Liquid hydrogen filling system and hydrogen refueling station

Abstract

The utility model provides a liquid hydrogen filling system and a hydrogen refueling station. The liquid hydrogen filling system comprises a plunger pump, a check valve, a filling pipe and a diffusing assembly. Wherein the plunger pump is communicated with the storage tank, the filling pipe is communicated with the downstream of the plunger pump, the filling pipe is communicated between the plunger pump and the check valve, and the diffusing assembly is communicated with the filling pipe and used for releasing pressure in the filling pipe. Specifically, the bleeding assembly comprises a detector, a bleeding valve and a controller, the detector and the bleeding valve communicate with the filling pipe, and the controller is electrically connected with the detector and the bleeding valve, so that the controller can control the bleeding valve to be selectively opened or closed through a detection signal fed back by the detector, and the pipeline pressure in the filling pipe is released; therefore, the pressure of the plunger pump is reduced, and the working safety of the plunger pump is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of hydrogen energy application, in particular to a liquid hydrogen filling system and a hydrogen filling station. Background Art

[0002] During the liquid hydrogen filling process, a plunger pump is required to drive the liquid hydrogen flow to complete the filling work. After a running cycle of the liquid hydrogen plunger pump, a high-pressure closed system is formed in the pipeline behind the pump, and the liquid hydrogen is gasified due to heat leakage in the pipeline, resulting in high pressure in the pipeline behind the pump. When the plunger pump is started next time, the back pressure is too high, which will affect the safety of the plunger pump. The existing practice is to set a manual relief valve on the outlet pipeline of the plunger pump for manual discharge to reduce the back pressure of the plunger pump.

[0003] However, in hydrogen refueling stations where liquid hydrogen needs to be frequently refueled, the plunger pump of the refueling system needs to be started and stopped multiple times, and manual operation of the release valve is prone to operating errors, causing excessive release of liquid hydrogen in the pipeline, resulting in the plunger pump losing positive pressure and destroying the high-purity hydrogen environment inside the pipeline, causing the pipeline to be blocked by ice or causing the risk of hydrogen-oxygen mixture explosion. Utility Model Content

[0004] The utility model aims to provide a liquid hydrogen filling system which can automatically reduce the back pressure of a plunger pump.

[0005] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0006] A liquid hydrogen filling system is connected to a storage tank storing liquid hydrogen, and the liquid hydrogen filling system includes: a plunger pump connected to the storage tank to drive the liquid hydrogen to flow out of the storage tank; a check valve connected to the downstream of the plunger pump to prevent the liquid hydrogen downstream of the check valve from flowing back; a filling pipe connected between the plunger pump and the check valve; and a relief assembly, which includes a detector, a relief valve, and a controller; the detector is connected to the filling pipe to detect the pressure in the filling pipe; the relief valve is connected to the filling pipe to release the pressure in the filling pipe; the controller is electrically connected to the detector and the relief valve to selectively control the opening or closing of the relief valve.

[0007] In one embodiment of the present application, the liquid hydrogen filling system further includes a vaporizer; the vaporizer is connected downstream of the check valve to convert the liquid hydrogen into hydrogen gas.

[0008] In one embodiment of the present application, the liquid hydrogen filling system further includes a safety valve; the safety valve is connected between the check valve and the vaporizer so as to selectively release the pressure in the pipeline between the check valve and the vaporizer.

[0009] In one embodiment of the present application, the liquid hydrogen filling system also includes a liquid outlet pipeline and an air return pipeline; one end of the liquid outlet pipeline is connected to the bottom of the storage tank, and the other end is connected to the plunger pump; one end of the air return pipeline is connected to the top of the storage tank, and the other end is connected to the plunger pump to balance the pressure in the storage tank.

[0010] In one embodiment of the present application, the liquid outlet pipeline and the air return pipeline are provided with a vacuum insulation layer to thermally insulate the liquid outlet pipeline and the air return pipeline.

[0011] In one embodiment of the present application, the plunger pump includes a pump body and a motor; the motor is used to drive the pump body; the motor is electrically connected to the controller so that the motor works or stops under the control of the controller.

[0012] In one embodiment of the present application, the detector is a pressure transmitter.

[0013] In one embodiment of the present application, the relief valve is a solenoid valve.

[0014] In one embodiment of the present application, the vaporizer is an air-temperature vaporizer.

[0015] The present application also discloses a hydrogen refueling station, which includes a liquid hydrogen storage tank for storing liquid hydrogen, and any of the liquid hydrogen filling systems described above; the liquid hydrogen filling system is connected to the liquid hydrogen storage tank so as to be able to fill the liquid hydrogen externally.

