Pre-cooling system for hydrogen refueling station

Abstract

The invention provides a pre-cooling system for a hydrogen refueling station, which comprises a first injection unit which comprises a hydrogen storage bottle arranged in the hydrogen refueling station and a first conveying channel arranged at the outlet end of the hydrogen storage bottle, and a heat exchange unit which is arranged on the first conveying channel and used for reducing the temperature of hydrogen and comprises a second heat exchange mechanism, the first heat exchange mechanism is arranged between the hydrogen storage bottle and the second heat exchange mechanism, the first heat exchange mechanism comprises a first heat exchanger, and the second heat exchange mechanism comprises a second heat exchanger and a core assembly arranged in the second heat exchanger. The microchannels are arranged in the core body assembly and are used for guiding fluid. According to the pre-cooling system for the hydrogen refueling station, through the two stages of pre-cooling systems, the temperature of output hydrogen can be adaptively adjusted to meet the requirements of different refueling temperatures of a passenger vehicle so as to achieve the purpose of saving energy consumption, and then the safety and stability of the pre-cooling system for the hydrogen refueling station are ensured.

Description

Technical Field

[0001] The invention relates to the field of hydrogenation equipment for high-pressure hydrogenation stations, and in particular to a precooling system for hydrogenation stations. Background Art

[0002] At present, the heat exchangers of the existing hydrogen refueling station precooling system generally use coil heat exchangers or shell-and-tube heat exchangers. Coil heat exchangers can only adapt to the working conditions of 35MPa hydrogen refueling stations. With the development of technology, hydrogen refueling stations with 70MPa refueling capacity are conducive to improving the endurance and economy of hydrogen vehicles, and are gradually becoming mainstream.

[0003] In the range of hydrogen working conditions at hydrogen refueling stations, the Joule-Thomson coefficient μJ-T of hydrogen is negative. According to the Joule-Thomson effect, the temperature of high-pressure hydrogen increases after passing through the throttling element during the operation of the hydrogen refueling station. During the hydrogenation process of fuel cell vehicles, since there are many pressure reducing elements between the gas source of the hydrogen refueling station and the on-board gas cylinder, if effective control measures are not adopted, the temperature in the on-board hydrogen storage bottle will rise sharply. For example, excessively high temperature will threaten the safety of hydrogen storage tanks and on-board gas cylinders at hydrogen refueling stations. In the worst case, the hydrogen storage density in the gas cylinder is too low and the hydrogen storage capacity is low; in the worst case, the hydrogen storage bottle fails and hydrogen leaks. Therefore, hydrogen refueling stations using coil heat exchangers will be difficult to meet the demand. Since the shell-and-tube heat exchanger has the disadvantages of large flow resistance and large footprint, it will be difficult to control the flow of hydrogen if only the shell-and-tube heat exchanger is used for traditional precooling in a 70MPa hydrogen refueling station, which will easily cause serious safety hazards and it will also be difficult to meet the requirements of high-pressure working conditions for hydrogen transportation.

[0004] CN208779984U discloses a heat exchanger for a hydrogen refueling station, including a plurality of U-shaped tubes arranged vertically and having a sleeve structure, a high-pressure tube arranged therein, a cooling channel formed between the high-pressure tube and the U-shaped tube, a flexible connecting tube and a high-pressure connecting tube arranged on one side of the adjacent U-shaped tube, the flexible connecting tube connects the cooling channels on one side of the adjacent U-shaped tube, and a plurality of U-shaped tubes are connected by the flexible connecting tube to form a continuous cooling channel, one end of the cooling channel is a cooling water inlet, and the other end is a cooling water outlet, the high-pressure connecting tube connects the high-pressure tubes on one side of the adjacent U-shaped tube, and a plurality of U-shaped tubes are connected by the high-pressure connecting tube to form a continuous high-pressure hydrogen channel, one end of the high-pressure hydrogen channel is a hydrogen inlet, and the other end is a hydrogen outlet. Although the device can cool high-pressure hydrogen, it still cannot meet the requirements of passenger cars for different filling temperatures.

[0005] Therefore, it is desirable in the art to provide a precooling system for a hydrogen refueling station to solve the above technical problems. Summary of the invention

[0006] The purpose of the present invention is to propose a precooling system for a hydrogen refueling station, which is equipped with a two-stage precooling system, and realizes primary precooling through a first heat exchanger and secondary precooling through a second heat exchanger, so that the high-pressure hydrogen whose temperature rises suddenly after passing through the hydrogen compressor can be cooled and reduced in stages to meet the requirements of passenger cars for different refueling temperatures.

[0007] According to the present invention, a precooling system for a hydrogen refueling station is provided, comprising a first injection unit, which comprises a hydrogen storage bottle arranged in the hydrogen refueling station, and a first delivery channel arranged at the outlet end of the hydrogen storage bottle,

[0008] A heat exchange unit disposed on the first delivery channel and used to reduce the temperature of the hydrogen includes a second heat exchange mechanism and a first heat exchange mechanism disposed between the hydrogen storage bottle and the second heat exchange mechanism.

[0009] The first heat exchange mechanism includes a first heat exchanger, and the second heat exchange mechanism includes a second heat exchanger, a core assembly arranged in the second heat exchanger, and a plurality of microchannels arranged in the core assembly and used for guiding fluid.

[0010] In one embodiment, the second heat exchanger is a microchannel heat exchanger, and a plurality of the core assemblies which are sealed and connected are arranged in the microchannel heat exchanger in a transverse direction.

[0011] In one embodiment, the core assembly includes a plurality of flow channel plates arranged vertically and sealed to each other, and the microchannels are photochemically etched in the flow channel plates.

[0012] In one embodiment, the microchannel is configured as any one of circular, square and triangular hole structures.

[0013] In one embodiment, the microchannel includes a first channel portion configured in a straight line and arranged in a transverse direction for guiding the hydrogen, and a second channel portion configured in a curved line and arranged in a longitudinal direction for guiding a cooling medium.

[0014] In one embodiment, the flow channel plate includes a first flow portion, the first flow portion includes a first connecting portion and a second connecting portion that are symmetrically arranged, the first connecting portion and the second connecting portion are connected together to form a connecting body, and a plurality of spaced-apart first channel portions are arranged in the connecting body.

