WO2025097294A1 - Apparatus for producing hydrogen from alkaline water and system for producing hydrogen - Google Patents

Abstract

Disclosed in the present application are an apparatus for producing hydrogen from alkaline water and a system for producing hydrogen. The apparatus for producing hydrogen comprises an alkaline-water electrolytic cell, wherein a plurality of electrode plates are inserted into the alkaline-water electrolytic cell, and the plurality of electrode plates are sequentially arranged at set intervals; when the electrode plates are powered on, the plurality of electrode plates are arranged in a manner that an anode and a cathode face each other; and at least some of the plurality of electrode plates are each provided with an elastic assembly. In the present application, an elastic assembly is provided in an electrode plate to push the anode to the cathode as much as possible, thereby reducing the voltage of a unit cell; in addition, during process control, a gas-phase pressure on the anode side is maintained higher than that on the cathode side, such that the purity of a gas generated by means of an electrolytic reaction is reduced, and the safety of the electrolytic cell and process for producing hydrogen from alkaline water is improved.

Description

Alkaline water hydrogen production equipment and hydrogen production system Technical Field

The present application relates to alkaline water hydrogen production equipment, and in particular to an alkaline water hydrogen production equipment and a hydrogen production system.

Background Art

In alkaline water electrolysis, water is electrolyzed using alkaline solution as an electrolyte, with hydrogen generated on the cathode side and oxygen generated on the anode side. A diaphragm is provided between the cathode side and the anode side. The diaphragm can isolate the gases generated by the cathode and anode and allow the electrolyte to flow. In the cost of hydrogen production by alkaline water electrolysis, electricity costs account for more than 70% of the total cost, and the DC energy consumption of the core electrolysis equipment accounts for more than 80% or even 90% of the electricity cost. Therefore, to improve the energy efficiency value of the equipment, it is necessary to reduce the unit cell voltage.

At present, although alkaline water hydrogen production equipment has some technical means to reduce the unit cell voltage, it cannot meet the ideal industrial demand for hydrogen production.

Summary of the invention

In view of the above problems, the present application provides an alkaline water hydrogen production equipment and a hydrogen production system, which can at least solve the aforementioned technical problems.

According to the first aspect of the present application, there is provided an alkaline water hydrogen production device, comprising:

An alkaline water electrolysis cell is provided with a plurality of electrode plates, wherein the plurality of electrode plates are arranged in sequence at set intervals; when the electrode plates are powered on, the plurality of electrode plates are arranged in a manner that anodes and cathodes face each other;

At least a portion of the plurality of electrode plates is installed with an elastic component.

In some optional embodiments, during the electrolysis process, the gas phase pressure of the anode electrode plate among the plurality of electrode plates is made higher than the gas phase pressure of the cathode electrode plate.

In some optional embodiments, at least a portion of the plurality of electrode plates is installed with an elastic component, including:

The elastic component is mounted on the anode electrode plate.

In some optional embodiments, the plurality of electrode plates are structures of anode film spacing.

In some optional embodiments, the thickness of the elastic components installed on different anode electrode plates is different.

In some optional embodiments, at least a portion of the plurality of electrode plates is installed with an elastic component, including:

The elastic component is mounted on the cathode electrode plate.

In some optional embodiments, the plurality of electrode plates are a cathode film pole pitch structure.

In some optional embodiments, the device further comprises:

The electrolyte storage tank is connected to the alkaline water electrolysis tank and automatically replenishes the electrolyzed alkaline water in the alkaline water electrolysis tank.

In some optional embodiments, the alkaline water electrolysis cell is also provided with valve instruments for controlling temperature, pressure and flow respectively. The electrolysis state of the alkaline water electrolysis cell can be obtained through the valve instruments, and the temperature, pressure and flow of the electrolyte can be conveniently controlled based on the electrolysis state.

According to a second aspect of the present application, a hydrogen production system is provided, the system comprising the alkaline water hydrogen production equipment.

The technical solution of the embodiment of the present application is to adjust the overall voltage of hydrogen production of the alkaline water hydrogen production equipment by improving the membrane distance between the electrode plates in the alkaline water hydrogen production equipment to achieve the purpose of energy saving. The embodiment of the present application sets an elastic component in the electrode plate to push the anode electrode toward the cathode as much as possible to reduce the unit cell voltage, and at the same time, in the process control, keep the gas phase pressure on the anode side greater than the gas phase pressure on the cathode side, so that the purity of the gas generated by the electrolysis reaction is reduced, and at the same time, the safety of the alkaline water hydrogen production electrolyzer and process is improved.

The above description is only an overview of the technical solution of this application. Technical means can be implemented according to the contents of the specification, and in order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below.

BRIEF DESCRIPTION OF THE DRAWINGS

Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

FIG1 shows a schematic structural diagram of an alkaline water hydrogen production device provided in an embodiment of the present application.

