High-efficiency low-consumption long-life alkali liquor circulating system for hydrogen production by alkaline water electrolysis

Abstract

The invention discloses a high-efficiency low-consumption long-life alkali liquor circulating system for hydrogen production by alkaline water electrolysis, which comprises a cathode side and an anode side, on the anode side, an alkaline water electrolysis hydrogen production device is connected with a catalytic conversion module, and the catalytic conversion module is connected to a gas-liquid separation module; liquid in the gas-liquid separation module is connected to the electrolytic bath through an alkali liquor circulation module, an alkali liquor circulation heat exchanger and an alkali liquor filter in sequence; for the cathode side, the alkaline water electrolysis hydrogen production device is connected with a gas-liquid separation module, and the liquid output end of the gas-liquid separation module is connected to the electrolytic bath through an alkaline liquid circulation module, an alkaline liquid circulation heat exchanger and an alkaline liquid filter in sequence; and the anode side and the cathode side are respectively provided with corresponding alkali liquor control modules. According to the invention, the adaptability of the alkaline water electrolysis system in a wide load fluctuation range is improved, the corrosion of oxygen free radicals to system equipment is eliminated, the power consumption of an alkali liquor circulating pump is reduced, and the economical efficiency of the alkaline water electrolysis hydrogen production system is improved.

Description

Technical Field

[0001] The present invention relates to the field of alkaline solution circulation systems for producing hydrogen by electrolysis of alkaline water, and more specifically to a high-efficiency, low-consumption, and long-life alkaline solution circulation system for producing hydrogen by electrolysis of alkaline water. Background Art

[0002] As a clean and efficient energy carrier, hydrogen is considered an important component of the future energy system. Hydrogen production technologies are categorized into blue hydrogen, gray hydrogen, and green hydrogen, depending on the production process and by-products. Among the numerous hydrogen production technologies, water electrolysis has garnered widespread attention due to its environmental and sustainability characteristics. Among these, alkaline water electrolysis hydrogen production technology is the most mature due to its low equipment costs and long history of development. Its industrialized economy is extensive, making it suitable for large-scale hydrogen production in the industrialized process. The stability of the alkaline water electrolysis hydrogen production process also supports coupling with intermittent renewable energy sources such as solar and wind power, alleviating pressure on the power grid.

[0003] Currently, alkaline water electrolysis hydrogen production systems suffer from a common problem: simplistic feedback control of the gas-liquid separator's liquid level regulation. This makes it difficult to adapt promptly to sudden pressure fluctuations caused by instantaneous flow. This leads to significant liquid level fluctuations within the separator, increasing gas retention in the liquid and reducing system safety. Furthermore, within the alkali solution circulation loop, the electrolytic cell load constantly fluctuates. Furthermore, components such as the circulating pump and the piping layout can cause uneven alkali solution flow, leading to imbalanced liquid levels in the anode and cathode separators, causing pressure drop fluctuations across the separators and reducing alkali solution separation efficiency.

[0004] In the process of hydrogen production by alkaline water electrolysis, due to the high potential characteristics of the oxygen evolution reaction and the complex interface environment, hydroxyl radicals such as , superoxide anion free radical Byproducts such as oxygen free radicals (OFRs) are highly reactive and possess strong oxidizing power. As the circulating alkali solution flows into the electrolysis system components, they adhere to the system's internal surfaces and oxidize, inducing pitting and intergranular corrosion of the system's equipment materials. This significantly reduces the system life and threatens the safe operation of the alkaline hydrogen electrolysis system. As the electrolysis system continues to operate, the OFRs generated at the anode electrode accumulate, causing the oxide layer on the equipment surface to detach and ions to precipitate, degrading the quality of the circulating alkali solution and the purity of the collected gas. The deposited OFRs trigger oxygen evolution side reactions, reducing the effective current available for the electrolysis reaction. Some OFRs corrode the electrode surface and diaphragm, increasing the concentration overpotential, increasing energy consumption, and reducing electrolysis efficiency. Most existing alkaline water electrolysis hydrogen production systems focus on the purity of the gas from downstream equipment, focusing solely on the removal of impurities in the separated gas. They fail to consider the challenges of oxidizing species carried by the circulating alkali solution. Consequently, they neglect to address the root causes of extending the life of the alkaline water electrolysis system and improving its efficiency. In particular, alkaline water electrolysis hydrogen production systems have relatively long operation and maintenance cycles. Long-term corrosion from oxygen free radicals can damage equipment, leading to pressure fluctuations and alkali leaks. The inability to observe and predict the impact of oxygen free radical corrosion in a closed environment is undoubtedly a hidden danger. Summary of the Invention

[0005] In order to achieve these purposes and other advantages according to the present invention, the present invention provides a high-efficiency, low-consumption, long-life alkali solution circulation system for hydrogen production by alkaline water electrolysis, comprising a cathode side and an anode side, wherein both the cathode side and the anode side are provided with a gas-liquid separation module, an alkali solution circulation module, an alkali solution circulation heat exchanger and an alkali solution filter, the alkali solution circulation module is an alkali solution circulation pump, and the anode side further includes a catalytic conversion module; wherein, For the anode side, the anode side output end of the alkaline water electrolysis hydrogen production device is connected to the input end of the catalytic conversion module, the output end of the catalytic conversion module is connected to the input end of the gas-liquid separation module, the gas-liquid separation module performs gas-liquid separation on the catalyzed gas-liquid mixture, and the liquid output end of the gas-liquid separation module is connected to the electrolyzer of the alkaline water electrolysis hydrogen production system through the alkaline liquid circulation module, the alkaline liquid circulation heat exchanger and the alkaline liquid filter in sequence to form a closed-loop circulation system; On the cathode side, the cathode side output end of the alkaline water electrolysis hydrogen production device is connected to the input end of the gas-liquid separation module, and the liquid output end of the gas-liquid separation module is connected to the electrolyzer of the alkaline water electrolysis hydrogen production system through the alkaline liquid circulation module, the alkaline liquid circulation heat exchanger and the alkaline liquid filter in sequence to form a closed-loop circulation system; Corresponding alkali liquid control modules are respectively provided on the anode side and the cathode side, and the input ends of the gas-liquid separators on the anode side and the cathode side are respectively connected to the corresponding alkali liquid control modules, and the alkali liquid control module includes an alkali liquid circulation controller, a third solenoid valve and an alkali replenishing tank; the gas-liquid separator on the cathode side and the gas-liquid separator on the anode side are connected through a U-shaped tube, and the alkali liquid circulation controller starts the alkali replenishing tank according to the change signal of the height on both sides of the liquid column in the U-shaped tube, and controls the alkali liquid inflow into the cathode side alkali replenishing tank and the anode side alkali replenishing tank according to the height difference of the liquid column in the U-shaped tube, so as to keep the liquid level on both sides of the U-shaped tube consistent.

[0006] Preferably, the gas-liquid separation module includes a gas-liquid separator, and both the cathode side and the anode side of the alkaline water electrolysis hydrogen production device are provided with a self-adaptive gas-liquid separator; The gas-liquid separator includes a separation cylinder, a spiral plate, a mist capture screen and a reset device, wherein a gas-liquid separation feed port is provided on the side wall of the separation cylinder, a gas-liquid separation discharge port is provided at the bottom, and a catalytic conversion exhaust port is provided on the top. The catalytic conversion exhaust port is connected to the gas-liquid separation discharge port through an exhaust channel. The gas-liquid separation feed port is connected to the electrolyzer of the electrolytic hydrogen production device, and the gas-liquid separation discharge port is connected to the alkaline liquid circulation device. The spiral plate is located at the place where the gas-liquid separation feed port enters the separation cylinder, and spirally surrounds the outside of the exhaust channel. A liquid collecting device is provided below the spiral plate, and the spiral plate is movably arranged outside the exhaust channel through the reset device.

