A hydrogen purification system and method and a water electrolysis hydrogen production system

Abstract

The present disclosure relates to a hydrogen purification system and method and a water electrolysis hydrogen production system. The hydrogen purification system includes three dryers, and the three dryers share a regeneration circulation module, which significantly reduces the number of heaters and coolers. Therefore, the manufacturing cost of the system is low. At the same time, a first gas-to-gas heat exchanger is provided in the regeneration circulation system, so that the low-temperature regenerated hydrogen before regeneration and the high-temperature regenerated tail gas after regeneration can exchange heat. On the one hand, this can make full use of the waste heat of the high-temperature regenerated tail gas, and on the other hand, it can significantly reduce the power consumption of subsequent heaters and regeneration coolers. Therefore, the energy consumption of the system is low.

Description

Technical Field

[0001] The present disclosure relates to the technical field of hydrogen purification, and in particular to a hydrogen purification system and method and a water electrolysis hydrogen production system. Background Art

[0002] Hydrogen generated by water electrolysis contains trace amounts of oxygen and a large amount of water vapor. In order to obtain high-purity hydrogen, the hydrogen generated by water electrolysis needs to be purified.

[0003] Chinese patent CN1920100A discloses a device for continuously purifying water and electrolyzing hydrogen, which includes three drying towers. Each drying tower is equipped with an electric heating rod for heating and creating a high-temperature environment when regenerating the desiccant in the drying tower; each drying tower is connected to a regeneration cooler outside to cool the high-temperature regeneration exhaust gas generated during the regeneration of the desiccant.

[0004] The above device has a large number of electric heating rods and coolers, and does not fully utilize the waste heat of the high-temperature regenerated tail gas, so there are problems of high manufacturing cost and energy waste. Summary of the invention

[0005] The purpose of the present invention is to solve the problems of high manufacturing cost and energy waste in existing hydrogen purification devices, and to provide a hydrogen purification system and method and a water electrolysis hydrogen production system.

[0006] In order to achieve the above object, the present disclosure provides a hydrogen purification system for purifying hydrogen to be purified to form purified hydrogen, the hydrogen purification system comprising:

[0007] A deoxidation module, a drying module and a regeneration circulation module connected in sequence, wherein the drying module comprises a first dryer, a second dryer and a third dryer connected in parallel; the regeneration circulation module comprises a heater and a first gas-to-gas heat exchanger having a first gas channel and a second gas channel;

[0008] The hydrogen purification system also includes:

[0009] a first gas limiting module, used for allowing the hydrogen to be purified to flow through the deoxygenation module and the first dryer in sequence to form a purification channel to obtain the purified hydrogen;

[0010] The second gas limiting module is used to supply part of the purified hydrogen to flow sequentially through the first gas channel of the first gas-to-gas heat exchanger, the heater, the second dryer, the second gas channel of the first gas-to-gas heat exchanger and the third dryer to form a regeneration channel to obtain recovered hydrogen.

[0011] Optionally, the first dryer, the second dryer and the third dryer each have a first opening and a second opening, wherein the first opening of the first dryer, the first opening of the second dryer and the first opening of the third dryer can be respectively communicated with the outlet of the deoxygenation module, the second gas channel inlet of the first gas-to-gas heat exchanger and the second gas channel outlet of the first gas-to-gas heat exchanger; the second opening of the first dryer, the second opening of the second dryer and the second opening of the third dryer can be respectively communicated with the outlet of purified hydrogen, the first gas channel inlet of the first gas-to-gas heat exchanger, the outlet of the heater and the outlet of recovered hydrogen; the first gas channel outlet of the first gas-to-gas heat exchanger is communicated with the inlet of the heater;

[0012] Wherein, the purified hydrogen outlet is used to output the purified hydrogen, and the recovered hydrogen outlet is used to output the recovered hydrogen.

[0013] Optionally, the first gas limiting module includes at least one first control valve, and the second gas limiting module includes at least one second control valve;

[0014] The first control valve is arranged between the outlet of the deoxygenation module and the first opening of each dryer and between the outlet of the purified hydrogen and the second opening of each dryer;

[0015] The second control valve is arranged between the first gas channel inlet of the first gas-to-gas heat exchanger and the second opening of each dryer, between the outlet of the heater and the second opening of each dryer, between the second gas channel inlet of the first gas-to-gas heat exchanger and the first opening of each dryer, between the second gas channel outlet of the first gas-to-gas heat exchanger and the first opening of each dryer, and between the recovered hydrogen outlet and the second opening of each dryer.

[0016] Optionally, the regeneration cycle module further includes:

[0017] A cooler, used to cool the second dryer;

[0018] The third gas limiting module is used to provide part of the purified hydrogen to flow through the cooler, the second dryer, the second gas channel of the first gas-to-gas heat exchanger and the third dryer in sequence to form a regeneration cooling channel.

[0019] Optionally, the inlet of the cooler can be connected to the second opening of the first dryer, the second opening of the second dryer and the second opening of the third dryer, respectively, and the outlet of the cooler can be connected to the second opening of the first dryer, the second opening of the second dryer and the second opening of the third dryer, respectively.

[0020] Optionally, the third air limiting module includes at least one third control valve, and the third control valve is arranged between the inlet of the cooler and the second opening of each dryer, and / or between the outlet of the cooler and the second opening of each dryer.

[0021] Optionally, the regeneration circulation module also includes a regeneration cooler and a first steam-water separator, the inlet of the regeneration cooler is connected to the second gas channel outlet of the first gas-to-gas heat exchanger, the outlet of the regeneration cooler is connected to the inlet of the first steam-water separator, and the outlet of the first steam-water separator can be connected to the first opening of the first dryer, the first opening of the second dryer or the first opening of the third dryer, respectively.

[0022] Optionally, the deoxygenation module includes a second gas-to-gas heat exchanger and a deoxygenator, the second gas-to-gas heat exchanger having a first gas channel and a second gas channel, wherein the first gas channel outlet of the second gas-to-gas heat exchanger is connected to the inlet of the deoxygenator, the outlet of the deoxygenator is connected to the second gas channel inlet of the second gas-to-gas heat exchanger, and the second gas channel outlet of the second gas-to-gas heat exchanger can be connected to the first opening of the first dryer, the first opening of the second dryer or the first opening of the third dryer, respectively.