DETAILED DESCRIPTION

The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

FIG. 1 shows a schematic diagram of the structure of an alkaline water hydrogen production device provided in an embodiment of the present application, as shown in FIG. 1 As shown, the alkaline water hydrogen production equipment of the embodiment of the present application includes an alkaline water electrolyzer, which includes at least one anode plate and at least one cathode plate, and the anode plate and the cathode plate are connected to a power supply to electrolyze the alkaline water electrolyte. An oxygen regulating valve is provided on the anode plate side to adjust the pressure on the anode side. The electrolytic oxygen of the anode plate is processed by the oxygen processing unit and output to the oxygen purity analysis module for purity analysis, and output to the corresponding oxygen collection bin. A hydrogen regulating valve is provided on the cathode plate side to adjust the pressure on the cathode side. The electrolytic hydrogen on the cathode plate side is processed by the hydrogen processing unit and output to the hydrogen purity analysis module for purity analysis, and output to the corresponding hydrogen collection bin.

In the embodiment of the present application, among the main factors constituting the unit cell voltage, the theoretical decomposition voltage of electrolysis, the voltage drop of the loop metal conductor, the ohmic voltage drop on the anode and cathode sides, the voltage drop of the diaphragm, and the overpotential of the oxygen and hydrogen evolution electrode used are included. Among the main factors affecting the cell voltage, one is the structural factors of the electrolyzer, including the structural design of the electrolyzer, the arrangement and inter-electrode spacing of the electrodes, the conductivity of the conductor, the surface resistance of the diaphragm, and the structure and performance of the anode and cathode electrodes. The second is the operating factors, including the pressure and pressure difference control in the electrolyzer, the circulation amount of the electrolyte, the concentration and temperature of the electrolyte.

Combining the structural factors and operational factors that affect the cell voltage, an effective method is to use a zero-pole distance structure in the alkaline water electrolyzer to bring the cathode and anode as close as possible to reduce the cell voltage. In the chlor-alkali electrolyzer, by using elastic components, the anode electrode is pushed as close to the cathode as possible, and at the same time, in process control, the gas phase pressure on the anode side is kept greater than the gas phase pressure on the cathode side.

In an alkaline water electrolyzer, if the high-pressure structure of the electrolyzer is directly translated and applied to the alkaline water electrolyzer, hydrogen will accumulate in the oxygen on the anode side due to the micro-permeability of the membrane, causing the hydrogen in the oxygen to exceed the explosion limit and causing a safety accident.

The problem to be solved by the embodiments of the present application is to reduce the cell voltage of the unit cell while maintaining a zero-pole gap structure, and not reduce the purity of the gas produced by the electrolysis reaction, while improving the safety of the alkaline water hydrogen production electrolysis cell and process.

As shown in FIG1 , the alkaline water hydrogen production equipment of the embodiment of the present application comprises:

An alkaline water electrolysis cell is provided with a plurality of electrode plates, wherein the plurality of electrode plates are arranged in sequence at set intervals; when the electrode plates are powered on, the plurality of electrode plates are arranged in a manner such that anodes and cathodes are opposite to each other; in the embodiment of the present application, although only one group of electrode plates is shown in FIG1 , as an implementation method, a plurality of electrode plate groups may be provided.

At least a portion of the multiple electrode plates are installed with elastic components. In the embodiment of the present application, by arranging the elastic components in the electrode plates, the spacing between the anode and cathode in the electrode plates can be made closer, thereby reducing the voltage between the anode and cathode.

In the embodiment of the present application, during the electrolysis process, the gas phase pressure of the anode electrode plate among the plurality of electrode plates is made higher than the gas phase pressure of the cathode electrode plate. As an implementation method, the gas phase pressure on the anode plate side is controlled to be greater than the pressure on the cathode plate side. For example, the pressure difference can be maintained at about 100 mm water column, so that the diaphragm is as close to the cathode electrode as possible, so that the hydrogen content in oxygen can be reduced and the purity of hydrogen can be ensured.

In the embodiment of the present application, the elastic component can be installed on the anode electrode plate. Of course, as an implementation method, the elastic component can also be installed on the cathode electrode plate.

In the embodiment of the present application, the multiple electrode plates are of a cathode membrane spacing structure, that is, the alkaline water electrolyzer of the embodiment of the present application can adopt the cathode membrane spacing method.

In the embodiment of the present application, the thickness of the elastic components installed on different anode electrode plates is different, so as to adjust the electrolysis voltage according to the spacing distance between the anode electrode plate and the cathode electrode plate.

In some optional embodiments, the plurality of electrode plates are of an anode membrane spacing structure, that is, the alkaline water electrolyzer of the embodiment of the present application may also adopt an anode membrane spacing method.

