Alkaline water electrolysis hydrogen production system and control method thereof

Abstract

The invention relates to an alkaline water electrolysis hydrogen production system and a control method thereof. The alkaline electrolysis water hydrogen production system comprises a gas-liquid separation assembly; an outlet of the alkaline electrolytic bath is communicated with an inlet of the gas-liquid separation assembly; the hot lye tank is communicated with the first outlet of the gas-liquid separation assembly; the first circulating pump is communicated between the gas-liquid separation assembly and the hot lye tank; the first three-way valve is connected to an outlet of the hot lye tank, an outlet of the cold lye tank and a first inlet of the alkaline electrolytic tank; the second circulating pump is communicated between the first three-way valve and the alkaline electrolytic bath; the controller is used for controlling the first three-way valve to be switched to a first working state or a second working state, when the first three-way valve is in the first working state, the outlet of the hot lye tank is communicated with the first inlet of the alkaline electrolytic tank, and when the first three-way valve is in the second working state, the outlet of the hot lye tank is communicated with the second inlet. And the outlet of the cold lye tank is communicated with the first inlet of the alkaline electrolytic tank.

Description

Technical Field

[0001] The present application relates to the technical field of hydrogen production, and in particular to an alkaline water electrolysis hydrogen production system and a control method thereof. Background Art

[0002] As a mature hydrogen production technology at this stage, water electrolysis in alkaline electrolyzers is widely used in wind power generation hydrogen production technology and photovoltaic power generation hydrogen production technology. However, due to the strong regional fluctuations, day and night intermittent and temperature fluctuations in the application of wind power generation hydrogen production technology and photovoltaic power generation technology, the hydrogen production system needs to have the functions of rapid heating and cooling to adapt to the temperature fluctuations caused by the ambient temperature. Summary of the invention

[0003] The present application provides an alkaline water electrolysis hydrogen production system and a control method thereof to address deficiencies in the related art.

[0004] According to a first aspect of an embodiment of the present application, there is provided an alkaline water electrolysis hydrogen production system, comprising:

[0005] Gas-liquid separation components;

[0006] an alkaline electrolytic cell, wherein the outlet of the alkaline electrolytic cell is in communication with the inlet of the gas-liquid separation component;

[0007] A hot alkali liquid tank, the hot alkali liquid tank being in communication with the first outlet of the gas-liquid separation component;

[0008] Cold caustic soda tank;

[0009] a first circulation pump, the first circulation pump being connected between the gas-liquid separation component and the hot alkali liquid tank;

[0010] a first three-way valve connected to an outlet of the hot alkali solution tank, an outlet of the cold alkali solution tank, and a first inlet of the alkaline electrolytic cell;

[0011] a second circulation pump, the second circulation pump being connected between the first three-way valve and the alkaline electrolytic cell;

[0012] A controller is used to control the first three-way valve to switch to a first working state or a second working state. When the first three-way valve is in the first working state, the outlet of the hot alkali solution tank is connected to the first inlet of the alkaline electrolytic cell. When the first three-way valve is in the second working state, the outlet of the cold alkali solution tank is connected to the first inlet of the alkaline electrolytic cell.

[0013] Optionally, also include:

[0014] a first solenoid valve, the first solenoid valve being arranged between the hot alkali liquid tank and the first three-way valve to open or close a passage between the first three-way valve and the hot alkali liquid tank;

[0015] a second solenoid valve, the second solenoid valve being arranged between the cold alkali liquid tank and the first three-way valve to open or close a passage between the first three-way valve and the cold alkali liquid tank;

[0016] When the first three-way valve is switched to the first working state, the controller controls the second solenoid valve to close and the first solenoid valve to open. When the first three-way valve is switched to the second working state, the controller controls the first solenoid valve to close and the second solenoid valve to open.

[0017] Optionally, also include:

[0018] A temperature sensor, the temperature sensor is used to detect the temperature of the alkali solution flowing out of the alkaline electrolytic cell;

[0019] The controller is in communication connection with the temperature sensor, and is used for controlling the switching of the working state of the first three-way valve according to the temperature of the alkali solution.

[0020] Optionally, also include:

[0021] a third solenoid valve, the third solenoid valve being disposed between the first outlet of the gas-liquid separation component and the hot alkali liquid tank, for opening or closing a passage between the gas-liquid separation component and the hot alkali liquid tank;

[0022] a fourth solenoid valve, the fourth solenoid valve being disposed between the second outlet of the gas-liquid separation component and the second inlet of the alkaline electrolytic cell, for opening or closing a passage between the gas-liquid separation component and the alkaline electrolytic cell;

[0023] a third circulation pump, the third circulation pump being arranged between the second outlet of the gas-liquid separation assembly and the second inlet of the alkaline electrolytic cell;

[0024] Cold water tank;

[0025] a second three-way valve, the second three-way valve connecting the second outlet of the gas-liquid separation component, the second inlet of the alkaline electrolytic cell and the cold water tank;

[0026] The controller is used to control the third solenoid valve to open and one of the fourth solenoid valves to close, and to control the other to open. When the third solenoid valve is opened, the controller is also used to control the working state switching of the first three-way valve. When the fourth solenoid valve is opened, the controller is also used to control the working state of the second three-way valve to open or close the passage between the cold water tank and the alkaline electrolytic cell.

