Electrolysis of water to produce hydrogen

Abstract

This invention provides a water electrolysis hydrogen production device, comprising: an alkaline electrolyzer having a first electrolysis chamber, a first hydrogen outlet, and a first oxygen outlet, the first hydrogen outlet and the first oxygen outlet being respectively connected to the first electrolysis chamber; a PEM electrolyzer having a second electrolysis chamber, a second hydrogen outlet, and a second oxygen outlet, the second hydrogen outlet and the second oxygen outlet being respectively connected to the second electrolysis chamber; and a separation component having a connected hydrogen separation inlet and a hydrogen separation outlet, and a connected oxygen separation inlet and an oxygen separation outlet, the first hydrogen outlet and the second hydrogen outlet being respectively connected to the hydrogen separation inlet, and the first oxygen outlet and the second oxygen outlet being respectively connected to the oxygen separation inlet. The technical solution provided by this application can solve the problem of the alkaline electrolysis system and the PEM electrolysis system being independent of each other in related technologies.

Description

Technical Field

[0001] This invention relates to the field of hydrogen production technology, and more specifically, to a hydrogen production apparatus by water electrolysis. Background Technology

[0002] Hydrogen energy is a green, low-carbon, and widely applicable secondary energy source that can be widely used in various energy sectors to achieve low-carbon development in industry, construction, transportation, and other fields. Electrolysis of water is currently the most environmentally friendly hydrogen production technology. Current technologies include alkaline electrolyzers, PEM electrolyzers, solid oxide electrolyzers, and anion exchange membrane electrolyzers.

[0003] Alkaline water electrolysis for hydrogen production uses alkaline solution as the electrolyte and a porous membrane as the diaphragm. It operates at temperatures between 80℃ and 90℃ and is suitable for stable conditions. However, under fluctuating loads from new energy sources, the purity of hydrogen and oxygen gas may fail to meet standards, leading to system tripping. PEM water electrolysis uses pure water as the electrolyte and a non-porous membrane as the diaphragm. It operates at temperatures between 50℃ and 80℃ and can operate under fluctuating loads from new energy sources, with a load fluctuation range of 5% to 150%. However, it is significantly more expensive, costing approximately 3 to 5 times more than alkaline water electrolysis for hydrogen production.

[0004] To address the issue of renewable energy power consumption, the current industry practice is to configure two electrolysis systems simultaneously when producing hydrogen on a large scale from renewable energy sources. However, these two electrolysis systems are currently configured separately and independently, resulting in poor operational flexibility. Summary of the Invention

[0005] This invention provides a water electrolysis hydrogen production device to solve the problem of the alkaline electrolysis system and the PEM electrolysis system being independent in related technologies.

[0006] This invention provides a water electrolysis hydrogen production device, comprising: an alkaline electrolyzer having a first electrolysis chamber, a first hydrogen outlet, and a first oxygen outlet, the first hydrogen outlet and the first oxygen outlet being respectively connected to the first electrolysis chamber; a PEM electrolyzer having a second electrolysis chamber, a second hydrogen outlet, and a second oxygen outlet, the second hydrogen outlet and the second oxygen outlet being respectively connected to the second electrolysis chamber; and a separation component having a connected hydrogen separation inlet and a hydrogen separation outlet, and a connected oxygen separation inlet and an oxygen separation outlet, the first hydrogen outlet and the second hydrogen outlet being respectively connected to the hydrogen separation inlet, and the first oxygen outlet and the second oxygen outlet being respectively connected to the oxygen separation inlet.

[0007] Furthermore, the separation assembly includes a hydrogen separator and a hydrogen scrubber connected in series. The hydrogen scrubber is located downstream of the hydrogen separator. The hydrogen separation inlet includes a first separation inlet provided in the hydrogen separator and a first washing inlet provided in the hydrogen scrubber. A first hydrogen outlet is connected to the first separation inlet, and a second hydrogen outlet is connected to the first washing inlet. The hydrogen separation outlet is located in the hydrogen scrubber. The separation assembly also includes an oxygen separator and an oxygen scrubber connected in series. The oxygen scrubber is located downstream of the oxygen separator. The oxygen separation inlet includes a second separation inlet provided in the oxygen separator and a second washing inlet provided in the oxygen scrubber. A first oxygen outlet is connected to the second separation inlet, and a second oxygen outlet is connected to the second washing inlet. The oxygen separation outlet is located in the oxygen scrubber.

[0008] Furthermore, the hydrogen scrubber also has a first separation liquid outlet, and the hydrogen separator also has a first separation liquid inlet, with the first separation liquid outlet and the first separation liquid inlet connected together; the oxygen scrubber also has a second separation liquid outlet, and the oxygen separator also has a second separation liquid inlet, with the second separation liquid outlet and the second separation liquid inlet connected together.