[0015] In one embodiment, the flow channel plate further includes a second flow portion, the second flow portion is constructed as an integrally formed structure, and a plurality of spaced-apart second channel portions are arranged in the second flow portion.

[0016] In one embodiment, the first flow portions and the second flow portions are alternately arranged in the vertical direction.

[0017] In one embodiment, the first heat exchange mechanism comprises a first sensor disposed between the second heat exchanger and the first heat exchanger for monitoring the temperature of the hydrogen, wherein the first heat exchanger is configured as a double-tube heat exchanger.

[0018] In one embodiment, the first injection unit further includes a hydrogen compressor disposed between the hydrogen storage bottle and the first heat exchanger, a stop valve disposed at an inlet end of the hydrogen compressor, and a safety valve disposed on the hydrogen storage bottle.

[0019] In one embodiment, at least two second delivery channels arranged in parallel are formed at the outlet end of the first heat exchanger, and the second heat exchange mechanism is disposed on the second delivery channels.

[0020] In one embodiment, the second heat exchange mechanism further includes a check valve and a flow control valve sequentially disposed at the inlet end of the second heat exchanger.

[0021] In one embodiment, the precooling system further includes a second injection unit, the second injection unit including a hydrogenation hose disposed between the passenger car and the second heat exchanger, and a second sensor disposed on the hydrogenation hose and used to record a hydrogen flow rate.

[0022] Compared with the prior art, the advantages of the present invention are:

[0023] First, the present invention sets up a two-stage precooling system in the entire hydrogenation line, and realizes primary precooling through the first heat exchanger and secondary precooling through the second heat exchanger, so that the high-pressure hydrogen whose temperature rises suddenly after passing through the hydrogen compressor can be cooled and lowered in stages to meet the requirements of passenger cars for different filling temperatures.

[0024] Compared with a hydrogen refueling station with a filling capacity of 35MPa, a hydrogen refueling station with a filling capacity of 70MPa can effectively increase the one-time hydrogen filling amount and filling time for passenger cars, thereby improving the endurance and economy of passenger cars (such as hydrogen energy vehicles). Although the shell-and-tube heat exchanger in the prior art can withstand the high-pressure working condition of 70MPa, if only the shell-and-tube heat exchanger is used as the pre-cooling body of the 70MPa hydrogen refueling station, the volume of the shell-and-tube heat exchanger will be larger. In addition, since the hydrogen delivery volume per unit time has been doubled from the 35MPa hydrogen refueling station to the 70MPa hydrogen refueling station, it will be difficult to accurately control the high-pressure hydrogen flow rate only through the shell-and-tube heat exchanger.

[0025] Compared with the prior art, the present application adopts a two-stage precooling system consisting of a second heat exchanger and a first heat exchanger, so that the high-pressure hydrogen in the first delivery channel and the second delivery channel can be maintained at a controllable temperature, thereby ensuring the safety and stability of the precooling system used in the hydrogen refueling station.

[0026] Compared with the traditional single-stage precooling system, the present invention can adaptively adjust the temperature of the output hydrogen through the first heat exchanger and the second heat exchanger, so as to meet the refueling requirements of different passenger cars. Moreover, since it can meet the refueling temperatures of different passenger cars, it effectively reduces and saves the energy consumption of the precooling system used in the hydrogen refueling station.

[0027] Secondly, the high-pressure hydrogen of the present application can be split after the primary precooling of the first heat exchanger, thereby flowing to the second heat exchanger on the multiple second delivery channels for secondary precooling.

[0028] Specifically, the hydrogen after primary precooling in the first heat exchanger can be diverted in the first delivery channel, and the diverted hydrogen flows into the second heat exchanger through the second delivery channel respectively, and this part of the hydrogen can be transported to different passenger cars 6 after secondary precooling in the second heat exchanger to achieve rapid hydrogen refueling.

[0029] In this way, the purpose of simultaneously refueling multiple passenger cars can be achieved under the diversion effect of the second delivery channel. The high-pressure hydrogen output can not only meet the requirements of the refueling time and refueling amount of the passenger cars, but also the high-pressure hydrogen output under the action of the second heat exchanger can also have good stability.

[0030] Thirdly, the present application can provide independent channels for high-pressure hydrogen and cooling medium through the microchannels on the flow channel plate, thereby ensuring that the high-pressure hydrogen delivered to the passenger car can meet the temperature requirements of hydrogen filling, further improving the stability of the precooling system used in the hydrogen filling station.

[0031] Accordingly, since adjacent core components are sealed and connected, and hydrogen has an independent transport channel, it is ensured that hydrogen can be safely precooled in the second heat exchange mechanism, thereby improving the accuracy and sensitivity of the precooling system for the hydrogen refueling station to control the hydrogen flow rate, and further improving the success rate of hydrogen refueling.

[0032] In addition, since the pore size of the microchannel is small (generally 2 mm), hydrogen or cooling medium can fill the entire microchannel, thereby effectively reducing the flow resistance of hydrogen or cooling medium in the second heat exchanger, and further improving the heat exchange efficiency of the second heat exchanger, so that the second heat exchanger can have a good cooling effect on the high-pressure gas in the hydrogen refueling station.

[0033] In addition, the present invention can smoothly complete the task of refueling 5kg of hydrogen for a passenger car in 3 to 5 minutes under the staged cooling effect of the second heat exchanger and the first heat exchanger. Moreover, the present invention also has the ability to operate safely in a high-pressure hydrogen environment, thereby improving the safety and reliability of the precooling system used in the hydrogen refueling station.

[0034] Fourthly, the present invention can be adapted to hydrogen refueling stations under different pressures, such as 35MPa hydrogen refueling stations and 70MPa hydrogen refueling stations. Moreover, the present invention can also adjust the temperature of the output hydrogen according to the actual working condition of the remaining hydrogen in the passenger car and through the secondary precooling of the first heat exchanger and the second heat exchanger, so that the output hydrogen meets the refueling requirements of the passenger car.

