Seawater hydrogen production device and control method based on variable migration area alkali solution regeneration pump

Abstract

The present invention discloses a seawater hydrogen production device based on a variable migration area alkali solution regeneration pump and a control method. The device includes an alkali solution hydrogen production electrolyzer, a peristaltic pump, a variable migration area alkali solution regeneration pump, a seawater microenvironment tank and a concentration detection instrument. The alkali solution hydrogen production electrolyzer and the variable migration area alkali solution regeneration pump are connected through the peristaltic pump. The variable migration area alkali solution regeneration pump is arranged in the seawater microenvironment tank. By controlling the effective exchange area between the variable migration area alkali solution regeneration pump and seawater, the rate at which gaseous water migrates into the variable migration area alkali solution regeneration pump is adjusted, and the water consumption of electrolytic hydrogen production and the water migration in the variable migration area alkali solution regeneration pump are controlled to achieve dynamic balance, thereby achieving a constant concentration in the variable migration area alkali solution regeneration pump, and finally maintaining the alkali solution concentration in the alkali solution hydrogen production electrolyzer near the optimal conductivity concentration, thereby achieving high-efficiency seawater hydrogen production. The present invention can improve the dynamic performance of seawater hydrogen production, expand the operating range, and enhance the operating stability.

Description

Technical Field

[0001] The present invention belongs to the technical field of direct hydrogen production by electrolysis of seawater in the field of new energy, and in particular relates to a seawater hydrogen production device based on a variable migration area alkali solution regeneration pump and a control method. Background Art

[0002] For a long time, water electrolysis has been considered unfeasible at the economic level. It cannot be compared with existing fossil fuel hydrogen production methods, either from the perspective of electricity consumption or water resource consumption. But compared with other methods of hydrogen production such as steam methane reforming or coal gasification, renewable energy water electrolysis is the most effective way to obtain hydrogen. It consumes water and only produces oxygen and hydrogen, so it does not produce greenhouse gases and other harmful pollutants. In addition, due to the rapid development of photovoltaics and wind turbines in recent years, water electrolysis has become increasingly promising due to its potential for integration with renewable energy. Water electrolysis can make up for the intermittent and volatile nature of renewable energy, release the pressure of renewable energy on the power system, and couple well with the power grid as a flexible resource.

[0003] Direct hydrogen production from seawater will not only greatly save freshwater resources, but also reduce the cost of hydrogen production, which is crucial to the development of hydrogen energy. As a new hydrogen production method with potential energy conversion efficiency and environmental friendliness, direct hydrogen production from seawater has received widespread attention. However, during the seawater electrolysis process, the stability of the alkali concentration inside the electrolyzer has always been a challenge. The present invention is a seawater hydrogen production device and control method based on a variable migration area alkali regeneration pump, which aims to dynamically adjust the migration rate of pure water in seawater to the alkali in the electrolyzer to maintain the constant alkali concentration in the electrolyzer (maintained at the highest efficiency concentration), thereby reducing the energy consumption of the hydrogen production process. Summary of the invention

[0004] The purpose of the present invention is to provide a seawater hydrogen production device and control method based on a variable migration area alkali solution regeneration pump in view of the shortcomings of the prior art. The present invention solves the problems of poor dynamic performance, narrow operating range and unstable operation of direct hydrogen production from seawater, so that direct hydrogen production from seawater can achieve stable and efficient operation under a wide range of power fluctuation conditions.

[0005] The objective of the present invention is achieved through the following technical solutions: In a first aspect, an embodiment of the present invention provides a seawater hydrogen production device based on a variable migration area alkali solution regeneration pump, comprising an alkali solution hydrogen production electrolyzer, a peristaltic pump, a variable migration area alkali solution regeneration pump, a seawater microenvironment tank and a concentration detection instrument; wherein the alkali solution hydrogen production electrolyzer and the variable migration area alkali solution regeneration pump are connected through a peristaltic pump, and the variable migration area alkali solution regeneration pump is arranged in the seawater microenvironment tank; by controlling the effective exchange migration area between the variable migration area alkali solution regeneration pump and the seawater in the seawater microenvironment tank, adjusting the speed at which gaseous water migrates into the variable migration area alkali solution regeneration pump, controlling the water consumption in the electrolytic hydrogen production process of the alkali solution hydrogen production electrolyzer and the water migration in the variable migration area alkali solution regeneration pump to achieve dynamic balance, so as to achieve a constant concentration in the variable migration area alkali solution regeneration pump; the alkali solution concentrations in the alkali solution hydrogen production electrolyzer and the variable migration area alkali solution regeneration pump are kept dynamically consistent through the circulation operation of the peristaltic pump; the concentration detection instrument is used to measure the potassium hydroxide concentration in the variable migration area alkali solution regeneration pump.