[0009] Furthermore, the water electrolysis hydrogen production device also includes a filter with a filter inlet and a filter outlet, the filter outlet being connected to the first electrolysis chamber; the hydrogen separator also has a first circulation outlet connected to the first separation liquid inlet, the first circulation outlet being connected to the filter inlet; the oxygen separator also has a second circulation outlet connected to the second separation liquid inlet, the second circulation outlet being connected to the filter inlet.

[0010] Furthermore, the pressure in an alkaline electrolyzer is lower than that in a PEM electrolyzer.

[0011] Furthermore, the water electrolysis hydrogen production unit also includes a hydrogen cooler, which is located downstream of the separation component and is connected to the hydrogen separation outlet.

[0012] Furthermore, the water electrolysis hydrogen production device also includes a hydrogen purifier, which is located downstream of the hydrogen cooler and is connected to the hydrogen cooler.

[0013] Furthermore, the water electrolysis hydrogen production unit also includes an oxygen cooler, which is located downstream of the separation component and is connected to the oxygen separation outlet.

[0014] Furthermore, the water electrolysis hydrogen production unit also includes an oxygen purifier, which is located downstream of the oxygen cooler and is connected to the oxygen cooler.

[0015] Furthermore, the water electrolysis hydrogen production unit also includes a supplementary water tank connected to the PEM electrolyzer.

[0016] The water electrolysis hydrogen production device of this invention includes an alkaline electrolyzer, a PEM electrolyzer, and a separation assembly. Hydrogen produced in the first electrolysis chamber of the alkaline electrolyzer enters the hydrogen separation inlet of the separation assembly through the first hydrogen outlet for separation. Oxygen produced in the first electrolysis chamber enters the oxygen separation inlet of the separation assembly through the first oxygen outlet for separation. Similarly, hydrogen produced in the second electrolysis chamber of the PEM electrolyzer enters the hydrogen separation inlet of the separation assembly through the second hydrogen outlet for separation. Oxygen produced in the second electrolysis chamber enters the oxygen separation inlet of the separation assembly through the second oxygen outlet for separation. This water electrolysis hydrogen production device combines the high energy efficiency of alkaline water electrolysis with the wide adaptability to fluctuations of PEM water electrolysis. Furthermore, the use of the same separation assembly improves operational flexibility. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0018] Figure 1 A schematic diagram of a water electrolysis hydrogen production apparatus provided according to an embodiment of the present invention is shown.

[0019] The above figures include the following reference numerals:

[0020] 10. Alkaline electrolytic cell;

[0021] 20. PEM electrolytic cell;

[0022] 30. Separation assembly; 31. Hydrogen separator; 311. First separation inlet; 32. Hydrogen scrubber; 312. First scrubbing inlet; 33. Oxygen separator; 331. Second separation inlet; 34. Oxygen scrubber; 341. Second scrubbing inlet;

[0023] 40. Filter; 41. Water replenishment tank;

[0024] 50. Hydrogen cooler; 51. Hydrogen purifier;

[0025] 60. Oxygen cooler; 61. Oxygen purifier. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. 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 protection of the present invention.

[0027] like Figure 1 As shown, this embodiment of the invention provides a water electrolysis hydrogen production device, which includes an alkaline electrolyzer 10, a PEM electrolyzer 20, and a separation component 30. The alkaline electrolyzer 10 has a first electrolysis chamber, a first hydrogen outlet, and a first oxygen outlet, which are respectively connected to the first electrolysis chamber. The PEM electrolyzer 20 has a second electrolysis chamber, a second hydrogen outlet, and a second oxygen outlet, which are respectively connected to the second electrolysis chamber. The separation component 30 has a connected hydrogen separation inlet and a hydrogen separation outlet, and a connected oxygen separation inlet and an oxygen separation outlet. The first hydrogen outlet and the second hydrogen outlet are respectively connected to the hydrogen separation inlet, and the first oxygen outlet and the second oxygen outlet are respectively connected to the oxygen separation inlet.

[0028] The water electrolysis hydrogen production device of this invention includes an alkaline electrolyzer 10, a PEM electrolyzer 20, and a separation component 30. Hydrogen produced in the first electrolysis chamber of the alkaline electrolyzer 10 enters the hydrogen separation inlet of the separation component 30 through the first hydrogen outlet for separation. Oxygen produced in the first electrolysis chamber enters the oxygen separation inlet of the separation component 30 through the first oxygen outlet for separation. Hydrogen produced in the second electrolysis chamber of the PEM electrolyzer 20 enters the hydrogen separation inlet of the separation component 30 through the second hydrogen outlet for separation. Oxygen produced in the second electrolysis chamber enters the oxygen separation inlet of the separation component 30 through the second oxygen outlet for separation. This water electrolysis hydrogen production device combines the high energy efficiency of alkaline water electrolysis with the wide adaptability to fluctuations of PEM water electrolysis. Furthermore, the use of the same separation component 30 improves operational flexibility.

