elongated groove, that is, the middle is a long strip-shaped groove and the two ends are semi-circular structures, forming a first groove 101. Several parallel protruding ribs 102 are distributed in the first groove 101, forming multiple first slots 103; the main body of the alkali inlet channel 2 is a circular groove, forming a second groove 201, with a longitudinal dividing rib 202 in the middle. The dividing rib 202 is an elongated protrusion, forming a second slot 203 in the second groove 201. like Figure 4-7 As shown, the gaskets are designed with different shapes and specifications to correspond to the shape of the flow channel opening and are installed accordingly.

[0026] Specifically, the gasket includes an alkaline solution outlet gasket 3 and an alkaline solution inlet gasket 4; The alkaline outlet gasket 3 includes a main body 301 and several rib sections 302. The main body 301 is elongated, with semicircular ends. The diameter of the semicircles at both ends is equal to the width of the elongated middle section, meaning the main body 301 is generally elongated. The rib sections 302 are parallel raised rectangular strips, evenly distributed in the middle area of ​​the main body 301, and perpendicular to the main body.

[0027] The rib portion 302 is a raised structure, the width of which is 0.2-0.5 mm less than the width of the first groove 103 corresponding to the alkaline outlet flow channel 1, and its height is equal to the depth of the raised rib 102 of the alkaline outlet flow channel 1; the edge of the main body portion 301 is a smoothly transitioned semi-circle without sharp edges, and its size matches the size of the first groove 101 of the alkaline outlet flow channel 1. The width of the main body portion 301 is 0.1-0.3 mm smaller than the width of the first groove 101 of the alkaline outlet flow channel 1, so as to achieve tight embedding.

[0028] The main body 301 of the alkali outlet gasket 3 is embedded into the first groove 101 of the alkali outlet channel 1, and the rib part 302 is inserted into the first slot 103 of the channel. It is fixed by the clamping structure of the electrode plate, so that the alkali outlet gasket 3 completely fills the groove of the alkali outlet channel 1 and has no gap with the groove wall.

[0029] The alkaline solution inlet gasket 4 includes a circular main body 401 and a middle partition 402; The main body 401 is a complete circle, and the middle dividing part 402 is a longitudinal protrusion that divides the main body 401 into two parts, namely, the alkaline solution inlet gasket 4 is circular in whole, and the middle is divided into two symmetrical semi-circular areas by the dividing part 402.

[0030] The intermediate partition 402 is a raised structure, the width of which is 0.2-0.5 mm less than the width of the second groove 203 corresponding to the alkali inlet channel 2, and the height is equal to the depth of the partition rib 202 of the alkali inlet channel 2; the edge of the circular main body 401 is a smooth circle, and its diameter is 0.1-0.3 mm smaller than the diameter of the second groove 201 of the alkali inlet channel 2, to ensure tight embedding.

[0031] The circular main body 401 of the alkali inlet gasket 4 is embedded into the second groove 201 of the alkali inlet channel 2, and the middle partition 402 is inserted into the second slot 203 of the alkali inlet channel 2. It is fixed by the clamping structure of the electrode plate, so that the alkali inlet gasket 4 completely fills the second slot 203 of the alkali inlet channel 2, thereby achieving a sealing protection.

[0032] The edges of the first slot 103 and the second slot 203 are rounded to avoid sharp edges from causing wear on the gasket, while also enhancing the fit and sealing with the gasket.

[0033] In a preferred but non-limiting embodiment of this utility model, the gasket material is modified polytetrafluoroethylene, and by changing the size of the gasket, it can be applied to electrolytic cells of different specifications.

[0034] More preferably, the gasket is fixed to the flow channel opening in the following way: 1. Pre-positioning: The main body and rib (separator) of the gasket are respectively embedded in the groove and the slot. The size matching between the slot and the gasket is used to achieve initial positioning and prevent the gasket from being displaced horizontally in the flow channel.

[0035] It is worth noting that the slots are all slightly larger than the gaskets by 0.2-0.5mm. This is to ensure assembly feasibility and avoid installation difficulties or damage to the gaskets. Although modified PTFE gaskets have a certain degree of elasticity, they are still relatively weak materials. If the dimensions of the rib groove at the flow channel and the rib of the gasket are exactly the same (interference fit), it will be difficult for the gasket to be accurately embedded in the rib groove during installation. The rib may be deformed or broken due to forced compression. Furthermore, the processing errors of the flow channel or the gasket (such as dimensional deviations and surface roughness) will further increase the assembly difficulty and may even cause wear on the edge of the gasket.

