Gas permeation test system and method for anion exchange membrane electrolytic hydrogen production device

Abstract

The invention discloses a gas permeation test system and method for an anion exchange membrane electrolytic hydrogen production device. The gas permeation test system comprises: a to-be-tested electrolytic tank, wherein the to-be-tested electrolytic tank comprises an anode flow channel and a cathode flow channel which are separated by an anion exchange membrane; the electrolyte circulation assembly is communicated with one of the anode flow channel and the cathode flow channel, so that the electrolyte circulates between the electrolyte circulation assembly and the cathode flow channel or the anode flow channel; the pressure measuring assembly comprises a buffer tank, and the buffer tank is communicated with the sides, not connected with the electrolyte circulating assembly, of the cathode flow channel and the anode flow channel; the buffer tank is provided with a pressure measuring device used for monitoring the air pressure in the buffer tank. The problems that a gas permeation amount measurer of an anion exchange membrane electrolytic hydrogen production system is high in price and harsh in test condition can be solved.

Description

Technical Field

[0001] This invention relates to the field of hydrogen production technology, and specifically to a gas permeation testing system and method for an anion exchange membrane electrolysis hydrogen production device. Background Technology

[0002] Hydrogen is an energy carrier possessing both material and energy properties, playing a vital role in industrial production, electricity generation, electrosynthetic fuels, heating, and transportation. It permeates all sectors of the energy landscape and holds significant potential market value in global decarbonization. Renewable energy sources like wind power are intermittent, periodic, and geographically limited, posing challenges for large-scale, cross-seasonal energy storage. Hydrogen production via water electrolysis using renewable energy is an ideal method for large-scale, long-term energy storage. Furthermore, hydrogen is an important fuel and chemical feedstock in transportation, industry, power generation, and construction.

[0003] In electrolytic cells, diaphragms are typically used between the cathode and anode to isolate gases on both sides and improve gas purity. These diaphragms include inorganic diaphragms, organic polymer diaphragms, and organic-inorganic polymer diaphragms. While these diaphragms can isolate most gases, 100% gas isolation is not possible, especially under fluctuating power conditions. Measuring gas permeation is crucial for accurately assessing product gas purity and safety risks. Conventional gas permeation measurements are performed using sensors at the gas outlet, which involves demanding testing conditions and expensive sensors. Therefore, a solution is needed to address the issues of expensive gas permeation measuring instruments and demanding testing conditions in electrolytic hydrogen production systems. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a gas permeation testing system and method for an electrolytic hydrogen production device, thereby solving the issues of expensive gas permeation measuring instruments and stringent testing conditions in electrolytic hydrogen production systems.

[0005] This invention provides a gas permeation testing system for an electrolytic hydrogen production device, comprising: an electrolytic cell to be tested, the electrolytic cell including an anode channel and a cathode channel separated by a diaphragm; an electrolyte circulation assembly connected to either the anode channel or the cathode channel, allowing the electrolyte to circulate between the electrolyte circulation assembly and the cathode channel or the anode channel; and a pressure measuring assembly including a buffer tank connected to the side of the cathode channel and the anode channel not connected to the electrolyte circulation assembly; the buffer tank is equipped with a pressure measuring device for monitoring the gas pressure inside the buffer tank.

[0006] Optionally, the anode channel serves as the electrolyte side and is connected to the electrolyte circulation assembly, while the cathode channel serves as the non-electrolyte side and is connected to the buffer tank; or, the cathode channel serves as the electrolyte side and is connected to the electrolyte circulation assembly, while the anode channel serves as the non-electrolyte side and is connected to the buffer tank. Optionally, the gas permeation testing system of the electrolytic hydrogen production unit also includes: a current source, which is electrically connected to the cathode and anode of the electrolytic cell under test and provides output current.

[0007] Optionally, the current adjustment accuracy of the current source is higher than 0.1%, and the current and voltage data acquisition frequency of the current source is higher than 1ms.