[0027] Optionally, also include:

[0028] A fifth solenoid valve is provided between the cold water tank and the second three-way valve to open or close the passage between the cold water tank and the second three-way valve.

[0029] Optionally, also include:

[0030] A first heat exchanger is provided on a passage between the second three-way valve and the gas-liquid separation component.

[0031] Optionally, also include:

[0032] A second heat exchanger is provided on a passage between the first three-way valve and the alkaline electrolytic cell.

[0033] According to a second aspect of an embodiment of the present disclosure, a control method for an alkaline water electrolysis hydrogen production system is provided, which is applied to the alkaline water electrolysis hydrogen production system as described in any of the above embodiments, and the control method includes:

[0034] Obtaining the temperature of the alkali solution flowing out of the alkaline electrolytic cell;

[0035] When the alkaline electrolytic cell is in working state and the alkali solution temperature is greater than or equal to a preset threshold, the first three-way valve is controlled to switch to the second working state; when the alkali solution temperature is less than the preset threshold, the first three-way valve is controlled to switch to the first working state.

[0036] Optionally, applied to the hydrogen production system set forth above, the control method further comprises:

[0037] When the alkali solution temperature is greater than or equal to the preset threshold, the first three-way valve is controlled to switch to the second working state, the first solenoid valve is closed, and the second solenoid valve is opened;

[0038] When the alkali solution temperature is lower than the preset threshold, the first three-way valve is controlled to switch to a first working state, the first solenoid valve is opened, and the second solenoid valve is closed.

[0039] Optionally, in the aforementioned hydrogen production system, the working state of the alkaline electrolyzer includes a cold start state, an even load state, a loaded state, a reduced load state and a zero load state;

[0040] When the alkaline electrolytic cell is in a working state and the alkali solution temperature is greater than or equal to a preset threshold, controlling the first three-way valve to switch to the second working state, and when the alkali solution temperature is less than the preset threshold, controlling the first three-way valve to switch to the first working state also includes:

[0041] When the alkaline electrolytic cell is in a cold start state, the third solenoid valve is controlled to be opened, the fourth solenoid valve is controlled to be closed, and the first three-way valve is switched to a first working state;

[0042] When the alkaline electrolytic cell is in a loaded state or a balanced loaded state, and the alkali solution temperature is greater than or equal to the preset threshold, the third solenoid valve is controlled to be closed and the fourth solenoid valve is controlled to be opened, and the working state of the second three-way valve is to conduct the cold water tank, the alkaline electrolytic cell and the gas-liquid separation component;

[0043] When the alkaline electrolytic cell is in a load reduction state or a zero load state and the alkali solution temperature is greater than or equal to the preset threshold, the third solenoid valve is controlled to open and the fourth solenoid valve is controlled to close, and the first three-way valve is switched to the second working state.

[0044] The technical solution provided by the embodiments of the present application may have the following beneficial effects:

[0045] It can be seen from the above embodiments that in the technical solution of the present application, by switching the first three-way valve, only one of the hot alkali liquid tank or the cold alkali liquid tank is connected to the alkaline electrolytic cell, thereby realizing a decoupling configuration between the hot alkali liquid tank and the cold alkali liquid tank. When the alkaline electrolytic cell exceeds the operating temperature limit, the heat of the alkali liquid can be recovered by the hot alkali liquid tank, and the alkaline electrolytic cell can be cooled by the cold alkali liquid tank. When the alkaline electrolytic cell needs to be heated, the heat of the alkali liquid recovered from the hot alkali liquid tank can be used to heat the cell, thereby realizing the recovery and reuse of the heat of the alkali liquid.

[0046] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0048] Figure 1 It is a structural block diagram of an alkaline water electrolysis hydrogen production system according to an exemplary embodiment.

[0049] Figure 2 It is a structural block diagram of another alkaline water electrolysis hydrogen production system according to an exemplary embodiment.

[0050] Figure 3 It is a structural block diagram of another alkaline water electrolysis hydrogen production system according to an exemplary embodiment.

[0051] Figure 4The present invention is a flow chart of a control method of an alkaline water electrolysis hydrogen production system according to an exemplary embodiment.

