Alkali liquor circulating system with hydrogen-oxygen pre-separator for alkaline water electrolytic bath
By installing a hydrogen-oxygen pre-separator at the outlet of the electrolyzer for preliminary gas-liquid separation, the leakage problem caused by the shared pipeline of hydrogen, oxygen, and liquid was solved, the hydrogen-oxygen pressure of the electrolyzer was stabilized, and the operational safety and reliability of the system were improved.
Patent Information
- Application Number
- CN202423205482.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-25
- Publication Date
- 2025-11-11
- Estimated Expiration
- 2034-12-25
AI Technical Summary
In existing alkaline water electrolysis equipment, the electrolyzer and the alkali separation system are placed separately, resulting in long hydrogen and oxygen pipelines that are prone to leakage. Furthermore, the hydrogen and oxygen pressure is unstable when the load fluctuates, affecting the safety and reliability of the system, which is particularly evident in green electricity hydrogen production scenarios.
A hydrogen-oxygen pre-separator is installed at the outlet of the electrolyzer to perform preliminary gas-liquid separation. The gas then enters the corresponding hydrogen-oxygen separator for further separation. This avoids sharing pipelines between hydrogen, oxygen, and liquid. Vertical or horizontal pre-separators are used to stabilize the gas-liquid separation process.
This completely solved the problem of scouring and leakage in the hydrogen-oxygen pipeline, stabilized the hydrogen-oxygen pressure balance in the electrolyzer, and improved the operational safety and reliability of the system.
Smart Images
Figure CN223535238U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of water electrolysis for hydrogen production technology, specifically to an alkaline solution circulation system for an alkaline water electrolyzer with a hydrogen-oxygen pre-separator. Background Technology
[0002] Existing alkaline water electrolysis hydrogen production equipment (such as...) Figure 1 The electrolyzer and alkali separation system are placed separately and need to be connected by pipelines. Because the pipelines from the hydrogen and oxygen outlets of the electrolyzer to the hydrogen and oxygen separators are long and have many bends, and because the hydrogen and oxygen pipelines at the electrolyzer outlet share gas and liquid flow, they are prone to scouring and leakage. Furthermore, changes in pressure loss in the hydrogen and oxygen pipelines during load variations affect the pressure balance on both sides of the electrolyzer, making it difficult to control the oxygen-in-hydrogen and hydrogen-in-oxygen ratios. This is especially problematic in green energy hydrogen production scenarios such as photovoltaic and wind power generation, where the fluctuating load characteristics cause the electrolyzer to operate under unstable conditions with large load fluctuations and frequent start-stop cycles (daytime operation and nighttime shutdown), affecting the safety and reliability of the electrolyzer system. Therefore, eliminating scouring and leakage in the hydrogen and oxygen pipelines at the electrolyzer outlet and stabilizing the oxygen-in-hydrogen and hydrogen-in-oxygen ratios under fluctuating load conditions has become a crucial research topic. Utility Model Content
[0003] The purpose of this invention is to overcome the above-mentioned shortcomings and provide an alkaline solution circulation system for an alkaline water electrolyzer with a hydrogen-oxygen pre-separator, which can effectively solve the problems of pipeline flushing and leakage and stable operation.
[0004] The purpose of this utility model is achieved as follows:
[0005] An alkaline solution circulation system for an alkaline water electrolyzer with a hydrogen-oxygen pre-separator includes an electrolyzer, a hydrogen separator, an oxygen separator, a hydrogen scrubber, an oxygen scrubber, an alkaline solution cooler, an alkaline solution circulation pump, a hydrogen cooler, and an oxygen cooler. The electrolyzer outlet is equipped with a hydrogen pre-separator and an oxygen pre-separator. The hydrogen outlet of the electrolyzer is connected to the gas-liquid mixing inlet of the hydrogen pre-separator. The liquid outlet of the hydrogen pre-separator is connected to the hydrogen separator via a first alkaline solution pipeline, and the gas outlet of the hydrogen pre-separator is connected to the hydrogen separator via a hydrogen pipeline. The oxygen outlet of the electrolyzer is connected to the gas-liquid mixing inlet of the oxygen pre-separator. The liquid outlet of the oxygen pre-separator is connected to the oxygen separator via a second alkaline solution pipeline, and the gas outlet of the oxygen pre-separator is connected to the oxygen separator via an oxygen pipeline.
[0006] Preferably, the hydrogen pre-separator and the oxygen pre-separator can be arranged vertically or horizontally.
[0007] Preferably, when multiple electrolyzers share a single separation system, each electrolyzer outlet is equipped with a hydrogen pre-separator and an oxygen pre-separator.
