High-pressure and high-humidity membrane separation testing system and method

Abstract

The invention relates to the field of separation membrane testing, in particular to a high-pressure and high-humidity membrane separation testing system and method. The testing system comprises a saturation chamber and a testing cavity, a first pressure controller used for controlling the pressure in the saturation chamber to be stable is arranged on an air inlet pipeline of the saturation chamber, and an air outlet of the saturation chamber is communicated with an air inlet of the testing cavity through a pipeline. A second pressure controller for controlling the pressure in the test cavity to be stable is arranged on an air inlet pipeline of the test cavity, a flow controller is arranged on an air outlet pipeline of the test cavity, and temperature and humidity sensors are arranged in the saturation chamber and the test cavity. The pressure of the saturation chamber and the test cavity is independently controlled, the flow controller is arranged, and the humidity of the test cavity is calibrated in real time based on the actually measured temperature and humidity, so that the problem that the humidity cannot be accurately controlled in a high-pressure environment is solved, and the humidity control precision and stability are improved; and reliable technical support is provided for the performance test of the separation membrane in a high-pressure and high-humidity environment.

Description

Technical Field

[0001] The present invention relates to the field of membrane testing, and specifically to a high-pressure and high-humidity membrane separation testing system and method. Background Art

[0002] As an important functional material, the separation membrane has broad application prospects in many fields such as gas separation, water treatment, and energy storage. Its separation performance is affected by various factors, among which humidity and pressure are key factors. In order to accurately evaluate the separation performance of the separation membrane under different working conditions, a series of strict tests are required, especially tests under high-pressure and high-humidity environments. Membrane materials often face extreme working conditions such as high pressure (e.g., 5 - 10 MPa in natural gas dehumidification) and high humidity (e.g., 80 - 100% RH in fuel cells) in practical applications. The accurate evaluation of its performance (such as permeability, selectivity, and mechanical stability) is crucial for material research and development and industrial applications. However, when the traditional membrane separation testing device conducts a humidity control test, it usually can only be carried out under normal pressure conditions. If a high-pressure test is to be carried out, only dry gas or gas with an uncertain specific humidity value can be selected for the test, and such a test is difficult to meet the test requirements under complex working conditions.

[0003] In practical applications, the separation membrane is often in an environment containing water vapor. Under different humidity conditions, the interaction between water molecules and the membrane material, as well as the influence of water molecules on the membrane pore structure and surface properties, are different. For example, water molecules may adsorb on the membrane surface, changing the charge distribution and hydrophilicity / hydrophobicity of the membrane surface, thereby affecting the adsorption and diffusion behavior of gas molecules on the membrane surface; water molecules may also enter the interior of the membrane pores, causing changes in the membrane pore size and affecting the transmission rate of gas molecules. These changes will have a significant impact on the separation performance of the separation membrane. Therefore, in laboratory tests, humidifying the test gas to simulate the actual working conditions and verifying the separation effect of the separation membrane under different humidities is of great significance for the design, optimization, and application of the separation membrane. Through humidification testing, the separation mechanism of the separation membrane under different humidity conditions can be deeply understood, providing a theoretical basis for developing separation membranes with better performance. Many industrial processes need to be carried out under high-pressure conditions. For example, in the natural gas purification process, in order to improve the gas separation efficiency and output, it is usually necessary to operate under a relatively high pressure; in the air separation field, a high-pressure environment helps to improve the separation purity of gases such as oxygen and nitrogen. In these high-pressure environments, the separation membrane not only has to withstand a relatively high pressure but also maintain good separation performance. The change in pressure will affect the diffusion coefficient of gas molecules and the mechanical properties of the membrane material. A relatively high pressure may cause the membrane material to undergo compressive deformation, changing the pore structure and thickness of the membrane, and thus affecting the transmission and separation effect of gas molecules in the membrane. Therefore, high-pressure testing of the separation membrane is an essential link. Only through high-pressure testing can the feasibility and reliability of the separation membrane in actual industrial applications be accurately evaluated.

