Fuel cell hydrogen recovery system and method
By designing a fuel cell hydrogen recovery system and using technologies such as system water separator and solenoid valve, efficient separation, drying and storage of hydrogen is achieved, solving the problem of mixing and explosion of hydrogen with tail exhaust air during hydrogen recovery, reducing the risk of The cost of hydrogen has realized the recycling of hydrogen.
Patent Information
- Application Number
- CN202411500115.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-25
- Publication Date
- 2025-01-03
AI Technical Summary
During the hydrogen recovery process of existing fuel cell systems, hydrogen is mixed with the tail exhaust air, resulting in complex gas composition, difficult to control hydrogen concentration, easy to cause explosion, and hydrogen cannot completely return to the anode inlet, and hydrogen is expensive, resulting in difficulty in recycling. .
A fuel cell hydrogen recovery system is designed, including hydrogen supply module, air supply module and stack module. It separates hydrogen from water through the system water separator, drys and stores hydrogen to avoid mixing hydrogen with tail exhaust air, and uses solenoid valves and The hydrogen sensor controls the circulation of hydrogen to achieve no combustion and emission recovery of hydrogen.
It realizes efficient recycling and storage of hydrogen, avoids the risk of hydrogen explosion, reduces hydrogen costs, ensures hydrogen recycling, and increases hydrogen concentration. It is suitable for hydrogen management under emergency shutdown and other operating conditions.
Smart Images
Figure CN119252996A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of fuel cells, and in particular to a fuel cell hydrogen recovery system and method. Background Art
[0002] The hydrogen in the existing fuel cell system is mixed with the exhaust air, and the gas composition is complex. In emergency shutdown or other working conditions, the fuel cell system emits too much hydrogen. In some usage scenarios, there are strict requirements for hydrogen emissions to avoid hydrogen accumulation and explosion caused by excessive concentration. Therefore, the current fuel cell system is used in a ventilated state in the whole vehicle to avoid this problem. However, in some scenarios, the space is closed or the airflow is not smooth, which is likely to cause an explosion. Therefore, for some scenarios, hydrogen emissions must be strictly controlled.
[0003] The existing fuel cell system and patents mainly rely on circulating pumps and related control valves to recover hydrogen. The hydrogen at the anode outlet is mixed with the hydrogen from the hydrogen supply system through the circulating pump and enters the anode inlet of the fuel cell system. Since the anode produces water, hydrogen will still be discharged along with the water during the drainage process of the fuel cell system. In actual use, the hydrogen concentration at the tail outlet can be directly detected by a hydrogen concentration sensor. Therefore, the current fuel cell system cannot guarantee that hydrogen can completely flow back to the anode inlet.
[0004] The existing patents use combustion to consume the hydrogen in the tail exhaust, but the concentration range of hydrogen explosion is very large. In the process of collecting hydrogen, it is difficult to control the hydrogen concentration and it is very easy to explode. Therefore, it is not recommended to consume hydrogen by combustion.
[0005] In the current market environment, the market is very sensitive to the price of hydrogen. The high price of hydrogen has led to slow development of the hydrogen energy industry. As the market slowly recovers, the recycling of hydrogen remains a major issue. Summary of the invention
[0006] In order to overcome the deficiencies of the prior art, the present invention provides a fuel cell hydrogen recovery system and method.
[0007] To achieve the above purpose, a fuel cell hydrogen recovery system is designed, including a hydrogen supply module, an air supply module, and a stack module. The anode outlet of the stack module is connected to a system water distributor, and the outlets of the system water distributor are respectively connected to the hydrogen supply module and the hydrogen recovery module. The hydrogen recovery module includes a shell, a hydrogen drying area, an exhaust water distribution area, and an exhaust hydrogen storage bottle. The outlet of the system water distributor is connected to a water inlet drain valve through a hydrogen inlet pipe, and the outlet of the water inlet drain valve is connected to the inlet of the exhaust water distribution area. The outlet of the exhaust water distribution area is divided into two paths and respectively connected to a water outlet drain valve and a hydrogen drying area. The outlet of the water outlet drain valve is connected to a drain port, and the outlet of the hydrogen drying area is connected to the exhaust hydrogen storage bottle through a hydrogen bottle mouth solenoid valve.
