PEM electrolytic bath operation state monitoring system

Abstract

The utility model belongs to the technical field of PEM water electrolysis hydrogen production, and particularly relates to a PEM electrolytic bath running state monitoring system. Comprising a one-way valve, a heat exchanger for cooling high-temperature hydrogen, a steam-water separator for separating moisture in the hydrogen, a drying tower for finely purifying the hydrogen and a gas mass flow meter which are sequentially connected in a hydrogen outlet pipeline of the PEM electrolytic cell, the heat exchanger and the steam-water separator are integrated on the same weighing platform, and the weighing platform and the gas mass flow meter are electrically connected with a controller. According to the utility model, the weighing platform is arranged below the heat exchanger and the steam-water separator for mass measurement, and the controller is combined for calculating the water permeability, so that the running state of the electrolytic cell is monitored in real time, and the water permeability is used as a key index for reflecting the running state of the PEM electrolytic cell to help operators to find potential problems of the electrolytic cell in time.

Description

A PEM electrolyzer operating status monitoring system Technical Field

[0001] This utility model belongs to the field of PEM electrolysis water production hydrogen technology, specifically relating to a PEM electrolyzer operation status monitoring system. Background Technology

[0002] In PEM (Polymer Electrolysis) water electrolysis for hydrogen production, the hydrogen produced by the PEM electrolyzer carries pressure and temperature, making it difficult for conventional volumetric flow meters to accurately measure its flow rate. According to the gas law, the volume of a gas is closely related to its pressure and temperature. Under actual operating conditions, fluctuations in pressure and temperature can cause changes in gas density, leading to significant deviations in the measurement results of volumetric flow meters based on ideal state assumptions.

[0003] Meanwhile, current technology is relatively weak in monitoring the health of PEM electrolyzers. Water permeability of the proton exchange membrane results in a large amount of moisture in the produced hydrogen. Although existing technologies have made some progress in hydrogen purification, little attention has been paid to real-time monitoring of the electrolyzer's health from the perspective of water permeability. In fact, water permeability is a key indicator reflecting the operating status of a PEM electrolyzer. Excessively high or abnormal water permeability may indicate damage or aging of the proton exchange membrane, affecting the electrolyzer's performance and lifespan.

[0004] Because there is currently a lack of effective means to measure and analyze the seepage rate in real time and accurately, potential health hazards in electrolytic cells cannot be detected in a timely manner, which often leads to delays in equipment maintenance, increasing the risk of production interruption and maintenance costs.

[0005] In view of this, the present invention provides a PEM electrolyzer operation status monitoring system to solve the above problems. Summary of the Invention

[0006] To achieve the above objectives, this utility model provides the following technical solution: a PEM electrolyzer operation status monitoring system, comprising: a one-way valve, a heat exchanger for cooling high-temperature hydrogen, a vapor-water separator for separating moisture from hydrogen, a drying tower for purifying hydrogen, and a gas mass flow meter, which are connected in sequence in the hydrogen outlet pipeline of the PEM electrolyzer.

[0007] The heat exchanger and the steam-water separator are integrated on the same weighing platform to measure the total mass of the heat exchanger and the steam-water separator in real time. The weighing platform and the gas mass flow meter are electrically connected to the controller.

[0008] Preferably, the system further includes a humidity sensor connected between the drying tower and the gas mass flow meter, the humidity sensor being electrically connected to the controller.

[0009] Preferably, the heat exchanger is a shell-and-tube heat exchanger or a plate heat exchanger.

[0010] Preferably, the steam-water separator is a gravity separator, a centrifugal separator, or a cyclone separator.

[0011] Preferably, the weighing platform is a digital electronic weighbridge.

[0012] Preferably, the humidity sensor is a capacitive humidity sensor or a resistive humidity sensor.

[0013] Preferably, the gas mass flow meter is a thermal mass flow meter.

[0014] Preferably, the controller is an industrial control computer or a programmable logic controller.

[0015] Compared with the prior art, the beneficial effects of this utility model are:

[0016] 1. This utility model uses a thermal hydrogen mass flow meter to measure the mass of hydrogen. Since the thermal mass flow meter is not affected by fluctuations in hydrogen pressure and temperature, it can directly measure the mass flow of hydrogen, thus achieving high-precision measurement of hydrogen production.