[0007] Preferably, the height between the top of the spiral plate and the top of the inner side of the separation cylinder is H, which is calculated using the following formula:

[0008] Where V is the volume flow rate of alkali solution at the gas-liquid separation feed port, H is the length of the separation device when the volume flow rate of alkali solution is V; M1 is the correction coefficient; Q is the heat generation of the electrolytic cell under the current load, unit is W; is the density of the alkali solution, in kg / m 3 ; is the specific heat capacity of alkali solution at constant pressure, in J / kg.K; is the temperature difference between the inlet and outlet of the electrolytic cell, with the unit of K. The reset device here is a spring, k is the elastic coefficient of the spring, and k is expressed as the ratio of the weight of the alkali solution in the liquid collecting device to the deformation displacement of the spring within the range of elastic deformation; g is the acceleration of gravity, with the unit of N / kg.

[0009] Preferably, the input ends of the alkali solution circulation pumps on the anode side and the cathode side are respectively connected to the corresponding alkali solution control modules. For the anode side, the input end of the catalytic conversion module is also connected to the alkali solution control module. For the alkali solution circulation pump, the alkali solution circulation controller starts the alkali replenishing tank to replenish alkali solution to the pipeline or controls the pipeline to discharge liquid to the alkali replenishing tank according to the flow control of the alkali solution circulation pump; Preferably, the catalytic conversion module comprises a plurality of catalytic conversion branches arranged in parallel, and each catalytic conversion branch is provided with an oxygen free radical catalytic converter; A rotary valve is set at the inlet of each catalytic conversion branch, and a solenoid valve is set at the outlet. Each oxygen free radical catalytic converter is correspondingly provided with a flow meter to monitor its flow. Concentration detector; The outlets of all catalytic conversion branches are also connected to the gas-liquid separator through solenoid valves, and the outlets are also connected to the alkali replenishment tank through solenoid valves. The inlets of all catalytic conversion branches are connected to the sewage system through solenoid valves, and the inlets are also connected to the electrolyzer through solenoid valves.

[0010] Preferably, the oxygen free radical catalytic converter includes a shell, a sleeve and a catalytic unit, the sleeve is coaxially sleeved in the shell, the sleeve and the shell are both horizontally arranged, and one end of the sleeve is fixed to one end of the shell provided with a catalytic conversion feed port, the catalytic conversion feed port is connected to the anode side outlet of the alkaline water electrolysis hydrogen production device, the side wall of the sleeve and the side wall of the shell are separated by a certain distance, the upper side of the side wall in the sleeve is provided with a catalytic conversion exhaust port, the lower side of the side wall is provided with a catalytic conversion liquid discharge port, the inner side wall of the sleeve is staggered with a number of baffles, and the shell is further provided with a number of catalytic units along its length direction at the rear side of the sleeve, each catalytic unit is divided into an upper layer and a lower layer, and the two are separated by a certain distance, the upper layer of the catalytic unit and the catalytic conversion exhaust port are on the same side, and the gas separated and discharged through the catalytic conversion exhaust port is subjected to the treatment. and To capture and eliminate, the lower layer of the catalytic unit and the catalytic conversion outlet are on the same side, and the alkali solution discharged through the outlet is Capture and eliminate.

[0011] Preferably, the catalytic units are respectively a first catalytic unit, a second catalytic unit and a third catalytic unit along the gas-liquid flow direction; The first catalytic unit includes an alkaline liquid catalytic unit equipped with a Pt / C catalyst and a porous titanium gas diffusion catalytic coating for preferentially decomposing , to prevent subsequent As the high temperature alkali solution volatilizes and decomposes Corrosion to metal pipes and sealing materials; The second catalytic unit includes an alkaline liquid catalytic coating layer carrying a Mn / C catalyst and a Pt / C catalyst, and a porous titanium gas diffusion catalytic coating layer with a surface sulfonation treatment; The third catalytic unit includes a Alkaline liquid catalytic coating and porous gas diffusion catalytic coating.

[0012] Preferably, the inner wall of the shell is provided with catalytic conversion baffles at the corresponding positions of the catalytic conversion exhaust port and the catalytic conversion drain port, respectively. The catalytic conversion baffles can block part of the catalytic conversion exhaust port or part of the catalytic conversion drain port. A rotary valve is provided at one end of the sleeve where the catalytic conversion feed port is opened. By controlling the rotation of the rotary valve, the sleeve is driven to rotate, thereby controlling the flow area of the catalytic conversion exhaust port or the catalytic conversion drain port.

[0013] Preferably, the rotary valve includes a valve core and a sealing assembly. The valve core is installed at one end of the catalytic conversion feed port of the rotatable sleeve. A layer of sealing assembly is provided between the valve core and the sleeve to prevent alkali solution from splashing. The valve core is connected to a servo motor to drive the valve core to rotate.

[0014] Preferably, the catalytic conversion module is used as follows: S1: The electrolyzer is running, and the gas-liquid mixture (generated oxygen and circulating alkali solution) enters the catalytic conversion module from the anode side outlet; S2. Control the operation of one of the oxygen free radical catalytic converters and monitor the alkali solution flow rate at the outlet of the oxygen free radical catalytic converter through a flow meter. If the flow rate is lower than half of the circulating alkali solution demand of the electrolyzer under the current operating conditions, control the rotary valve at the inlet of the branch to increase the flow rate of the gas-liquid mixture. When the operating conditions of the alkaline electrolyzer fluctuate, causing unstable flow rate of the gas-liquid mixture, and the flow meter detects that the content of a branch is too high, control the rotary valve at the inlet of the branch to reduce the flow rate, open the solenoid valves at the outlets of all catalytic conversion branches, connect the recovery tank to release the pressure, and readjust the inlet rotary valve after the system stabilizes. S3, control one of the oxygen free radical catalytic converters to operate, by The concentration detector monitors the oxygen free radical content at the outlet. If the oxygen free radical exceeds the standard, the operation and maintenance mode is entered, and the operation is switched to another oxygen free radical catalytic converter. The solenoid valves at the outlet of the alkali tank and the inlet of the sewage system are opened, and alkali solution is introduced to backwash the oxygen free radical catalytic converter with excessive oxygen free radicals, and then the alkali solution is led to the sewage system; if If the concentration detector detects that the content of oxygen free radicals is still exceeding the standard, the corresponding branch solenoid valve will be closed and the catalyst will be replaced.

[0015] The present invention has at least the following beneficial effects: (1) The present invention sets a U-shaped tube to connect the liquid level near the gas-liquid separation outlet of the gas-liquid separator on the cathode side and the anode side, thereby ensuring the balance of the liquid level on both sides. At the same time, the U-shaped tube is linked to the solenoid valve on the outlet side of the gas-liquid separation outlet. When the load changes too much or too quickly, causing the liquid column in the U-shaped tube to be too high, the solenoid valve controls the opening of the alkali replenishing tank to adjust the alkali flow rate of the alkali circulation loop to ensure that the pressure difference between the cathode side and the anode side remains balanced. Compared with the gravity sedimentation separation method of the prior art, which has a fixed structure and poor pressure regulation, the present invention can adjust the circulating alkali flow rate, thereby stabilizing the working stability of the gas-liquid separator and improving the gas-liquid separation efficiency, thereby improving the electrolysis efficiency of the alkaline water electrolysis hydrogen production system.