[0004] At present, there is a lack of a high-pressure and high-humidity membrane separation test system in the market that specifically meets the test requirements of separation membranes under high pressure and high humidity. Existing high-pressure and high-humidity membrane separation test systems can either not withstand high pressure or cannot achieve precise humidity control under high-pressure environments. For example, some high-pressure and high-humidity membrane separation test systems applicable to normal-pressure environments have structures and materials that cannot withstand the stress under high-pressure conditions, and are prone to problems such as leakage, deformation, and even damage, and cannot meet the requirements of high-pressure tests. And some membrane separation test systems that can withstand a certain pressure are difficult to achieve precise humidity control under high-pressure environments due to limitations in humidity control principles or imperfect device structures. For example, the traditional dual-pressure method humidity generation device has a problem that the dead volume gas does not flow under high pressure, resulting in uncontrollable humidity, making the gas humidity distribution uneven during the test, and there is a large deviation between the test results and the actual application situation. This limitation seriously restricts the research and development and application promotion of separation membrane technology, resulting in researchers being unable to accurately evaluate the true performance of separation membranes under high-pressure and high-humidity environments, and delaying the development process of new separation membranes. It can be seen that in traditional membrane separation test devices, it is difficult to control humidity during high-pressure tests. When conducting humidity control tests, the pressure can only be selected as normal pressure, and only one of the high-pressure and humidity control test conditions can be selected. This situation obviously cannot meet the increasing test requirements of separation membranes. Summary of the Invention

[0005] The purpose of the present invention is to overcome the defect that the existing test system cannot achieve precise humidity control under high-pressure environments, and to provide a high-pressure and high-humidity membrane separation test system and method based on the dual-pressure method humidification principle, applicable to the separation performance test of separation membranes and capable of controlling the humidity of high-pressure test gases.

[0006] To solve the above technical problems, the technical solution adopted by the present invention is: a high-pressure and high-humidity membrane separation test system, including a saturation chamber and a test chamber. A first pressure controller for controlling the pressure stability in the saturation chamber is provided on the gas inlet pipeline of the saturation chamber. The gas outlet of the saturation chamber is connected to the gas inlet of the test chamber through a pipeline, and a second pressure controller for controlling the pressure stability in the test chamber is provided on the gas inlet pipeline of the test chamber. A flow controller is provided on the gas outlet pipeline of the test chamber. Temperature and humidity sensors are provided in both the saturation chamber and the test chamber.

[0007] Further, the test chamber includes an upper test chamber and a lower test chamber, and the specimen is located between the upper test chamber and the lower test chamber; the gas outlet of the saturation chamber is connected to the gas inlet of the upper test chamber through a pipeline, and the flow controller is provided on the gas outlet pipeline of the upper test chamber.

[0008] Further, the test lower chamber is provided with an air inlet and an air outlet. The air inlet of the test lower chamber is connected to a carrier gas source through Valve I, and the air outlet of the test lower chamber is connected to a gas analyzer through Valve II. Both Valve I and Valve II are three-way valves. Port a of Valve I is connected to the carrier gas source, Port c of Valve I is connected to the air inlet of the test lower chamber, Port a of Valve II is connected to the gas analyzer, Port c of Valve II is connected to the air outlet of the test lower chamber, and Port b of Valve I and Port b of Valve II are connected to each other.

[0009] Further, a vacuum pumping pipeline is provided between Valve I and the air inlet of the test lower chamber. The vacuum pumping pipeline includes a vacuum pump and a vacuum pumping control valve.

[0010] Further, the first pressure controller and the second pressure controller are proportional valves, electric pressure stabilizing valves or expansion valves.

[0011] Further, the flow controller is a proportional valve or an electrically regulated flow valve.

