Compressed air supply device for an alkaline hydrogen production system

Abstract

The application discloses a compressed air supply device in an alkaline hydrogen production system and relates to the technical field of alkaline hydrogen production.The compressed air supply device is connected with a separation system, a purification system and other auxiliary systems, one end of the compressed air supply device and the separation system is fixedly connected with a branch oxygen pipeline through a pipeline, one end of the branch oxygen pipeline is fixedly connected with a throttle valve through a pipeline, one end of the throttle valve is fixedly connected with a pressure reducing valve through a pipeline, one end of the pressure reducing valve is fixedly connected with an electric ball valve one through a pipeline, one end of a pressure sensor is fixedly connected to the pipeline between the pressure reducing valve and the electric ball valve one, and one end of the electric ball valve one is fixedly connected with an electric ball valve two through a pipeline; the oxygen discharged from the separation system is used to replace the compressed air produced by the air compressor to supply the pneumatic elements in each system with air, so that the air compressor can be closed and stopped working, and the starting rate of the air compressor in the whole hydrogen production system can be effectively reduced, thereby reducing the power consumption.

Description

Technical Field

[0001] This invention relates to the field of alkaline hydrogen production technology, and more particularly to a compressed air supply device in an alkaline hydrogen production system. Background Technology

[0002] Hydrogen production is a sustainable energy solution and is widely considered an important future direction for the energy industry. Hydrogen production equipment is one of the main devices for producing hydrogen and also a major energy-consuming device; however, the power consumption in the hydrogen production process has always been a key issue restricting its practical application. Hydrogen production technologies include various methods such as water electrolysis, chemical reaction, and biological methods. Among these, water electrolysis is one of the most commonly used methods. Alkaline water electrolysis is relatively mature in this method, where water molecules are decomposed into hydrogen and oxygen, requiring electricity. The entire hydrogen production system consists of an electrolyzer, a separation system, a purification system, and auxiliary systems. The power consumption of a water electrolysis hydrogen production system is related to the electrolysis equipment and process conditions used. Currently, methods such as improving electrode materials and electrolytes, and optimizing electrolysis reaction conditions, while improving energy consumption, also increase production costs, hindering marketization.

[0003] A search revealed Chinese patent publication number CN117684185A, which discloses an alkaline water electrolysis hydrogen production device and method, including: an electrolyzer, a hydrogen separator, an oxygen separator, a heat exchanger, and a deoxygenation reactor. While this patent can extend the lifespan of the deoxygenation catalyst and reduce energy consumption by lowering the relative humidity of the hydrogen, it lacks a method to reduce the power consumption of the compressed air supply device in the hydrogen production unit, further reducing power consumption during hydrogen production. Additionally, the overall device suffers from insufficient utilization of the discharged oxygen. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a compressed air supply device for an alkaline hydrogen production system.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A compressed air supply device for an alkaline hydrogen production system includes a compressed air supply system connected to a separation system, a purification system, and other auxiliary systems. One end of the compressed air supply system and the separation system is fixedly connected to a branch oxygen pipeline via a pipe. One end of the branch oxygen pipeline is fixedly connected to a throttle valve via a pipe. One end of the throttle valve is fixedly connected to a pressure reducing valve via a pipe. One end of the pressure reducing valve is fixedly connected to an electric ball valve one via a pipe. One end of the pressure reducing valve is fixedly connected to a pipe between the pressure reducing valve and the electric ball valve one. One end of the electric ball valve one is fixedly connected to an electric ball valve two via a pipe. One end of the electric ball valve two is fixedly connected to a pressure gauge via a pipe.

[0007] Preferably, the compressed air supply system includes a filter, an air compressor, and a control cabinet. One end of the air compressor is fixedly connected to the filter via a pipe, and the other end of the air compressor is fixedly connected to an electric ball valve and a pressure gauge via a pipe. One end of the control cabinet is fixedly connected to the electric ball valve via a pipe. The control cabinet is used to control the operation of pneumatic components in each system.

