Hydrogen production apparatus and method for reducing hydrogen content in oxygen by alkaline electrolysis

Abstract

This invention discloses an alkaline electrolysis hydrogen production device and method for reducing the hydrogen content in oxygen, comprising an alkaline electrolyzer, a hydrogen-side gas-liquid separator, a hydrogen-side alkaline solution circulation pump, an oxygen-side gas-liquid separator, and an oxygen-side alkaline solution circulation pump. A third electrode is provided on the anode side of the alkaline electrolyzer, and a load is externally connected between the third electrode and the anode of the alkaline electrolyzer. The third electrode, the anode of the alkaline electrolyzer, the load, and the alkaline electrolyte form a fuel cell circuit on the anode side of the alkaline electrolyzer. This invention, by inserting a third electrode into the anode chamber of the alkaline electrolyzer to form a hydrogen-oxygen fuel cell circuit with the anode of the alkaline electrolyzer, allows the permeated hydrogen in the anode chamber of the alkaline electrolyzer to undergo an electrochemical reverse reaction and be removed, thereby reducing the hydrogen concentration in oxygen in the alkaline water electrolysis hydrogen production system and improving the system's safety.

Description

Technical Field

[0001] This invention relates to the field of water electrolysis for hydrogen production technology, specifically to an alkaline water electrolysis hydrogen production apparatus and method for reducing the hydrogen content in oxygen. Background Technology

[0002] Water electrolysis for hydrogen production is currently the fastest-growing method for producing green hydrogen, widely used in chemical, metallurgical, and transportation industries to achieve deep decarbonization. The goal of large-scale water electrolysis hydrogen production is to achieve a balance between "large scale," "low energy consumption," and "high stability." However, the safety issue posed by excessively high hydrogen concentrations in oxygen is a bottleneck limiting its large-scale application. When the hydrogen concentration exceeds 4%, an explosion is highly likely. Therefore, to solve this problem, various methods for reducing hydrogen concentration in oxygen need to be developed to ensure the safe operation of the water electrolysis system.

[0003] Meanwhile, hydrogen and oxygen can form a highly oxidizing environment under certain conditions, accelerating equipment corrosion and shortening its lifespan. In some cases, oxygen is a commercially valuable byproduct; however, the hydrogen entrained in it reduces its purity, affecting the quality and efficiency of downstream processes. This is particularly true in industrial processes requiring high-purity oxygen (such as semiconductor manufacturing and medical applications), where low-purity oxygen can lead to product quality problems. Furthermore, the reduced oxygen purity may necessitate additional purification steps and equipment, increasing production costs. Frequent equipment maintenance and replacement also contribute to increased operating costs.

[0004] Reducing the hydrogen content on the anode side of an alkaline electrolyzer can fundamentally lower the hydrogen content in the oxygen produced by alkaline water electrolysis. Therefore, reducing the hydrogen content on the anode side of an alkaline electrolyzer is key to improving the safety of alkaline water electrolysis hydrogen production systems. Summary of the Invention

[0005] The purpose of this invention is to provide an alkaline electrolysis hydrogen production device and method for reducing the hydrogen content in oxygen, thereby solving the problem of increased hydrogen content in oxygen caused by hydrogen permeation during alkaline water electrolysis hydrogen production. This invention establishes a fuel cell by inserting a third electrode on the anode side of the alkaline electrolyzer and connecting an external load between the third electrode and the anode. This causes the hydrogen permeating from the cathode side of the alkaline electrolyzer into the anode side to undergo an electrochemical reverse reaction, reducing the hydrogen content in the oxygen at the anode side of the alkaline electrolyzer. This, in turn, reduces the hydrogen content in the oxygen of the alkaline water electrolysis hydrogen production system and improves the safety of the system.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] The first aspect of the present invention is to provide an alkaline electrolysis hydrogen production apparatus for reducing the hydrogen content in oxygen, comprising an alkaline electrolyzer, a hydrogen-side gas-liquid separator, a hydrogen-side alkaline solution circulation pump, an oxygen-side gas-liquid separator, and an oxygen-side alkaline solution circulation pump.

[0008] The alkaline electrolyzer has a third electrode on the anode side, and a load is connected between the third electrode and the anode of the alkaline electrolyzer. The third electrode, the anode of the alkaline electrolyzer, the load, and the alkaline electrolyte form a fuel cell circuit on the anode side of the alkaline electrolyzer.

