Cooling waterway for PEM water electrolysis hydrogen production and water drainage structure of steam-water separator

Abstract

The utility model discloses a cooling waterway for PEM water electrolysis hydrogen production and a water drainage structure of a steam-water separator. The cooling water path is composed of an external infusion pump, a liquid storage tank, a PEM electrolytic bath, a steam-water separator and an internal circulating water pump, the liquid storage tank is sequentially connected with the PEM electrolytic bath and the steam-water separator, and the steam-water separator is connected with the liquid storage tank; the pipeline between the steam-water separator and the liquid storage tank is also connected with an external infusion pump; the external infusion pump is connected with the water inlet; and the liquid storage tank is also sequentially connected with the internal circulating water pump and the PEM electrolytic bath through pipelines. According to the utility model, the problems of layout and overall space of the water storage tank and the steam-water separator are solved by adopting an automatic drainage mode; the problem that a drainage valve is tedious in calibration is solved in an automatic drainage mode.

Description

Technical Field

[0001] The utility model belongs to the field of hydrogen production by water electrolysis, relates to a water separator drainage structure, and specifically relates to a cooling water channel for hydrogen production by water electrolysis using a PEM and a water separator drainage structure. Background Art

[0002] Hydrogen production by water electrolysis involves the electrochemical decomposition of water molecules into hydrogen and oxygen under the influence of direct current, which are then separated at the cathode and anode, respectively. Currently, there are three main technical routes for hydrogen production by water electrolysis: alkaline electrolysis (AWE), proton exchange membrane (PEM) electrolysis, and solid oxide electrolysis (SOEC). PEM water electrolysis is the most promising and mainstream water electrolysis technology due to its high efficiency.

[0003] The hydrogen produced by electrolysis in the electrolytic cell contains a large amount of water vapor, which affects the hydrogen concentration. Therefore, a steam-water separator is added. The hydrogen containing water vapor condenses into water droplets after passing through the steam-water separator and accumulates at the bottom of the steam-water separator. When the accumulation reaches a certain amount, the water needs to be discharged, but at the same time, the discharge of the electrolyzed hydrogen must be avoided.

[0004] Existing small-scale hydrogen generators discharge condensate from the steam-water separator directly or through a controlled discharge valve. This has the disadvantage that the condensate from the steam-water separator cannot be recycled. Using a solenoid valve control method requires an additional controller and tedious calibration of the solenoid valve opening time to prevent hydrogen discharge. The solenoid valve control method also places high demands on the overall valve core material, and the solenoid valve structure makes the overall volume larger, resulting in low space utilization. Utility Model Content

[0005] The present invention overcomes these shortcomings by providing a water separator drainage structure for small-scale PEM water electrolysis hydrogen production. This design utilizes automatic drainage to improve the layout and overall space requirements of the water tank and water separator. Automatic drainage also alleviates the cumbersome calibration of the drain valve. A one-way valve between the water separator drainage line and the water tank effectively prevents backflow of pure water from the tank.

[0006] A cooling water circuit for PEM water electrolysis hydrogen production consists of an external liquid pump, a liquid storage tank, a PEM electrolyzer, a steam-water separator and an internal circulating water pump. The liquid storage tank is connected to the PEM electrolyzer and the steam-water separator in sequence, the steam-water separator is connected to the liquid storage tank, and the pipeline between the steam-water separator and the liquid storage tank is also connected to the external liquid pump, and the water inlet of the external liquid pump is connected; the liquid storage tank is also connected to the internal circulating water pump and the PEM electrolyzer through a pipeline.

[0007] Furthermore, the specific connection structure of the cooling water circuit of the above-mentioned PEM water electrolysis hydrogen production is as follows: the circulating water inlet of the liquid storage tank is connected to the anode outlet of the PEM electrolyzer, the cathode outlet of the PEM electrolyzer is connected to the mixed gas inlet of the steam-water separator through a pipeline, and the condensed water outlet of the steam-water separator is connected to the liquid replenishment inlet of the liquid storage tank; the external liquid pump is connected to the liquid replenishment inlet of the liquid storage tank through a pipeline; the circulating water outlet of the liquid storage tank is connected to the internal circulating water pump and the anode inlet of the PEM electrolyzer in sequence through a pipeline.