[0017] 2. This utility model achieves real-time monitoring of the electrolyzer's operating status by setting up a weighing platform below the heat exchanger and steam-water separator for mass measurement, and simultaneously calculating the water seepage rate using a controller. The water seepage rate is used as a key indicator reflecting the operating status of the proton exchange membrane in the PEM electrolyzer, helping operators to promptly detect potential aging, damage, and other problems of the proton exchange membrane.

[0018] 3. This utility model, by installing a humidity sensor between the drying tower and the gas mass flow meter, can determine the operating status of the drying tower by detecting the humidity value of the humidity sensor, so as to facilitate the operator to replace the desiccant in the tower in a timely manner, ensuring that the hydrogen entering the mass flow meter remains dry and pure, thereby maintaining the measurement accuracy. Attached Figure Description

[0019] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0020] Figure 1 is a schematic diagram of the overall structure of this utility model.

[0021] In the diagram: 1. PEM electrolytic cell; 2. Check valve; 3. Heat exchanger; 4. Steam-water separator; 5. Weighing platform; 6. Drying tower; 7. Humidity sensor; 8. Gas mass flow meter. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] Example 1:

[0024] This utility model relates to a PEM electrolyzer operation status monitoring system, as shown in Figure 1. It includes a one-way valve 2, a heat exchanger 3 for cooling high-temperature hydrogen, a vapor-water separator 4 for separating moisture from hydrogen, a drying tower 6 for purifying hydrogen, and a gas mass flow meter 8, all connected in sequence in the hydrogen outlet pipeline of the PEM electrolyzer 1. The heat exchanger 3 and the vapor-water separator 4 are integrated on the same weighing platform 5 to measure the total mass of the heat exchanger 3 and the vapor-water separator 4 in real time through the weighing platform 5. The weighing platform 5 and the gas mass flow meter 8 are electrically connected to the controller.

[0025] Specifically, the hydrogen outlet of PEM electrolyzer 1 is connected to a hydrogen delivery pipeline, which is responsible for transmitting the hydrogen produced by PEM electrolyzer 1 to subsequent processing and measurement components. On this hydrogen pipeline, key equipment such as check valve 2, heat exchanger 3, gas-liquid separator 4, drying tower 6, and gas mass flow meter 8 are arranged sequentially, and all equipment is securely connected by pipelines to ensure unobstructed hydrogen flow. Check valve 2 is installed immediately adjacent to the hydrogen outlet of PEM electrolyzer 1. Its construction typically involves a valve body with unidirectional conduction characteristics, equipped with a valve disc or valve core. When PEM electrolyzer 1 produces hydrogen, the gas pressure pushes the valve disc open, allowing the hydrogen to pass smoothly. If the pressure inside the pipeline fluctuates abnormally, potentially causing hydrogen backflow, the valve disc will quickly close under reverse pressure, effectively preventing hydrogen backflow and ensuring stable system operation. After check valve 2, heat exchanger 3 is connected; common types such as shell-and-tube heat exchangers or plate heat exchangers can be selected.

[0026] In this embodiment, a shell-and-tube heat exchanger is used as an example. It mainly consists of a shell, tube bundle, tube sheet, and end caps. Hydrogen gas flows into the tube side of the heat exchanger 3, while the cooling medium (such as water or other cooling fluid) flows in the shell side, exchanging heat through the tube walls to cool the high-temperature hydrogen gas. A vapor-water separator 4 is connected below the heat exchanger 3. The vapor-water separator 4 can be a gravity separator, a centrifugal separator, or a cyclone separator. In this embodiment, a gravity vapor-water separator is used as an example. It has a large separation space inside. After being cooled, the hydrogen gas carries a small amount of water into the separator. Due to the difference in density between the gas and the liquid, the liquid (water) gradually settles to the bottom of the separator under the action of gravity, and the dry gas is discharged from the top of the separator, completing the gas-liquid separation. The vapor-water separator 4 is connected to a drying tower 6 through a pipe. The drying tower 6 is filled with a desiccant, such as silica gel or molecular sieve. After preliminary purification by the gas-water separator 4, the hydrogen enters the drying tower 6, where trace amounts of moisture are adsorbed by the desiccant, achieving further drying and purification. A hydrogen outlet pipe is connected to the hydrogen outlet of the drying tower 6, and a gas mass flow meter 8 is installed. In this embodiment, the gas mass flow meter 8 is a thermal mass flow meter. Thermal mass flow meters operate based on the principle of heat conduction, determining the hydrogen mass flow rate by measuring the heat transfer relationship between the heating element and the gas. When hydrogen passes through the flow meter, the gas carries away heat from the heating element. Different flow rates of hydrogen carry away different amounts of heat. By detecting the temperature change of the heating element or the change in heating power required to maintain its constant temperature, the hydrogen mass flow rate can be calculated, and the flow data is transmitted to the controller.