[0008] In the air supply module, the outlet of the air compressor is connected to the purge pipe, and the purge pipe is connected to the hydrogen drying area and the exhaust water separation area in the shell through the first purge solenoid valve. The shell is also connected to the purge outlet through the second purge solenoid valve.
[0009] The shell is provided with a frame, and a support body is provided in the frame. The upper part of the support body is a hydrogen drying area, and the lower part of the support body is an exhaust water separation area. The support body includes several layers of support plates connected in a serpentine shape, and a gas passage hole is provided on the surface of the support plate at the serpentine turning point.
[0010] A plurality of drainage baffles are arranged in the support body of the exhaust water separation zone, and the shape of the drainage baffles is a broken line.
[0011] Baffles are arranged at both ends of the support body in the hydrogen drying area, a desiccant is arranged between the two baffles, and a plurality of gas passing holes are arranged on the baffles.
[0012] A liquid level meter is arranged in the exhaust water separation area; and a hydrogen sensor is arranged in the shell.
[0013] The anode inlet of the stack module is connected to a hydrogen source via a hydrogen supply module.
[0014] The air supply module includes an air compressor and a flow meter. The cathode inlet of the stack module is connected to the air compressor. The air compressor is connected to the air source through an air pipe, and the air pipe is provided with a flow meter.
[0015] To achieve the above purpose, a method for a fuel cell hydrogen recovery system is designed, including the following modes: S1, normal operation mode: During the operation of the stack module, hydrogen and water enter the system water separator from the anode outlet, part of the hydrogen and water vapor enter the hydrogen supply module, and the other part of the hydrogen and water vapor pass through the hydrogen inlet pipe and the water inlet drain valve to reach the exhaust water separation area. In the exhaust water separation area, the water vapor is further separated, and the separated hydrogen enters the hydrogen drying area to perform the final drying on the residual water vapor in the hydrogen. The dried hydrogen passes through the hydrogen bottle mouth solenoid valve and enters the exhaust hydrogen storage bottle. The water separated in the exhaust water separation area is discharged through the water outlet drain valve; S2, hydrogen dryer regeneration mode: the stack module stops running, and the air compressor of the air supply module continues to run. The compressed dry air passes through the purge pipe and the purge solenoid valve and enters the hydrogen drying area and the exhaust water separation area respectively to purge the moisture dry. The purged gas is discharged from the purge outlet and the drain outlet.
[0016] In the mode S1, the water inlet and outlet valves and the hydrogen bottle mouth solenoid valve are opened to ensure that hydrogen can be smoothly separated, dried and stored; the first purge solenoid valve and the second purge solenoid valve are both in a closed state to prevent hydrogen from leaking through other channels.
[0017] In the described mode S2, purge solenoid valve 1, purge solenoid valve 2, and water outlet drain valve are opened to ensure gas circulation; the water inlet drain valve and hydrogen bottle mouth solenoid valve are closed to prevent the purge gas from entering the exhaust hydrogen storage bottle and the system water distributor.
[0018] It also includes mode S3, hydrogen leakage detection mode: when the hydrogen concentration sensor detects the presence of a certain amount of hydrogen in the hydrogen recovery module, the system reduces power or stops running and waits for maintenance personnel to inspect.
[0019] Compared with the prior art, the present invention has the following beneficial effects: 1. Recover the hydrogen discharged from the water distributor outlet of the fuel cell system. The hydrogen at this outlet is composed of hydrogen except for a large amount of water. This avoids the mixing of hydrogen and air at the tail outlet in the existing fuel cell system solution, resulting in complex gas composition and difficult gas control.
