Hydrogen purification system and control method thereof

Abstract

The present disclosure provides a hydrogen purification system including a hydrogen purification module, a control unit, and a pressure control unit, the control unit being coupled to the pressure control unit, and the pressure control unit being connected to an anode gas outflow path of the hydrogen purification module, where the control method includes the following steps. First, a mixed gas including hydrogen is provided to the hydrogen purification module. Then, power is supplied to the hydrogen purification module to perform an oxidation-reduction reaction of hydrogen. Then, the pressure of the anode in the hydrogen purification module is instantaneously increased and decreased by using a pressure control unit, and the control unit controls the opening and closing of the pressure control unit. And the instantaneous pressure rise amount of the anode in the hydrogen purification module is greater than or equal to 0.04 bar.

Description

Technical Field

[0001] The present disclosure relates to a hydrogen purification system and a control method thereof. Background Art

[0002] When performing an electrochemical reaction to separate or purify hydrogen in a mixed gas using a hydrogen purification module, the remaining gas in the mixed gas that does not participate in the electrochemical reaction easily stays in the flow channel of the anode; or the water vapor in the humidified mixed gas may condense in the flow channel of the anode, both of which increase the hindrance of hydrogen in the mixed gas diffusing to the porous carbon electrode and / or reduce the reaction positions on the porous carbon electrode, thereby affecting the efficiency of the oxidation reaction of hydrogen in the anode and causing the efficiency of the hydrogen purification module to purify hydrogen to decrease accordingly. Summary of the Invention

[0003] The present disclosure provides a control method for a hydrogen purification system, which can improve the efficiency of the hydrogen purification module in purifying hydrogen.

[0004] In the control method of the hydrogen purification system according to an embodiment of the present disclosure, the hydrogen purification system includes a hydrogen purification module, a control unit, and a pressure control unit. The control unit is coupled to the pressure control unit, and the pressure control unit is connected to the anode gas outflow path of the hydrogen purification module. The control method includes the following steps. First, a mixed gas including hydrogen is provided to the hydrogen purification module. Then, electric power is provided to the hydrogen purification module to perform an oxidation-reduction reaction of hydrogen. After that, the pressure control unit is used to instantaneously increase and decrease the pressure of the anode in the hydrogen purification module, where the control unit controls the opening and closing of the pressure control unit. The instantaneous pressure increase amount of the anode in the hydrogen purification module is greater than or equal to 0.04 bar.

[0005] The present disclosure provides a hydrogen purification system, which can improve the efficiency of purifying hydrogen.

[0006] An embodiment of the hydrogen purification system of the present disclosure includes a hydrogen purification module, a pressure control unit, and a control unit. The hydrogen purification module includes a plurality of membrane electrode assemblies, and one of the plurality of membrane electrode assemblies includes an anode, a cathode, and a proton exchange membrane. The pressure control unit is connected to the anode gas outflow path of the hydrogen purification module and can instantaneously increase and decrease the pressure of the anode in the hydrogen purification module. When the pressure of the anode in the hydrogen purification module instantaneously increases, the instantaneous pressure increase amount of the anode is greater than or equal to 0.04 bar. The control unit is coupled to the pressure control unit, and the control unit can be used to control the operation of the pressure control unit.

[0007] Based on the above, the present disclosure provides a control method for a hydrogen purification system and a hydrogen purification module. When operating the hydrogen purification module, the pressure of the anode in the hydrogen purification module is instantaneously increased and decreased by using a pressure control unit, wherein the opening and closing of the pressure control unit are controlled by a control unit, which can remove at least part of the remaining gas and / or water vapor retained in the flow channel of the anode, so that the efficiency of the hydrogen purification module in purifying hydrogen can be improved. Description of the Drawings

[0008] Figure 1 It is a schematic diagram of a hydrogen purification system according to an embodiment of the present disclosure.

[0009] Figure 2 It is a flowchart of a control method for a hydrogen purification system according to an embodiment of the present disclosure.

[0010] Figure 3A It is a graph showing the relationship between the pressure of the anode and time when operating the hydrogen purification module of Example 1.

[0011] Figure 3B It is a graph showing the relationship between the pressure of the anode and time when operating the hydrogen purification module of Comparative Example 1.

[0012] Figure 4A It is a graph showing the relationship between the reaction current of the hydrogen purification module and time when operating the hydrogen purification module of Example 1.

[0013] Figure 4B It is a graph showing the relationship between the reaction current of the hydrogen purification module and time when operating the hydrogen purification module of Comparative Example 1.

[0014] Figure 5 It is a graph showing the relationship between the voltage of each membrane electrode assembly in the hydrogen purification module and time when operating the hydrogen purification module of Example 1.

[0015] Figure 6A It is a graph showing the relationship between the pressure of the anode and time when operating the hydrogen purification modules of Example 1, Example 5 and Example 6 respectively.

[0016] Figure 6B It is a graph showing the relationship between the reaction current of the hydrogen purification module and time when operating the hydrogen purification modules of Example 1, Example 5 and Example 6 respectively. Detailed Description of the Embodiments

[0017] Reference will now be made in detail to the exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals will be used in the drawings and the description to refer to the same or like parts.

[0018] The present disclosure can be understood by referring to the following detailed description in conjunction with the accompanying drawings. It should be noted that for the convenience of the reader's understanding and the simplicity of the drawings, only a part of the electronic device is shown in the multiple drawings of the present disclosure, and the specific components in the drawings are not drawn to actual scale. In addition, the number and size of each component in the drawings are only for illustration and are not used to limit the scope of the present disclosure.