[0016] (2) The self-adaptive gas-liquid separator described in the present invention utilizes the linkage of the separation device (spiral plate) and the liquid collecting device to change the gravity of the alkali liquid in real time according to the change of the volume flow rate of the alkali liquid in the mixture at the gas-liquid separation feed inlet and to achieve vertical sliding of the separation device by adjusting the relative height of the separation device in the separation cylinder, thereby adjusting the size of the volume of the gas-liquid mixing space near the gas-liquid separation feed inlet and the incident angle of the gas-liquid mixture. This effectively breaks through the technical barriers of the existing gas-liquid separator of the alkaline water electrolysis hydrogen production system, which has a narrow applicable working condition range and poor flexibility. The application of the gravitational potential energy of the alkali liquid makes it self-adaptive to the characteristics of the wide power operation of the industrial-scale alkaline water electrolysis system, thereby improving the gas-liquid separation efficiency and ensuring the high efficiency of the operation of the alkaline water electrolysis hydrogen production system.

[0017] (3) The oxygen free radical elimination catalytic converter of the present invention utilizes the linkage of the rotary valve and the sleeve to change the inlet volume flow of the gas-liquid mixture in real time according to the volume flow of the gas-liquid mixture output by the electrolyzer, and changes the contact area with the catalytic conversion partition through the rotation of the connected sleeve to adjust the flow rate of the gas and the alkaline solution, thereby ensuring the stable flow of gas and liquid in the catalytic conversion module under different working conditions, improving the catalytic conversion efficiency, and effectively breaking through the technical barriers of the narrow applicable working condition range and poor flexibility brought by the fixed structure of the existing alkaline water electrolysis hydrogen production system equipment, and comprehensively improving the operation cycle of the electrolysis hydrogen production system components within a wide load range.

[0018] (4) The present invention sets a catalytic conversion module on the anode side of the alkaline water electrolysis hydrogen production system. The two catalytic converters of the catalytic conversion module operate alternately to capture oxygen free radicals carried in the gas and liquid in a graded manner. A backwash module is set at the outlet of the catalytic conversion module, and the control of the branch and main solenoid valves is combined to achieve stable operation under load changes, thereby improving the service life of the catalytic converter. The concentration detector can realize the operation detection of the catalytic efficiency of the oxygen free radical catalytic converter, which is convenient for operation and maintenance.

[0019] Other advantages, objectives and features of the present invention will be reflected in part from the following description and will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the alkali solution circulation system of the present invention; Figure 2 This is a three-dimensional diagram of the gas-liquid separator of the present invention; Figure 3 This is a cross-sectional view of the gas-liquid separator of the present invention; Figure 4 This is a gas-liquid separation principle diagram of the gas-liquid separator of the present invention; Figure 5 A graph showing the relationship between the vertical drop distance of the spiral plate in the gas-liquid separator of the present invention and the volume flow rate of the alkali solution introduced into the mixture; Figure 6 Schematic diagram of the structure of the catalytic conversion module of the present invention; Figure 7 is a perspective view of the oxygen free radical catalytic converter of the present invention; Figure 8 is a cross-sectional view of an oxygen free radical catalytic converter of the present invention; In the picture: 1-electrolyzer; 2-rectifier transformer; 3-alkali filter; 4-alkali feed tank; 5-alkali circulation controller; 6-alkali circulation heat exchanger; 7-third solenoid valve; 9-alkali circulation pump; 10-gas-liquid separator; 11-catalytic converter module; 12-purification equipment; 13-gas scrubber; 10-1-gas-liquid separation feed port; 10-2-separation cylinder; 10-3-spiral plate; 10-4-connecting rod; 10-5-gas-liquid separation partition; 10-6-gas-liquid separation drain port; 10-7-filter; 10-8-reset device; 10-9-mist capture screen; 10-10-gas-liquid separation exhaust port; 23-first solenoid valve; 24-second solenoid valve; 25-fourth Solenoid valve; 26-fifth solenoid valve; 27-sixth solenoid valve; 28-first rotary valve; 29-second rotary valve; 30-first flow meter; 31-second flow meter; 32-first oxygen free radical catalytic converter; 33-second oxygen free radical catalytic converter; 34-sealing assembly; 35-housing; 36-catalytic unit; 37-outlet; 38-sleeve; 39-catalytic conversion feed port; 40-valve core; 41-servo motor; 42-connecting hole; 43-baffle; 44-catalytic conversion partition; 45-catalytic conversion exhaust port; 46-catalytic conversion liquid discharge port. DETAILED DESCRIPTION

[0021] The present invention will be described in further detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0022] The following description is intended to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are for illustrative purposes only, and those skilled in the art will readily appreciate other obvious variations. The basic principles of the present invention defined in the following description may be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not depart from the spirit and scope of the present invention.

[0023] It should be understood by those skilled in the art that, in the disclosure of the present invention, the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0024] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the elements may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0025] like Figure 1 As shown, a preferred embodiment of the present invention provides a high-efficiency, low-consumption, and long-life alkali solution circulation system for producing hydrogen by alkali water electrolysis. It includes a cathode side and an anode side, wherein both the cathode side and the anode side are provided with a gas-liquid separation module, an alkaline solution circulation module, an alkaline solution circulation heat exchanger 6 and an alkaline solution filter 3, and the anode side also includes a catalytic conversion module 11; wherein, For the anode side, the anode side output end of the alkaline water electrolysis hydrogen production device is connected to the input end of the catalytic conversion module 11, and the output end of the catalytic conversion module 11 is connected to the input end of the gas-liquid separation module. The gas-liquid separation module performs gas-liquid separation on the catalyzed gas-liquid mixture. The liquid output end of the gas-liquid separation module is connected to the electrolyzer 1 of the alkaline water electrolysis hydrogen production system in sequence through the alkaline liquid circulation module, the alkaline liquid circulation heat exchanger 6 and the alkaline liquid filter 3 to form a closed-loop circulation system; For the cathode side, the cathode side output end of the alkaline water electrolysis hydrogen production device is connected to the input end of the gas-liquid separation module, and the liquid output end of the gas-liquid separation module is connected to the electrolytic cell of the alkaline water electrolysis hydrogen production system through the alkaline liquid circulation module, the alkaline liquid circulation heat exchanger 6 and the alkaline liquid filter 3 in sequence to form a closed-loop circulation system; Corresponding alkali liquid control modules are respectively provided on the anode side and the cathode side, and the input ends of the gas-liquid separators on the anode side and the cathode side are respectively connected to the corresponding alkali liquid control modules, and the alkali liquid control module includes an alkali liquid circulation controller 5, a third solenoid valve 7 and an alkali supplement tank 4; the gas-liquid separator on the cathode side and the gas-liquid separator on the anode side are connected through a U-shaped tube, and the alkali liquid circulation controller 5 starts the alkali supplement tank 4 according to the change signal of the height on both sides of the liquid column in the U-shaped tube, and controls the alkali liquid inflow into the cathode side alkali supplement tank and the anode side alkali supplement tank according to the height difference of the liquid column in the U-shaped tube, so as to keep the liquid level on both sides of the U-shaped tube consistent.