[0009] Furthermore, the alkaline electrolytic cell includes a cathode plate and an anode plate, the cathode plate and the anode plate are spaced apart and a diaphragm is provided between them, an anode electrode is provided between the diaphragm and the anode plate, and a third electrode is provided between the anode electrode and the diaphragm; a cathode electrode is provided between the diaphragm and the cathode plate.

[0010] Furthermore, the third electrode, the anode electrode, and the cathode electrode are made of the same electrode material.

[0011] Furthermore, the third electrode is coated with a catalyst to promote the oxidation of hydrogen.

[0012] Furthermore, the catalyst is a platinum-based catalyst or titanium dioxide.

[0013] Furthermore, the third electrode is positioned 1-2 cm from the diaphragm.

[0014] The third electrode is placed 1-2 cm from the diaphragm, so that the hydrogen gas on the cathode side can pass through the diaphragm into the anode side and effectively contact the catalyst on the third electrode to undergo an electrochemical reverse reaction, thereby achieving effective removal of hydrogen permeation on the anode side of the alkaline electrolyzer.

[0015] Furthermore, the third electrode is a porous electrode with a porosity of 40% to 70%.

[0016] The third electrode is a porous electrode with a porosity of 40% to 70%, which ensures sufficient contact between the alkaline electrolyte and the catalyst, and allows the alkaline electrolyte to pass through smoothly without being significantly obstructed by the porous structure.

[0017] Furthermore, the third electrode is detachably inserted into the alkaline electrolytic cell.

[0018] The third electrode is detachably inserted into the alkaline electrolytic cell, facilitating its maintenance and replacement.

[0019] Furthermore, the alkaline electrolyzer has an oxygen-side gas-liquid mixed phase outlet at the top of the anode side and a hydrogen-side gas-liquid mixed phase outlet at the top of the cathode side; the alkaline electrolyzer has a mixed alkaline solution inlet at the bottom and a mixed alkaline solution inlet line at the mixed alkaline solution inlet.

[0020] The hydrogen-side gas-liquid separator has a first gas-liquid mixed phase inlet in the middle, a first liquid phase outlet at the bottom, and a first gas phase outlet at the top.

[0021] The oxygen-side gas-liquid separator is provided with a second gas-liquid mixed phase inlet in the middle, a second gas phase outlet at the top, and a second liquid phase outlet at the bottom.

[0022] The hydrogen-side gas-liquid mixed phase outlet is connected to the first gas-liquid mixed phase inlet via a pipeline, the first liquid phase outlet is connected to the mixed alkali inlet line via a pipeline, and a first gas phase outlet line is provided at the first gas phase outlet.

[0023] The oxygen-side gas-liquid mixed phase outlet is connected to the second gas-liquid mixed phase inlet via a pipeline, the second liquid phase outlet is connected to the mixed alkali inlet line via a pipeline, and a second gas phase outlet line is provided at the second gas phase outlet.

[0024] A second aspect of the present invention provides an alkaline electrolytic hydrogen production method for reducing the hydrogen content in oxygen, employing the aforementioned alkaline electrolytic hydrogen production apparatus for reducing the hydrogen content in oxygen, comprising the following steps:

[0025] S1. Under the action of direct current, the alkaline electrolyte in the alkaline electrolyzer becomes a gas-liquid mixture containing a large number of microbubbles; wherein, the anode, third electrode, load and alkaline electrolyte of the alkaline electrolyzer form a fuel cell circuit on the anode side of the alkaline electrolyzer, so that the permeated hydrogen entering the anode side of the alkaline electrolyzer undergoes an electrochemical reverse reaction, thereby achieving deep removal of hydrogen from oxygen on the anode side of the alkaline electrolyzer;

[0026] S2. The gas-liquid mixture on the cathode side of the alkaline electrolyzer is pumped into the hydrogen-side gas-liquid separator for gas-liquid separation by the hydrogen-side alkaline solution circulation pump, and the gas-liquid mixture on the anode side of the alkaline electrolyzer is pumped into the oxygen-side gas-liquid separator for gas-liquid separation by the oxygen-side alkaline solution circulation pump.