[0020] 2. Hydrogen can be recycled into hydrogen bottles through water separation, hydrogen drying, and non-combustion and non-emission of hydrogen, thus solving the explosion risk in the process of burning and consuming hydrogen in the existing patents.
[0021] 3. The hydrogen concentration in the obtained hydrogen bottle is relatively high, and the hydrogen bottle can be used in other scenarios, which can realize the recycling of hydrogen and reduce the cost of using hydrogen. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is a system schematic diagram of the present invention.
[0023] Figure 2 This is a schematic diagram of the external interface of the hydrogen recovery module of the present invention.
[0024] Figure 3 It is a schematic diagram of the internal structure of the hydrogen recovery module of the present invention.
[0025] Figure 4 This is a schematic diagram of the structure of the hydrogen recovery module of the present invention after removing the frame.
[0026] Figure 5 It is a schematic structural diagram of the exhaust water separation area of the present invention.
[0027] Figure 6 It is a top view of the exhaust water separation area of the present invention.
[0028] Figure 7 It is a schematic diagram of the gas flow in the exhaust water separation area of the present invention.
[0029] Figure 8 It is a schematic structural diagram of the hydrogen drying zone of the present invention.
[0030] Fig. 9 Schematic diagram of the gas flow in the hydrogen drying zone of the present invention.
[0031] Fig.10 Schematic diagram of gas flow in normal operation mode of the present invention.
[0032] Fig.11 Schematic diagram of gas flow in the regeneration mode of the hydrogen dryer of the present invention. DETAILED DESCRIPTION
[0033] The present invention will be further described below with reference to the accompanying drawings.
[0034] like Figures 1 to 11 As shown, the anode outlet of the stack module 1 is connected to the system water separator 4, and the outlets of the system water separator 4 are respectively connected to the hydrogen supply module 2 and the hydrogen recovery module 5. The hydrogen recovery module 5 includes a shell 5-1, a hydrogen drying area 5-2, an exhaust water separation area 5-3, and an exhaust hydrogen storage bottle 5-4. The outlet of the system water separator 4 is connected to the water inlet and drain valve 5-6 through a hydrogen inlet pipe 5-5, and the outlet of the water inlet and drain valve 5-6 is connected to the inlet of the exhaust water separation area 5-3. The outlet of the exhaust water separation area 5-3 is divided into two ways and respectively connected to the water outlet and drain valve 5-7 and the hydrogen drying area 5-2. The outlet of the water outlet and drain valve 5-7 is connected to the drain port 5-9, and the outlet of the hydrogen drying area 5-2 is connected to the exhaust hydrogen storage bottle 5-4 through the hydrogen bottle mouth solenoid valve 5-8.
[0035] In the air supply module 3, the outlet of the air compressor 3-1 is connected to the purge pipe 6-3, and the purge pipe 6-3 is connected to the hydrogen drying area 5-2 and the exhaust water separation area 5-3 in the shell 5-1 through the purge solenoid valve 1 6-1. The shell 5-1 is also connected to the purge outlet 6-4 through the purge solenoid valve 2 6-2. Fig.11 As shown, during purging, excess water in the hydrogen dryer 5-2 and the exhaust water separation area 5-3 is discharged.
[0036] A frame 5-12 is provided in the outer shell 5-1, and a support body 5-15 is provided in the frame. The upper part of the support body 5-15 is a hydrogen drying area 5-2, and the lower part of the support body 5-15 is an exhaust water separation area 5-3. The support body 5-15 includes several layers of support plates 5-18 connected in a serpentine shape, and a gas passage hole 5-19 is provided on the surface of the support plate 5-18 at the serpentine turning point.
[0037] The side end surface of the support plate 5-18 abuts against the inner wall of the frame 5-12 to ensure that the gas flows along the support plate 5-18.
[0038] A plurality of drainage baffles 5-20 are arranged in the support body 5-15 of the exhaust water separation area 5-3. The drainage baffles 5-20 are in the shape of a broken line, which has a blocking effect on water and increases the water separation efficiency.