[0019] The directional terms mentioned in the present disclosure, such as "upper", "lower", "front", "rear", "left", "right", etc., are only with reference to the directions of the accompanying drawings. Therefore, the directional terms used are for explanation and not for limiting the present disclosure. In the drawings, each drawing shows the general characteristics of the methods, structures, and / or materials used in specific embodiments. However, these drawings should not be construed as defining or limiting the scope or nature covered by these embodiments. For example, for clarity, the relative dimensions, thicknesses, and positions of each film layer, region, and / or structure may be reduced or enlarged.

[0020] The terms "about", "equal to", "equivalent", or "the same", "substantially" or "approximately" are generally interpreted as within 20% of the given value or range, or within 10%, 5%, 3%, 2%, 1%, or 0.5% of the given value or range.

[0021] It should be noted that, without departing from the spirit of the present disclosure, the features in several different embodiments can be replaced, reorganized, and mixed to complete other embodiments in the following exemplary embodiments. As long as the features between the embodiments do not violate the inventive spirit or conflict with each other, they can be arbitrarily mixed and used.

[0022] The following are exemplary embodiments of the present disclosure. The same reference numerals are used in the drawings and the description to represent the same or similar parts.

[0023] Figure 1 It is a schematic diagram of a hydrogen purification system according to an embodiment of the present disclosure.

[0024] Please refer to Figure 1 , in some embodiments, the hydrogen purification system 10 of the present embodiment may include a hydrogen purification module 100, an anode gas inlet path A1, an anode gas outlet path A2, a cathode gas outlet path C, a heat exchange medium inlet path H1, a heat exchange medium outlet path H2, a power supply unit 200, an electrical measurement unit 300, a control unit 400, and a pressure control unit 500. However, the components included in the hydrogen purification system 10 of the present disclosure are not limited thereto.

[0025] In some embodiments, the hydrogen purification system 10 may further include a humidifier (not shown). The humidifier is connected to, for example, the anode gas inflow path A1 to humidify, for example, the mixed gas MG before it flows into the hydrogen purification module 100, but the present disclosure is not limited thereto.

[0026] The hydrogen purification module 100 may be, for example, an electrochemical hydrogen purification (EHP) stack. For example, after receiving the mixed gas MG containing hydrogen on one side, the hydrogen purification module 100 can separate and transport the hydrogen in the mixed gas MG to the other side for collection via an electrochemical reaction, while the remaining gas RG in the mixed gas MG is discharged outside the hydrogen purification module 100 to, for example, achieve the purification of hydrogen. Specifically, the hydrogen purification module 100 may include, for example, a plurality of membrane electrode assemblies 110, and each membrane electrode assembly 110 can be regarded as a reaction unit. One of the plurality of membrane electrode assemblies 110 may include, for example, a proton exchange membrane, an anode, and a cathode. In some embodiments, the plurality of unit membrane electrode assemblies 110 may be connected in series and stacked with each other, or the plurality of unit membrane electrode assemblies 110 may be connected in parallel with each other to form the hydrogen purification module 100, but the present disclosure is not limited thereto.

[0027] The proton exchange membrane is disposed, for example, between the anode and the cathode, and it can be used to inhibit the flow of electrons or impurities and / or contaminants (such as from the mixed gas MG) between the anode and the cathode without hindering the penetration of protons as charge carriers. In some embodiments, the proton exchange membrane may include a polymer material, which may include hydrocarbon-based polymers, fluorine-containing polymers, or other suitable polymers or combinations thereof, and the present disclosure is not limited thereto.

[0028] In this embodiment, the anode is coupled to the anode gas inflow path A1 to receive the mixed gas MG containing hydrogen from the anode inflow path A1. Based on this, when operating the hydrogen purification module 100, the hydrogen in the mixed gas MG can be oxidized at the anode to generate protons and electrons. The anode may include, for example, a porous carbon electrode and may also include a catalyst (such as platinum) to accelerate the oxidation reaction of hydrogen, but the present disclosure is not limited thereto. In some embodiments, the anode may include an anode bipolar plate having a flow channel for the mixed gas MG to flow through. Additionally, in some embodiments, the anode may further include an anode porous diffusion plate, which can, for example, guide the mixed gas MG to the porous carbon electrode. In this embodiment, when operating the hydrogen purification module 100, the oxidation reaction in the anode can be represented by the following formula: H 2 →2H + +2e - .

[0029] In some embodiments, the mixed gas MG may include nitrogen, carbon dioxide, carbon monoxide, other gases, or a combination thereof in addition to hydrogen, but the present disclosure is not limited thereto. In the present embodiment, the mixed gas MG includes hydrogen and nitrogen. In some embodiments, the volume ratio of hydrogen to nitrogen is from 90:10 to 50:50. For example, the volume ratio of hydrogen to nitrogen may be 81.8:18.2, 70:30, 60:40, or 50:50.

[0030] In addition, in the present embodiment, the anode is also coupled to the anode gas outflow path A2 to discharge the remaining gas RG after operating the hydrogen purification module 100 from the hydrogen purification module 100 to the outside. The remaining gas RG may include, for example, nitrogen, carbon dioxide, carbon monoxide, other gases, or a combination thereof, and the present disclosure is not limited thereto.

