Multifunctional fuel cell cathode foreign gas filtering and testing system

Abstract

The invention discloses a multifunctional fuel cell cathode impurity gas filtering and testing system. The device comprises a gas supply system, a fixed bed reaction system and a gas analysis system, a temperature and vibration control system is arranged in the fixed bed reaction system, and the gas supply system, the fixed bed reaction system and the gas analysis system are sequentially connected through gas pipelines; a differential pressure sensor is connected between the gas supply system and the fixed bed reaction system, and a differential pressure sensor is connected between the fixed bed reaction system and the gas analysis system; the tail part of the gas analysis system is connected with a tail gas absorption bottle. According to the invention, the problem that foreign gas exists in the use environment of the fuel cell in the related art is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of gas filtration, and in particular to a multifunctional fuel cell cathode impurity gas filtration test system. Background Art

[0002] In recent years, with the rapid development of society, the economy, and science and technology, global energy consumption has increased significantly, particularly in industrial production and transportation. However, this has also led to an increase in global greenhouse gas emissions, severely impacting the Earth's environment. Consequently, many countries are actively searching for new energy sources to replace the traditional energy sources currently used. Many developed countries are focusing on hydrogen energy technologies, particularly fuel cells, and have formulated hydrogen energy development strategies, believing that proton exchange membrane fuel cells (PEMFCs) are the most promising high-efficiency, clean energy device of the 21st century. Their numerous advantages, such as low emissions, high efficiency, and rapid start-up, make them ideally suited as a power source for mobile vehicles.

[0003] The performance degradation of PEMFC is one of the most critical challenges hindering the widespread application of this technology. Due to the extensive use of fossil energy, there are a large number of impurities (pollutants) in the air. These pollutants will poison the catalyst of PEMFC, increase activation loss, and lead to a decline in fuel cell performance. Among them, SO2, NO X and VOCs will cause varying degrees of poisoning to the fuel cell. Therefore, when operating a fuel cell vehicle in a real environment, how to prevent pollutants in the atmosphere from affecting the cathode catalyst becomes a challenge. The solution is mainly to add an air filter to the cathode side of the fuel cell. The activated carbon and other adsorption materials in the air filter can adsorb pollutants in the air and purify the air, thereby improving the performance and durability of the fuel cell. Due to the important role of the fuel cell air filter, the test and evaluation of its impurity gas filtration effect is particularly important. It is necessary to develop an advanced multifunctional fuel cell cathode impurity gas filtration test system to meet the needs of fuel cell air filter testing.

[0004] Existing systems for impurity gas filtration testing, such as the invention patent with publication number CN108535166A, include a particulate air filter, an activated carbon adsorption filter, a pollutant generator bottle, a humidifier bottle, and the like. The main drawbacks of this system are that the pollutant gas (impurity gas) is single, cannot be accurately proportioned, and lacks an exhaust gas treatment device. The invention patent with publication number CN104677770B connects the system to the host computer via a temperature and humidity sensor, a pressure sensor, a temperature and humidity controller, an electromagnetic flowmeter, a solenoid valve, and other components to achieve automated control of temperature, humidity, and air pressure within the system. Its main drawback is that the gas concentration detector within the system is constantly exposed to the test gas (polluted gas) during the test, which is detrimental to the long-term precision detection of the sensor and hinders the long-term stable operation of the system. Existing air filters for adsorbing pollutants in the fuel cell field, such as the invention patent with publication number CN101439250B, include a filter housing, a physical filter element, and a chemical filter element. The physical filter element uses paper material or non-woven fabric as the filter element material, while the chemical filter element uses a chemical adsorbent as the filter element material. The main disadvantages of this structure are that it is difficult to disassemble, which makes it difficult to replace the adsorbent, and it cannot be used with a variety of adsorbent materials. Patent US7101419B2 designs an air filter for a low-temperature catalytic reaction process. This filter can remove particulate pollutants and polluted gases in the air, but the entire filter structure is not compact enough and cannot control the uniformity of the air flow within the filter. Summary of the Invention