[0026] When the electrolytic cell is running, on the anode side, a gas-liquid mixture consisting of the gas generated at the anode and the circulating alkali liquid introduced into the electrolytic cell is discharged from the electrolytic cell outlet, and the gas-liquid mixture enters the catalytic conversion module. The oxygen free radical catalytic converter in the catalytic conversion module captures the by-product oxygen free radicals through its internal catalyst, thereby reducing the corrosion of the oxygen free radicals on the downstream equipment; the gas-liquid mixture treated by the catalytic conversion module then enters the gas-liquid separation module for gas-liquid separation; the liquid after gas-liquid separation is pressurized by the alkali liquid circulation module (alkali liquid circulation pump 9), cooled by the alkali liquid circulation heat exchanger 6, and then filtered by the alkali liquid filter 3, and finally reaches the electrolytic cell, forming a closed-loop circulation system. On the cathode side, a gas-liquid mixture consisting of the gas generated at the cathode and the circulating alkali solution entering the electrolytic cell is discharged from the electrolytic cell outlet and enters the gas-liquid separation module for gas-liquid separation. The liquid after gas-liquid separation is pressurized by the alkali circulation module (alkali circulation pump 9), cooled by the alkali circulation heat exchanger 6, and filtered by the alkali filter 3 before finally reaching the electrolytic cell, forming a closed-loop circulation system. Rectifier transformer 2 provides power to the electrolytic cell by stepping down the high voltage of the grid.

[0027] The connection relationship between the gas-liquid separator and the alkali solution control module on the anode side is as follows: Figure 1 As shown, the input end of the third solenoid valve 7 is connected to the alkali feed tank 4, and the output end of the third solenoid valve 7 is connected to the input end of the gas-liquid separator 10 via a flowmeter. The alkali feed tank 4 and the third solenoid valve 7 are both connected to the alkali liquid circulation controller 5. The alkali liquid circulation controller 5 activates the alkali feed tank 4 based on the change signal of the height of the liquid column on both sides of the U-shaped tube, and controls the amount of alkali liquid flowing into the gas-liquid separator from the cathode-side alkali feed tank and the anode-side alkali feed tank based on the height difference of the liquid column in the U-shaped tube, maintaining the consistency of the liquid level on both sides of the U-shaped tube, thereby maintaining stable liquid levels in the cathode-side gas-liquid separator and the anode-side gas-liquid separator when the load of the electrolytic cell changes over a wide load range.

[0028] In another technical solution, Figure 2-5 As shown, the gas-liquid separation module includes a gas-liquid separator 10; both the cathode side and the anode side of the alkaline water electrolysis hydrogen production device are provided with self-adaptive gas-liquid separators; The gas-liquid separator 10 includes a separation cylinder 10-2, a spiral plate 10-3, a mist capture screen 10-9 and a reset device, wherein the side wall of the separation cylinder 10-2 is provided with a gas-liquid separation feed port 10-1, the bottom is provided with a gas-liquid separation discharge port 10-6, and the top is provided with a gas-liquid separation exhaust port 10-10, the gas-liquid separation exhaust port 10-10 is connected to the gas-liquid separation discharge port 10-6 through an exhaust channel, the gas-liquid separation feed port 10-1 is connected to the catalytic conversion module, the The gas-liquid separation discharge port 10-6 is connected to the alkali liquid circulation device (alkali liquid circulation pump 9), and the spiral plate 10-3 is located at the gas-liquid separation feed port 10-1 entering the separation cylinder 10-2, and is spirally wrapped around the outside of the exhaust channel. A liquid collecting device is provided under the spiral plate 10-3, and the spiral plate 10-3 is movably arranged outside the exhaust channel. The gas-liquid separation discharge port of the gas-liquid separator 10 on the cathode side and the gas-liquid separation discharge port of the gas-liquid separator 10 on the anode side are connected through a U-shaped tube.

[0029] The columnar shape of the separation cylinder 10-2 ensures uniform gas-liquid pressure distribution at the bottom of the cylinder 10-2, making it less susceptible to local flow disturbances. This helps maintain liquid level balance in the cathode and anode gas-liquid separators and reduces the risk of downtime due to excessive liquid level differences. The mist capture screen 10-9 is positioned at the gas-liquid separation exhaust port 10-10 to separate and capture alkaline mist impurities contained in the exhaust gas.

[0030] The gas-liquid separation feed port 10-1 is used to introduce a mixture of alkali liquid and gas into the separation cylinder 10-2. The liquid collecting device structure is funnel-shaped and consists of a gas-liquid separation partition 10-5 and a filter screen 10-7. The spiral plate 10-3 is located at the gas-liquid separation feed port 10-1 entering the separation cylinder 10-2, and is used to form a vortex of the gas-liquid mixture, accelerate the gas-liquid mixture under the action of centrifugal force, and at the same time increase the separation path, improve the separation efficiency, and reduce the vertical distance the liquid falls so that its flow velocity and pressure remain relatively stable. The gas-liquid separation partition 10-5 is funnel-shaped, and the funnel-shaped structure is a tapered form, which is conducive to increasing centrifugal acceleration, accelerating air flow speed, and effectively preventing alkali solution from being entrained secondary, which helps to concentrate the alkali solution to the bottom. The wall and bottom of the partition are provided with filter screens to slow down the discharge rate of alkali solution and ensure the docking stability of the separation device; filter screens with different gradient pores are set at the bottom to make the bubbles in the alkali solution gather and separate, realizing secondary gas-liquid separation to reduce the influence of gas content in the alkali solution circulation on the electrolysis efficiency.

[0031] Filter screens 10-7 are laid on the bottom and sides of the gas-liquid separation partition 10-5. The gas-liquid separation partition 10-5 is fixedly connected to the spiral plate 10-3 via a connecting rod 10-4. The gas-liquid separation partition 10-5 is used to collect the separated alkali solution, and the filter screen is used to improve the alkali solution separation accuracy and reduce the bubble content of the discharged alkali solution. The outer diameter of the spiral plate 10-3 is less than or equal to the maximum diameter of the gas-liquid separation partition 10-5, and the outer diameter of the spiral plate 10-3 is less than or equal to the inner diameter of the separation cylinder 10-2. When the outer diameter of the spiral plate 10-3 is less than the inner diameter of the separation cylinder 10-2, a baffle with a height of 0.5-1mm is installed at the outer diameter to reduce the amount of alkali solution thrown out, thereby improving the liquid collection efficiency.

