Alkaline electrolytic cell capable of uniformly distributing alkali liquor

Abstract

The utility model discloses an alkaline electrolytic cell capable of uniformly distributing alkaline liquor, which comprises an end pressing plate, an end polar plate and a plurality of bipolar plates which are sequentially stacked, and the bipolar plates comprise polar plate bodies and polar frames fixedly arranged on the edges of the polar plate bodies. The electrode frame of the bipolar plate and the end electrode plate are respectively provided with an alkali liquor direct flow channel and an alkali liquor backflow channel which are communicated with the electrolysis small chamber, an alkali liquor backflow chamber is formed on the end electrode plate, and the alkali liquor direct flow channel and the alkali liquor backflow channel on the end electrode plate are respectively communicated with the alkali liquor backflow chamber. According to the alkaline electrolytic bath disclosed by the utility model, a structural form of combining direct-current distribution and reflux distribution of alkaline liquor is formed, and the uniformity of flow distribution of the alkaline liquor is greatly improved.

Description

Technical Field

[0001] This utility model relates to the field of alkaline water electrolysis for hydrogen production, and in particular to an alkaline electrolytic cell with uniform distribution of alkaline solution. Background Technology

[0002] The increasing size of alkaline electrolyzers leads to larger diameters of the electrolysis chambers and the accumulation of hundreds of chambers, resulting in excessively large and long tanks. This increases the uneven distribution of electrolyte among the chambers, affecting electrolyte concentration and causing inconsistencies in electrochemical reactions. Consequently, the electrolyzer's lifespan is reduced, and its energy consumption increases. Furthermore, the uneven electrolyte distribution causes temperature differences and prevents the rapid removal of air bubbles, leading to overheating in some chambers. This damages materials such as diaphragms and gaskets, jeopardizing the electrolyzer's operational safety.

[0003] Currently, there are two main technical solutions for hydrogen production devices using a positive and negative alkaline electrolyzer. One is a U-shaped flow method with direct distribution of alkaline solution in the electrolyzer, or a Z-shaped flow method with a groove on the right end electrode plate to form a reflux chamber for reflux distribution. However, both have the problem of large flow deviation. The other method is to shorten the flow path by adding an intermediate electrode plate in the electrolyzer, using intermediate inlet and outlet to achieve uniform distribution of electrolyte and collection and output of generated gas. However, there is the problem of galvanic corrosion of the intermediate electrode plate affecting the durability of the electrolyzer. Utility Model Content

[0004] To address the aforementioned technical problems, this invention proposes a novel alkaline electrolytic cell structure to alter the flow pattern of the alkaline solution and achieve uniform flow distribution of the alkaline solution in each electrolysis chamber.

[0005] The alkaline electrolytic cell of this invention, which provides uniform distribution of alkali solution, includes an end plate, an end electrode plate, and a plurality of bipolar plates stacked sequentially. Each bipolar plate includes an electrode body and an electrode frame fixed to the edge of the body. The electrode frame and the end electrode plate are respectively provided with an alkali solution direct flow channel and an alkali solution reflux channel communicating with an electrolysis chamber. An alkali solution reflux chamber is formed on the end electrode plate. The alkali solution direct flow channel and the alkali solution reflux channel on the end electrode plate are respectively connected to the alkali solution reflux chamber.

[0006] In one embodiment, the direct flow channel of the alkali solution and the return flow channel of the alkali solution are respectively disposed at the bottom of the bipolar plate and the terminal plate.

[0007] In one embodiment, a first through groove and a second through groove are respectively provided on the bipolar plate along the radial direction of the electrode frame. The direct flow channel of the alkali solution is connected to the electrolysis chamber through the first through groove, and the return flow channel of the alkali solution is connected to the electrolysis chamber through the second through groove.

[0008] In one embodiment, the bottom of the first end plate is provided with an alkali inlet, and the alkali is distributed from the alkali inlet to the electrolysis chamber and the alkali reflux chamber through the alkali direct flow channel; the alkali in the alkali reflux chamber is redistributed to the electrolysis chamber through the alkali reflux flow channel.