[0031] In the present embodiment, the cathode is coupled to the cathode gas outflow path C to transfer the hydrogen HG generated at the cathode to the outside for collection through the cathode gas outflow path C, which may be transferred, for example, to a hydrogen storage unit (not shown), but the present disclosure is not limited thereto. Specifically, protons generated by hydrogen oxidation in the anode may, for example, pass through the proton exchange membrane and be reduced to hydrogen in the cathode. In some embodiments, the hydrogen generated at the cathode may be compressed, but the present disclosure is not limited thereto. The cathode may also include, for example, a porous carbon electrode and may further include a catalyst (such as platinum) to accelerate the hydrogen reduction reaction, but the present disclosure is not limited thereto. In some embodiments, the cathode may include a cathode bipolar plate having a flow channel for the hydrogen HG to flow through. In addition, in some embodiments, the cathode may further include a cathode porous diffusion plate, which may, for example, guide the hydrogen HG to the cathode bipolar plate. In the present embodiment, when the hydrogen purification module 100 is operated, the reduction reaction in the cathode may be represented by the following formula: 2H + + 2e - → H 2 .

[0032] In some embodiments, the hydrogen purification system 10 may further include a heat exchange medium inflow path H1 and a heat exchange medium outflow path H2. The heat exchange medium inflow path H1 and the heat exchange medium outflow path H2 are each coupled to the hydrogen purification module 100, for example. The heat exchange medium may flow into the hydrogen purification module 100 from the heat exchange medium inflow path H1 and flow out to the heat exchange medium outflow path H2 through the flow channels formed between the anode bipolar plate and the cathode bipolar plate in the hydrogen purification module 100. In some embodiments, the hydrogen purification system 10 may further include a heat exchange medium unit (not shown), and the heat exchange medium unit, the heat exchange medium inflow path H1, the flow channels in the hydrogen purification module 100, and the heat exchange medium outflow path H2 may form a closed circulation path, but the present disclosure is not limited thereto. The heat exchange medium provided by the heat exchange medium unit may, for example, enable the oxidation reaction and reduction reaction of hydrogen in the hydrogen purification module 100 to proceed at an appropriate temperature, so as to improve the efficiency of purifying hydrogen. In some embodiments, the heat exchange medium unit may include a water circulation pump, and the heat exchange medium may include water, but the present disclosure is not limited thereto.

[0033] The power supply unit 200 is coupled to the anode and the cathode of the hydrogen purification module 100, for example. In the present embodiment, the power supply unit 200 may be electrically connected to the anode and the cathode through a positive power line PL and a negative power line NL, respectively, but the present disclosure is not limited thereto. The power supply unit 200 may include any suitable power supply element, for example. For example, the power supply unit 200 may include a power supply source (not shown) and a power conversion unit (not shown). The power supply source may be used to supply power to the hydrogen purification module 100 for the oxidation-reduction reaction of hydrogen, and the power conversion unit may include, for example, a DC-AC converter, an AC-DC converter, or a DC-DC converter, for example, to convert the power from the power supply source, but the present disclosure is not limited thereto.

[0034] The electrical property measurement unit 300 is coupled to the power supply unit 200, for example. In the present embodiment, the electrical property measurement unit 300 includes a current measurement unit 310 and a voltage measurement unit 320. The current measurement unit 310 may be used to measure the total current of a plurality of membrane electrode assemblies 110 when operating the hydrogen purification module 100, and the voltage measurement unit 320 may be used to measure the voltage of each membrane electrode assembly 110 when operating the hydrogen purification module 100. In some embodiments, the current measurement unit 310 and the voltage measurement unit 320 may each include a suitable current measurement element and voltage measurement element, and the present disclosure is not limited thereto.

[0035] The control unit 400 is coupled to, for example, the electrical measurement unit 300 and the pressure control unit 500. In the present embodiment, the control unit 400 includes a programmable logic controller (PLC). Specifically, the control unit 400 may, for example, include a processing unit, a memory unit, and an input / output unit, but the present disclosure is not limited thereto. The processing unit may be used to process signals provided by the electrical measurement unit 300 (i.e., the current value measured by the current measurement unit 310 and the voltage value of the voltage measurement unit 320 when the hydrogen purification module 100 is operated), and generate corresponding control signals to the control unit 400 based on these signals, so as to, for example, determine the subsequent operation mode of the hydrogen purification module 100. The memory unit may be used to store the above signals provided by the electrical measurement unit 300 and / or the signals processed by the processing unit. The input / output units may each receive the above signals provided by the electrical measurement unit 300 and output the control signals generated by the processing unit. In the present embodiment, the control unit 400 may determine whether the total current of the plurality of membrane electrode assemblies 110 is lower than a preset current value and / or whether the voltage in at least one of the membrane electrode assemblies 110 is higher than a preset voltage value. Specifically, the preset current value of the plurality of membrane electrode assemblies 110 may be stored in the memory unit of the control unit 400, and it can be determined by comparing the current value measured by the current measurement unit 310 with the preset current value of the plurality of membrane electrode assemblies 110. Similarly, the preset voltage value of the membrane electrode assembly 110 may be stored in the memory unit of the control unit 400, and it can be determined by comparing the voltage value measured by the voltage measurement unit 320 with the preset voltage value of the plurality of membrane electrode assemblies 110.

[0036] In some embodiments, the hydrogen purification system 10 may further include a control logic unit (not shown), where the control logic unit may be disposed inside or outside the control unit 400. When the control logic unit is disposed outside the control unit 400, it may be coupled to the control unit 400 and the pressure control unit 500. The control unit 400 may control the pressure control unit 500 through the control logic unit, for example, so that the pressure control unit 500 can perform corresponding operations.