[0008] Furthermore, a one-way valve is provided on the pipeline connecting the condensed water outlet of the steam-water separator and the liquid replenishing inlet of the liquid storage tank.

[0009] A water-gas separator drainage structure for a cooling water channel of a PEM electrolysis water hydrogen production system is disclosed. A hollow air float is provided inside a water-gas separator body, and a drainage port is provided at the bottom of the water-gas separator body.

[0010] Furthermore, the top of the steam-water separator body is provided with a hydrogen outlet after drying and an hydrogen inlet after electrolysis.

[0011] Furthermore, the post-electrolysis liquid discharge port is connected to the one-way valve and the liquid storage tank in sequence.

[0012] Furthermore, the dried hydrogen outlet is connected to a hydrogen purification system and used after purification.

[0013] Compared with the prior art, the advantages of this utility model are:

[0014] 1. The utility model avoids the use of solenoid valves to control the water discharge, reduces the cumbersome calibration of small hydrogen generators and the number of parts, and simplifies the entire hydrogen production system and control logic.

[0015] 2. The utility model avoids the use of a solenoid valve drainage solution, reduces the battery valve component, reduces the design difficulty and overall cost of the gas-water separator, and improves the overall layout space utilization.

[0016] 3. The condensed water in the present invention is recycled, which improves the utilization rate of raw water. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural diagram of the cooling water circuit;

[0018] Figure 2 Schematic diagram of the structure of the steam-water separator.

[0019] The components in the figure are as follows: external liquid extraction pump 1, liquid storage tank 2, PEM electrolyzer 3, steam-water separator 4, one-way valve 5, internal circulating water pump 6, dried hydrogen outlet 7, hollow air float 8, drain port 9, and hydrogen inlet after electrolysis 10. DETAILED DESCRIPTION

[0020] The following is a clear and complete description of the technical solutions in the embodiments of the present invention, with reference to the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, and not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are also within the scope of protection of the present invention.

[0021] A cooling water circuit for PEM electrolysis of water to produce hydrogen, such as Figure 1 and Figure 2 As shown, in this embodiment, the cooling water circuit consists of an external liquid pump 1, a liquid storage tank 2, a PEM electrolyzer 3, a water separator 4, and an internal circulating water pump 6. The circulating water inlet of the liquid storage tank 2 is connected to the anode outlet of the PEM electrolyzer 3. The cathode outlet of the PEM electrolyzer 3 is connected to the mixed gas inlet of the water separator 4 via a pipeline. The condensed water outlet of the water separator 4 is connected to the rehydration inlet of the liquid storage tank 2. The external liquid pump 1 is connected to the rehydration inlet of the liquid storage tank 2 via a pipeline. The circulating water outlet of the liquid storage tank 2 is connected to the internal circulating water pump 6 and the anode inlet of the PEM electrolyzer 3, respectively, via pipelines. A one-way valve 5 is installed on the pipeline connecting the condensed water outlet of the water separator 4 to the rehydration inlet of the liquid storage tank 2. This one-way valve 5 ensures that the external liquid pump 1 can only pump pure water into the water storage tank, but not into the bottom of the water separator.

[0022] like Figure 2 As shown, in this embodiment, a hollow air float 8 is installed inside the separator body. A drain port 9 is provided at the bottom of the separator body. A dried hydrogen outlet 7 and an electrolyzed hydrogen inlet 10 are provided at the top of the separator body. The condensed water outlet 9 is connected to a one-way valve 5 and a liquid storage tank 2 in sequence. The dried hydrogen outlet 7 is connected to a purification system.