[0006] Furthermore, the alkali solution hydrogen production electrolytic cell relies on liquid exchange with a variable migration area alkali solution regeneration pump for circulating heat dissipation, and the pure water consumed in the hydrogen production process of the alkali solution hydrogen production electrolytic cell relies on the variable migration area alkali solution regeneration pump to replenish.

[0007] Furthermore, the peristaltic pump includes a suction pump and a replenishment pump, wherein the suction pump is used to extract alkali solution from the alkali solution hydrogen production electrolyzer, and the replenishment pump is used to replenish alkali solution into the alkali solution hydrogen production electrolyzer; the speed of replenishing alkali solution is greater than the speed of extracting alkali solution, so that the liquid level in the alkali solution hydrogen production electrolyzer maintains dynamic balance.

[0008] Furthermore, the variable migration area alkali solution regeneration pump is provided with fan blades and a variable contact area control module for controlling the opening of the fan blades. The inner surface of the variable migration area alkali solution regeneration pump is adhered with a hydrophobic porous polytetrafluoroethylene-based film. The alkali solution in the variable migration area alkali solution regeneration pump is a concentrated potassium hydroxide solution with a concentration of 30%.

[0009] Furthermore, the hydrophobic porous polytetrafluoroethylene-based membrane is used as a gaseous water exchange channel, and the hydrophobic porous polytetrafluoroethylene-based membrane is between seawater and alkali solution. The transmembrane water vapor pressure difference between seawater and concentrated potassium hydroxide solution drives the transfer of water molecules. The pressure difference on the seawater side causes the seawater to spontaneously vaporize, and the water vapor is transported to the alkali solution side through short-path diffusion in the hydrophobic porous polytetrafluoroethylene-based membrane, in which the water vapor is absorbed and reliquefied, and this phase change migration process realizes the in-situ generation of pure water for electrolysis in seawater; the ion blocking efficiency of the hydrophobic porous polytetrafluoroethylene-based membrane reaches 100%.

[0010] Furthermore, the variable contact area control module adjusts the effective exchange migration area on both sides of the hydrophobic porous polytetrafluoroethylene-based membrane by changing the fan blade opening to control the water replenishment rate of the variable migration area alkali solution regeneration pump. After receiving the concentration signal, the fan blade opening is controlled by the variable contact area control module, and its control law is expressed as:

[0011]

[0012] in, is the fan blade opening; is the PI controller, s is the Laplace operator, is the proportionality coefficient, is the integration coefficient; is the reference value of alkali solution concentration, It is the real-time alkali solution concentration.

[0013] Furthermore, the seawater microenvironment tank is provided with a valve, through which the seawater microenvironment tank and the sea are circulated to ensure that the seawater concentration in the seawater microenvironment tank is consistent with a seawater concentration reference value; the valve includes an inlet valve and a drain valve, and the speed of seawater entering and exiting the seawater microenvironment tank is controlled by changing the opening of the inlet valve and the drain valve.