[0023] Optionally, the hydrogen purification system further includes a cooling condenser and a second gas-water separator, wherein the inlet of the cooling condenser is communicated with the second gas channel outlet of the second gas-to-gas heat exchanger, the outlet of the cooling condenser is communicated with the inlet of the second gas-water separator, and the outlet of the second gas-water separator can be communicated with the first opening of the first dryer, the first opening of the second dryer, or the first opening of the third dryer, respectively.

[0024] Optionally, a first condensed water discharge pipe is further provided between the second gas channel inlet of the first gas-to-gas heat exchanger and the first opening of each dryer, and one end of the first condensed water discharge pipe is simultaneously connected to the second gas channel inlet of the first gas-to-gas heat exchanger and the first opening of each dryer;

[0025] A second condensate discharge pipe is further provided between the second gas channel inlet of the second gas-to-gas heat exchanger and the outlet of the deoxidizer, and the second condensate discharge pipe is simultaneously connected to the second gas channel inlet of the second gas-to-gas heat exchanger and the outlet of the deoxidizer;

[0026] The first condensate discharge pipeline and the second condensate discharge pipeline are both provided with control valves.

[0027] Optionally, a first temperature measuring device is provided on the deoxidizer, a second temperature measuring device is provided at the outlet of the deoxidizer, a third temperature measuring device is provided at the first opening of the first dryer, a fourth temperature measuring device is provided at the first opening of the second dryer, a fifth temperature measuring device is provided at the first opening of the third dryer, a sixth temperature measuring device is provided on the heater, and a seventh temperature measuring device is provided at the outlet of the heater.

[0028] Optionally, the first dryer, the second dryer and the third dryer are all cylindrical structures, and a molecular sieve desiccant is arranged in the cylinder.

[0029] The present disclosure also provides a water electrolysis hydrogen production system, which includes a water electrolysis hydrogen production module and any one of the above-mentioned hydrogen purification systems, and the water electrolysis hydrogen production module is connected to the deoxygenation module of the hydrogen purification system.

[0030] The present disclosure also provides a method for purifying hydrogen using any one of the hydrogen purification systems described above, the method for purifying hydrogen comprising:

[0031] S01. The hydrogen to be purified enters the deoxygenation module for deoxygenation to obtain deoxygenated hydrogen;

[0032] S02. The deoxygenated hydrogen enters the first dryer for drying to obtain the purified hydrogen;

[0033] S03. Separating a portion of the purified hydrogen as low-temperature regenerated hydrogen into the first gas channel of the first gas-to-gas heat exchanger for heat exchange treatment, and then entering the heater for heating treatment to obtain high-temperature regenerated hydrogen;

[0034] S04. Stop feeding the deoxygenated hydrogen into the second dryer, and allow the high-temperature regenerated hydrogen to enter the second dryer, dry and regenerate the molecular sieve desiccant in the second dryer to obtain a high-temperature regenerated tail gas;

[0035] S05. The high-temperature regeneration tail gas enters the second gas channel of the first gas-to-gas heat exchanger, and performs heat exchange with the low-temperature regeneration hydrogen in the first gas channel to obtain a low-temperature regeneration tail gas;

[0036] S06. The low-temperature regeneration tail gas enters the third dryer for drying to obtain recovered hydrogen;

[0037] S07. Combining the recovered hydrogen with the purified hydrogen.

[0038] Optionally, in operation S04, the high-temperature regenerated hydrogen and the deoxygenated hydrogen are passed into the second dryer in opposite directions.

[0039] Optionally, the method for purifying hydrogen further comprises: repeating operations S02 to S07, drying the deoxygenated hydrogen in the second dryer, drying and regenerating the molecular sieve desiccant to be regenerated in the third dryer, and drying the low-temperature regenerated tail gas in the first dryer; and / or,

[0040] Repeat operations S02 to S07, dry the deoxygenated hydrogen in the third dryer, blow dry and regenerate the molecular sieve desiccant to be regenerated in the first dryer, and dry the low-temperature regenerated tail gas in the second dryer.

[0041] Optionally, after the molecular sieve desiccant in the second dryer is dried and regenerated for a preset time using the high-temperature regenerated hydrogen in operation S04, the method for purifying hydrogen further includes:

[0042] S04-1. Stopping the low-temperature regenerated hydrogen in operation S03 from entering the first gas channel of the first gas-to-gas heat exchanger, and allowing a portion of the purified hydrogen to enter the cooler for cooling to obtain blown cold hydrogen;

[0043] S04-2. Stop allowing the high-temperature regenerated hydrogen in operation S04 to enter the second dryer, and allow the blown-cooled hydrogen to enter the second dryer, blow-cool the regenerated molecular sieve desiccant in the second dryer, and the generated gas replaces the high-temperature regenerated tail gas in operation S05, and continue to perform operations S05 to S07, wherein the gas flow direction of the blown-cooled hydrogen is the same as the gas flow direction of the high-temperature regenerated hydrogen in the second dryer.

[0044] Optionally, in operation S01, the hydrogen to be purified is allowed to enter the deoxygenation module for deoxygenation treatment to obtain deoxygenated hydrogen, including:

[0045] The hydrogen to be purified is sequentially caused to enter the first gas channel of the second gas-to-gas heat exchanger for heat exchange treatment, enter the deoxidizer for deoxygenation treatment, and enter the second gas channel of the second gas-to-gas heat exchanger for heat exchange treatment with the hydrogen to be purified in the first gas channel to obtain the deoxygenated hydrogen.

[0046] Optionally, in operation S03, the volume of the portion separated from the purified hydrogen accounts for 10-15% of the total volume of the purified hydrogen.

[0047] Optionally, in operation S01, the temperature of the deoxidation treatment is 85-100°C; in operation S02, the temperature of the drying treatment is room temperature; in operation S03, the temperature of the heating treatment is 300-350°C; in operation S04, the temperature of the blow-drying regeneration is 250-300°C; in operation S06, the temperature of the drying treatment is room temperature.

[0048] Optionally, in operation S02, before the deoxygenated hydrogen enters the first dryer, the method for purifying hydrogen further includes:

[0049] The deoxygenated hydrogen is sequentially introduced into the cooling condenser for condensation treatment and into the second steam-water separator for steam-water separation treatment.