[0008] Furthermore: the separation system includes an oxygen-alkali solution separator, an oxygen scrubber, an oxygen cooler, an oxygen-liquid separator, and a diaphragm valve. One end of the oxygen-alkali solution separator is used to introduce oxygen and alkali solution, and the other end of the oxygen-alkali solution separator is fixedly connected to the oxygen scrubber through a pipeline. One end of the oxygen scrubber is fixedly connected to the oxygen cooler through a pipeline, and one end of the oxygen cooler is fixedly connected to the oxygen-liquid separator through a pipeline. One end of the oxygen-liquid separator is fixedly connected to the diaphragm valve through a pipeline. One end of the branch oxygen pipeline is fixedly connected to the pipeline between the oxygen-liquid separator and the diaphragm valve, and the oxygen is discharged through one end of the diaphragm valve.

[0009] Furthermore, the separation system also includes a hydrogen-alkali solution separator, a hydrogen scrubber, a hydrogen cooler, and a hydrogen-liquid separator. One end of the hydrogen-alkali solution separator is supplied with hydrogen gas and alkali solution. One end of the hydrogen scrubber is fixedly connected to one end of the hydrogen-alkali solution separator via a pipe. One end of the hydrogen cooler is fixedly connected to the hydrogen scrubber via a pipe. One end of the hydrogen-liquid separator is fixedly connected to the hydrogen cooler via a pipe.

[0010] The working process of a compressed air supply device in an alkaline hydrogen production system is as follows: when the hydrogen production system starts working, the air compressor in the compressed air supply system starts working, and at the same time, electric ball valve two opens and electric ball valve one closes to supply air to the control cabinet.

[0011] As a further aspect of the present invention: when the readings of the pressure sensor and the pressure gauge reach a certain value, the air compressor in the compressed air supply system stops, and at the same time, the electric ball valve two is closed and the electric ball valve one is opened. At this time, oxygen replaces compressed air to supply air to the control cabinet in the compressed air supply system.

[0012] As a further aspect of the present invention: the pressure reducing valve reduces the oxygen pressure in the branch oxygen pipeline to 0.4 MPa.

[0013] Based on the aforementioned solution: the throttle valve reduces the oxygen flow rate entering the branch oxygen pipeline to 3.5m. 3 / h.

[0014] Based on the aforementioned scheme: the oxygen discharged from one end of the oxygen-liquid separator has an oxygen pressure of 3.2 MPa and a temperature of 65-85 degrees Celsius.

[0015] The beneficial effects of this invention are as follows:

[0016] 1. A compressed air supply device in an alkaline hydrogen production system, which uses oxygen discharged from the separation system to replace the compressed air generated by the air compressor to supply air to the pneumatic components in each system. This allows the air compressor to be shut down and stop working, effectively reducing the operating rate of the air compressor in the entire hydrogen production system and reducing power consumption.

[0017] 2. A compressed air supply device in an alkaline hydrogen production system, which is modified by adopting pipelines and adding pressure reducing valves and throttling valves, has a relatively low modification cost for the entire hydrogen production system and is more conducive to construction and market promotion.

[0018] 3. A compressed air supply device in an alkaline hydrogen production system, which improves oxygen utilization by optimizing the process routes of the hydrogen production unit's separation system and compressed air supply system.

[0019] 4. A compressed air supply device in an alkaline hydrogen production system, which compares the values ​​between a pressure sensor and a pressure gauge to determine whether to open or close electric ball valve one and electric ball valve two, thereby automatically shutting down the air compressor and simplifying the operation process. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the compression control supply device structure of a compressed air supply device in an alkaline hydrogen production system proposed in this invention.

[0021] Figure 2 This is a schematic diagram of the separation system structure of the compressed air supply device in an alkaline hydrogen production system proposed in this invention.

[0022] In the diagram: 1. Branch oxygen pipeline; 2. Throttling valve; 3. Pressure reducing valve; 4. Pressure sensor; 5. Electric ball valve one; 6. Electric ball valve two; 7. Pressure gauge; 8. Oxygen-alkali separator; 9. Hydrogen-alkali separator; 10. Oxygen scrubber; 11. Hydrogen scrubber; 12. Oxygen cooler; 13. Hydrogen cooler; 14. Oxygen-liquid separator; 15. Hydrogen-liquid separator; 16. Diaphragm valve; 17. Filter; 18. Air compressor; 19. Control cabinet. Detailed Implementation

[0023] The technical solution of this patent will be further described in detail below with reference to specific embodiments.

[0024] The embodiments of this patent are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this patent, and should not be construed as limiting this patent.