[0039] Baffles 5-21 are provided at both ends of the support body 5-15 in the hydrogen drying area 5-2, a desiccant 5-22 is provided between the two baffles 5-21, and a plurality of gas through holes 5-23 are provided on the baffle 5-21 for circulating gas.
[0040] A liquid level meter 5-10 is provided in the exhaust water separation area 5-3. In order to prevent hydrogen from being discharged along with water, the liquid level meter 5-10 is required to monitor the water height, and after ensuring that there is a certain amount of water, the water outlet valve 5-7 is opened and the water is discharged from the drain port 5-9. Figure 3 As shown, a liquid level min line 5-10-2 and a liquid level max line 5-10-1 are provided on one side of the liquid level gauge 5-10. When the water is below the liquid level min line 5-10-2, the water outlet drain valve 5-7 is closed to prevent hydrogen from being discharged from the drain port 5-9 along the water outlet drain valve 5-7 when the water is insufficient.
[0041] A hydrogen sensor 5-11 is provided in the housing 5-1 to detect whether hydrogen is leaking and to shut down the system if leakage occurs.
[0042] The anode inlet of the stack module 1 is connected to the hydrogen source 7 through the hydrogen supply module 2. The air supply module 3 includes an air compressor 3-1 and a flow meter 3-2. The cathode inlet of the stack module 1 is connected to the air compressor 3-1. The air compressor 3-1 is connected to the air source through an air pipe, and the air pipe is provided with a flow meter 3-2. The hydrogen supply module 2 provides hydrogen to the stack module 1, and the air supply module 3 provides air to the stack module 1. The stack module 1 uses hydrogen and air to convert chemical energy into electrical energy.
[0043] The above-mentioned method of the fuel cell hydrogen recovery system includes the following modes: S1, normal operation mode: During the operation of the fuel cell module 1, hydrogen and water enter the system water separator 4 from the anode outlet, a part of the hydrogen and water vapor enter the hydrogen supply module 2, and the other part of the hydrogen and water vapor pass through the hydrogen inlet pipe 5-5 and the water inlet drain valve 5-6 to reach the exhaust water separation area 5-3. In the exhaust water separation area 5-3, the water vapor is further separated, and the separated hydrogen enters the hydrogen drying area 5-2, and the residual water vapor in the hydrogen is finally dried. The dried hydrogen passes through the hydrogen bottle mouth solenoid valve 5-8 and then enters the exhaust hydrogen storage bottle 5-4. The water separated in the exhaust water separation area 5-3 is discharged through the water outlet drain valve 5-7.
[0044] In mode S1, the water inlet and outlet valves 5-6 and the hydrogen bottle mouth solenoid valve 5-8 are opened to ensure that the hydrogen can be smoothly separated, dried and stored; the purge solenoid valve 1 6-1 and the purge solenoid valve 2 6-2 are both in the closed state to prevent hydrogen from leaking through other channels.
[0045] In mode S1, the mixed gas entering the hydrogen inlet pipe 5-5 first enters the support plate 5-18 of the exhaust water separation zone 5-3, flows along the serpentine support plate 5-18, and enters the support plate 5-18 of the upper layer through the gas through hole 1 5-19 at the turning point of the support plate 5-18. At the same time, under the action of the zigzag drainage baffle 5-20, the flow direction of the mixed gas is a zigzag direction, and finally enters the hydrogen drying zone 5-2 through the gas through hole 1 5-19. The gas from the exhaust water separation zone 5-3 passes through the gas through hole 2 5-23 of the baffle 5-21 on one side, enters the interior of the support body 5-15, passes through the desiccant 5-22, and then passes through the gas through hole 2 5-23 of the baffle on the other side and the gas flow hole 1 5-19 of the support plate 5-18, and enters the upper layer, thereby achieving the purpose of drying hydrogen. Fig.10 As shown, the mixed gas passes through the exhaust water separation area 5-3 and the hydrogen drying area 5-2, and finally enters the exhaust hydrogen storage bottle 5-4 for collection. When the exhaust hydrogen storage bottle 5-4 is full, the cover plate 5-26 of the housing 5-1 is opened to replace the exhaust hydrogen storage bottle 5-4.