[0014] Furthermore, the speed of controlling the seawater entering and exiting the seawater microenvironment tank by changing the opening of the water inlet valve and the opening of the drain valve specifically includes:

[0015] The concentration of pure water in the seawater microenvironment tank is changed by changing the opening of the water inlet valve, and the osmotic pressure difference on both sides of the hydrophobic porous polytetrafluoroethylene membrane is adjusted to control the speed at which pure water in the seawater enters the alkaline solution hydrogen production electrolyzer to achieve a constant seawater concentration in the seawater microenvironment tank. The control law is expressed as:

[0016]

[0017] in, is the water inlet valve opening; is the PI controller, s is the Laplace operator, is the proportionality coefficient, is the integration coefficient; is the reference value of seawater concentration, is the real-time seawater concentration;

[0018] The speed of seawater discharge from the seawater microenvironment tank is adjusted by changing the opening of the drain valve to control the liquid level in the seawater microenvironment tank to be constant. The control law is expressed as:

[0019]

[0020] in, is the drain valve opening; is the PI controller, s is the Laplace operator, is the proportionality coefficient, is the integration coefficient; is the reference value of the internal liquid level of the seawater microenvironment tank, It is the real-time liquid level inside the seawater microenvironment tank.

[0021] Furthermore, the concentration detection instrument measures the concentration of potassium hydroxide by adopting the refraction principle, and the range of measuring the concentration of potassium hydroxide is 20%-40%.

[0022] A second aspect of an embodiment of the present invention provides a control method for the above-mentioned seawater hydrogen production device based on a variable migration area alkali solution regeneration pump, specifically comprising:

[0023] During the electrolytic hydrogen production process of the alkali solution hydrogen production electrolyzer, the real-time alkali solution concentration in the alkali solution hydrogen production electrolyzer, the real-time seawater concentration in the seawater microenvironment tank and the real-time liquid level inside the seawater microenvironment tank are obtained in real time; the PI controller controls the opening of the water inlet valve according to the seawater concentration reference value to make the seawater concentration in the seawater microenvironment tank constant; the PI controller controls the opening of the drain valve according to the internal liquid level reference value of the seawater microenvironment tank to make the liquid level in the seawater microenvironment tank constant; the variable contact area control module controls the fan blade opening according to the alkali solution concentration reference value to adjust the effective exchange migration area on both sides of the hydrophobic porous polytetrafluoroethylene based membrane, and control the speed of gaseous water migration into the variable migration area alkali solution regeneration pump, so as to achieve a dynamic balance between the water consumption in the alkali solution hydrogen production electrolyzer and the water migration in the variable migration area alkali solution regeneration pump, and keep the alkali solution concentration in the variable migration area alkali solution regeneration pump constant; finally, the alkali solution concentration in the alkali solution hydrogen production electrolyzer maintains the optimal conductivity, and hydrogen production from seawater is achieved.

[0024] The beneficial effects of the present invention are as follows: by adding a variable migration area alkali solution regeneration pump between the alkali solution hydrogen production electrolyzer and seawater, the present invention controls the effective exchange area between the variable migration area alkali solution regeneration pump and seawater, adjusts the rate at which gaseous water migrates into the variable migration area alkali solution regeneration pump, controls the water consumption of hydrogen production by electrolysis and the water migration in the variable migration area alkali solution regeneration pump to achieve dynamic balance, thereby achieving a constant concentration in the variable migration area alkali solution regeneration pump, and ultimately maintaining the alkali solution concentration in the alkali solution hydrogen production electrolyzer near the optimal concentration for conductivity, thereby achieving efficient hydrogen production from seawater; hydrogen production from seawater using the device of the present invention is beneficial to improving the dynamic performance of hydrogen production from seawater, broadening the operating range of hydrogen production from seawater, and enhancing the operating stability of the seawater hydrogen production device, so that direct hydrogen production from seawater can achieve stable and efficient operation under a wide range of power fluctuations. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1It is a schematic diagram of the architecture of the seawater hydrogen production device based on the variable migration area alkali solution regeneration pump of the present invention;

[0026] Figure 2 The present invention is a flow chart of a control method of a seawater hydrogen production device based on a variable migration area alkali solution regeneration pump. DETAILED DESCRIPTION

[0027] 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, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0028] The terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The singular forms "a", "the" and "the" used in the present invention 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.

[0029] It should be understood that although the terms first, second, third, etc. may be used in the present invention 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 invention, 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".

[0030] The present invention is described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the features of the following embodiments and implementations can be combined with each other.