[0032] The volume flow rate of the alkali solution at the gas-liquid separation feed port 10-1 affects the residence height of the separation device when the liquid in the liquid collecting device maintains relative equilibrium. The gravity of the liquid controls the relative height of the separation device. It can also be used to control the spatial volume at the outlet of the gas-liquid separation feed port 10-1 and the rate of the gas-liquid mixture, as well as the initial angle of incidence. If a fixed spiral plate 10-3 is used, the spatial volume of the feed port outlet remains unchanged, which will make it difficult for the droplets to settle or the rotational gas velocity is low, resulting in poor ability of the gas to carry the alkali solution into the separation cylinder 10-2. At the same time, the total length of the exhaust channel remains unchanged, which will also affect the stability of the exhaust rate to a certain extent. In the present application, the spiral plate 10-3 is movably arranged outside the exhaust duct by a reset device 10-8, and the reset device 10-8 can be set as a spring. The combined effect of the spring expansion force and the gravity of the collected alkali solution enables the spiral plate 10-3 to be moved vertically in the separation cylinder 10-2. When the relative height of the spiral plate 10-3 in the separation cylinder 10-2 is the lowest, the efficiency of alkali solution removal is the highest. When the alkaline water hydrogen production electrolyzer is operated at a high load, its gas-liquid separation efficiency is higher than 92%. A liquid collecting device is connected below the spiral plate 10-3 to collect the alkali solution after separation. It can be linked in real time with the volume and weight of the gas-liquid mixture generated by the change in the electrolyzer load. By collecting the volume and weight change of the alkali solution after separation, the spiral plate 10-3 is driven to move up and down in the separation cylinder 10-2, realizing adaptive regulation of separation efficiency as the electrolyzer load changes.

[0033] When the electrolytic cell is running, a gas-liquid mixture consisting of the gas generated at the electrode and the circulating alkali liquid introduced into the electrolytic cell is discharged from the electrolytic cell outlet. The gas-liquid mixture enters the separation cylinder 10-2 from the gas-liquid separation feed port 10-1, and undergoes preliminary gas-liquid separation through the spiral plate 10-3. After passing through the spiral plate 10-3, part of the alkali liquid and alkali mist gather on the inner wall surface of the liquid collecting device. The preliminarily separated alkali liquid moves downward along the inclined surface of the liquid collecting device and gradually settles. It is discharged through the filter screen 10-7 installed on the side and bottom surface and enters the bottom of the separation cylinder 10-2. During this period, the filter screen will control the discharge speed of the alkali liquid and perform secondary separation on the small-sized bubbles in the alkali liquid. After leaving the liquid collecting device, the gas moves upward and is discharged through the gas-liquid separation exhaust port 10-10. The gas preliminarily separated by the spiral plate 10-3 still carries a large amount of small-particle alkali liquid and alkali mist. In order to reduce the impact of alkali mist impurities on the downstream equipment of the electrolysis system and improve the gas purity, a wire mesh mist capture screen 10-9 is installed at the gas-liquid separation exhaust port 10-10. The alkali mist and small-particle alkali liquid are captured by the mist capture device and gathered under the device. The gravitational potential energy generated by the agglomerates of attached alkali mist and liquid droplets can effectively control the content of alkali liquid impurities at the gas-liquid separation exhaust port.

[0034] In another technical solution, Figure 5 The graph is a graph showing the change in the relative height H of the spiral plate in the separator cylinder 10-2 as the volume flow rate of the alkali solution in the gas-liquid mixture is introduced. Under different workloads of the alkaline water hydrogen production electrolyzer, the volume flow rate of the alkali solution in the gas-liquid mixture introduced into the separator is different.

[0035] The height of the top of the spiral plate 10-3 from the inner top of the separation cylinder 10-2 is H, which is calculated using the following formula:

[0036] Where V is the volume flow rate of alkali solution at the gas-liquid separation feed port, H is the length of the separation device when the volume flow rate of alkali solution is V; M1 is the correction coefficient; Q is the heat generation of the electrolytic cell under the current load, unit is W; is the density of the alkali solution, in kg / m 3 ; is the specific heat capacity of alkali solution at constant pressure, in J / kg.K; is the temperature difference between the inlet and outlet of the electrolytic cell, with the unit of K. The reset device here is a spring, k is the elastic coefficient of the spring, and k is expressed as the ratio of the weight of the alkali solution in the liquid collecting device to the deformation displacement of the spring within the range of elastic deformation; g is the acceleration of gravity, with the unit of N / kg.

[0037] The adaptive control process of the gas-liquid separator includes the following steps: A gas-liquid mixture consisting of alkali liquor and hydrogen or oxygen is introduced into the gas-liquid separation feed port 10-1 and enters the spiral plate 10-3 for preliminary gas-liquid separation. The separated alkali liquor is collected and enters the liquid collecting device.

[0038] As the volume of alkali solution in the liquid collection device increases, the liquid level rises, and the alkali solution is gradually discharged through the filter structure. When the amount of separated alkali solution collected and discharged per unit time reaches dynamic equilibrium, the weight of the alkali solution in the liquid collection device pulls the separation device to slide vertically, controlling the separation device to maintain a relatively constant height. During this process, the alkali content of the gas passing through the gas-liquid separation exhaust port is controlled to be within 0.5%-3%. When the load decreases or other reasons cause the volume flow rate of the gas-liquid mixture at the gas-liquid separation feed port 10-1 to decrease, the amount of separated alkali solution collected per unit time is less than the discharge amount, the alkali solution weight of the liquid collection device decreases, and the spring force resets the device. The hydrogen or oxygen after gas-liquid separation is discharged through the gas-liquid separation exhaust port and enters the gas scrubber 13 and purification equipment 12.

[0039] The liquid collecting device adjusts the relative height of the separation device in the separation cylinder 10-2 according to the volume flow rate of the alkali liquid introduced into the gas-liquid mixture, specifically: In the initial state, the volume flow rate of the alkali liquid introduced into the gas-liquid mixture is V0, and the vertical height from the top of the separation device to the top inner wall of the separation cylinder 10-2 is H0.

[0040] When the volume flow rate of the alkali solution introduced into the gas-liquid mixture is V1, the vertical height H1 of the top of the separation device from the top inner wall of the separation cylinder 10-2 is calculated, and the difference between H1 and H0 is calculated. , adjusted by spring structure , so that the vertical height of the separation device in the separation cylinder 10-2 is H1.

[0041] In another technical solution, the catalytic conversion module 11 includes multiple catalytic conversion branches arranged in parallel, each catalytic conversion branch is provided with an oxygen free radical catalytic converter and a rotary valve, and each oxygen free radical catalytic converter is correspondingly provided with a flow meter to monitor its flow rate, and an H2O2 concentration detector is provided at the outlet of each of the two catalytic conversion branches.

[0042] The outlets of all catalytic conversion branches are also connected to the gas-liquid separator through solenoid valves, and the outlets are also connected to the alkali replenishment tank through solenoid valves. The inlets of all catalytic conversion branches are connected to the sewage system through solenoid valves, and the inlets are also connected to the electrolyzer through solenoid valves.

[0043] The catalytic conversion module is also connected to an alkali liquid control module, which has the same structure as the alkali liquid control module of the gas-liquid separator. Specifically, the input end of the third solenoid valve 7 is connected to the alkali replenishment tank 4, and the output end of the third solenoid valve 7 is connected to the output end of the catalytic conversion module through a flow meter. The alkali replenishment tank 4 and the third solenoid valve 7 are both connected to the alkali liquid circulation controller 5.

[0044] Specifically, such as Figure 6 As shown, the present application provides a situation where the catalytic conversion module 11 includes two catalytic conversion branches, the oxygen free radical catalytic converters are arranged in parallel, and during operation, at least one oxygen free radical catalytic converter is working; the first catalytic conversion branch is provided with a first rotary valve 28, a first oxygen free radical catalytic converter 32, and a first flowmeter 30 and a first solenoid valve 23 for detecting the flow before and after the first oxygen free radical catalytic converter, and the second catalytic conversion branch is provided with a second rotary valve 29, a second oxygen free radical catalytic converter 33, and a second flowmeter 31 and a second solenoid valve 24 for detecting the flow before and after the second oxygen free radical catalytic converter, and the outlets of the two catalytic conversion branches are also connected to the gas-liquid separator 10 through the fourth solenoid valve 25, and the outlets are also connected to the alkali replenishing tank through the third solenoid valve 7, the inlets of the two catalytic conversion branches are connected to the sewage system through the sixth solenoid valve 27, and the inlets are also connected to the electrolyzer 1 through the fifth solenoid valve 26.