[0009] In one embodiment, the upper part of the bipolar plate frame is provided with a hydrogen channel and an oxygen channel, respectively. The upper part of the first end plate is provided with a hydrogen outlet aligned with the hydrogen channel and an oxygen outlet aligned with the oxygen channel. The hydrogen outlet and the hydrogen channel are connected to form the hydrogen output channel of the alkaline electrolytic cell. The hydrogen output channel is connected to the cathode side of the electrolysis chamber. The oxygen outlet and the oxygen channel are connected to form the oxygen output channel of the alkaline electrolytic cell. The oxygen output channel is connected to the anode side of the electrolysis chamber.

[0010] In one embodiment, a third through groove and a fourth channel are further provided on the upper part of the electrode frame along the radial direction of the electrode frame. The third through groove is disposed on the cathode side of the bipolar plate and communicates with the hydrogen channel, and the fourth channel is disposed on the anode side of the bipolar plate and communicates with the oxygen channel.

[0011] In one embodiment, a fifth channel and a sixth channel are provided on the lower part of the end plate along the radial direction of the end plate. The alkali direct flow channel at the lower part of the end plate is connected to the alkali return chamber through the fifth channel, and the alkali return flow channel is connected to the alkali return chamber through the sixth channel.

[0012] In one embodiment, each of the bipolar plates is provided with two direct alkali channels and one reflux alkali channel, with the direct alkali channels symmetrically distributed on both sides of the reflux alkali channel.

[0013] In one embodiment, the terminal plate is provided with two direct alkali channels and one reflux alkali channel, and the direct alkali channels and reflux alkali channels on the terminal plate are corresponding to the direct alkali channels and reflux alkali channels on the bipolar plate.

[0014] In one embodiment, the alkali direct flow channels of all components are arranged in the same straight line along the axial direction, and the alkali return flow channels of all components are arranged in the same straight line along the axial direction.

[0015] Compared with the prior art, the alkaline electrolytic cell of this invention forms a structure that combines direct current distribution and reflux distribution of alkali solution, which greatly improves the uniformity of alkali solution flow distribution.

[0016] The above-mentioned technical features can be combined in various technically feasible ways to generate new implementation schemes, as long as the purpose of this utility model can be achieved. Attached Figure Description

[0017] The present invention will now be described in more detail based on embodiments that are not limiting only, and with reference to the accompanying drawings. Wherein:

[0018] Figure 1 An exploded view of an alkaline electrolytic cell with uniform alkali distribution according to the present invention is shown.

[0019] In the figures, identical components are labeled with the same reference numerals. The figures are not drawn to scale.

[0020] The attached figures are labeled as follows:

[0021] 1. Alkali inlet; 2. Alkali direct flow channel; 3. Alkali reflux channel; 4. Electrolysis chamber; 5. First through-slot; 6. Second through-slot; 7. Fifth through-slot; 8. Sixth through-slot; 9. Alkali reflux chamber; 10. Right end pressure plate; 11. Right end electrode plate; 12. Third through-slot; 13. Oxygen channel; 14. Hydrogen channel; 15. Bipolar plate; 16. Oxygen outlet; 17. Hydrogen outlet; 18. Left end pressure plate. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, as long as there is no conflict, the various embodiments and features of the present invention can be combined with each other, and the resulting technical solutions are all within the protection scope of the present invention.

[0023] The parts not mentioned in this utility model can be achieved by adopting or referencing existing technologies.

[0024] like Figure 1 As shown, the alkaline electrolytic cell of this invention with uniform alkali distribution includes end pressure plates, end electrode plates, and multiple bipolar plates 15 stacked sequentially. Each bipolar plate 15 includes an electrode body and an electrode frame fixed to the edge of the body. The electrode frame and end electrode plate of the bipolar plate 15... Figure 1 The right end plate 11 shown in the figure is provided with an alkali direct flow channel 2 and an alkali return flow channel 3 that are connected to the electrolysis chamber 4. An alkali return chamber 9 is formed on the end plate. The alkali direct flow channel 2 and the alkali return flow channel 3 on the end plate (right end plate 11) are connected to the alkali return chamber 9 respectively.

