Alkaline water electrolysis hydrogen production system

Abstract

The utility model discloses an alkaline water electrolysis hydrogen production system, and belongs to the technical field of water electrolysis hydrogen production, the alkaline water electrolysis hydrogen production system comprises an electrolytic bath, two groups of separation return pipelines, two water supplementing separation tanks and a first driving part, and the electrolytic bath is provided with two outlets; the two groups of separation return pipelines are respectively communicated with the two outlets, and are used for gas-liquid separation and liquid return to the electrolytic bath; the two water supplementing separation tanks are connected to the ends, away from the electrolytic bath, of the two sets of separation backflow pipelines correspondingly, and gas outlets are formed in the highest positions of the water supplementing separation tanks; the first driving part is communicated with the water supplementing and separating tank and the separating and returning pipeline, and the first driving part responds to the first driving force to convey liquid in the water supplementing and separating tank to the separating and returning pipeline. According to the alkaline water electrolysis hydrogen production system, alkali liquor circulation can be achieved, and zero emission of an alkali-containing solution in the water electrolysis hydrogen production process is guaranteed.

Description

Technical Field

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

[0002] Hydrogen production by water electrolysis refers to the process where water molecules are dissociated under the influence of direct current to generate oxygen and hydrogen, which are then released from the anode and cathode of the electrolyzer, respectively. Depending on the membrane material used in the electrolyzer, hydrogen production by water electrolysis is generally classified into alkaline water electrolysis (ALK), proton exchange membrane (PEM) water electrolysis, high-temperature solid oxide water electrolysis (SOEC), and polymer anion exchange membrane (AEM) water electrolysis. Among these, alkaline water electrolysis is the earliest industrialized water electrolysis technology, with decades of application experience, and is the most mature and widely used form in the domestic market.

[0003] Currently, alkaline water electrolysis hydrogen production systems mainly consist of four parts: the electrolyzer, the circulation system, the purification system, and the electrical control system. However, during the operation of the circulation system, some alkaline solution is discharged, causing inconvenience. Utility Model Content

[0004] The main purpose of this application is to provide an alkaline water electrolysis hydrogen production system, which aims to solve the problem that current alkaline water electrolysis hydrogen production systems discharge alkaline solutions.

[0005] To achieve the above objectives, this application provides an alkaline water electrolysis hydrogen production system, which includes an electrolyzer, two sets of separation reflux pipelines, two water replenishment separation tanks, and a first drive unit. The electrolyzer has two outlets; the two sets of separation reflux pipelines are respectively connected to the two outlets, and the separation reflux pipelines are used for gas-liquid separation and return liquid to the electrolyzer; the two water replenishment separation tanks are respectively connected to the ends of the two sets of separation reflux pipelines away from the electrolyzer; the first drive unit connects the water replenishment separation tanks and the separation reflux pipelines, and the first drive unit responds to a first driving force to transport the liquid in the water replenishment separation tanks to the separation reflux pipelines.

[0006] Optionally, the lowest points of the two water replenishment tanks are connected by a first pipeline.

[0007] Optionally, a second pipeline is connected between the two water replenishment tanks, and the second pipeline is connected to the separation return pipeline through a third pipeline; wherein, the first drive unit is disposed on the third pipeline.

[0008] Optionally, the water electrolysis hydrogen production system further includes a baffle plate, which is disposed in the connection area between the water replenishment tank and the separation return pipeline and is located inside the water replenishment tank.

[0009] Optionally, the separation reflux pipeline includes a separation tank, a scrubber, a heat exchanger, a secondary separation tank, and a liquid collector connected in sequence; wherein, the separation tank is connected to one of the outlets, and the liquid collector is connected to the makeup water separation tank.

[0010] Optionally, both the washer and the heat exchanger are provided with a reflux pipe that communicates with the separation tank.

[0011] Optionally, a solenoid valve is installed on the connecting pipeline between the liquid collector and the water replenishment separator.

[0012] Optionally, the first drive unit is connected to the washer.

[0013] Optionally, the water replenishment tank is also connected to an external pure water pipe.