[0005] The purpose of the present invention is to provide a multifunctional fuel cell cathode impurity gas filtration test system to solve the problem of impurity gas existing in the use environment of the fuel cell in the related art.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A multifunctional fuel cell cathode impurity gas filtration test system includes a gas supply system, a fixed-bed reaction system and a gas analysis system. The fixed-bed reaction system is provided with a temperature and vibration control system, which is sequentially connected to the gas supply system, the fixed-bed reaction system and the gas analysis system through a gas pipeline; a pressure differential sensor is connected between the gas supply system and the fixed-bed reaction system, and a pressure differential sensor is connected between the fixed-bed reaction system and the gas analysis system; and an exhaust gas absorption bottle is connected to the tail of the gas analysis system.

[0008] It is further configured as follows: the fixed bed reaction system includes a main body, end covers, quick-plug connectors, raw tape, wire mesh, adsorbent material, and a cylindrical fixed bed reactor; the end covers are installed on both sides of the fixed bed reactor, and the end covers are fastened and sealed by raw tape; the quick-plug connectors are installed on the outermost side of the fixed bed reaction system, and the quick-plug connectors are used to connect to the air intake and exhaust pipes; the wire mesh is installed on both sides of the inside of the fixed bed reactor.

[0009] It is further configured as follows: the gas supply system includes an air generator, an impurity gas bottle, a steam generator, a two-way valve, a polytetrafluoroethylene tube, a flow controller, a four-way valve and a first three-way valve; the impurity gas bottle is filled with at least one impurity gas; the steam generator is used to provide water vapor to provide a set humidity for the mixed gas; the four-way valve and the first three-way valve collect different component gases and lead them to the fixed bed reaction system; the air generator includes an air compressor, a silica gel particle filter, a valve and a pressure regulating tank, and the silica gel particle filter is used to filter impurities in the air; the outlet of the air generator outputs pressurized pure air.

[0010] It is further configured as follows: a two-way valve connects the air inlet and the flow controller, which is used to open and close different air paths to control the type of impurity gas; the flow controller is used to proportion different types of impurity gases, water vapor and air according to needs to obtain a single impurity gas or a multi-impurity mixed gas with a precise concentration; according to different impurity gas requirements, flow controllers of different ranges are replaced.

[0011] It is further configured as follows: the temperature and vibration control system includes a temperature control box, a temperature sensor and a vibration test bench; the fixed bed reactor is completely placed in the temperature control box, and the temperature sensors are set at the inlet and outlet of the fixed bed reactor; the fixed bed reactor is set on the vibration test bench in the temperature control box, and the vibration test bench is used to excite transverse and longitudinal waves with controllable frequency and amplitude to simulate the vibration of actual road conditions.

[0012] It is further configured as follows: a differential pressure sensor is used to collect differential pressure; and differential pressure sensors of different ranges are replaced according to needs.

[0013] It is further configured as follows: the gas analysis system includes a second three-way valve, a third three-way valve, a time relay, a first solenoid valve, a second solenoid valve and a multi-component gas analyzer; the inlet of the second three-way valve is connected to the fixed bed reaction system, and the outlet is respectively connected to the first solenoid valve and the tail gas absorption bottle; the inlet of the multi-component gas analyzer is connected to the third three-way valve, and the outlet of the multi-component gas analyzer is connected to the tail gas absorption bottle.

[0014] It is further configured as follows: the inlet of the first solenoid valve is connected to the second three-way valve, and the outlet of the first solenoid valve is connected to the third three-way valve; the inlet of the second solenoid valve is connected to the air generator, and the outlet of the second solenoid valve is connected to the third three-way valve; the first solenoid valve and the second solenoid valve are each connected to a time relay, and the two time relays control the first solenoid valve and the second solenoid valve respectively.

[0015] It is further configured as follows: when the multi-component gas analyzer needs to be purged, the first solenoid valve is closed and the second solenoid valve is opened to allow pure air to enter the multi-component gas analyzer; the opening time of the second solenoid valve is synchronized with the closing time of the first solenoid valve.

