A hydrogen purification device, hydrogen production system, and method of use

Abstract

This invention relates to the field of hydrogen purification technology, specifically to a hydrogen purification device, a hydrogen production system, and a method of use. A hydrogen purification device includes: an adsorption assembly comprising a first adsorption tower and a second adsorption tower, the first and second adsorption towers being adapted to dehydrate and dry incoming hydrogen gas; and a pipeline assembly comprising a main inlet pipe, a first inlet branch pipe, and a second inlet branch pipe, the main inlet pipe being adapted to allow the flow of hydrogen gas to be dried, one end of the first inlet branch pipe being connected to the main inlet pipe and the other end being connected to the first adsorption tower, and one end of the second inlet branch pipe being connected to the main inlet pipe and the other end being connected to the second adsorption tower. This invention provides a hydrogen purification device, a hydrogen production system, and a method of use to solve the problems of existing hydrogen purification devices, where the drying unit mostly adopts a TSA three-tower process, which involves cumbersome pipeline layout, complex program control, and high cost.

Description

Technical Field

[0001] This invention relates to the field of hydrogen purification technology, specifically to a hydrogen purification device, a hydrogen production system, and a method of using it. Background Technology

[0002] With the implementation of environmental protection policies and the decline in traditional energy reserves, the green hydrogen industry, represented by water electrolysis for hydrogen production, is ushering in a period of rapid development. Among them, alkaline water electrolysis technology has become the mainstream choice for large-scale renewable energy water electrolysis hydrogen production projects due to its advantages of low equipment cost and high process maturity.

[0003] The hydrogen produced by alkaline water electrolysis is separated into hydrogen by a gas-liquid separator to remove most of the alkaline solution and free water before entering a hydrogen purification unit. The hydrogen purification unit comprises two processes: deoxygenation and drying. It utilizes palladium catalyst reaction and molecular sieve adsorption to remove oxygen and water from the hydrogen, ensuring that the oxygen content and dew point of the product hydrogen meet user requirements.

[0004] Existing hydrogen purification devices mostly use the TSA three-tower process in the drying unit, which uses hydrogen as the regeneration gas to regenerate the molecular sieve under high pressure. This has the problem that high pressure is not conducive to desorption, and the three-tower process has a complicated pipeline layout, complex program control, and high cost. Summary of the Invention

[0005] This invention provides a hydrogen purification device, a hydrogen production system, and a method of use to solve the problems of existing hydrogen purification devices, where the drying unit mostly adopts the TSA three-tower process, which has complicated piping layout, complex program control, and high cost.

[0006] In a first aspect, the present invention provides a hydrogen purification apparatus, comprising:

[0007] An adsorption assembly, comprising a first adsorption tower and a second adsorption tower, wherein the first adsorption tower and the second adsorption tower are adapted to dehydrate and dry the incoming hydrogen gas to be dried, respectively. The pipeline assembly further includes an inlet main pipe, a first inlet branch pipe, and a second inlet branch pipe. The inlet main pipe is suitable for flowing hydrogen gas to be dried. One end of the first inlet branch pipe is connected to the inlet main pipe and the other end is connected to the first adsorption tower. One end of the second inlet branch pipe is connected to the inlet main pipe and the other end is connected to the second adsorption tower.

[0008] In the hydrogen production process, the hydrogen gas to be dried in the main inlet pipe enters the first adsorption tower through the first inlet branch pipe for adsorption, while the second adsorption tower is in a regeneration state; or, the hydrogen gas to be dried enters the second adsorption tower through the second inlet branch pipe for adsorption, while the first adsorption tower is in a regeneration state. This two-tower process (when the first adsorption tower is performing adsorption, the second adsorption tower switches between depressurization, regeneration, pressurization, and standby; when the first adsorption tower switches between depressurization, regeneration, pressurization, and standby, the second adsorption tower performs adsorption) achieves a continuous cycle of "one tower adsorption, one tower regeneration," ensuring uninterrupted output of product hydrogen and offering the advantage of a simple structure.

[0009] In one optional embodiment, the piping assembly further includes a first connecting pipe, a first outlet branch pipe, a second outlet branch pipe, and an outlet main pipe. One end of the first connecting pipe is connected to the first inlet branch pipe, and the other end is connected to the second inlet branch pipe. The first connecting pipe is connected to the inlet main pipe. A first inlet control valve and a second inlet control valve are provided on the first connecting pipe. One end of the first outlet branch pipe is connected to the first adsorption tower, and the other end is connected to the outlet main pipe. A first outlet control valve is provided on the first outlet branch pipe. One end of the second outlet branch pipe is connected to the second adsorption tower, and the other end is connected to the outlet main pipe. A second outlet control valve is provided on the second outlet branch pipe.

[0010] In one optional embodiment, a nitrogen flushing assembly is further included. The nitrogen flushing assembly includes a nitrogen inlet pipe and a first heater. The pipe assembly also includes a second connecting pipe. The nitrogen inlet pipe passes through the first heater and is connected to the second connecting pipe. One end of the second connecting pipe is connected to the first outlet branch pipe and the other end is connected to the second outlet branch pipe. A first nitrogen control valve and a second nitrogen control valve are provided on the second connecting pipe.