[0027] S3. After gravity settling, the gaseous products separated by the hydrogen-side gas-liquid separator and the oxygen-side gas-liquid separator are discharged from the top of the gas-liquid separator and enter the next processing step.

[0028] S4. After gas-liquid separation, the hydrogen-side circulating alkaline solution and the oxygen-side circulating alkaline solution are re-entered into the alkaline electrolytic cell for electrolysis under the action of the hydrogen-side alkaline solution circulation pump and the oxygen-side alkaline solution circulation pump, respectively.

[0029] Compared with the prior art, the present invention has at least the following technical effects:

[0030] 1. This invention provides a fuel cell circuit by setting a third electrode on the anode side of an alkaline electrolyzer and connecting an external load between the third electrode and the anode. The anode, third electrode, load, and alkaline electrolyte of the alkaline electrolyzer constitute a fuel cell circuit on the anode side of the alkaline electrolyzer. Through this fuel cell circuit, the permeated hydrogen on the anode side of the alkaline electrolyzer undergoes an electrochemical reverse reaction, completing the deep removal of hydrogen from the oxygen on the anode side of the alkaline electrolyzer, thereby reducing the hydrogen content in the oxygen of the electrolytic hydrogen production system and improving the safety of the electrolytic hydrogen production system.

[0031] 2. This invention constructs a fuel cell circuit by installing a third electrode in an alkaline electrolyzer, causing an electrochemical reverse reaction in the permeated hydrogen on the anode side of the electrolyzer. This significantly reduces the hydrogen content in the oxygen at the anode side of the alkaline electrolyzer, ensuring the safe and stable operation of the alkaline water electrolysis hydrogen production system under fluctuating operating conditions. Compared to existing technologies that reduce the hydrogen content in the oxygen by adjusting the operating parameters of the alkaline electrolyzer, this invention fundamentally reduces the hydrogen content in the oxygen in the alkaline water electrolysis hydrogen production system, avoiding unpredictable losses that may result from monitoring errors. Furthermore, the third electrode of this invention has a simple structure and is easy to install. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the alkaline electrolysis hydrogen production device for reducing the hydrogen content in oxygen according to the present invention.

[0033] Figure 2 This is a schematic diagram of the alkaline electrolytic cell of the present invention.

[0034] 10-Alkaline electrolytic cell; 11-Cathode plate; 12-Cathode electrode; 13-Hydrogen-side gas-liquid mixed phase outlet; 14-Diaphragm; 15-Third electrode; 16-Anode electrode; 17-Anode plate; 18-Oxygen-side gas-liquid mixed phase outlet; 19-Mixed alkaline solution inlet; 191-Mixed alkaline solution inlet line;

[0035] 20 - Hydrogen-side gas-liquid separator; 21 - First gas-liquid mixed phase inlet; 22 - First liquid phase outlet; 23 - First gas phase outlet; 231 - First gas phase outlet line;

[0036] 30 - Oxygen-side gas-liquid separator; 31 - Second gas-liquid mixed phase inlet; 32 - Second liquid phase outlet; 33 - Second gas phase outlet; 331 - Second gas phase outlet line;

[0037] 40-DC power supply;

[0038] 50-load;

[0039] 61 - Hydrogen-side alkaline solution circulation pump; 62 - Oxygen-side alkaline solution circulation pump. Detailed Implementation

[0040] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. It should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of the present invention. Experimental methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions or according to the conditions recommended by the manufacturer.

[0041] See Figures 1-2 The alkaline electrolysis hydrogen production device for reducing the hydrogen content in oxygen according to the present invention includes an alkaline electrolyzer 10, a hydrogen-side gas-liquid separator 20, an oxygen-side gas-liquid separator 30, a hydrogen-side alkaline solution circulation pump 61, and an oxygen-side alkaline solution circulation pump 62.

[0042] See also Figure 2 The alkaline electrolytic cell 10 includes a cathode plate 11 and an anode plate 17, which are spaced apart and separated by a diaphragm 14. A cathode electrode 12 is disposed between the cathode plate 11 and the diaphragm 14, and an anode electrode 16 is disposed between the anode plate 17 and the diaphragm 14. The cathode plate 11, the cathode electrode 12, and the diaphragm 14 constitute the cathode chamber of the alkaline electrolytic cell 10. The anode plate 17, the anode electrode 16, and the diaphragm 14 constitute the anode chamber of the alkaline electrolytic cell 10.