[0052] Figure 5 It is a flow chart of another control method of an alkaline water electrolysis hydrogen production system according to an exemplary embodiment. DETAILED DESCRIPTION

[0053] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0054] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0055] It should be understood that although the terms first, second, third, etc. may be used in the present application to describe various information, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0056] Figure 1 is a structural block diagram of an alkaline water electrolysis hydrogen production system according to an exemplary embodiment. Figure 1As shown, the alkaline water electrolysis hydrogen production system may include a gas-liquid separation component 1, an alkaline electrolyzer 2, a hot alkali liquid tank 3, a cold alkali liquid tank 4, a first circulation pump 5, a second circulation pump 6 and a first three-way valve 7. Among them, the outlet of the alkaline electrolyzer 2 is connected to the inlet of the gas-liquid separation component 1, and the alkali liquid and hydrogen can be separated through the gas-liquid separation component 1, and the hydrogen can be further transmitted to the hydrogen storage tank for storage or transmitted to other hydrogen systems for use. The hot alkali liquid tank 3 can be connected to the first outlet 111 of the gas-liquid separation component 1, and the alkali liquid separated from the gas-liquid separation component 1 can be recovered through the hot alkali liquid tank 3, and since heat is generated during the working process of the alkaline electrolyzer 2, the alkali liquid recovered by the hot alkali liquid tank 3 will also have a higher temperature, and the recovered heat can be stored through the hot alkali liquid tank 3.

[0057] In order to pump the alkali solution in the loop, the first circulation pump 5 is connected between the gas-liquid separation component 1 and the hot alkali solution tank 3 to pump the alkali solution flowing out of the outlet of the hot alkali solution tank 3 to speed up the circulation efficiency; the second circulation pump 6 is connected between the first three-way valve 7 and the alkaline electrolytic cell 2, and the hot alkali solution from the hot alkali solution tank 3 or the cold alkali solution from the cold alkali solution tank 4 is pumped through the second circulation pump 6 to speed up the circulation efficiency. The first three-way valve 7 connects the outlet of the hot alkali solution tank 3, the outlet of the cold alkali solution tank 4 and the first inlet 21 of the alkaline electrolytic cell 2, and the working state of the first three-way valve 7 can be controlled later, so that one of the hot alkali solution tank 3 and the cold alkali solution tank 4 is connected to the alkaline electrolytic cell 2.

[0058] For example, the alkaline water electrolysis hydrogen production system also includes a controller, which is communicated with the first three-way valve 7, and the first three-way valve 7 is controlled by the controller to switch between a first working state and a second working state, wherein when the first three-way valve 7 is in the first working state, the outlet 3 of the hot alkali liquid tank is connected to the first inlet 21 of the alkaline electrolytic cell 2, and when the first three-way valve 7 is in the second working state, the outlet of the cold alkali liquid tank 4 is connected to the first inlet 21 of the alkaline electrolytic cell 2. For example, the controller can switch the working state of the first three-way valve 7 according to the working state of the alkaline electrolytic cell 2. For example, when the alkaline electrolytic cell 2 is in a normal operating state, the first three-way valve 7 can be controlled to switch to the second working state. At this time, the alkali solution separated from the gas-liquid separation component 1 can be recovered and stored in the hot alkali solution tank 3, and cold alkali solution with a lower temperature is introduced into the alkaline electrolytic cell 2 through the path of cold alkali solution tank 4-first three-way valve 7-alkaline electrolytic cell 2 to cool the alkaline electrolytic cell 2; for another example, when the alkaline electrolytic cell 2 is in a cold start state, or the real-time temperature in the alkaline electrolytic cell 2 is lower than the working temperature requirement, the first three-way valve 7 can be controlled to switch to the first working state, and the alkali solution with a higher temperature stored in the hot alkali solution tank 3 is directly introduced into the alkaline electrolytic cell 2, so as to realize the reuse of the heat of the alkali solution, accelerate the heating rate of the alkaline electrolytic cell 2, and improve the hydrogen production performance.

[0059] Of course, in some other embodiments, the first three-way valve 7 can be controlled to switch between the first working state and the second working state according to the temperature of the alkali solution flowing out of the alkaline electrolytic cell 2. For example, when the temperature of the alkali solution is equal to or higher than the preset threshold value, it means that the working temperature in the alkaline electrolytic cell 2 is too high, so the first three-way valve 7 can be controlled to switch to the second working state, and the alkali solution with a higher temperature is recovered through the passage of the alkaline electrolytic cell 2-gas-liquid separation component 1-hot alkali solution tank 3, and the cold alkali solution is introduced into the alkaline electrolytic cell 2 through the passage of the cold alkali solution tank 4-first three-way valve 7-alkaline electrolytic cell 2 to cool down and improve the cooling effect; when the temperature of the alkali solution is less than the preset threshold value, the first three-way valve 7 can be controlled to switch to the first working state, and the alkali solution is recovered and reused through the loop of the alkaline electrolytic cell 2-gas-liquid separation component 1-hot alkali solution tank 3-first three-way valve 7-alkaline electrolytic cell 2, and the working temperature of the alkaline electrolytic cell 2 can be maintained within a relatively stable range.