[0011] In one optional embodiment, the piping assembly further includes a third connecting pipe and a pressure relief pipe, one end of the third connecting pipe being connected to the first intake branch pipe and the other end being connected to the second intake branch pipe, the third connecting pipe being provided with a first exhaust control valve and a second exhaust control valve, and the third connecting pipe being connected to the pressure relief pipe.

[0012] In one optional embodiment, the system further includes a nitrogen recovery assembly and a heat exchange assembly. The heat exchange assembly includes a first heat exchanger. The piping assembly further includes a fourth connecting pipe, one end of which is connected to the first intake branch pipe and the other end of which is connected to the second intake branch pipe. The fourth connecting pipe is provided with a first nitrogen recovery control valve and a second nitrogen recovery control valve. The nitrogen recovery assembly includes a nitrogen recovery pipeline and a filter. The nitrogen recovery pipeline passes through the first heat exchanger of the heat exchange assembly, and the nitrogen recovery pipeline passes through the filter.

[0013] In one optional embodiment, the piping assembly further includes a fifth connecting pipe, one end of which is connected to the first outlet branch pipe and the other end of which is connected to the second outlet branch pipe, and a pressure balance control valve is provided on the fifth connecting pipe.

[0014] In one optional embodiment, the piping assembly further includes a main inlet pipe, a main outlet pipe, a first inlet branch pipe, and a second inlet branch pipe; It also includes a heat exchange assembly and a deoxygenation tower. The heat exchange assembly further includes a second heat exchanger and a second heater. The inlet end of the second heater is adapted to be connected to a raw material hydrogen filter through a second feed branch pipe. The raw material hydrogen filter is adapted to filter the raw material hydrogen. The deoxidation tower is connected to the other end of the second heater. The feed main pipe is provided between the outlet ends of the deoxidation tower and the second heater. The discharge main pipe is provided between the deoxidation tower and the second heat exchanger. The first feed branch pipe is installed through the second heat exchanger. The second feed branch pipe is connected to the first feed branch pipe.

[0015] In one optional embodiment, the system further includes a gas-liquid separator, and the piping assembly includes an inlet manifold, the inlet end of the gas-liquid separator being connected to the outlet manifold, and the outlet end of the gas-liquid separator being connected to the inlet manifold.

[0016] Secondly, the present invention also provides a hydrogen production system, including the hydrogen purification device described above.

[0017] Thirdly, the present invention also provides a method of using a hydrogen purification device, wherein during the hydrogen production process, the hydrogen to be dried in the main inlet pipe enters the first adsorption tower through the first inlet branch pipe for adsorption, and the second adsorption tower is in a regeneration state; or, the hydrogen to be dried enters the second adsorption tower through the second inlet branch pipe for adsorption, and the first adsorption tower is in a regeneration state. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of a hydrogen purification device according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the adsorption component, the first connecting pipe, the second connecting pipe, the third connecting pipe, the fourth connecting pipe, the fifth connecting pipe, the first air inlet branch pipe, the second air inlet branch pipe, the first air outlet branch pipe, and the second air outlet branch pipe in an embodiment of the present invention.

[0020] Explanation of reference numerals in the attached drawings: 1. Piping assembly; 101. Feed main pipe; 102. Discharge main pipe; 103. First feed branch pipe; 104. Air inlet main pipe; 105. First air inlet branch pipe; 106. Second air inlet branch pipe; 107. First air outlet branch pipe; 108. Second air outlet branch pipe; 109. Air outlet main pipe; 110. First connecting pipe; 111. First air inlet control valve; 112. First air outlet control valve; 113. Second connecting pipe; 114. First nitrogen control valve; 115. Third connecting pipe; 116. First exhaust control valve; 117. Pressure relief pipe; 118. Fourth connecting pipe; 119. First nitrogen recovery control valve; 120. Fifth connecting pipe; 121. Pressure balance control valve; 122. Second feed branch pipe; 2. Heat exchange assembly; 201. Second heater; 202. Second heat exchanger; 203. First heat exchanger; 204. Third heat exchanger; 205. First cooling water pipeline; 206. Second cooling water pipeline; 3. Adsorption assembly; 301. First adsorption tower; 302. Second adsorption tower; 4. Gas-liquid separator; 5. Nitrogen flushing assembly; 501. Nitrogen inlet pipeline; 502. First heater; 6. Deoxygenation tower; 7. Nitrogen recovery assembly; 701. Nitrogen recovery pipeline; 8. Analyzer assembly; 9. Raw material hydrogen filter; 10. Hydrogen collection pipeline; 11. Hydrogen emission pipeline; 12. Finished product hydrogen filter. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, 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.

[0022] The following is combined Figures 1 to 2 The following describes embodiments of the present invention.