[0012] The present invention also discloses a high-pressure and high-humidity membrane separation test method, which is implemented based on the above test system and includes the following steps: S01. Place the separation membrane to be tested in the test chamber. According to the separation membrane test requirements, set the test humidity and test pressure, and determine the pressures of the saturation chamber and the test chamber according to the test requirements. S02. Introduce the test gas into the saturation chamber. During the introduction process, ensure that the pressure of the test gas introduced into the saturation chamber is the pressure value corresponding to the test humidity through the first pressure controller. S03. The test gas is in full contact with liquid water in the saturation chamber to humidify the test gas. The humidified test gas diffuses from the saturation chamber to the test chamber and is then emptied through the flow controller. During the diffusion process, ensure that the pressure of the humidified test gas diffusing into the test chamber is the test pressure through the second pressure controller and the flow controller. S04. The temperature and humidity sensors in the saturation chamber and the test chamber collect the temperature and humidity in the saturation chamber and the test chamber in real time. After the collected values are stable, perform dynamic calibration based on the real-time collected values to make the humidity in the test chamber gradually approach and stabilize at the test humidity. S05. The humidified test gas penetrates through the separation membrane under the action of the pressure difference. By detecting the permeation amount and composition of the gas permeating through the separation membrane, evaluate the separation performance of the separation membrane under different humidity and pressure conditions.

[0013] Further, the process of determining the pressures of the saturation chamber and the test chamber according to the test requirements is as follows: Let the test humidity value be , and the test pressure required by the test requirements is A. Then, according to the humidity control calculation formula of the dual-pressure method, it can be obtained that: , where is the saturated vapor pressure at the corresponding temperature, is the temperature of the saturation chamber, is the temperature of the test chamber, is the pressure of the test chamber, is the pressure of the saturation chamber; If the temperature of the saturation chamber is equal to the temperature of the test chamber before introducing the test gas, then: , If the pressure of the test chamber is set to test pressure A, then the pressure of the saturation chamber is .

[0014] Furthermore, the process of dynamic calibration based on real-time acquisition values is as follows: Let the humidity of the saturation chamber collected in real time be S1, and the temperature of the saturation chamber collected in real time be , then the partial pressure of water vapor in the saturation chamber is: , where is the saturated vapor pressure corresponding to the temperature of the saturation chamber collected in real time; When the humidified test gas diffuses from the saturation chamber to the test chamber, the partial pressure of water vapor changes according to the pressure ratio, then the partial pressure of water vapor in the test chamber is is: , Let the temperature of the test chamber collected in real time be , and the saturated vapor pressure corresponding to it be , then the actual humidity of the test chamber is: ; When the test chamber reaches the test humidity it needs to satisfy: , Then when the actual humidity of the test chamber reaches the test humidity , the pressure ratio of the test chamber and the saturation chamber needs to satisfy: , In this formula, , , , are all known quantities, and the pressure of the test chamber also remains at the test pressure. Calculate the pressure that the saturation chamber needs to reach during the dynamic calibration process based on the known quantities, and control the pressure of the saturation chamber to reach the calculated value through the first pressure controller, so as to ensure the accuracy of the humidity in the test chamber.

[0015] Further, when the pressure of the saturation chamber is controlled by the first pressure controller to reach the calculated value, the change in the pressure of the saturation chamber will affect the pressure of the test chamber. The second pressure controller and the flow controller are used to ensure that the pressure of the test chamber is stabilized at the test pressure.

[0016] Advantages of the present invention: 1. Realize high-pressure humidity control: Through the synergistic effect of the dual-pressure control device and the flow control device, the present invention successfully solves the problem of humidity control of the dual-pressure method humidity generation device in a high-pressure environment, and can achieve precise humidity control under high-pressure conditions. The humidity control accuracy can reach, meeting the requirements of high-pressure and high-humidity tests for separation membranes.

[0017] 2. Ensure gas fluidity: The setting of the flow control device effectively solves the problem of non-flowing dead-volume gas, ensures the continuous and stable flow of gas in the device, avoids the phenomenon of uneven humidity distribution caused by non-flowing gas, and improves the accuracy and reliability of test results.

[0018] 3. Fast response speed: The present invention inherits the advantage of the fast response speed of the dual-pressure method humidity generation principle, can quickly respond to the humidity change requirements, and the system can reach a stable humidity state in a short time during the humidity adjustment process, improving the test efficiency.

