Low temperature hydrogen heat exchanger integrated with structured catalyst layers

Abstract

The application discloses a low-temperature hydrogen heat exchanger integrated with a structured catalyst layer, heat transfer fins and flow guide fins and sealing strips are arranged between two adjacent partitions to form a cold fluid passage interlayer; the structured catalyst layer, flow guide fins and sealing strips are arranged between two adjacent partitions to form a hot fluid passage interlayer; the cold fluid passage interlayers and the hot fluid passage interlayers are alternately stacked and welded into a heat exchanger core; a cold fluid inlet on the low-temperature hydrogen heat exchanger is connected with a cold fluid outlet through the cold fluid passage interlayer, and a hot fluid inlet on the low-temperature hydrogen heat exchanger is connected with a hot fluid outlet through the hot fluid passage interlayer; the structured catalyst layer comprises a structural matrix formed by stacking multiple metal plates, and the hot fluid passages are uniformly arranged on each metal plate; the inner wall surface of the hot fluid passage is coated with a dispersion carrier and a catalyst coating in sequence. By using the application, the problems of large pressure drop and low overall efficiency of the catalysis and heat exchange integrated low-temperature hydrogen heat exchanger in the hydrogen liquefaction process can be solved.

Description

Technical Field

[0001] This invention relates to the field of hydrogen liquefaction heat exchanger technology, and in particular to a low-temperature hydrogen heat exchanger with an integrated, well-structured catalyst layer. Background Technology

[0002] Hydrogen energy is one of the most promising energy carriers for global decarbonization energy systems. Liquid hydrogen is an excellent energy source with advantages such as high energy density, cleanliness, environmental friendliness, renewability, and high safety, making it suitable for large-scale storage, transportation, and application. The use of liquid hydrogen can reduce dependence on finite resources such as traditional oil and natural gas, reduce environmental pollution, and represents an important direction for future energy development.

[0003] Hydrogen molecules can be classified into two types based on the spin state of the hydrogen nuclei: orthohydrogen and parahydrogen. At room temperature, hydrogen gas consists of 75% orthohydrogen and 25% parahydrogen. As the temperature decreases to 20K, the proportion of parahydrogen gradually increases until, at liquid hydrogen temperature, the equilibrium concentration of parahydrogen approaches 100%. Because the spontaneous conversion rate between orthohydrogen and parahydrogen is extremely slow, normal hydrogen still contains a significant amount of orthohydrogen after direct liquefaction. Since the heat released during the conversion of orthohydrogen and parahydrogen is higher than the latent heat of vaporization of liquid hydrogen, the conversion of orthohydrogen to parahydrogen in liquid hydrogen will lead to evaporation losses. Therefore, during the liquefaction process, using a highly efficient orthohydrogen-parahydrogen conversion catalyst can accelerate the conversion rate, allowing the orthohydrogen-parahydrogen conversion to occur simultaneously with hydrogen liquefaction, thereby reducing evaporation losses and improving the storage stability of liquid hydrogen.

[0004] The integrated catalytic and heat exchange cryogenic hydrogen heat exchanger is a key piece of equipment in large-scale hydrogen liquefaction technology. Compared with the traditional scheme where the catalyst and heat exchanger are arranged separately, its advantages are: integrated design, compact structure, small footprint, and low installation and maintenance costs; it can simultaneously cool and convert hydrogen, greatly improving liquefaction efficiency and reducing energy loss and equipment costs; it can directly send liquefied hydrogen into the storage tank, greatly reducing hydrogen evaporation loss during liquefaction, reducing hydrogen evaporation and leakage, and improving the efficiency of hydrogen storage and transportation.