[0043] A third electrode 15 is provided in the anode chamber of the alkaline electrolyzer 10. The third electrode 15 is positioned between the anode electrode 16 and the diaphragm 14, and a load 50 is externally connected between the third electrode 15 and the anode electrode 16. This allows the third electrode 15, the anode electrode 16, the load 50, and the alkaline electrolyte to form a fuel cell circuit on the anode side of the alkaline electrolyzer 10. Through this fuel circuit, the permeated hydrogen on the anode side of the alkaline electrolyzer 10 undergoes an electrochemical reverse reaction, completing the deep removal of hydrogen from the oxygen on the anode side of the alkaline electrolyzer. This reduces the hydrogen content in the oxygen in the alkaline water electrolysis hydrogen production system and improves the safety of the electrolysis hydrogen production system.

[0044] See also Figure 1In use, the alkaline electrolytic cell 10 is first connected to the DC power supply 40. The positive terminal of the DC power supply 40 is connected to the anode electrode 16, and the negative terminal is connected to the cathode electrode 12. Under the action of DC power, the alkaline electrolyte in the alkaline electrolytic cell 10 becomes a gas-liquid mixture containing a large number of microbubbles (because the diaphragm 14 cannot completely prevent hydrogen molecules from permeating from the cathode chamber to the anode chamber of the alkaline electrolytic cell, the hydrogen content in the oxygen on the anode side of the alkaline electrolytic cell increases). The permeated hydrogen on the anode side of the alkaline electrolytic cell undergoes an electrochemical reverse reaction through the fuel cell circuit set on this side (composed of the anode of the alkaline electrolytic cell, the third electrode 15, the load 50, and the alkaline electrolyte), thereby achieving deep removal of hydrogen from the oxygen on the anode side of the alkaline electrolytic cell. The gas-liquid mixture in the cathode chamber of the alkaline electrolyzer 10 is pumped into the hydrogen-side gas-liquid separator 20 by the hydrogen-side alkaline solution circulation pump 61 for gas-liquid separation. The separated hydrogen gas is discharged from the top of the hydrogen-side gas-liquid separator 20 and enters the next processing step (such as drying and pressurizing collection). The gas-liquid mixture in the anode chamber of the alkaline electrolyzer 10 is pumped into the oxygen-side gas-liquid separator 30 by the oxygen-side alkaline solution circulation pump 62 for gas-liquid separation. The separated oxygen gas is discharged from the top of the oxygen-side gas-liquid separator 30 and enters the next processing step (such as drying and pressurizing collection). After gas-liquid separation, the hydrogen-side circulating alkaline solution and the oxygen-side circulating alkaline solution re-enter the alkaline electrolyzer 10 for electrolysis under the action of the hydrogen-side alkaline solution circulation pump 61 and the oxygen-side alkaline solution circulation pump 62, respectively.

[0045] Furthermore, the third electrode 15, the anode electrode 16, and the cathode electrode 12 are made of the same electrode material.

[0046] Furthermore, the third electrode 15 is coated with a catalyst to promote the oxidation of hydrogen.

[0047] Furthermore, the catalyst is a platinum-based catalyst or titanium dioxide.

[0048] Furthermore, the third electrode 15 is disposed at a distance of 1-2 cm from the diaphragm 14.

[0049] The third electrode 15 is placed 1-2 cm away from the diaphragm 14, so that the hydrogen gas on the cathode side can pass through the diaphragm and enter the anode side, and can effectively contact the catalyst on the third electrode 15 to carry out an electrochemical reverse reaction, thereby achieving effective removal of hydrogen permeation on the anode side of the alkaline electrolyzer 10.

[0050] Furthermore, the third electrode 15 is a porous electrode with a porosity of 40% to 70%.

[0051] The third electrode 15 is a porous electrode with a porosity of 40% to 70%, which can ensure sufficient contact between the alkaline electrolyte and the catalyst, and allow the alkaline electrolyte to pass through smoothly without being significantly hindered by the porous structure.

[0052] Furthermore, the third electrode 15 is detachably inserted into the alkaline electrolytic cell 10.

[0053] The third electrode 15 is detachably inserted into the alkaline electrolytic cell 10, which facilitates the maintenance and replacement of the third electrode 15.

