A stacked hydrogen purification membrane reactor

Abstract

The present invention discloses a stacked hydrogen purification membrane reactor. The membrane reactor is mainly composed of an upper cover plate, a first graphite gasket, a first palladium-copper alloy film, a first graphite gasket, a first metal copper mesh, a second graphite gasket, a water-gas shift reaction chamber, a second graphite gasket, a second metal copper mesh, a first graphite gasket, a second palladium-copper alloy film, a first graphite gasket and a lower cover plate, which are stacked in sequence from top to bottom. An outlet for an external vacuum pump is provided in the upper cover plate, and a lower cover plate gas inlet and a tail gas outlet are provided in the lower cover plate. A reaction chamber gas inlet and a reaction chamber gas outlet are provided at both ends of the water-gas shift reaction chamber. The reaction chamber gas inlet is connected to the mixed gas, and the reaction chamber gas outlet is connected to the lower cover plate gas inlet through a rubber conduit, and the membrane reactor is fastened by bolts. The present invention converts carbon monoxide in the mixed gas into hydrogen, removes carbon monoxide and increases hydrogen production at the same time, has a high degree of modularization, low expansion cost, and a wide range of applications.

Description

Technical Field

[0001] The invention belongs to the field of renewable energy and relates to a hydrogen purification device for hydrogen production products from methanol reforming, in particular to a stacked hydrogen purification membrane reactor. Background Art

[0002] With the development of society, human demand for energy continues to increase, which leads to the massive consumption of petroleum fossil fuels. The extensive use of petroleum fossil fuels will lead to serious environmental pollution, and petroleum fossil fuels are non-renewable resources with limited reserves. Therefore, humans are in urgent need of green and environmentally friendly renewable energy. Hydrogen energy, as a renewable, high-utilization, and abundant green energy, is an ideal energy source to replace petroleum fossil fuels.

[0003] The direct hydrogen storage and transmission process faces problems such as high risk, high energy consumption and low hydrogen storage density. Methanol, as a good hydrogen storage carrier, has the characteristics of easy carrying and transportation, high hydrogen storage density, wide sources and renewability. Methanol can be used on-site through a hydrogen production reactor, which is an effective way to solve the problems of direct hydrogen storage and transmission.

[0004] Hydrogen fuel cells are one of the main ways to utilize hydrogen energy. The purity of hydrogen used in hydrogen fuel cells is required to be above 99.999%. However, the existing methanol steam reforming hydrogen production reaction products contain H2, CO, and CO2, and the purity of the hydrogen produced is far from meeting the needs of hydrogen fuel cells. At the same time, CO in the reforming product will poison the platinum-based catalyst in the hydrogen fuel cell and make it ineffective, so the CO concentration must be reduced to below 10ppm. Therefore, the on-site hydrogen production products of methanol cannot be directly applied to hydrogen fuel cells, which limits the application of on-site hydrogen production of methanol. In order to achieve the connection between on-site hydrogen production and hydrogen use, it is crucial to improve the purity of H2 and reduce the CO concentration in the hydrogen production products of methanol steam reforming.

[0005] A Chinese utility model patent (application number 202121083998.8) discloses a filtering mechanism of a hydrogen purification device, including an adsorption structure and a filtering structure. H2 enters from the bottom of the adsorption structure and passes upward through the adsorption structure, and the adsorption structure adsorbs the water vapor and particulate impurities mixed in the hydrogen; then H2 enters the filtering structure again, and CO2 in H2 is separated through a palladium-silver alloy membrane to obtain H2 with higher purity. The problem of poor filtering effect of hydrogen purification filtering devices in the prior art is improved. A Chinese invention patent (application number 201910203234.9) discloses a hydrogen purification device with a stacked structure, including a filtering device and a heating device. A palladium-silver alloy membrane supported by a stainless steel filter is used to filter CO2 and purify H2, and a heating device is used to heat the filtering device to avoid "hydrogen embrittlement" of the palladium-silver alloy membrane. Under high temperature and high pressure conditions, the structure of the filtering device and the heating device is improved, which not only has a high structural strength but also can effectively avoid problems such as "hydrogen embrittlement".