[0060] In some embodiments, Figure 1 As shown, the alkaline water electrolysis hydrogen production system may also include a temperature sensor 9, which can be used to detect the temperature of the alkali solution flowing out of the alkaline electrolytic cell 2. The temperature sensor 9 is connected to the controller in communication, and the controller can obtain the alkali solution temperature detected by the temperature sensor 9, and control the working state switching of the first three-way valve 7 according to the alkali solution temperature. For example, when the alkali solution temperature is greater than or equal to a preset threshold, the cold alkali solution tank 4 is controlled to be connected to the alkaline electrolytic cell 2, and when the alkali solution temperature is less than a preset threshold, the hot alkali solution tank 3 is controlled to be connected to the alkaline electrolytic cell 2. Among them, the temperature sensor 9 can be arranged at the outlet position of the alkaline electrolytic cell 2, or it can also be arranged on the passage pipe between the gas-liquid separation component 1 and the alkaline electrolytic cell 2, and this application does not limit this.

[0061] It can be seen from the above embodiments that in the technical solution of the present application, by switching the first three-way valve 7, only one of the hot alkali liquid tank 3 and the cold alkali liquid tank 4 is connected to the alkaline electrolytic cell 2, which is beneficial for recovering and storing the alkali liquid heat through the hot alkali liquid tank 3 and cooling the alkaline electrolytic cell 2 through the cold alkali liquid tank 4 when the alkaline electrolytic cell 2 exceeds the operating temperature limit. When the alkaline electrolytic cell 2 needs to be heated, the alkali liquid heat recovered from the hot alkali liquid tank 3 can be used to realize the recovery and reuse of the alkali liquid heat.

[0062] In the above embodiments, only one of the cold alkali solution tank 4 and the hot alkali solution tank 3 is connected to the alkaline electrolytic cell 2. Figure 2As shown, the alkaline water electrolysis hydrogen production system can also include a first solenoid valve 10 and a second solenoid valve 11. The first solenoid valve 10 is arranged between the hot alkali liquid tank 3 and the first three-way valve 7 to open or close the passage between the first three-way valve 7 and the hot alkali liquid tank 3; the second solenoid valve 11 is arranged between the cold alkali liquid tank 4 and the first three-way valve 7 to open or close the passage between the first three-way valve 7 and the cold alkali liquid tank 4.

[0063] The controller can be communicatively connected with the first solenoid valve 10 and the second solenoid valve 11 respectively. When the controller controls the first three-way valve 7 to switch to the first working state, the controller can also control the first solenoid valve 10 to open and the second solenoid valve 11 to close, thereby ensuring the disconnection between the cold alkali liquid tank 4 and the alkaline electrolytic tank 2 through the double closure of the second solenoid valve 11 and the first three-way valve 7, thereby realizing "double insurance" protection; similarly, when the controller controls the first three-way valve 7 to switch to the second working state, the controller can also control the first solenoid valve 10 to close and the second solenoid valve 11 to open, thereby ensuring the disconnection between the hot alkali liquid tank 3 and the alkaline electrolytic tank 2 through the double closure of the first solenoid valve 10 and the first three-way valve 7, thereby realizing "double insurance" protection.

[0064] Based on the above embodiments, Figure 3 As shown, the alkaline water electrolysis hydrogen production system may also include a third solenoid valve 13, a fourth solenoid valve 14, a third circulation pump 15, a cold water tank 16 and a second three-way valve 17. Among them, the third solenoid valve 13 is arranged between the first outlet 111 of the gas-liquid separation component 1 and the hot alkali liquid tank 3, so as to open or close the passage between the gas-liquid separation component 1 and the hot alkali liquid tank 3. The fourth solenoid valve 14 is arranged between the second outlet 112 of the gas-liquid separation component 1 and the second inlet 22 of the alkaline electrolyzer 2, so as to open or close the passage between the gas-liquid separation component 11 and the alkaline electrolyzer 2. The third circulation pump 15 is arranged between the second outlet 112 of the gas-liquid separation component 1 and the second inlet 22 of the alkaline electrolyzer 2, so as to pump the alkali liquid separated from the gas-liquid separation component 1 to the second inlet 2222 of the alkaline electrolyzer 2, and reflux into the alkaline electrolyzer 2.

[0065] The second three-way valve 17 is connected to the second outlet 112 of the gas-liquid separation component 1, the second inlet 22 of the alkaline electrolytic cell 2 and the cold water tank 16. The controller is communicated with the second three-way valve 17, the third solenoid valve 13 and the fourth solenoid valve 14 respectively. The controller can be used to control one of the third solenoid valve 13 and the fourth solenoid valve 14 to be closed and the other to be opened. When the third solenoid valve 13 is opened, the controller is also used to control the working state switching of the first three-way valve 7. When the fourth solenoid valve 14 is opened, the controller is also used to control the working state of the second three-way valve 17 to open or close the passage between the cold water tank 16 and the alkaline electrolytic cell 2, thereby determining whether to add cold water to the alkaline solution refluxed from the second outlet 112 of the gas-liquid separation component 1 to the alkaline electrolytic cell 2, which is beneficial to the subsequent cooling of the alkaline electrolytic cell 2 when the temperature is too high.