[0016] It is further configured as follows: an acid solution or an alkaline solution and an acid-base indicator are contained in the tail gas absorption bottle, an acid solution or an alkaline solution is selected for neutralization according to the acidity or alkalinity of the impurity gas, and whether the acid solution or the alkaline solution is ineffective is judged according to the color of the acid-base indicator.

[0017] Compared with the prior art, the beneficial technical effects of the present invention are:

[0018] Flow controllers with varying ranges are used to precisely measure the concentration of single or mixed air impurity gases. The system also offers multi-gas analysis capabilities, enabling testing of fuel cell air filter penetration curves, unit adsorption capacity, and pressure drop, as well as accurate control of gas flow, impurity concentration, temperature, and humidity. The proportioned air supply system includes saturated steam for humidity control, enabling research into impurity filtration tests at varying humidity levels. The vibration test bench controls the excitation frequency and amplitude of the fixed-bed reactor, simulating the effects of vibration on the air filter's adsorption characteristics during actual road operation of fuel cell vehicles. High-concentration pollutant flow adsorption data can be used to estimate the service life of fuel cell air filters operating under realistic low-concentration pollutant conditions, effectively guiding air filter element replacement. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 is the breakthrough curve of activated carbon to SO2 under different gas flow rates; Figure 3 is the breakthrough curve of activated carbon to SO2 at different fixed bed heights; Figure 4 is the unit adsorption capacity of activated carbon for SO2 at different SO2 concentrations; Figure 5 The breakthrough curves of SO2 adsorption on different activated carbons; Figure 6 is the unit adsorption capacity of activated carbon for SO2; Figure 7 This is a method for estimating the service life of fuel cell air filter elements.

[0021] Figure numerals: 1. two-way valve; 2. flow controller; 3. four-way valve; 4. first three-way valve; 5. differential pressure sensor; 6. wire mesh; 7. adsorbent material; 8. fixed bed reactor; 9. vibration test bench; 10. temperature sensor; 11. temperature control box; 12. time relay; 13. first solenoid valve; 14. second solenoid valve; 15. second three-way valve; 16. third three-way valve; 17. multi-component gas analyzer; 18. tail gas absorption bottle. DETAILED DESCRIPTION

[0022] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0023] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0025] Example 1

[0026] Reference Figure 1, which is a multifunctional fuel cell cathode impurity gas filtration test system disclosed in the present invention, and includes: a gas supply system, a fixed bed reaction system and a gas analysis system. The fixed bed reaction system is provided with a temperature and vibration control system, which is connected in sequence through a gas pipeline to the gas supply system, the fixed bed reaction system and the gas analysis system; a pressure difference sensor 5 is connected between the gas supply system and the fixed bed reaction system, and a pressure difference sensor 5 is connected between the fixed bed reaction system and the gas analysis system; and an exhaust gas absorption bottle 18 is connected to the tail of the gas analysis system.

[0027] Optionally, the fixed bed reaction system includes a main body, end covers, quick-plug connectors, raw tape, wire mesh 6, adsorbent material 7, and a cylindrical fixed bed reactor 8; the end covers are installed on both sides of the fixed bed reactor 8, and the end covers are fastened and sealed by raw tape; the quick-plug connectors are installed on the outermost side of the fixed bed reaction system, and the quick-plug connectors are used to connect to the air intake and exhaust pipes; the wire mesh 6 is installed on both sides of the inside of the fixed bed reactor 8.