[0006] Neither of the above two technical solutions takes into account the limited purification effect of the palladium alloy membrane. Although high-purity H2 can be obtained through the palladium alloy membrane, there will still be a very small part of the impurities that cannot be removed by membrane separation alone. If the impurities contain CO, even if the impurity content is very small, the hydrogen fuel cell will fail; at the same time, the hydrogen adsorption sites on the palladium alloy membrane are limited. When the intake flow rate is large, part of the H2 cannot pass through the palladium alloy membrane and is discharged with the exhaust gas, which leads to the waste of H2. Although the invention patent with application number 201910203234.9 uses a stacked device structure, its components are not modularized. In the disclosed patents, no multi-modular hydrogen purification membrane reactor has been found that can take into account CO removal, H2 purification and recovery, and multi-module hydrogen purification membrane reactors at the same time. The prior art lacks a stacked hydrogen purification membrane reactor that can completely remove CO, improve the purity of H2, and increase the output of H2, and can freely expand the modules according to the working conditions to expand the scope of use. Summary of the invention

[0007] In order to solve the problems of low purity of H2, high CO content, and inability of the reformed product to be directly used in hydrogen fuel cells in the existing methanol reforming hydrogen production products, the purpose of the present invention is to provide a stacked hydrogen purification membrane reactor. The structure of the membrane reactor is modularly designed, and multiple water-gas shift reactions and multiple membrane separations are achieved by superimposing multiple modules, thereby improving the yield and purity of H2.

[0008] The technical solution adopted by the present invention is:

[0009] It is mainly composed of an upper cover plate, a first graphite gasket, a first palladium-copper alloy film, a first graphite gasket, a first metal copper mesh, a second graphite gasket, a water-gas shift reaction chamber, a second graphite gasket, a second metal copper mesh, a first graphite gasket, a second palladium-copper alloy film, a first graphite gasket and a lower cover plate, which are stacked in sequence from top to bottom;

[0010] The membrane reactor separates carbon monoxide and hydrogen in the mixed gas through the first palladium-copper alloy membrane and the second palladium-copper alloy membrane, and converts carbon monoxide into hydrogen, thereby increasing the hydrogen production while removing carbon monoxide from the mixed gas, thereby achieving the purification and utilization of hydrogen.

[0011] The upper cover plate is provided with an outlet for an external vacuum pump, the lower cover plate is provided with a lower cover plate gas inlet and an exhaust gas outlet, a reaction chamber gas inlet is provided on the side wall at one end of the water-gas shift reaction chamber, and a reaction chamber gas outlet is provided on the lower surface of the other end of the water-gas shift reaction chamber. The reaction chamber gas inlet is connected to the external mixed gas to be separated, and the reaction chamber gas outlet is connected to the lower cover plate gas inlet through a rubber conduit.

[0012] The water-gas shift reaction chamber is an annular frame structure with a hollow interior. The first graphite gasket and the second graphite gasket are both planar frame structures. The second graphite gasket and the inner walls on both sides of the water-gas shift reaction chamber are provided with slots for placing support blocks. The water-gas shift reaction chamber, the first metal copper mesh, the second metal copper mesh and the support blocks together form a cubic chamber, and the cubic chamber is filled with solid granular water-gas shift reaction catalyst; the first graphite gasket between the upper cover plate and the first palladium-copper alloy membrane, the upper cover plate, and the first palladium-copper alloy membrane together form a permeation chamber, and the first graphite gasket between the second palladium-copper alloy membrane and the lower cover plate, and the second palladium-copper alloy membrane and the lower cover plate together form a secondary permeation chamber.

[0013] The upper cover plate, the first graphite gasket, the first palladium-copper alloy membrane, the first metal copper mesh, the second graphite gasket, the water-gas shift reaction chamber, the second metal copper mesh, the second palladium-copper alloy membrane and the lower cover plate are all provided with bolt fixing holes at the same position on the periphery, and the bolt fixing holes are used to pass fixing bolts.

[0014] The thickness of the first metal copper mesh and the second metal copper mesh are both 1-2 mm, and the inner circles of the first metal copper mesh and the second metal copper mesh are both provided with a plurality of inner circle round through holes with a diameter of 2 mm, and the hole spacing between two adjacent inner circle round through holes is 5 mm.

[0015] The support block is provided with a plurality of ventilation holes with a diameter of 3 mm, the hole spacing between two adjacent ventilation holes is 9 mm, and the height of the support block is equal to the spacing between the lower surface of the first metal copper mesh and the upper surface of the second metal copper mesh.

[0016] The mass fraction of palladium element in the first palladium-copper alloy membrane and the second palladium-copper alloy membrane is 50% to 60%, the mass fraction of copper element is 40% to 50%, the film thickness of the first palladium-copper alloy membrane and the second palladium-copper alloy membrane is 20 to 40 μm, and the substrate in the palladium-copper alloy membrane is a porous ceramic sheet.