[0045] In another technical solution, Figure 7-8 As shown, the oxygen free radical catalytic converter includes a shell 35, a sleeve 38 and a catalytic unit 36. The sleeve 38 is coaxially sleeved in the shell 35. The sleeve 38 and the shell 35 are both horizontally arranged, and one end of the sleeve 38 is fixed to one end of the shell 35 provided with a catalytic conversion feed port 39. The catalytic conversion feed port 39 is connected to the anode side outlet of the alkaline water electrolysis hydrogen production device. The side wall of the sleeve 38 and the side wall of the shell are separated by a certain distance. The upper side of the side wall in the sleeve 38 is provided with a catalytic conversion exhaust port 45, and the lower side of the side wall is provided with a catalytic conversion liquid discharge port 46. A number of baffles 43 are staggeredly arranged on the inner side wall of the sleeve 38. A number of catalytic units are also provided in the shell 35 along its length direction at the rear side of the sleeve. Each catalytic unit is divided into an upper layer and a lower layer, and the two are separated by a certain distance. The upper layer of the catalytic unit and the catalytic conversion exhaust port are on the same side, and the gas separated and discharged through the catalytic conversion exhaust port is discharged. The lower layer of the catalytic unit and the catalytic conversion outlet 46 are on the same side to capture and eliminate the alkali liquid discharged through the catalytic conversion outlet 46. Capture and eliminate.

[0046] The baffle 43 is arranged on the side of the catalytic conversion discharge port 46 and the catalytic conversion exhaust port 45, extends toward the center of the sleeve 38, and is adapted to the width of the sleeve 38. The baffle 43 has filter holes for filtering the alkali solution. Preferably, in order to achieve the best gas-liquid separation effect at this stage, the oxygen free radical catalytic converter is horizontally assembled. After the gas-liquid mixture flows through the catalytic converter of the present invention, effective gas-liquid stratification can be achieved, thereby reducing the workload of the gas-liquid separator in the electrolytic hydrogen production system, reducing the volume of the gas-liquid separator and making the design compact.

[0047] There is a height of 3-5 mm between the upper and lower layers of the catalytic units 36, and a spacing of 5-7 mm between adjacent catalytic units to balance the pressure drop of gas-liquid changes during the treatment process.

[0048] The catalytic units, designated as the first, second, and third catalytic units along the gas-liquid flow direction, are designed to progressively process the oxygen free radicals accumulated by the anode reaction. The pore sizes of the three catalytic units gradually decrease along the gas-liquid flow direction. Upon contact with the small pores, bubbles coalesce and separate, then are expelled from the liquid, effectively preventing bubble clogging within the catalytic units.

[0049] The first catalytic unit includes an alkaline liquid catalytic coating (located at the bottom layer) equipped with a Pt / C catalyst and a porous titanium gas diffusion catalytic coating (located at the top layer) for preferentially decomposing , to prevent subsequent As the high temperature alkali solution volatilizes and decomposes Corrosion to metal pipes and sealing materials.

[0050] The second catalytic unit includes an alkaline liquid catalytic coating layer (located at the lower layer) carrying a Mn / C catalyst and a Pt / C catalyst, and a porous titanium gas diffusion catalytic coating layer (located at the upper layer) that has been subjected to surface sulfonation treatment. The surface sulfonation treatment process is to introduce Group, enhance electrostatic adsorption; the alkaline catalytic coating and porous titanium gas diffusion catalytic coating equipped with Pt / C catalyst are used to decompose the regeneration of the disproportionation reaction. .

[0051] The third catalytic unit includes a The alkaline catalytic coating (located at the bottom layer) and the porous gas diffusion catalytic coating (located at the top layer) are used to remove The pore size of the alkali solution and the gas catalytic coating is the smallest, which can eliminate the bubbles in the alkali solution to the greatest extent and prevent As the bubbles enter the downstream of the alkaline water electrolysis hydrogen production system, they are prevented from clogging the catalytic converter.

[0052] The pore size of the lower layer of the three catalytic units (called the alkali liquid catalytic unit) gradually decreases along the gas-liquid flow direction, preferably 100μm, 50μm and 10μm, and the pore size of the upper layer of the three catalytic units (called the gas catalytic unit) gradually decreases along the gas-liquid flow direction, preferably 80μm, 30μm and 5μm. The bubbles carried in the alkali liquid gather into large-particle bubbles after contacting the small pores, and then desorb and discharge from the liquid, effectively avoiding the problem of bubble blockage in the catalytic unit.

[0053] A spring clip is provided at the connection between the housing and the catalytic unit. When an abnormal pressure difference occurs during operation, the catalytic efficiency is attenuated, or the response capability to special working conditions is reduced, resulting in poor working efficiency of the catalytic converter, the operation and maintenance personnel can directly disassemble it from the outside.

[0054] The process of using the catalytic conversion module is as follows: S1: The electrolyzer is running, and the gas-liquid mixture (generated oxygen and circulating alkali solution) enters the catalytic conversion module from the anode side outlet; S2. Control the operation of one of the oxygen free radical catalytic converters and monitor the alkali solution flow rate at the outlet of the oxygen free radical catalytic converter through a flow meter. If the flow rate is lower than half of the circulating alkali solution demand of the electrolytic cell under the current operating conditions, control the rotary valve at the inlet of the branch to increase the flow rate of the gas-liquid mixture. When the operating conditions of the alkaline electrolytic cell fluctuate, causing the flow rate of the gas-liquid mixture to be unstable, and the flow meter detects that the content of a branch is too high, control the rotary valve at the inlet of the branch to reduce the flow rate, and open the solenoid valves at the outlets of all catalytic conversion branches to connect to the recovery tank for pressure release, that is, discharge the excess alkali solution into the recovery tank. After the system stabilizes, readjust the inlet rotary valve. S3, control one of the oxygen free radical catalytic converters to operate, by The concentration detector monitors the oxygen free radical content at the outlet. If the oxygen free radical exceeds the standard, the operation and maintenance mode is entered, and the operation is switched to another oxygen free radical catalytic converter. The solenoid valves at the outlet of the alkali tank and the inlet of the sewage system are opened, and alkali solution is introduced to backwash the oxygen free radical catalytic converter with excessive oxygen free radicals, and then the alkali solution is led to the sewage system; if If the concentration detector detects that the content of oxygen free radicals is still exceeding the standard, the corresponding branch solenoid valve will be closed and the catalyst will be replaced.

[0055] In another technical solution, catalytic conversion baffles 44 are provided on the inner wall of the shell 35 at the corresponding positions of the catalytic conversion exhaust port 45 and the catalytic conversion drain port 46. The catalytic conversion baffles 44 can block part of the catalytic conversion exhaust port 45 or part of the catalytic conversion drain port 46. A rotary valve is provided at one end of the sleeve 38 where the catalytic conversion feed port is opened. By controlling the rotation of the rotary valve, the sleeve 38 is driven to rotate, thereby controlling the flow area of the catalytic conversion exhaust port 45 or the catalytic conversion drain port 46.