[0016] It can be seen from the above technical solution that the utility model has at least the following advantages and positive effects:

[0017] In the utility model, the liquid hydrogen filling system includes a plunger pump, a check valve, a filling pipe and a relief component. Among them, the plunger pump is connected to the storage tank, the filling pipe is connected to the downstream of the plunger pump, the filling pipe is connected between the plunger pump and the check valve, and the relief component is connected to the filling pipe to release the pressure in the filling pipe. Specifically, the relief component includes a detector, a relief valve and a controller, and the detector and the relief valve are connected to the filling pipe. The controller electrically connects the detector and the relief valve, so that the controller can control the relief valve to selectively open or close through the detection signal fed back by the detector, thereby releasing the pipeline pressure in the filling pipe, thereby reducing the pressure of the plunger pump and ensuring the working safety of the plunger pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of a liquid hydrogen filling system according to an embodiment of the utility model.

[0019] The following are the descriptions of the reference numerals:

[0020] 1-storage tank; 2-liquid outlet pipeline; 3-air return pipeline; 4-vacuum insulation layer; 10-piston pump; 11-pump body; 12-motor; 20-check valve; 30-filling pipe; 31-connecting pipe; 40-release assembly; 41-detector; 42-release valve; 43-controller; 50-vaporizer; 60-safety valve. DETAILED DESCRIPTION

[0021] Typical embodiments that embody the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various changes in different embodiments without departing from the scope of the present invention, and the descriptions and illustrations therein are essentially for illustrative purposes rather than for limiting the present invention.

[0022] In the description of the present invention, it should be understood that in the embodiments shown in the drawings, the indications of directions or positional relationships (such as up, down, left, right, front and back, etc.) are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation. These descriptions are appropriate when these elements are in the positions shown in the drawings. If the descriptions of the positions of these elements change, the indications of these directions also change accordingly.

[0023] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0024] In actual use, after a liquid hydrogen cryogenic plunger pump completes an operating cycle, a high-pressure closed system will be formed in the pipeline behind the plunger pump. And due to factors such as heat leakage in the pipeline, the liquid hydrogen is gasified, making the pressure in the pipeline very high, causing the plunger pump to start the pump next time. The back pressure is too high, resulting in poor liquid discharge, which in turn makes it difficult for the pump to start pressure and is prone to failure due to idling. At the same time, when the back pressure of the plunger pump is too low, the plunger pump will lose positive pressure and destroy the high-purity hydrogen environment inside the pipeline, causing ice blockage in the pipeline or the risk of hydrogen-oxygen mixture explosion. That is, the back pressure of the plunger pump is too high or too low, which will affect the normal use of the plunger pump and pipeline. In addition, in hydrogen refueling stations where liquid hydrogen is often needed, the plunger pump in the filling system needs to be started and stopped many times during actual use.

[0025] However, the existing control method is to manually release the hydrogen pressure in the pipeline downstream of the plunger pump, which makes the release valve easy to operate incorrectly, causing the pressure in the liquid hydrogen pipeline to be released excessively or insufficiently, thereby affecting the safe operation of the plunger pump. Therefore, a liquid hydrogen filling system is proposed to solve the above problem.

[0026] The scheme is further illustrated by the following examples:

[0027] It should be noted that, in this embodiment, a hydrogen refueling station is also provided, which is used to fill hydrogen externally, such as filling hydrogen into a fuel vehicle or filling hydrogen into a hydrogen storage tank, etc. Specifically, the hydrogen refueling station includes a liquid hydrogen storage tank for storing liquid hydrogen and a liquid hydrogen filling system for filling liquid hydrogen, and the liquid hydrogen filling system is connected to the liquid hydrogen storage tank so that liquid hydrogen can be filled externally.

[0028] See also Figure 1 The liquid hydrogen filling system of this embodiment includes a plunger pump 10, a check valve 20, a filling pipe 30 and a release component 40. The plunger pump 10 is connected to a storage tank 1 storing liquid hydrogen to drive the liquid hydrogen to flow out of the storage tank 1. The check valve 20 is connected downstream of the plunger pump 10 to prevent the liquid hydrogen downstream of the check valve 20 from flowing back. The filling pipe 30 is connected between the plunger pump 10 and the check valve 20, that is, the plunger pump 10 and the check valve 20 are connected through the filling pipe 30. The release component 40 is connected to the filling pipe 30 so as to be able to release the pressure in the filling pipe 30, that is, the release component 40 is used to release the back pressure of the plunger pump 10.