[0025] Example 1:

[0026] A compressed air supply device in an alkaline hydrogen production system, such as Figure 1-2 As shown, a compressed air supply system includes a separation system, a purification system, and other auxiliary systems. One end of the compressed air supply system and the separation system is fixedly connected to a branch oxygen pipeline 1 via a pipe. One end of the branch oxygen pipeline 1 is fixedly connected to a throttle valve 2 via a pipe. One end of the throttle valve 2 is fixedly connected to a pressure reducing valve 3 via a pipe. One end of the pressure reducing valve 3 is fixedly connected to an electric ball valve 5 via a pipe. One end of the pressure sensor 4 is fixedly connected to the pipe between the pressure reducing valve 3 and the electric ball valve 5. One end of the electric ball valve 5 is fixedly connected to an electric ball valve 6 via a pipe. One end of the electric ball valve 6 is fixedly connected to a pressure gauge 7 via a pipe.

[0027] The compressed air supply system includes a filter 17, an air compressor 18, and a control cabinet 19. One end of the air compressor 18 is fixedly connected to the filter 17 via a pipe, and the other end of the air compressor 18 is fixedly connected to the electric ball valve 6 and the pressure gauge 7 via a pipe. One end of the control cabinet 19 is fixedly connected to the electric ball valve 6 via a pipe. The control cabinet 19 is used to control the operation of the pneumatic components in each system.

[0028] The separation system includes an oxygen-alkali separator 8, an oxygen scrubber 10, an oxygen cooler 12, an oxygen-liquid separator 14, and a diaphragm valve 16. One end of the oxygen-alkali separator 8 is used to introduce oxygen and alkali solution, and the other end of the oxygen-alkali separator 8 is fixedly connected to the oxygen scrubber 10 through a pipeline. One end of the oxygen scrubber 10 is fixedly connected to the oxygen cooler 12 through a pipeline, and one end of the oxygen cooler 12 is fixedly connected to the oxygen-liquid separator 14 through a pipeline. One end of the oxygen-liquid separator 14 is fixedly connected to the diaphragm valve 16 through a pipeline. One end of the branch oxygen pipeline 1 is fixedly connected to the pipeline between the oxygen-liquid separator 14 and the diaphragm valve 16, and the oxygen is discharged through one end of the diaphragm valve 16.

[0029] Oxygen and alkali solution enter the oxygen-alkali solution separator 8 for separation, then enter the oxygen scrubber 10 for washing, and then enter the oxygen cooler 12 for cooling. After the water is separated by the oxygen-water separator 14, it can be discharged through the diaphragm valve 16.

[0030] One end of the branch oxygen pipeline 1 is installed on the pipeline between the oxygen-liquid separator 14 and the diaphragm valve 16. The oxygen discharged from one end of the oxygen-liquid separator 14 has a pressure of 3.2 MPa and a temperature of 65-85 degrees Celsius. The dry oxygen discharged from one end of the oxygen-liquid separator 14 can be introduced into the compressed air supply system to replace the compressed air for use. This can effectively reduce the power consumption of the compressed air supply device in the auxiliary device of the hydrogen production unit. By reducing the power consumption of the auxiliary device, the total power consumption in the entire hydrogen production process is reduced.

[0031] Meanwhile, pressure gauge 7 and electric ball valve 6 are installed on the pipeline after air compressor 18 in the compressed air supply system. The air pressure at the outlet of air compressor 18 is 0.4MPa and the flow rate is 3.5m3 / h. The air flow rate and pressure discharged from one end of oxygen-liquid separator 14 are greater than the air flow rate and pressure in the compressed air supply system. Therefore, throttle valve 2 needs to be installed to make the oxygen flow rate in branch oxygen pipeline 1 consistent with the compressed air flow rate in the compressed air supply system. Pressure reducing valve 3 can make the pressure in branch oxygen pipeline 1 consistent with the output pressure of compressed air supply system to 0.4MPa. And by comparing the values ​​between pressure sensor 4 and pressure gauge 7, it is used to determine whether to open electric ball valve 5 and electric ball valve 6.

[0032] When the entire hydrogen production system starts working, the air compressor 18 in the compressed air supply system starts working. At the same time, the electric ball valve 6 opens and the electric ball valve 5 closes, supplying compressed air with a certain flow and pressure to the control cabinet 19 in the compressed air supply system. The control cabinet 19 then distributes the compressed air to the corresponding valves in the gas system.