[0027] Furthermore, to monitor the operating status of the PEM electrolyzer 1 via the permeation rate, the heat exchanger 3 and the steam-water separator 4 are placed on a weighing platform 5. In this embodiment, the weighing platform 5 is a digital electronic weighbridge or a high-precision electronic scale, capable of accurately measuring the weight changes of the heat exchanger 3 and the steam-water separator 4 due to the collection and separation of water, and transmitting the weight data to the controller in real time. The controller can be an industrial control computer or a programmable logic controller (PLC), etc., with a built-in algorithm program for the permeation rate. After receiving the weight data from the weighing platform 5 and the flow data from the gas mass flow meter 8, the controller, combined with the operating time of the PEM electrolyzer 1, calculates the permeation rate of the PEM electrolyzer 1 during operation using the algorithm. The permeation rate is used to determine the operating status of the proton exchange membrane in the PEM electrolyzer 1, facilitating timely maintenance by operators.

[0028] Example 2:

[0029] In order to facilitate the monitoring of the operating status of the drying tower 6, in addition to the technical solution provided in Embodiment 1, a humidity sensor 7 electrically connected to the controller is installed between the drying tower 6 and the gas mass flow meter 8.

[0030] Specifically, a humidity sensor 7 is first installed on the hydrogen outlet pipe connected to the hydrogen outlet of drying tower 6, followed by a gas mass flow meter 8. In this embodiment, the humidity sensor 7 can be a capacitive or resistive humidity sensor. It comes into full contact with the flowing hydrogen gas, senses the humidity of the hydrogen, and converts the humidity signal into an electrical signal, which is then transmitted to the controller. During use, when the humidity sensor 7 detects excessively high humidity, it indicates that the desiccant in drying tower 6 has failed. The controller can then issue an alarm to remind the user to replace the desiccant so that timely maintenance measures can be taken.

[0031] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A PEM electrolyzer operating status monitoring system, characterized in that, include: A one-way valve (2), a heat exchanger (3) for cooling high-temperature hydrogen, a steam-water separator (4) for separating moisture in hydrogen, a drying tower (6) for purifying hydrogen, and a gas mass flow meter (8) are connected in sequence in the hydrogen outlet pipeline of the PEM electrolyzer (1). The heat exchanger (3) and the steam-water separator (4) are integrated on the same weighing platform (5) so that the total mass of the heat exchanger (3) and the steam-water separator (4) can be measured in real time through the weighing platform (5). The weighing platform (5) and the gas mass flow meter (8) are electrically connected to the controller.

2. The PEM electrolyzer operating status monitoring system according to claim 1, characterized in that: It also includes a humidity sensor (7) connected between the drying tower (6) and the gas mass flow meter (8), the humidity sensor (7) being electrically connected to the controller.

3. The PEM electrolyzer operating status monitoring system according to claim 1, characterized in that: The heat exchanger (3) is a shell-and-tube heat exchanger or a plate heat exchanger.

4. The PEM electrolyzer operating status monitoring system according to claim 1, characterized in that: The steam-water separator (4) is a gravity separator, a centrifugal separator, or a cyclone separator.

5. The PEM electrolyzer operating status monitoring system according to claim 1, characterized in that: The weighing platform (5) is a digital electronic weighbridge.

6. The PEM electrolyzer operating status monitoring system according to claim 2, characterized in that: The humidity sensor (7) is a capacitive humidity sensor or a resistive humidity sensor.

7. The PEM electrolyzer operating status monitoring system according to claim 1, characterized in that: The gas mass flow meter (8) is a thermal mass flow meter.

8. The PEM electrolyzer operating status monitoring system according to claim 1, characterized in that: The controller is an industrial control computer or a programmable logic controller.

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