[0037] The pressure control unit 500 is connected to, for example, the anode gas outflow path A2. For example, the pressure control unit 500 can be disposed in the anode gas outflow path A2 to control and improve the environment of the anodes of the plurality of membrane electrode assemblies 110 in the hydrogen purification module 100. Specifically, the environment of the anodes of the membrane electrode assemblies 110 can be as follows. For example, when the hydrogen purification module 100 is operating, the remaining gas RG that does not participate in the oxidation reaction occurring in the porous carbon electrode of the anode may be trapped in the flow channels in the anode bipolar plate, which increases the hindrance to the diffusion of hydrogen in the mixed gas MG entering through the anode gas inflow path A1 to the porous carbon electrode and / or reduces the reaction sites on the porous carbon electrode, thereby affecting the efficiency of the oxidation reaction of hydrogen in the anode. Alternatively, when the hydrogen purification module 100 is operating, the water vapor in the humidified mixed gas MG may condense and block the flow channels in the anode bipolar plate, which also increases the hindrance to the diffusion of hydrogen in the mixed gas MG entering through the anode gas inflow path A1 to the porous carbon electrode, thereby affecting the efficiency of the oxidation reaction of hydrogen in the anode.

[0038] To solve the above problems that occur during the operation of the hydrogen purification module 100, in this embodiment, the control unit 400 is coupled to the pressure control unit 500, and the control unit 400 is used to control the opening and closing of the pressure control unit 500 to improve the environment of the anodes of the plurality of membrane electrode assemblies 110.

[0039] Specifically, in this embodiment, the pressure control unit 500 is disposed in the anode gas outflow path A2, and the pressure control unit 500 includes a pressure control element 510 and a pressure sensing element 520. The pressure control unit 500 can, for example, receive a signal from the control unit 400 to control the pressure of the anode in the hydrogen purification module 100. For example, the pressure control element 510 in the pressure control unit 500 can be opened according to the signal of the control unit 400 to reduce the flow rate of the remaining gas RG flowing out through the anode gas outflow path A2, thereby causing the pressure on the anode gas outlet side in the hydrogen purification module 100 to rise instantaneously. And the pressure sensing element 520 in the pressure control unit 500 can provide the pressure information sensed from the anode gas outlet side in the hydrogen purification module 100 to the control unit 400, thereby enabling the monitoring of the pressure on the anode gas outlet side in the hydrogen purification module 100. Specifically, after the pressure on the anode gas outlet side in the hydrogen purification module 100 rises instantaneously, the pressure control unit 500 can feedback the information of this pressure rise to the control unit 400, so that the control unit 400 issues a signal to reduce the pressure of the anode in the hydrogen purification module 100 to the original pressure, and the pressure control element 510 in the pressure control unit 500 can be closed according to this signal of the control unit 400. In some embodiments, the pressure control element 510 can include a tapered tube, a control valve, or other suitable pressure control elements, and the present disclosure is not limited thereto.

[0040] Based on this, when the flow channels in the anode bipolar plate are blocked due to the retention of the remaining gas RG and / or the condensation of water vapor, the current and / or voltage in the membrane electrode assembly 110 in the hydrogen purification module 100 will change, where the total current in the plurality of membrane electrode assemblies 110 will be lower than a preset current value and / or the voltage in at least one membrane electrode assembly 110 will be higher than a preset voltage value. When the electrical measurement unit 300 measures the information of the above-changed current value and / or voltage value, the control unit 400 can respond to this control signal to control the pressure control unit 500, so that the pressure control element 510 in the pressure control unit 500 operates to reduce the flow rate of the remaining gas RG flowing out through the anode gas outflow path A2, thereby causing the pressure on the anode gas outlet side in the hydrogen purification module 100 to rise instantaneously, whereby at least part of the remaining gas RG and / or water vapor retained in the flow channels can be removed, and the efficiency of the hydrogen purification module 100 in purifying hydrogen can be improved. In addition, the pressure control unit 500 can subsequently feedback the information of this pressure rise to the control unit 400, so that the control unit 400 issues a signal to reduce the pressure on the anode gas outlet side in the hydrogen purification module 100 to the original pressure, and the pressure control element 510 in the pressure control unit 500 can receive this control signal of the control unit 400 and close, so that the pressure on the anode gas outlet side in the hydrogen purification module 100 drops to the original pressure.

[0041] Figure 2 The flowchart of the control method for the hydrogen purification system according to an embodiment of the present disclosure. It should be noted that Figure 2 The described hydrogen purification module takes the above-mentioned hydrogen purification system 10 as an example, but it should be noted that the present disclosure is not limited thereto.

[0042] Please refer to Figure 2 , the control method for the hydrogen purification system of this embodiment includes the following steps.

[0043] First, in step S10, a mixed gas MG including hydrogen is provided to the hydrogen purification module 100. The mixed gas MG can be provided to a plurality of membrane electrode assemblies 110 in the hydrogen purification module 100, for example, through an anode gas inflow path A1 connected to the hydrogen purification module 100, and can include, for example, hydrogen and other gases other than hydrogen, where the other gases can include nitrogen, carbon dioxide, carbon monoxide, other gases, or a combination thereof. The present disclosure is not limited thereto. The components included in the hydrogen purification module 100 and their functions can be referred to the above embodiment and will not be elaborated here.

[0044] It should be noted that before performing step S10, each component in the hydrogen purification system 10 can be sequentially turned on to complete the standby preparation work before operating the hydrogen purification module 100. Additionally, in some embodiments, the heat exchange medium unit can be started to regulate the temperature of the hydrogen purification module 100, thereby improving the oxidation-reduction reaction efficiency of hydrogen.