[0056] The inner wall of the shell 35 is provided with at least two groups of catalytic conversion baffles 44 with phase angle distribution. The contact area between the catalytic conversion baffle 44 and the catalytic conversion liquid discharge port 46 and the catalytic conversion exhaust port 45 is changed by controlling the rotary valve, thereby changing the flow rate of the liquid and gas entering the catalytic coating. An angle is set between the central axis of the catalytic conversion baffle and the vertical axis of the sleeve to form a phase angle difference, preferably 30° to 45°, to adapt to the control of the gas and liquid flow rate after separation under the change of the flow rate of the gas-liquid mixture, and to strengthen the subsequent catalyst layer to capture and eliminate oxygen free radicals for impurities present in the alkali solution and gas. If no angle is set between the central axis of the catalytic conversion baffle and the vertical axis of the sleeve, the same angle is maintained, the baffle is placed horizontally, the exhaust port and the liquid discharge port of the baffle coincide with the sleeve, the exhaust and liquid discharge rates are reduced, and blockage may occur in severe cases, so a certain phase difference is set for the baffle and the sleeve.

[0057] In another technical solution, the rotary valve includes a valve core 40 and a sealing assembly 34. The valve core 40 is installed at one end of the catalytic conversion feed port 39 of the rotatable sleeve 38. A layer of sealing assembly 34 is provided between the valve core 40 and the sleeve 38 to prevent the alkali solution from splashing; the valve core 40 is connected to the servo motor 41 for driving the valve core 40 to rotate.

[0058] The sleeve is provided with at least two groups of catalytic conversion feed ports 39 with phase angle distribution, and the valve core 40 is provided with connecting holes 42 corresponding to different feed ports. Through the rotation of the sleeve 38, the sleeve catalytic conversion feed ports 39 with different phase angle distribution and the corresponding connecting holes with different phase angles on the valve core 40 are connected separately or simultaneously, which is used to preliminarily control the flow rate and speed of the gas-liquid mixture entering the sleeve.

[0059] When the electrolytic cell is running, a gas-liquid mixture composed of the gas generated at the electrode and the circulating alkali solution introduced into the electrolytic cell 1 is discharged from the outlet of the electrolytic cell 1, and the gas-liquid mixture enters the sleeve 38 from the feed port, and undergoes preliminary gas-liquid separation through the baffle 43 of the sleeve 38. After passing through the baffle 43, the preliminarily separated alkali solution moves along the holes of the baffle 43 and gradually settles and gathers below the sleeve 38, and is discharged through the drain port at the bottom of the sleeve 38, enters the bottom of the catalytic unit of the catalytic converter housing, flows through the lower layers of the first catalytic unit, the second catalytic unit and the third catalytic unit, and respectively processes the alkali solution present in the alkali solution. The gas, small-particle alkali solution and alkali mist separated in the sleeve baffle are discharged through the exhaust port at the top of the sleeve, enter the top of the catalytic unit of the catalytic converter housing, flow through the upper layers of the first catalytic unit, the second catalytic unit and the third catalytic unit, and respectively The alkali mist and droplets are captured and eliminated, and then flow out of the catalytic converter through the outlet 37 of the housing. The gravitational potential energy generated by the agglomerates of attached alkali mist and droplets merging in the pores causes them to fall to the flowing alkali solution, achieving gas-liquid stratification and effectively controlling the content of alkali solution impurities carried by the gas at the outlet.

[0060] The rotation of the rotary valve affects the effective cross-sectional area of the oxygen free radical catalytic converter feed port, thereby controlling the volumetric flow rate of the gas-liquid mixture entering, and thus adjusting the gas-liquid separation efficiency of the sleeve under varying operating conditions. During this adjustment process, the contact area between the sleeve's catalytic converter exhaust and catalytic converter liquid discharge ports and the catalytic converter baffle of the housing changes synchronously. This changes the flow rate of the initially separated gas and liquid, which flow through the exhaust and catalytic converter liquid discharge ports, respectively, into the catalytic converter unit of the housing. By varying the gas-liquid flow time, the catalytic conversion efficiency is improved while stabilizing the pipeline pressure drop.

[0061] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and implementation methods. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A high-efficiency, low-consumption, long-life alkali solution circulation system for producing hydrogen by alkaline water electrolysis, characterized in that: It includes a cathode side and an anode side, wherein both the cathode side and the anode side are provided with a gas-liquid separation module, an alkaline solution circulation module, an alkaline solution circulation heat exchanger and an alkaline solution filter, and the anode side also includes a catalytic conversion module; wherein, For the anode side, the anode side output end of the alkaline water electrolysis hydrogen production device is connected to the input end of the catalytic conversion module, the output end of the catalytic conversion module is connected to the input end of the gas-liquid separation module, the gas-liquid separation module performs gas-liquid separation on the catalyzed gas-liquid mixture, and the liquid output end of the gas-liquid separation module is connected to the electrolyzer of the alkaline water electrolysis hydrogen production system in sequence through the alkaline liquid circulation module, the alkaline liquid circulation heat exchanger and the alkaline liquid filter to form a closed-loop circulation system; On the cathode side, the cathode side output end of the alkaline water electrolysis hydrogen production device is connected to the input end of the gas-liquid separation module, and the liquid output end of the gas-liquid separation module is connected to the electrolyzer of the alkaline water electrolysis hydrogen production system through the alkaline liquid circulation module, the alkaline liquid circulation heat exchanger and the alkaline liquid filter in sequence to form a closed-loop circulation system; Corresponding alkali liquid control modules are respectively provided on the anode side and the cathode side, and the input ends of the gas-liquid separators on the anode side and the cathode side are respectively connected to the corresponding alkali liquid control modules, and the alkali liquid control module includes an alkali liquid circulation controller, a third solenoid valve and an alkali replenishing tank; the gas-liquid separator on the cathode side and the gas-liquid separator on the anode side are connected through a U-shaped tube, and the alkali liquid circulation controller starts the alkali replenishing tank according to the change signal of the height on both sides of the liquid column in the U-shaped tube, and controls the alkali liquid inflow into the cathode side alkali replenishing tank and the anode side alkali replenishing tank according to the height difference of the liquid column in the U-shaped tube, so as to keep the liquid level on both sides of the U-shaped tube consistent.

2. The high-efficiency, low-consumption, and long-life alkali solution circulation system for producing hydrogen by alkaline water electrolysis according to claim 1, characterized in that: The gas-liquid separation module includes a gas-liquid separator, and both the cathode side and the anode side of the alkaline water electrolysis hydrogen production device are provided with a self-adaptive gas-liquid separator; The gas-liquid separator includes a separation cylinder, a spiral plate, a mist capture screen and a reset device, wherein a gas-liquid separation feed port is provided on the side wall of the separation cylinder, a gas-liquid separation discharge port is provided at the bottom, and a gas-liquid separation exhaust port is provided on the top. The gas-liquid separation exhaust port is connected to the gas-liquid separation discharge port through an exhaust channel. The gas-liquid separation feed port is connected to the electrolyzer of the electrolytic hydrogen production device, and the gas-liquid separation discharge port is connected to the alkali liquid circulation device. The spiral plate is located at the place where the gas-liquid separation feed port enters the separation cylinder, and spirally surrounds the outside of the exhaust channel. A liquid collecting device is provided below the spiral plate, and the spiral plate is movably arranged outside the exhaust channel through the reset device.