[0028] Specifically, the main material of the fixed bed reactor 8 is transparent acrylic, which can withstand the temperature change of the adsorbent adsorption. The end cover is made of aluminum alloy to reduce weight and improve corrosion resistance. The wire mesh 6 is used to fix the adsorbent material 7 filled inside to prevent the adsorbent material 7 from moving during the experiment, and also to prevent the adsorbent material 7 from falling off and entering the exhaust pipe. The installation of the wire mesh 6 also helps to change the air flow to obtain a more uniform air flow distribution. The adsorbent material 7 filled inside the reactor can be a granular adsorbent material 7 such as activated carbon or a sheet-like fiber adsorbent material 7. The fixed bed reactor 8 is detachable and can be equipped with different diameters and lengths to change the volume of the filled adsorbent material 7, simulate air filters of various sizes to match different intake flow rates of fuel cells and carry out structural parameter impact tests.

[0029] Optionally, the gas supply system includes an air generator, an impurity gas bottle, a steam generator, a two-way valve 1, a polytetrafluoroethylene tube, a flow controller 2, a four-way valve 3 and a first three-way valve 4; the impurity gas bottle contains at least one impurity gas; the steam generator is used to provide water vapor to provide a set humidity for the mixed gas; the four-way valve 3 and the first three-way valve 4 collect different component gases and lead them to the fixed bed reaction system; the air generator includes an air compressor, a silica gel particle filter, a valve and a pressure regulating tank, and the silica gel particle filter is used to filter impurities in the air; the outlet of the air generator outputs pressurized pure air.

[0030] Specifically, the air generator consists of an air compressor, a silica gel filter, valves, a surge tank, and other accessories. The silica gel filter filters impurities and dries the air, providing stable, clean air. The air generator outlet delivers pure air at a specific pressure. Impurity gas cylinders, including SO2, NOx, NH3, VOC, and other impurity gas cylinders, provide the system with a variety of impurity gases. A steam generator provides water vapor to the system, providing a set humidity for the mixed gas.

[0031] Optionally, the two-way valve 1 connects the air inlet and the flow controller 2 to open and close different air paths to control the type of impurity gas; the flow controller 2 is used to proportion different types of impurity gases, water vapor and air according to demand to obtain a single impurity gas or a multi-impurity mixed gas with precise concentration; according to different impurity gas requirements, the flow controller 2 of different ranges is replaced.

[0032] Specifically, a two-way valve 1 connects the air inlet to a flow controller 2, opening and closing different gas paths according to system requirements to control the types of impurity gases. Flow controller 2 proportions different types of impurity gases, water vapor, and air according to system requirements, thereby producing a single impurity gas or a multi-impurity mixed gas with precise concentrations. A four-way valve 3 and a first three-way valve 4 collect and direct the different gas components to the fixed-bed reaction system. The gas supply system can replace flow controllers 2 with different ranges to precisely proportion and produce the desired mixed gas, depending on the impurity gas requirements.

[0033] Optionally, the temperature and vibration control system includes a temperature control box 11, a temperature sensor 10 and a vibration test bench 9; the fixed bed reactor 8 is completely placed in the temperature control box 11, and the temperature sensor 10 is arranged at the inlet and outlet of the fixed bed reactor 8; the fixed bed reactor 8 is arranged on the vibration test bench 9 in the temperature control box 11, and the vibration test bench 9 is used to excite transverse and longitudinal waves with controllable frequency and amplitude to simulate the vibration of actual road conditions.

[0034] Specifically, during the test, the fixed bed reactor 8 needs to be completely placed in the temperature control box 11 for sufficient heat exchange, and the temperature is measured by the temperature sensors 10 installed at the inlet and outlet of the fixed bed reactor 8 .

[0035] Optionally, the differential pressure sensor 5 is used to collect the pressure difference; the differential pressure sensor 5 of different ranges can be replaced according to the needs. The pressure drop collection system can replace the differential pressure sensor 5 of different ranges according to the system needs to accurately measure the inlet and outlet pressure difference of the fixed bed reactor 8.

[0036] Optionally, the gas analysis system includes a second three-way valve 15, a third three-way valve 16, a time relay 12, a first solenoid valve 13, a second solenoid valve 14 and a multi-component gas analyzer 17; the inlet of the second three-way valve 15 is connected to the fixed bed reaction system, and the outlet is respectively connected to the first solenoid valve 13 and the exhaust gas absorption bottle 18; the inlet of the multi-component gas analyzer 17 is connected to the third three-way valve 16, and the outlet of the multi-component gas analyzer 17 is connected to the exhaust gas absorption bottle 18.