[0019] 4. Simple structure and convenient operation: The device has a compact structure, reasonable layout of each component, which is convenient for installation and maintenance. The operator can achieve precise control of parameters such as humidity and pressure only through simple parameter settings, reducing the operation difficulty and labor cost. Description of the drawings

[0020] Figure 1 It is a schematic block diagram of the test system described in Embodiment 1; 1. First pressure controller, 2. Humidification test control valve, 3. Ordinary test control valve, 4. Saturation chamber temperature and humidity sensor, 5. Second pressure controller, 6. Test chamber temperature and humidity sensor, 7. Upper test chamber, 8. Flow controller, 9. Saturation chamber, 10. Vacuum pump, 11. Vacuum control valve, 12. Lower test chamber, 13. Specimen, 14. Valve I, 15. Valve II, 16. Carrier gas source, 17. Gas analyzer. Detailed implementation manners

[0021] The present invention will be further described below with reference to the drawings and specific embodiments.

[0022] Embodiment 1 This embodiment discloses a high-pressure and high-humidity membrane separation test system, as Figure 1As shown, it includes a saturation chamber 9 and a test chamber, a first pressure controller 1 for controlling the pressure stability in the saturation chamber 9 is provided on the air inlet pipeline of the saturation chamber 9, the air outlet of the saturation chamber 9 is connected with the air inlet of the test chamber through a pipeline, and a second pressure controller 5 for controlling the pressure stability in the test chamber is provided on the air inlet pipeline of the test chamber, a flow controller 8 is provided on the air outlet pipeline of the test chamber, a saturation room temperature and humidity sensor 4 is provided in the saturation chamber 9, and a test chamber temperature and humidity sensor 6 is provided in the test chamber.

[0023] Specifically, the test chamber includes an upper test chamber 7 and a lower test chamber 12, and the sample 13 is located between the upper test chamber 7 and the lower test chamber 12; the gas outlet of the saturation chamber 9 is connected to the gas inlet of the upper test chamber 7 through a pipeline, and the flow controller 8 is arranged on the gas outlet pipeline of the upper test chamber 7. The lower test chamber 12 is provided with an inlet and an outlet, the inlet of the lower test chamber 12 is connected to the carrier gas source 16 through a valve I14, and the gas outlet of the lower test chamber 12 is connected to the gas analyzer 17 through a valve II15; the valve I14 and the valve II15 are both three-way valves, the port a of the valve I14 is connected to the carrier gas source 16, the port c of the valve I14 is connected to the gas inlet of the lower test chamber 12, the port a of the valve II15 is connected to the gas analyzer 17, the port c of the valve II15 is connected to the gas outlet of the lower test chamber 12, and the port b of the valve I14 is connected to the port b of the valve II15. A vacuum pumping pipeline is provided between valve I14 and the air inlet of the test lower chamber 12, and the vacuum pumping pipeline includes a vacuum pump 10 and a vacuum pumping control valve 11. In one state, valve I14 and valve II15 are only connected in one way, either ab is connected or ac is connected. When ab is connected, ac is in the cut-off state, and when ac is connected, ab is in the cut-off state. When ab is connected and ac is in the cut-off state, valve I14, valve II15 and the test lower chamber 12 can form a completely sealed chamber. The vacuum pumping pipeline can realize positive pressure testing and negative pressure testing. During the positive pressure test, the vacuum pipeline is first used to vacuum the test lower chamber 12 and its air inlet and outlet pipelines to eliminate the residual gas from the last test, and then it is restored to atmospheric pressure for testing. During the negative pressure test, the vacuum pipeline is first used to vacuum the test lower chamber 12 and its air inlet and outlet pipelines to eliminate the residual gas from the last test, and then the vacuum state is maintained for testing.

[0024] In this embodiment, a humidification test control valve 2 is provided between the air inlet of the saturation chamber 9 and the first pressure controller 1. A bypass is provided between the air inlet of the saturation chamber 9 and the air inlet of the upper test chamber 7, and a general test control valve 3 is provided on the bypass. When a test on the separation membrane under a certain humidity is required, the humidification test control valve 2 is opened and the general test control valve 3 is closed. The test gas passes through the first pressure controller 1 and the humidification test control valve 2 and enters the saturation chamber 9, where it comes into full contact with the liquid water and reaches a theoretically saturated state (RH = 100% in the ideal case), that is, a humidified test gas is formed. The humidified test gas enters the test chamber to complete the test. When the humidity is not required for the test of the separation membrane, the general test control valve 3 is opened and the humidification test control valve 2 is closed, and the test gas directly enters the test chamber for testing.