[0035] In addition, the first heat exchanger of the present invention can control the temperature of hydrogen within the range of -10°C to 100°C, and the second heat exchanger of the present invention can control the temperature of hydrogen within the range of -60°C to -10°C. Therefore, the present invention can achieve phased regulation of the temperature of hydrogen through the first heat exchanger and the second heat exchanger, so that the temperature of hydrogen can be more easily reduced in a short time to meet the filling requirements of the actual working conditions of passenger cars, so as to achieve the purpose of reducing and saving the energy consumption of the precooling system of the hydrogen filling station.

[0036] Fifth, the present application can achieve precise control of the flow rate of high-pressure hydrogen through the microchannel of the second heat exchanger and the flow control valve arranged at the inlet of the second heat exchanger, so as to achieve the purpose of flexibly adjusting the flow rate of high-pressure hydrogen, so that the output high-pressure hydrogen can meet the requirements of rapid refueling of passenger cars.

[0037] Sixth, since the volume of the second heat exchanger is smaller than that of the first heat exchanger, the use of the second heat exchanger can greatly reduce the site occupation and can improve the heat exchange efficiency and precooling effect of the precooling system used in the hydrogen refueling station.

[0038] Seventh, the flow plate is made of 316L stainless steel. The flow plate has good hydrogen embrittlement resistance, which effectively prevents safety problems caused by hydrogen overflow, and the flow plate also has good pressure resistance, so it can fully withstand the pressure brought by high-pressure hydrogen to meet the different high-pressure gas transportation requirements in the hydrogen refueling station.

[0039] In addition, since the second heat exchanger is an integrated structure formed by high temperature (1000℃~1100℃) diffusion welding, the second heat exchanger can be used for precooling of the hydrogen refueling station. Moreover, the second heat exchanger has the advantages of reliable structure, high heat exchange efficiency, small footprint and low leakage, so the second heat exchanger can operate safely in a high-pressure hydrogen environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The present invention will be described in detail below in conjunction with the accompanying drawings, in which:

[0041] Figure 1 The structure of the precooling system for a hydrogen refueling station according to the present invention is schematically shown;

[0042] Figure 2 is a partial schematic diagram of a precooling system for a hydrogen refueling station according to the present invention, which shows the connection relationship between the first circulation part and the second circulation part;

[0043] Figure 3 It is an exploded view of a first flow portion in a precooling system for a hydrogen refueling station according to the present invention.

[0044] In the drawings, the same reference numerals are used for the same components. The drawings are not drawn to scale.

[0045] The meanings of the reference numerals in the accompanying drawings are as follows:

[0046] 11 hydrogen storage bottle, 12 first delivery channel, 13 hydrogen compressor, 14 stop valve, 15 safety valve,

[0047] 2 second heat exchange mechanism, 21 second heat exchanger, 22 core assembly,

[0048] 23 microchannel, 231 first channel portion, 232 second channel portion,

[0049] 24 first flow portion, 241 first connection portion, 242 second connection portion,

[0050] 25 second flow part, 26 check valve, 27 flow control valve,

[0051] 3 first heat exchange mechanism, 31 first heat exchanger, 32 first sensor,

[0052] 4The second conveying channel,

[0053] 51 hydrogenation hose, 52 second sensor,

[0054] 6 Passenger cars. DETAILED DESCRIPTION

[0055] In order to make the technical solutions and advantages of the present invention more clearly understood, the exemplary embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than an exhaustive list of all the embodiments. In addition, the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0056] In the description of the present invention, it should be understood that 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.

[0057] In the present invention, unless otherwise clearly stipulated and limited, terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal connection of two elements.

[0058] For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0059] The present invention will be further described below in conjunction with the accompanying drawings.

[0060] Figure 1 The structure of a precooling system 100 for a hydrogen refueling station according to the present invention is schematically shown;

[0061] Figure 2 is a partial schematic diagram of a precooling system 100 for a hydrogen refueling station according to the present invention, which shows the connection relationship between the first circulation part 24 and the second circulation part 25;

[0062] Figure 3 FIG. 2 is an exploded view of the first flow portion 24 in the precooling system 100 for a hydrogen refueling station according to the present invention.

[0063] like Figure 1 As shown, the precooling system 100 for a hydrogen refueling station according to the present invention includes a first injection unit. The first injection unit includes a hydrogen storage bottle 11 and a first delivery channel 12 arranged in the hydrogen refueling station. Preferably, the first delivery channel 12 is arranged at the outlet end of the hydrogen storage bottle 11, and the hydrogen storage bottle 11 delivers hydrogen through the first delivery channel 12.

[0064] According to the present invention, the precooling system 100 for the hydrogen refueling station further comprises a heat exchange unit. Preferably, the heat exchange unit is arranged on the first delivery channel 12, so as to effectively reduce the temperature of hydrogen during the delivery process, thereby providing effective safety protection for the hydrogen refueling station.

[0065] In one embodiment, Figure 1As shown, the heat exchange unit includes a second heat exchange mechanism 2. The second heat exchange mechanism 2 is installed on the second delivery channel 4 (described below) and includes a second heat exchanger 21. Preferably, the second heat exchanger 22 in the present invention is a microchannel heat exchanger, so that the temperature of the hydrogen in the second delivery channel 4 can be effectively controlled to ensure that the hydrogen can be smoothly delivered from the hydrogen storage bottle 11 to the passenger car 6.

[0066] In one embodiment, Figure 1 As shown, the second heat exchange mechanism 2 further includes a core assembly 22. The core assembly 22 is arranged inside the second heat exchanger 21, so as to allow hydrogen and cooling medium to pass through respectively.

[0067] In a preferred embodiment, Figure 1 As shown, a plurality of core assemblies 22 are arranged in the transverse direction inside the second heat exchanger 21. Adjacent core assemblies 22 are sealedly connected, so as to ensure that the hydrogen passes smoothly through the second heat exchanger 21 and is effectively cooled, so as to ensure the output of the hydrogen in the second delivery channel 4.

[0068] In one embodiment, Figure 1 and 2 As shown, the second heat exchange mechanism 2 further includes a microchannel 23. Preferably, the microchannel 23 is disposed in the core assembly 22, and can provide different channels for hydrogen and cooling medium respectively, so as to ensure that the two can have independent circulation spaces in the second delivery channel 4.