[0008] Optionally, the electrolyte circulation assembly includes: an electrolyte storage tank, which is connected to the electrolyte consumption side of the electrolytic cell under test via an electrolyte pipeline; an electrolyte circulation pump is installed on the electrolyte pipeline to provide power for the circulation of the electrolyte.

[0009] Optionally, the buffer tank is connected to the non-electrolyte side of the electrolytic cell under test via a gas pipeline; the buffer tank is also connected to a liquid pressure relief pipeline and a gas pressure relief pipeline respectively; an electrolyte pressure relief valve is installed on the liquid pressure relief pipeline; and a shut-off valve is installed on the gas pressure relief pipeline.

[0010] This invention also provides a gas permeation testing method for an electrolytic hydrogen production device, using the gas permeation testing system for the electrolytic hydrogen production device provided by this invention; the method includes the following steps: initiating electrolyte circulation, causing the electrolyte to circulate between the electrolyte side and the electrolyte circulation assembly of the electrolytic cell under test; supplying power to the electrolytic cell under test, causing gas to be generated simultaneously on both the electrolyte side and the non-electrolyte side; the gas on the electrolyte side is carried away by the circulating electrolyte, while a portion of the gas generated on the non-electrolyte side flows into a buffer tank; the electrolyte liquids on the electrolyte side and the non-electrolyte side are isolated by an intermediate diaphragm, but the gas on both sides will slowly permeate to the other side through the intermediate diaphragm, and this permeation rate is proportional to the pressure on both sides. Because the pressure on the non-electrolyte side is much higher than the pressure on the electrolyte side, the gas flux permeating from the electrolyte side to the non-electrolyte side is much smaller than the gas flux permeating from the non-electrolyte side to the electrolyte side.

[0011] At this point, part of the gas in the buffer tank comes from the gas generated by electrolysis on the non-electrolyte side. This part of the gas increases the gas volume in the buffer tank and raises the gas pressure. Additionally, because the non-electrolyte gas permeates to the electrolyte side, this permeation reduces the gas volume in the buffer tank and lowers the gas pressure. Since the amount of gas generated by electrolysis is generally greater than the amount of gas permeated by permeation, adjusting the power supply current can gradually increase the pressure in the buffer tank until it stabilizes. This indicates that the amount of gas generated by electrolysis and the amount of gas permeating to the electrolyte side have reached equilibrium and are equal. Therefore, the amount of gas permeating to the electrolyte side can be indirectly measured by calculating the amount of gas generated by electrolysis at this point, as follows: Record the temperature T0 and the supply current I0 at this time; calculate the corresponding permeation flux according to the following formula. :

[0012] In the formula, R is the ideal gas constant; F is the Faraday constant; Tref is the pre-calibrated reference temperature; A is the permeation energy; substituting the permeation energy A corresponding to the pre-calibrated Tref into the formula, the permeation flux is calculated. According to the permeation flux The gas permeation status of the electrolytic cell under test is evaluated and calculated.

[0013] Optionally, in the step of adjusting the power supply current, the current is gradually increased from the initial value, which is 0.01% of the rated current of the electrolytic cell under test.

[0014] Optionally, during the process of adjusting the power supply current, as the current gradually increases, the adjustment range is 50%-100% of the initial current value each time.

[0015] Optionally, during the test, the buffer tank is only connected to the non-electrolyte side of the electrolytic cell under test, and all other external outlets are closed.