[0025] In specific embodiments of this application, such as Figure 1 As shown, the electrolytic cell includes, from left to right, a left end pressure plate 18, multiple bipolar plates 15, a right end electrode plate 11, and a right end pressure plate 10 stacked together.

[0026] Through the above technical solution, the alkaline solution in the alkaline electrolyzer is distributed to the electrolysis chamber 4 via the alkaline solution direct flow channel 2 and then directly to the right end electrode plate 11, reaching the alkaline solution return chamber 9. The alkaline solution in the alkaline solution return chamber 9 is then redistributed to the electrolysis chamber 4 via the alkaline solution return flow channel 3. Combining the traditional U-shaped and Z-shaped flow structures, the defects of different alkaline solution flow paths and different pressure drop differences between the front and rear ends are made up for.

[0027] In other alternative embodiments, the alkaline electrolyzer may also include a left-end electrode plate.

[0028] In other alternative embodiments, the number of alkali direct flow channels 2, alkali reflux channels 3, and electrolysis chambers can be increased by adding more bipolar plates.

[0029] In an optional embodiment, the alkali direct flow channels 2 of all components are arranged in the same straight line along the axial direction, and the alkali return flow channels 3 of all components are arranged in the same straight line along the axial direction.

[0030] By arranging the alkali direct flow channels 2 of all components along the same straight line and the alkali return flow channels 3 of all components along the same straight line, it is not only convenient for production and processing, but also ensures that the alkali in each alkali distribution channel has the same potential energy, which is more conducive to the uniform distribution of alkali in each electrolysis chamber 4.

[0031] In a specific embodiment of this utility model, the alkali direct flow channel 2 and the alkali return flow channel 3 can be arranged on the electrode frame in any suitable manner. Optionally, such as... Figure 1 As shown, in order to facilitate the distribution of alkali solution from the bottom into the electrolysis chamber 4, the alkali solution direct flow channel 2 and the alkali solution return flow channel 3 are respectively set at the bottom of the bipolar plate frame.

[0032] In an optional embodiment, such as Figure 1 As shown, a first through groove 5 and a second through groove 6 are respectively provided on the bipolar plate 15 along the radial direction of the electrode frame. The first through groove 5 is the DC inlet of the electrolysis chamber, and the alkali solution DC flow channel 2 is connected to the electrolysis chamber 4 through the first through groove 5; the second through groove 6 is the reflux inlet of the electrolysis chamber, and the alkali solution reflux flow channel 3 is connected to the electrolysis chamber 4 through the second through groove 6.

[0033] In an optional embodiment, the first end plate ( Figure 1 The bottom of the left end pressure plate 18 shown is provided with an alkali inlet 1. The alkali solution flows from the alkali inlet 1 through the alkali direct flow channel 2 to the right end electrode plate 11. The alkali solution is distributed to the electrolysis chamber 4 and the alkali return chamber 9. The alkali solution in the alkali return chamber 9 is then distributed to the electrolysis chamber 4 through the alkali return flow channel 3.

[0034] In an optional embodiment, the upper part of the bipolar plate 15's frame is provided with a hydrogen channel 14 and an oxygen channel 13, respectively. The upper part of the left end pressure plate 18 is provided with a hydrogen outlet 17 and an oxygen outlet 16, respectively. The hydrogen outlet 17 is connected to the hydrogen channel 14 to form the hydrogen output channel of the electrolyzer, and the oxygen outlet 16 is connected to the oxygen channel 13 to form the oxygen output channel of the electrolyzer. The hydrogen output channel is connected to the cathode side of the electrolysis chamber 4, and the oxygen output channel is connected to the anode side of the electrolysis chamber 4.

[0035] Each electrolysis chamber 4 has two plates on both sides, and a diaphragm (not shown in the figure) is placed in the middle of the plates. The diaphragm does not allow gas to pass through (it has low resistance to ions and appropriate permeability to the electrolyte) to prevent the hydrogen and oxygen generated on both sides of the electrolysis chamber 4 from mixing.