[0029] The water electrolysis hydrogen production device in this embodiment can couple alkaline water electrolysis and PEM water electrolysis systems together, which not only improves system energy efficiency but also saves initial investment and broadens the load fluctuation adaptability range of new energy sources.

[0030] like Figure 1As shown, the separation assembly 30 includes a hydrogen separator 31 and a hydrogen scrubber 32 connected to each other. The hydrogen scrubber 32 is located downstream of the hydrogen separator 31. The hydrogen separation inlet includes a first separation inlet 311 disposed in the hydrogen separator 31 and a first scrubbing inlet 312 disposed in the hydrogen scrubber 32. A first hydrogen outlet is connected to the first separation inlet 311, and a second hydrogen outlet is connected to the first scrubbing inlet 312. The hydrogen separation outlet is disposed in the hydrogen scrubber 32. The hydrogen separator 31 can be used to separate the alkaline solution and hydrogen in the alkaline electrolysis cell 10 into a gas-liquid mixture. The hydrogen scrubber 32 can further separate the residual alkaline solution to obtain pure hydrogen.

[0031] The hydrogen scrubber 32 can be used to separate the electrolyte and hydrogen in the PEM electrolyzer 20.

[0032] like Figure 1 As shown, the separation assembly 30 includes an oxygen separator 33 and an oxygen scrubber 34 connected in series. The oxygen scrubber 34 is located downstream of the oxygen separator 33. The oxygen separation inlet includes a second separation inlet 331 disposed in the oxygen separator 33 and a second scrubbing inlet 341 disposed in the oxygen scrubber 34. A first oxygen outlet is connected to the second separation inlet 331, and a second oxygen outlet is connected to the second scrubbing inlet 341. The oxygen separation outlet is disposed in the oxygen scrubber 34. The oxygen separator 33 can be used to separate the alkaline solution and oxygen in the alkaline electrolytic cell 10 into a gas-liquid mixture. The oxygen scrubber 34 can further separate the residual alkaline solution to obtain pure oxygen.

[0033] like Figure 1 As shown, the hydrogen scrubber 32 also has a first separation liquid outlet, and the hydrogen separator 31 also has a first separation liquid inlet, with the first separation liquid outlet and the first separation liquid inlet connected together. The electrolyte separated in the hydrogen scrubber 32 from the PEM electrolyzer 20 can neutralize the electrolyte separated in the hydrogen separator 31 from the alkaline electrolyzer 10.

[0034] like Figure 1 As shown, the oxygen scrubber 34 also has a second separation liquid outlet, and the oxygen separator 33 also has a second separation liquid inlet, with the second separation liquid outlet and the second separation liquid inlet connected together. The electrolyte separated in the oxygen scrubber 34 by the PEM electrolyzer 20 can neutralize the electrolyte separated in the oxygen separator 33 by the alkaline electrolyzer 10.

[0035] like Figure 1As shown, the water electrolysis hydrogen production device also includes a filter 40, which has a filter inlet and a filter outlet. The filter outlet is connected to the first electrolysis chamber. The hydrogen separator 31 also has a first circulation outlet connected to the first separation liquid inlet, which is connected to the filter inlet. The oxygen separator 33 also has a second circulation outlet connected to the second separation liquid inlet, which is connected to the filter inlet. By leading the alkaline electrolyte and the neutralized electrolyte from the hydrogen separator 31 and the oxygen separator 33 to the filter 40, the electrolyte can be filtered and then recycled into the alkaline electrolysis tank 10.

[0036] The pressure in the alkaline electrolytic cell 10 is lower than that in the PEM electrolytic cell 20. This configuration prevents the electrolyte in the PEM electrolytic cell 20 from entering the alkaline electrolytic cell 10, thereby preventing acid-base neutralization between the electrolyte in the alkaline electrolytic cell 10 and the electrolyte in the PEM electrolytic cell 20.

[0037] In this embodiment, the electrolyte in the PEM electrolyzer 20 is acidic.

[0038] like Figure 1 As shown, the water electrolysis hydrogen production device also includes a hydrogen cooler 50, which is located downstream of the separation component 30 and is connected to the hydrogen separation outlet. The hydrogen cooler 50 can be used to cool the hydrogen.

[0039] like Figure 1 As shown, the water electrolysis hydrogen production device also includes a hydrogen purifier 51, which is located downstream of the hydrogen cooler 50 and is connected to the hydrogen cooler 50. The hydrogen purifier 51 can purify the hydrogen.

[0040] like Figure 1 As shown, the water electrolysis hydrogen production unit also includes an oxygen cooler 60, which is located downstream of the separation component 30 and is connected to the oxygen separation outlet. The oxygen cooler 60 is used to cool the oxygen.

