A hydrogen recovery system and method for a sorption-based hydrogen purification process

Abstract

The present application relates to a kind of hydrogen recovery system and method for adsorption type hydrogen purification process, belong to large-scale turbine generator hydrogen oil water system field.Adsorption type purification process module is sealedly connected with hydrogen recovery process module to form hydrogen recovery loop;A tower and B tower in purification module are connected in parallel, two tower bottoms are connected with hydrogen import and emptying recovery pipeline, top is connected with hydrogen export, bottom is connected through pressure equalization pneumatic angle valve PV1, top is connected through valve MV;Hydrogen recovery process module is connected with the adsorption tower to be emptied, respectively to hydrogen export side and impurity gas emptying port;Compressor inlet end is connected with emptying recovery pipeline through pneumatic angle valve PV2, outlet end is connected with hydrogen export side through check valve ZV1, pneumatic angle valve PV3 is connected with PV2, compressor and ZV1 in series combination and parallel connection to form regeneration emptying bypass.The present application replaces direct emptying with compressor recovery, recovers high-purity hydrogen in tower before regeneration into generator, and greatly reduces process hydrogen consumption.

Description

Technical Field

[0001] This invention relates to a hydrogen recovery method for an adsorption-type hydrogen purification process, belonging to the technical field of hydrogen-oil-water systems for large steam turbine generators. Background Technology

[0002] The adsorption-based hydrogen purification process commonly employs Pressure Swing Adsorption (PSA) technology. This technology leverages the differences in adsorption characteristics of different gas components on an adsorbent. Under high pressure, a specialized adsorbent selectively adsorbs impurities in the mixed gas, while under low pressure, the adsorbent desorbs and regenerates, thus achieving gas purification and separation. This process can efficiently and completely separate impurities such as oxygen, nitrogen, and carbon dioxide from generator hydrogen, resulting in high purification efficiency.

[0003] In existing adsorption-based hydrogen purification processes, the adsorption tower needs to be vented before regeneration, meaning the gas inside the tower is directly discharged before the regeneration process begins. However, in the practical application scenarios of large steam turbine generator sets, this direct venting method has significant shortcomings: the adsorption tower still contains relatively high-purity hydrogen immediately after adsorption, and directly venting it results in a certain degree of hydrogen waste and increases the overall hydrogen consumption of the adsorption-based hydrogen purification process. For power plants, higher hydrogen consumption not only increases operating costs but may also fail to meet the stringent hydrogen consumption requirements of generator sets.

[0004] Therefore, it is necessary to develop a new hydrogen recovery method to recover the hydrogen from the pre-regeneration venting stage of the adsorption tower into the generator, replacing the traditional direct venting method. This would effectively reduce the hydrogen consumption of the adsorption-based hydrogen purification process and better meet the operational requirements of the hydrogen-oil-water system of a large steam turbine generator. Summary of the Invention

[0005] The purpose of this invention is to provide a hydrogen recovery system and method for adsorption-based hydrogen purification processes, replacing the original method of directly venting the adsorption tower before regeneration. This solves the technical problem in existing technologies where high-purity hydrogen is directly vented during the venting stage, resulting in hydrogen waste and high overall hydrogen consumption. The aim is to use compressor recovery technology to recover the high-purity hydrogen that would otherwise need to be vented back into the generator without increasing additional hydrogen consumption, thereby reducing the hydrogen consumption of the adsorption-based hydrogen purification process and enabling the generator set to better meet performance requirements.

[0006] To achieve the above objectives, the present invention provides a hydrogen recovery system for an adsorption-type hydrogen purification process, comprising:

[0007] The adsorption purification process module, as the main unit for hydrogen purification, has a hydrogen inlet at the bottom and a hydrogen outlet at the top. The module contains two towers, A and B, arranged in parallel, as well as corresponding pneumatic valves and pipe fittings. Towers A and B are arranged in parallel, with the bottom of both towers connected to the hydrogen inlet and the venting and recovery pipeline, and the top of both towers connected to the hydrogen outlet. The bottoms of the two towers are connected to each other by a pressure equalization pneumatic valve PV1, and the tops of the two towers are connected to each other by a valve MV. The hydrogen recovery process module, as an auxiliary unit for recovery, includes a compressor, a check valve, a pneumatic control angle valve, and corresponding piping and fittings. This module is connected to the adsorption tower to be emptied in the adsorption purification process module via pipelines, and leads to the hydrogen outlet side and the impurity gas venting port of the adsorption hydrogen purification process, respectively. The compressor serves as the power source for hydrogen recovery. Its inlet end is connected to the venting and recovery pipeline from the adsorption purification process module via a pneumatic angle valve PV2, and its outlet end leads to the hydrogen outlet side via a check valve ZV1. At the same time, the pneumatic angle valve PV3 is arranged in parallel with the series combination of the pneumatic angle valve PV2, the compressor, and the check valve ZV1 to form a regeneration venting bypass leading to the impurity gas venting port. The adsorption purification process module and the hydrogen recovery process module are connected by a sealed pipeline to form a complete hydrogen recovery loop.

[0008] Preferably, the bottom inlet of tower A is connected to the hydrogen inlet via a pneumatic angle valve PVA1, the bottom outlet of tower A is connected to the venting and recovery pipeline and the hydrogen recovery process module via a pneumatic angle valve PVA2, and the top outlet of tower A is connected to the hydrogen outlet via a pneumatic angle valve PVA3; the bottom inlet of tower B is connected to the hydrogen inlet via a pneumatic angle valve PVB1, the bottom outlet of tower B is connected to the venting and recovery pipeline and the hydrogen recovery process module via a pneumatic angle valve PVB2, and the top outlet of tower B is connected to the hydrogen outlet via a pneumatic angle valve PVB3.

[0009] Preferably, the check valve ZV1 is located between the outlet end of the compressor and the hydrogen outlet side to ensure unidirectional flow of recovered hydrogen and prevent high-pressure hydrogen on the hydrogen outlet side from flowing back into the recovery pipeline and adsorption tower after the compressor stops.

[0010] The present invention provides a hydrogen recovery method for an adsorption-type hydrogen purification process, which uses a compressor recovery method to replace the direct venting method before adsorption tower regeneration, and includes the following steps: In the pressure equalization step, when the adsorption tower is about to enter the regeneration state, the tower to be regenerated, which has just finished adsorption and is in a high-pressure state, is connected to the working tower, which has completed regeneration and is in a low-pressure state, through a pressure equalization pneumatic angle valve to balance the pressure of the two towers. In the recovery step, the pressure equalization pneumatic angle valve is closed, the working tower enters the adsorption state, the compressor and its pneumatic control angle valve are turned on, the high-purity hydrogen in the tower to be regenerated is extracted and pressurized and then recovered to the hydrogen outlet side of the adsorption hydrogen purification process until the tower to be regenerated reaches the atmospheric pressure state. In the regeneration step, shut down the compressor and its pneumatic control valve, open the regeneration pneumatic control valve, and wait for the regeneration tower to carry out the normal regeneration process. In this system, tower A and tower B alternately perform adsorption and regeneration, enabling continuous and uninterrupted operation of both towers.

[0011] Preferably, in the pressure equalization step, pneumatic angle valves PVA1, PVA2, PVA3, PVB1, PVB2, PVB3 and PV2 and PV3 in the hydrogen recovery process module are all in the closed state, the compressor is in the stopped state, and the pressure equalization pneumatic angle valve PV1 is opened, so that the bottoms of tower A and tower B are connected to each other and gas exchange occurs until the pressure of the two towers reaches equilibrium.

[0012] Preferably, in the recovery step, the equalizing pneumatic angle valve PV1 is closed, the pneumatic angle valves PVA1 and PVA3 on the working tower side are open while PVA2 remains closed, so that the working tower is in the adsorption working state; the pneumatic angle valves PVB1, PVB3 and PV3 on the regeneration tower side remain closed while the pneumatic angle valves PVB2 and PV2 are open, and the compressor is turned on at the same time. The hydrogen with higher purity in the regeneration tower is drawn in by the compressor and pressurized, and then transported to the hydrogen outlet side of the adsorption hydrogen purification process through the check valve ZV1 until the regeneration tower reaches the atmospheric pressure state.