[0005] For example, Chinese patent document CN114353563A discloses a temperature-zone combined low-temperature hydrogen plate-fin heat exchanger for continuous conversion of n-parahydrogen. It includes multiple heat exchangers connected in combination. Each heat exchanger body consists of multiple layers of uniformly arranged heat exchange fins and baffles. One end of the heat exchanger body has a hot fluid inlet and a cold fluid outlet, while the other end has a hot fluid outlet and a cold fluid inlet. The hot fluid inlet is connected to the hot fluid outlet through a hot fluid channel within the heat exchanger body, and the cold fluid outlet is connected to the cold fluid inlet through a cold fluid channel within the heat exchanger body. Each heat exchanger corresponds to a heat exchange temperature zone along the temperature gradient direction. Each heat exchanger's hot fluid channel contains at least one filling zone, and different highly active n-parahydrogen conversion catalysts are placed in different filling zones.

[0006] However, what is currently disclosed is that numerous catalyst particles with certain particle size and shape are randomly stacked and filled in the heat exchanger. Its most prominent feature is the uneven distribution of catalyst particles, which leads to uneven flow of reaction fluid, excessive pressure drop through the catalyst, low overall efficiency, and high operating costs due to the large pressure drop. Summary of the Invention

[0007] This invention provides a low-temperature hydrogen heat exchanger with an integrated, structured catalyst layer, which can solve the problems of high pressure drop and low overall efficiency in integrated low-temperature hydrogen heat exchangers that combine catalysis and heat exchange during hydrogen liquefaction.

[0008] A low-temperature hydrogen heat exchanger with an integrated structured catalyst layer, the low-temperature hydrogen heat exchanger comprising flow guide fins, seals, a structured catalyst layer, baffles and heat transfer fins.

[0009] A cold fluid channel interlayer is formed by placing heat transfer fins, flow guiding fins, and seals between two adjacent partitions; a hot fluid channel interlayer is formed by placing a regularly structured catalyst layer, flow guiding fins, and seals between two adjacent partitions.

[0010] The cold fluid channel interlayer and the hot fluid channel interlayer are stacked alternately and welded into a heat exchanger core and integrated into the low-temperature hydrogen heat exchanger; the cold fluid inlet end cap pipe on the low-temperature hydrogen heat exchanger is connected to the cold fluid outlet end cap pipe through the cold fluid channel interlayer, and the hot fluid inlet end cap pipe on the low-temperature hydrogen heat exchanger is connected to the hot fluid outlet end cap pipe through the hot fluid channel interlayer.

[0011] The well-structured catalyst layer comprises a structural matrix composed of multiple layers of stacked metal plates, each layer of metal plates having uniformly spaced grooves forming a hot fluid channel; the inner wall of the hot fluid channel is sequentially coated with a dispersion carrier and a catalyst coating.

[0012] Furthermore, the manufacturing process of the low-temperature hydrogen heat exchanger is as follows:

[0013] S1. Grooves are cut into metal plates, and multiple layers of metal plates are stacked to create a structural base with a regular structure; instantaneous liquid phase diffusion welding technology is used between each layer of metal plates in the range of 910 to 1012℃ to make the multiple layers of plates a whole;

[0014] S2, fabricate hot fluid channel interlayer and cold fluid channel interlayer, alternately stack the cold fluid channel interlayer and hot fluid channel interlayer, braze them into heat exchanger core in the range of 600-750℃ and integrate them into the heat exchanger to form an integrated heat exchanger with structural matrix.

[0015] S3. After the heat exchanger is initially integrated, the inner wall of the hot fluid channel is coated with a coating liquid containing a dispersion carrier using an impregnation-pull method or a circulation pumping method. Then, it is fully dried at 100-150°C and sintered in a furnace at 450-650°C. Multiple coating steps are performed until the loading of the dispersion carrier meets the requirements.

[0016] S4. After the dispersion carrier is loaded, the coating liquid of the catalyst coating is applied to the surface of the dispersion carrier in the hot fluid channel by circulating pumping, and then dried thoroughly. Multiple coating steps are performed until the catalyst loading reaches the required level. After the catalyst is activated at 100-200℃, a low-temperature hydrogen heat exchanger with an integrated and regular catalyst layer is obtained.