[0046] S2, hydrogen dryer regeneration mode: the stack module 1 stops running, and the air compressor of the air supply module 3 continues to run. The compressed dry air passes through the purge pipe 6 and the purge solenoid valve 6-1 and enters the hydrogen drying area 5-2 and the exhaust water separation area 5-3 respectively to purge and dry the moisture. The purged gas is discharged from the purge outlet 5-9 and the drain outlet 6-4.
[0047] In mode S2, the purge solenoid valve 1 6-1, the purge solenoid valve 2 6-2, and the water outlet drain valve 5-7 are opened to ensure gas circulation; the water inlet drain valve 5-6 and the hydrogen bottle mouth solenoid valve 5-8 are closed to prevent the purge gas from entering the exhaust hydrogen storage bottle 5-4 and the system water distributor 4.
[0048] It also includes mode S3, hydrogen leakage detection mode: when the hydrogen concentration sensor 5-11 detects the presence of a certain amount of hydrogen in the hydrogen recovery module 5, the system reduces power or stops running and waits for maintenance personnel to inspect.
[0049] During specific use, the hydrogen bottle replacement time, the size of the hydrogen water separator, and the capacity of the hydrogen dryer are combined with the vehicle maintenance time, and based on the fuel cell system calibration, the amount of hydrogen produced is known, the type of desiccant required and the filling amount are calculated, and the volumes of the three are calculated.
[0050] When used specifically, the hydrogen recovery module 5 of the present invention can be placed at a certain position of the vehicle, or can be integrated into the fuel cell system according to the layout of the fuel cell system.
[0051] The hydrogen source of the present invention is the mixed gas at the anode outlet, that is, a mixture of hydrogen and water vapor, rather than the mixed gas of hydrogen and air discharged from the tail outlet in the actual product. The present invention uses water separation, drying, and hydrogen bottle storage for the mixed gas of the anode water outlet, adds a solenoid valve and a sensor, and adds control logic to process the mixed gas. Considering the regeneration of the desiccant, the control logic is added to dry the desiccant.
Claims
1. A fuel cell hydrogen recovery system, comprising a hydrogen supply module, an air supply module, and a fuel cell stack module, characterized in that: The anode outlet of the stack module (1) is connected to a system water distributor (4), and the outlet of the system water distributor (4) is respectively connected to a hydrogen supply module (2) and a hydrogen recovery module (5). The hydrogen recovery module (5) comprises a housing (5-1), a hydrogen drying area (5-2), an exhaust water distributor area (5-3), and an exhaust hydrogen storage bottle (5-4). The outlet of the system water distributor (4) is connected to a water inlet and drain valve (5-6) through a hydrogen inlet pipe (5-5), and the outlet of the water inlet and drain valve (5-6) is connected to the inlet of the exhaust water distributor area (5-3). The outlet of the exhaust water distributor area (5-3) is divided into two paths and respectively connected to a water outlet and drain valve (5-7) and a hydrogen drying area (5-2). The outlet of the water outlet and drain valve (5-7) is connected to a drain port (5-9), and the outlet of the hydrogen drying area (5-2) is connected to the exhaust hydrogen storage bottle (5-4) through a hydrogen bottle port solenoid valve (5-8).
2. A fuel cell hydrogen recovery system according to claim 1, characterized in that: In the air supply module (3), the outlet of the air compressor (3-1) is connected to the purge pipe (6-3), and the purge pipe (6-3) is connected to the hydrogen drying area (5-2) and the exhaust water separation area (5-3) in the shell (5-1) through the purge solenoid valve 1 (6-1), and the shell (5-1) is also connected to the purge outlet (6-4) through the purge solenoid valve 2 (6-2).