[0016] The beneficial effects of this invention are as follows: The gas permeation testing system for an electrolytic hydrogen production device provided by this invention connects the electrolyte circulation assembly to a single-sided flow channel of the electrolytic cell under test, allowing the electrolyte to circulate only in that single channel. If gas permeates, it will seep from the diaphragm to the side not supplied with electrolyte. A buffer tank is included to trap this permeated gas, allowing the gas permeation level in the channel connected to the electrolyte circulation assembly to the electrolytic cell under test to be calculated based on the gas pressure within the buffer tank. Similarly, to test the permeation level on the other side, the connection configurations of the electrolyte circulation assembly and pressure measuring assembly to the electrolytic cell under test can be interchanged. This gas permeation testing system for an electrolytic hydrogen production device features a simple component structure, easily achievable testing conditions, and low cost, solving the problems of expensive gas permeation measuring instruments and stringent testing conditions in electrolytic hydrogen production systems.

[0017] The gas permeation testing method for an electrolytic hydrogen production device provided by this invention utilizes the gas permeation testing system for the electrolytic hydrogen production device provided by this invention. Using the testing method provided in this embodiment, in the gas permeation testing system of the electrolytic hydrogen production device provided by this invention, the current is gradually increased until the gas pressure in the buffer tank no longer changes and tends to stabilize. The amount of gas generated at this point is considered to be the amount of gas permeating through the diaphragm. Because the pressure no longer changes at this point, the measured value is a steady-state value, which is convenient for calculation. This transforms the testing of gas permeation in the electrolytic cell into measuring the gas pressure in the buffer tank, and then into calculating the gas permeation flux, thereby allowing for the evaluation of the gas permeation situation of the electrolytic cell under test. Such a gas permeation testing method for an electrolytic hydrogen production device has easily achievable testing conditions and low cost, solving the problems of expensive gas permeation measuring instruments and harsh testing conditions in electrolytic hydrogen production systems. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the gas permeation testing system of an electrolytic hydrogen production apparatus according to an embodiment of the present invention; Figure 2 This is a schematic flowchart of a gas permeation testing method for an electrolytic hydrogen production apparatus according to an embodiment of the present invention. Detailed Implementation

[0020] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] In the description of this invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0022] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0023] Example 1 refer to Figure 1 This invention provides a gas permeation testing system for an electrolytic hydrogen production device, comprising: The electrolytic cell 2 under test includes an anode channel 21 and a cathode channel 23 separated by an anion exchange membrane 22.

[0024] The electrolyte circulation assembly 1 is connected to either the anode channel 21 or the cathode channel 23, so that the electrolyte circulates between the electrolyte circulation assembly 1 and the anode channel 21 or the cathode channel 23.

[0025] The pressure measuring assembly includes a buffer tank 4, which connects the cathode flow channel 23 and the side of the anode flow channel 21 that is not connected to the electrolyte circulation assembly 1. The buffer tank 4 is equipped with a pressure measuring device 5 for monitoring the gas pressure inside the buffer tank 4. The volume of the buffer tank 4 is less than 1 / 4 of the volume of the anode flow channel 21 or 1 / 4 of the volume of the cathode flow channel 23.

[0026] The gas permeation testing system for the electrolytic hydrogen production device provided in this embodiment generates gas on both the non-electrolyte side and the electrolyte side during energization testing. Due to the presence of the diaphragm 22, most of the gas remains within its respective flow channel. However, due to permeation, some gas permeates from the electrolyte side to the non-electrolyte side. Simultaneously, some gas also permeates from the non-electrolyte side to the electrolyte side. Furthermore, because the pressure on the non-electrolyte side is much greater than the pressure on the electrolyte side, the amount of gas permeating from the non-electrolyte side to the electrolyte side is much greater than the amount permeating from the electrolyte side to the non-electrolyte side. Therefore, during energization, gas is generated simultaneously in both flow channels, and gas also permeates through the diaphragm 22 into the opposite side. Since the buffer tank 4 is connected to the non-electrolyte side of the electrolytic cell 2 under test via the gas supply pipeline 8, an increase in the pressure of the buffer tank indicates that the gas generated on the non-electrolyte side is greater than the gas permeating out; a decrease in the pressure of the buffer tank indicates that the gas generated on the non-electrolyte side is less than the gas permeating out. When the pressure stabilizes and no longer changes, it is assumed that the amount of gas produced is equal to the amount that permeates out. The gas permeation status mentioned in the instruction manual mainly refers to the permeation from the non-electrolyte side to the electrolyte side (the permeation from the electrolyte side to the non-electrolyte side is extremely small and negligible). Therefore, the parameters such as the current and temperature at this point are related to the permeation amount, and the membrane 22 can be calculated using relevant formulas.