[0045] After that, in step S20, power is provided to the hydrogen purification module 100 to perform the oxidation-reduction reaction of hydrogen. In this embodiment, the hydrogen purification system 10 further includes a power supply unit 200, so power can be provided to a plurality of membrane electrode assemblies 110 in the hydrogen purification module 100 through the power supply unit 200. The components included in the power supply unit 200 and their functions can be referred to the above embodiment and will not be elaborated here.

[0046] It should be noted that in step S20, the oxidation reaction of hydrogen occurs at the anode of the hydrogen purification module 100, and the reduction reaction of hydrogen occurs at the cathode of the hydrogen purification module 100, and the remaining gas RG in the mixed gas MG can be discharged from the anode gas outflow path A2 connected to the hydrogen purification module 100 to achieve the effect of purifying hydrogen. The detailed content can be referred to the above embodiment and will not be elaborated here.

[0047] Next, in step S30, the current and / or voltage in the membrane electrode assembly 110 in the hydrogen purification module 100 is measured. In this embodiment, the hydrogen purification system 10 further includes an electrical measurement unit 300, so the current and / or voltage in the membrane electrode assembly 110 in the hydrogen purification module 100 can be measured by the electrical measurement unit 300. The components included in the electrical measurement unit 300 and their functions can be referred to the above embodiments and will not be elaborated here.

[0048] Then, in step S40, it is determined whether at least one of the following situations occurs: (1) the total current in the plurality of membrane electrode assemblies 110 is lower than a preset current value; (2) the voltage in at least one membrane electrode assembly 110 is higher than a preset voltage value.

[0049] In this embodiment, the hydrogen purification system 10 further includes a control unit 400, so the control unit 400 can determine whether the total current in the plurality of membrane electrode assemblies 110 is lower than the preset current value and determine whether the voltage in at least one membrane electrode assembly 110 is higher than the preset voltage value. Specifically, the preset current value of the plurality of membrane electrode assemblies 110 can be stored in the control unit 400, and it can be determined by comparing the total current in the plurality of membrane electrode assemblies 110 measured by the current measurement unit 310 with the preset current value. Similarly, the preset voltage value of the plurality of membrane electrode assemblies 110 can be stored in the control unit 400, and it can be determined by comparing the voltage value measured by the voltage measurement unit 320 with the preset voltage value of the plurality of membrane electrode assemblies 110. The components included in the control unit 400 and their functions can be referred to the above embodiments and will not be elaborated here.

[0050] Then, according to the result of determining whether at least one of the above situations (1) and (2) occurs, it is decided to perform step S50a or step S50b.

[0051] When at least one of the above situations (1) and (2) occurs, step S50a is performed, and the pressure control unit 500 is used to instantaneously increase and decrease the pressure of the anode in the hydrogen purification module 100, wherein the control unit 400 controls the opening and closing of the pressure control unit 500. In this embodiment, the hydrogen purification system 10 further includes a pressure control unit 500, so the flow rate of the remaining gas RG flowing out through the anode gas outflow path A2 can be reduced by operating the pressure control unit 500, thereby instantaneously increasing the pressure of the anode in the hydrogen purification module 100. The components included in the pressure control unit 500 and their functions can be referred to the above embodiments and will not be elaborated here. In some embodiments, the flow rate of the remaining gas RG flowing out through the anode gas outflow path A2 can be reduced by the pressure control unit 500 according to the following situations, but the present disclosure is not limited thereto.

[0052] For example, due to factors such as blockage in the flow channels of the anode bipolar plate caused by the retention of the residual gas RG and / or condensation of water vapor, the current and / or voltage in the membrane electrode assembly 110 in the hydrogen purification module 100 will change. Specifically, the total current in the multiple membrane electrode assemblies 110 will be lower than a preset current value and / or the voltage in at least one membrane electrode assembly 110 will be higher than a preset voltage value. When the total current in the multiple membrane electrode assemblies 110 measured by the electrical measurement unit 300 is lower than the preset current value and / or the voltage in at least one membrane electrode assembly 110 is higher than the preset voltage value, the control unit 400 can provide a control signal based on this information to control the pressure control unit 500, so that the pressure control element 510 in the pressure control unit 500 can reduce the flow rate of the residual gas RG flowing out through the anode gas outlet path A2. Therefore, the pressure of the anode in the hydrogen purification module 100 can be instantly increased, thereby removing at least part of the retained residual gas RG and / or water vapor in the flow channel.

[0053] In some embodiments, the preset current value is 70-95% of the maximum total reaction current of the hydrogen purification module 100, and the preset voltage value is 0.15-0.30V. In this embodiment, the preset current value is 90% of the maximum total reaction current of the hydrogen purification module 100, and the preset voltage value in the membrane electrode assembly 110 is 0.2V.

[0054] In some embodiments, after the pressure control element 510 reduces the flow rate of the residual gas RG flowing out through the anode gas outlet path A2, the pressure of the anode in the hydrogen purification module 100 instantaneously rises, and the controlled rise amount can be greater than or equal to 0.04 bar (lower limit). It should be noted that when the instantaneous rise amount of the anode pressure is less than 0.04 bar (lower limit), it may be difficult to remove at least part of the retained residual gas RG and / or water vapor in the flow channel. In other words, when the instantaneous rise amount of the pressure on the anode gas outlet side reaches 0.04 bar (lower limit) or more, it has the effect of removing at least part of the retained residual gas RG and / or water vapor in the flow channel. The higher the pressure rise amount, the better the effect. For example, greater than 0.08 bar, as long as it does not cause the proton exchange membrane to rupture. For example, the pressure rise amount can be controlled within the range of 0.04 bar to 1.2 bar. When the instantaneous rise amount of the anode pressure is greater than 1.2 bar (upper limit), the proton exchange membrane disposed between the anode and the cathode may be difficult to withstand. It should be noted that the upper limit value of the instantaneous rise amount of the anode pressure can depend on, for example, the type and / or thickness of the material of the proton exchange membrane. For example, when the material of the proton exchange membrane is a fluoropolymer and the thickness is 15 microns, the instantaneous rise amount of the pressure needs to be controlled not to exceed 1.2 bar. Or, when the material of the proton exchange membrane is a fluoropolymer and the thickness is 125 microns, the instantaneous rise amount of the pressure needs to be controlled not to exceed 2.5 bar.