[0050] Optionally, in operation S06, before the low-temperature regeneration tail gas enters the third dryer for drying, the method for purifying hydrogen further includes:

[0051] The low-temperature regeneration tail gas is sequentially entered into the regeneration cooler for condensation treatment and into the first steam-water separator for steam-water separation treatment.

[0052] Through the above technical scheme, the three dryers in the hydrogen purification system of the present invention share a regeneration circulation module, which significantly reduces the number of heaters and coolers. Therefore, the manufacturing cost of the system is low; at the same time, a first gas-to-gas heat exchanger is provided in the regeneration circulation system, so that the low-temperature regenerated hydrogen before regeneration and the high-temperature regenerated exhaust gas after regeneration can exchange heat. On the one hand, this can make full use of the waste heat of the high-temperature regenerated exhaust gas, and on the other hand, it can significantly reduce the power consumption of subsequent heaters and regeneration coolers. Therefore, the energy consumption of the system is low.

[0053] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings:

[0055] Figure 1 It is a schematic structural diagram of the hydrogen purification system disclosed in the present invention.

[0056] Description of Reference Numerals

[0057] 1 First dryer 2 Second dryer

[0058] 3 The third dryer 4 The first gas-to-gas heat exchanger

[0059] 5 Heater 6 Regeneration cooler

[0060] 7 First steam-water separator 8 Cooler

[0061] 9 The third steam-water separator 10 The second gas-gas heat exchanger

[0062] 11 Deaerator 12 Cooling condenser

[0063] 13 Second steam-water separator 14 First condensate discharge pipe

[0064] 15 Second condensate discharge pipe 16 First temperature measuring device

[0065] 17 Second temperature measuring device 18 Third temperature measuring device

[0066] 19 Fourth temperature measuring device 20 Fifth temperature measuring device

[0067] 21 Sixth temperature measuring device 22 Seventh temperature measuring device DETAILED DESCRIPTION

[0068] The specific implementation of the present disclosure is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the present disclosure, and is not used to limit the present disclosure.

[0069] A first aspect of the present disclosure provides a hydrogen purification system for purifying hydrogen to be purified to form purified hydrogen, such as Figure 1 As shown, the hydrogen purification system may include: a deoxygenation module, a drying module and a regeneration circulation module connected in sequence, the drying module includes a first dryer 1, a second dryer 2 and a third dryer 3 connected in parallel; the regeneration circulation module includes a heater 5 and a first gas-to-gas heat exchanger 4 having a first gas channel and a second gas channel;

[0070] The hydrogen purification system also includes: a first gas limiting module, used to supply the hydrogen to be purified to flow through the deoxygenation module and the first dryer 1 in sequence to form a purification channel to obtain the purified hydrogen; a second gas limiting module, used to supply part of the purified hydrogen to flow through the first gas channel of the first gas-to-gas heat exchanger 4, the heater 5, the second dryer 2, the second gas channel of the first gas-to-gas heat exchanger 4 and the third dryer 3 in sequence to form a regeneration channel to obtain recovered hydrogen.

[0071] According to the present disclosure, the first dryer 1, the second dryer 2 and the third dryer 3 all have a first opening and a second opening, wherein the first opening of the first dryer 1, the first opening of the second dryer 2 and the first opening of the third dryer 3 can be respectively connected to the outlet of the deoxygenation module, the second gas channel inlet of the first gas-to-gas heat exchanger 4 and the second gas channel outlet of the first gas-to-gas heat exchanger 4; the second opening of the first dryer 1, the second opening of the second dryer 2 and the second opening of the third dryer 3 can be respectively connected to the purified hydrogen outlet, the first gas channel inlet of the first gas-to-gas heat exchanger 4, the outlet of the heater 5 and the recovered hydrogen outlet; the first gas channel outlet of the first gas-to-gas heat exchanger is connected to the inlet of the heater; wherein the purified hydrogen outlet is used to output the purified hydrogen, and the recovered hydrogen outlet is used to output the recovered hydrogen.

[0072] In the present disclosure, specifically, each opening (including each outlet and each inlet) can be connected through a gas delivery pipeline. When multiple openings are connected to the same other opening at the same time, the multiple openings can be connected to the other openings independently, and the multiple openings can also be connected in parallel to the other openings through a gas delivery pipeline. In order to save the manufacturing cost of the system and simplify the complexity of the system, when multiple openings are connected to the same other opening at the same time, the present disclosure preferably connects the multiple openings in parallel to the other openings through a gas delivery pipeline.

[0073] For example, Figure 1 As shown, in the hydrogen purification system of the present invention, the first opening of the first dryer, the first opening of the second dryer and the first opening of the third dryer can be connected in parallel with each other, and then respectively communicated with the outlet of the deoxygenation module, the second gas channel inlet of the first gas-to-gas heat exchanger and the second gas channel outlet of the first gas-to-gas heat exchanger through different pipelines; the second opening of the first dryer, the second opening of the second dryer and the second opening of the third dryer can also be connected in parallel with each other, and then respectively communicated with the outlet of purified hydrogen, the first gas channel inlet of the first gas-to-gas heat exchanger, the outlet of the heater and the outlet of recovered hydrogen through different pipelines.

[0074] The hydrogen purification system disclosed in the present invention can be specifically used for purifying hydrogen generated by water electrolysis, wherein the deoxygenation module can be used to remove a small amount of oxygen contained in the hydrogen generated by water electrolysis, the drying module can be used to remove a large amount of water vapor contained in the hydrogen generated by water electrolysis, and the regeneration circulation module can be used to heat the cold air flow before regeneration and cool the hot air flow after regeneration during the regeneration process of the desiccant.

[0075] The hydrogen purification system disclosed in the present invention can simultaneously realize the purification treatment of the hydrogen to be purified, the regeneration treatment of the desiccant to be regenerated in the dryer, and the recovery treatment of the regenerated tail gas. Specifically, any one of the dryers can be used to purify the hydrogen to be purified, while the desiccant to be regenerated in another dryer can be regenerated, and the remaining dryers can be used to dry and recover the regenerated tail gas.