[0017] In step S1, the material of the structural substrate (111) is stainless steel or FeCrAl alloy; when using instantaneous liquid phase diffusion welding technology, intermetallic compound Ni-Ti, intermetallic compound Cu-Zn or metallic glass Ni-14B-7Si are used as intermediate interlayer filling materials.

[0018] Diffusion welding uses a material with a lower melting point than the structural matrix material as an intermediate layer. When heated to the bonding temperature, the intermediate layer melts and forms an instantaneous liquid film on the bonding surface. During the heat preservation process, as the low-melting-point components diffuse into the base material, the thickness of the liquid film decreases until it disappears. After a certain period of heat preservation, the composition becomes homogenized.

[0019] Preferably, a specially treated FeCrAl alloy is used as the structural matrix because its surface enrichment of aluminum (mainly in the form of α-Al2O3) can improve the adhesion to the dispersed Al2O3 layer.

[0020] Preferably, the material of the dispersion carrier is alumina. Before coating, the inner wall surface of the hot fluid channel needs to be treated with acid, alkali or acetone to remove surface impurities.

[0021] Furthermore, in step S3, the specific steps for coating the dispersion carrier are as follows:

[0022] S301, first prepare the AlOOH sol by mixing nitric acid and pseudoboehmite in a molar ratio [H + ] / [Al 3+ Mix the ingredients in a ratio between 0.08 and 0.09, stir well, and then age for 24 to 48 hours to allow for a full reaction.

[0023] The raw materials for preparing AlOOH sol can be organic aluminum alkoxide, inorganic aluminum salts and metallic aluminum, nano alumina, boehmite, aluminum hydroxide latex monomers, etc.

[0024] S302, the pore expander and binder are made of PVA solution. The aged slurry is mixed with 2-4% PVA by mass and stirred to make a coating solution. The coating solution of the dispersion carrier is applied to the inner wall surface of the hot fluid channel using the dip-coating method or the circulating pump method.

[0025] After coating, allow it to dry thoroughly, first at room temperature, then under vacuum at 100–150°C for 200–500 minutes.

[0026] S303. The dried integrated heat exchanger is placed in a tube furnace for sintering at a temperature of 450–650°C for 120–480 minutes. The heat exchanger is then removed, and the preparation is complete.

[0027] The coating solution of the catalyst coating is obtained by mixing catalytic active ingredients, catalytic promoters and binders; the catalytic active ingredients include at least one of hydrated iron oxide, Fe(OH)3 and Fe3O4, the catalytic promoters include aluminum oxide, and the binders include SiO2 sol and / or Al2O3 sol.

[0028] In step S4, after the coating liquid for the catalyst coating is applied, the catalyst coating is purged by compressed air at a purging pressure of less than 3 MPa to make the hot fluid channel of the heat exchanger purged so that the catalyst coating peeling rate is less than 5%.

[0029] Alternatively, the heat transfer fins may be of a straight, corrugated, porous, or serrated structure.

[0030] Alternatively, the hot fluid channels on the structural substrate can be straight, corrugated, semi-circular, or serrated. Furthermore, fins can be added to the surface of the hot fluid channels on the structural substrate. This structure can increase the contact area between the hot fluid hydrogen and the catalyst, enhancing the catalytic effect.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. In traditional particle-filled reactors, frequent changes in fluid flow direction cause significant momentum loss. This invention, by incorporating a structured catalyst in a low-temperature heat exchanger, eliminates the uneven contact between reactants and the catalyst surface caused by various inhomogeneities within the catalyst layer (catalyst structure distribution, material distribution, temperature distribution, and pressure distribution, etc.), thereby enhancing the heat and mass transfer process in the heat exchanger, reducing pressure drop, and decreasing operating costs.