[0066] For example, when the third solenoid valve 13 is closed and the fourth solenoid valve 14 is opened, the working state of the second three-way valve 17 can be controlled to switch to control whether cold water is introduced into the alkaline electrolytic cell 2 for cooling. For example, when the temperature of the alkali solution is greater than or equal to the preset threshold, the second three-way valve 17 can be controlled to conduct the cold water tank 16 and the alkaline electrolytic cell 2, and on the basis of the circuit of the alkaline electrolytic cell 2-gas-liquid separation component 1-fourth solenoid valve 14-third circulation pump 15-second three-way valve 17-alkaline electrolytic cell 2, the circuit of the cold water tank 16-alkaline electrolytic cell 2 is added, and cold water is added to the refluxed alkali solution to cool the alkaline electrolytic cell 2. For another example, when the temperature of the alkali solution is less than the preset threshold, the circuit of the alkaline electrolytic cell 2-gas-liquid separation component 1-fourth solenoid valve 14-third circulation pump 15-second three-way valve 17-alkaline electrolytic cell 2 is used to realize the reflux of the alkali solution.

[0067] Among them, since water can be used as the electrolysis object of the alkaline electrolytic cell 2, when the alkaline electrolytic cell 2 is in a conventional evenly loaded state or a loaded state, that is, when the alkaline electrolytic cell 2 is in a high current density, the third solenoid valve 13 can be controlled by the controller to close and the fourth solenoid valve 14 can be controlled to open, and the second three-way valve 17 can be controlled to conduct the cold water tank 16 and the alkaline electrolytic cell 2 to achieve cooling; and when the alkaline electrolytic cell 2 is in a reduced load state or a zero load state, since the amount of water that can be electrolyzed by the alkaline electrolytic cell 2 decreases, in order not to introduce additional water, the third solenoid valve 13 can be controlled by the controller to open and the fourth solenoid valve 14 can be controlled to close, and the first three-way valve 7 can be controlled to switch between the first working state and the second working state according to demand. The specific alkali solution passage can refer to the aforementioned embodiment.

[0068] Based on this design, according to the load state of the alkaline electrolytic cell 2, the first outlet 111 of the gas-liquid separation component 1 can be switched to be connected with the first inlet 21 of the alkaline electrolytic cell 2, or the second outlet 112 of the gas-liquid separation component 1 can be switched to be connected with the second inlet 22 of the alkaline electrolytic cell 2, so as to achieve rapid cooling while avoiding the addition of additional water in the load reduction state or the zero load state.

[0069] In some embodiments, the alkaline water electrolysis hydrogen production system may further include a fifth solenoid valve 18, which is disposed between the cold water tank 16 and the second three-way valve 17, and is used to open or close the passage between the cold water tank 16 and the second three-way valve 17. For example, when the controller controls the second three-way valve 17 to close the passage between the cold water tank 16 and the alkaline electrolyzer 2, the fifth solenoid valve 18 may be controlled to be disconnected to ensure that the passage between the cold water tank 16 and the alkaline electrolyzer 2 is disconnected; when the controller controls the second three-way valve 17 to close the conduction between the cold water tank 16 and the alkaline electrolyzer 2, the fifth solenoid valve 18 may be controlled to be connected to ensure that the passage between the cold water tank 16 and the alkaline electrolyzer 2 is connected.

[0070] In some embodiments, the alkaline water electrolysis hydrogen production system may further include a first heat exchanger 19, which may be disposed in the passage between the second three-way valve 17 and the gas-liquid separation component 1, and heat exchange is performed between the first heat exchanger 19 and the liquid in the pipeline between the second three-way valve 17 and the gas-liquid separation component 1 to achieve further heating or cooling.

[0071] In some embodiments, the alkaline water electrolysis hydrogen production system may further include a second heat exchanger 20, which is disposed on the passage between the first three-way valve 7 and the alkaline electrolyzer 2. The second heat exchanger 20 performs heat exchange with the liquid in the pipeline between the first three-way valve 7 and the alkaline electrolyzer 2 to achieve further heating or cooling.

[0072] Based on the technical solution of the present disclosure, a control method for an alkaline water electrolysis hydrogen production system is also provided, and the control method can be applied to the alkaline water electrolysis hydrogen production system described in any of the above embodiments. Figure 4 As shown, the control method may further include the following steps:

[0073] In step 401, the temperature of the alkaline solution flowing out of the alkaline electrolytic cell 2 is obtained.

[0074] In some embodiments, a temperature sensor can be arranged on the pipeline between the alkaline electrolytic cell 2 and the gas-liquid separation component 1, and the temperature of the alkali liquid flowing out of the alkaline electrolytic cell 2 is detected by the temperature sensor 9; or in other embodiments, a temperature sensor can be integrated in the alkaline electrolytic cell 2 to detect the temperature of the alkali liquid. The specific design can be as needed, and the present disclosure does not limit this.