[0033] When oxygen is generated on the oxygen side of the hydrogen production system and enters the branch oxygen pipeline 1 through one end of the oxygen-liquid separator 14, the pressure sensor 4 will display the pressure. When the throttle valve 2 works to make the value of the pressure sensor 4 consistent with the value of the pressure gauge 7, the air compressor 18 in the compressed air supply system stops, and at the same time, the electric ball valve 2 6 is closed and the electric ball valve 1 5 is opened. At this time, oxygen replaces compressed air and enters the control cabinet 19 of the compressed air supply system to supply air to the pneumatic components in each system.

[0034] By shutting down the air compressor 18 and using the oxygen discharged from the separation system to replace the compressed air produced by the air compressor 18 to supply air to the pneumatic components in each system, the operating rate of the air compressor in the entire hydrogen production system can be effectively reduced, thus reducing power consumption. At the same time, the utilization rate of oxygen is also improved, and the modification cost of the entire hydrogen production system is relatively low, providing more possibilities for the energy utilization of the hydrogen production system.

[0035] To solve the problem of hydrogen separation and washing; such as Figure 1-2 As shown, the separation system also includes a hydrogen-alkali separator 9, a hydrogen scrubber 11, a hydrogen cooler 13, and a hydrogen-liquid separator 15. One end of the hydrogen-alkali separator 9 is fed with hydrogen and alkali solution, and one end of the hydrogen scrubber 11 is fixedly connected to one end of the hydrogen-alkali separator 9 via a pipeline. In alkaline hydrogen production systems, a 30% KOH solution or a 26% NaOH solution is usually used as the electrolysis solution. Therefore, the generated hydrogen and oxygen will carry alkali solution, so the generated gas needs to be de-alkali misted by passing it through an oxygen-alkali separator 8 and a hydrogen-alkali separator 9.

[0036] One end of the hydrogen cooler 13 is fixedly connected to the hydrogen scrubber 11 via a pipe. The gas coming out of the oxygen-alkali separator 8 and the hydrogen-alkali separator 9 will still contain a small amount of misty alkali solution and water vapor. It can be further washed with water by the oxygen scrubber 10 and the hydrogen scrubber 11 to dissolve the trace amount of alkali solution in the water, thus ensuring the purity of oxygen and hydrogen. The oxygen cooler 12 and the hydrogen cooler 13 can be used to cool oxygen or hydrogen, making it easier to catch droplets through the drop catcher and improve purity. One end of the hydrogen-liquid separator 15 is fixedly connected to the hydrogen cooler 13 via a pipe.

[0037] Hydrogen and alkali solution enter the hydrogen-alkali separator 9 for separation, then enter the hydrogen scrubber 11 for washing, and then enter the hydrogen cooler 13 for cooling. After the gas-liquid mixture enters the separator, the hydrogen-liquid separator 15 and the oxygen-liquid separator 14 separate the heavier droplets flowing upwards from the hydrogen or oxygen bubbles in the gas gravity separation section, and remove the remaining droplets in the hydrogen or oxygen in the demister section of the separator to make the gas drier. After the water is separated by the hydrogen-liquid separator 15, it is sent to the storage tank or user.

[0038] In this embodiment, oxygen discharged from the separation system is used instead of compressed air generated by the air compressor 18 to supply air to the pneumatic components in each system. This allows the air compressor 18 to be shut down and stop working, effectively reducing the operating rate of the air compressor in the entire hydrogen production system, reducing power consumption, improving oxygen utilization, and lowering the cost of modifying the entire hydrogen production system, thus providing more possibilities for energy utilization in the hydrogen production system.