[0017] The present invention is a stacked hydrogen purification membrane reactor for purifying H2 in a product of methanol steam reforming. The present invention fills a water-gas shift reaction chamber with a spherical water-gas shift reaction catalyst, converts CO in an introduced mixed gas into H2, and simultaneously uses a palladium-copper alloy membrane to separate H2, and recovers residual H2 after the first gas separation through a secondary permeation chamber, thereby removing CO while reducing H2 waste and increasing H2 production. By utilizing the characteristics of a high degree of modularization and a low expansion cost of the stacked reactor, the membrane reactor structure can be freely expanded according to the working conditions, effectively improving the purity of H2, and having a wide range of uses.

[0018] The beneficial effects of the present invention are:

[0019] 1) Increase the yield of H2 in the methanol steam reforming product and remove CO. The methanol steam reforming product contains a certain amount of CO, and the water-gas shift reaction can convert CO into H2. Since H2, as a product of the water-gas shift reaction, is continuously separated by the membrane into the permeation chamber, the water-gas shift reaction will continue to proceed in the direction of producing H2, which can remove most of the CO and increase the amount of H2. The mixed gas after the first gas separation will enter the secondary permeation chamber, and the residual H2 in the mixed gas can re-enter the water-gas shift reaction chamber through the secondary permeation chamber for recovery, which can reduce the waste of H2 and increase the yield.

[0020] 2) Improve the purity of H2 in the product of methanol steam reforming and avoid the "hydrogen embrittlement" problem of palladium alloy membranes. The product of methanol steam reforming will be separated by a palladium-copper alloy membrane. Although the separation effect of the palladium-copper alloy membrane is not as good as that of a pure palladium membrane, high-purity H2 can still be obtained after separation. If the purity of H2 after one separation does not meet the requirements, or the CO content in the collected H2 is too high, multiple layers of palladium-copper alloy membranes and multiple water-gas shift reaction chambers can be stacked to obtain extremely high-purity H2. At the same time, the palladium-copper alloy membrane can operate in a large temperature range, effectively avoiding the "hydrogen embrittlement" problem of the palladium alloy membrane and extending the service life of the membrane reactor.

[0021] 3) The stacked membrane reactor has a high degree of modularity and low cost. The membrane reactor structure can be freely expanded according to the working conditions and has a wide range of applications. During the expansion of the tubular membrane reactor, the increase in the diameter of the pipe will cause the outer structure volume and membrane surface area to increase significantly, and the cost will increase significantly. The stacked membrane reactor only needs to be expanded in the vertical direction, and each layer of the structure in the reactor remains unchanged. The specified layers can be set as a module and stacked multiple times, so the modularity is higher, the cost is lower, and the expansion is simpler. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a working principle diagram of the present invention.

[0023] Figure 2 It is a three-dimensional exploded schematic diagram of the present invention.

[0024] Figure 3 It is an assembly diagram of the water-gas shift reaction chamber of the present invention.

[0025] Figure 4 It is an isometric view of the lower cover plate of the present invention.

[0026] Figure 5 It is a schematic diagram of a single module of the present invention.

[0027] Figure 6 It is a multi-modular schematic diagram of the present invention.

[0028] Figure 7 It is an isometric view of the overall device of the present invention.

[0029] In the figure: 1. upper cover plate; 2. first graphite gasket; 3. first palladium-copper alloy membrane; 4. first metal copper mesh; 5. second graphite gasket; 6. water-gas shift reaction chamber; 7. second metal copper mesh; 8. second palladium-copper alloy membrane; 9. lower cover plate; 10. rubber conduit; 11. reaction chamber gas inlet; 12. support block; 13. reaction chamber gas outlet; 14. lower cover plate gas inlet; 15. exhaust gas outlet; 16. rectangular frame. DETAILED DESCRIPTION

[0030] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0031] like Figure 2 As shown, it is mainly composed of an upper cover plate 1, a first graphite gasket 2, a first palladium-copper alloy film 3, a first graphite gasket 2, a first metal copper mesh 4, a second graphite gasket 5, a water-gas shift reaction chamber 6, a second graphite gasket 5, a second metal copper mesh 7, a first graphite gasket 2, a second palladium-copper alloy film 8, a first graphite gasket 2 and a lower cover plate 9, which are stacked in sequence from top to bottom using bolts;

[0032] The membrane reactor separates carbon monoxide (CO) and hydrogen (H2) in the harmful mixed gas through the first palladium-copper alloy membrane 3 and the second palladium-copper alloy membrane 8, and converts carbon monoxide into hydrogen, thereby increasing the hydrogen production while removing carbon monoxide from the mixed gas, thereby achieving the purification and utilization of hydrogen.