[0029] Specifically, in this embodiment, the relief component 40 includes a detector 41, a relief valve 42 and a controller 43. The detector 41 is connected to the filling pipe 30 to detect the pressure in the filling pipe 30 and generate a detection signal. The relief valve 42 is connected to the filling pipe 30 to release the pressure in the filling pipe 30. The controller 43 is electrically connected to the detector 41 and the relief valve 42, so that the controller 43 can selectively control the opening or closing of the relief valve 42 through the detection signal generated by the detector 41, that is, when the detector 41 detects that the pressure in the filling pipe 30 is greater than a preset value, the controller 43 controls the relief valve 42 to open, thereby releasing the pressure in the filling pipe 30, thereby reducing the back pressure of the plunger pump 10, so that the back pressure of the plunger pump 10 is between a suitable pressure value, thereby ensuring that the plunger pump 10 can be opened smoothly.

[0030] It should be noted that when the detector 41 detects that the pressure in the filling pipe 30 is greater than the preset value, the controller 43 controls the relief valve 42 to open to release the pressure in the filling pipe 30 and reduce the pressure in the filling pipe 30. When the detector 41 detects that the pressure in the filling pipe 30 is equal to the preset pressure value, the controller 43 controls the relief valve 42 to close to prevent the relief valve 42 from excessively releasing and causing the pressure in the filling pipe 30 to be lower than the preset value, thereby causing the back pressure of the plunger pump 10 to be too low and affecting the positive pressure of the plunger pump 10. At the same time, it prevents the pressure in the filling pipe 30 from being too low, causing air to enter the filling pipe 30, so that the air affects the high-purity hydrogen environment in the filling pipe 30 and affects the pipeline safety in the filling pipe 30.

[0031] See also Figure 1 In this embodiment, the plunger pump 10 includes a pump body 11 and a motor 12. Specifically, the motor 12 is used to drive the pump body 11 to work. In addition, the motor 12 is electrically connected to the controller 43, so that the motor 12 works or stops under the control of the controller 43 to drive the liquid hydrogen in the storage tank 1 to flow.

[0032] In addition, in the present embodiment, the detector 41 is a pressure transmitter, which converts the pressure value detected in the filling pipe 30 into an electrical signal and transmits it to the controller 43. In addition, the relief valve 42 is a solenoid valve, so that the controller 43 can directly control the opening or closing of the relief valve 42 through an electrical signal. The controller 43 is a PLC control module, which controls the opening or closing of the relief valve 42 through the electrical signal fed back by the detector 41.

[0033] See also Figure 1 The liquid hydrogen filling system further includes a vaporizer 50. The vaporizer 50 is connected to the downstream of the check valve 20 to convert liquid hydrogen into hydrogen gas, so as to facilitate the external filling of liquid hydrogen. Specifically, in this embodiment, the check valve 20 and the vaporizer 50 are connected by a connecting pipe 31 to guide the liquid hydrogen to flow to the vaporizer 50.

[0034] It should be noted that, in this embodiment, the vaporizer 50 is an air-temperature vaporizer 50 to complete the gasification of liquid hydrogen.

[0035] See also Figure 1 The liquid hydrogen filling system also includes a safety valve 60. The safety valve 60 is connected between the check valve 20 and the vaporizer 50 to selectively release the pressure in the pipeline between the check valve 20 and the vaporizer 50. That is, the safety valve 60 is connected to the connecting pipe 31 to release the pipeline pressure in the connecting pipe 31 to prevent the pressure in the filling pipe 30 from being too high. When the relief assembly 40 cannot release the pressure in the pipeline in time, the safety valve 60 can be opened to ensure the safety of the pipelines in the filling pipe 30 and the connecting pipe 31, and to ensure that the back pressure of the plunger pump 10 is within a safe range.

[0036] See also Figure 1 The liquid hydrogen filling system also includes a liquid outlet pipeline 2 and a gas return pipeline 3. One end of the liquid outlet pipeline 2 is connected to the bottom of the storage tank 1, and the other end is connected to the plunger pump 10, so as to guide the liquid hydrogen to flow out of the storage tank 1 and fill the liquid hydrogen out under the drive of the plunger pump 10. In addition, one end of the gas return pipeline 3 is connected to the top of the storage tank 1, and the other end is connected to the plunger pump 10 to balance the pressure in the storage tank 1 and facilitate the liquid hydrogen to flow out of the storage tank 1.