[0055] It should be noted that after the pressure at the anode in the hydrogen purification module 100 instantaneously rises, the pressure sensing element 520 can provide the pressure information sensed from the anode in the hydrogen purification module 100 to the control unit 400. Thereafter, the control unit 400 can provide another control signal to the pressure control unit 500 based on this pressure information, so that the pressure control element 510 in the pressure control unit 500 can restore the flow rate of the remaining gas RG flowing out from the anode gas outflow path A2 to the original flow rate, such that the pressure at the anode in the hydrogen purification module 100 can drop to the original pressure value. Then, multiple cycles of instantaneously rising and then dropping the pressure at the anode in the hydrogen purification module 100 can be repeated, where the interval of each cycle can be 2 to 15 seconds.

[0056] After performing step S50a, then, step S60 is performed to measure the current and / or voltage in the plurality of membrane electrode assemblies 110 in the hydrogen purification module 100, where step S60 can be, for example, the same as or similar to step S30, and will not be elaborated here.

[0057] Thereafter, step S70 is performed to determine whether at least one of the following situations occurs: (1) the total current in the plurality of membrane electrode assemblies 110 is lower than a preset current value; (2) the voltage in at least one membrane electrode assembly 110 is higher than a preset voltage value. Step S70 can be, for example, the same as or similar to step S40, and will not be elaborated here.

[0058] When performing step S70, if at least one of the above situations (1) and situation (2) occurs, then return to step S50a. In contrast, when performing step S70, if neither of the above situations (1) and situation (2) occurs, then step S80 is continued to stop the operation of the pressure control unit 500. Specifically, when the total current in the plurality of membrane electrode assemblies 110 measured by the electrical measurement unit 300 is not lower than the preset current value and the voltage in each membrane electrode assembly 110 is not higher than the preset voltage value, the control unit 400 can provide a control signal to the pressure control unit 500 based on this information to stop the operation of the pressure control element 510 in the pressure control unit 500, such that the flow rate of the remaining gas RG flowing out through the anode gas outflow path A2 no longer has a pulse-like change.

[0059] It should be noted that after performing step S80, it is possible to return to step S30.

[0060] In contrast, after performing step S40, if neither of the above cases (1) and (2) occurs, step S50b is performed, and the pressure of the anode in the hydrogen purification module 100 is instantaneously increased and decreased at intervals by using the pressure control unit 500, where the control unit 400 controls the opening and closing of the pressure control unit 500.

[0061] Specifically, even if there are no significant changes in the current and / or voltage in the membrane electrode assembly 110 in the hydrogen purification module 100, the pressure control element 510 in the pressure control unit 500 of this embodiment can regularly use the pressure control unit 500 to instantaneously increase and decrease the pressure of the anode in the hydrogen purification module 100 to regulate the environment of the anode in the hydrogen purification module 100. In some embodiments, the pressure control element 510 in the pressure control unit 500 instantaneously increases and decreases the pressure of the anode in the hydrogen purification module 100 every 10 to 60 minutes. In this embodiment, the pressure control element 510 in the pressure control unit 500 instantaneously increases and decreases the pressure of the anode in the hydrogen purification module 100 every 10 minutes.

[0062] After performing step S50b, step S80 can be continued to stop the operation of the pressure control unit 500, which can refer to the above embodiments and will not be elaborated here.

[0063] Experimental Example

[0064] The present disclosure will be described below through experimental examples, but these experimental examples are only for illustrative purposes and are not intended to limit the scope of the present disclosure.

[0065] Experimental Example 1: Changing the instantaneous pressure increase amount of the anode in the hydrogen purification module 100

[0066] The hydrogen purification module 100 used in Experimental Example 1 is an electrochemical hydrogen purification (EHP) stack, and the components included therein can refer to the above embodiments and will not be elaborated here. In this Experimental Example 1, the mixed gas MG includes hydrogen and nitrogen, where the volume ratio of hydrogen to nitrogen is 70:30. Additionally, in this experimental example, the operating voltage of the hydrogen purification module 100 is 3.0V, and the maximum total reaction current in the hydrogen purification module 100 is 0.75 A / cm 2 .

[0067] [Embodiment 1]

[0068] In this embodiment, the initial pressure of the anode in the hydrogen purification module 100 is 0.12 bar. Subsequently, the flow rate of the remaining gas RG flowing out from the anode gas outlet path A2 is reduced by the pressure control element 510 in the pressure control unit 500, so that the pressure on the anode gas outlet side in the hydrogen purification module 100 rises. The pressure of the anode in the hydrogen purification module 100 instantaneously increases from 0.12 bar to approximately 0.298 bar, that is, the instantaneous increase in the pressure on the anode gas outlet side is approximately 0.178 bar. Then, the original flow rate of the remaining gas RG flowing out from the anode gas outlet path A2 is restored by the pressure control element 510 in the pressure control unit 500, so that the pressure of the anode in the hydrogen purification module 100 drops back from approximately 0.298 bar to 0.12 bar. In this embodiment, the pressure on the anode gas outlet side in the hydrogen purification module 100 undergoes 15 cycles of instantaneous increase and decrease through the pressure control element 510 in the pressure control unit 500, and the interval between each cycle is 5 seconds.