[0037] Specifically, if the internal sensors of the multi-component gas analyzer 17 are exposed to an impurity gas environment for a long time, it will cause component loss, which is not conducive to the long-term stable and accurate measurement of gas components. Therefore, this system combines the first solenoid valve 13 and the second solenoid valve 14 through the time relay 12, and can set the collection time according to the system requirements. The second solenoid valve 14 is in a normally closed state. When the first solenoid valve 13 is opened, it is in the mixed gas component collection mode, that is, the working mode (working time T1). When the first solenoid valve 13 is closed, it is in the non-working mode. When the first solenoid valve 13 is closed, the second solenoid valve 14 opens and lasts for a period of T2 before closing. During the period when the second solenoid valve 14 is open, pure air is used to purge the residual mixed gas in the multi-component gas analyzer 17 to avoid continuous damage to the built-in sensor of the gas analyzer by the contaminated gas.

[0038] T1 can be determined by measuring the shortest time from the opening of the first solenoid valve 13 to the time when the gas analyzer measures a stable concentration value; T2 can be determined by calculating the time it takes for the pure gas to be transmitted to the gas analyzer after the opening of the second solenoid valve 14, so as to minimize the time the sensor is exposed to the polluted gas while measuring accurate values. A two-stage intermittent time T3 measurement mode is adopted. According to previous experimental experience, since the polluted gas penetration moment is generally in the first three hours of the polluted gas measurement, the pollutant concentration changes relatively quickly at the penetration moment. Therefore, for the accuracy of the data, we choose a shorter measurement interval; since the pollutant concentration change curve is relatively flat after three hours, we choose a longer measurement interval to avoid continuous damage to the instrument by pollutants. A complete test cycle is T1+T2+T3. This strategy takes into account both the accurate determination of the components of the mixed gas and the intermittent protection of the instrument.

[0039] Optionally, the inlet of the first solenoid valve 13 is connected to the second three-way valve 15, and the outlet of the first solenoid valve 13 is connected to the third three-way valve 16; the inlet of the second solenoid valve 14 is connected to the air generator, and the outlet of the second solenoid valve 14 is connected to the third three-way valve 16; the first solenoid valve 13 and the second solenoid valve 14 are each connected to a time relay 12, and the two time relays 12 control the first solenoid valve 13 and the second solenoid valve 14 respectively.

[0040] Specifically, the inlet of the second three-way valve 15 is connected to the fixed reactor bed, and the outlet is connected to the first solenoid valve 13 and the tail gas absorption bottle 18, respectively. When the first solenoid valve 13 is open, some impurity gases pass through the first solenoid valve 13 and enter the gas analyzer. When the first solenoid valve 13 is closed, the impurity gases bypass the first solenoid valve 13 and enter the tail gas absorption bottle 18 directly. The first solenoid valve 13 is controlled by the time relay 12, with the inlet connected to the second three-way valve 15 and the outlet connected to the third three-way valve 16.

[0041] Optionally, when the multi-component gas analyzer 17 needs to be purged, the first solenoid valve 13 is closed and the second solenoid valve 14 is opened to pass pure air into the multi-component gas analyzer 17; the opening time of the second solenoid valve 14 is synchronized with the closing time of the first solenoid valve 13.

[0042] Optionally, the tail gas absorption bottle 18 is filled with an acid solution or an alkaline solution and an acid-base indicator. Acid solution or alkaline solution is selected for neutralization according to the acidity or alkalinity of the impurity gas, and whether the acid solution or alkaline solution is ineffective is judged according to the color of the acid-base indicator.

[0043] Specifically, the color of the acid-base indicator can be used to determine whether the acid-base solution is invalid, so that it can be replaced in time.