[0027] The gas permeation testing system of such an electrolytic hydrogen production device has a simple component structure, the testing conditions are easy to achieve, and the cost is low. It can solve the problems of expensive gas permeation measuring instruments and harsh testing conditions in electrolytic hydrogen production systems.

[0028] Specifically, the anode channel 21 serves as the electrolyte side and is connected to the electrolyte circulation assembly 1, while the cathode channel 23 serves as the non-electrolyte side and is connected to the buffer tank 4; or, the cathode channel 23 serves as the electrolyte side and is connected to the electrolyte circulation assembly 1, while the anode channel 21 serves as the non-electrolyte side and is connected to the buffer tank 4. In this embodiment, the anode channel 21 is connected to the electrolyte circulation assembly 1, and the cathode channel 23 is connected to the buffer tank 4.

[0029] Furthermore, the gas permeation testing system of the electrolytic hydrogen production device also includes a current source 3, which is electrically connected to the cathode (electrode in the cathode channel 23) and anode (in the anode channel 21) of the electrolytic cell 2 under test, providing output current. Typically, the current source 3 is equipped with an ammeter or multimeter to display relevant current, voltage, and other data related to the supplied current.

[0030] Specifically, the current adjustment accuracy of the current source is higher than 0.1%, and the current and voltage data acquisition frequency of the current source is higher than 1ms.

[0031] Furthermore, the electrolyte circulation assembly 1 includes: an electrolyte storage tank 11, which is connected to the electrolyte consumption side of the electrolytic cell under test via an electrolyte pipeline; an electrolyte circulation pump 13 is installed on the electrolyte pipeline to provide power for the circulation of the electrolyte. The electrolyte storage tank is also connected to an electrolyte source via a supply pipeline, which is equipped with a replenishment valve 12 to control the amount of electrolyte stored in the electrolyte storage tank 11.

[0032] Furthermore, the buffer tank 4 is connected to the non-electrolyte side of the electrolytic cell 2 under test via a gas supply line 8. The buffer tank 4 is also connected to a liquid pressure relief line and a gas pressure relief line. An electrolyte pressure relief valve 6 is installed on the liquid pressure relief line, and a shut-off valve 7 is installed on the gas pressure relief line. During the test, both the electrolyte pressure relief valve 6 and the shut-off valve 7 are closed, ensuring that the buffer tank 4 is only connected to the non-electrolyte side of the electrolytic cell 2 under test, maintaining a sealed state, thus facilitating accurate monitoring of the gas pressure inside the buffer tank 4. After the test is completed, when it is necessary to discharge the gas and liquid from the buffer tank 4, the electrolyte pressure relief valve 6 and the shut-off valve 7 are opened respectively to discharge the gas and liquid from the buffer tank 4, preventing residual gas and liquid from interfering with subsequent test results.

[0033] Example 2 This embodiment provides a gas permeation testing method for an electrolytic hydrogen production device, using the gas permeation testing system for the electrolytic hydrogen production device provided in Embodiment 1 above; the method includes the following steps: Start the electrolyte circulation to allow the electrolyte to circulate between the electrolyte side of the electrolytic cell under test and the electrolyte circulation assembly; When power is supplied to the electrolytic cell under test, gas begins to be generated on the electrolyte side and the non-electrolyte side, and some of the gas flows into the buffer tank. Adjust the power supply current to gradually increase the pressure inside the buffer tank until the pressure inside the buffer tank stabilizes and remains constant. Record the temperature T0 and the supply current I0 at this time; calculate the corresponding permeation flux according to the following formula. (Units: ml / min / cm² or mol / min / cm², i.e., osmotic volume / time / area):