[0054] Furthermore, the alkaline electrolytic cell 10 has an oxygen-side gas-liquid mixed phase outlet 18 at the top of the anode side and a hydrogen-side gas-liquid mixed phase outlet 13 at the top of the cathode side; the alkaline electrolytic cell 10 has a mixed alkaline solution inlet 19 at the bottom and a mixed alkaline solution inlet line 191 at the mixed alkaline solution inlet 19.

[0055] The hydrogen-side gas-liquid separator 20 has a first gas-liquid mixed phase inlet 21 in the middle, a first liquid phase outlet 22 at the bottom, and a first gas phase outlet 23 at the top.

[0056] The oxygen-side gas-liquid separator 30 has a second gas-liquid mixed phase inlet 31 in the middle, a second gas phase outlet 33 at the top, and a second liquid phase outlet 32 ​​at the bottom.

[0057] The hydrogen-side gas-liquid mixed phase outlet 13 is connected to the first gas-liquid mixed phase inlet 21 via a pipeline, the first liquid phase outlet 22 is connected to the mixed alkali inlet line 191 via a pipeline, and the first gas phase outlet 23 is provided with a first gas phase outlet line 231.

[0058] The oxygen-side gas-liquid mixed phase outlet 18 is connected to the second gas-liquid mixed phase inlet 31 via a pipeline, the second liquid phase outlet 32 ​​is connected to the mixed alkali inlet line 191 via a pipeline, and the second gas phase outlet 33 is provided with a second gas phase outlet line 331.

[0059] A second aspect of the present invention provides an alkaline electrolytic hydrogen production method for reducing the hydrogen content in oxygen, employing the aforementioned alkaline electrolytic hydrogen production apparatus for reducing the hydrogen content in oxygen, comprising the following steps:

[0060] S1. Under the action of direct current, the alkaline electrolyte in the alkaline electrolyzer 10 becomes a gas-liquid mixture containing a large number of microbubbles; wherein, the anode, the third electrode 15, the load 50 and the alkaline electrolyte of the alkaline electrolyzer 10 form a fuel cell circuit on the anode side of the alkaline electrolyzer 10, so that the permeated hydrogen entering the anode side of the alkaline electrolyzer 10 undergoes an electrochemical reverse reaction, thereby achieving deep removal of hydrogen from oxygen on the anode side of the alkaline electrolyzer 10;

[0061] S2. The gas-liquid mixture on the cathode side of the alkaline electrolytic cell 10 is pumped into the hydrogen-side gas-liquid separator 20 for gas-liquid separation by the hydrogen-side alkaline circulation pump 61, and the gas-liquid mixture on the anode side of the alkaline electrolytic cell 10 is pumped into the oxygen-side gas-liquid separator 30 for gas-liquid separation by the oxygen-side alkaline circulation pump 62.

[0062] S3. After gravity settling, the gaseous products separated by the hydrogen-side gas-liquid separator 20 and the oxygen-side gas-liquid separator 30 are discharged from the top of the gas-liquid separator and enter the next processing step (such as drying and pressurizing collection).

[0063] S4. After gas-liquid separation, the hydrogen-side circulating alkaline solution and the oxygen-side circulating alkaline solution are re-entered into the alkaline electrolytic cell 10 for electrolysis under the action of the hydrogen-side alkaline solution circulating pump 61 and the oxygen-side alkaline solution circulating pump 62, respectively.

[0064] It should be noted that the technical solution of the present invention can cause the permeation hydrogen to undergo an electrochemical reverse reaction through catalysis, but this does not mean that all hydrogen will react with oxygen to reduce the hydrogen content in oxygen to almost zero. It only means that the hydrogen content in oxygen in the alkaline water electrolysis hydrogen production system is reduced and maintained at an industrial safety level. Example 1

[0065] Hydrogen is prepared using the alkaline electrolysis hydrogen production apparatus and method of the present invention to reduce the hydrogen content in oxygen. The third electrode 15 is disposed 2 cm away from the diaphragm. The third electrode 15 is a porous electrode with a porosity of 55%. The third electrode 15 is coated with a palladium-platinum alloy catalyst. The alkaline electrolyte is a 30% potassium hydroxide solution.