[0036] The hydrogen 14 and oxygen 13 generated by electrolysis in the electrolysis chamber 4 are discharged through the hydrogen channel 14 and oxygen channel 13 respectively, and then through the hydrogen outlet 17 and oxygen outlet 16 respectively.

[0037] In an optional embodiment, a third channel 12 and a fourth channel (not shown in the figure) are further provided on the upper part of the electrode frame of the bipolar plate 15 along the radial direction of the electrode frame. The third channel 12 is provided on the cathode side of the bipolar plate 15 as an outlet of the electrolysis chamber and communicates with the hydrogen channel 14. The fourth channel is provided on the anode side of the bipolar plate 15 as an outlet of the electrolysis chamber and communicates with the oxygen channel 13.

[0038] In an optional embodiment, a fifth through groove 7 and a sixth through groove 8 are further provided on the right end electrode plate 11 along the radial direction of the right end electrode plate 11. The alkali direct flow channel 2 at the lower part of the right end electrode plate 11 is connected to the alkali return chamber 9 through the fifth through groove 7, and the alkali return flow channel 3 is connected to the alkali return chamber 9 through the sixth through groove 8.

[0039] In an optional embodiment, each bipolar plate 15 is provided with two direct alkali channels 2 and one reflux alkali channel 3, with the direct alkali channels 2 symmetrically distributed on both sides of the reflux alkali channel 3.

[0040] In an optional embodiment, the right end electrode plate 11 is provided with two direct alkali flow channels 2 and one alkali return flow channel 3, and the direct alkali flow channels 2 and one alkali return flow channel 3 on the right end electrode plate 11 are correspondingly provided with the direct alkali flow channels 2 and alkali return flow channels 3 on the bipolar plate 15.

[0041] In other alternative embodiments, the alkali reflux chamber 9 is formed by a groove in the right end electrode plate 11.

[0042] The electrolysis process of the alkaline electrolyzer of this application is illustrated below with a specific embodiment:

[0043] The alkali solution is pumped through an opening (alkali inlet 1) at the bottom of the left end pressure plate 18 into the electrolytic cell. The alkali solution flows through openings on both sides (alkali direct flow channels 2) at the bottom of the bipolar plate 15, penetrating to the right end plate 11. During this process, the alkali solution is simultaneously distributed to the electrolysis chamber 4 via a second channel 6 connected to the alkali direct flow channel 2. Inside the electrolysis chamber 4, the alkali solution undergoes an electrochemical reaction, producing hydrogen and oxygen. These gases are carried out of the electrolysis chamber 4 by the alkali solution through the outlets (third channel 12 and fourth channel), and converge through hydrogen channel 14 and oxygen channel 13, exiting from hydrogen outlet 17 and oxygen outlet 16 respectively, forming a gas-liquid circuit. Simultaneously, the alkali solution penetrating to the bottom enters the alkali return chamber 9 through the inlet (fifth channel 7) of the right end plate 11. The alkali return chamber 9 has sufficient volume. After the alkali solution fills the alkali solution reflux chamber 9, under the driving condition of the alkali solution circulation pump, the alkali solution flows through the reflux outlet (sixth channel 8) of the reflux chamber and through the alkali solution reflux channel 3, forming a reflux flow from the right end electrode plate 11 to the left end pressure plate 18. At the same time, it flows through the reflux inlet (first channel 5) of the electrolysis chamber, completing the redistribution of the electrolysis chamber 4.

[0044] Because electrolysis raises the temperature of the electrolyte, it is circulated to maintain the electrolyte temperature between 85 and 90 degrees Celsius (the optimal electrolysis temperature). The electrolyte is pumped into the electrolytic cell by an alkaline circulation pump, and the output is a gas-liquid mixture. The gas is separated by a gas-liquid separator, and the remaining electrolyte is cooled and then pumped back into the electrolytic cell by the circulation pump.

[0045] The alkaline electrolytic cell with uniform alkali distribution in this application forms a structure that combines direct flow distribution and reflux distribution of alkali. By combining the two flow forms, it makes up for the defects of different alkali flow paths and different pressure drop differences between the front and rear ends. According to fluid simulation calculations, the uniformity of alkali flow distribution is significantly improved, the temperature consistency is higher, and the energy consumption performance is better.