[0076] Specifically, when the hydrogen purification system of the present invention is in operation, the hydrogen to be purified can first be allowed to enter the deoxygenation module for deoxygenation treatment to obtain deoxygenated hydrogen; then the deoxygenated hydrogen can be allowed to enter the dryer from the first opening of any dryer for drying treatment to obtain purified hydrogen, and a portion of the purified hydrogen can be separated as low-temperature regenerated hydrogen to enter the first gas channel of the first gas-to-gas heat exchanger from the first gas channel inlet to perform heat exchange treatment, and then enter the heater through the first gas channel outlet of the first gas-to-gas heat exchanger and the inlet of the heater to perform heating treatment to obtain high-temperature regenerated hydrogen; then, the high-temperature regenerated hydrogen can be allowed to enter the dryer from the second opening of another dryer to blow dry and regenerate the molecular sieve desiccant to be regenerated in the dryer. , high-temperature regenerated tail gas is obtained, and the obtained high-temperature regenerated tail gas is made to flow out from the first opening of the dryer, and then flow into the second gas channel of the first gas-to-gas heat exchanger from the second gas channel inlet of the first gas-to-gas heat exchanger to exchange heat with the low-temperature regenerated hydrogen in the first gas channel of the first gas-to-gas heat exchanger, and then flow out through the second gas channel outlet of the first gas-to-gas heat exchanger to obtain low-temperature regenerated tail gas; next, the low-temperature regenerated tail gas is made to flow into the dryer from the first opening of the remaining dryer for drying treatment, and then flow out from the second opening of the dryer to obtain recovered hydrogen, and the recovered hydrogen is made to flow out from the recovered hydrogen outlet; finally, the purified hydrogen flowing out from the purified hydrogen outlet and the recovered hydrogen flowing out from the recovered hydrogen outlet are combined to obtain purified hydrogen.

[0077] The above-mentioned operation processes can be performed in each dryer in turn, so as to realize the continuous purification of the hydrogen to be purified. For example, the deoxygenated hydrogen can be dried in the first dryer, the molecular sieve desiccant to be regenerated in the second dryer can be blown dry and regenerated, and the low-temperature regenerated tail gas can be dried in the first dryer; then, the deoxygenated hydrogen can be dried in the second dryer, the molecular sieve desiccant to be regenerated in the third dryer can be blown dry and regenerated, and the low-temperature regenerated tail gas can be dried in the first dryer; finally, the deoxygenated hydrogen can be dried in the third dryer, the molecular sieve desiccant to be regenerated in the first dryer can be blown dry and regenerated, and the low-temperature regenerated tail gas can be dried in the second dryer. In this way, a closed-loop cycle process is formed, so as to realize the continuous purification of the hydrogen to be purified.

[0078] In the present disclosure, three dryers in the hydrogen purification system share a regeneration circulation module, which significantly reduces the number of heaters and coolers. Therefore, the manufacturing cost of the system is low. At the same time, a first gas-to-gas heat exchanger is provided in the regeneration circulation system, so that the low-temperature regenerated hydrogen before regeneration and the high-temperature regenerated exhaust gas after regeneration can exchange heat. On the one hand, this can make full use of the waste heat of the high-temperature regeneration exhaust gas, and on the other hand, it can significantly reduce the power consumption of subsequent heaters and regeneration coolers. Therefore, the energy consumption of the system is low.

[0079] According to the present disclosure, the first gas limiting module may include at least one first control valve, and the second gas limiting module may include at least one second control valve; the first control valve may be arranged between the outlet of the deoxygenation module and the first opening of each dryer and between the purified hydrogen outlet and the second opening of each dryer; the second control valve may be arranged between the first gas channel inlet of the first gas-to-gas heat exchanger 4 and the second opening of each dryer, between the outlet of the heater 5 and the second opening of each dryer, between the second gas channel inlet of the first gas-to-gas heat exchanger 4 and the first opening of each dryer, between the second gas channel outlet of the first gas-to-gas heat exchanger 4 and the first opening of each dryer, and between the recovered hydrogen outlet and the second opening of each dryer.

[0080] In the present disclosure, specifically, the types of the first control valve and the second control valve can be selected within a certain range, for example, they can be pneumatic ball valves. By controlling the switching of the first control valve or the second control valve, the switching of the flow paths between the openings can be achieved to prevent the airflow from entering other flow paths. For example, by opening the first control valve between the outlet of the deoxygenation module and the first opening of the first dryer, and closing the first control valve between the outlet of the deoxygenation module and the first opening of the second dryer and the first opening of the third dryer, the flow path between the deoxygenation module and the first dryer can be opened, and the flow paths between the deoxygenation module and the second dryer and the third dryer can be closed, so that the hydrogen after deoxygenation enters the first dryer, but does not enter the second dryer and the third dryer.

[0081] According to the present disclosure, the regeneration circulation module may also include: a cooler 8 for cooling the second dryer 2; a third gas limiting module for providing part of the purified hydrogen to flow through the cooler 8, the second dryer 2, the second gas channel of the first gas-to-gas heat exchanger 4 and the third dryer 3 in sequence to form a regeneration cooling channel.

[0082] Among them, the inlet of the cooler 8 can be connected with the second opening of the first dryer 1, the second opening of the second dryer 2 and the second opening of the third dryer 3 respectively, and the outlet of the cooler 8 can be connected with the second opening of the first dryer 1, the second opening of the second dryer 2 and the second opening of the third dryer 3 respectively.

[0083] In the present disclosure, specifically, the type of cooler 8 can be selected within a certain range, for example, it can be a blow-cooled cooler, which is mainly used to cool down part of the purified hydrogen from the dryer used for drying the hydrogen to be purified after the desiccant is regenerated for a period of time, and make this part of the purified hydrogen after the cooling treatment enter the dryer used for desiccant regeneration, so as to quickly cool the high-temperature regenerated desiccant after regeneration, which can shorten the duration of the regeneration process on the one hand, and make the regenerated desiccant in a low temperature state on the other hand to increase its adsorption capacity.

[0084] That is to say, the regeneration process of the desiccant to be regenerated in the system of the present invention includes at least two operations. The first operation is to use the high-temperature regenerated hydrogen heated by the first gas-to-gas heat exchanger and the heater to remove the moisture in the desiccant to be regenerated. The second operation is to use the low-temperature purified hydrogen cooled by the cooler to quickly cool the high-temperature regenerated desiccant obtained after the first operation.