[0034] In the formula, R is the ideal gas constant; F is the Faraday constant; Tref is the pre-calibrated reference temperature; and A is the permeation energy. The gas permeation test method provided in this embodiment substitutes the permeation energy A corresponding to the pre-calibrated Tref into the formula to calculate the permeation flux. According to the permeation flux The gas permeation status of the electrolytic cell under test is evaluated and calculated. For example, by using the above formula, the permeation energy A at other temperatures is calculated, and the gas permeation status of the electrolytic cell 2 under test is evaluated based on the permeation energy A. It can be seen that the gas pressure measured by the pressure measuring device 5 is irrelevant in the above calculation and evaluation process. Therefore, whether the pressure reading measured by the pressure measuring device 5 is caused purely by permeated gas, by mixed gas, or by non-permeated gas, it is irrelevant to the calculation process. Temperature T0 is the temperature inside the electrolytic hydrogen production device after gas equilibrium is achieved in the buffer tank 4 when the supply current value I0 is reached. It can be obtained by measuring and displaying the reading when the equilibrium is stable by setting thermometers at the inlet and outlet of the electrolyte pipeline or by setting a thermometer inserted into the electrolytic hydrogen production device. For the pre-calibrated Tref, it is usually selected as 20°C, i.e., Kelvin temperature 293K, and the corresponding permeation energy A can be found in public literature or databases. Thus, I0 and T0 are obtained from observation records, and Tref and A can be found, so the corresponding permeation flux can be obtained. This allows for the evaluation of membrane permeation at different temperatures (T).

[0035] The gas permeation testing method for such an electrolytic hydrogen production device has relatively easy-to-achieve test conditions and low cost, which can solve the problem of expensive gas permeation measuring instruments and harsh test conditions in electrolytic hydrogen production systems.

[0036] Furthermore, in the step of adjusting the power supply current, the current is gradually increased from the initial value, which is 0.01% of the rated current of the electrolytic cell under test. Since the amount of gas permeation is usually very small, the current is applied from an extremely low current until the current reaches the permeation stabilization point.

[0037] Furthermore, during the adjustment of the power supply current, as the current gradually increases, each adjustment increment is 50%-100% of the initial current value. Similarly, since the amount of gas permeation is usually very small, the adjustment increment is also based on the initial current value, i.e., 0.01% of the rated current of the electrolytic cell under test. Adjustments are then made in increments of 50%-100% of this initial current value to avoid insignificant changes due to excessively small increments or excessively large increments that exceed the permeation current by too much at once, thus distorting the test results.

[0038] Furthermore, during the test, the buffer tank is only connected to the non-electrolyte side of the electrolytic cell under test, while all other external outlets are closed. That is, during the test, both the electrolyte pressure relief valve and the shut-off valve are closed, ensuring the buffer tank is only connected to the non-electrolyte side of the electrolytic cell under test, maintaining a sealed state, thus facilitating accurate monitoring of the gas pressure inside the buffer tank. After the test is completed, when it is necessary to drain the gas and liquid from the buffer tank, the electrolyte pressure relief valve and the shut-off valve are opened respectively to drain the gas and liquid from the buffer tank, preventing residual gas and liquid from interfering with subsequent test results.