[0031] See also Figure 1The seawater hydrogen production device based on the variable migration area alkali solution regeneration pump of the present invention specifically includes an alkali solution hydrogen production electrolyzer, a peristaltic pump, a variable migration area alkali solution regeneration pump, a seawater microenvironment tank and a concentration detection instrument. Among them, the alkali solution hydrogen production electrolyzer and the variable migration area alkali solution regeneration pump are connected through the peristaltic pump, and the variable migration area alkali solution regeneration pump is arranged in the seawater microenvironment tank; by controlling the effective exchange migration area between the variable migration area alkali solution regeneration pump and the seawater in the seawater microenvironment tank, adjusting the speed of gaseous water migration into the variable migration area alkali solution regeneration pump, controlling the water consumption in the electrolytic hydrogen production process of the alkali solution hydrogen production electrolyzer and the water migration in the variable migration area alkali solution regeneration pump to achieve dynamic balance, so as to achieve constant concentration in the variable migration area alkali solution regeneration pump; the alkali solution concentration in the alkali solution hydrogen production electrolyzer and the variable migration area alkali solution regeneration pump is kept dynamically consistent through the circulation operation of the peristaltic pump; the concentration detection instrument is used to measure the potassium hydroxide concentration in the variable migration area alkali solution regeneration pump.

[0032] In this embodiment, the alkali liquid hydrogen production electrolyzer eliminates the original heat dissipation device and relies on liquid exchange with a variable migration area alkali liquid regeneration pump for circulating heat dissipation. The pure water consumed in the hydrogen production process of the alkali liquid hydrogen production electrolyzer is replenished by the variable migration area alkali liquid regeneration pump.

[0033] In this embodiment, the peristaltic pump includes two pumps, namely a suction pump and a replenishment pump. The suction pump is used to extract alkali solution from the alkali solution hydrogen production electrolyzer, and the replenishment pump is used to replenish alkali solution into the alkali solution hydrogen production electrolyzer. According to the rate at which water is consumed by electrolytic hydrogen production, the speed of replenishing alkali solution is slightly greater than the speed of extracting alkali solution, which can ensure that the liquid level in the alkali solution hydrogen production electrolyzer maintains a dynamic balance.

[0034] In this embodiment, a variable migration area alkali solution regeneration pump is provided with a fan blade and a variable contact area control module for controlling the opening of the fan blade; a hydrophobic porous polytetrafluoroethylene-based membrane is attached to the inner surface of the variable migration area alkali solution regeneration pump, and the seawater in the seawater microenvironment tank is separated from the alkali solution in the variable migration area alkali solution regeneration pump by a hydrophobic porous polytetrafluoroethylene-based membrane; using a concentrated potassium hydroxide with a concentration of 30% as the alkali solution in the variable migration area alkali solution regeneration pump, seawater in-situ water purification without additional energy consumption can be achieved. By adjusting the variable contact area control module and the fan blades to change the effective exchange migration area between the alkali solution and the seawater through the hydrophobic porous polytetrafluoroethylene-based membrane, the seawater hydrogen production device can be stably operated. At the same time, the water consumed by the electrolysis of hydrogen in the alkali solution hydrogen production electrolyzer also successfully maintains the osmotic pressure difference. When the migration rate of water is equal to the electrolysis rate, a new thermodynamic equilibrium is reached between seawater and the electrolyte, and continuous and stable water migration is achieved through the liquid-gas-liquid mechanism, thereby providing fresh water for electrolysis.

[0035] Furthermore, the fan blades are corrosion resistant, and therefore, the fan blades should be made of corrosion resistant materials, which can increase the service life of the variable migration area alkali solution regeneration pump.

[0036] Furthermore, a hydrophobic porous polytetrafluoroethylene-based membrane is used as a gaseous water exchange channel. A hydrophobic porous polytetrafluoroethylene-based membrane is placed between seawater and alkali solution. The transmembrane water vapor pressure difference between seawater and concentrated potassium hydroxide solution drives the transfer of water molecules. The pressure difference on the seawater side causes the spontaneous gasification of seawater, and the water vapor is transported to the alkali solution side through short-path diffusion in the hydrophobic porous polytetrafluoroethylene-based membrane. The water vapor is absorbed and reliquefied in the alkali solution. This phase change migration process realizes the in-situ generation of pure water for electrolysis in seawater, that is, the in-situ water purification of seawater without additional energy consumption is realized. The ion blocking efficiency of the hydrophobic porous polytetrafluoroethylene-based membrane reaches 100%.