[0037] It should be noted that, in the present embodiment, the liquid outlet pipeline 2 and the gas return pipeline 3 are provided with a vacuum insulation layer 4 to thermally insulate the liquid outlet pipeline 2 and the gas return pipeline 3 to prevent the ambient temperature from affecting the liquid hydrogen in the liquid outlet pipeline 2 or the hydrogen in the gas return pipeline 3.

[0038] Of course, in some other embodiments, the vacuum insulation layer 4 can also be set as other thermal insulation layers, such as wrapped with insulation materials to insulate the liquid outlet pipeline 2 and the return air pipeline 3 to form insulation inside the liquid outlet pipeline 2 and the return air pipeline 3.

[0039] In summary, the filling pipe 30 is connected to the downstream of the plunger pump 10 and is located upstream of the check valve 20, and the relief component 40 is connected to the filling pipe 30, that is, the detector 41 and the relief valve 42 are both connected to the filling pipe 30, and the controller 43 is electrically connected to the detector 41 and the relief valve 42, so that the pressure in the filling pipe 30 can be automatically released to ensure that the pressure in the filling pipe 30 is within a preset range, and the back pressure of the plunger pump 10 is within a preset range, that is, the normal startup of the plunger pump 10 can be guaranteed, and the high-purity hydrogen environment in the filling pipe 30 can be guaranteed, and the safety of the use of the liquid hydrogen filling system can be ensured.

[0040] Although the utility model has been described with reference to several typical embodiments, it should be understood that the terms used are illustrative and exemplary, rather than restrictive. Since the utility model can be implemented in a variety of forms without departing from the spirit or essence of the utility model, it should be understood that the above-mentioned embodiments are not limited to any of the aforementioned details, but should be widely interpreted within the spirit and scope defined by the attached claims, so all changes and modifications falling within the scope of the claims or their equivalents should be covered by the attached claims.

Claims

1. A liquid hydrogen filling system connected to a storage tank storing liquid hydrogen, characterized in that: The liquid hydrogen filling system comprises: a plunger pump connected to the storage tank to drive the liquid hydrogen to flow out of the storage tank; a check valve connected to the downstream of the plunger pump to prevent the backflow of liquid hydrogen downstream of the check valve; a filling pipe connected between the plunger pump and the check valve; and A relief assembly includes a detector, a relief valve, and a controller; the detector is connected to the filling pipe to detect the pressure in the filling pipe; the relief valve is connected to the filling pipe to release the pressure in the filling pipe; the controller is electrically connected to the detector and the relief valve to selectively control the opening or closing of the relief valve.

2. The liquid hydrogen filling system according to claim 1, characterized in that: A vaporizer is also included; the vaporizer is connected downstream of the check valve to convert the liquid hydrogen into hydrogen gas.

3. The liquid hydrogen filling system according to claim 2, characterized in that: It also includes a safety valve; the safety valve is connected between the check valve and the vaporizer to selectively release the pressure in the pipeline between the check valve and the vaporizer.

4. The liquid hydrogen filling system according to claim 1, characterized in that: It also includes a liquid outlet pipeline and an air return pipeline; one end of the liquid outlet pipeline is connected to the bottom of the storage tank, and the other end is connected to the plunger pump; one end of the air return pipeline is connected to the top of the storage tank, and the other end is connected to the plunger pump to balance the pressure in the storage tank.

5. The liquid hydrogen filling system according to claim 4, characterized in that: The liquid outlet pipeline and the air return pipeline are provided with a vacuum insulation layer to thermally insulate the liquid outlet pipeline and the air return pipeline.

6. The liquid hydrogen filling system according to claim 1, characterized in that: The plunger pump comprises a pump body and a motor; the motor is used to drive the pump body; the motor is electrically connected to the controller so that the motor works or stops under the control of the controller.

7. The liquid hydrogen filling system according to claim 1, characterized in that: The detector is a pressure transmitter.

8. The liquid hydrogen filling system according to claim 1, characterized in that: The relief valve is a solenoid valve.

9. The liquid hydrogen filling system according to claim 2, characterized in that: The vaporizer is an air-temperature vaporizer.

10. A hydrogen refueling station, characterized in that: The hydrogen refueling station includes a liquid hydrogen storage tank for storing liquid hydrogen, and a liquid hydrogen filling system according to any one of claims 1 to 9; the liquid hydrogen filling system is connected to the liquid hydrogen storage tank so as to be able to fill the liquid hydrogen externally.

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