[0023] According to an embodiment of the present invention, in one aspect, a hydrogen purification apparatus is provided, comprising: Adsorption component 3 includes a first adsorption tower 301 and a second adsorption tower 302, which are adapted to dehydrate and dry the incoming hydrogen gas to be dried, respectively. Piping assembly 1 includes an inlet main pipe 104, a first inlet branch pipe 105, and a second inlet branch pipe 106. The inlet main pipe 104 is suitable for flowing hydrogen gas to be dried. One end of the first inlet branch pipe 105 is connected to the inlet main pipe 104 and the other end is connected to the first adsorption tower 301. One end of the second inlet branch pipe 106 is connected to the inlet main pipe 104 and the other end is connected to the second adsorption tower 302.

[0024] In the hydrogen production process, the hydrogen gas to be dried in the main inlet pipe 104 enters the first adsorption tower 301 through the first inlet branch pipe 105 for adsorption, while the second adsorption tower 302 is in a regeneration state; or, the hydrogen gas to be dried enters the second adsorption tower 302 through the second inlet branch pipe 106 for adsorption, while the first adsorption tower 301 is in a regeneration state. This two-tower process (when the first adsorption tower 301 is adsorbing, the second adsorption tower 302 switches between depressurization, regeneration, pressurization, and standby; when the first adsorption tower 301 switches between depressurization, regeneration, pressurization, and standby, the second adsorption tower 302 adsorbs) achieves a continuous cycle of "one tower adsorption, one tower regeneration," ensuring uninterrupted output of product hydrogen. It has the advantages of simple structure and reduced construction and operating costs. In this embodiment, the first inlet branch pipe 105 is located at the bottom of the first adsorption tower 301, and the second inlet branch pipe 106 is located at the bottom of the second adsorption tower 302.

[0025] In one embodiment, such as Figure 1 , Figure 2 As shown, the pipeline assembly 1 also includes a first connecting pipeline 110, a first outlet branch pipe 107, a second outlet branch pipe 108, and an outlet main pipe 109. One end of the first connecting pipeline 110 is connected to the first inlet branch pipe 105, and the other end is connected to the second inlet branch pipe 106. The first connecting pipeline 110 is connected to the inlet main pipe 104. A first inlet control valve 111 and a second inlet control valve are provided on the first connecting pipeline 110. One end of the first outlet branch pipe 107 is connected to the first adsorption tower 301, and the other end is connected to the outlet main pipe 109. A first outlet control valve 112 is provided on the first outlet branch pipe 107. One end of the second outlet branch pipe 108 is connected to the second adsorption tower 302, and the other end is connected to the outlet main pipe 109. A second outlet control valve is provided on the second outlet branch pipe 108.

[0026] In this embodiment, as Figure 1 , Figure 2 As shown, the connection between the intake manifold 104 and the first connecting pipe 110 is located in the middle of the first connecting pipe 110. Gaseous hydrogen in the intake manifold 104 enters the first connecting pipe 110 and then enters the first intake branch pipe 105 or the second intake branch pipe 106. A first intake control valve 111 is provided on the first connecting pipe 110 between the intake manifold 104 and the first intake branch pipe 105, and a second intake control valve is provided on the first connecting pipe 110 between the intake manifold 104 and the second intake branch pipe 106.

[0027] In one embodiment, such as Figure 1 , Figure 2 As shown, it also includes a nitrogen flushing assembly 5, which includes a nitrogen inlet pipe 501 and a first heater 502. The pipe assembly 1 also includes a second connecting pipe 113. The nitrogen inlet pipe 501 passes through the first heater 502 and is connected to the second connecting pipe 113. One end of the second connecting pipe 113 is connected to the first outlet branch pipe 107 and the other end is connected to the second outlet branch pipe 108. The second connecting pipe 113 is provided with a first nitrogen control valve 114 and a second nitrogen control valve.

[0028] In this embodiment, as Figure 1 , Figure 2 As shown, nitrogen in nitrogen inlet pipe 501 is heated by first heater 502 and then enters second connecting pipe 113, and is delivered by second connecting pipe 113 to first outlet branch pipe 107 or second outlet branch pipe 108. A first nitrogen control valve 114 is provided on second connecting pipe 113 between nitrogen inlet pipe 501 and first outlet branch pipe 107, and a second nitrogen control valve is provided on second connecting pipe 113 between nitrogen inlet pipe 501 and second outlet branch pipe 108.

[0029] In one embodiment, such as Figure 1 , Figure 2 As shown, the piping assembly 1 also includes a third connecting pipe 115 and a pressure relief pipe 117. One end of the third connecting pipe 115 is connected to the first intake branch pipe 105, and the other end is connected to the second intake branch pipe 106. A first exhaust control valve 116 and a second exhaust control valve are provided on the third connecting pipe 115. The third connecting pipe 115 is connected to the pressure relief pipe 117. In this embodiment, as... Figure 1 , Figure 2As shown, the gas in the first intake branch pipe 105 or the second intake branch pipe 106 is discharged to the pressure relief pipe 117 via the third connecting pipe 115, and then discharged into the atmosphere through the pressure relief pipe 117 to reduce the pressure in the first adsorption tower 301 or the second adsorption tower 302. It should be noted that a first exhaust control valve 116 is provided on the third connecting pipe 115 between the first intake branch pipe 105 and the pressure relief pipe 117, and a second exhaust control valve is provided on the third connecting pipe 115 between the second intake branch pipe 106 and the pressure relief pipe 117.