[0033] 2. The hot fluid channel of this invention integrates a structured catalyst, and its matrix is ​​made of an alloy material with high thermal conductivity. Compared with traditional particle-filled catalyst layers, the new structure has a similar function to heat exchange fins, thus resulting in a more uniform temperature distribution in the catalyst layer, which is beneficial for improving the catalytic conversion rate and cooling performance.

[0034] 3. In this invention, the structured catalyst has a large porosity (0.7-0.9), which is higher than that of traditional particle-filled catalysts (generally less than 0.5), which helps to improve reaction activity and conversion efficiency. On the other hand, compared with the tortuous fluid flow path of traditional particle-filled catalysts, the flow path in the structured catalyst is more unobstructed, which can significantly improve the catalytic effect.

[0035] 4. The random flow and chaotic characteristics in traditional packed particle catalyst heat exchangers greatly limit the scale-up, simulation and design accuracy of conventional heat exchangers; however, the present invention does not have these limitations. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of a low-temperature hydrogen heat exchanger with an integrated, well-structured catalyst layer according to the present invention.

[0037] Figure 2 This is a schematic diagram of the internal structure of the ordered catalyst layer in this invention;

[0038] Figure 3 This is a flowchart illustrating the preparation process of the low-temperature hydrogen heat exchanger with an integrated structured catalyst layer in this invention.

[0039] Figure 4 This is a flowchart illustrating the manufacturing process of the structural matrix in the well-structured catalyst layer of the present invention.

[0040] Figure 5 This is a schematic diagram of different fin types of a low-temperature hydrogen heat exchanger in an embodiment of the present invention;

[0041] Figure 6 This is a schematic diagram of different structural matrix types in the embodiments of the present invention.

[0042] In the figure: Cold fluid inlet end cap pipe-101, hot fluid outlet end cap pipe-102, flow guide fins-103, seal-104, structured catalyst layer-105, baffle-106, heat transfer fins-107, cover plate-108, hot fluid inlet end cap pipe-109, cold fluid outlet end cap pipe-110, structural matrix-111, dispersion carrier-112, catalyst coating-113, metal matrix plate-114, intermediate interlayer-115. Detailed Implementation

[0043] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be noted that the embodiments described below are intended to facilitate the understanding of the present invention and do not constitute any limitation thereof.

[0044] A low-temperature hydrogen heat exchanger integrating a structured catalyst layer integrates a conventional heat exchanger with a structured catalyst layer. The macroscopic structure of the heat exchanger includes a cold fluid inlet end cap 101, a hot fluid outlet end cap 102, guide fins 103, a seal 104, a structured catalyst layer 105, a baffle 106, heat transfer fins 107, a cover plate 108, a hot fluid inlet end cap 109, and a cold fluid outlet end cap 110.

[0045] like Figure 2 As shown, the well-structured catalyst layer 105 consists of a structural matrix 111, a dispersion support 112, and a catalyst coating 113. The structural matrix 111 is composed of multiple layers of plates, each layer having channels that are uniformly sized and distributed on a macroscopic scale. The dispersion support 112 is in contact with the structural matrix 111 and is coated on the surface of the structural matrix. The catalyst coating 113 is in contact with the dispersion support 112 and is coated on the surface of the dispersion support 112.

[0046] A heat transfer fin 107, a regular structure catalyst layer 105, a flow guiding fin 103, and a seal 104 are placed between two adjacent partitions to form a sandwich layer, called a cold / hot fluid channel sandwich layer. Such cold / hot fluid channel sandwich layers are arranged in an alternating stacking manner and brazed into a whole to form the heat exchanger core.

[0047] One end of the heat exchanger is provided with a hot fluid inlet end cap 109 and a cold fluid outlet end cap 110, while the other end of the heat exchanger is provided with a cold fluid inlet end cap 101 and a hot fluid outlet end cap 102. The cold fluid inlet end cap 101 is connected to the cold fluid outlet end cap 110 through a cold fluid channel interlayer, and the hot fluid inlet end cap 109 is connected to the hot fluid outlet end cap 102 through a hot fluid channel interlayer.