[0066] S1. Under the action of direct current, the alkaline electrolyte in the alkaline electrolyzer 10 becomes a gas-liquid mixture containing a large number of microbubbles; wherein, the anode, the third electrode 15, the load 50 and the alkaline electrolyte of the alkaline electrolyzer 10 form a fuel cell circuit on the anode side of the alkaline electrolyzer 10, so that the permeated hydrogen entering the anode side of the alkaline electrolyzer 10 undergoes an electrochemical reverse reaction, thereby achieving deep removal of hydrogen from oxygen on the anode side of the alkaline electrolyzer 10;

[0067] S2. The gas-liquid mixture on the cathode side of the alkaline electrolytic cell 10 is pumped into the hydrogen-side gas-liquid separator 20 for gas-liquid separation by the hydrogen-side alkaline circulation pump 61, and the gas-liquid mixture on the anode side of the alkaline electrolytic cell 10 is pumped into the oxygen-side gas-liquid separator 30 for gas-liquid separation by the oxygen-side alkaline circulation pump 62.

[0068] S3. After gravity settling, the gaseous products separated by the hydrogen-side gas-liquid separator 20 and the oxygen-side gas-liquid separator 30 are discharged from the top of the gas-liquid separator and enter the next processing step (such as drying and pressurizing collection).

[0069] S4. After gas-liquid separation, the hydrogen-side circulating alkaline solution and the oxygen-side circulating alkaline solution are re-entered into the alkaline electrolytic cell 10 for electrolysis under the action of the hydrogen-side alkaline solution circulating pump 61 and the oxygen-side alkaline solution circulating pump 62, respectively.

[0070] The flow rate of the mixed alkali solution at the inlet 19 was 300 ml / min. Electrolysis was performed for 100 s under a constant current of 5 A. The gas at the gas phase outlet of the oxygen-side gas-liquid separator 30 was collected, and the hydrogen content in the oxygen was measured to be 0.97%.

[0071] Comparative Example 1

[0072] Compared with Example 1, the alkaline electrolyzer in Comparative Example 1 is a conventional alkaline electrolyzer, and the alkaline electrolyte is a 30% potassium hydroxide solution. The flow rate of the mixed alkaline solution at the inlet of the mixed alkaline solution is 300 ml / min. Electrolysis is carried out for 100 s under a constant current of 5 A. The gas at the gas phase outlet of the oxygen-side gas-liquid separator is collected, and the hydrogen content in the oxygen is measured to be 2.23%.

[0073] Comparing the results of Example 1 and Comparative Example 1, it can be seen that the alkaline electrolysis hydrogen production apparatus and method of the present invention for reducing the hydrogen content in oxygen can effectively remove the permeated hydrogen on the anode side of the alkaline electrolysis cell by inserting a third electrode into the anode chamber of the alkaline electrolysis cell and connecting an external load between the third electrode and the anode of the alkaline electrolysis cell. This reduces the hydrogen content in oxygen in the alkaline water electrolysis hydrogen production system from 2.23% to 0.97%, effectively reducing the hydrogen content in oxygen in the alkaline water electrolysis hydrogen production system and ensuring that the alkaline water electrolysis hydrogen production system can operate safely and stably under fluctuating operating conditions.

[0074] It should be noted that the embodiments described above are illustrative and not intended to limit the scope of protection of this invention. For those skilled in the art, non-essential improvements and adjustments made to this invention without departing from its essence and scope still fall within the scope of protection of this invention.

Claims

1. An alkaline electrolytic hydrogen production device for reducing the hydrogen content in oxygen, comprising an alkaline electrolyzer, a hydrogen-side gas-liquid separator, a hydrogen-side alkaline solution circulation pump, an oxygen-side gas-liquid separator, and an oxygen-side alkaline solution circulation pump; Its features are, The alkaline electrolyzer has a third electrode on its anode side, and a load is externally connected between the third electrode and the anode of the alkaline electrolyzer. The third electrode, the anode of the alkaline electrolyzer, the load, and the alkaline electrolyte form a fuel cell circuit on the anode side of the alkaline electrolyzer. The alkaline electrolyzer includes a cathode plate and an anode plate, which are spaced apart and separated by a diaphragm. An anode electrode is disposed between the diaphragm and the anode plate, and the third electrode is disposed between the anode electrode and the diaphragm. A cathode electrode is disposed between the diaphragm and the cathode plate.