[0013] Preferably, in the regeneration step, the pneumatic angle valves on the working tower side remain in the same state to continue adsorption and purification; when the pneumatic angle valves PVB1, PVB3 and PV2 on the waiting-to-regenerate tower side are closed, the compressor stops, while the pneumatic angle valves PVB2 and PV3 are opened, the waiting-to-regenerate tower is connected to the impurity gas vent through the pneumatic angle valves PVB2 and PV3 to carry out the conventional regeneration process, and the impurity gas desorbed from the adsorbent is discharged through the impurity gas vent.

[0014] Preferably, the pressure equalization step, the recovery step, and the regeneration step are executed sequentially under the centralized control of the PLC program, while the working tower maintains the adsorption working state, thereby realizing the alternating and continuous operation of the two towers.

[0015] Preferably, in the recovery step, the high-purity hydrogen that originally needed to be vented from the regeneration tower is recovered to the hydrogen outlet side of the adsorption hydrogen purification process, and merged with the hydrogen purified by the working tower before returning to the generator, thereby replacing the original method of directly venting the adsorption tower and reducing the hydrogen consumption of the adsorption hydrogen purification process.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects: This invention replaces the original direct venting method of the adsorption tower with a compressor recovery method. During the venting stage before adsorption tower regeneration, the high-purity hydrogen that would otherwise need to be vented is drawn in and pressurized by a compressor and recovered to the hydrogen outlet side of the adsorption-based hydrogen purification process. Ultimately, it returns to the generator for reuse, significantly reducing the hydrogen consumption of the original process. This effectively solves the problem of hydrogen waste and high overall hydrogen consumption in power plant applications, which makes it difficult to meet the hydrogen consumption requirements of generator sets. Furthermore, the hydrogen recovery process runs parallel to the adsorption purification process. The recovered hydrogen and purified hydrogen are combined and returned to the generator, without affecting the original purification efficiency of the adsorption-based hydrogen purification process or the continuous alternating operation of the two towers. The recovered hydrogen has high purity and can be directly returned to the generator for reuse, demonstrating good economic efficiency and practicality. Attached Figure Description

[0017] Figure 1 This is an exploded flow chart (step 1) of the adsorption purification process in the hydrogen recovery system and method for adsorption hydrogen purification process of the present invention. Figure 2 This is an exploded flow chart (step 2) of the adsorption purification process in the hydrogen recovery system and method for adsorption hydrogen purification process of the present invention. Figure 3 This is a flowchart of the adsorption purification process (step 3) in the hydrogen recovery system and method for adsorption hydrogen purification process of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] This invention discloses a hydrogen recovery method and a corresponding hydrogen recovery system for an adsorption-type hydrogen purification process. Applied to the adsorption-type hydrogen purification process in the hydrogen-oil-water system of a large steam turbine generator, this method replaces the original process of directly venting the adsorption tower before regeneration. It recovers the high-purity hydrogen that originally needed to be vented back into the generator, thereby significantly reducing the hydrogen consumption of the adsorption-type hydrogen purification process and enabling the generator set to better meet performance requirements for hydrogen consumption.

[0020] The hydrogen recovery system used in this embodiment of the invention mainly comprises two parts: an adsorption purification process module and a hydrogen recovery process module. These two modules are connected by a sealed pipeline, forming a complete hydrogen recovery loop. The adsorption purification process module, as the main unit for hydrogen purification, has a hydrogen inlet at the bottom and a hydrogen outlet at the top. Inside the module are two adsorption towers, A and B, arranged in parallel, along with corresponding pneumatic valves and piping. The hydrogen recovery process module, as an auxiliary unit for recovery, mainly includes a compressor, a check valve, a pneumatic control valve, and a series of piping components. This module is connected to the adsorption towers to be emptied in the adsorption purification process module via pipelines, and leads to the hydrogen outlet and impurity gas vent of the adsorption hydrogen purification process, respectively.