[0037] Furthermore, the variable contact area control module adjusts the effective exchange migration area on both sides of the hydrophobic porous polytetrafluoroethylene-based membrane by changing the fan blade opening to control the water replenishment rate of the variable migration area alkali solution regeneration pump. After receiving the concentration signal, the fan blade opening is controlled by the variable contact area control module, and its control law is expressed as:

[0038]

[0039] in, is the fan blade opening, which ranges from [0,π]; is the PI controller, s is the Laplace operator, is the proportionality coefficient, is the integration coefficient; is the reference value of alkali solution concentration, It is the real-time alkali solution concentration.

[0040] In this embodiment, the seawater microenvironment tank is provided with a valve, and the seawater microenvironment tank and the sea are circulated through the valve to ensure that the seawater concentration in the seawater microenvironment tank is consistent with the seawater concentration reference value. The valve includes an inlet valve and a drain valve, and the speed of seawater entering and exiting the seawater microenvironment tank is controlled by changing the opening of the inlet valve and the drain valve.

[0041] Furthermore, the concentration of pure water in the seawater microenvironment tank is changed by changing the opening of the water inlet valve, and the osmotic pressure difference on both sides of the hydrophobic porous polytetrafluoroethylene-based membrane is adjusted to control the speed at which pure water in the seawater enters the alkaline hydrogen production electrolyzer, so as to achieve a constant seawater concentration in the seawater microenvironment tank, that is, consistent with the seawater concentration reference value. The control law is expressed as:

[0042]

[0043] in, is the water inlet valve opening, and its range is [0,100%]; is the PI controller, s is the Laplace operator, is the proportionality coefficient, is the integration coefficient; is the reference value of seawater concentration, is the real-time seawater concentration.

[0044] It should be understood that the seawater concentration reference value is not the seawater concentration outside at that time, because the seawater concentration in different sea areas is different. The seawater concentration reference value can be measured experimentally in the early stage. Controlling the seawater concentration in the seawater microenvironment tank near the seawater concentration reference value can better achieve the dynamic balance of water exchange and water consumption. At the same time, the set seawater concentration reference value is also different under the application of alkaline liquid hydrogen production electrolyzers of different powers. It is a reference value that can be adjusted according to actual experiments.

[0045] It should be noted that the concentration of pure water in the seawater in the seawater microenvironment tank is changed by changing the opening of the water inlet valve. The pure water in the seawater enters the variable migration area alkali solution regeneration pump through the hydrophobic porous polytetrafluoroethylene-based membrane and then enters the alkali solution hydrogen production electrolyzer.

[0046] Furthermore, the speed of seawater discharge from the seawater microenvironment tank is adjusted by changing the opening of the drain valve to control the liquid level in the seawater microenvironment tank to be constant. The control law is expressed as:

[0047]

[0048] in, is the drain valve opening, and its range is [0,100%]; is the PI controller, s is the Laplace operator, is the proportionality coefficient, is the integration coefficient; is the reference value of the internal liquid level of the seawater microenvironment tank, It is the real-time liquid level inside the seawater microenvironment tank.

[0049] In this embodiment, the concentration detection instrument measures the potassium hydroxide concentration by adopting the refraction principle, and the range of measuring the potassium hydroxide concentration is 20%-40%.

[0050] It is worth mentioning that the embodiment of the present invention also provides a control method for the seawater hydrogen production device based on the variable migration area alkali solution regeneration pump described in the above embodiment, such as Figure 2 As shown, the specific steps include:

[0051] During the electrolytic hydrogen production process of the alkali solution hydrogen production electrolyzer, the real-time alkali solution concentration in the alkali solution hydrogen production electrolyzer, the real-time seawater concentration in the seawater microenvironment tank and the real-time liquid level inside the seawater microenvironment tank are obtained in real time; the PI controller controls the opening of the water inlet valve according to the seawater concentration reference value to make the seawater concentration in the seawater microenvironment tank constant; the PI controller controls the opening of the drain valve according to the internal liquid level reference value of the seawater microenvironment tank to make the liquid level in the seawater microenvironment tank constant; the variable contact area control module controls the fan blade opening according to the alkali solution concentration reference value to adjust the effective exchange migration area on both sides of the hydrophobic porous polytetrafluoroethylene based membrane, and control the speed of gaseous water migration into the variable migration area alkali solution regeneration pump, so as to achieve a dynamic balance between the water consumption in the alkali solution hydrogen production electrolyzer and the water migration in the variable migration area alkali solution regeneration pump, and keep the alkali solution concentration in the variable migration area alkali solution regeneration pump constant; finally, the alkali solution concentration in the alkali solution hydrogen production electrolyzer maintains the optimal conductivity, and high-efficiency seawater hydrogen production is achieved.

[0052] In summary, the production of hydrogen from seawater using the device described in the present invention is beneficial to improving the dynamic performance of hydrogen production from seawater, broadening the operating range of hydrogen production from seawater, and enhancing the operating stability of the seawater hydrogen production device, so that direct hydrogen production from seawater can achieve stable and efficient operation under a wide range of power fluctuations.

[0053] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A seawater hydrogen production device based on a variable migration area alkali solution regeneration pump, characterized in that: It comprises an alkali solution hydrogen production electrolyzer, a peristaltic pump, a variable migration area alkali solution regeneration pump, a seawater microenvironment tank and a concentration detection instrument; wherein the alkali solution hydrogen production electrolyzer and the variable migration area alkali solution regeneration pump are connected via the peristaltic pump, and the variable migration area alkali solution regeneration pump is arranged in the seawater microenvironment tank; by controlling the effective exchange migration area between the variable migration area alkali solution regeneration pump and the seawater in the seawater microenvironment tank, the speed of gaseous water migration into the variable migration area alkali solution regeneration pump is adjusted, and the water consumption in the electrolytic hydrogen production process of the alkali solution hydrogen production electrolyzer and the water migration in the variable migration area alkali solution regeneration pump are controlled to achieve a dynamic balance, so as to achieve a constant concentration in the variable migration area alkali solution regeneration pump; the alkali solution concentrations in the alkali solution hydrogen production electrolyzer and the variable migration area alkali solution regeneration pump are kept dynamically consistent through the circulation operation of the peristaltic pump; the concentration detection instrument is used to measure the potassium hydroxide concentration in the variable migration area alkali solution regeneration pump; The variable migration area alkali solution regeneration pump is provided with a fan blade and a variable contact area control module for controlling the opening of the fan blade, the inner surface of the variable migration area alkali solution regeneration pump is attached with a hydrophobic porous polytetrafluoroethylene film, and the alkali solution in the variable migration area alkali solution regeneration pump is a concentrated potassium hydroxide solution with a concentration of 30%; The variable contact area control module adjusts the effective exchange migration area on both sides of the hydrophobic porous polytetrafluoroethylene based membrane by changing the fan blade opening to control the water replenishment rate of the variable migration area alkali solution regeneration pump. After receiving the concentration signal, the fan blade opening is controlled by the variable contact area control module. The control law is expressed as: Among them, α is the fan blade opening; is a PI controller, s is a Laplace operator, k p is the proportionality coefficient, k i is the integral coefficient; c * is the reference value of alkali solution concentration, c is the real-time alkali solution concentration; The seawater microenvironment tank is provided with a valve, and the seawater microenvironment tank and the sea are circulated through the valve to ensure that the seawater concentration in the seawater microenvironment tank is consistent with the seawater concentration reference value; the valve includes an inlet valve and a drain valve, and the speed of seawater entering and leaving the seawater microenvironment tank is controlled by changing the opening of the inlet valve and the drain valve; The method of controlling the speed of seawater entering and exiting the seawater microenvironment tank by changing the opening of the water inlet valve and the opening of the drain valve specifically includes: The concentration of pure water in the seawater microenvironment tank is changed by changing the opening of the water inlet valve, and the osmotic pressure difference on both sides of the hydrophobic porous polytetrafluoroethylene membrane is adjusted to control the speed at which pure water in the seawater enters the alkaline solution hydrogen production electrolyzer to achieve a constant seawater concentration in the seawater microenvironment tank. The control law is expressed as: Among them, d in is the water inlet valve opening; is a PI controller, s is a Laplace operator, k p1 is the proportionality coefficient, k i1 is the integral coefficient; c1 * is the reference value of seawater concentration, c1 is the real-time seawater concentration; The speed of seawater discharge from the seawater microenvironment tank is adjusted by changing the opening of the drain valve to control the liquid level in the seawater microenvironment tank to be constant. The control law is expressed as: Among them, d out is the drain valve opening; is a PI controller, s is a Laplace operator, k p2 is the proportionality coefficient, k i2 is the integration coefficient; h * is the reference value of the liquid level inside the seawater microenvironment tank, and h is the real-time liquid level inside the seawater microenvironment tank.