[0014] Optionally, the electrolyzer also has an inlet; the water electrolysis hydrogen production system further includes an alkaline heat exchanger and a second drive unit, the alkaline heat exchanger connecting the two separation tanks and the inlet; the second drive unit is disposed on the pipeline connecting the alkaline heat exchanger and the inlet, and the second drive unit responds to a second driving force to transport the liquid in the alkaline heat exchanger to the electrolyzer.

[0015] This application proposes an alkaline water electrolysis hydrogen production system. The oxygen-containing electrolyte and hydrogen-containing electrolyte produced in the electrolyzer are discharged from two separate outlets. The electrolyte is an alkaline solution. Taking the outlet for the hydrogen-containing electrolyte, along with its corresponding separation reflux pipeline and first drive unit, as an example, the hydrogen-containing electrolyte undergoes gas-liquid separation upon reaching the separation reflux pipeline. Most of the alkaline solution separated by the separation reflux pipeline is then returned to the electrolyzer, while a small amount is discharged to a water replenishment tank. A small amount of hydrogen gas mixed in the alkaline solution is discharged from the gas outlet of the water replenishment tank. The first drive unit then transports the alkaline solution from the water replenishment tank back to the separation reflux pipeline, which in turn transports the alkaline solution back to the electrolyzer, thus achieving alkaline solution circulation and ensuring zero discharge of alkaline solution during the water electrolysis hydrogen production process. Attached Figure Description

[0016] To more clearly illustrate the prior art and the present invention, the accompanying drawings used in the description of the prior art and the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other drawings from the provided drawings without any creative effort.

[0017] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which this utility model can be implemented. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and purposes that this utility model can produce, should still fall within the scope of the technical content disclosed in this utility model.

[0018] Figure 1 This is a schematic diagram of the overall structure of an alkaline water electrolysis hydrogen production system proposed in an embodiment of this application.

[0019] In the diagram: 1. Electrolytic cell; 2. Water replenishment tank; 3. First drive unit; 41. Separation tank; 42. Scrubber; 43. Heat exchanger; 44. Secondary separation tank; 45. Liquid collector; 5. Alkali heat exchanger; 6. Second drive unit; 7. Baffle plate.

[0020] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0023] In this utility model, unless otherwise explicitly specified and limited, the terms "connection" and "fixation" should be interpreted broadly. For example, "fixation" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0024] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0025] The present application will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] Figure 1 This is a schematic diagram of the overall structure of an alkaline water electrolysis hydrogen production system proposed in an embodiment of this application.

[0027] refer to Figure 1 This application provides an alkaline water electrolysis hydrogen production system, which may include an electrolyzer 1, two sets of separation and reflux pipelines, two water replenishment separation tanks 2, and a first drive unit 3. The electrolyzer 1 has two outlets; the two sets of separation and reflux pipelines are respectively connected to the two outlets, and the separation and reflux pipelines are used for gas-liquid separation and return liquid to the electrolyzer 1; the two water replenishment separation tanks 2 are respectively connected to the ends of the two sets of separation and reflux pipelines away from the electrolyzer 1, wherein the highest point of the water replenishment separation tank 2 is provided with a gas outlet; the first drive unit 3 connects the water replenishment separation tank 2 and the separation and reflux pipelines, and the first drive unit 3 responds to a first driving force to transport the liquid in the water replenishment separation tank 2 to the separation and reflux pipelines.

[0028] This application proposes an alkaline water electrolysis hydrogen production system. The oxygen-containing electrolyte and hydrogen-containing electrolyte produced in the electrolyzer 1 are discharged from two separate outlets. The electrolyte is an alkaline solution. Taking the outlet for the hydrogen-containing electrolyte, the corresponding separation reflux pipeline, and the first drive unit 3 as examples, the hydrogen-containing electrolyte reaches the separation reflux pipeline for gas-liquid separation. Most of the alkaline solution separated by the separation reflux pipeline is then returned to the electrolyzer 1, while the remaining small amount is discharged to the water replenishment tank 2. The small amount of hydrogen gas mixed in the alkaline solution is discharged from the gas outlet of the water replenishment tank 2. The first drive unit 3 then transports the alkaline solution in the water replenishment tank 2 back to the separation reflux pipeline, which in turn transports the alkaline solution back to the electrolyzer 1, thus achieving alkaline solution circulation and ensuring zero discharge of alkaline solution during the water electrolysis hydrogen production process.