[0021] In the adsorption purification process module, tower A and tower B are arranged in parallel. The bottom of both towers is connected to the hydrogen inlet and the venting and recovery pipeline, and the top of both towers is connected to the hydrogen outlet. The bottoms of the two towers are connected to each other via a pressure-equalizing pneumatic angle valve PV1, and the tops of the two towers are connected to each other via valve MV. Specifically, the bottom inlet of tower A is connected to the hydrogen inlet via pneumatic angle valve PVA1, the bottom outlet of tower A is connected to the venting and recovery pipeline and the hydrogen recovery process module via pneumatic angle valve PVA2, and the top outlet of tower A is connected to the hydrogen outlet via pneumatic angle valve PVA3. Similarly, the bottom inlet of tower B is connected to the hydrogen inlet via pneumatic angle valve PVB1, the bottom outlet of tower B is connected to the venting and recovery pipeline and the hydrogen recovery process module via pneumatic angle valve PVB2, and the top outlet of tower B is connected to the hydrogen outlet via pneumatic angle valve PVB3. Pneumatic angle valves PVA1, PVA2, PVA3, PVB1, PVB2, PVB3, PV1 and valve MV together constitute the fluid control network of the adsorption purification process module. The switching of different process states such as adsorption, pressure equalization, recovery and regeneration of the two towers is realized by the combination of opening and closing of each valve.

[0022] In the hydrogen recovery process module, the compressor serves as the power source for hydrogen recovery. Its inlet end is connected to the venting and recovery pipeline from the adsorption purification process module via a pneumatic angle valve PV2. The compressor's outlet end is connected to the hydrogen outlet side of the adsorption hydrogen purification process via a check valve ZV1. Simultaneously, the pneumatic angle valve PV3, along with pneumatic angle valve PV2, the compressor, and check valve ZV1, are arranged in parallel to form a regeneration venting bypass leading to the impurity gas vent. Preferably, the device used in this hydrogen recovery method mainly includes a compressor, a check valve, a pneumatic control angle valve, and a series of valves and pipe fittings. All components work together to recover high-purity hydrogen during the adsorption tower venting stage.

[0023] In the above circuit, pneumatic angle valves PVA1 and PVB1 serve as the inlet control valves for tower A and tower B, respectively, to control the entry of the hydrogen to be purified from inside the generator into the corresponding adsorption towers; pneumatic angle valves PVA2 and PVB2 serve as the bottom exhaust control valves for tower A and tower B, respectively, opening during hydrogen recovery or regeneration venting to introduce gas from the towers into the hydrogen recovery process module; pneumatic angle valves PVA3 and PVB3 serve as the top outlet control valves for tower A and tower B, respectively, to guide the hydrogen purified by the adsorbent back to the hydrogen outlet and return it to the generator; pressure equalization pneumatic angle valve PV1 serves as the pressure equalization control valve between the two towers, opening during the pressure equalization process to balance the pressure between the two towers, creating conditions for subsequent hydrogen recovery steps; valve MV serves as the control valve for the pressure equalization between the two towers. The connecting valve between the top sections is used for the purging regeneration process and can serve as a backup regeneration method for the adsorption-type hydrogen purification process. The pneumatic angle valve PV2 serves as the compressor's inlet control valve, i.e., the recovery pneumatic control angle valve, which opens during the hydrogen recovery process to connect the adsorption tower to be emptied with the compressor. The pneumatic angle valve PV3 serves as the regeneration pneumatic control angle valve, which opens during the regular regeneration process to discharge the desorbed impurity gas in the tower through the impurity gas vent. The compressor is used to draw high-purity hydrogen from the adsorption tower and pressurize it before delivering it to the hydrogen outlet side. The check valve ZV1 is located between the compressor outlet and the hydrogen outlet side to ensure unidirectional flow of recovered hydrogen and prevent high-pressure hydrogen on the hydrogen outlet side from flowing back into the recovery pipeline and adsorption tower after the compressor stops.