[0030] In one embodiment, such as Figure 1 , Figure 2 As shown, the system also includes a nitrogen recovery assembly 7 and a heat exchange assembly 2. The heat exchange assembly 2 includes a first heat exchanger 203. The piping assembly 1 also includes a fourth connecting pipe 118. One end of the fourth connecting pipe 118 is connected to the first inlet branch pipe 105, and the other end is connected to the second inlet branch pipe 106. The fourth connecting pipe 118 is equipped with a first nitrogen recovery control valve 119 and a second nitrogen recovery control valve. The nitrogen recovery assembly 7 includes a nitrogen recovery pipe 701 and a filter 702. The nitrogen recovery pipe 701 passes through the first heat exchanger 203 of the heat exchange assembly 2, and passes through the filter 702. Gas in the first inlet branch pipe 105 or the second inlet branch pipe 106 enters the nitrogen recovery pipe 701 through the fourth connecting pipe 118, and dust and other substances contained in the nitrogen are removed by the filter 702, thereby realizing nitrogen recovery. It should be noted that a first nitrogen recovery control valve 119 is provided on the fourth connecting pipe 118 between the first intake branch pipe 105 and the nitrogen recovery pipe 701, and a second nitrogen recovery control valve is provided on the fourth connecting pipe 118 between the second intake branch pipe 106 and the nitrogen recovery pipe 701.

[0031] In one embodiment, such as Figure 1 , Figure 2 As shown, the piping assembly 1 also includes a fifth connecting pipe 120, one end of which is connected to the first outlet branch pipe 107 and the other end of which is connected to the second outlet branch pipe 108. A pressure balance control valve 121 is provided on the fifth connecting pipe 120. Pressure balance in the first adsorption tower 301 and the second adsorption tower 302 is achieved through the fifth connecting pipe 120 and the pressure balance control valve 121.

[0032] In this embodiment, as Figure 1 , Figure 2As shown, the first connecting pipe 110, the third connecting pipe 115, and the fourth connecting pipe 118 are all located at the bottom of the first adsorption tower 301 and the second adsorption tower 302, and the height of the fourth connecting pipe 118 is lower than that of the first connecting pipe 110, and the height of the first connecting pipe 110 is lower than that of the third connecting pipe 115. The second connecting pipe 113 and the fifth connecting pipe 120 are both located at the top of the first adsorption tower 301 and the second adsorption tower 302, and the height of the second connecting pipe 113 is higher than that of the fifth connecting pipe 120.

[0033] In this embodiment, as Figure 1 , Figure 2 As shown, the heat exchange assembly 2 also includes a third heat exchanger 204. The discharge main pipe 102 passes through the third heat exchanger 204. The third heat exchanger 204 is located downstream of the second heat exchanger 202 (in this embodiment, downstream means that hydrogen first flows through the second heat exchanger 202 and then through the third heat exchanger 204). A first cooling water pipe 205 is also provided at the third heat exchanger 204, and a second cooling water pipe 206 is also provided at the first heat exchanger 203.

[0034] In one embodiment, such as Figure 1 , Figure 2 As shown, the pipeline assembly 1 also includes a feed main pipe 101, a discharge main pipe 102, a first feed branch pipe 103, and a second feed branch pipe 122; it also includes a heat exchange assembly 2 and a deoxygenation tower 6, including a second heat exchanger 202 and a second heater 201. The inlet end of the second heater 201 is adapted to be connected to a raw material hydrogen filter 9 through the second feed branch pipe 122, and the raw material hydrogen filter 9 is adapted to filter the hydrogen to be deoxygenated; the other end of the deoxygenation tower 6 is connected to the second heater 201, and a feed main pipe 101 is provided between the outlet ends of the deoxygenation tower 6 and the second heater 201. A discharge main pipe 102 is provided between the deoxygenation tower 6 and the second heat exchanger 202. The first feed branch pipe 103 is disposed through the second heat exchanger 202, and the second feed branch pipe 122 is connected to the first feed branch pipe 103. In this embodiment, the inlet and outlet of the first feed branch pipe 103 are respectively connected to the second feed branch pipe 122.