[0085] According to the present disclosure, the third gas limiting module may include at least one third control valve, which may be disposed between the inlet of the cooler 8 and the second opening of each dryer, and / or between the outlet of the cooler 8 and the second opening of each dryer. By regulating the third control valve, part of the purified hydrogen from the dryer for drying the hydrogen to be purified may flow to the cooler 8, but not to the first gas channel of the first gas-to-gas heat exchanger 4.

[0086] According to the present disclosure, the regeneration circulation module may further include a regeneration cooler 6 and a first steam-water separator 7, the inlet of the regeneration cooler 6 being connected to the second gas channel outlet of the first gas-to-gas heat exchanger 4, the outlet of the regeneration cooler 6 being connected to the inlet of the first steam-water separator 7, and the outlet of the first steam-water separator 7 being able to be connected to the first opening of the first dryer 1, the first opening of the second dryer 2 or the first opening of the third dryer 3, respectively.

[0087] According to the present disclosure, the deoxygenation module may also include a second gas-to-gas heat exchanger 10 and a deoxygenator 11, the second gas-to-gas heat exchanger 10 having a first gas channel and a second gas channel, wherein the first gas channel outlet of the second gas-to-gas heat exchanger 10 is connected to the inlet of the deoxygenator 11, the outlet of the deoxygenator 11 is connected to the second gas channel inlet of the second gas-to-gas heat exchanger 10, and the second gas channel outlet of the second gas-to-gas heat exchanger 10 can be connected to the first opening of the first dryer 1, the first opening of the second dryer 2 and the first opening of the third dryer 3, respectively.

[0088] In the present disclosure, specifically, due to the provision of the second gas-to-gas heat exchanger, the hot gas flow of hydrogen after deoxygenation in the deoxygenator can flow back into the second gas channel of the second gas-to-gas heat exchanger, and perform heat exchange heating on the low-temperature hydrogen to be purified flowing through the first gas channel, thereby increasing the temperature of the hydrogen to be purified and reducing the temperature of the deoxygenated hydrogen, which can effectively reduce the power consumption of the deoxygenator and the subsequent cooling condenser.

[0089] According to the present disclosure, the hydrogen purification system may further include a cooling condenser 12 and a second steam-water separator 13, wherein the inlet of the cooling condenser 12 is communicated with the second gas channel outlet of the second gas-to-gas heat exchanger 10, the outlet of the cooling condenser 12 is communicated with the inlet of the second steam-water separator 13, and the outlet of the second steam-water separator 13 can be communicated with the first opening of the first dryer 1, the first opening of the second dryer 2, and the first opening of the third dryer 3, respectively.

[0090] According to the present disclosure, a first condensed water discharge pipe 14 may be further provided between the second gas channel inlet of the first gas-to-gas heat exchanger 4 and the first opening of each dryer, and one end of the first condensed water discharge pipe 14 is simultaneously connected to the second gas channel inlet of the first gas-to-gas heat exchanger 4 and the first opening of each dryer; a second condensed water discharge pipe 15 may also be provided between the second gas channel inlet of the second gas-to-gas heat exchanger 10 and the outlet of the deoxidizer 11, and the second condensed water discharge pipe 15 is simultaneously connected to the second gas channel inlet of the second gas-to-gas heat exchanger 10 and the outlet of the deoxidizer 11. Both the first condensed water discharge pipe and the second condensed water discharge pipe are used to discharge the condensed water accumulated in the gas flow path to prevent the condensed water from entering the gas-to-gas heat exchanger and affecting the heat exchange effect.

[0091] According to the present disclosure, both the first condensate discharge pipe 14 and the second condensate discharge pipe 15 may be provided with a control valve.

[0092] According to the present disclosure, the deoxidizer 11 may be provided with a first temperature measuring device 16, the outlet of the deoxidizer 11 may be provided with a second temperature measuring device 17, the first opening of the first dryer 1 may be provided with a third temperature measuring device 18, the first opening of the second dryer 2 may be provided with a fourth temperature measuring device 19, the first opening of the third dryer 3 may be provided with a fifth temperature measuring device 20, the heater 5 may be provided with a sixth temperature measuring device 21, and the outlet of the heater 5 may be provided with a seventh temperature measuring device 22.

[0093] According to the present disclosure, the first dryer 1, the second dryer 2 and the third dryer 3 are all cylindrical structures, and a molecular sieve desiccant is arranged in the cylinder. Since each dryer in the system of the present disclosure shares an air-to-air heat exchanger and a heater, there is no need to set an electric heating device in each dryer, and the energy-saving and emission-reduction effect is obvious.

[0094] A second aspect of the present disclosure provides a water electrolysis hydrogen production system, which may include a water electrolysis hydrogen production module and any one of the above-mentioned hydrogen purification systems, wherein the water electrolysis hydrogen production module is connected to the deoxygenation module of the hydrogen purification system.

[0095] A third aspect of the present disclosure provides a method for purifying hydrogen using any one of the systems described above, and the method may include operations S01 to S07.

[0096] In operation S01, the hydrogen to be purified is introduced into the deoxygenation module for deoxygenation to obtain deoxygenated hydrogen. The hydrogen to be purified may be, for example, hydrogen generated by water electrolysis.

[0097] In operation S02, the deoxygenated hydrogen is allowed to enter the first dryer for drying to obtain the purified hydrogen.

[0098] In operation S03, a portion of the purified hydrogen is separated as low-temperature regenerated hydrogen and enters the first gas channel of the first gas-to-gas heat exchanger for heat exchange treatment, and then enters the heater for heating treatment to obtain high-temperature regenerated hydrogen.

[0099] In operation S04, the introduction of the deoxygenated hydrogen into the second dryer is stopped, and the high-temperature regenerated hydrogen is allowed to enter the second dryer to dry and regenerate the molecular sieve desiccant to be regenerated in the second dryer to obtain high-temperature regenerated tail gas.

[0100] In operation S05, the high-temperature regeneration tail gas is allowed to enter the second gas channel of the first gas-to-gas heat exchanger, and is heat exchanged with the low-temperature regeneration hydrogen in the first gas channel to obtain low-temperature regeneration tail gas.

[0101] In operation S06, the low-temperature regeneration tail gas is allowed to enter the third dryer for drying to obtain recovered hydrogen.