[0024] The following uses the venting and recovery process of adsorption tower B as an example to illustrate the specific implementation process of this hydrogen recovery method. Under the centralized control of the PLC program, the entire recovery process includes three steps in sequence: pressure equalization, recovery, and regeneration. Simultaneously, adsorption tower A maintains its adsorption operation, thus achieving continuous alternating operation of the two towers. The core concept of this method is that when the adsorption tower is ready to enter the regeneration state, pressure equalization of the two towers first transfers and retains some of the high-pressure hydrogen. Then, a compressor is used to extract the remaining high-purity hydrogen from the tower and pressurize it, sending it back to the hydrogen outlet side of the adsorption-type hydrogen purification process, allowing it to return to the generator for continued use. Only after the adsorption tower drops to atmospheric pressure and the gas inside no longer has recovery value does it switch to the conventional regeneration process.

[0025] Reference Figure 1When entering step 1, the pressure equalization process between the two towers, adsorption tower B has just finished adsorption and is preparing to enter the regeneration state, containing high-purity, high-pressure hydrogen. Adsorption tower A, on the other hand, has completed regeneration and is at a relatively low pressure. Under the control of the PLC program, pneumatic valves PVA1, PVA2, PVA3, PVB1, PVB2, and PVB3, as well as PV2 and PV3 in the hydrogen recovery process module, are all closed, the compressor is stopped, and the pressure equalization pneumatic valve PV1 is opened, connecting the bottoms of towers A and B. Gas exchange occurs between the two towers through PV1, with gas flowing from the high-pressure side to the low-pressure side until the pressures of the two towers reach equilibrium. Through pressure equalization, a portion of the high-pressure hydrogen in adsorption tower B is pre-transferred and retained in adsorption tower A, preventing loss due to venting. Simultaneously, the pressure in tower B is initially reduced, creating suitable inlet conditions for the next step of compressor recovery and preventing excessive pressure differential from impacting the compressor and the adsorbent inside the tower.

[0026] Reference Figure 2 After pressure equalization is completed, step 2 begins, namely the adsorption process in tower A and the recovery process in tower B. Under the control of the PLC program, the pressure equalization pneumatic valve PV1 is closed, and adsorption tower A enters the adsorption state. Pneumatic valves PVA1 and PVA3 are opened while PVA2 remains closed. Hydrogen gas inside the generator enters through the hydrogen inlet and then enters adsorption tower A from bottom to top through pneumatic valve PVA1 for processing. Impurities such as oxygen, nitrogen, and carbon dioxide in the hydrogen gas are adsorbed and retained by the adsorbent. The purified hydrogen gas returns to the hydrogen outlet through pneumatic valve PVA3 and returns to the generator. Simultaneously, for the adsorption tower B to be emptied, pneumatic valves PVB1, PVB3, and PV3 remain closed, while pneumatic valves PVB2 and PV2 are opened. The compressor is simultaneously activated, and adsorption tower B is connected to the compressor via pneumatic valves PVB2 and PV2. High-purity hydrogen gas is extracted from the tower by the compressor's suction, pressurized, and then transported through check valve ZV1 to the hydrogen outlet side of the adsorption-type hydrogen purification process. There, it merges with the purified hydrogen and returns to the generator. As the recovery process continues, the pressure inside adsorption tower B gradually decreases until it reaches atmospheric pressure. The amount of remaining gas in the tower is minimal, and the recovery process ends, thus completing the recovery of hydrogen from adsorption tower B to the hydrogen outlet side of the adsorption-type hydrogen purification process. Throughout this process, check valve ZV1 ensures that hydrogen flows only from the compressor to the hydrogen outlet side, preventing high-pressure hydrogen from the outlet side from flowing back into the recovery pipeline.