[0025] In this embodiment, the electronic or mechanical pressure stabilizing control components such as the first pressure controller 1 and the second pressure controller 5 are proportional valves, electric pressure stabilizing valves or expansion valves. The pressure controller has a pressure sensing function and adjusts the valve opening according to the sensed pressure, thereby realizing pressure control, that is, keeping the pressure at a set value. The saturation chamber adopts a closed-loop control with a dual pressure controller, and the pressure range is 0.1 - 10 Mpa; the test chamber dynamically adjusts the pressure and the exhaust flow rate through the PID algorithm, and the pressure difference from the saturation chamber is constant.

[0026] In this embodiment, the flow controller 8 is an electronically or mechanically adjusted flow valve. The flow controller has a flow sensing function and adjusts the valve opening according to the sensed flow rate, thereby realizing flow control, that is, keeping the flow rate at a set value. A flow controller 8 is provided at the air outlet of the upper test chamber 7, and the exhaust flow rate is adjusted according to the real-time pressure value (when the pressure is greater than the test pressure, the flow rate of the flow controller 8 increases to reduce the pressure; when the pressure is less than the test pressure, the flow rate of the flow controller 8 decreases to increase the pressure), ensuring a stable gas flow rate and eliminating the dead volume. The flow rate of the flow controller can be set according to the customer's needs, which can ensure the minimum flow rate required for the test and save the system power consumption.

[0027] The test system described in this embodiment is a high-precision humidity generating device based on the dual-pressure method principle. The dual-pressure method humidity control is a technology for controlling the relative humidity (RH) by adjusting the pressure difference between the saturation chamber and the test chamber. Through the optimization and upgrade of the structure, the problem that the dead volume gas does not flow under high-pressure environment and the humidity cannot be controlled is solved, ensuring the fluidity of the gas in the device and the uniformity of the humidity distribution, improving the accuracy and stability of humidity control, and providing reliable technical support for the performance test of the separation membrane under high-pressure and high-humidity environment.

[0028] The saturation chamber 9 and the test chamber are respectively pressure-controlled by independent pressure control devices. The pressure control device for the saturation chamber is used to maintain a stable pressure in the saturation chamber to ensure that water vapor can diffuse into the test chamber at a constant rate; the pressure control device for the test chamber precisely adjusts the pressure in the test chamber according to the test requirements to simulate the actual high-pressure test environment. By independently controlling the pressures of the saturation chamber and the test chamber, the stable operation of the dual-pressure humidity generation principle in a high-pressure environment is achieved, effectively avoiding the problem of unstable humidity control caused by pressure fluctuations in traditional dual-pressure devices under high pressure. A flow control device 8 is provided at the rear end of the test chamber. This device can control the exhaust flow rate of the test chamber in real time and automatically adjust the exhaust flow rate of the test chamber according to the preset flow rate value. By precisely controlling the exhaust flow rate, the continuous flow of gas in the device is ensured, and the formation of dead volume areas is avoided. At the same time, the flow control device and the pressure control device work together to dynamically adjust the pressure and flow rate of the test chamber according to the pressure change, ensuring that the gas flow state in the device always remains stable and the humidity distribution is uniform under different pressure conditions, thereby achieving precise humidity control of the gas under high pressure.

[0029] The working process of the test system described in this embodiment is as follows: First, according to the set humidity value, the set pressure values in the saturation chamber and the test chamber are calculated through relevant calculation formulas, and the saturation chamber and the test chamber are respectively pressurized to the set pressure values by the pressure control device. The water in the saturation chamber reaches a saturated state under high pressure and generates water vapor with a certain pressure. The water vapor diffuses into the test chamber under the action of the pressure difference for the separation performance test of the separation membrane. During the gas flow process, the flow control device adjusts the exhaust flow rate in real time according to the pressure of the test chamber to ensure the stable flow of gas in the device and maintain a constant humidity environment.