[0048] like Figure 3 As shown, the fabrication process steps of the low-temperature hydrogen heat exchanger with an integrated, structured catalyst layer are as follows:

[0049] S1, Grooved metal plates are stacked to create a regular structural substrate 111. Each plate layer is bonded together using instantaneous liquid phase diffusion welding technology within the temperature range of 910–1012℃, making the multiple plates a single unit.

[0050] S2, In the manufacturing of the heat exchanger, heat transfer fins 107, flow guide fins 103, and seals 104 are placed between two adjacent partitions 106 to form a cold fluid channel interlayer; a regular structure catalyst layer 105, flow guide fins 103, and seals 104 are placed between two adjacent partitions 106 to form a hot fluid channel interlayer.

[0051] The cold fluid channel jacket and the hot fluid channel jacket are alternately stacked in the low temperature heat exchanger, and the heat exchanger core is brazed in the range of 600 to 750°C. Other steps are the same as the traditional heat exchanger manufacturing process, forming an integrated heat exchanger with structural substrate 111.

[0052] S3. After the heat exchanger is initially integrated, the coating solution of the dispersion carrier 112 is introduced by immersion pulling or through a hot fluid channel circulation pump. Then, it is thoroughly dried at 100-150℃ and sintered in a furnace at 450-650℃. The coating process is repeated multiple times until the dispersion carrier loading reaches the required level.

[0053] S4, after loading onto the dispersion carrier 112, the catalyst coating solution 113 is circulated into the carrier through a hot fluid channel and thoroughly dried. This coating process is repeated multiple times until the required catalyst loading is achieved. After activation at 100–200°C, a heat exchanger with a regular catalyst structure is obtained.

[0054] like Figure 4 As shown, the structural substrate 111 can be made of stainless steel, FeCrAl alloy, or other alloy metal substrate plates 114. Each plate layer is bonded together as a single unit using instantaneous liquid phase diffusion welding technology within the temperature range of 910–1012°C. The diffusion welding uses a material with a lower melting point than the plate material as an intermediate interlayer 115. When heated to the bonding temperature, the intermediate layer melts, forming an instantaneous liquid film on the bonding surface. During the holding process, as the low-melting-point components diffuse into the base material, the thickness of the liquid film decreases until it disappears. After a certain holding time, the composition is homogenized. The instantaneous liquid phase diffusion welding technology uses alloys or metallic glass such as Ni-14B-7Si (mass fraction) with the same or similar composition as the plates as the intermediate interlayer filler material. A specially treated FeCrAl alloy is preferred as the structural substrate because its surface enrichment (mainly in the form of α-Al2O3) improves the adhesion to the dispersed Al2O3 layer.

[0055] The dispersion carrier 112 is preferably alumina, and a layer of dispersion carrier 112 is prepared by coating the surface of the internal structural substrate 111 of the heat exchanger using the sol-gel method. Before coating, the surface of the internal structural substrate 111 of the heat exchanger needs to be treated with acid, alkali or acetone to remove impurities such as oil from the metal surface.

[0056] The specific steps for coating the dispersion carrier are as follows:

[0057] (a) First, prepare the AlOOH sol by mixing nitric acid and pseudoboehmite in a molar ratio [H... + ] / [Al 3+ Mix the ingredients in a ratio between 0.08 and 0.09, stir well, and then age for 30 to 48 hours to allow for a full reaction.

[0058] The raw materials for preparing AlOOH sol can be organic aluminum alkoxides, inorganic aluminum salts and metallic aluminum, nano-alumina, boehmite, aluminum hydroxide latex monomers, etc.

[0059] (b) The pore-expanding agent and adhesive are PVA solution. The aged slurry is mixed with 2-4% PVA by mass and stirred to make a coating solution. The cleaned heat exchanger with structure substrate 111 is placed into the prepared substrate coating solution and coated by dip-coating method. Each dip is 2 minutes, followed by 20 seconds of air drying. After coating, it is thoroughly dried. First, it is dried at room temperature, and then vacuum dried at 100-150℃ for 200-500 minutes.