[0029] It should be understood that the first drive unit 3 is connected to both water replenishment separation tanks 2, so that the first drive unit 3 can transport the alkaline solution in both water replenishment separation tanks 2 back to the separation return pipeline.

[0030] In an exemplary embodiment, a second pipeline is connected between the two water replenishment separation tanks 2, and the second pipeline is connected to the separation return pipeline through a third pipeline; wherein, the first drive unit 3 is disposed on the third pipeline.

[0031] The first drive unit 3 can be a first water pump. The first driving force is provided to the first water pump by an external power source. When the first water pump is working, it simultaneously draws alkaline solution from the two water replenishment separation tanks 2 and transports it to the separation return pipeline, thereby realizing the circulation of alkaline solution.

[0032] Furthermore, the two water replenishment separation tanks 2 should be set on the same horizontal plane, and the lowest points of the two water replenishment separation tanks 2 should be connected through the first pipeline. In this way, the first pipeline can maintain the liquid level balance in the two water replenishment separation tanks 2, so that when the first water pump simultaneously draws alkaline solution from the two water replenishment separation tanks 2, the alkaline solution in one of the water replenishment separation tanks 2 will not be drawn out prematurely, thus ensuring that the first water pump can work normally.

[0033] In an exemplary embodiment, an external pure water pipe is also connected to a water replenishment tank 2.

[0034] Specifically, pure water can be added to the water replenishment tank 2 through the pure water pipeline. In this way, the pure water and alkaline solution can be transported to the separation return pipeline by the first water pump and flow back into the electrolyzer 1 to complete the water replenishment work of the water electrolysis hydrogen production system. At the same time, the alkaline solution in the water replenishment tank can be further diluted.

[0035] Furthermore, since the liquid levels of the two water replenishment tanks 2 are balanced, only one external pure water pipe needs to be connected to the outside of one water replenishment tank 2. The external pure water pipe can be found by referring to... Figure 1 Purified water inlet.

[0036] In addition, pure water is added to the water replenishment tank 2 through an external pure water pipe, so that the liquid level in the water replenishment tank 2 is maintained within a certain range. This isolates the small amount of hydrogen or oxygen discharged from the water replenishment tank 2, preventing a small amount of hydrogen and oxygen from mixing and causing danger through the pipes that maintain the liquid level balance between the two water replenishment tanks 2, thus ensuring the safety of the system.

[0037] Of course, in an optional embodiment, an automatic liquid level monitoring device can be installed in a water replenishment tank 2. The automatic liquid level monitoring device is electrically connected to the background system. The background system sets a liquid level height range. When the liquid level height is lower than the set range, the background system controls the external pure water pipeline to replenish pure water into the water replenishment tank 2.

[0038] In an exemplary embodiment, the water electrolysis hydrogen production system may further include a baffle plate 7, which is disposed in the connection area between the water replenishment separator 2 and the separation return pipeline and is located inside the water replenishment separator 2.

[0039] Specifically, the alkaline solution and gas mixture entering the water replenishment separator 2 washes the baffle plate 7. Due to the difference in inertia, most of the alkaline solution falls into the water replenishment separator 2, while the gas floats above the interior of the water replenishment separator 2 and is discharged, thereby further separating the alkaline solution and the gas.

[0040] In an exemplary embodiment, the separation return pipeline may include a separation tank 41, a scrubber 42, a heat exchanger 43, a secondary separation tank 44, and a liquid collector 45 connected in sequence; wherein, the separation tank 41 is connected to an outlet, and the liquid collector 45 is connected to the water replenishment separation tank 2.