3. The high-efficiency, low-consumption, long-life alkali solution circulation system for producing hydrogen by alkaline water electrolysis according to claim 2, characterized in that: The height between the top of the spiral plate and the top of the separation cylinder is H, which is calculated using the following formula: Where V is the volume flow rate of alkali solution at the gas-liquid separation feed port, H is the length of the separation device when the volume flow rate of alkali solution is V; M1 is the correction coefficient; Q is the heat generation of the electrolytic cell under the current load, unit is W; is the density of the alkali solution, in kg / m 3 ; is the specific heat capacity of alkali solution at constant pressure, in J / kg.K; is the temperature difference between the inlet and outlet of the electrolytic cell, in K; the reset device here is a spring, k is the elastic coefficient of the spring; g is the acceleration due to gravity, in N / kg.

4. The high-efficiency, low-consumption, and long-life alkali solution circulation system for producing hydrogen by alkaline water electrolysis according to claim 2, characterized in that: The input ends of the alkali liquid circulation pumps on the anode side and the cathode side are respectively connected to the corresponding alkali liquid control modules. For the anode side, the input end of the catalytic conversion module is also connected to the alkali liquid control module; the alkali liquid circulation module is an alkali liquid circulation pump; For the alkali solution circulation pump, the alkali solution circulation controller starts the alkali feeding tank to replenish alkali solution to the pipeline or controls the pipeline to discharge liquid to the alkali feeding tank according to the flow control of the alkali solution circulation pump.

5. The high-efficiency, low-consumption, long-life alkali solution circulation system for producing hydrogen by alkaline water electrolysis according to claim 1, characterized in that: The catalytic conversion module comprises a plurality of catalytic conversion branches arranged in parallel, each catalytic conversion branch being provided with an oxygen free radical catalytic converter; A rotary valve is set at the inlet of each catalytic conversion branch, and a solenoid valve is set at the outlet. Each oxygen free radical catalytic converter is correspondingly provided with a flow meter to monitor its flow. Concentration detector; The outlets of all catalytic conversion branches are also connected to the gas-liquid separator through solenoid valves, and the outlets are also connected to the alkali replenishment tank through solenoid valves. The inlets of all catalytic conversion branches are connected to the sewage system through solenoid valves, and the inlets are also connected to the electrolyzer through solenoid valves.

6. The high-efficiency, low-consumption, and long-life alkali solution circulation system for producing hydrogen by alkaline water electrolysis according to claim 5, characterized in that: The oxygen free radical catalytic converter includes a shell, a sleeve and a catalytic unit. The sleeve is coaxially sleeved in the shell. The sleeve and the shell are both horizontally arranged, and one end of the sleeve is fixed to one end of the shell provided with a catalytic conversion feed port. The catalytic conversion feed port is connected to the anode side outlet of the alkaline water electrolysis hydrogen production device. The side wall of the sleeve and the side wall of the shell are separated by a certain distance. The upper side of the side wall in the sleeve is provided with a catalytic conversion exhaust port, and the lower side of the side wall is provided with a catalytic conversion liquid discharge port. A number of baffles are staggered and arranged on the inner side wall of the sleeve. A number of catalytic units are also arranged in the shell along its length direction at the rear side of the sleeve. Each catalytic unit is divided into an upper layer and a lower layer, and the two are separated by a certain distance. The upper layer of the catalytic unit and the catalytic conversion exhaust port are on the same side, and the gas separated and discharged through the catalytic conversion exhaust port is subjected to the treatment. To capture and eliminate, the lower layer of the catalytic unit and the catalytic conversion outlet are on the same side, and the alkali solution discharged through the catalytic conversion outlet is Capture and eliminate.

7. The high-efficiency, low-consumption, long-life alkali solution circulation system for producing hydrogen by alkaline water electrolysis according to claim 6, characterized in that: The catalytic units are respectively a first catalytic unit, a second catalytic unit and a third catalytic unit along the gas-liquid flow direction; The first catalytic unit includes an alkaline liquid catalytic coating equipped with a Pt / C catalyst and a porous titanium gas diffusion catalytic coating for preferentially decomposing , to prevent subsequent As the high temperature alkali solution volatilizes and decomposes Corrosion to metal pipes and sealing materials; The second catalytic unit includes an alkaline liquid catalytic coating layer carrying a Mn / C catalyst and a Pt / C catalyst, and a porous titanium gas diffusion catalytic coating layer with a surface sulfonation treatment; The third catalytic unit includes a Alkaline liquid catalytic coating and porous gas diffusion catalytic coating.

8. The high-efficiency, low-consumption, and long-life alkali solution circulation system for producing hydrogen by alkaline water electrolysis according to claim 6, characterized in that: The inner wall of the shell is provided with catalytic conversion baffles at the corresponding positions of the catalytic conversion exhaust port and the catalytic conversion discharge port. The catalytic conversion baffles can block part of the catalytic conversion exhaust port or part of the catalytic conversion discharge port. The end of the sleeve where the catalytic conversion feed port is opened is provided with a rotary valve. By controlling the rotation of the rotary valve, the sleeve is driven to rotate, thereby controlling the flow area of the catalytic conversion exhaust port or the catalytic conversion discharge port.

9. The high-efficiency, low-consumption, and long-life alkali solution circulation system for producing hydrogen by alkaline water electrolysis according to claim 8, characterized in that: The rotary valve includes a valve core and a sealing assembly. The valve core is installed at one end of the catalytic conversion feed port of a rotatable sleeve. A layer of sealing assembly is provided between the valve core and the sleeve to prevent alkali liquid from splashing. The valve core is connected to a servo motor to drive the valve core to rotate.

10. According to any one of claims 5 to 9, the high-efficiency, low-consumption, and long-life alkaline solution circulation system for producing hydrogen by alkaline water electrolysis, the catalytic conversion module is used as follows: S1, the electrolyzer is running, and the gas-liquid mixture enters the catalytic conversion module from the anode side outlet; S2. Control the operation of one of the oxygen free radical catalytic converters and monitor the alkali solution flow rate at the outlet of the oxygen free radical catalytic converter through a flow meter. If the flow rate is lower than half of the circulating alkali solution demand of the electrolyzer under the current operating conditions, control the rotary valve at the inlet of the branch to increase the flow rate of the gas-liquid mixture. When the operating conditions of the alkaline electrolyzer fluctuate, causing unstable flow rate of the gas-liquid mixture, and the flow meter detects that the content of a branch is too high, control the rotary valve at the inlet of the branch to reduce the flow rate, open the solenoid valves at the outlets of all catalytic conversion branches, connect the recovery tank to release the pressure, and readjust the inlet rotary valve after the system stabilizes. S3, control one of the oxygen free radical catalytic converters to operate, by The concentration detector monitors the oxygen free radical content at the outlet. If the oxygen free radical exceeds the standard, the operation and maintenance mode is entered, and the operation is switched to another oxygen free radical catalytic converter. The solenoid valves at the outlet of the alkali tank and the inlet of the sewage system are opened, and alkali solution is introduced to backwash the oxygen free radical catalytic converter with excessive oxygen free radicals, and then the alkali solution is led to the sewage system; if If the concentration detector detects that the content of oxygen free radicals is still exceeding the standard, the corresponding branch solenoid valve will be closed and the catalyst will be replaced.

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