[0075] In step 402, when the alkaline electrolytic cell is in working state and the alkali solution temperature is greater than or equal to a preset threshold, the first three-way valve is controlled to switch to the second working state; when the alkali solution temperature is less than the preset threshold, the first three-way valve is controlled to switch to the first working state.

[0076] In some embodiments, when the alkali solution temperature is greater than or equal to a preset threshold value, it indicates that the temperature in the alkaline electrolytic cell 2 has exceeded the limit temperature at this time, so the cold alkali solution tank 4 and the alkaline electrolytic cell 2 can be connected through the first three-way valve 7, and the cold alkali solution tank 4-first three-way valve 7-alkaline electrolytic cell 2 is used to directly introduce cold alkali solution into the alkaline electrolytic cell 2 for cooling; and through the alkaline electrolytic cell 2-gas-liquid separation component 1-hot alkali solution tank 3, the alkali solution separated from the gas-liquid separation component 1 can flow into the hot alkali solution tank 3 with a heat preservation function for recovery and storage. When the alkali solution temperature is less than the preset threshold value, it indicates that the temperature of the alkaline electrolytic cell 2 is within the operating temperature range at this time, and there is no need to cool down or heat up, so the hot alkali solution tank 3 and the alkaline electrolytic cell 2 can be connected through the first three-way valve 7, and the conventional alkali solution circulation is performed through the loop of the alkaline electrolytic cell 2-gas-liquid separation component 1-hot alkali solution tank 3-first three-way valve 7-alkaline electrolytic cell 2. Moreover, since heat is stored in the hot alkali solution tank 3, when the alkali solution temperature is lower than the lowest temperature in the working temperature range, the hot alkali solution tank 3 and the alkaline electrolytic tank 2 can be connected through the first three-way valve 7 to increase the temperature of the alkaline electrolytic tank 2.

[0077] Based on this, by arranging the hot alkali liquid tank 3 and the cold alkali liquid tank 4 respectively, the decoupling between the cold alkali liquid and the hot alkali liquid is achieved. Subsequently, the first three-way valve 7 can be controlled to switch the working state according to demand to achieve the passage switching between the first outlet 111 of the gas-liquid separation component 1 and the first inlet 21 of the alkaline electrolytic cell 2.

[0078] Furthermore, the control method may also include, when the alkali solution temperature is greater than or equal to the preset threshold, controlling the first three-way valve 7 to switch to the second working state, closing the first solenoid valve 10, and opening the second solenoid valve 11, thereby ensuring the disconnection between the hot alkali solution tank 3 and the alkaline electrolytic cell 2 through the double closure of the first solenoid valve 10 and the first three-way valve 7, thereby achieving "double insurance" protection; when the alkali solution temperature is less than the preset threshold, when the first three-way valve 7 is controlled to switch to the first working state, the first solenoid valve 10 may be controlled to close and the second solenoid valve 11 may be controlled to open, thereby ensuring the disconnection between the cold alkali solution tank 4 and the alkaline electrolytic cell 2 through the double closure of the second solenoid valve 11 and the first three-way valve 7, thereby achieving "double insurance" protection.

[0079] like Figure 5 As shown, the control method of the alkaline water electrolysis hydrogen production system may include the following steps:

[0080] In step 501, the working state of the alkaline electrolytic cell is obtained.

[0081] In this embodiment, the working state of the alkaline electrolytic cell 2 may include a cold start state, an evenly loaded state, a loaded state, a reduced load state and a zero load state, wherein the evenly loaded state may be understood as a state in which the current density of the alkaline electrolytic cell 2 remains substantially unchanged, the loaded state may be understood as a process in which the current density of the alkaline electrolytic cell 2 increases, the reduced load state may be understood as a process in which the current density of the alkaline electrolytic cell 2 decreases, and the zero load state is a shutdown state of the alkaline electrolytic cell 2.

[0082] In step 502, when the alkaline electrolytic cell is in a cold start state, the third solenoid valve 13 is controlled to be opened, the fourth solenoid valve 14 is controlled to be closed, and the first three-way valve 7 is switched to the first working state.

[0083] In this embodiment, the cold start state means that the starting temperature of the alkaline electrolytic cell is much lower than the working temperature of the alkaline electrolytic cell 2. Therefore, a loop of alkaline electrolytic cell 2-gas-liquid separation component 1-third solenoid valve 13-hot alkali liquid tank 3-second circulation pump 6-alkaline electrolytic cell 2 can be used to quickly heat up the alkaline electrolytic cell.

[0084] In step 503, when the alkaline electrolytic cell 2 is in a loaded state or a balanced load state, it is determined whether the alkaline solution temperature is greater than or equal to a preset threshold.

[0085] In step 504 , when the alkali solution temperature is greater than or equal to a preset threshold, the third solenoid valve 13 is controlled to be closed and the fourth solenoid valve 14 is controlled to be opened, and the working state of the second three-way valve 17 is connected to the cold water tank 16 , the alkaline electrolytic cell 2 and the gas-liquid separation component 1 .