In the embodiment of the present application, the device further includes:

The electrolyte storage tank is connected to the alkaline water electrolysis tank and automatically replenishes the electrolyzed alkaline water in the alkaline water electrolysis tank.

In some optional embodiments, the alkaline water electrolysis cell is further provided with valve instruments for controlling temperature, pressure and flow respectively, and the electrolysis state of the alkaline water electrolysis cell can be obtained through the valve instruments. The temperature, pressure and flow rate of the electrolyte can be conveniently controlled based on the electrolysis state.

According to the technical scheme of the embodiment of the present application, several schemes of membrane pole distance structure and its electrode and process control method are proposed. First, the alkaline water electrolyzer adopts the scheme of cathode membrane pole distance, and the elastic component is installed on the cathode. During the process operation, the gas phase pressure of the anode is controlled to be slightly higher than the gas phase pressure of the cathode; second, the anode and cathode of the alkaline water electrolyzer both adopt elastic structures, and are equipped with elastic components of different thicknesses, and the gas phase pressure of the anode is controlled to be slightly higher than the gas phase pressure of the cathode; third, the alkaline water electrolyzer adopts the structure of anode membrane pole distance, and the gas phase pressure of the anode is controlled to be higher than the gas phase pressure of the cathode. In each scheme, different electrode schemes are used to select a scheme that can ensure the purity of hydrogen, keep the hydrogen in the oxygen on the anode side within a safe range, and ensure that the cell voltage is low. The specific implementation plan and results are shown in Table 1 below.

Table 1

In the examples of the present application, in Table 1, all schemes select organic-inorganic composite membranes.

In the technical scheme of the embodiment of the present application, through the scheme parameter comparison in Table 1 and various test comparisons designed by the inventor, a scheme and process control method that can improve the safety of hydrogen production in an alkaline water electrolysis cell and reduce the voltage of a unit cell is: using a unit cell with anodes and cathodes back to back, the cathode of the unit cell adopts a mesh form, an elastic structure is installed on the anode side, and an electrode formula of formula W is adopted, and at the same time, the gas phase pressure on the anode plate side is controlled to be greater than that on the cathode plate side, and the pressure difference is about 100mm The water column makes the diaphragm as close to the cathode electrode as possible. This solution can not only reduce the hydrogen content in oxygen, but also ensure the purity of hydrogen, and at the same time obtain a lower unit cell voltage. Although the technical solution of the embodiment of the present application is only described as an example of a better technical solution, the other technical solutions in Table 1 are also technical solutions that can be adopted, and they can also be used as candidate technical solutions for adoption, which are also part of the technical solution of the embodiment of the present application.

The embodiment of the present application also describes a hydrogen production system, which includes the alkaline water hydrogen production equipment of the above embodiment.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims (10)

An alkaline water hydrogen production device, characterized in that the device comprises: An alkaline water electrolysis cell is provided with a plurality of electrode plates, wherein the plurality of electrode plates are arranged in sequence at set intervals; when the electrode plates are powered on, the plurality of electrode plates are arranged in a manner that anodes and cathodes face each other; At least a portion of the plurality of electrode plates is installed with an elastic component. The alkaline water hydrogen production equipment according to claim 1 is characterized in that, during the electrolysis process, the gas phase pressure of the anode electrode plate among the multiple electrode plates is made higher than the gas phase pressure of the cathode electrode plate. The alkaline water hydrogen production equipment according to claim 1 is characterized in that at least a portion of the plurality of electrode plates are installed with elastic components, including: The elastic component is mounted on the anode electrode plate. The alkaline water hydrogen production equipment according to claim 3 is characterized in that the multiple electrode plates are anode membrane pole spacing structures. The alkaline water hydrogen production equipment according to claim 4 is characterized in that the thickness of the elastic components installed on different anode electrode plates is different. The alkaline water hydrogen production equipment according to claim 1 is characterized in that at least a portion of the plurality of electrode plates are installed with elastic components, including: The elastic component is mounted on the cathode electrode plate. The alkaline water hydrogen production equipment according to claim 6 is characterized in that the multiple electrode plates are a cathode membrane pole distance structure. The alkaline water hydrogen production equipment according to any one of claims 1 to 7, characterized in that the equipment also includes: The electrolyte storage tank is connected to the alkaline water electrolysis tank and automatically replenishes the electrolyzed alkaline water in the alkaline water electrolysis tank. The alkaline water hydrogen production equipment according to claim 8 is characterized in that the alkaline water electrolyzer is also provided with valve instruments for respectively controlling temperature, pressure and flow, and the electrolysis state of the alkaline water electrolyzer can be obtained through the valve instrument, and the temperature, pressure and flow of the electrolyte can be conveniently controlled based on the electrolysis state. A hydrogen production system, characterized in that the system comprises the alkaline water hydrogen production equipment according to any one of claims 1 to 9.