[0027] Reference Figure 3After recovery, the process proceeds to step 3, namely the adsorption process in tower A and the regeneration process in tower B. Under the control of the PLC program, the equalizing pneumatic valve PV1 remains closed, and the pneumatic valves on the tower A side remain unchanged, i.e., PVA1 and PVA3 remain open, and PVA2 remains closed. The hydrogen inside the generator continues to enter the adsorption tower A for processing through the pneumatic valve PVA1. The processed hydrogen returns to the generator through the pneumatic valve PVA3, and tower A maintains normal adsorption operation. At the same time, the compressor and its pneumatic control valve PV2 are shut down. The pneumatic valves PVB1 and PVB3 on the adsorption tower B side remain closed, while the pneumatic valve PVB2 remains open, and the regeneration pneumatic control valve PV3 is opened. Adsorption tower B is connected to the impurity gas vent through the pneumatic valves PVB2 and PV3 to carry out the conventional regeneration process. The adsorbent inside the tower undergoes regeneration, and the impurity gas desorbed from the adsorbent is discharged from the impurity gas vent through the pipeline containing PV3, thereby restoring the adsorbent's adsorption capacity, completing the regeneration process of adsorption tower B, and waiting to enter the next working cycle. At this time, check valve ZV1 reliably isolates the hydrogen outlet side from the recovery pipeline, preventing high-pressure hydrogen from the hydrogen outlet side from entering the venting circuit through the pipeline where the compressor is located, thus avoiding hydrogen loss.

[0028] Through the coordinated operation of the aforementioned hydrogen recovery loop and various valves and compressors, this embodiment replaces the original direct venting method of the adsorption tower with a compressor-pressurized recovery method. During the venting stage before adsorption tower regeneration, the high-purity hydrogen that would otherwise need to be vented is recovered by the compressor to the hydrogen outlet side of the adsorption-type hydrogen purification process and returned to the generator. The conventional regeneration process only proceeds after the hydrogen is recovered to atmospheric pressure. This significantly reduces the hydrogen consumption of the original adsorption-type hydrogen purification process, effectively solving the problem of hydrogen waste and high overall hydrogen consumption in power plant applications, which makes it difficult to meet the hydrogen consumption requirements of generator sets. Simultaneously, the recovery process runs parallel to the adsorption process, without affecting the original purification efficiency and continuous operation of the adsorption-type hydrogen purification process. The recovered hydrogen has high purity and can be directly returned to the generator for utilization, demonstrating good economic efficiency and practicality.

[0029] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A hydrogen recovery system for an adsorption-type hydrogen purification process, characterized in that, include: The adsorption purification process module, as the main unit for hydrogen purification, has a hydrogen inlet at the bottom and a hydrogen outlet at the top. The module contains two towers, A and B, arranged in parallel, as well as corresponding pneumatic valves and pipe fittings. Towers A and B are arranged in parallel, with the bottom of both towers connected to the hydrogen inlet and the venting and recovery pipeline, and the top of both towers connected to the hydrogen outlet. The bottoms of the two towers are connected to each other by a pressure equalization pneumatic valve PV1, and the tops of the two towers are connected to each other by a valve MV. The hydrogen recovery process module, as an auxiliary unit for recovery, includes a compressor, a check valve, a pneumatic control angle valve, and corresponding piping and fittings. This module is connected to the adsorption tower to be emptied in the adsorption purification process module via pipelines, and leads to the hydrogen outlet side and the impurity gas venting port of the adsorption hydrogen purification process, respectively. The compressor serves as the power source for hydrogen recovery. Its inlet end is connected to the venting and recovery pipeline from the adsorption purification process module via a pneumatic angle valve PV2, and its outlet end leads to the hydrogen outlet side via a check valve ZV1. At the same time, the pneumatic angle valve PV3 is arranged in parallel with the series combination of the pneumatic angle valve PV2, the compressor, and the check valve ZV1 to form a regeneration venting bypass leading to the impurity gas venting port. The adsorption purification process module and the hydrogen recovery process module are connected by a sealed pipeline to form a complete hydrogen recovery loop.

2. The hydrogen recovery system for an adsorption-type hydrogen purification process according to claim 1, characterized in that, The bottom inlet of tower A is connected to the hydrogen inlet via pneumatic angle valve PVA1, the bottom outlet of tower A is connected to the venting and recovery pipeline and the hydrogen recovery process module via pneumatic angle valve PVA2, and the top outlet of tower A is connected to the hydrogen outlet via pneumatic angle valve PVA3. The bottom inlet of tower B is connected to the hydrogen inlet via pneumatic angle valve PVB1, the bottom outlet of tower B is connected to the venting and recovery pipeline and the hydrogen recovery process module via pneumatic angle valve PVB2, and the top outlet of tower B is connected to the hydrogen outlet via pneumatic angle valve PVB3.