[0008] Preferably, the gas outlet of the hydrogen separator is connected to a hydrogen scrubber, the alkaline outlet of the hydrogen separator is connected to an alkaline cooler, the gas outlet of the oxygen separator is connected to an oxygen scrubber, the alkaline outlet of the oxygen separator is connected to an alkaline cooler, and the alkaline solution in the alkaline cooler is replenished into the electrolytic cell via an alkaline circulation pump.
[0009] Preferably, the hydrogen scrubber is connected to a hydrogen cooler, and the oxygen scrubber is connected to an oxygen cooler.
[0010] The beneficial effects of this utility model are:
[0011] A hydrogen pre-separator and an oxygen pre-separator are installed at the alkaline solution outlet of the electrolyzer. The hydrogen and alkaline solution exiting the electrolyzer undergo preliminary gas-liquid separation through the hydrogen pre-separator, and the oxygen and alkaline solution undergo preliminary gas-liquid separation through the oxygen pre-separator. After gas-liquid separation, the hydrogen and alkaline solution enter their respective oxygen separators and hydrogen separators through pipelines for secondary deep gas-liquid separation. Hydrogen and alkaline solution, as well as oxygen and alkaline solution, no longer share pipelines, thus completely solving the problem of scouring and leakage caused by the two-phase flow of hydrogen and oxygen pipelines. At the same time, it avoids the fluctuation of the pressure difference between the hydrogen and oxygen sides of the electrolyzer caused by the fluctuation of the two-phase flow resistance loss, which affects the performance indicators of hydrogen-oxygen and oxygen-hydrogen in the electrolyzer. Attached Figure Description
[0012] Figure 1 This is a diagram of the alkali solution circulation system of an existing alkaline water electrolysis cell.
[0013] Figure 2 This is a diagram of an alkaline solution circulation system for an alkaline water electrolyzer with a hydrogen-oxygen pre-separator according to this utility model.
[0014] The components include: electrolytic cell 1; hydrogen separator 2; oxygen separator 3; hydrogen scrubber 4; oxygen scrubber 5; alkali cooler 6; alkali circulation pump 7; hydrogen cooler 8; oxygen cooler 9; hydrogen pre-separator 10; oxygen pre-separator 11; first alkali pipeline 12; hydrogen pipeline 13; second alkali pipeline 14; and oxygen pipeline 15. Detailed Implementation
[0015] See Figure 2This utility model relates to an alkaline solution circulation system for an alkaline water electrolyzer with a hydrogen-oxygen pre-separator, comprising an electrolyzer 1, a hydrogen separator 2, an oxygen separator 3, a hydrogen scrubber 4, an oxygen scrubber 5, an alkaline solution cooler 6, an alkaline solution circulation pump 7, a hydrogen cooler 8, and an oxygen cooler 9. The outlet of the electrolyzer 1 is equipped with a hydrogen pre-separator 10 and an oxygen pre-separator 11. The hydrogen outlet of the electrolyzer 1 is connected to the hydrogen pre-separator 10. Hydrogen and alkaline solution undergo gas-liquid two-phase separation in the hydrogen pre-separator 10. The separated alkaline solution enters the hydrogen separator 2 through a first alkaline solution pipe 12, and the hydrogen enters the hydrogen separator 2 through a hydrogen pipe 13. The oxygen outlet of the electrolyzer 1 is connected to the oxygen pre-separator 11. Oxygen and alkaline solution undergo gas-liquid two-phase separation in the oxygen pre-separator 11. The separated alkaline solution enters the oxygen separator 3 through a second alkaline solution pipe 14, and the oxygen enters the oxygen separator 3 through an oxygen pipe 15.
[0016] The gas outlet of the hydrogen separator 2 is connected to the hydrogen scrubber 4, and the alkaline solution outlet of the hydrogen separator 2 is connected to the alkaline solution cooler 6. The gas outlet of the oxygen separator 3 is connected to the oxygen scrubber 5, and the alkaline solution outlet of the oxygen separator 3 is connected to the alkaline solution cooler 6. The alkaline solution in the alkaline solution cooler 6 is replenished into the electrolytic cell 1 via the alkaline solution circulation pump 7. The hydrogen scrubber 4 and the oxygen scrubber 5 are used to remove gaseous impurities and further improve the purity of hydrogen or oxygen.
[0017] The hydrogen scrubber 4 is connected to the hydrogen cooler 8, and the oxygen scrubber 5 is connected to the oxygen cooler 9.
[0018] The alkali solution in the alkali solution cooler 6 exchanges heat with the circulating cooling water to reduce the temperature of the alkali solution. The hydrogen gas in the hydrogen gas cooler 8 exchanges heat with the chilled water, and the oxygen gas in the oxygen gas cooler 9 exchanges heat with the chilled water to achieve the cooling of the hydrogen and oxygen.