[0030] Embodiment 2 This embodiment discloses a high-pressure and high-humidity membrane separation test method, which is implemented based on the test system described in Embodiment 1 and includes the following steps: S01. Place the separation membrane to be tested in the test chamber (between the upper test chamber and the lower test chamber). According to the separation membrane test requirements, set the test humidity and test pressure, and determine the pressures of the saturation chamber and the test chamber according to the test requirements. Parameter settings can be performed through the system control panel or the host computer software to ensure the accuracy and repeatability of the parameters.

[0031] In this embodiment, the process of determining the pressures of the saturation chamber and the test chamber according to the test requirements is as follows: Let the test humidity value be , and the test pressure required by the test is A. Then, according to the dual-pressure humidity control calculation formula, we can obtain: , where is the saturated vapor pressure at the corresponding temperature, is the temperature of the saturation chamber, is the temperature of the test chamber, is the pressure of the test chamber, is the pressure of the saturation chamber; If the temperature of the saturation chamber is equal to the temperature of the test chamber before introducing the test gas, then: , Then the pressure ratio of the saturation chamber to the test chamber is: , Set the pressure of the test chamber to test pressure A, then the pressure of the saturation chamber is .

[0032] For example, if the required test humidity is 80%RH, the test pressure is 1Mpa, and the test flow rate is 100ml / min, according to the humidity control calculation formula of the dual-pressure method: , If the temperature of the saturation chamber is equal to the temperature of the test chamber before introducing the test gas, that is, ignoring the slight temperature difference between the saturation chamber and the test chamber, the formula is simplified to: , It can be calculated that the pressure setting of the pressure controller P2 is: 1.0Mpa; The pressure setting of the pressure controller P1 is: 1.25Mpa.

[0033] S02. Open the humidification test control valve 2 and close the ordinary test control valve 3. The test gas enters the saturation chamber 9 through the first pressure controller 1. During the process of introducing the test gas, ensure that the pressure of the test gas introduced into the saturation chamber 9 is the pressure value corresponding to the test humidity value through the first pressure controller 1.

[0034] S03. The test gas is in full contact with the liquid water in the saturation chamber 9 to humidify the test gas. The humidified test gas diffuses from the saturation chamber 9 to the test chamber under the action of the pressure difference and then is exhausted through the flow controller 8. During the diffusion process, ensure that the pressure of the humidified test gas diffused to the test chamber is the pressure value corresponding to the test humidity value through the second pressure controller 5 and the flow controller 8. The specific method is: when the pressure of the test chamber is greater than the test pressure, the opening of the second pressure controller 5 increases, the flow rate of the flow controller 8 increases, and the pressure decreases; when the pressure of the test chamber is less than the test pressure, the opening of the second pressure controller 5 decreases, the flow rate of the flow controller 8 decreases, and the pressure increases.

[0035] S04. The temperature and humidity sensors in the saturation chamber 9 and the test chamber collect the temperature and humidity in the saturation chamber and the test chamber in real time. After the collected values are stable, perform dynamic calibration based on the real-time collected values to make the humidity in the test chamber gradually approach and stabilize at the test humidity value.

[0036] In this embodiment, the process of dynamic calibration based on real-time acquisition values is as follows: Let the humidity real-time acquired by the saturation chamber be S1, and the temperature real-time acquired by the saturation chamber be , then the water vapor partial pressure of the saturation chamber is: , where is the saturated vapor pressure corresponding to the temperature real-time acquired by the saturation chamber; The humidified test gas diffuses from the saturation chamber to the test chamber, and the water vapor partial pressure changes according to the pressure ratio. Then the water vapor partial pressure of the test chamber is: , Let the temperature real-time acquired by the test chamber be , and its corresponding saturated vapor pressure be , then the actual humidity of the test chamber is: ; When the test chamber reaches the test humidity , it needs to satisfy: , Then when the actual humidity of the test chamber reaches the test humidity , the pressure ratio between the test chamber and the saturation chamber needs to satisfy: , In this formula, , , , are all known quantities, and the pressure of the test chamber also remains at the test pressure. Calculate the pressure that the saturation chamber needs to reach during the dynamic calibration process based on the known quantities, and control the pressure of the saturation chamber to reach the calculated value through the first pressure controller, so as to ensure the accuracy of the humidity in the test chamber.