[0044] Example 2

[0045] The system of the invention was used to conduct flow adsorption tests with activated carbon as adsorbent material 7 at different flow rates of SO2 polluted gas, and the penetration curves of activated carbon to pollutants at different gas flow rates were obtained. The results are as follows: Figure 2 As shown in the figure, the flow adsorption test of activated carbon at different fixed bed heights was carried out, and the penetration curve of activated carbon to pollutants at different fixed bed heights was obtained. The results are shown in the figure. Figure 3 As shown; the flow adsorption test of activated carbon on pollutants under different pollutant gas concentrations was carried out to obtain the unit adsorption capacity of activated carbon on pollutant gases under different gas concentrations. The results are shown as follows Figure 4 As shown;

[0046] The invention system was used to test the penetration performance, unit adsorption capacity and adsorption efficiency of different types of activated carbon adsorbents for the same impurity gas. The results are as follows: Figure 5-7 As shown, the performance of different activated carbons can be compared and screened based on the results to select the appropriate adsorbent material7.

[0047] Figure 2Under operating conditions of a pollutant gas concentration of 30 ppm, activated carbon was subjected to pollutant gas adsorption experiments at 3 L / min, 4 L / min, 5 L / min, and 6 L / min. As can be seen in the figure, as the gas flow rate increases from 3 L / min to 6 L / min, the adsorption equilibrium time of the pollutant gas decreases significantly, and the breakthrough curve gradually becomes steeper. In particular, the breakthrough curve suddenly steepens from 4 L / min to 6 L / min. At a flow rate of 6 L / min, the activated carbon's adsorption equilibrium time and breakthrough time are the shortest compared to other flow rates, and the second-stage curve is the steepest, rising in a linear relationship. As the flow rate decreases from 6 L / min to 3 L / min, the activated carbon's adsorption equilibrium time increases significantly, and the breakthrough time also increases significantly. Therefore, for fuel cell air filters, the design of the air filter needs to be determined based on the required gas flow rate of the fuel cell and the adsorbent material's SO2 filtration capacity.

[0048] Figure 3 The figure shows the effect of different fixed bed heights on the penetration curve of activated carbon adsorption of SO2. It can be seen from the figure that as the fixed bed height increases from 20mm to 50mm, the adsorption equilibrium time of SO2 increases significantly with the increase of the fixed bed height, and the penetration curve also becomes flatter, indicating that the entire complete adsorption process lasts longer. As the fixed bed height increases, the adsorption equilibrium time and penetration time of activated carbon increase, indicating that increasing the height of the fixed bed can improve the adsorption capacity of activated carbon for SO2 gas. However, if the fixed bed height is too large, the volume of the fixed bed reactor 8 will also increase during the actual gas adsorption process, increasing the pressure difference between the inlet and outlet of the fixed bed and causing higher flow resistance, thereby increasing the operating cost of the fuel cell system and increasing the volume of the fuel cell system. However, if the fixed bed height is too small, the adsorption performance of the activated carbon will decrease and the life of the fuel cell will be shortened. Therefore, a comprehensive consideration should be given to and a reasonable fixed bed height should be selected.

[0049] from Figure 4 As can be seen from the figure, as gas concentration increases, the specific adsorption capacity of activated carbon also increases. Generally speaking, appropriately increasing the pollutant gas concentration is beneficial to improving the adsorption performance of activated carbon. However, the integration with the fuel cell should also be considered. Exploring the impact of excessively high pollutant gas concentrations on fuel cell air filters is of little reference value, so it is important to select an appropriate pollutant gas concentration.

[0050] from Figure 5As can be seen from the data, all four activated carbon samples completely adsorbed SO2 gas in the initial adsorption phase. Over time, the active sites on the activated carbon surface were occupied by SO2 gas, and the fixed bed began to penetrate. The SO2 penetration time, total adsorption time, and change trends of the four activated carbon samples were analyzed, allowing for comparison of performance parameters of the different activated carbon samples. Selecting air filter adsorption materials with excellent adsorption performance can effectively extend the life of fuel cells.