[0069] Furthermore, since the hydrogen and the cooling medium are circulated through independent channels in the second heat exchanger 21, the cooling medium can more easily fill the independent channels to achieve the purpose of cooling the hydrogen, thereby ensuring that the hydrogen when transported to the passenger car 6 can meet the filling temperature requirements, further improving the stability of the precooling system 100 for the hydrogen filling station.

[0070] Accordingly, since the adjacent core assemblies 22 are sealed and connected, and hydrogen can have an independent transport channel, it is ensured that the hydrogen can be safely precooled in the second heat exchange mechanism 2, thereby improving the accuracy and sensitivity of the precooling system 100 used in the hydrogen refueling station to control the hydrogen flow rate, and further improving the success rate of hydrogen refueling.

[0071] In one embodiment, the core assembly 22 includes a flow channel plate. Preferably, a plurality of flow channel plates are provided, and all of them are closely attached together in the vertical direction. Accordingly, a plurality of microchannels 23 in a single direction are provided in each flow channel plate, so that only one substance (hydrogen or cooling medium) is allowed to pass through each flow channel plate, so as to ensure that hydrogen or cooling medium can flow smoothly in the microchannel 23, thereby effectively preventing the risk of hydrogen leakage in the second heat exchange mechanism 2.

[0072] Preferably, the flow channel plate is made of 316L stainless steel. The flow channel plate has good hydrogen embrittlement resistance, thereby effectively preventing safety problems caused by hydrogen overflow, and the flow channel plate also has good pressure resistance, so that it can fully withstand the pressure brought by high-pressure hydrogen to meet the high-pressure gas transportation requirements of the hydrogen refueling station.

[0073] In one embodiment of the present invention, the microchannel 23 is arranged on the flow channel plate by photochemical etching. In this way, on the one hand, hydrogen can flow smoothly in the second heat exchanger 21 through the microchannel 23, thereby improving the flowability of hydrogen; on the other hand, the flow channel plate and the microchannel 23 photochemically etched on the flow channel plate can have an integrally formed structure, thereby improving the stability of the overall structure of the second heat exchanger 21, and further ensuring that the second heat exchanger 21 can have the ability of efficient heat exchange and the ability to accurately control the flow of hydrogen.

[0074] In one embodiment, the microchannel 23 is configured as any one of circular, square and triangular hole structures.

[0075] In this way, sufficient flow channels are provided for hydrogen or cooling medium, so that hydrogen or cooling medium can flow smoothly in the microchannel 23, and since the pore size of the microchannel 23 is small (generally 2 mm), the hydrogen or cooling medium can fill the entire microchannel 23, thereby effectively reducing the flow resistance of the hydrogen or cooling medium in the second heat exchanger 21, and further improving the heat exchange efficiency of the second heat exchanger 21, so that the second heat exchanger 21 can have a good cooling effect on the high-pressure gas of the hydrogen refueling station.

[0076] In one embodiment, Figure 2 As shown, the microchannel 23 includes a first channel portion 231. Preferably, the first channel portion 231 is configured as a linear channel arranged in a transverse direction, and the first channel portion 231 can be used to allow hydrogen to flow.

[0077] It is easy to understand that since the first channel portion 231 is configured as a linear channel, hydrogen can pass through the first channel portion 231 in the first circulation portion 24 (described below) in a shorter time and at a faster speed, thereby being able to more easily meet the passenger car's need to complete 5 kg of hydrogen refueling within 3 to 5 minutes.

[0078] In one embodiment, Figure 2 and 3As shown, the flow channel plate includes a first circulation portion 24. The first circulation portion 24 is composed of a first connecting portion 241 and a second connecting portion 242. The first connecting portion 241 and the second connecting portion 242 are symmetrically arranged, and the first connecting portion 241 and the second connecting portion 242 are connected together to form a connecting body. Accordingly, the connecting body is a structure with good stability and sealing performance.

[0079] In a preferred embodiment, a plurality of first channel portions 231 are provided, and are arranged at intervals in a connection body formed by the first connection portion 241 and the second connection portion 242 .

[0080] In this way, on the one hand, the fluidity and safety of high-pressure hydrogen during the circulation process can be ensured through the connector, and on the other hand, under the action of the second heat exchanger 21, the hydrogen flowing out through the first delivery channel 12 can be well cooled so that the output hydrogen can meet the requirements of rapid refueling of the passenger car 6.

[0081] In another embodiment, the first flow portion 24 may also be configured as an integrally formed structure, which can enhance the stability of the flow channel plate and the safety of use.

[0082] In one embodiment, Figure 2 As shown, the microchannel 23 further includes a second channel portion 232. Preferably, the second channel portion 232 is configured as a curved channel arranged in the longitudinal direction, and the second channel portion 232 can be used to allow the cooling medium to flow.

[0083] It is easy to understand that since the second channel portion 232 is configured as a curved channel, the cooling medium can more easily stay in the second circulation portion 25 (described below) under the action of the second channel portion 232, thereby ensuring that the cooling medium in the second circulation portion 25 can fully cover and cool the hydrogen in the first circulation portion 24, thereby effectively improving the heat exchange capacity of the second heat exchanger 21, so as to achieve the purpose of fully cooling down the hydrogen whose temperature suddenly rises after passing through the first flow channel 12.

[0084] In addition, since the aperture of the microchannel 23 is relatively small (generally 2 mm), the cooling medium can fill the entire second channel portion 232 within the second circulation portion 25, thereby significantly improving the heat dissipation capacity of the second heat exchanger 21 for the hydrogen whose temperature suddenly rises through the first flow channel 12, so that the output hydrogen can meet the requirements of rapid refueling of the passenger car 6.

[0085] In one embodiment, according to the actual requirements of the hydrogen refueling station, the second channel portion 232 may also be configured as a linear channel.

[0086] In one embodiment, the cooling medium is, for example, heat transfer oil. It is easy to understand that any heat transfer medium that can meet high and low temperature operating conditions is sufficient.