3. A fuel cell hydrogen recovery system according to claim 1, characterized in that: The shell (5-1) is provided with a frame (5-12) inside, and a support body (5-15) is provided inside the frame. The upper part of the support body (5-15) is a hydrogen drying area (5-2), and the lower part of the support body (5-15) is an exhaust water separation area (5-3). The support body (5-15) includes a plurality of layers of support plates (5-18) connected in a serpentine shape, and a gas passage hole (5-19) is provided on the surface of the support plate (5-18) at the serpentine turn.
4. A fuel cell hydrogen recovery system according to claim 3, characterized in that: A plurality of drainage baffles (5-20) are arranged in the support body (5-15) of the exhaust water separation area (5-3), and the drainage baffles (5-20) are in the shape of a broken line.
5. A fuel cell hydrogen recovery system according to claim 3, characterized in that: Baffles (5-21) are provided at both ends of the support body (5-15) in the hydrogen drying zone (5-2), a desiccant (5-22) is provided between the two baffles (5-21), and a plurality of gas passing holes (5-23) are provided on the baffle (5-21).
6. A fuel cell hydrogen recovery system according to claim 1, characterized in that: A liquid level meter (5-10) is provided in the exhaust water separation area (5-3); and a hydrogen sensor (5-11) is provided in the housing (5-1).
7. A method for a fuel cell hydrogen recovery system according to any one of claims 1 to 6, characterized in that: The following modes are included: S1, normal operation mode: during the operation of the stack module (1), hydrogen and water enter the system water separator (4) from the anode outlet, a part of the hydrogen and water vapor enter the hydrogen supply module (2), and the other part of the hydrogen and water vapor passes through the hydrogen inlet pipe (5-5) and the water inlet and drain valve (5-6) to reach the exhaust water separation area (5-3). In the exhaust water separation area (5-3), the water vapor is further separated, and the separated hydrogen enters the hydrogen drying area (5-2) to perform final drying on the residual water vapor in the hydrogen. The dried hydrogen passes through the hydrogen bottle mouth solenoid valve (5-8) and enters the exhaust hydrogen storage bottle (5-4). The water separated in the exhaust water separation area (5-3) is discharged through the water outlet and drain valve (5-7); S2, hydrogen dryer regeneration mode: the stack module (1) stops running, and the air compressor of the air supply module (3) continues to run. The compressed dry air passes through the purge pipe (6) and the purge solenoid valve 1 (6-1) and enters the hydrogen drying area (5-2) and the exhaust water separation area (5-3) respectively to purge and dry the moisture. The purged gas is discharged from the purge outlet (5-9) and the drain outlet (6-4).
8. The method of a fuel cell hydrogen recovery system according to claim 7, characterized in that: In the mode S1, the water inlet and outlet valve (5-6) and the hydrogen bottle mouth solenoid valve (5-8) are opened to ensure that hydrogen can be smoothly separated, dried and stored; the purge solenoid valve 1 (6-1) and the purge solenoid valve 2 (6-2) are both in a closed state to prevent hydrogen from leaking through other channels.
9. The method of a fuel cell hydrogen recovery system according to claim 7, characterized in that: In the mode S2, the purge solenoid valve 1 (6-1), the purge solenoid valve 2 (6-2), and the water outlet drain valve (5-7) are opened to ensure gas circulation; the water inlet drain valve (5-6) and the hydrogen bottle mouth solenoid valve (5-8) are closed to prevent the purge gas from entering the exhaust hydrogen storage bottle (5-4) and the system water distributor (4).
10. The method of a fuel cell hydrogen recovery system according to claim 7, characterized in that: The system also includes mode S3, a hydrogen leakage detection mode: when the hydrogen concentration sensor (5-11) detects that a certain amount of hydrogen exists in the hydrogen recovery module (5), the system reduces power or stops running, waiting for maintenance personnel to inspect and repair.