[0035] The hydrogen feedstock first enters the second heater 201 through the second feed branch pipe 122. After being heated by the second heater 201, it enters the deoxidation tower 6 through the feed main pipe 101. The deoxidized hydrogen gas to be dried in the deoxidation tower 6 enters the discharge main pipe 102. The temperature in the deoxidation tower 6 is slowly increased to raise the temperature of the hydrogen gas entering the discharge main pipe 102. The hydrogen gas to be dried in the discharge main pipe 102 enters the second heat exchanger 202. After the temperature in the second heat exchanger 202 reaches the temperature required to heat the hydrogen feedstock to the temperature required to reach the deoxidation tower 6 (activation temperature), the second heater 201 is turned off. The hydrogen feedstock then enters the second heat exchanger 202 through the first feed branch pipe 103. The hydrogen feedstock exchanges heat with the hydrogen gas to be dried in the discharge pipe in the second heat exchanger 202. The above setup allows the heat of the hydrogen to be dried in the discharge main pipe 102 to be exchanged with the hydrogen feedstock through the second heat exchanger 202, eliminating the need for the second heater 201 and reducing energy consumption. At the same time, the hydrogen feedstock can absorb the heat of the hydrogen to be dried to improve energy utilization.

[0036] In one embodiment, such as Figure 1 , Figure 2 As shown, the system also includes a gas-liquid separator 4, and the piping assembly 1 includes an inlet manifold 104. The inlet end of the gas-liquid separator 4 is connected to the outlet manifold 102, and the outlet end of the gas-liquid separator 4 is connected to the inlet manifold 104. After passing through the second heat exchanger 202, the outlet manifold 102 enters the gas-liquid separator 4, where the gaseous hydrogen and liquid hydrogen are separated. The separated gaseous hydrogen then enters the inlet manifold 104.

[0037] According to an embodiment of the present invention, another aspect provides a hydrogen production system, including the hydrogen purification device described above.