[0023] The overall working principle of this embodiment is:

[0024] In the initial state of steam-water separation, the float is at the bottom of the steam-water separator, completely covering the drain port of the steam-water separator. When PEM electrolysis produces hydrogen, the hydrogen containing water vapor produced by electrolysis enters the steam-water separator. Due to the increase in space and the decrease in temperature, the water vapor condenses into droplets and accumulates at the bottom of the steam-water separator. When the water accumulates to a certain amount, the buoyancy of the water is greater than the gravity of the air float, the air float rises, and the drain port opens. However, at this time, the liquid does not flow to the water tank. When the liquid squeezes the air in the tube and reaches the opening pressure of the one-way valve (opening pressure is 3~10kPa), the one-way valve opens. At this time, the water tank is connected to the bottom of the steam-water separator, and the liquid levels of the two will be consistent. Therefore, when the liquid level accumulated at the bottom of the steam-water separator is higher than the liquid level of the water tank, the liquid will flow to the water tank side, thereby achieving balance again.

[0025] During the overall PEM electrolysis hydrogen production and water addition process, due to the action of the one-way valve 5, the external liquid pump can only pump pure water into the water storage tank, but cannot pump it into the bottom of the steam-water separator.

[0026] The above is only an embodiment of the present invention, and common knowledge such as the specific structure and characteristics of the scheme are not described in detail here. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the appended claims rather than the above description, and it is intended that all changes that fall within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claim involved.

Claims

1. A cooling water circuit for PEM water electrolysis hydrogen production, characterized in that: The invention comprises an external liquid pump (1), a liquid storage tank (2), a PEM electrolyzer (3), a steam-water separator (4) and an internal circulating water pump (6); the liquid storage tank (2) is connected to the PEM electrolyzer (3) and the steam-water separator (4) in sequence, and the steam-water separator (4) is connected to the liquid storage tank (2); the external liquid pump (1) is also connected to the pipeline between the steam-water separator (4) and the liquid storage tank (2), and the external liquid pump (1) is connected to the water inlet; the liquid storage tank (2) is also connected to the internal circulating water pump (6) and the PEM electrolyzer (3) in sequence through the pipeline.

2. The cooling water circuit of a PEM electrolysis hydrogen production system according to claim 1, characterized in that: The specific connection structure is as follows: the circulating water inlet of the liquid storage tank (2) is connected to the anode outlet of the PEM electrolyzer (3); the cathode outlet of the PEM electrolyzer (3) is connected to the mixed gas inlet of the steam-water separator (4) through a pipeline; the condensed water outlet of the steam-water separator (4) is connected to the liquid replenishment inlet of the liquid storage tank (2); the external liquid pump (1) is connected to the liquid replenishment inlet of the liquid storage tank (2) through a pipeline; the circulating water outlet of the liquid storage tank (2) is connected to the internal circulating water pump (6) and the anode inlet of the PEM electrolyzer (3) in sequence through a pipeline.

3. A cooling water circuit for hydrogen production by PEM electrolysis of water according to claim 1 or 2, characterized in that: A one-way valve (5) is provided on the pipeline connecting the condensed water outlet of the steam-water separator (4) and the liquid replenishing inlet of the liquid storage tank (2).

4. A steam-water separator drainage structure for a cooling water circuit of a PEM water electrolysis hydrogen production system according to any one of claims 1 to 3, characterized in that: A hollow air float (8) is provided inside the steam-water separator body, and a liquid discharge port (9) is provided at the bottom of the steam-water separator body.

5. The steam-water separator drainage structure according to claim 4, characterized in that: The top of the steam-water separator body is provided with a dried hydrogen outlet (7) and a post-electrolysis hydrogen inlet (10).

6. The steam-water separator drainage structure according to claim 5, characterized in that: The post-electrolysis liquid discharge port (9) is connected to the one-way valve (5) and the liquid storage tank (2) in sequence.

7. The steam-water separator drainage structure according to claim 5, characterized in that: The dried hydrogen outlet (7) is connected to a hydrogen purification system and is used after purification.

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