[0033] like Figure 3 and 4 As shown in the figure, an outlet for an external vacuum pump is provided in the upper cover plate 1, and the vacuum pump is used to extract the purified hydrogen, and the internal pressure of the permeation chamber is controlled to be 90 kPa by the vacuum pump. A lower cover plate gas inlet 14 and a tail gas outlet 15 are provided in the lower cover plate 9, and the tail gas outlet 15 is used to discharge other gases in the mixed gas except H2. A reaction chamber gas inlet 11 is provided on the side wall at one end of the water-gas shift reaction chamber 6, and a reaction chamber gas outlet 13 is provided on the lower surface of the other end of the water-gas shift reaction chamber 6. The reaction chamber gas inlet 11 is connected to the harmful mixed gas from the outside, and the reaction chamber gas outlet 13 is connected to the lower cover plate gas inlet 14 through a rubber conduit 10, and the joints are all glued.

[0034] The water-gas shift reaction chamber 6 is an annular frame structure with a hollow interior. The first graphite gasket 2 and the second graphite gasket 5 are both planar frame structures. The inner side walls on both sides of the second graphite gasket 5 and the water-gas shift reaction chamber 6 are provided with slots for placing support blocks 12. The support blocks 12 are embedded in the slots of the second graphite gasket 5 and the water-gas shift reaction chamber 6, so that the two second graphite gaskets 5 are connected to the water-gas shift reaction chamber 6 through the support blocks 12. The second graphite gasket 5 and the first metal copper mesh 4 are sequentially installed on the upper side of the water-gas shift reaction chamber 6 from bottom to top, and the second graphite gasket 5 and the second metal copper mesh 7 are sequentially installed on the lower side of the water-gas shift reaction chamber 6 from top to bottom. The water-gas shift reaction chamber 6, the first metal copper mesh 4, the second metal copper mesh 7 and the support blocks 12 together enclose a closed cubic chamber, and the cubic chamber is filled with solid granular water-gas shift reaction catalyst;

[0035] The first graphite gasket 2 between the upper cover plate 1 and the first palladium-copper alloy membrane 3 and the upper cover plate 1 and the first palladium-copper alloy membrane 3 together form a permeation cavity, and the first graphite gasket 2 between the second palladium-copper alloy membrane 8 and the lower cover plate 9 and the second palladium-copper alloy membrane 8 and the lower cover plate 9 together form a secondary permeation cavity. The permeation cavity is used to collect hydrogen, and the secondary permeation cavity is used to filter exhaust gas.

[0036] like Figure 7As shown, the upper cover plate 1, the first graphite gasket 2, the first palladium-copper alloy membrane 3, the first metal copper mesh 4, the second graphite gasket 5, the water-gas shift reaction chamber 6, the second metal copper mesh 7, the second palladium-copper alloy membrane 8 and the lower cover plate 9 are all provided with bolt fixing holes for inserting bolts at the same position on the periphery, the graphite gaskets 2 and 5 are both used for sealing, and the membrane reactor as a whole is fastened by bolts.

[0037] The thickness of the first metal copper mesh 4 and the second metal copper mesh 7 are both 1-2 mm. In a specific implementation, the outer circles of the first metal copper mesh 4 and the second metal copper mesh 7 are each provided with a plurality of bolt fixing holes with a diameter of 6.5 mm, and the inner circles of the first metal copper mesh 4 and the second metal copper mesh 7 are each provided with a plurality of inner circle circular through holes with a diameter of 2 mm, and the hole spacing between two adjacent inner circle circular through holes is 5 mm, the bolt fixing holes are used for bolt and nut connection, and the inner circle circular through holes are used to limit the passage of water-gas shift reaction catalyst particles and only allow gas to pass through.

[0038] A plurality of ventilation holes with a diameter of 3 mm are provided in the support block 12. The hole spacing between two adjacent ventilation holes is 9 mm. The ventilation holes are used to limit the passage of catalyst particles of the water-gas shift reaction and only allow gas to pass through. The height of the support block 12 is equal to the spacing between the lower surface of the first metal copper mesh 4 and the upper surface of the second metal copper mesh 7.