[0038] A method of using a hydrogen purification device includes the following steps: (1) Deoxygenation, heat recovery and separation stage After being filtered by the raw material hydrogen filter 9, the raw material hydrogen enters the second heater 201 through the second feed branch pipe 122. The second heater 201 heats the raw hydrogen to about 100°C. The heated raw material hydrogen enters the deoxygenation tower 6 through the feed main pipe 101. Under the action of the palladium catalyst, hydrogen and oxygen combine to form water. The hot hydrogen gas (to be dried) after being catalytically deoxygenated in the deoxygenation tower 6 enters the second heat exchanger 202 through the discharge main pipe 102 to recover heat. Then, it passes through the third heat exchanger 204 and is cooled to about 15°C by the chilled water in the first cooling water pipe 205. When the outlet temperature of deoxygenation tower 6 (i.e., the temperature of hot hydrogen gas in the discharge main pipe 102) reaches about 140~160℃, the hydrogen feedstock is switched to enter the second heat exchanger 202 through the first feed branch pipe 103 and exchange heat with the high-temperature hydrogen gas to be dried from deoxygenation tower 6. The medium-temperature gas after heat recovery then enters the second heater 201. At this stage, the temperature of the feedstock hydrogen after heat exchange has reached the activation temperature of the deoxygenation catalyst, so the second heater 201 will be basically in a shutdown state, saving energy and reducing consumption. It can also reduce the load on the downstream third heat exchanger 204 and reduce the circulation volume of chilled water. The raw hydrogen gas processed through the above steps enters the gas-liquid separator 4 to separate the free water in it before entering the subsequent dehydration system; (2) Dehydration and drying stage It consists of five steps: adsorption, depressurization, regeneration, pressurization, and standby switching. Adsorption Steps: Hydrogen gas to be dried at 15°C and 1.6MPa from the gas-liquid separator 4 enters the main inlet pipe 104 (at this time, only the first inlet control valve 111 and the first outlet control valve 112 are open, and all other valves are closed). The hydrogen gas to be dried enters the bottom of the first adsorption tower 301 along the main inlet pipe 104, the first connecting pipe 110, and the first inlet branch pipe 105. It flows from bottom to top through the molecular sieve bed in the first adsorption tower 301. Moisture is adsorbed by the polar sites in the molecular sieve channels. The qualified product hydrogen gas (dew point ≤ -70°C) after dehydration flows from the top of the tower through the first outlet branch pipe 107 and the main outlet pipe 109. The hydrogen gas in the main outlet pipe 109 is sent to the user end after passing inspection. At the same time, 5%~10% of the qualified hydrogen gas at the top of the first adsorption tower 301 is reserved for the "pressure equalization and pressurization" of the subsequent second adsorption tower 302 (to reduce hydrogen emission loss). Depressurization step: Reduce the pressure of the first adsorption tower 301, which has completed adsorption, from 1.6 MPa to close to the nitrogen purging pressure of 0.6 MPa, so that the water adsorbed by the molecular sieve is desorbed, in preparation for nitrogen purging. When the adsorption time of the first adsorption tower 301 reaches the preset time and the molecular sieve is close to saturation, the first inlet control valve 111 and the first outlet control valve 112 are closed to stop adsorption. Slowly open the first exhaust control valve 116 located on the third connecting pipe 115, and control the pressure relief rate (≤0.02MPa / s) by throttling the valve to avoid the molecular sieve bed being disturbed or pulverized due to the impact of the sudden pressure drop. During this process, the molecular sieve desorbs some of the previously adsorbed water due to "pressure reduction → adsorption capacity decrease", and is released into the external environment through the flame arrester along with the residual hydrogen from the pressure relief pipe 117. Regeneration Step: At the beginning of the regeneration step (end of the depressurization step), open the first nitrogen control valve 114 and the first nitrogen recovery control valve 119, and close the first exhaust control valve 116. Low-pressure nitrogen of 0.6MPa is introduced into the nitrogen inlet pipeline 501 for purging. The nitrogen enters from the top of the first adsorption tower 301 through the second connecting pipeline 113 and the first outlet branch pipe 107, and washes the molecular sieve bed from top to bottom, further removing residual moisture. The "nitrogen + moisture + trace hydrogen" mixture after purging is recovered through the first inlet branch pipe 105, the fourth connecting pipeline 118, and the nitrogen recovery pipeline 701. (3) Regeneration stage (including heating stage, cold blowing stage and pressurization stage) Heating stage: Low-pressure nitrogen gas of 0.6MPa is heated to 220°C by the first heater 502 and then enters the first adsorption tower 301. The temperature inside the first adsorption tower 301 gradually rises, and the water adsorbed on the molecular sieve is further desorbed. When the bottom temperature of the first adsorption tower 301 reaches 150°C, the first heater 502 automatically stops heating, and the heating stage ends. Cold blowing stage: After the first heater 502 stops heating, low-pressure nitrogen continues to flow into the first adsorption tower 301 through the original pipeline to cool down the first adsorption tower 301. When the bottom temperature of the first adsorption tower 301 reaches 50°C, the cold blowing ends and regeneration is completed. Pressurization Stage: After nitrogen purging of the first adsorption tower 301 is completed (the dew point of the exhaust gas is detected to be ≤-70℃, indicating that moisture has been completely desorbed), close the first nitrogen control valve 114 and the first nitrogen recovery control valve 119 of the first adsorption tower 301; open the pressure balance control valve 121 on the fifth connecting pipeline 120 between the first adsorption tower 301 and the second adsorption tower 302 (at this time, the second adsorption tower 302 is in the final stage of adsorption, with a pressure of 1.6MPa), and slowly flush the qualified hydrogen from the top of the second adsorption tower 302 into the first adsorption tower 301, so that the pressure of the first adsorption tower 301 is reduced from the pressure of the second adsorption tower 301 to the pressure of the second adsorption tower 302. The pressure is increased from 0.6 MPa to 1.0-1.3 MPa (equalization pressure, approximately 60%-80% of the adsorption pressure). During this process, hydrogen is recovered, reducing waste. After equalization, the pressure balance control valve 121 is closed, and the first outlet control valve 112 of the first adsorption tower 301 is opened (high-pressure hydrogen is supplied through the outlet manifold 109), further increasing the pressure of the first adsorption tower 301 to 1.6 MPa (consistent with the adsorption pressure). The pressure increase rate is controlled at ≤0.03 MPa / s. After the pressure increase is completed, the first adsorption tower 301 is in a "waiting to adsorb" state, waiting for the second adsorption tower 302 to complete adsorption before switching. After regeneration, the pressure in the first adsorption tower 301 increases from 0.6 MPa to 1.6 MPa to prepare for the next round of adsorption and avoid direct impact from high pressure. Standby switching steps: When the adsorption of the second adsorption tower 302 reaches saturation, repeat the above steps: the second adsorption tower 302 enters the "depressurization → regeneration → pressurization" process, and the first adsorption tower 301 simultaneously opens the first inlet control valve 111 and the first outlet control valve 112 to enter the adsorption stage, realizing the continuous cycle of "one tower adsorption and one tower regeneration" to ensure uninterrupted output of hydrogen.

[0039] It should be noted that the above steps only describe the switching of the first adsorption tower 301 for adsorption, depressurization, regeneration, pressurization, and standby. In actual operation, when the first adsorption tower 301 is performing adsorption, the second adsorption tower 302 is performing depressurization, regeneration, pressurization, and standby. When the first adsorption tower 301 is performing depressurization, regeneration, pressurization, and standby, the second adsorption tower 302 is performing adsorption, thereby ensuring that there is always produced hydrogen flowing in the gas outlet main pipe 109.

[0040] In this embodiment, as Figure 1 , Figure 2 As shown, hydrogen entering the main outlet pipe 109 is processed by an analyzer group 8 (oxygen analyzer, nitrogen analyzer, and dew point analyzer). A finished hydrogen filter 12 is installed upstream of the analyzer group 8 and is located on the main outlet pipe 109. The analyzer group 8 is connected to the hydrogen collection pipeline 10. The hydrogen quality is tested, and qualified hydrogen is collected or reused via the hydrogen collection pipeline 10. Unqualified hydrogen is discharged or collected via the hydrogen emission pipeline 11. In this embodiment, the purification process includes two stages: deoxygenation and drying. The hydrogen before entering the deoxygenation tower 6 is the hydrogen to be deoxygenated, and the hydrogen after deoxygenation in the deoxygenation tower 6 is the hydrogen to be dried.