[0037] Calculation example: Conditions: The temperature T1 of the saturation chamber = 30 °C, and the measured humidity S1 = 95%RH; The temperature T2 of the test chamber = 25 °C; The target test humidity RH target = 80%RH.

[0038] Steps: Calculate the saturated vapor pressure; Calculate Psat(T) through the Antoine equation: Psat(30 °C) ≈ 31.82 mmHg = 4.24 kPa, Psat(25℃) ≈ 23.76 mmHg = 3.17 kPa, Calculate the pressure ratio: , Adjust the pressure: If the pressure in the test chamber P2 is set to 1.0 MPa, the pressure in the saturation chamber needs to be adjusted to: , Verify the actual humidity: Substitute into the formula for verification: , it can be seen that the above pressure control process can keep the humidity in the test chamber as close as possible to the test humidity.

[0039] During the test process, the temperatures T1, T2 in the saturation chamber and the test chamber, and the humidities RH1, RH2 will be monitored in real time, and the pressure will be adjusted in real time to ensure the accuracy of the humidity.

[0040] When the pressure in the saturation chamber reaches the calculated value by controlling it with the first pressure controller, the change in the pressure in the saturation chamber will affect the pressure in the test chamber. The second pressure controller and the flow controller are used to ensure that the pressure in the test chamber is stable at the test pressure. This process can refer to the process of adjusting the pressure in the test chamber described in step S03.

[0041] S05. The humidified test gas passes through the separation membrane. By detecting the changes in the gas composition and flow rate on both sides of the separation membrane, the separation performance of the separation membrane under different humidity and pressure conditions is evaluated. Analytical instruments such as gas chromatographs and mass spectrometers can be used to accurately analyze the gas composition, and at the same time, a flow meter is used to measure the gas flow rate, so as to calculate performance indicators such as the separation factor and permeation flux of the separation membrane. Accurately analyzing the gas composition with gas chromatographs and mass spectrometers is a conventional technical means in the art and will not be elaborated here.

[0042] The above description only presents the basic principles and preferred embodiments of the present invention. The improvements and substitutions made by those skilled in the art based on the present invention fall within the protection scope of the present invention.

Claims

1. A high-pressure and high-humidity membrane separation test system, comprising a saturation chamber and a test chamber, characterized in that: A first pressure controller for controlling the stable pressure in the saturation chamber is provided on the air inlet pipeline of the saturation chamber. The air outlet of the saturation chamber is connected to the air inlet of the test chamber through a pipeline. And a second pressure controller for controlling the stable pressure in the test chamber is provided on the air inlet pipeline of the test chamber. A flow controller is provided on the air outlet pipeline of the test chamber. Temperature and humidity sensors are provided in both the saturation chamber and the test chamber.

2. The high-pressure and high-humidity membrane separation test system according to claim 1, wherein: The test chamber includes an upper test chamber and a lower test chamber. The specimen is located between the upper test chamber and the lower test chamber; the air outlet of the saturation chamber is connected to the air inlet of the upper test chamber through a pipeline, and the flow controller is arranged on the air outlet pipeline of the upper test chamber.

3. The high-pressure and high-humidity membrane separation test system according to claim 2, wherein: The lower test chamber is provided with an air inlet and an air outlet. The air inlet of the lower test chamber is connected to a carrier gas source through Valve I, and the air outlet of the lower test chamber is connected to a gas analyzer through Valve II; both Valve I and Valve II are three-way valves. Port a of Valve I is connected to the carrier gas source, Port c of Valve I is connected to the air inlet of the lower test chamber, Port a of Valve II is connected to the gas analyzer, Port c of Valve II is connected to the air outlet of the lower test chamber, and Port b of Valve I and Port b of Valve II are connected.

4. The high-pressure and high-humidity membrane separation test system according to claim 3, wherein: A vacuum pumping pipeline is provided between Valve I and the air inlet of the lower test chamber. The vacuum pumping pipeline includes a vacuum pump and a vacuum pumping control valve.