[0039] The mass fraction of palladium element in the first palladium-copper alloy membrane 3 and the second palladium-copper alloy membrane 8 is 50% to 60%, and the mass fraction of copper element is 40% to 50%. The film thickness of the first palladium-copper alloy membrane 3 and the second palladium-copper alloy membrane 8 is 20 to 40 μm. The substrate in the palladium-copper alloy membrane 3 adopts a porous ceramic sheet, and the mechanical strength of the palladium-copper alloy membranes 3 and 8 is improved by the porous ceramic substrate.

[0040] like Figure 5 and Figure 6 As shown, the membrane reactor can also be stacked and expanded by multiple modules to form a multi-module membrane reactor, which is suitable for various working conditions and purity requirements, and the structures of each module are the same. A single module includes a first palladium-copper alloy membrane 3, a first graphite gasket 2, a first metal copper mesh 4, a second graphite gasket 5, a rectangular frame 16, a second graphite gasket 5, a second metal copper mesh 7 and a first graphite gasket 2 from top to bottom. The first metal copper mesh 4, the second graphite gasket 5, the rectangular frame 16, the second graphite gasket 5 and the second metal copper mesh 7 in a single module together constitute a closed cubic chamber, and the cubic chamber is filled with a water-gas shift reaction catalyst.

[0041] The specific form of the multi-module membrane reactor stacked in sequence from top to bottom in the vertical direction is: an upper cover plate 1, a first graphite gasket 2, several modules, a first palladium-copper alloy membrane 3, a first graphite gasket 2, a first metal copper mesh 4, a second graphite gasket 5, a water-gas shift reaction chamber 6, a second graphite gasket 5, a second metal copper mesh 7, a first graphite gasket 2, several modules, a second palladium-copper alloy membrane 8, a first graphite gasket 2 and a lower cover plate 9.

[0042] like Figure 1 As shown, the methanol steam reforming product is first introduced into the water-containing gas cylinder, and the humidified mixed gas is then introduced into the water-gas shift reaction chamber 6 through the reaction chamber gas inlet 11. Since the vacuum pump controls the pressure of the permeation chamber at 80 kPa, which is lower than the pressure in the water-gas shift reaction chamber, the permeation pressure is formed inside and outside the first palladium-copper alloy membrane 3, and the density of H2 in the mixed gas is relatively low. Therefore, after H2 enters the water-gas shift reaction chamber 6, it moves upward and permeates through the first palladium-copper alloy membrane 3 on the upper side into the permeation chamber, and H2 is sucked out and collected by the vacuum pump. CO and H2O in the mixed gas react on the surface of the water-gas shift reaction catalyst to generate CO2 and H2. This part of the generated H2 will also permeate upward into the permeation chamber and be sucked out and collected by the vacuum pump; H2 is continuously separated as a reaction product, which promotes the water-gas shift reaction to proceed in the direction of generating H2, so CO can be basically removed by the water-gas shift reaction. The surface of the first palladium-copper alloy membrane 3 has limited hydrogen adsorption sites. When the gas flow rate entering the water-gas shift reaction chamber 6 is large, some H2 will not have time to penetrate through the first palladium-copper alloy membrane 3 on the upper side. These residual H2 will flow out from the reaction chamber gas outlet 13 on the right side of the water-gas shift reaction chamber 6 along with other gases, and enter the secondary permeation chamber through the rubber conduit 10. Due to the gas inertia and the lower density of H2, the residual H2 will continue to move upward after entering the secondary permeation chamber, permeate through the second palladium-copper alloy membrane 8 on the lower side and return to the water-gas shift reaction chamber 6, and continue to move upward through the first palladium-copper alloy membrane 3 on the upper side to enter the permeation chamber and be sucked out and collected by the vacuum pump. The H2 that cannot be collected will circulate along the above-mentioned gas passage until it all enters the permeation chamber and is sucked out and collected. Other gases that cannot pass through the palladium-copper alloy membranes 3 and 8 are collectively referred to as exhaust gas and are discharged from the tail gas outlet 15.

[0043] The methanol steam reforming product is moistened by the water cylinder and enters the water-gas shift reaction chamber 6 through the reaction chamber gas inlet 11 of the water-gas shift reaction chamber 6. The gas that cannot permeate through the first palladium-copper alloy membrane 3 enters the rubber conduit 10 through the reaction chamber gas outlet 13, and finally enters the secondary permeation chamber through the lower cover plate gas inlet 14, wherein the residual H2 enters the permeation chamber and continues to permeate upward through the second palladium-copper alloy membrane 8, while the gas that cannot permeate through the second palladium-copper alloy membrane 8 is discharged from the tail gas outlet 15.