[0041] In this embodiment, as Figure 1 , Figure 2 As shown, the nitrogen flowing out through the nitrogen recovery pipeline 701 passes through the first heat exchanger 203 and exchanges heat with the second cooling water pipeline 206. After the temperature drops to room temperature, it is sent out and can be used as stripping nitrogen in a low-temperature methanol washing device or as purging nitrogen for the system.

[0042] In this embodiment, the parameters in each step are as follows: Raw material hydrogen operating parameters: 40℃, 1.6MPaG, hydrogen purity ≥99.8% (v), oxygen content ≤0.2% (v), nitrogen content ≤5ppm; Product hydrogen operating parameters: ambient temperature, 1.5 MPaG, hydrogen purity ≥ 99.999% (v), oxygen content ≤ 5 ppm, nitrogen content ≤ 5 ppm, dew point ≤ -70℃; Low-pressure nitrogen operating conditions: ambient temperature, 0.6 MPaG, nitrogen purity ≥ 99.99% (v), oxygen content ≤ 5 ppm, dew point ≤ -70℃, oil-free and dust-free low-pressure nitrogen; Chilled water, supply temperature 7℃, return temperature approximately 12℃, supply pressure approximately 0.35 MPa (G).

[0043] The hydrogen purification device provided by the present invention has the following advantages: (1) It adopts a two-tower process (when the first adsorption tower 301 is performing adsorption, the second adsorption tower 302 is switching between depressurization, regeneration, pressurization, and standby; when the first adsorption tower 301 is switching between depressurization, regeneration, pressurization, and standby, the second adsorption tower 302 is performing adsorption), realizing a continuous cycle of "one tower adsorption and one tower regeneration", ensuring uninterrupted output of product hydrogen; (2) The hydrogen raw material first enters the second heater 201 through the second feed branch pipe 122, and after being heated by the second heater 201, it enters the feed main pipe 101. The deoxygenated hydrogen gas enters the deoxygenation tower 6 and then flows into the discharge main pipe 102. The temperature inside the deoxygenation tower 6 is gradually increased to raise the temperature of the hydrogen gas entering the discharge main pipe 102. The hydrogen gas in the discharge main pipe 102 then enters the second heat exchanger 202. Once the temperature in the second heat exchanger 202 reaches the temperature required to heat the hydrogen feedstock to the temperature required to reach the deoxygenation tower 6 (activation temperature), the second heater 201 is turned off. The hydrogen feedstock then enters the second heat exchanger 202 through the first feed branch pipe 103, where it exchanges heat with the hydrogen gas in the discharge pipe. The above setup allows the heat of the hydrogen to be dried in the main outlet pipe 102 to be exchanged with the hydrogen raw material through the second heat exchanger 202, eliminating the need for the second heater 201 and reducing energy consumption. At the same time, the hydrogen raw material can absorb the heat of the hydrogen to be dried to improve energy utilization. (3) Low-pressure nitrogen is used to regenerate the molecular sieve. Compared with the existing method of using hydrogen as the regeneration gas to regenerate the molecular sieve under high pressure, this avoids the problem that high pressure is not conducive to desorption, making desorption more complete and improving the effect and efficiency of molecular sieve regeneration. (4) The cooling medium used in the first cooling water pipeline 205 is 7°C chilled water. Compared with conventional 32℃ circulating cooling water, the temperature of the raw material crude hydrogen entering the first adsorption tower 301 and the second adsorption tower 302 can be further reduced, thereby separating more free water in the gas-liquid separator 4, reducing the load of subsequent entry into the first adsorption tower 301 or the second adsorption tower 302, thereby reducing the molecular sieve filling amount and optimizing the equipment size; (5) The hydrogen in the discharge main pipe 102 first exchanges heat with the hydrogen raw material in the second heat exchanger 202, and then exchanges heat with the cooling water in the first cooling water pipeline 205 in the third heat exchanger 204, realizing the cascade utilization of heat and having the advantage of high energy utilization rate.

[0044] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A hydrogen purification device, characterized in that, include: The adsorption component (3) includes a first adsorption tower (301) and a second adsorption tower (302), wherein the first adsorption tower (301) and the second adsorption tower (302) are adapted to dehydrate and dry the incoming hydrogen gas, respectively. The pipeline assembly (1) includes an inlet main pipe (104), a first inlet branch pipe (105), and a second inlet branch pipe (106). The inlet main pipe (104) is suitable for flowing hydrogen gas to be dried. One end of the first inlet branch pipe (105) is connected to the inlet main pipe (104), and the other end is connected to the first adsorption tower (301). One end of the second inlet branch pipe (106) is connected to the inlet main pipe (104), and the other end is connected to the second adsorption tower (302).