[0086] In step 505 , when the alkali solution temperature is less than a preset threshold, the third solenoid valve 13 is controlled to be closed, the fourth solenoid valve 14 is controlled to be opened, and the working state of the second three-way valve 17 disconnects the cold water tank 16 and the alkaline electrolytic cell 2 .

[0087] In this embodiment, when the alkali solution temperature is less than a preset threshold value, it means that the temperature of the alkaline electrolytic cell 2 is normal in a loaded state or a uniformly loaded state. Therefore, a circuit of an alkaline electrolytic cell 2-gas-liquid separation component 1-fourth solenoid valve 14-third circulation pump 9-second three-way valve 17-alkaline electrolytic cell 2 can be used to realize the reuse of the alkali solution; when the alkali solution temperature is greater than or equal to the preset threshold value, a circuit of a cold water tank 16-fifth solenoid valve 18-second three-way valve 17-alkaline electrolytic cell 2 can be added on the basis of the circuit of the alkaline electrolytic cell 2-gas-liquid separation component 1-fourth solenoid valve 14-third circulation pump 9-second three-way valve 17-alkaline electrolytic cell 2, and cold water is added to the refluxed alkali solution to cool the alkaline electrolytic cell 2.

[0088] In step 506, when the alkaline electrolytic cell 2 is in a load reduction state or a zero load state, it is determined whether the alkaline solution temperature is greater than or equal to a preset threshold.

[0089] In step 507, when the alkali solution temperature is greater than or equal to a preset threshold, the third solenoid valve 13 is controlled to open and the fourth solenoid valve 14 is controlled to close, and the first three-way valve 7 is switched to the second working state, so that the cold alkali solution tank 4 is connected to the alkaline electrolytic tank 2, and the hot alkali solution tank 3 is disconnected from the alkaline electrolytic tank 2.

[0090] In step 508, when the alkali solution temperature is less than a preset threshold, the third solenoid valve 13 is controlled to open and the fourth solenoid valve 14 is controlled to close, and the first three-way valve 7 is switched to the first working state, so that the cold alkali solution tank 4 is disconnected from the alkaline electrolytic tank 2, and the hot alkali solution tank 3 is connected to the alkaline electrolytic tank 2.

[0091] In this embodiment, when the alkali solution temperature is less than the preset threshold value, it means that the temperature of the alkaline electrolytic cell 2 is normal in the load-reducing state or the zero-load state, so the loop of the alkaline electrolytic cell 2-gas-liquid separation component 1-third solenoid valve 13-hot alkali solution tank 3-second circulation pump 6-alkaline electrolytic cell 2 can be used to realize the reuse of the alkali solution, and since the working power of the alkaline electrolytic cell 2 is reduced, the use of this loop will not introduce additional water. When the alkali solution temperature is greater than or equal to the preset threshold value, it means that the temperature of the alkaline electrolytic cell 2 exceeds the limit temperature in the load-reducing state or the zero-load state, and the loop of the alkaline electrolytic cell 2-gas-liquid separation component 1-third solenoid valve 13-hot alkali solution tank 3 can be used to recover the alkali solution and the heat in the alkali solution, and at the same time, the loop of the cold alkali solution tank 4-second solenoid valve 11-first three-way valve 7-second circulation pump 6-alkaline electrolytic cell 2 is used to add cold alkali solution to the alkaline electrolytic cell 2 to realize the rapid cooling of the alkaline electrolytic cell 2. The flow rate of the alkali solution passage can be controlled so that the amount of alkali solution added from the cold alkali solution tank 4 to the alkaline electrolytic tank 2 is equal to the amount of alkali solution flowing from the gas-liquid separation component 1 into the hot alkali solution tank 3 .

[0092] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the disclosure disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0093] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. An alkaline water electrolysis hydrogen production system, characterized in that: include: Gas-liquid separation components; an alkaline electrolytic cell, wherein the outlet of the alkaline electrolytic cell is in communication with the inlet of the gas-liquid separation component; A hot alkali liquid tank, the hot alkali liquid tank being in communication with the first outlet of the gas-liquid separation component; Cold caustic soda tank; a first circulation pump, the first circulation pump being connected between the gas-liquid separation component and the hot alkali liquid tank; a first three-way valve connected to an outlet of the hot alkali solution tank, an outlet of the cold alkali solution tank, and a first inlet of the alkaline electrolytic cell; a second circulation pump, the second circulation pump being connected between the first three-way valve and the alkaline electrolytic cell; A controller is used to control the first three-way valve to switch to a first working state or a second working state. When the first three-way valve is in the first working state, the outlet of the hot alkali solution tank is connected to the first inlet of the alkaline electrolytic cell. When the first three-way valve is in the second working state, the outlet of the cold alkali solution tank is connected to the first inlet of the alkaline electrolytic cell.