[0087] In one embodiment, Figure 2 As shown, the flow channel plate further includes a second flow portion 25. Preferably, the second flow portion 25 is constructed as an integrally formed structure, thereby effectively enhancing the stability of the flow channel plate and the safety of use.

[0088] In a preferred embodiment, a plurality of second channel portions 232 are provided, and are arranged at intervals in the second circulation portion 25 , so as to accommodate more cooling medium.

[0089] In this way, the overall structure of the second circulation portion 25 can have good pressure resistance, thereby ensuring that the cooling medium can be fully distributed in the second channel portion 232 to achieve the purpose of rapid cooling of the high-pressure hydrogen.

[0090] In addition, since the second circulation portion 25 is an integrally formed structure, it can be processed in a more convenient manner, thereby improving production efficiency and facilitating faster production and use.

[0091] In another embodiment, the second circulation portion 25 may also be configured as a split structure, so as to have better installation and disassembly capabilities, thereby improving the portability of the second heat exchanger 21 .

[0092] In one embodiment, the first flow portions 24 and the second flow portions 25 are alternately arranged in the vertical direction.

[0093] In this way, on one hand, two second circulation parts 25 that allow the cooling medium to pass through are provided on both sides of each first circulation part 24 that allows the hydrogen to pass through. In other words, each first circulation part 24 is surrounded by two second circulation parts 25, thereby ensuring that the hydrogen outputted by the second heat exchanger 21 can meet the requirements of the rapid filling of the passenger car 6.

[0094] On the other hand, since the first channel portion 231 in the first circulation portion 24 and the second channel portion 232 in the second circulation portion 25 are vertically distributed, when the first circulation portion 24 and the second circulation portion 25 are alternately arranged in the vertical direction, the second heat exchanger 21 as a whole has a good pressure bearing capacity. In addition, since each first circulation portion 24 is surrounded by two second circulation portions 25, the ability of the first circulation portion 24 to withstand hydrogen is further improved.

[0095] The manufacturing process of the second heat exchanger 21 (microchannel heat exchanger) in the present invention is introduced below.

[0096] First, a photochemical etching method is used to etch microchannels 23 (a first channel portion 231 and a second channel portion 232 ) for the flow of fluid (hydrogen and cooling medium) on the flow channel plate according to the design size specifications.

[0097] Then, a plurality of flow channel plates are stacked vertically layer by layer in an accurate and sealed manner, and the assembled flow channel plates are connected together by a diffusion welding process to form a core assembly 22 .

[0098] The core assembly 22 has the advantages of compact structure and strong structure. The core assembly 22 can effectively and quickly cool and pre-cool the hydrogen whose temperature rises suddenly after passing through the first flow channel 12 through a plurality of microchannels 23 arranged on the flow channel plate, and the core assembly 22 can also accurately control the flow rate of the transported hydrogen.

[0099] Finally, the core assemblies 22 are stacked accurately and sealed layer by layer in the transverse direction, and the assembled core assemblies 22 are installed in the shell through a diffusion welding process to form the second heat exchanger 21 .

[0100] Preferably, since the second heat exchanger 21 is an integrated structure formed by high temperature (1000°C to 1100°C) diffusion welding, the second heat exchanger 21 can be used for precooling of the hydrogen refueling station. In addition, the second heat exchanger 21 has the advantages of reliable structure, high heat exchange efficiency, small footprint and low leakage, so the second heat exchanger 21 can operate safely in a high-pressure hydrogen environment.

[0101] In a preferred embodiment, the hydrogen passing through the second heat exchanger 21 can be controlled within a range of -60°C to -10°C by the cooling medium in the microchannel 23 .

[0102] According to the present invention, Figure 1 As shown, the heat exchange unit further includes a first heat exchange mechanism 3. The first heat exchange mechanism 3 is disposed between the hydrogen storage cylinder 11 and the second heat exchange mechanism 2, and includes a first heat exchanger 31. Preferably, the first heat exchanger 31 in the present invention is a shell-and-tube heat exchanger.

[0103] In a preferred embodiment, the first heat exchanger 31 and the second heat exchanger 21 are arranged in sequence along the flow direction of hydrogen. In other words, the first heat exchanger 31 is the first stage precooling part of the present invention, and the second heat exchanger 21 is the second stage precooling part of the present invention.

[0104] Compared with a hydrogen refueling station with a refueling capacity of 35MPa, a hydrogen refueling station with a refueling capacity of 70MPa can effectively increase the one-time hydrogen refueling amount and refueling time for the passenger car 6, thereby improving the endurance and economy of the passenger car 6 (such as a hydrogen car).

[0105] Although the shell-and-tube heat exchanger in the prior art can withstand the high-pressure working condition of 70MPa, if the shell-and-tube heat exchanger is used as the precooling body of the 70MPa hydrogenation station, the volume of the shell-and-tube heat exchanger will be larger. In addition, since the hydrogen delivery volume per unit time has been doubled from the 35MPa hydrogenation station to the 70MPa hydrogenation station, it is difficult to accurately control the hydrogen flow rate only through the shell-and-tube heat exchanger.

[0106] The present invention adopts a two-stage precooling method, so that the hydrogen gas whose temperature rises suddenly during the flow process can be cooled and lowered in stages. Therefore, the hydrogen gas in the first delivery channel 12 can always maintain a relatively low temperature under the staged cooling effect of the second heat exchanger 21 and the first heat exchanger 31, thereby ensuring the safety and stability of the precooling system 100 for the hydrogen refueling station.

[0107] Furthermore, the flow rate of hydrogen delivery can be precisely controlled through the microchannel 23 of the second heat exchanger 21 to achieve the purpose of flexibly adjusting the hydrogen flow rate, so that the output hydrogen can meet the requirement of rapid filling of the passenger car 6 .

[0108] In addition, the present invention can smoothly complete the task of refueling 5 kg of hydrogen for the passenger car 6 in 3 to 5 minutes under the staged cooling effect of the second heat exchanger 21 and the first heat exchanger 31. Moreover, the present invention also has the ability to operate safely in a high-pressure hydrogen environment, thereby improving the safety and reliability of the precooling system 100 for a hydrogen refueling station.