[0102] In operation S07, the recovered hydrogen is combined with the purified hydrogen.

[0103] According to the present disclosure, in operation S04, the high-temperature regenerated hydrogen and the deoxygenated hydrogen flow into the second dryer in opposite directions.

[0104] According to the present disclosure, the method for purifying hydrogen may further include: repeating operations S02 to S07, drying the deoxygenated hydrogen in the second dryer, blowing dry and regenerating the molecular sieve desiccant to be regenerated in the third dryer, and drying the low-temperature regenerated tail gas in the first dryer; and / or repeating operations S02 to S07, drying the deoxygenated hydrogen in the third dryer, blowing dry and regenerating the molecular sieve desiccant to be regenerated in the first dryer, and drying the low-temperature regenerated tail gas in the second dryer.

[0105] According to the present disclosure, after the molecular sieve desiccant in the second dryer is blown dry and regenerated for a preset time using the high-temperature regenerated hydrogen in operation S04, the hydrogen purification method may further include operations S04-1 and S04-2.

[0106] In operation S04-1, the low-temperature regenerated hydrogen in operation S03 is stopped from entering the first gas channel of the first gas-to-gas heat exchanger, and a portion of the purified hydrogen is allowed to enter the cooler for cooling treatment to obtain blown cold hydrogen.

[0107] In operation S04-2, the high-temperature regenerated hydrogen in operation S04 is stopped from entering the second dryer, and the blown-cooled hydrogen is allowed to enter the second dryer, the regenerated molecular sieve desiccant in the second dryer is blown-cooled, and the generated gas replaces the high-temperature regenerated tail gas in operation S05, and operations S05 to S07 are continued, wherein the gas flow direction of the blown-cooled hydrogen is the same as the gas flow direction of the high-temperature regenerated hydrogen in the second dryer.

[0108] According to the present disclosure, in operation S01, allowing the hydrogen to be purified to enter the deoxygenation module for deoxygenation treatment to obtain deoxygenated hydrogen may include: allowing the hydrogen to be purified to sequentially enter the first gas channel of the second gas-to-gas heat exchanger for heat exchange treatment, enter the deoxygenator for deoxygenation treatment, enter the second gas channel of the second gas-to-gas heat exchanger for heat exchange treatment with the hydrogen to be purified in the first gas channel to obtain the deoxygenated hydrogen.

[0109] According to the present disclosure, in operation S03, the volume of the portion separated from the purified hydrogen may account for 10-15% of the total volume of the purified hydrogen.

[0110] According to the present disclosure, in operation S01, the temperature of the deoxidation treatment can be 85-100°C; in operation S02, the temperature of the drying treatment can be room temperature; in operation S03, the temperature of the heating treatment can be 300-350°C; in operation S04, the temperature of the blow-drying regeneration can be 250-300°C; in operation S06, the temperature of the drying treatment can be room temperature.

[0111] According to the present disclosure, in operation S02, before allowing the deoxygenated hydrogen to enter the first dryer, the method for purifying hydrogen further includes: allowing the deoxygenated hydrogen to sequentially enter the cooling condenser for condensation treatment and enter the second steam-water separator for steam-water separation treatment.

[0112] According to the present disclosure, in operation S06, before allowing the low-temperature regeneration tail gas to enter the third dryer for drying treatment, the method for purifying hydrogen also includes: allowing the low-temperature regeneration tail gas to enter the regeneration cooler in sequence for condensation treatment and enter the first steam-water separator for steam-water separation treatment.

[0113] It should be noted that in the embodiments of the present disclosure, the implementation of the method part is the same as or similar to the implementation of the system part, and will not be repeated here.

[0114] The present disclosure is further described below by way of examples, but the present disclosure is not limited thereby. The raw materials, reagents, instruments and equipment involved in the examples of the present disclosure can all be purchased unless otherwise specified.

[0115] Example 1

[0116] based on Figure 1 The system shown uses the following method to purify hydrogen from water electrolysis:

[0117] (1) allowing the hydrogen to be purified to enter the first gas channel of the second gas-to-gas heat exchanger for heat exchange treatment, then enter the deoxidizer for deoxygenation treatment, and finally enter the second gas channel of the second gas-to-gas heat exchanger for heat exchange treatment with the hydrogen to be purified in the first gas channel to obtain deoxygenated hydrogen;

[0118] (2) allowing the deoxygenated hydrogen to enter a cooling condenser for condensation treatment, then enter a second steam-water separator for steam-water separation treatment, and then enter the first dryer from a first opening of the first dryer for drying treatment to obtain purified hydrogen;

[0119] (3) Separating 15% of the purified hydrogen as low-temperature regenerated hydrogen and entering the first gas channel of the first gas-to-gas heat exchanger for heat exchange treatment, and then entering the heater for heating treatment to obtain high-temperature regenerated hydrogen;

[0120] (4) stopping the introduction of deoxygenated hydrogen into the first opening of the second dryer, and allowing the high-temperature regenerated hydrogen to enter the second dryer from the second opening of the second dryer, drying and regenerating the molecular sieve desiccant to be regenerated in the second dryer, and obtaining high-temperature regenerated tail gas;

[0121] (5) After the drying and regeneration in step (4) is completed, the low-temperature regenerated hydrogen in step (3) is stopped from entering the first gas channel of the first gas-to-gas heat exchanger, and a portion of the purified hydrogen is allowed to enter the cooler for cooling treatment to obtain blown-cooled hydrogen; the high-temperature regenerated hydrogen in step (4) is stopped from entering the second dryer, and the blown-cooled hydrogen is allowed to enter the second dryer, and the regenerated molecular sieve desiccant in the second dryer is blown-cooled to obtain blown-cooled hydrogen, and the process proceeds to step (6);

[0122] (6) allowing the high-temperature regenerated tail gas obtained in step (4) or the cooled hydrogen obtained in step (5) to enter the second gas channel of the first gas-to-gas heat exchanger to perform heat exchange with the low-temperature regenerated hydrogen in the first gas channel of the first gas-to-gas heat exchanger, and then sequentially passing through the regeneration cooler and the first steam-water separator to obtain low-temperature regenerated tail gas;

[0123] (7) allowing the low-temperature regeneration tail gas to enter the third dryer for drying to obtain recovered hydrogen;

[0124] (8) After the operations of steps (2) to (7) have continued for 24 hours, the operations related to the dryer in steps (2) and (3) are transferred to the second dryer, the operations related to the dryer in steps (4) to (6) are transferred to the third dryer, and the operations related to the dryer in step (7) are transferred to the first dryer;

[0125] (9) After 24 hours, the operations related to the dryer in steps (2) and (3) are transferred to the third dryer, the operations related to the dryer in steps (4) to (6) are transferred to the first dryer, and the operations related to the dryer in step (7) are transferred to the second dryer;

[0126] (10) All the purified hydrogen and all the recovered hydrogen are combined to obtain a hydrogen product, and the operations of steps (1) to (9) are repeated to achieve continuous purification of water electrolysis hydrogen.