[0041] Specifically, taking the outlet of the hydrogen-containing electrolyte discharge and its corresponding separation reflux pipeline and water replenishment tank 2 as an example, the other outlet is similar; the hydrogen-containing electrolyte first enters the separation tank 41 for preliminary separation of hydrogen and alkali. The separated hydrogen contains a lot of alkali. Then the hydrogen enters the scrubber 42 to wash away the alkali contained in the hydrogen. The washed hydrogen is saturated water hydrogen, which still contains some alkali. Then the saturated water hydrogen enters the heat exchanger 43 for cooling. The cooled hydrogen enters the secondary separation tank 44 to further separate the water contained in the hydrogen. The separated alkali solution flows to the collector 45. Then the alkali solution in the collector 45 enters the water replenishment tank 2 for alkali circulation.

[0042] In an exemplary embodiment, a solenoid valve is provided on the connecting pipeline between the liquid collector 45 and the water replenishment tank 2, so that when the alkaline solution in the liquid collector 45 is full, it can be introduced into the water replenishment tank 2 all at once, making it easier to control the liquid level in the water replenishment tank 2.

[0043] In an exemplary embodiment, both the scrubber 42 and the heat exchanger 43 are provided with reflux pipes that communicate with the separator 41.

[0044] Specifically, the alkaline solution generated by the washing machine 42 and the alkaline solution generated by the cooling gas of the heat exchanger 43 can both be returned to the separator 41 through the return pipe.

[0045] In an exemplary embodiment, the electrolyzer 1 further has an inlet; the water electrolysis hydrogen production system may also include an alkaline heat exchanger 5 and a second drive unit 6, the alkaline heat exchanger 5 connecting two separation tanks 41 and the inlet; the second drive unit 6 is disposed on the pipeline connecting the alkaline heat exchanger 5 and the inlet, and the second drive unit 6, in response to a second driving force, transports the liquid in the alkaline heat exchanger 5 to the electrolyzer 1.

[0046] The second drive unit 6 can be a second water pump. The second driving force is provided to the second water pump by an external power source. The alkaline solution separated from the two separation tanks 41, as well as the alkaline solution returned from the scrubber 42 and heat exchanger 43, can all be returned to the alkaline heat exchanger 5 and transported back to the electrolytic cell 1 by the second water pump to complete the alkaline solution circulation and ensure zero discharge of alkaline solution during the water electrolysis hydrogen production process.

[0047] In addition, since the second water pump is connected to the electrolytic cell 1, the second water pump can also serve as the power source for the hydrogen-containing electrolyte or oxygen-containing electrolyte in the electrolytic cell 1 to flow into the separation tank 41. In other words, the second water pump can drive the hydrogen-containing electrolyte or oxygen-containing electrolyte in the electrolytic cell 1 to flow into the separation tank 41.

[0048] The first drive unit 3 is connected to the scrubber 42, which can also be understood as the second pipeline being connected to a scrubber 42. In this way, the pure water containing a trace amount of alkaline solution in the water replenishment separation tank 2 can be introduced into the scrubber 42 as washing water and then flowed back to the separation tank 41, the alkaline heat exchanger 5 and the electrolytic cell 1 in sequence.

[0049] In summary, the alkaline solutions generated by the separation tank 41, scrubber 42, and heat exchanger 43 in the separation reflux pipeline are all returned to the electrolytic cell 1. The alkaline solutions generated in the secondary separation tank 44 are collected in the liquid collector 45 and discharged into the makeup water separation tank 2. Finally, the first water pump passes the alkaline solutions in the makeup water separation tank 2 into a scrubber 42, and then back into the electrolytic cell 1. In this way, the alkaline solutions in the alkaline water electrolysis hydrogen production system are constantly circulated, and no alkaline solutions are discharged.

[0050] The overall working principle of this application is as follows:

[0051] Hydrogen side: Hydrogen gas is generated in electrolytic cell 1. The hydrogen gas mixed with electrolyte enters the separator 41. The hydrogen gas passes through the scrubber 42 and enters the heat exchanger 43. The alkaline solution generated in the separator 41, scrubber 42 and heat exchanger 43 flows back into the electrolytic cell 1. After cooling, the hydrogen gas enters the secondary separator 44. After passing through the secondary separator 44, part of the alkaline solution enters the collector 45. After the alkaline solution in the collector 45 is full, the control valve discharges the alkaline solution into the makeup water separator 2. The small amount of hydrogen gas remaining in the makeup water separator 2 is discharged through the gas outlet.