[0109] In one embodiment, Figure 1 As shown, at least two second delivery channels 4 arranged in parallel are formed at the outlet end of the first heat exchanger 31. Preferably, the second heat exchange mechanism 2 is arranged in the second delivery channel 4, in other words, a second heat exchanger 21 is arranged on each second delivery channel 4.

[0110] In this way, the hydrogen after primary precooling in the first heat exchanger 31 can be diverted in the first delivery channel 12, and the diverted hydrogen flows into the second heat exchanger 21 through the second delivery channel 4 respectively, and this part of the hydrogen can be transported to different passenger cars 6 respectively after secondary precooling in the second heat exchanger 21, so as to realize rapid filling of hydrogen.

[0111] Preferably, the purpose of simultaneously refueling multiple passenger cars 6 can be achieved under the diversion effect of the second delivery channel 4. The output hydrogen can not only meet the requirement of rapid refueling of the passenger cars 6, but also can achieve stability of the output hydrogen and precise control of the flow rate under the action of the second heat exchanger 21.

[0112] In one embodiment, the present invention can be adapted to hydrogen refueling stations at different pressures, such as a 35 MPa hydrogen refueling station and a 70 MPa hydrogen refueling station.

[0113] In addition, since the pressure levels of the hydrogen storage tank (not shown) in the passenger car 6 are different during the actual filling process (depending on the remaining amount of hydrogen in the tank), the temperature change degree of the vehicle-mounted bottle (not shown) in the passenger car 6 during the filling process is different, and thus the filling temperature required for different passenger cars 6 is also different. Therefore, in response to this problem, the present invention can adjust the temperature of the output hydrogen according to the actual working conditions of the remaining hydrogen in the passenger car 6 and through the secondary precooling of the first heat exchanger 31 and the second heat exchanger 21, so that the hydrogen temperature can be reduced to the filling requirement in a shorter time, and the purpose of saving energy consumption for the precooling system 100 of the hydrogen filling station can be further achieved. It is easy to understand that the method of detecting the remaining amount of hydrogen in the hydrogen storage tank is well known to those skilled in the art, so it will not be repeated.

[0114] According to a specific embodiment of the present invention, the first heat exchanger 31 of the present invention can control the temperature of hydrogen within the range of -10°C to 100°C, and the second heat exchanger 21 of the present invention can control the temperature of hydrogen within the range of -60°C to -10°C.

[0115] It is easy to understand that the temperature of hydrogen can be adjusted in stages through the first heat exchanger 31 and the second heat exchanger 21 of the present invention, so that the temperature of hydrogen can be more easily reduced in a short time to meet the filling requirements of the actual working conditions of the passenger car 6, so as to achieve the effect of reducing and saving the energy consumption of the precooling system 100 of the hydrogen filling station.

[0116] In one embodiment, Figure 1 As shown, the first heat exchange mechanism 3 further includes a first sensor 32. Preferably, the first sensor 32 is disposed between the second heat exchanger 21 and the first heat exchanger 31, and is capable of real-time monitoring of the temperature of the hydrogen after being cooled by the first heat exchanger 31, thereby effectively preventing safety accidents caused by the hydrogen temperature process.

[0117] According to the present invention, Figure 1 As shown, the first injection unit further includes a hydrogen compressor 13. Preferably, the hydrogen compressor 13 is disposed between the hydrogen storage bottle 11 and the first heat exchanger 31.

[0118] In this way, the hydrogen flowing from the hydrogen storage bottle 11 can form high-pressure hydrogen in the hydrogen compressor 13 to meet the different filling requirements of the hydrogen filling station. In addition, since the hydrogen pressurized by the hydrogen compressor 13 will pass through the first heat exchanger 31 and perform primary precooling and pass through the second heat exchanger 21 and perform secondary precooling in sequence, the temperature of the high-pressure hydrogen finally output can meet the rapid filling requirements of the passenger car 6.

[0119] In one embodiment, Figure 1 As shown, the first injection unit further includes a stop valve 14. Preferably, the stop valve 14 is disposed at the inlet end of the hydrogen compressor 13, in other words, the stop valve 14 is located between the hydrogen storage bottle 11 and the hydrogen compressor 13, so as to control the flow rate of hydrogen transported outward by the hydrogen storage bottle 11, so as to ensure that the hydrogen can flow smoothly in the second heat exchanger 21 and the first heat exchanger 31.

[0120] Preferably, since the opening or closing stroke of the valve stem (not shown) of the stop valve 14 is relatively short, it can have a very reliable shut-off function, and since the change of the valve seat opening (not shown) is directly proportional to the stroke of the valve disc (not shown), it is very suitable for regulating the flow rate of the fluid.

[0121] In one embodiment, Figure 1 As shown, the first injection unit further includes a safety valve 15. Preferably, the safety valve 15 is disposed on the hydrogen storage bottle 11, so as to control the opening and closing of the hydrogen storage bottle 11. Thus, when a safety accident occurs in the hydrogen storage bottle 11, the source of hydrogen can be cut off immediately through the safety valve 15 to reduce the danger of the accident.

[0122] Preferably, the safety valve 15 is a special valve whose opening and closing parts are in a normally closed state under the action of external force, and which prevents the medium pressure in the pipeline or equipment from exceeding the specified value by discharging the medium to the outside of the system when the medium pressure in the equipment or pipeline exceeds the specified value. This is well known to those skilled in the art.

[0123] In one embodiment, Figure 1 As shown, the second heat exchange mechanism 2 further includes a check valve 26. Preferably, the check valve 26 is disposed at the inlet end of the second heat exchanger 21, so as to ensure that the high-pressure hydrogen cooled by the first heat exchanger 31 can flow to the outside in a fixed direction (direction from the first heat exchanger 31 to the second heat exchanger 21).

[0124] In a preferred embodiment, a check valve 26 is provided on each second delivery channel 4, so as to ensure that the high-pressure hydrogen on each second delivery channel 4 can flow smoothly to the outside.