2. The alkaline electrolytic hydrogen production apparatus for reducing the hydrogen content in oxygen according to claim 1, characterized in that, The third electrode, anode electrode, and cathode electrode are made of the same electrode material.

3. The alkaline electrolytic hydrogen production apparatus for reducing the hydrogen content in oxygen according to claim 1, characterized in that, The third electrode is coated with a catalyst to promote the oxidation of hydrogen.

4. The alkaline electrolytic hydrogen production apparatus for reducing the hydrogen content in oxygen according to claim 3, characterized in that, The catalyst is a platinum-based catalyst or titanium dioxide.

5. The alkaline electrolytic hydrogen production apparatus for reducing the hydrogen content in oxygen according to claim 1, characterized in that, The third electrode is positioned 1-2 cm from the diaphragm.

6. The alkaline electrolytic hydrogen production apparatus for reducing the hydrogen content in oxygen according to claim 1, characterized in that, The third electrode is a porous electrode with a porosity of 40% to 70%.

7. The alkaline electrolytic hydrogen production apparatus for reducing the hydrogen content in oxygen according to claim 1, characterized in that, The third electrode is detachably inserted into the alkaline electrolytic cell.

8. The alkaline electrolytic hydrogen production apparatus for reducing the hydrogen content in oxygen according to claim 1, characterized in that, The alkaline electrolyzer has an oxygen-side gas-liquid mixed phase outlet at the top of the anode side and a hydrogen-side gas-liquid mixed phase outlet at the top of the cathode side; the alkaline electrolyzer has a mixed alkaline solution inlet at the bottom and a mixed alkaline solution inlet line at the mixed alkaline solution inlet. The hydrogen-side gas-liquid separator has a first gas-liquid mixed phase inlet in the middle, a first liquid phase outlet at the bottom, and a first gas phase outlet at the top. The oxygen-side gas-liquid separator is provided with a second gas-liquid mixed phase inlet in the middle, a second gas phase outlet at the top, and a second liquid phase outlet at the bottom. The hydrogen-side gas-liquid mixed phase outlet is connected to the first gas-liquid mixed phase inlet via a pipeline, the first liquid phase outlet is connected to the mixed alkali inlet line via a pipeline, and a first gas phase outlet line is provided at the first gas phase outlet. The oxygen-side gas-liquid mixed phase outlet is connected to the second gas-liquid mixed phase inlet via a pipeline, the second liquid phase outlet is connected to the mixed alkali inlet line via a pipeline, and a second gas phase outlet line is provided at the second gas phase outlet.

9. A method for producing hydrogen by alkaline electrolysis to reduce the hydrogen content in oxygen, characterized in that, The alkaline electrolysis hydrogen production apparatus for reducing the hydrogen content in oxygen according to any one of claims 1 to 8 includes the following steps: S1. Under the action of direct current, the alkaline electrolyte in the alkaline electrolyzer becomes a gas-liquid mixture containing a large number of microbubbles; wherein, the anode, third electrode, load and alkaline electrolyte of the alkaline electrolyzer form a fuel cell circuit on the anode side of the alkaline electrolyzer, so that the permeated hydrogen entering the anode side of the alkaline electrolyzer undergoes an electrochemical reverse reaction, thereby achieving deep removal of hydrogen from oxygen on the anode side of the alkaline electrolyzer; S2. The gas-liquid mixture on the cathode side of the alkaline electrolyzer is pumped into the hydrogen-side gas-liquid separator for gas-liquid separation by the hydrogen-side alkaline solution circulation pump, and the gas-liquid mixture on the anode side of the alkaline electrolyzer is pumped into the oxygen-side gas-liquid separator for gas-liquid separation by the oxygen-side alkaline solution circulation pump. S3. After gravity settling, the gaseous products separated by the hydrogen-side gas-liquid separator and the oxygen-side gas-liquid separator are discharged from the top of the gas-liquid separator and enter the next processing step. S4. After gas-liquid separation, the hydrogen-side circulating alkaline solution and the oxygen-side circulating alkaline solution are re-entered into the alkaline electrolytic cell for electrolysis under the action of the hydrogen-side alkaline solution circulation pump and the oxygen-side alkaline solution circulation pump, respectively.

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