[0069] [Example 2]

[0070] In this embodiment, it has substantially the same operating conditions as Example 1, and the only difference is that the instantaneous increase in the pressure on the anode gas outlet side is approximately 0.161 bar.

[0071] [Example 3]

[0072] In this embodiment, it has substantially the same operating conditions as Example 1, and the only difference is that the instantaneous increase in the pressure on the anode gas outlet side is approximately 0.125 bar.

[0073] [Example 4]

[0074] In this embodiment, it has substantially the same operating conditions as Example 1, and the only difference is that the instantaneous increase in the pressure on the anode gas outlet side is approximately 0.098 bar.

[0075] [Comparative Example 1]

[0076] In Comparative Example 1, it has substantially the same operating conditions as Example 1, and the only difference is that the instantaneous increase in the pressure on the anode gas outlet side is approximately 0.038 bar.

[0077] The instantaneous increase in the pressure on the anode gas outlet side after the hydrogen purification module 100 of Example 1 and Comparative Example 1 are operated is shown in Figure 3A and Figure 3B Moreover, the increase in the reaction current after the hydrogen purification module 100 of Example 1 and Comparative Example 1 are operated is shown in Figure 4A and Figure 4B respectively.

[0078] From Figure 4A and Figure 4B It can be seen that after 15 cycles of rapid pressure increase and decrease, the reaction current of the hydrogen purification module 100 of Example 1 increased from approximately 86 A to approximately 89 A, while the reaction current of the hydrogen purification module 100 of Comparative Example 1 hardly increased. That is, the hydrogen purification module 100 of Example 1 has a better hydrogen purification efficiency than the hydrogen purification module 100 of Comparative Example 1.

[0079] In addition, the increases in the reaction currents of the hydrogen purification modules 100 of Examples 1 to 4 and Comparative Example 1 after operation are summarized in Table 1 below.

[0080] [Table 1]

[0081]

[0082] As can be seen from Table 1 above, there is a proportional relationship between the rapid pressure increase at the anode gas outlet side of the hydrogen purification module 100 and the increase in the reaction current of the hydrogen purification module 100. Therefore, without overloading the electrolyte membrane disposed between the anode and the cathode, the rapid pressure increase at the anode gas outlet side of the hydrogen purification module 100 can be increased as much as possible, so that the hydrogen purification module 100 can have a better hydrogen purification efficiency.

[0083] In addition, Figure 5 shows the voltage of each membrane electrode assembly 110 in the hydrogen purification module 100 of Example 1 and the change caused by the pressure increase at the anode gas outlet side, where Figure 5 shows the voltage changes of six membrane electrode assemblies (Cell1, Cell 12, Cell 23, Cell 24, Cell 25, Cell 26). From Figure 5 it can be seen that when the polarization degree of the membrane electrode assembly 110 is relatively serious (such as Cell 24 and Cell 25), the operation of increasing the pressure at the anode gas outlet side of the membrane electrode assembly 110 by the pressure control element 510 in the pressure control unit 500 can effectively alleviate the polarization degree, so that the hydrogen purification module 100 of Example 1 can have a better hydrogen purification efficiency.

[0084] Experimental Example 2: Changing the ratio of hydrogen to the remaining gas in the mixed gas MG

[0085] [Example 5]

[0086] In this example, it has substantially the same operating conditions as Example 1, and the difference is only that the volume ratio of hydrogen to nitrogen is 81.8:18.2.

[0087] [Embodiment 6]

[0088] In this embodiment, it has substantially the same operating conditions as Embodiment 1, with the only difference being that the volume ratio of hydrogen to nitrogen is 60:40.

[0089] From Figure 6A and Figure 6B it can be seen that in three cases where the ratio of hydrogen to the remaining gas (nitrogen) in the mixed gas MG is different, the reaction currents respectively possessed by the hydrogen purification modules 100 of Embodiment 1, Embodiment 5, and Embodiment 6 can all increase. That is, the control method of the hydrogen purification module 100 proposed in the present disclosure can be applied to hydrogen and the remaining gas (nitrogen) with different ratios.

[0090] In summary, the present disclosure provides a control method for a hydrogen purification system. When operating the hydrogen purification module, by using a pressure control unit to instantaneously increase and decrease the pressure of the anode in the hydrogen purification module, wherein the control unit can control the opening and closing of the pressure control unit according to the received abnormal signal (for example, (1) the total current in multiple membrane electrode assemblies is lower than a preset current value; or (2) the voltage in at least one membrane electrode assembly is higher than a preset voltage value) or regularly, which can remove at least part of the remaining gas and / or water vapor retained in the flow channel of the anode, so that the efficiency of the hydrogen purification module for purifying hydrogen can be improved.

[0091] 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 foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A control method for a hydrogen purification system, characterized in that: The hydrogen purification system comprises a hydrogen purification module, a control unit and a pressure control unit, wherein the control unit is coupled to the pressure control unit, and the pressure control unit is connected to an anode gas outflow path of the hydrogen purification module, wherein the control method comprises: Providing a mixed gas including hydrogen to the hydrogen purification module; Providing power to the hydrogen purification module to perform a redox reaction of hydrogen; and The pressure of the anode in the hydrogen purification module is instantaneously increased and decreased by using the pressure control unit, wherein the control unit controls the operation of the pressure control unit, The instantaneous pressure rise of the anode in the hydrogen purification module is greater than or equal to 0.04 bar.