[0125] In one embodiment, Figure 1 As shown, the second heat exchange mechanism 2 further includes a flow control valve 27. Preferably, the flow control valve 27 is disposed at the inlet of the second heat exchanger 21, so that the flow of the high-pressure hydrogen flowing into the second heat exchanger 21 can be effectively controlled.

[0126] In a preferred embodiment, a flow control valve 27 is provided on each second delivery channel 4 .

[0127] According to the present invention, the precooling system 100 for a hydrogen refueling station further comprises a second injection unit. Figure 1 As shown, the second injection unit includes a hydrogenation hose 51. Preferably, the hydrogenation hose 51 is provided between the passenger car 6 and the second heat exchanger 21. In other words, the hydrogenation hose 51 connects the passenger car 6 and the second heat exchanger 21 together, so that it is easier to achieve the use requirement of hydrogenation of 5 kg within 3 to 5 minutes for the passenger car 6.

[0128] In one embodiment, Figure 1 As shown, the second injection unit further includes a second sensor 52. Preferably, the second sensor 52 is disposed on the hydrogenation hose 51, so as to be able to record the flow rate of the high-pressure hydrogen in real time.

[0129] Compared with the prior art, the present invention has the following advantages.

[0130] First, the present invention sets up a two-stage precooling system in the entire hydrogenation line, and realizes primary precooling through the first heat exchanger 31 and secondary precooling through the second heat exchanger 21, so that the high-pressure hydrogen whose temperature rises suddenly after passing through the hydrogen compressor 13 can be cooled and lowered in stages to meet the requirements of passenger cars for different filling temperatures.

[0131] Compared with a hydrogen refueling station with a filling capacity of 35MPa, a hydrogen refueling station with a filling capacity of 70MPa can effectively increase the one-time hydrogen filling amount and filling time for passenger cars 6, thereby improving the endurance and economy of passenger cars 6 (such as hydrogen energy vehicles). Although the shell-and-tube heat exchanger in the prior art can withstand the high-pressure working condition of 70MPa, if only the shell-and-tube heat exchanger is used as the pre-cooling body of the 70MPa hydrogen refueling station, the volume of the shell-and-tube heat exchanger will be larger. In addition, since the hydrogen delivery volume per unit time has been doubled from the 35MPa hydrogen refueling station to the 70MPa hydrogen refueling station, it will be difficult to accurately control the high-pressure hydrogen flow rate only through the shell-and-tube heat exchanger.

[0132] Compared with the prior art, the present application adopts a two-stage precooling system consisting of a second heat exchanger 21 and a first heat exchanger 31, so that the high-pressure hydrogen in the first delivery channel 12 and the second delivery channel 4 can be maintained at a controllable temperature, thereby ensuring the safety and stability of the precooling system 100 used in the hydrogen refueling station.

[0133] Compared with the traditional single-stage precooling system, the present invention can adaptively adjust the temperature of the output hydrogen through the first heat exchanger 31 and the second heat exchanger 21, so as to meet the refueling requirements of different passenger cars 6, and because it can meet the filling temperature of different passenger cars 6, it effectively reduces and saves the energy consumption of the precooling system 100 used in the hydrogen refueling station.

[0134] Secondly, the high-pressure hydrogen of the present application can be split after the primary precooling in the first heat exchanger 31, thereby flowing to the second heat exchanger 21 on the multiple second delivery channels 4 for secondary precooling.

[0135] Specifically, the hydrogen after primary precooling in the first heat exchanger 31 can be diverted in the first delivery channel 12, and the diverted hydrogen flows into the second heat exchanger 21 through the second delivery channel 4 respectively, and this part of the hydrogen can be transported to different passenger cars 6 after secondary precooling in the second heat exchanger 21 to achieve rapid hydrogen refueling.

[0136] In this way, the purpose of simultaneously refueling multiple passenger cars 6 can be achieved under the diversion effect of the second delivery channel 4. The high-pressure hydrogen output can not only meet the requirements of the refueling time and refueling amount of the passenger cars 6, but also the high-pressure hydrogen output under the action of the second heat exchanger 21 can also have good stability.

[0137] Thirdly, the present application can provide independent channels for high-pressure hydrogen and cooling medium through the microchannels 23 on the flow channel plate, thereby ensuring that the high-pressure hydrogen delivered to the passenger car 6 can meet the refueling temperature requirements, further improving the stability of the precooling system 100 for the hydrogen refueling station.

[0138] Accordingly, since the adjacent core assemblies 22 are sealed and connected, and hydrogen can have an independent transport channel, it is ensured that the hydrogen can be safely precooled in the second heat exchange mechanism 2, thereby improving the accuracy and sensitivity of the precooling system 100 used in the hydrogen refueling station to control the hydrogen flow rate, and further improving the success rate of hydrogen refueling.

[0139] In addition, since the pore size of the microchannel 23 is small (generally 2 mm), the hydrogen or cooling medium can fill the entire microchannel 23, thereby effectively reducing the flow resistance of the hydrogen or cooling medium in the second heat exchanger 21, and further improving the heat exchange efficiency of the second heat exchanger 21, so that the second heat exchanger 21 can have a good cooling effect on the high-pressure gas of the hydrogen refueling station.

[0140] In addition, the present invention can smoothly complete the task of refueling 5 kg of hydrogen for the passenger car 6 in 3 to 5 minutes under the staged cooling effect of the second heat exchanger 21 and the first heat exchanger 31. Moreover, the present invention also has the ability to operate safely in a high-pressure hydrogen environment, thereby improving the safety and reliability of the precooling system 100 for a hydrogen refueling station.

[0141] Fourthly, the present invention can be adapted to hydrogen refueling stations under different pressures, such as 35MPa hydrogen refueling stations and 70MPa hydrogen refueling stations. In addition, the present invention can also adjust the temperature of the output hydrogen according to the actual working condition of the remaining hydrogen in the passenger car 6 and through the secondary precooling of the first heat exchanger 31 and the second heat exchanger 21, so that the output hydrogen meets the refueling requirements of the passenger car 6.