2. The seawater hydrogen production device based on a variable migration area alkali solution regeneration pump according to claim 1 is characterized in that: The alkali solution hydrogen production electrolytic cell relies on liquid exchange with a variable migration area alkali solution regeneration pump for circulating heat dissipation, and the pure water consumed in the hydrogen production process of the alkali solution hydrogen production electrolytic cell relies on the variable migration area alkali solution regeneration pump to replenish.

3. The seawater hydrogen production device based on a variable migration area alkali solution regeneration pump according to claim 1 is characterized in that: The peristaltic pump includes a suction pump and a replenishment pump, wherein the suction pump is used to extract alkali solution from the alkali solution hydrogen production electrolyzer, and the replenishment pump is used to replenish alkali solution into the alkali solution hydrogen production electrolyzer; the speed of replenishing alkali solution is greater than the speed of extracting alkali solution, so that the liquid level in the alkali solution hydrogen production electrolyzer maintains dynamic balance.

4. The seawater hydrogen production device based on a variable migration area alkali solution regeneration pump according to claim 1 is characterized in that: The hydrophobic porous polytetrafluoroethylene-based membrane is used as a gaseous water exchange channel. The hydrophobic porous polytetrafluoroethylene-based membrane is between seawater and alkali solution. The transmembrane water vapor pressure difference between seawater and concentrated potassium hydroxide solution drives the transfer of water molecules. The pressure difference on the seawater side causes the seawater to spontaneously gasify, and the water vapor is transported to the alkali solution side through short-path diffusion in the hydrophobic porous polytetrafluoroethylene-based membrane. The water vapor is absorbed and reliquefied in the alkali solution. This phase change migration process realizes the in-situ generation of pure water for electrolysis in seawater. The ion blocking efficiency of the hydrophobic porous polytetrafluoroethylene-based membrane reaches 100%.

5. The seawater hydrogen production device based on a variable migration area alkali solution regeneration pump according to claim 1 is characterized in that: The concentration detection instrument measures the concentration of potassium hydroxide by adopting the refraction principle, and the range of measuring the concentration of potassium hydroxide is 20%-40%.

6. A control method for a seawater hydrogen production device based on a variable migration area alkali solution regeneration pump according to any one of claims 1 to 5, characterized in that: Specifically include: During the electrolytic hydrogen production process of the alkali solution hydrogen production electrolyzer, the real-time alkali solution concentration in the alkali solution hydrogen production electrolyzer, the real-time seawater concentration in the seawater microenvironment tank and the real-time liquid level inside the seawater microenvironment tank are obtained in real time; the PI controller controls the opening of the water inlet valve according to the seawater concentration reference value to make the seawater concentration in the seawater microenvironment tank constant; the PI controller controls the opening of the drain valve according to the internal liquid level reference value of the seawater microenvironment tank to make the liquid level in the seawater microenvironment tank constant; the variable contact area control module controls the fan blade opening according to the alkali solution concentration reference value to adjust the effective exchange migration area on both sides of the hydrophobic porous polytetrafluoroethylene based membrane, and control the speed of gaseous water migration into the variable migration area alkali solution regeneration pump, so as to achieve a dynamic balance between the water consumption in the alkali solution hydrogen production electrolyzer and the water migration in the variable migration area alkali solution regeneration pump, and keep the alkali solution concentration in the variable migration area alkali solution regeneration pump constant; finally, the alkali solution concentration in the alkali solution hydrogen production electrolyzer maintains the optimal conductivity, and hydrogen production from seawater is achieved.

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