[0060] (c) Place the dried heat exchanger into a tube furnace for sintering at a temperature of 450–650°C for 120–480 minutes. The heat exchanger is then removed and the preparation is complete.

[0061] The catalyst coating 113 comprises a catalytically active component, a catalytic promoter, and a binder, which are mixed to obtain a catalyst coating slurry. The catalytic coating slurry is applied to the surface of the dispersion carrier 112 within a heat exchanger using a vacuum coating apparatus to obtain a molded body. Furthermore, after purging the structured catalyst layer 105 with compressed air at a purging pressure below 3 MPa, the catalyst coating 113 exhibits a peeling rate of less than 5%. The catalytically active component includes common neutral and secondary hydrogen catalysts such as hydrated iron oxide, Fe(OH)3, or Fe3O4; the catalytic promoter includes aluminum oxide; and the binder includes SiO2 sol and / or Al2O3 sol.

[0062] like Figure 5 As shown in the figure, the heat transfer fins 107 can adopt the following structures: (a) straight type, (b) corrugated type, (c) porous type, and (d) serrated type.

[0063] like Figure 6As shown in the figure, the internal channels of the structural substrate 111 can adopt the following structures: (a) is straight, (b) is corrugated, (c) is semi-circular, (d) is serrated, and (e) indicates that fins can be added to the surface of the internal channels of the structural substrate 111.

[0064] As shown in Table 1, the well-structured catalyst layer used in this invention exhibits superior performance compared to traditional packed catalysts in terms of porosity, radial effective thermal conductivity, and pressure drop. Specifically, porosity is increased by approximately two times; radial effective thermal conductivity is increased by one to two orders of magnitude, thereby enhancing the heat transfer efficiency of the heat exchanger; and pressure drop is reduced by two to three orders of magnitude, thus reducing operating costs.

[0065] Table 1 Comparison of characteristic parameters between structured catalyst layers and packed catalysts.

[0066]

[0067] Example 1

[0068] The metal plates are made of FeCrAl alloy, with Ni-14B-7Si (mass fraction) metallic glass as the intermediate layer. Instantaneous liquid-phase diffusion welding technology is used within the temperature range of 982–1012℃ to integrate the multi-layered plates into a single structural substrate. In heat exchanger manufacturing, the structural substrate, heat transfer fins, and baffles are alternately stacked within the low-temperature heat exchanger. The heat exchanger core is integrated using silver brazing within the temperature range of 650–750℃. Other steps are the same as traditional heat exchanger manufacturing processes, forming an integrated heat exchanger with a structural substrate. After initial integration, a dispersion carrier coating solution is introduced using either an impregnation-pull method or by circulating pumping through a hot fluid channel. The solution is then thoroughly dried at 100–150℃ and sintered in a furnace at 450–650℃. This coating process is repeated multiple times until the required dispersion carrier loading is achieved. After the dispersion carrier is loaded, a catalyst coating solution is circulated through a hot fluid channel and thoroughly dried. This coating process is repeated multiple times until the required catalyst loading is achieved. After activation at 100–200 °C, a heat exchanger with a regular catalyst structure is obtained.