[0039] The above description represents a preferred embodiment of the present invention. The scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, combined with existing technology or common knowledge, and within the spirit and principles of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A compressed air supply device for an alkaline hydrogen production system, comprising a compressed air supply system and a separation system, a purification system, and other auxiliary systems connected to the compressed air supply system, characterized in that: The compressed air supply system includes a filter (17), an air compressor (18), and a control cabinet (19). One end of the air compressor (18) is fixedly connected to the filter (17) via a pipe, and the other end of the air compressor (18) is fixedly connected to the pressure gauge (7) and the electric ball valve (6) via a pipe. One end of the control cabinet (19) is fixedly connected to the electric ball valve (6) via a pipe. The control cabinet (19) is used to control the operation of the pneumatic components in each system. The separation system includes an oxygen-alkali liquid separator (8), an oxygen scrubber (10), an oxygen cooler (12), an oxygen-liquid separator (14), and a diaphragm valve (16). One end of the liquid separator (8) is used to introduce oxygen and alkali solution. The other end of the oxygen-alkali liquid separator (8) is fixedly connected to the oxygen scrubber (10) through a pipeline. One end of the oxygen scrubber (10) is fixedly connected to the oxygen cooler (12) through a pipeline. One end of the oxygen cooler (12) is fixedly connected to the oxygen-liquid separator (14) through a pipeline. One end of the oxygen-liquid separator (14) is fixedly connected to the diaphragm valve (16) through a pipeline. Oxygen is discharged through one end of the diaphragm valve (16). One end of the branch oxygen pipeline (1) is fixedly connected to the pipeline between the oxygen-liquid separator (14) and the diaphragm valve (16). The other end of the branch oxygen pipeline (1) A throttle valve (2) is fixedly connected via a pipe. A pressure reducing valve (3) is fixedly connected to one end of the throttle valve (2) via a pipe. An electric ball valve (5) is fixedly connected to one end of the pressure reducing valve (3) via a pipe. One end of a pressure sensor (4) is fixedly connected to the pipe between the pressure reducing valve (3) and the electric ball valve (5). An electric ball valve (6) is fixedly connected to one end of the electric ball valve (5) via a pipe. A pressure gauge (7) is fixedly connected to one end of the electric ball valve (6) via a pipe. Either the electric ball valve (5) or the electric ball valve (6) can be opened to supply power to the control cabinet (19) from the air compressor (18). The compressed air supply is provided, or the oxygen supply is provided by the branch oxygen pipeline (1); when the hydrogen production system starts working, the air compressor (18) in the compressed air supply system starts working, and at the same time, the electric ball valve two (6) is opened and the electric ball valve one (5) is closed to supply air to the control cabinet (19); when the reading of the pressure sensor (4) and the reading of the pressure gauge (7) reach a certain value, the air compressor (18) in the compressed air supply system stops, and at the same time, the electric ball valve two (6) is closed and the electric ball valve one (5) is opened, and the oxygen in the branch oxygen pipeline (1) replaces the compressed air to supply air to the control cabinet (19).

2. The compressed air supply device in an alkaline hydrogen production system according to claim 1, characterized in that, The oxygen discharged from one end of the oxygen-liquid separator (14) has an oxygen pressure of 3.2 MPa and a temperature of 65-85 degrees Celsius; the throttle valve (2) reduces the oxygen flow rate entering the branch oxygen pipeline (1) to 3.5 m³ / s. 3 / h, the pressure reducing valve (3) reduces the oxygen pressure in the branch oxygen pipeline (1) to 0.4MPa, and the air pressure at the outlet of the air compressor (18) is 0.4MPa and the flow rate is 3.5m. 3 / h, so that the pressure and flow rate of oxygen output from the branch oxygen pipeline (1) are consistent with the output pressure and flow rate of the compressed air supply system.

3. The compressed air supply device in an alkaline hydrogen production system according to claim 1, characterized in that, The separation system also includes a hydrogen-alkali separator (9), a hydrogen scrubber (11), a hydrogen cooler (13), and a hydrogen-liquid separator (15). One end of the hydrogen-alkali separator (9) is supplied with hydrogen and alkali. One end of the hydrogen scrubber (11) is fixedly connected to one end of the hydrogen-alkali separator (9) through a pipe. One end of the hydrogen cooler (13) is fixedly connected to the hydrogen scrubber (11) through a pipe. One end of the hydrogen-liquid separator (15) is fixedly connected to the hydrogen cooler (13) through a pipe.

4. The compressed air supply device in an alkaline hydrogen production system according to claim 3, characterized in that, Both the oxygen-liquid separator (14) and the hydrogen-liquid separator (15) are equipped with a gas gravity separation section and a demister. After the gas-liquid mixture enters, the gas gravity separation section first separates the heavier droplets flowing upward from the oxygen or hydrogen bubbles, and then the demister removes the remaining droplets in the oxygen or hydrogen.

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