[0019] The hydrogen pre-separator 10 and oxygen pre-separator 11 can be arranged vertically or horizontally.
[0020] When multiple electrolyzers 1 share a single separation system, each electrolyzer 1 is equipped with a hydrogen pre-separator 10 and an oxygen pre-separator 11 at its outlet. The hydrogen pre-separator 10 is connected to the hydrogen outlet of the corresponding electrolyzer 1, and the oxygen pre-separator 11 is connected to the oxygen outlet of the corresponding electrolyzer 1.
[0021] Working principle:
[0022] An alkaline solution is poured into the electrolytic cell, where water is electrolyzed to produce oxygen and hydrogen.
[0023] A gas-liquid mixture of hydrogen and alkali solution enters the hydrogen pre-separator from the hydrogen outlet of the electrolyzer, where the alkali solution and hydrogen undergo preliminary gas-liquid separation. The separated alkali solution then enters the hydrogen separator through the first alkali solution pipeline, and the hydrogen also enters the hydrogen separator through the hydrogen pipeline. A gas-liquid mixture of oxygen and alkali solution enters the oxygen pre-separator from the oxygen outlet of the electrolyzer, where the alkali solution and oxygen undergo gas-liquid separation. The separated alkali solution then enters the oxygen separator through the second alkali solution pipeline, and the oxygen also enters the oxygen separator through the oxygen pipeline. This process completely solves the problem of scouring and leakage caused by the two-phase flow in the hydrogen-oxygen pipeline, and at the same time avoids fluctuations in the two-phase flow resistance loss that cause fluctuations in the pressure difference between the hydrogen and oxygen sides of the electrolyzer, which would affect the performance indicators of hydrogen-oxygen and oxygen-hydrogen in the electrolyzer.
[0024] Hydrogen and alkaline solution enter the hydrogen separator separately, while oxygen and alkaline solution enter the oxygen separator separately for deep gas-liquid separation.
[0025] The separated hydrogen and oxygen are respectively fed into a hydrogen scrubber and an oxygen scrubber for purification. The separated alkaline solution is cooled and then fed back into the electrolytic cell via an alkaline solution circulation pump.
[0026] In addition to the above embodiments, this utility model also includes other implementation methods. All technical solutions formed by equivalent transformation or equivalent substitution should fall within the protection scope of the claims of this utility model.
Claims
1. An alkaline solution circulation system for an alkaline water electrolyzer with a hydrogen-oxygen pre-separator, comprising an electrolyzer, a hydrogen separator, an oxygen separator, a hydrogen scrubber, an oxygen scrubber, an alkaline solution cooler, an alkaline solution circulation pump, a hydrogen cooler, and an oxygen cooler, characterized in that: The electrolytic cell is equipped with a hydrogen pre-separator and an oxygen pre-separator at its outlet. The hydrogen outlet of the electrolytic cell is connected to the gas-liquid mixing inlet of the hydrogen pre-separator. The liquid outlet of the hydrogen pre-separator is connected to the hydrogen separator via a first alkali solution pipeline, and the gas outlet of the hydrogen pre-separator is connected to the hydrogen separator via a hydrogen pipeline. The oxygen outlet of the electrolytic cell is connected to the gas-liquid mixing inlet of the oxygen pre-separator. The liquid outlet of the oxygen pre-separator is connected to the oxygen separator via a second alkali solution pipeline, and the gas outlet of the oxygen pre-separator is connected to the oxygen separator via an oxygen pipeline.
2. The alkaline solution circulation system for an alkaline water electrolyzer with a hydrogen-oxygen pre-separator according to claim 1, characterized in that: The hydrogen pre-separator and oxygen pre-separator can be arranged vertically or horizontally.
3. The alkaline solution circulation system for an alkaline water electrolyzer with a hydrogen-oxygen pre-separator according to claim 1, characterized in that: When multiple electrolyzers share a single separation system, each electrolyzer is equipped with a hydrogen pre-separator and an oxygen pre-separator at outlet 1.
4. The alkaline solution circulation system for an alkaline water electrolyzer with a hydrogen-oxygen pre-separator according to claim 1, characterized in that: The gas outlet of the hydrogen separator is connected to a hydrogen scrubber, and the alkaline outlet of the hydrogen separator is connected to an alkaline cooler. The gas outlet of the oxygen separator is connected to an oxygen scrubber, and the alkaline outlet of the oxygen separator is connected to an alkaline cooler. The alkaline solution in the alkaline cooler is replenished into the electrolytic cell via an alkaline circulation pump.
5. The alkaline solution circulation system for an alkaline water electrolyzer with a hydrogen-oxygen pre-separator according to claim 4, characterized in that: The hydrogen scrubber is connected to a hydrogen cooler, and the oxygen scrubber is connected to an oxygen cooler.