[0069] Example 2

[0070] The metal plates are made of stainless steel, with the intermetallic compound Ni-Ti as the intermediate layer. A transient liquid-phase diffusion welding technique is used within the temperature range of 1310–1330℃ to integrate the multi-layer plates into a single structural substrate. In heat exchanger manufacturing, the structural substrate, heat transfer fins, and baffles are alternately stacked within the low-temperature heat exchanger. The heat exchanger core is integrated using aluminum-magnesium alloy brazing within the temperature range of 620–650℃. Other steps are the same as traditional heat exchanger manufacturing processes, forming an integrated heat exchanger with a structural substrate. After initial integration, a dispersion carrier coating solution is introduced using either an impregnation-pull method or by circulating pumping through a hot fluid channel. The solution is then thoroughly dried at 100–150℃ and sintered in a furnace at 450–650℃. This coating process is repeated multiple times until the required dispersion carrier loading is achieved. After the dispersion carrier is loaded, a catalyst coating solution is circulated through a hot fluid channel and thoroughly dried. This coating process is repeated multiple times until the required catalyst loading is achieved. After activation at 100–200 °C, a heat exchanger with a regular catalyst structure is obtained.

[0071] Example 3

[0072] The metal plates are made of stainless steel, with intermetallic compounds Cu-Zn as the intermediate interlayer. A transient liquid-phase diffusion welding technique is used within the temperature range of 910–930℃ to integrate the multi-layer plates into a single structural substrate. In heat exchanger manufacturing, the structural substrate, heat transfer fins, and baffles are alternately stacked within the low-temperature heat exchanger. The heat exchanger core is integrated using aluminum-silicon alloy brazing within the temperature range of 610–640℃. Other steps are the same as traditional heat exchanger manufacturing processes, forming an integrated heat exchanger with a structural substrate. After initial integration, a dispersion carrier coating solution is introduced using either an impregnation-pull method or by circulating pumping through a hot fluid channel. The solution is then thoroughly dried at 100–150℃ and sintered in a furnace at 450–650℃. This coating process is repeated multiple times until the required dispersion carrier loading is achieved. After dispersion carrier loading, a catalyst coating solution is circulated through a hot fluid channel and thoroughly dried. This coating process is repeated multiple times until the required catalyst loading is achieved. After activation at 100–200 °C, a heat exchanger with a regular catalyst structure is obtained.

[0073] The embodiments described above provide a detailed explanation of the technical solutions and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, additions, and equivalent substitutions made within the scope of the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A low-temperature hydrogen heat exchanger with an integrated, structured catalyst layer, characterized in that, The low-temperature hydrogen heat exchanger includes flow guide fins (103), seals (104), a structured catalyst layer (105), a partition (106), and heat transfer fins (107). A cold fluid channel interlayer is formed by placing heat transfer fins (107), flow guiding fins (103), and seals (104) between two adjacent partitions (106); a hot fluid channel interlayer is formed by placing a regular structure catalyst layer (105), flow guiding fins (103), and seals (104) between two adjacent partitions (106). The cold fluid channel interlayer and the hot fluid channel interlayer are stacked alternately, welded into a heat exchanger core and integrated into a low-temperature hydrogen heat exchanger. The cold fluid inlet end cap pipe (101) on the low-temperature hydrogen heat exchanger is connected to the cold fluid outlet end cap pipe (110) through the cold fluid channel interlayer, and the hot fluid inlet end cap pipe (109) on the low-temperature hydrogen heat exchanger is connected to the hot fluid outlet end cap pipe (102) through the hot fluid channel interlayer. The well-structured catalyst layer (105) includes a structural matrix (111) formed by stacking multiple layers of metal plates, with grooves uniformly provided on each layer of metal plates to form a hot fluid channel; the inner wall of the hot fluid channel is coated with a dispersion carrier (112) and a catalyst coating (113) in sequence. The manufacturing process of the low-temperature hydrogen heat exchanger is as follows: S1, slot the metal plate and stack multiple layers of metal plates to make a regular structural base (111); use instantaneous liquid phase diffusion welding technology between each layer of metal plate in the range of 910~1012℃ to make the multiple layers of plates into a whole; S2, fabricate hot fluid channel interlayer and cold fluid channel interlayer, alternately stack the cold fluid channel interlayer and hot fluid channel interlayer, braze them into heat exchanger core in the range of 600~750℃ and integrate them in the heat exchanger to form an integrated heat exchanger with structural substrate (111). S3. After the heat exchanger is initially integrated, the inner wall of the hot fluid channel is coated with a coating liquid of the dispersion carrier (112) using the immersion lifting method or the circulation pumping method. Then, it is fully dried at 100~150℃ and then placed in a furnace at 450~650℃ for sintering. Multiple coating steps are performed until the loading of the dispersion carrier (112) reaches the required level. S4, after the dispersion carrier (112) is loaded, the coating liquid of the catalyst coating (113) is coated on the surface of the dispersion carrier (112) in the hot fluid channel by means of circulation pumping, and then fully dried; multiple coating steps are performed until the catalyst loading reaches the required level; after the catalyst is activated at 100~200℃, a low-temperature hydrogen heat exchanger with an integrated and regular structure catalyst layer is obtained.