[0046] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar words used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Words such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Words such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. In the description of this invention, the terms "upper," "lower," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this invention 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. When the absolute position of the described object changes, the relative positional relationship may also change accordingly, and therefore should not be construed as a limitation of this invention.

[0047] Therefore, those skilled in the art should recognize that although the present invention has been described with reference to preferred embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the present invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner as long as there is no structural conflict. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An alkaline electrolytic cell with uniform alkali solution distribution, characterized in that, The device includes a stacked end plate, an end electrode plate, and multiple bipolar plates. Each bipolar plate includes an electrode plate body and an electrode frame fixed to the edge of the electrode plate body. The electrode frame and the end electrode plate are respectively provided with an alkali direct flow channel and an alkali reflux channel communicating with an electrolysis chamber. An alkali reflux chamber is formed on the end electrode plate. The alkali direct flow channel and the alkali reflux channel on the end electrode plate are respectively connected to the alkali reflux chamber. The direct flow channel of the alkali solution and the return flow channel of the alkali solution are respectively disposed at the bottom of the bipolar plate and the end plate; The direct flow channels of the alkali solution in all components are arranged in a straight line along the axial direction, and the return flow channels of the alkali solution in all components are arranged in a straight line along the axial direction.

2. The alkaline electrolytic cell with uniform alkali distribution according to claim 1, characterized in that, A first through groove and a second through groove are respectively provided on the bipolar plate along the radial direction of the electrode frame. The direct flow channel of the alkali solution is connected to the electrolysis chamber through the first through groove, and the return flow channel of the alkali solution is connected to the electrolysis chamber through the second through groove.

3. The alkaline electrolytic cell with uniform alkali distribution according to claim 2, characterized in that, The bottom of the first end plate is provided with an alkali inlet. The alkali solution is distributed from the alkali inlet to the electrolysis chamber and the alkali reflux chamber through the alkali direct flow channel. The alkali solution in the alkali reflux chamber is then redistributed to the electrolysis chamber through the alkali reflux flow channel.

4. The alkaline electrolytic cell with uniform alkali distribution according to claim 3, characterized in that, The upper part of the bipolar plate frame is provided with a hydrogen channel and an oxygen channel, respectively. The upper part of the first end plate is provided with a hydrogen outlet aligned with the hydrogen channel and an oxygen outlet aligned with the oxygen channel. The hydrogen outlet and the hydrogen channel are connected to form the hydrogen output channel of the alkaline electrolytic cell. The hydrogen output channel is connected to the cathode side of the electrolysis chamber. The oxygen outlet and the oxygen channel are connected to form the oxygen output channel of the alkaline electrolytic cell. The oxygen output channel is connected to the anode side of the electrolysis chamber.

5. The alkaline electrolytic cell with uniform alkali distribution according to claim 4, characterized in that, A third through groove and a fourth channel are provided on the upper part of the electrode frame along the radial direction of the electrode frame. The third through groove is located on the cathode side of the bipolar plate and communicates with the hydrogen channel. The fourth channel is located on the anode side of the bipolar plate and communicates with the oxygen channel.

6. The alkaline electrolytic cell with uniform alkali distribution according to claim 2, characterized in that, The lower part of the end plate is provided with a fifth channel and a sixth channel along the radial direction of the end plate. The alkali direct flow channel at the lower part of the end plate is connected to the alkali return chamber through the fifth channel, and the alkali return flow channel is connected to the alkali return chamber through the sixth channel.

7. The alkaline electrolytic cell with uniform alkali distribution according to claim 1, characterized in that, Each of the bipolar plates is provided with two direct alkali flow channels and one alkali return flow channel, with the direct alkali flow channels symmetrically distributed on both sides of the alkali return flow channel.

8. The alkaline electrolytic cell with uniformly distributed alkali solution according to claim 7, characterized in that, The terminal plate is provided with two direct alkali flow channels and one alkali return flow channel, which are corresponding to the direct alkali flow channels and alkali return flow channels on the bipolar plate.

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