[0051] from Figure 6 It can be seen that the unit adsorption capacity increases rapidly in the initial stage, and the curve is also the steepest. After that, the increase in the unit adsorption capacity of activated carbon is relatively slow until it reaches equilibrium.

[0052] A new method for estimating the service life of fuel cell air filter element is proposed. Figure 7 As shown, taking a fuel cell vehicle running in an actual environment with an air concentration of 1ppm SO2 as an example, its acceptable SO2 concentration threshold is 0.2ppm after the initial poisoning test. It is assumed that the breakthrough curve and the unit adsorption curve have similar shapes under different pollutant concentrations. The unit adsorption at the breakthrough moment under 1ppm pollutants is m1 mg / g, and the saturated unit adsorption is m2 mg / g. In this test system, the unit adsorption at the breakthrough moment under a high concentration of 30ppm pollutants is 10mg / g, and the saturated unit adsorption is 20mg / g. According to Figure 4 The values ​​of m1 and m2 are obtained by fitting the unit adsorption data under different pollutant concentrations shown. t1 and t2 are the breakthrough moment and saturated adsorption moment at high concentrations obtained by this test system. Before the breakthrough moment, the pollutant gas is completely adsorbed. Therefore, the breakthrough moment t1* under low concentrations in the actual environment can be calculated based on m1 and the pollutant concentration and flow rate, and the saturated adsorption moment t2* can be calculated by t2*=t2×t1* / t1. The adsorption time t3* (i.e., service life) at the concentration threshold of 0.2ppm can be obtained by drawing two thick dotted auxiliary lines, as shown in the figure. Figure 7 This method can effectively guide the replacement time of fuel cell air filters in actual use.

[0053] The working principle and beneficial effects of the present invention are:

[0054] By using flow controllers 2 with different ranges for matching, precise concentrations of single or mixed air impurity gases are obtained. The system also has multiple gas analysis capabilities, enabling testing of the fuel cell air filter's penetration curve, unit adsorption capacity, and pressure drop, as well as accurate control of gas flow, impurity concentration, temperature, and humidity. The matching air supply system includes a saturated steam supply to achieve humidity control for studying air impurity gas filtration tests at different humidity levels. The vibration test bench 9 can control the excitation frequency and amplitude of the fixed-bed reactor 8, simulating the effects of vibration on the air filter's adsorption characteristics under actual road conditions of fuel cell vehicles. Based on high-concentration pollutant gas flow adsorption data, the service life of a fuel cell air filter operating under actual low-concentration pollutant gas conditions can be estimated, effectively guiding the replacement of air filter elements.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multifunctional fuel cell cathode impurity gas filtration test system, characterized in that: include: A gas supply system, a fixed bed reaction system, and a gas analysis system, wherein the fixed bed reaction system is provided with a temperature and vibration control system, and the gas supply system, the fixed bed reaction system, and the gas analysis system are sequentially connected via a gas pipeline; A pressure difference sensor (5) is connected between the gas supply system and the fixed bed reaction system, and a pressure difference sensor (5) is connected between the fixed bed reaction system and the gas analysis system; The tail of the gas analysis system is connected to a tail gas absorption bottle (18).

2. A multifunctional fuel cell cathode impurity gas filtration test system according to claim 1, characterized in that: include: The fixed bed reaction system comprises a main body, an end cover, a quick-insert interface, a raw material belt, a steel mesh (6), an adsorbent material (7), and a cylindrical fixed bed reactor (8); The end covers are installed on both sides of the fixed bed reactor (8), and the end covers are fastened and sealed by the raw tape; The quick-connect interface is installed at the outermost side of the fixed bed reaction system, and the quick-connect interface is used to connect to the air intake and exhaust pipes; The steel mesh (6) is installed on both sides of the interior of the fixed bed reactor (8).