2. The low-temperature hydrogen heat exchanger with an integrated, structured catalyst layer according to claim 1, characterized in that, In step S1, the material of the structural substrate (111) is stainless steel or FeCrAl alloy; when using instantaneous liquid phase diffusion welding technology, intermetallic compound Ni-Ti, intermetallic compound Cu-Zn or metallic glass Ni-14B-7Si are used as intermediate interlayer filling materials.

3. The low-temperature hydrogen heat exchanger with an integrated, structured catalyst layer according to claim 1, characterized in that, The material of the dispersion carrier (112) is alumina. Before coating, the inner wall of the hot fluid channel needs to be treated with acid, alkali or acetone to remove surface impurities.

4. The low-temperature hydrogen heat exchanger with an integrated, structured catalyst layer according to claim 1, characterized in that, In step S3, the specific steps for coating the dispersion carrier are as follows: S301, first prepare the AlOOH sol by mixing nitric acid and pseudoboehmite in a molar ratio [H + ] / [Al 3+ Mix the ingredients in a ratio between 0.08 and 0.09, stir well, and then age for 24 to 48 hours to allow for a complete reaction. S302, the pore expander and binder are made of PVA solution. The aged slurry is mixed with 2-4% PVA by mass and stirred to make a coating liquid. The coating liquid of the dispersion carrier (112) is applied to the inner wall of the hot fluid channel by dip-pull method or circulation pumping method. After coating, allow it to dry thoroughly, first at room temperature, then under vacuum at 100-150°C for 200-500 minutes. S303. The dried integrated heat exchanger is placed in a tube furnace for sintering at a temperature of 450~650℃ for 120~480 minutes. The heat exchanger is then removed and the preparation is complete.

5. The low-temperature hydrogen heat exchanger with an integrated, structured catalyst layer according to claim 1, characterized in that, The coating solution of the catalyst coating (113) is obtained by mixing catalytic active ingredients, catalytic promoters and binders; the catalytic active ingredients include at least one of hydrated iron oxide, Fe(OH)3 and Fe3O4, the catalytic promoters include aluminum oxide, and the binders include SiO2 sol and / or Al2O3 sol.

6. The low-temperature hydrogen heat exchanger with an integrated, well-structured catalyst layer according to claim 1, characterized in that, In step S4, after the coating liquid for coating the catalyst coating (113) is applied, the catalyst coating (113) is purged by compressed air at a purging pressure of less than 3 MPa to make the detachment rate of the catalyst coating (113) less than 5%.

7. The low-temperature hydrogen heat exchanger with an integrated, structured catalyst layer according to claim 1, characterized in that, The heat transfer fins (107) are of the following types: straight, corrugated, porous or serrated.

8. The low-temperature hydrogen heat exchanger with an integrated, structured catalyst layer according to claim 1, characterized in that, The hot fluid channels on the structural substrate (111) adopt a straight, corrugated, semi-circular or sawtooth structure.

9. The low-temperature hydrogen heat exchanger with an integrated, structured catalyst layer according to claim 1, characterized in that, A finned structure is added to the surface of the hot fluid channel on the structural substrate (111).

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