3. The hydrogen recovery system for an adsorption-type hydrogen purification process according to claim 1, characterized in that, Check valve ZV1 is installed between the compressor outlet and the hydrogen outlet to ensure unidirectional flow of recovered hydrogen and prevent high-pressure hydrogen on the hydrogen outlet side from flowing back into the recovery pipeline and adsorption tower after the compressor stops.

4. A method for using the hydrogen recovery system of claim 2 for adsorption-type hydrogen purification process, characterized in that, Replacing the direct venting method before adsorption tower regeneration with a compressor recovery method includes the following steps: In the pressure equalization step, when the adsorption tower is about to enter the regeneration state, the tower to be regenerated, which has just finished adsorption and is in a high-pressure state, is connected to the working tower, which has completed regeneration and is in a low-pressure state, through a pressure equalization pneumatic angle valve to balance the pressure of the two towers. In the recovery step, the pressure equalization pneumatic angle valve is closed, the working tower enters the adsorption state, the compressor and its pneumatic control angle valve are turned on, the high-purity hydrogen in the tower to be regenerated is extracted and pressurized and then recovered to the hydrogen outlet side of the adsorption hydrogen purification process until the tower to be regenerated reaches the atmospheric pressure state. In the regeneration step, shut down the compressor and its pneumatic control valve, open the regeneration pneumatic control valve, and wait for the regeneration tower to carry out the normal regeneration process. In this system, tower A and tower B alternately perform adsorption and regeneration, enabling continuous and uninterrupted operation of both towers.

5. A method for hydrogen recovery in an adsorption-type hydrogen purification process according to claim 4, characterized in that, During the pressure equalization step, pneumatic angle valves PVA1, PVA2, PVA3, PVB1, PVB2, PVB3, and PV2 and PV3 in the hydrogen recovery process module are all closed, the compressor is stopped, and the pressure equalization pneumatic angle valve PV1 is opened, so that the bottoms of tower A and tower B are connected to each other and gas exchange occurs until the pressure of the two towers reaches equilibrium.

6. A hydrogen recovery method for an adsorption-type hydrogen purification process according to claim 4, characterized in that, In the recovery step, the equalizing pneumatic valve PV1 is closed, while the pneumatic valves PVA1 and PVA3 on the working tower side are open and PVA2 remains closed, keeping the working tower in the adsorption working state. On the regeneration tower side, the pneumatic valves PVB1, PVB3, and PV3 remain closed, while the pneumatic valves PVB2 and PV2 are open. At the same time, the compressor is turned on. The hydrogen with higher purity in the regeneration tower is drawn in by the compressor and pressurized, and then transported to the hydrogen outlet side of the adsorption hydrogen purification process through the check valve ZV1 until the regeneration tower reaches atmospheric pressure.

7. A method for hydrogen recovery in an adsorption-type hydrogen purification process according to claim 4, characterized in that, During the regeneration step, the pneumatic angle valves on the working tower side remain in the same state to continue adsorption and purification; the pneumatic angle valves PVB1, PVB3, and PV2 on the waiting-to-regenerate tower side are closed, while pneumatic angle valves PVB2 and PV3 are open. The waiting-to-regenerate tower is connected to the impurity gas vent through pneumatic angle valves PVB2 and PV3 to carry out the conventional regeneration process. The impurity gas desorbed from the adsorbent is discharged through the impurity gas vent.

8. A method for hydrogen recovery in an adsorption-type hydrogen purification process according to claim 7, characterized in that, The equalization step, recovery step, and regeneration step are executed sequentially under the centralized control of the PLC program, while the working tower maintains the adsorption working state, thereby realizing the alternating and continuous operation of the two towers.

9. A method for hydrogen recovery in an adsorption-type hydrogen purification process according to claim 7, characterized in that, In the recycling step, the high-purity hydrogen that originally needed to be vented from the regeneration tower is recycled to the hydrogen outlet side of the adsorption hydrogen purification process, and then merged with the hydrogen purified by the working tower and returned to the generator, thereby replacing the original method of directly venting the adsorption tower and reducing the hydrogen consumption of the adsorption hydrogen purification process.

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