2. The alkaline water electrolysis hydrogen production system according to claim 1, characterized in that: Also includes: a first solenoid valve, the first solenoid valve being arranged between the hot alkali liquid tank and the first three-way valve to open or close a passage between the first three-way valve and the hot alkali liquid tank; a second solenoid valve, the second solenoid valve being arranged between the cold alkali liquid tank and the first three-way valve to open or close a passage between the first three-way valve and the cold alkali liquid tank; When the first three-way valve is switched to the first working state, the controller controls the second solenoid valve to close and the first solenoid valve to open. When the first three-way valve is switched to the second working state, the controller controls the first solenoid valve to close and the second solenoid valve to open.

3. The alkaline water electrolysis hydrogen production system according to claim 1, characterized in that: Also includes: A temperature sensor, the temperature sensor is used to detect the temperature of the alkali solution flowing out of the alkaline electrolytic cell; The controller is in communication connection with the temperature sensor, and is used for controlling the switching of the working state of the first three-way valve according to the temperature of the alkali solution.

4. The alkaline water electrolysis hydrogen production system according to claim 1, characterized in that: Also includes: a third solenoid valve, the third solenoid valve being disposed between the first outlet of the gas-liquid separation component and the hot alkali liquid tank, for opening or closing a passage between the gas-liquid separation component and the hot alkali liquid tank; a fourth solenoid valve, the fourth solenoid valve being disposed between the second outlet of the gas-liquid separation component and the second inlet of the alkaline electrolytic cell, for opening or closing a passage between the gas-liquid separation component and the alkaline electrolytic cell; a third circulation pump, the third circulation pump being arranged between the second outlet of the gas-liquid separation assembly and the second inlet of the alkaline electrolytic cell; Cold water tank; a second three-way valve, the second three-way valve connecting the second outlet of the gas-liquid separation component, the second inlet of the alkaline electrolytic cell and the cold water tank; The controller is used to control the third solenoid valve to open and one of the fourth solenoid valves to close, and to control the other to open. When the third solenoid valve is opened, the controller is also used to control the working state switching of the first three-way valve. When the fourth solenoid valve is opened, the controller is also used to control the working state of the second three-way valve to open or close the passage between the cold water tank and the alkaline electrolytic cell.

5. The alkaline water electrolysis hydrogen production system according to claim 4, characterized in that: Also includes: A fifth solenoid valve is provided between the cold water tank and the second three-way valve to open or close the passage between the cold water tank and the second three-way valve.

6. The alkaline water electrolysis hydrogen production system according to claim 4, characterized in that: Also includes: A first heat exchanger is provided on a passage between the second three-way valve and the gas-liquid separation component.

7. The alkaline water electrolysis hydrogen production system according to claim 1, characterized in that: Also includes: A second heat exchanger is provided on a passage between the first three-way valve and the alkaline electrolytic cell.

8. A control method for an alkaline water electrolysis hydrogen production system, characterized in that: Applied to the alkaline water electrolysis hydrogen production system according to any one of claims 1 to 7, the control method comprises: Obtaining the temperature of the alkali solution flowing out of the alkaline electrolytic cell; When the alkaline electrolytic cell is in working state and the alkali solution temperature is greater than or equal to a preset threshold, the first three-way valve is controlled to switch to the second working state; when the alkali solution temperature is less than the preset threshold, the first three-way valve is controlled to switch to the first working state.

9. The control method according to claim 8, characterized in that: Applied to the hydrogen production system according to claim 2, the control method further comprises: When the alkali solution temperature is greater than or equal to the preset threshold, the first three-way valve is controlled to switch to the second working state, the first solenoid valve is closed, and the second solenoid valve is opened; When the alkali solution temperature is lower than the preset threshold, the first three-way valve is controlled to switch to a first working state, the first solenoid valve is opened, and the second solenoid valve is closed.

10. The control method according to claim 8, characterized in that: Applied to the hydrogen production system of claim 4, the working state of the alkaline electrolyzer includes a cold start state, an even load state, a loaded state, a reduced load state and a zero load state; When the alkaline electrolytic cell is in a working state and the alkali solution temperature is greater than or equal to a preset threshold, controlling the first three-way valve to switch to the second working state, and when the alkali solution temperature is less than the preset threshold, controlling the first three-way valve to switch to the first working state also includes: When the alkaline electrolytic cell is in a cold start state, the third solenoid valve is controlled to be opened, the fourth solenoid valve is controlled to be closed, and the first three-way valve is switched to a first working state; When the alkaline electrolytic cell is in a loaded state or a balanced loaded state, and the alkali solution temperature is greater than or equal to the preset threshold, the third solenoid valve is controlled to be closed and the fourth solenoid valve is controlled to be opened, and the working state of the second three-way valve is to conduct the cold water tank, the alkaline electrolytic cell and the gas-liquid separation component; When the alkaline electrolytic cell is in a load reduction state or a zero load state and the alkali solution temperature is greater than or equal to the preset threshold, the third solenoid valve is controlled to open and the fourth solenoid valve is controlled to close, and the first three-way valve is switched to the second working state.

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