[0127] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings; however, the present disclosure is not limited to the specific details in the above embodiments. Within the technical concept of the present disclosure, a variety of simple modifications can be made to the technical solution of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0128] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0129] In addition, various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A hydrogen purification system for purifying hydrogen to be purified to form purified hydrogen, characterized in that: The hydrogen purification system comprises: A deoxidation module, a drying module and a regeneration circulation module connected in sequence, wherein the drying module comprises a first dryer, a second dryer and a third dryer connected in parallel; the regeneration circulation module comprises a heater and a first gas-to-gas heat exchanger having a first gas channel and a second gas channel; The hydrogen purification system also includes: a first gas limiting module, used for allowing the hydrogen to be purified to flow through the deoxygenation module and the first dryer in sequence to form a purification channel to obtain the purified hydrogen; a second gas limiting module, configured to provide part of the purified hydrogen to flow sequentially through the first gas channel of the first gas-to-gas heat exchanger, the heater, the second dryer, the second gas channel of the first gas-to-gas heat exchanger and the third dryer to form a regeneration channel to obtain recycled hydrogen; The first dryer, the second dryer and the third dryer share one regeneration cycle module.

2. The hydrogen purification system according to claim 1, characterized in that: The first dryer, the second dryer and the third dryer each have a first opening and a second opening, wherein the first opening of the first dryer, the first opening of the second dryer and the first opening of the third dryer can be respectively communicated with the outlet of the deoxygenation module, the second gas channel inlet of the first gas-to-gas heat exchanger and the second gas channel outlet of the first gas-to-gas heat exchanger; the second opening of the first dryer, the second opening of the second dryer and the second opening of the third dryer can be respectively communicated with the outlet of purified hydrogen, the first gas channel inlet of the first gas-to-gas heat exchanger, the outlet of the heater and the outlet of recovered hydrogen; the first gas channel outlet of the first gas-to-gas heat exchanger is communicated with the inlet of the heater; Wherein, the purified hydrogen outlet is used to output the purified hydrogen, and the recovered hydrogen outlet is used to output the recovered hydrogen.

3. The hydrogen purification system according to claim 2, characterized in that: The first gas limiting module includes at least one first control valve, and the second gas limiting module includes at least one second control valve; The first control valve is arranged between the outlet of the deoxygenation module and the first opening of each dryer and between the outlet of the purified hydrogen and the second opening of each dryer; The second control valve is arranged between the first gas channel inlet of the first gas-to-gas heat exchanger and the second opening of each dryer, between the outlet of the heater and the second opening of each dryer, between the second gas channel inlet of the first gas-to-gas heat exchanger and the first opening of each dryer, between the second gas channel outlet of the first gas-to-gas heat exchanger and the first opening of each dryer, and between the recovered hydrogen outlet and the second opening of each dryer.

4. The hydrogen purification system according to claim 1, characterized in that: The regeneration cycle module also includes: A cooler, used to cool the second dryer; The third gas limiting module is used to provide part of the purified hydrogen to flow through the cooler, the second dryer, the second gas channel of the first gas-to-gas heat exchanger and the third dryer in sequence to form a regeneration cooling channel.

5. The hydrogen purification system according to claim 4, characterized in that: The inlet of the cooler can be communicated with the second opening of the first dryer, the second opening of the second dryer and the second opening of the third dryer, respectively, and the outlet of the cooler can be communicated with the second opening of the first dryer, the second opening of the second dryer and the second opening of the third dryer, respectively.

6. The hydrogen purification system according to claim 5, characterized in that: The third air limiting module includes at least one third control valve, and the third control valve is arranged between the inlet of the cooler and the second opening of each dryer, and / or between the outlet of the cooler and the second opening of each dryer.

7. The hydrogen purification system according to claim 1, characterized in that: The regeneration circulation module also includes a regeneration cooler and a first steam-water separator, the inlet of the regeneration cooler is connected to the second gas channel outlet of the first gas-to-gas heat exchanger, the outlet of the regeneration cooler is connected to the inlet of the first steam-water separator, and the outlet of the first steam-water separator can be connected to the first opening of the first dryer, the first opening of the second dryer or the first opening of the third dryer respectively.

8. The hydrogen purification system according to claim 1, characterized in that: The deoxygenation module includes a second gas-to-gas heat exchanger and a deoxygenator, the second gas-to-gas heat exchanger having a first gas channel and a second gas channel, wherein the first gas channel outlet of the second gas-to-gas heat exchanger is connected to the inlet of the deoxygenator, the outlet of the deoxygenator is connected to the second gas channel inlet of the second gas-to-gas heat exchanger, and the second gas channel outlet of the second gas-to-gas heat exchanger can be connected to the first opening of the first dryer, the first opening of the second dryer or the first opening of the third dryer, respectively.

9. The hydrogen purification system according to claim 8, characterized in that: The hydrogen purification system further includes a cooling condenser and a second gas-water separator, wherein the inlet of the cooling condenser is communicated with the outlet of the second gas channel of the second gas-to-gas heat exchanger, the outlet of the cooling condenser is communicated with the inlet of the second gas-water separator, and the outlet of the second gas-water separator can be communicated with the first opening of the first dryer, the first opening of the second dryer, or the first opening of the third dryer, respectively.