3. The multifunctional fuel cell cathode impurity gas filtration test system according to claim 1, characterized in that: include: The gas supply system comprises an air generator, an impurity gas bottle, a steam generator, a two-way valve (1), a polytetrafluoroethylene tube, a flow controller (2), a four-way valve (3) and a first three-way valve (4); The impurity gas bottle contains at least one impurity gas; The steam generator is used to provide water vapor to provide a set humidity for the mixed gas; The four-way valve (3) and the first three-way valve (4) collect gases of different components and lead them to the fixed bed reaction system; The air generator includes an air compressor, a silica gel particle filter, a valve and a pressure-surge tank, wherein the silica gel particle filter is used to filter impurities in the air; The outlet of the air generator outputs pressurized pure air.

4. A multifunctional fuel cell cathode impurity gas filtration test system according to claim 3, characterized in that: include: The two-way valve (1) is connected to the air inlet and the flow controller (2) and is used to open and close different air paths to control the types of impurity gases; The flow controller (2) is used to adjust the ratio of different types of impurity gases, water vapor and air according to requirements to obtain a single impurity gas or a multi-impurity mixed gas with a precise concentration; According to different impurity gas requirements, the flow controller (2) of different ranges is replaced.

5. The multifunctional fuel cell cathode impurity gas filtration test system according to claim 1, characterized in that: include: The temperature and vibration control system includes a temperature control box (11), a temperature sensor (10) and a vibration test bench (9); The fixed bed reactor (8) is completely placed in the temperature control box (11), and the temperature sensor (10) is arranged at the inlet and outlet of the fixed bed reactor (8); The fixed bed reactor (8) is arranged on a vibration test bench (9) in the temperature control box (11), and the vibration test bench (9) is used to excite transverse and longitudinal waves with controllable frequencies and amplitudes to simulate vibrations of actual road conditions.

6. The multifunctional fuel cell cathode impurity gas filtration test system according to claim 1, characterized in that: include: The differential pressure sensor (5) is used to collect the differential pressure; The differential pressure sensor (5) of different ranges is replaced according to needs.

7. The multifunctional fuel cell cathode impurity gas filtration test system according to claim 1, characterized in that: include: The gas analysis system comprises a second three-way valve (15), a third three-way valve (16), a time relay (12), a first solenoid valve (13), a second solenoid valve (14) and a multi-component gas analyzer (17); The inlet of the second three-way valve (15) is connected to the fixed bed reaction system, and the outlet is connected to the first solenoid valve (13) and the tail gas absorption bottle (18) respectively; The inlet of the multi-component gas analyzer (17) is connected to the third three-way valve (16), and the outlet of the multi-component gas analyzer (17) is connected to the tail gas absorption bottle (18).

8. The multifunctional fuel cell cathode impurity gas filtration test system according to claim 7, characterized in that: include: The inlet of the first solenoid valve (13) is connected to the second three-way valve (15), and the outlet of the first solenoid valve (13) is connected to the third three-way valve (16); The inlet of the second solenoid valve (14) is connected to the air generator, and the outlet of the second solenoid valve (14) is connected to the third three-way valve (16); The first solenoid valve (13) and the second solenoid valve (14) are each connected to a time relay (12), and the two time relays (12) control the first solenoid valve (13) and the second solenoid valve (14) respectively.

9. The multifunctional fuel cell cathode impurity gas filtration test system according to claim 7, characterized in that: include: When the multi-component gas analyzer (17) needs to be purged, the first solenoid valve (13) is closed, and the second solenoid valve (14) is opened to allow pure air to flow into the multi-component gas analyzer (17); The opening moment of the second solenoid valve (14) is synchronized with the closing moment of the first solenoid valve (13).

10. The multifunctional fuel cell cathode impurity gas filtration test system according to claim 1, characterized in that: include: The tail gas absorption bottle (18) contains an acid solution or an alkaline solution and an acid-base indicator. The acid solution or the alkaline solution is selected for neutralization according to the acidity or alkalinity of the impurity gas, and whether the acid solution or the alkaline solution is ineffective is judged according to the color of the acid-base indicator.

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