[0036] Therefore, a gap of 0.2-0.5mm is reserved to accommodate processing errors, ensuring that the gasket can be easily and completely embedded in the flow channel opening, avoiding structural damage during installation.

[0037] 2. Pressing and fixing: Multiple electrode plates of the electrolytic cell are stacked and fastened with bolts, so that the gasket is tightly clamped between the slot and the electrode plate. At this time, the gasket undergoes a slight deformation due to its own elasticity, and completely fits the inner wall of the slot and the contact surface of the electrode plate, achieving a gapless seal.

[0038] The modified polytetrafluoroethylene has slight elasticity and compressibility (compression rate of about 5%-10%). When the electrode plate is tightened by bolts, the gasket will be subjected to vertical pressure. At this time, the rib part will expand slightly to both sides to fill the gap of 0.2-0.5mm and fit tightly with the inner wall of the rib groove. The main body will also deform due to the clamping force and fit completely with the slot (limiting groove) of the flow channel opening to form a gapless seal.

[0039] This "reserved gap + elastic filling" design can eliminate gaps caused by dimensional errors, ensuring that alkaline solution cannot seep into the flow channel body, thus fundamentally avoiding corrosion.

[0040] Furthermore, during the operation of an alkaline electrolytic cell, the temperature of the alkaline solution can reach 80-150℃. The coefficients of thermal expansion of the flow channel (metal) and the gasket (modified polytetrafluoroethylene) differ (approximately 10-20 × 10⁻⁻ for metal). 6 / ℃, polytetrafluoroethylene approximately 100×10⁻ 6 / ℃): Therefore, at high temperatures, the gasket expands much larger than the flow channel opening. The reserved 0.2-0.5mm gap can accommodate the gasket's thermal expansion, preventing deformation, cracking, or damage to the flow channel opening due to excessive compression. At low temperatures, the gasket contracts, but the clamping force of the electrode plate still ensures a proper fit between the gasket and the flow channel opening, and the gap will not increase to the point of affecting the seal due to contraction. This design ensures that the gasket maintains a stable protective effect under different operating conditions.

[0041] In summary, a gap of 0.2-0.5mm is the optimal choice for balancing ease of assembly, sealing reliability, and environmental adaptability. It avoids the installation difficulties of interference fits, achieves gapless sealing through material elasticity and clamping force, and adapts to dimensional fluctuations caused by temperature changes, ensuring corrosion resistance during long-term use.

[0042] 3. Anti-displacement: The interlocking structure of the rib section and the rib groove, the intermediate partition section and the longitudinal partition groove further restricts the rotation or lateral sliding of the gasket, ensuring that the gasket is always in the preset position during long-term use, effectively isolating the alkaline solution from the flow channel body.

[0043] The slot achieves pre-positioning by adapting to the structure of the gasket, and is tightly fixed by the bolt clamping structure of the electrode plate, ultimately preventing corrosion of the flow channel opening.

[0044] Embodiment 2 of this utility model provides a method for preventing corrosion at the flow channel opening of an alkaline electrolytic cell, based on the electrode plate for preventing corrosion at the flow channel opening of an alkaline electrolytic cell described in Embodiment 1, specifically including: The alkaline solution is circulated through a pump, and a water replenishment device is installed to replenish the system with water in a timely manner. The flow sequence of the alkaline solution is as follows: the alkaline solution of a certain concentration is heated by the alkaline solution preheater, and the heated alkaline solution is stored in the alkaline solution buffer tank. The alkaline solution is pumped into the alkaline electrolytic cell as the electrolyte, and an electrolysis test is conducted in the electrolytic cell. After entering the electrolytic cell, the alkaline solution flows into each small chamber, and then into the cathode and anode of each small chamber. It flows in and out through the flow channel with corrosion-resistant gaskets. The hydrogen and oxygen generated by the electrolysis of water are mixed with the alkaline solution. The hydrogen and alkaline solution enter the hydrogen separator, and the oxygen and alkaline solution enter the oxygen separator. The alkaline solution returns to the alkaline solution buffer tank from the hydrogen separator and the oxygen separator.

[0045] The beneficial effect of this utility model is that, compared with the prior art, This invention provides an electrode plate for preventing corrosion at the flow channel opening of an alkaline electrolyzer. By installing a corrosion-resistant gasket that is compatible with the easily corroded flow channel opening on the electrode plate, the possibility of flow channel opening corrosion is greatly reduced while the electrolyzer produces hydrogen through water electrolysis. This prevents corrosion at the flow channel opening of the alkaline electrolyzer, reduces the frequency of electrolyzer maintenance, and improves the electrolysis efficiency and service life of the electrolyzer.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although the utility model has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of this utility model. Any modifications or equivalent substitutions that do not depart from the spirit and scope of this utility model should be covered within the protection scope of the claims of this utility model.