[0041] like Figure 1 As shown, the water electrolysis hydrogen production device also includes an oxygen purifier 61, which is located downstream of the oxygen cooler 60 and is connected to the oxygen cooler 60. The oxygen purifier 61 can purify oxygen.

[0042] like Figure 1 As shown, the water electrolysis hydrogen production device also includes a replenishment water tank 41 connected to the PEM electrolyzer 20. The replenishment water tank 41 allows water to be added to the PEM electrolyzer 20, enabling the PEM electrolyzer 20 to operate continuously.

[0043] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0044] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0045] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms 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, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0046] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0047] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0048] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An apparatus for producing hydrogen by electrolysis of water, characterized by comprising: The water electrolysis hydrogen production device includes: An alkaline electrolytic cell (10) has a first electrolysis chamber, a first hydrogen outlet and a first oxygen outlet, wherein the first hydrogen outlet and the first oxygen outlet are respectively connected to the first electrolysis chamber; The PEM electrolyzer (20) has a second electrolysis chamber, a second hydrogen outlet and a second oxygen outlet, wherein the second hydrogen outlet and the second oxygen outlet are respectively connected to the second electrolysis chamber; The separation component (30) has a hydrogen separation inlet and a hydrogen separation outlet connected to each other, and an oxygen separation inlet and an oxygen separation outlet connected to each other. The first hydrogen outlet and the second hydrogen outlet are respectively connected to the hydrogen separation inlet, and the first oxygen outlet and the second oxygen outlet are respectively connected to the oxygen separation inlet. The separation assembly (30) includes a hydrogen separator (31) and a hydrogen scrubber (32) connected in series. The hydrogen scrubber (32) is located downstream of the hydrogen separator (31). The hydrogen separation inlet includes a first separation inlet (311) disposed in the hydrogen separator (31) and a first scrubbing inlet (312) disposed in the hydrogen scrubber (32). The first hydrogen outlet is connected to the first separation inlet (311), and the second hydrogen outlet is connected to the first scrubbing inlet (312). The hydrogen separation outlet is disposed in the hydrogen scrubber (32). The separation component (30) includes an oxygen separator (33) and an oxygen scrubber (34) connected in series. The oxygen scrubber (34) is located downstream of the oxygen separator (33). The oxygen separation inlet includes a second separation inlet (331) disposed in the oxygen separator (33) and a second scrubbing inlet (341) disposed in the oxygen scrubber (34). The first oxygen outlet is connected to the second separation inlet (331), and the second oxygen outlet is connected to the second scrubbing inlet (341). The oxygen separation outlet is disposed in the oxygen scrubber (34).

2. The water electrolysis hydrogen production apparatus according to claim 1, characterized in that, The hydrogen scrubber (32) also has a first separation liquid outlet, and the hydrogen separator (31) also has a first separation liquid inlet, the first separation liquid outlet and the first separation liquid inlet being connected; The oxygen scrubber (34) also has a second separation liquid outlet, and the oxygen separator (33) also has a second separation liquid inlet, the second separation liquid outlet and the second separation liquid inlet being connected.

3. The water electrolysis hydrogen generator according to claim 2, characterized in that, The water electrolysis hydrogen production device further includes a filter (40), which has a filter inlet and a filter outlet, and the filter outlet is connected to the first electrolysis chamber. The hydrogen separator (31) also has a first circulation outlet connected to the first separation liquid inlet, and the first circulation outlet is connected to the filter inlet; The oxygen separator (33) also has a second circulation outlet connected to the second separation liquid inlet, and the second circulation outlet is connected to the filter inlet.

4. The water electrolysis hydrogen generator of claim 1, wherein, The pressure of the alkaline electrolytic cell (10) is less than the pressure of the PEM electrolytic cell (20).

5. The water electrolysis hydrogen generator of claim 1, wherein, The water electrolysis hydrogen production device also includes a hydrogen cooler (50), which is located downstream of the separation component (30) and is connected to the hydrogen separation outlet.

6. The water electrolysis hydrogen generator according to claim 5, characterized in that, The water electrolysis hydrogen production device also includes a hydrogen purifier (51), which is located downstream of the hydrogen cooler (50) and is connected to the hydrogen cooler (50).

7. The water electrolysis hydrogen generator of claim 1, wherein, The water electrolysis hydrogen production device also includes an oxygen cooler (60), which is located downstream of the separation component (30) and is connected to the oxygen separation outlet. 8.The water electrolysis hydrogen generation device according to claim 7, characterized in that, The water electrolysis hydrogen production device also includes an oxygen purifier (61), which is located downstream of the oxygen cooler (60) and is connected to the oxygen cooler (60).

9. The water electrolysis hydrogen production apparatus according to claim 1, characterized in that, The water electrolysis hydrogen production device also includes a supplementary water tank (41) connected to the PEM electrolyzer (20).

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