2. The hydrogen purification apparatus according to claim 1, characterized in that, The piping assembly (1) further includes a first connecting pipe (110), a first outlet branch pipe (107), a second outlet branch pipe (108), and an outlet main pipe (109). One end of the first connecting pipe (110) is connected to the first inlet branch pipe (105), and the other end is connected to the second inlet branch pipe (106). The first connecting pipe (110) is connected to the inlet main pipe (104). A first inlet control valve is provided on the first connecting pipe (110). (111) and a second inlet control valve, one end of the first outlet branch pipe (107) is connected to the first adsorption tower (301) and the other end is connected to the outlet main pipe (109), the first outlet branch pipe (107) is provided with a first outlet control valve (112), one end of the second outlet branch pipe (108) is connected to the second adsorption tower (302) and the other end is connected to the outlet main pipe (109), the second outlet branch pipe (108) is provided with a second outlet control valve.

3. The hydrogen purification apparatus according to claim 2, characterized in that, It also includes a nitrogen flushing assembly (5), which includes a nitrogen inlet pipe (501) and a first heater (502). The pipe assembly (1) also includes a second connecting pipe (113). The nitrogen inlet pipe (501) passes through the first heater (502) and is connected to the second connecting pipe (113). One end of the second connecting pipe (113) is connected to the first outlet branch pipe (107) and the other end is connected to the second outlet branch pipe (108). The second connecting pipe (113) is provided with a first nitrogen control valve (114) and a second nitrogen control valve.

4. The hydrogen purification apparatus according to claim 2, characterized in that, The pipeline assembly (1) further includes a third connecting pipeline (115) and a pressure relief pipeline (117). One end of the third connecting pipeline (115) is connected to the first intake branch pipe (105), and the other end is connected to the second intake branch pipe (106). The third connecting pipeline (115) is provided with a first exhaust control valve (116) and a second exhaust control valve. The third connecting pipeline (115) is connected to the pressure relief pipeline (117).

5. The hydrogen purification apparatus according to claim 2, characterized in that, It also includes a nitrogen recovery assembly (7) and a heat exchange assembly (2). The heat exchange assembly (2) includes a first heat exchanger (203). The pipeline assembly (1) also includes a fourth connecting pipeline (118). One end of the fourth connecting pipeline (118) is connected to the first air inlet branch pipe (105), and the other end is connected to the second air inlet branch pipe (106). The fourth connecting pipeline (118) is provided with a first nitrogen recovery control valve (119) and a second nitrogen recovery control valve. The nitrogen recovery assembly (7) includes a nitrogen recovery pipeline (701) and a filter (702). The nitrogen recovery pipeline (701) passes through the first heat exchanger (203) of the heat exchange assembly (2), and the nitrogen recovery pipeline (701) passes through the filter (702).

6. The hydrogen purification apparatus according to claim 2, characterized in that, The pipeline assembly (1) further includes a fifth connecting pipeline (120), one end of which is connected to the first gas outlet branch pipe (107) and the other end is connected to the second gas outlet branch pipe (108). A pressure balance control valve (121) is provided on the fifth connecting pipeline (120).

7. The hydrogen purification apparatus according to claim 1, characterized in that, The pipeline assembly (1) also includes a feed main pipe (101), a discharge main pipe (102), a first feed branch pipe (103), and a second feed branch pipe (122). It also includes a heat exchange assembly (2) and a deoxygenation tower (6). The heat exchange assembly (2) further includes a second heat exchanger (202) and a second heater (201). The inlet end of the second heater (201) is adapted to be connected to a raw material hydrogen filter (9) through a second feed branch pipe (122). The raw material hydrogen filter (9) is adapted to filter the raw material hydrogen. The deoxidation tower (6) is connected to the other end of the second heater (201). The feed main pipe (101) is provided between the outlet ends of the deoxidation tower (6) and the second heater (201). The discharge main pipe (102) is provided between the deoxidation tower (6) and the second heat exchanger (202). The first feed branch pipe (103) is provided through the second heat exchanger (202). The second feed branch pipe (122) is connected to the first feed branch pipe (103).

8. The hydrogen purification apparatus according to claim 7, characterized in that, It also includes a gas-liquid separator (4), and the pipeline assembly (1) also includes an air inlet manifold (104). The inlet end of the gas-liquid separator (4) is connected to the discharge manifold (102), and the outlet end of the gas-liquid separator (4) is connected to the air inlet manifold (104).

9. A hydrogen production system, characterized in that, Includes the hydrogen purification apparatus according to any one of claims 1-8.

10. A method of using a hydrogen purification device, for using the hydrogen purification device according to claim 1, characterized in that, During the hydrogen production process, the hydrogen gas to be dried in the main inlet pipe (104) enters the first adsorption tower (301) through the first inlet branch pipe (105) for adsorption, and the second adsorption tower (302) is in a regeneration state; or, the hydrogen gas to be dried enters the second adsorption tower (302) through the second inlet branch pipe (106) for adsorption, and the first adsorption tower (301) is in a regeneration state.

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