Claims

1. An electrode plate for preventing corrosion at the flow channel inlet of an alkaline electrolytic cell, comprising an alkaline solution outlet and an alkaline solution inlet, characterized in that: The electrode plate further includes a gasket. The alkali outlet is provided with an alkali outlet channel (1), and the alkali inlet is provided with an alkali inlet channel (2). The gasket includes an alkali outlet gasket (3) and an alkali inlet gasket (4). The alkali outlet gasket (3) matching the alkali outlet channel (1) is installed on the alkali outlet channel (1), and the alkali inlet gasket (4) matching the alkali inlet channel (2) is installed on the alkali inlet channel (2) to isolate the channel from contact with the alkaline electrolyte in the electrolytic cell.

2. The electrode plate for preventing corrosion at the flow channel opening of an alkaline electrolytic cell according to claim 1, characterized in that: The main body of the alkaline solution outlet channel (1) is an elongated oval groove, forming a first groove (101). Several parallel protruding ribs (102) are distributed in the first groove (101), and multiple first slots (103) are formed in the first groove (101). The alkaline solution outlet gasket (3) is installed in the first groove (101).

3. The electrode plate for preventing corrosion at the flow channel opening of an alkaline electrolytic cell according to claim 1, characterized in that: The main body of the alkaline inlet channel (2) is a circular groove, forming a second groove (201). A longitudinal dividing rib (202) is provided in the middle of the second groove (201). The dividing rib (202) is a long strip protrusion, forming a second slot (203) in the second groove (201). The alkaline inlet gasket (4) is installed in the second groove (201).

4. The electrode plate for preventing corrosion at the flow channel opening of an alkaline electrolytic cell according to claim 2, characterized in that: The alkaline outlet gasket (3) includes a main body (301) and several ribs (302). The main body (301) is long and has semicircular ends. The diameter of the semicircles at both ends is equal to the width of the long and narrow shape in the middle. The ribs (302) are parallel raised rectangular strips that are evenly distributed in the middle area of ​​the main body (301) and are perpendicular to the main body.

5. The electrode plate for preventing corrosion at the flow channel opening of an alkaline electrolytic cell according to claim 4, characterized in that: The width of the main body (301) is 0.1-0.3 mm smaller than the width of the first groove (101) of the alkaline outlet channel (1), the width of the rib part (302) is 0.2-0.5 mm smaller than the width of the first slot (103) corresponding to the alkaline outlet channel (1), and the height of the rib part (302) is equal to the depth of the protruding rib (102) of the alkaline outlet channel (1).

6. The electrode plate for preventing corrosion at the flow channel opening of an alkaline electrolytic cell according to claim 5, characterized in that: The main body (301) of the alkaline outlet gasket (3) is embedded in the first groove (101) of the alkaline outlet channel (1), and the rib (302) is inserted into the first slot (103) of the channel.

7. The electrode plate for preventing corrosion at the flow channel opening of an alkaline electrolytic cell according to claim 3, characterized in that: The alkaline solution inlet gasket (4) includes a circular main body (401) and an intermediate partition (402). The circular main body (401) is a complete circle, and the middle dividing part (402) is a longitudinal protrusion that divides the circular main body (401) into left and right parts.

8. The electrode plate for preventing corrosion at the flow channel opening of an alkaline electrolytic cell according to claim 7, characterized in that: The width of the intermediate partition (402) is 0.2-0.5 mm smaller than the width of the second slot (203) corresponding to the alkali inlet channel (2), and the height is equal to the depth of the partition rib (202) of the alkali inlet channel (2); the diameter of the circular main body (401) is 0.1-0.3 mm smaller than the diameter of the second groove (201) of the alkali inlet channel (2).

9. The electrode plate for preventing corrosion at the flow channel opening of an alkaline electrolytic cell according to claim 7, characterized in that: The circular main body (401) of the alkali inlet gasket (4) is embedded in the second groove (201) of the alkali inlet channel (2), and the middle partition (402) is inserted into the second slot (203) of the alkali inlet channel (2).

10. The electrode plate for preventing corrosion at the flow channel opening of an alkaline electrolytic cell according to claim 1, characterized in that: The gasket is a modified polytetrafluoroethylene gasket. The multiple electrode plates are stacked and fastened with bolts, so that the gasket is tightly clamped between the slot and the electrode plate to achieve a gapless seal.

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