[0052] Oxygen side: Oxygen is generated in electrolytic cell 1. The oxygen mixed with electrolyte enters the separator 41. The oxygen passes through the scrubber 42 and enters the heat exchanger 43. The alkaline solution generated in the separator 41, scrubber 42 and heat exchanger 43 flows back into the electrolytic cell 1. After cooling, the oxygen enters the secondary separator 44. After passing through the secondary separator 44, part of the alkaline solution enters the collector 45. After the alkaline solution in the collector 45 is full, the control valve discharges the alkaline solution into the makeup water separator 2. The small amount of oxygen remaining in the makeup water separator 2 is discharged through the gas outlet.

[0053] Afterwards, the first water pump can transport the alkaline solution in the two water replenishment separation tanks 2 to the scrubber 42 for washing water and finally return it to the electrolytic cell 1.

[0054] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. An alkaline water electrolysis hydrogen production system, characterized by, The application relates to a water electrolysis hydrogen production system. The water electrolysis hydrogen production system comprises: an electrolytic tank (1) having two outlets; two sets of separation return pipelines respectively communicating with the two outlets, the separation return pipelines being used for gas-liquid separation and liquid return to the electrolytic tank (1); two water replenishing separation tanks (2) respectively connected to one ends of the two sets of separation return pipelines away from the electrolytic tank (1); 2. The water electrolysis hydrogen generation system of claim 1, wherein, a first driving part (3) communicating the water replenishing separation tank (2) with the separation return pipeline, the first driving part (3) being used for conveying liquid in the water replenishing separation tank (2) to the separation return pipeline in response to a first driving force.

3. The water electrolysis hydrogen generation system of claim 1, wherein, The lowest points of the two water replenishing separation tanks (2) are communicated through a first pipeline. A second pipeline is further communicated between the two water replenishing separation tanks (2), the second pipeline being communicated with the separation return pipeline through a third pipeline; 4. The water electrolysis hydrogen generation system of claim 1, wherein, wherein the first driving part (3) is arranged on the third pipeline. The water electrolysis hydrogen production system further comprises:

5. The water electrolysis hydrogen generation system of claim 1, wherein, a liquid blocking plate (7) arranged in a connecting area of the water replenishing separation tank (2) and the separation return pipeline and located in the water replenishing separation tank (2). The separation return pipeline comprises a separation tank (41), a scrubber (42), a heat exchanger (43), a secondary separation tank (44) and a liquid collector (45) communicated in sequence; 6. The water electrolysis hydrogen generation system of claim 5, wherein, wherein the separation tank (41) is communicated with one of the outlets, and the liquid collector (45) is communicated with the water replenishing separation tank (2).

7. The water electrolysis hydrogen generation system of claim 5, wherein, The scrubber (42) and the heat exchanger (43) are both provided with a return pipeline communicated with the separation tank (41).

8. The water electrolysis hydrogen generation system of claim 5, wherein, An electromagnetic valve is arranged on a communicating pipeline of the liquid collector (45) and the water replenishing separation tank (2).

9. The water electrolysis hydrogen generation system of claim 1, wherein, The first driving part (3) is communicated with the scrubber (42).

10. The water electrolysis hydrogen generation system of claim 1, wherein, An external pure water pipeline is further communicated at one of the water replenishing separation tanks (2). The electrolytic tank (1) further has an inlet; and the water electrolysis hydrogen production system further comprises: an alkali heat exchanger (5) communicating the two separation tanks (41) with the inlet; a second driving part (6) arranged on a pipeline communicating the alkali heat exchanger (5) with the inlet, the second driving part (6) being used for conveying liquid in the alkali heat exchanger (5) to the electrolytic tank (1) in response to a second driving force.

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