[0142] In addition, the first heat exchanger 31 of the present invention can control the temperature of hydrogen within the range of -10°C to 100°C, and the second heat exchanger 21 of the present invention can control the temperature of hydrogen within the range of -60°C to -10°C. Therefore, the present invention can achieve phased regulation of the temperature of hydrogen through the first heat exchanger 31 and the second heat exchanger 21, so that the temperature of hydrogen can be more easily reduced in a short time to meet the filling requirements of the actual working conditions of the passenger car 6, so as to achieve the purpose of reducing and saving the energy consumption of the precooling system 100 of the hydrogen filling station.

[0143] Fifth, the present application can achieve precise control of the flow rate of the high-pressure hydrogen through the microchannel 23 of the second heat exchanger 21 and the flow control valve 27 arranged at the inlet of the second heat exchanger 21, so as to achieve the purpose of flexibly adjusting the flow rate of the high-pressure hydrogen, so that the output high-pressure hydrogen can meet the requirements of rapid filling of the passenger car 6.

[0144] Sixth, since the volume of the second heat exchanger 21 is smaller than that of the first heat exchanger 31, the use of the second heat exchanger 21 can greatly reduce the site occupation and can improve the heat exchange efficiency and precooling effect of the precooling system 100 for the hydrogen refueling station.

[0145] Seventh, the flow plate is made of 316L stainless steel. The flow plate has good hydrogen embrittlement resistance, which effectively prevents safety problems caused by hydrogen overflow, and the flow plate also has good pressure resistance, so it can fully withstand the pressure brought by high-pressure hydrogen to meet the different high-pressure gas transportation requirements in the hydrogen refueling station.

[0146] In addition, since the second heat exchanger 21 is an integrated structure formed by high temperature (1000°C to 1100°C) diffusion welding, the second heat exchanger 21 can be used for precooling of the hydrogen refueling station. In addition, the second heat exchanger 21 has the advantages of reliable structure, high heat exchange efficiency, small footprint and low leakage, so the second heat exchanger 21 can operate safely in a high-pressure hydrogen environment.

[0147] The above are only preferred embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art can easily make changes or modifications within the disclosure scope of the present invention, and such changes or modifications should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A precooling system for a hydrogen refueling station, comprising: A first injection unit comprises a hydrogen storage bottle (11) arranged in a hydrogen filling station, and a first delivery channel (12) arranged at an outlet end of the hydrogen storage bottle (11), A heat exchange unit arranged on the first delivery channel (12) and used to reduce the temperature of hydrogen, comprising a second heat exchange mechanism (2), and a first heat exchange mechanism (3) arranged between the hydrogen storage bottle (11) and the second heat exchange mechanism (2), The first heat exchange mechanism (3) comprises a first heat exchanger (31), and the second heat exchange mechanism (2) comprises a second heat exchanger (21), a core assembly (22) arranged in the second heat exchanger (21), and a plurality of microchannels (23) arranged in the core assembly (22) and used for guiding fluid.

2. The precooling system for a hydrogen refueling station according to claim 1, characterized in that: The second heat exchanger (21) is a microchannel heat exchanger, and a plurality of sealed core assemblies (22) are arranged in the microchannel heat exchanger in a transverse direction.

3. The precooling system for a hydrogen refueling station according to claim 2, characterized in that: The core assembly (22) comprises a plurality of flow channel plates which are arranged vertically and are sealed and connected to each other, and the microchannels (23) are formed in the flow channel plates by photochemical etching.

4. The precooling system for a hydrogen refueling station according to claim 3, characterized in that: The microchannel (23) is constructed as any one of circular, square and triangular hole structures.

5. The precooling system for a hydrogen refueling station according to claim 4, characterized in that: The microchannel (23) comprises a first channel portion (231) arranged in a transverse direction and configured to guide the hydrogen and configured to be linear, and a second channel portion (232) arranged in a longitudinal direction and configured to guide a cooling medium and configured to be curved.

6. The precooling system for a hydrogen refueling station according to claim 5, characterized in that: The flow channel plate comprises a first circulation portion (24), wherein the first circulation portion (24) comprises a first connecting portion (241) and a second connecting portion (242) which are symmetrically arranged, wherein the first connecting portion (241) and the second connecting portion (242) are connected together to form a connecting body, wherein a plurality of spaced-apart first channel portions (231) are arranged in the connecting body.

7. The precooling system for a hydrogen refueling station according to claim 6, characterized in that: The flow channel plate further comprises a second circulation portion (25), the second circulation portion (25) being constructed as an integrally formed structure, and a plurality of spaced-apart second channel portions (232) are arranged in the second circulation portion (25).

8. The precooling system for a hydrogen refueling station according to claim 7, characterized in that: The first circulation portions (24) and the second circulation portions (25) are arranged alternately in the vertical direction.

9. The precooling system for a hydrogen refueling station according to any one of claims 1 to 8, characterized in that: The first heat exchange mechanism (3) comprises a first sensor (32) for monitoring the temperature of the hydrogen gas and arranged between the second heat exchanger (21) and the first heat exchanger (31), wherein the first heat exchanger (31) is configured as a shell-and-tube heat exchanger.

10. The precooling system for a hydrogen refueling station according to claim 9, characterized in that: The first injection unit further comprises a hydrogen compressor (13) arranged between the hydrogen storage bottle (11) and the first heat exchanger (31), a stop valve (14) arranged at the inlet end of the hydrogen compressor (13), and a safety valve (15) arranged on the hydrogen storage bottle (11).

11. The precooling system for a hydrogen refueling station according to claim 10, characterized in that: At least two second delivery channels (4) arranged in parallel are formed at the outlet end of the first heat exchanger (31), and the second heat exchange mechanism (2) is arranged on the second delivery channel (4).

12. The precooling system for a hydrogen refueling station according to any one of claims 1 to 8, characterized in that: The second heat exchange mechanism (2) further comprises a check valve (26) and a flow control valve (27) which are sequentially arranged at the inlet end of the second heat exchanger (21).

13. The precooling system for a hydrogen refueling station according to any one of claims 1 to 8, characterized in that: The precooling system further comprises a second injection unit, the second injection unit comprising a hydrogenation hose (51) arranged between the passenger car (6) and the second heat exchanger (21), and a second sensor (52) arranged on the hydrogenation hose (51) and used to record the hydrogen flow rate.

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