10. The hydrogen purification system according to claim 8, characterized in that: A first condensed water discharge pipe is further provided between the second gas channel inlet of the first gas-to-gas heat exchanger and the first opening of each dryer, and one end of the first condensed water discharge pipe is simultaneously connected to the second gas channel inlet of the first gas-to-gas heat exchanger and the first opening of each dryer; A second condensate discharge pipe is further provided between the second gas channel inlet of the second gas-to-gas heat exchanger and the outlet of the deoxidizer, and the second condensate discharge pipe is simultaneously connected to the second gas channel inlet of the second gas-to-gas heat exchanger and the outlet of the deoxidizer; The first condensate discharge pipeline and the second condensate discharge pipeline are both provided with control valves.

11. The hydrogen purification system according to claim 8, characterized in that: The deoxidizer is provided with a first temperature measuring device, a second temperature measuring device is provided at the outlet of the deoxidizer, a third temperature measuring device is provided at the first opening of the first dryer, a fourth temperature measuring device is provided at the first opening of the second dryer, a fifth temperature measuring device is provided at the first opening of the third dryer, a sixth temperature measuring device is provided on the heater, and a seventh temperature measuring device is provided at the outlet of the heater.

12. The hydrogen purification system according to any one of claims 1 to 11, characterized in that: The first dryer, the second dryer and the third dryer are all cylindrical structures, and molecular sieve desiccant is arranged in the cylinder.

13. A system for producing hydrogen by electrolysis of water, characterized in that: The water electrolysis hydrogen production system comprises a water electrolysis hydrogen production module and the hydrogen purification system according to any one of claims 1 to 12, and the water electrolysis hydrogen production module is connected to the deoxygenation module of the hydrogen purification system.

14. A method for purifying hydrogen using the hydrogen purification system according to any one of claims 1 to 12, characterized in that: The method for purifying hydrogen comprises: S01. allowing the hydrogen to be purified to enter the deoxygenation module for deoxygenation treatment to obtain deoxygenated hydrogen; S02. allowing the deoxygenated hydrogen to enter the first dryer for drying to obtain the purified hydrogen; S03. Separating a portion of the purified hydrogen as low-temperature regenerated hydrogen and entering the first gas channel of the first gas-to-gas heat exchanger for heat exchange treatment, and then entering the heater for heating treatment to obtain high-temperature regenerated hydrogen; S04. Stop feeding the deoxygenated hydrogen into the second dryer, and allow the high-temperature regenerated hydrogen to enter the second dryer, dry and regenerate the molecular sieve desiccant in the second dryer, and obtain high-temperature regenerated tail gas; S05. allowing the high-temperature regeneration tail gas to enter the second gas channel of the first gas-to-gas heat exchanger, and to perform heat exchange treatment with the low-temperature regeneration hydrogen in the first gas channel to obtain low-temperature regeneration tail gas; S06. allowing the low-temperature regeneration tail gas to enter the third dryer for drying to obtain recovered hydrogen; S07. Combining the recovered hydrogen with the purified hydrogen.

15. The method for purifying hydrogen according to claim 14, characterized in that: In operation S04, the high-temperature regenerated hydrogen and the deoxygenated hydrogen are passed into the second dryer in opposite directions.

16. The method for purifying hydrogen according to claim 14, characterized in that: The method for purifying hydrogen further comprises: repeating operations S02 to S07, drying the deoxygenated hydrogen in the second dryer, drying and regenerating the molecular sieve desiccant to be regenerated in the third dryer, and drying the low-temperature regenerated tail gas in the first dryer; and / or, Repeat operations S02 to S07, dry the deoxygenated hydrogen in the third dryer, blow dry and regenerate the molecular sieve desiccant to be regenerated in the first dryer, and dry the low-temperature regenerated tail gas in the second dryer.

17. The method for purifying hydrogen according to claim 14, characterized in that: After the molecular sieve desiccant in the second dryer is dried and regenerated for a preset time using the high-temperature regenerated hydrogen in operation S04, the method for purifying hydrogen further includes: S04-1. Stop allowing the low-temperature regenerated hydrogen in operation S03 to enter the first gas channel of the first gas-to-gas heat exchanger, and allow a portion of the purified hydrogen to enter the cooler for cooling treatment to obtain blown cold hydrogen; S04-2. Stop allowing the high-temperature regenerated hydrogen in operation S04 to enter the second dryer, and allow the cooling hydrogen to enter the second dryer, perform cooling treatment on the regenerated molecular sieve desiccant in the second dryer, and the generated gas replaces the high-temperature regenerated tail gas in operation S05, and continue to perform operations S05 to S07, wherein the gas flow direction of the cooling hydrogen is the same as the gas flow direction of the high-temperature regenerated hydrogen in the second dryer.

18. The method for purifying hydrogen according to claim 14, characterized in that: In operation S01, the hydrogen to be purified enters the deoxygenation module for deoxygenation treatment to obtain deoxygenated hydrogen, including: The hydrogen to be purified is sequentially caused to enter the first gas channel of the second gas-to-gas heat exchanger for heat exchange treatment, enter the deoxidizer for deoxygenation treatment, and enter the second gas channel of the second gas-to-gas heat exchanger for heat exchange treatment with the hydrogen to be purified in the first gas channel to obtain the deoxygenated hydrogen.

19. The method for purifying hydrogen according to any one of claims 14 to 18, characterized in that: In operation S03, the volume of the portion separated from the purified hydrogen accounts for 10-15% of the total volume of the purified hydrogen.

20. The method for purifying hydrogen according to any one of claims 14 to 18, characterized in that: In operation S01, the temperature of the deoxidation treatment is 85-100°C; in operation S02, the temperature of the drying treatment is room temperature; in operation S03, the temperature of the heating treatment is 300-350°C; in operation S04, the temperature of the blow-drying regeneration is 250-300°C; in operation S06, the temperature of the drying treatment is room temperature.

21. The method for purifying hydrogen according to any one of claims 14 to 18, characterized in that: In operation S02, before the deoxygenated hydrogen enters the first dryer, the method for purifying hydrogen further includes: The deoxygenated hydrogen is sequentially introduced into the cooling condenser for condensation treatment and into the second steam-water separator for steam-water separation treatment.

22. The method for purifying hydrogen according to any one of claims 14 to 18, characterized in that: In operation S06, before the low-temperature regeneration tail gas enters the third dryer for drying, the method for purifying hydrogen further includes: The low-temperature regeneration tail gas is sequentially entered into the regeneration cooler for condensation treatment and into the first steam-water separator for steam-water separation treatment.

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