2. The control method of the hydrogen purification system according to claim 1, wherein the method of using the pressure control unit to instantly increase and decrease the pressure of the anode in the hydrogen purification module comprises using the pressure control unit to reduce the flow rate of the remaining gas flowing out through the anode gas outflow path so that the pressure of the anode in the hydrogen purification module instantly increases, and using the pressure control unit to restore the remaining gas flowing out from the anode gas outflow path to an original flow rate so that the pressure of the anode in the hydrogen purification module decreases to the original pressure.

3. The control method of the hydrogen purification system according to claim 1, wherein after the step of providing power to the hydrogen purification module, the control method further comprises performing at least one of the following cycles: measuring current and / or voltage in a plurality of membrane electrode assemblies in the hydrogen purification module; and Determine whether at least one of the following conditions occurs: (1) The total current of the plurality of membrane electrode assemblies is lower than a preset current value; (2) the voltage of at least one membrane electrode assembly is higher than a preset voltage value, When at least one of situation (1) and situation (2) occurs, the pressure control unit is used to instantly increase and decrease the pressure of the anode in the hydrogen purification module. 4 . The control method of the hydrogen purification system according to claim 3 , wherein the preset current value is 70-95% of the maximum total reaction current of the plurality of membrane electrode assemblies, and the preset voltage value is 0.15-0.30V.

5. The control method of the hydrogen purification system according to claim 3, wherein when the situation (1) and the situation (2) do not occur, the pressure of the anode in the hydrogen purification module is instantaneously increased and decreased by the pressure control unit at intervals. 6 . The control method of the hydrogen purification system according to claim 5 , wherein the period is 10 to 60 minutes. 7 . The control method of the hydrogen purification system according to claim 1 , wherein the hydrogen purification system further comprises a power supply unit, and the power supply unit is used to provide power to the hydrogen purification module.

8. The control method of the hydrogen purification system according to claim 3, wherein the hydrogen purification system further comprises an electrical property measurement unit, the electrical property measurement unit comprising a current measurement unit and a voltage measurement unit, wherein the total current of the plurality of membrane electrode assemblies is measured by the current measurement unit, and the voltage of the at least one membrane electrode assembly is measured by the voltage measurement unit.

9. The control method of the hydrogen purification system according to claim 3, wherein the control unit determines whether the total current of the plurality of membrane electrode assemblies is lower than the preset current value and / or whether the voltage in the at least one membrane electrode assembly is higher than the preset voltage value. 10 . The control method of the hydrogen purification system according to claim 9 , wherein the control unit comprises a programmable logic controller (PLC).

11. The control method of the hydrogen purification system according to claim 2, wherein the pressure control unit comprises a pressure control element and a pressure sensing element, the pressure control element reduces and / or increases the flow rate of the residual gas flowing out through the anode gas outflow path according to a signal from the control unit, and the pressure sensing element provides pressure information sensed from the anode in the hydrogen purification module to the control unit to monitor the pressure of the anode in the hydrogen purification module. 12 . The control method of the hydrogen purification system according to claim 1 , wherein the mixed gas further comprises nitrogen, carbon dioxide, carbon monoxide or a combination thereof. 13 . The control method of the hydrogen purification system according to claim 1 , wherein the mixed gas further comprises nitrogen, and the volume ratio of the hydrogen to the nitrogen is 90:10 to 50:

50.

14. A hydrogen purification system, characterized in that: include: A hydrogen purification module, comprising a plurality of membrane electrode assemblies, one of the plurality of membrane electrode assemblies comprising an anode, a cathode and a proton exchange membrane; a pressure control unit connected to the anode gas outflow path of the hydrogen purification module and capable of causing the pressure of the anode in the hydrogen purification module to rise and fall instantaneously, wherein when the pressure of the anode in the hydrogen purification module rises instantaneously, the instantaneous rise in the pressure of the anode is greater than or equal to 0.04 bar; as well as A control unit is coupled to the pressure control unit, wherein the control unit can be used to control the operation of the pressure control unit. 15 . The hydrogen purification system according to claim 14 , further comprising a power supply unit, and the power supply unit is used to provide power to the hydrogen purification module.

16. The hydrogen purification system according to claim 14, further comprising an electrical property measurement unit, the electrical property measurement unit comprising a current measurement unit and a voltage measurement unit, wherein the current measurement unit can be used to measure a total current of the plurality of membrane electrode assemblies, and the voltage measurement unit can be used to measure a voltage of the at least one membrane electrode assembly.

17. The hydrogen purification system according to claim 14, wherein the control unit comprises a programmable logic controller (PLC).

18. The hydrogen purification system according to claim 14, wherein the pressure control unit comprises a pressure control element and a pressure sensing element, the pressure control element can reduce and / or increase the flow rate of the residual gas flowing out through the anode gas outflow path according to a signal from the control unit, and the pressure sensing element can sense the pressure information of the anode. 19 . The hydrogen purification system according to claim 14 , further comprising an anode gas inflow path, the anode being coupled to the anode gas inflow path to receive the mixed gas from the anode gas inflow path. 20 . The hydrogen purification system according to claim 19 , wherein the mixed gas further comprises nitrogen, carbon dioxide, carbon monoxide or a combination thereof.

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