5. The high-pressure and high-humidity membrane separation test system according to claim 1, wherein: The first pressure controller and the second pressure controller are electronic or mechanical pressure stabilizing control components.

6. The high-pressure and high-humidity membrane separation test system according to claim 1, wherein: The flow controller is a flow valve regulated electronically or mechanically.

7. High-pressure and high-humidity membrane separation test method, characterized in that: This method is implemented based on the test system described in any one of claims 1-6, and includes the following steps: S01. Place the separation membrane to be tested in the test chamber. According to the test requirements of the separation membrane, set the test humidity and test pressure, and determine the pressures of the saturation chamber and the test chamber according to the test requirements. S02. Introduce the test gas into the saturation chamber. During the introduction process, ensure that the pressure of the test gas introduced into the saturation chamber is the pressure value corresponding to the test humidity through the first pressure controller. S03. The test gas is in full contact with liquid water in the saturation chamber to humidify the test gas. The humidified test gas diffuses from the saturation chamber to the test chamber and then is exhausted through the flow controller. During the diffusion process, ensure that the pressure of the humidified test gas diffused into the test chamber is the test pressure value through the second pressure controller and the flow controller. S04. The temperature and humidity sensors in the saturation chamber and the test chamber collect the temperature and humidity in the saturation chamber and the test chamber in real time. After the collected values are stable, perform dynamic calibration based on the real-time collected values to make the humidity in the test chamber gradually approach and stabilize at the test humidity. S05. The humidified test gas penetrates through the separation membrane under the action of the pressure difference. By detecting the permeation amount and composition of the gas penetrating through the separation membrane, evaluate the separation performance of the separation membrane under different humidity and pressure conditions.

8. The high-pressure and high-humidity membrane separation test method according to claim 7, characterized in that: The process of determining the pressures of the saturation chamber and the test chamber according to the test requirements of the specimen to be tested is: Set the test humidity value as , and if the test pressure required for the test is A, then according to the humidity control calculation formula of the dual-pressure method, it can be obtained that: ， wherein is the saturated vapor pressure at the corresponding temperature, is the temperature of the saturation chamber, is the temperature of the test chamber, is the pressure of the test chamber, is the pressure of the saturation chamber; If the temperature of the saturation chamber is equal to the temperature of the test chamber before introducing the test gas, then: ， If the pressure of the test chamber is set to test pressure A, then the pressure of the saturation chamber is .

9. The high-pressure and high-humidity membrane separation test system according to claim 7, characterized in that: The process of performing dynamic calibration based on the real-time collected values is: Let the humidity collected in real time in the saturation chamber be S1, and the temperature be , then the water vapor partial pressure in the saturation chamber is ， wherein is the saturated vapor pressure corresponding to the temperature collected in real time by the saturation chamber; The humidified test gas diffuses from the saturation chamber to the test cavity. If the water vapor partial pressure changes in proportion to the pressure, then the water vapor partial pressure in the test cavity is as follows: ， Let the temperature collected in real time in the test chamber be , and its corresponding saturated vapor pressure be . Then the actual humidity in the test chamber is: ； If the humidity in the test chamber reaches the test humidity Then it is necessary to meet the following: ×100%， Therefore, the actual humidity in the test chamber reaches the test humidity When this occurs, the pressure ratio between the test chamber and the saturation chamber must satisfy: ， In this formula, , , , are all known quantities, and the pressure in the test chamber is also maintained at the test pressure. The pressure that the saturation chamber needs to reach during the dynamic calibration process is calculated based on the known quantities, and the pressure of the saturation chamber is controlled by the first pressure controller to reach the calculated value, thereby ensuring the accuracy of the humidity in the test chamber.

10. The high-pressure and high-humidity membrane separation test method according to claim 9, characterized in that: When the pressure of the saturation chamber reaches the calculated value controlled by the first pressure controller, the change in the pressure of the saturation chamber will affect the pressure of the test chamber. Ensure the stability of the pressure of the test chamber through the second pressure controller and the flow controller.

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