[0039] The technical solutions disclosed in this invention have been described above through embodiments. It is believed that those skilled in the art will understand this invention through the description of the above embodiments. Obviously, the above embodiments are merely examples for clear illustration and are not intended to limit the implementation. For those skilled in the art, other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all implementation methods here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A gas permeation testing system for an anion exchange membrane electrolysis hydrogen production device, characterized in that, include: An electrolytic cell to be tested, the electrolytic cell to be tested includes an anode channel and a cathode channel separated by an anion exchange membrane; An electrolyte circulation assembly is connected to one of the anode channel or the cathode channel, allowing the electrolyte to circulate between the electrolyte circulation assembly and the anode channel or the cathode channel; A pressure measuring component, comprising a buffer tank, the buffer tank being connected to the side of the cathode flow channel and the anode flow channel not connected to the electrolyte circulation component; the buffer tank is equipped with a pressure measuring device for monitoring the gas pressure inside the buffer tank.

2. The gas permeation testing system for the anion exchange membrane electrolysis hydrogen production device according to claim 1, characterized in that, The anode channel serves as the electrolyte side and is connected to the electrolyte circulation assembly, while the cathode channel serves as the non-electrolyte side and is connected to the buffer tank; alternatively, the cathode channel serves as the electrolyte side and is connected to the electrolyte circulation assembly, while the anode channel serves as the non-electrolyte side and is connected to the buffer tank.

3. The gas permeation testing system for the anion exchange membrane electrolysis hydrogen production device according to claim 2, characterized in that, Also includes: A current source is electrically connected to the cathode and anode of the electrolytic cell under test to provide an output current.

4. The gas permeation testing system for the electrolytic hydrogen production device according to claim 3, characterized in that, The current adjustment accuracy of the current source is higher than 0.1%, and the current and voltage data acquisition frequency of the current source is higher than 1ms.

5. The gas permeation testing system for the electrolytic hydrogen production device according to claim 2, characterized in that, The electrolyte cycling assembly includes: An electrolyte storage tank is connected to the electrolytic cell under test via an electrolyte pipeline; an electrolyte circulation pump is installed on the electrolyte pipeline to provide power for the circulation of the electrolyte.

6. The gas permeation testing system for the electrolytic hydrogen production apparatus according to claim 2, characterized in that, The buffer tank is connected to the non-electrolyte side of the electrolytic cell under test via a gas pipeline; the buffer tank is also connected to a liquid pressure relief pipeline and a gas pressure relief pipeline respectively; an electrolyte pressure relief valve is installed on the liquid pressure relief pipeline; and a shut-off valve is installed on the gas pressure relief pipeline.

7. A gas permeation test method for an electrolytic hydrogen production device, characterized in that, A gas permeation testing system using an electrolytic hydrogen production apparatus as described in any one of claims 2-6; comprising the following steps: Start the electrolyte circulation to circulate the electrolyte between the electrolyte side of the electrolytic cell under test and the electrolyte circulation assembly; When power is supplied to the electrolytic cell under test, gas begins to be generated on the non-electrolyte side, and part of the gas flows into the buffer tank. Adjust the power supply current to gradually increase the pressure inside the buffer tank until the pressure inside the buffer tank stabilizes and remains constant. Record the temperature T0 and the supply current I0 at this time; calculate the corresponding permeation flux according to the following formula. : In the formula, R is the ideal gas constant; F is the Faraday constant; Tref is the pre-calibrated reference temperature; A is the permeation energy; substituting the permeation energy A corresponding to the pre-calibrated Tref into the formula, the permeation flux is calculated. According to the permeation flux The gas permeation status of the electrolytic cell under test is evaluated and calculated.

8. The gas permeation test method for the electrolytic hydrogen production apparatus according to claim 7, characterized in that, In the step of adjusting the power supply current, the current is gradually increased from the initial value, which is 0.01% of the rated current of the electrolytic cell under test.

9. The gas permeation test method for the electrolytic hydrogen production device according to claim 8, characterized in that, In the step of adjusting the power supply current, as the current gradually increases, the adjustment range is 50%-100% of the initial current value each time.

10. The gas permeation test method for the electrolytic hydrogen production apparatus according to claim 7, characterized in that, During the test, the buffer tank is only connected to the non-electrolyte side of the electrolytic cell under test, and all other external outlets are closed.

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