[0044] The working principle of the present invention is as follows:

[0045] First, the gas outlet of the upper cover plate 1 is connected to an external vacuum pump, and the vacuum pump is turned on. The vacuum pump controls the pressure of the permeation chamber at 80 kPa, which is lower than the pressure in the water-gas shift reaction chamber 6, so that an osmotic pressure is formed inside and outside the first palladium-copper alloy membrane 3. Secondly, the methanol steam reforming product is passed into the water gas cylinder, and the humidified mixed gas enters the water-gas shift reaction chamber 6 through the reaction chamber gas inlet 11. Due to the low density of H2 in the mixed gas and the influence of the osmotic pressure, H2 enters the water-gas shift reaction chamber 6 and moves upward, passes through the first metal copper mesh 4 and permeates through the first palladium-copper alloy membrane 3 to enter the permeation chamber, and is finally sucked out and collected by the vacuum pump. After the CO and H2O in the mixed gas enter the water-gas shift reaction chamber 6, they react on the surface of the water-gas shift reaction catalyst to generate CO2 and H2. This part of the generated H2 will also pass upward through the first metal copper mesh 4 and permeate through the first palladium-copper alloy membrane 3 into the permeation chamber, and finally be sucked out and collected by the vacuum pump; at the same time, H2 is continuously separated as a product of the water-gas shift reaction, which promotes the water-gas shift reaction to proceed in the direction of generating H2, so CO can be basically removed through the water-gas shift reaction.

[0046] Due to the limited hydrogen adsorption sites on the surface of the palladium-copper alloy membrane, when the gas flow rate entering the water-gas shift reaction chamber is large, some H2 in the mixed gas will not have time to penetrate through the first palladium-copper alloy membrane 3. These residual H2 will enter the rubber conduit 10 from the reaction chamber gas outlet 13 with other gases, and finally enter the secondary permeation chamber through the lower cover plate gas inlet 14. Due to the gas inertia and the lower density of H2, the residual H2 will continue to move upward after entering the secondary permeation chamber, permeate through the second palladium-copper alloy membrane 8 and pass through the second metal copper mesh 7, and return to the water-gas shift reaction chamber 6. At this time, the residual H2 is affected by the osmotic pressure and density, and continues to move upward through the first metal copper mesh 4 and the first palladium-copper alloy membrane 3 into the permeation chamber, and is finally sucked out and collected by the vacuum pump. The H2 that cannot be collected will circulate along the above-mentioned gas passage until it all enters the permeation chamber and is sucked out and collected. The gases that cannot pass through the first palladium-copper alloy membrane 3 and the second palladium-copper alloy membrane 8 are collectively referred to as exhaust gas, which is discharged from the tail gas outlet 15.

[0047] The membrane reactor of the present invention mainly involves the water-gas shift reaction: CO+H2O→CO2+H2

[0048] The temperature of the water gas shift reaction is generally 180-250° C., and the temperature of the methanol steam reforming reaction is generally 250-300° C. Therefore, the methanol steam reforming product can be directly introduced into the water gas shift reaction chamber 6 for reaction after passing through the water gas cylinder, without the need for additional heating.

[0049] Considering that when the flow rate of methanol steam reforming gas is large or the CO content is high, the CO in the mixed gas cannot be completely removed by a water-gas shift reaction; at the same time, although very high-purity H2 can be obtained through the palladium-copper alloy membranes 3 and 8, a small part of impurities will still penetrate through the first palladium-copper alloy membrane 3 and be collected. The CO in this part of impurities is fatal to the proton membrane fuel cell. Therefore, when the gas flow rate is large or the CO content is high, problems such as failure to obtain high-purity H2, H2 waste, and inability to completely remove CO will occur. Therefore, the membrane reactor of the present invention is modularly designed for the structure, and multiple water-gas shift reactions and multiple membrane separations are realized by superposition of multiple modules. CO is removed and the yield of H2 is increased by multiple water-gas shift reactions, and the content of impurities is reduced by multiple membrane separations to increase the purity of H2.

[0050] The stacked membrane reactor of the present invention can be freely expanded according to demand, is applicable to a variety of working conditions, and only needs to stack and expand the modules in the vertical direction, and the structure of each module remains unchanged, and is fastened by bolts after the stacking is completed. The expansion of other membrane reactors will lead to a significant increase in the volume of the outer structure and the surface area of ​​the membrane, and the cost will also increase significantly. Therefore, the stacked purification membrane reactor of the present invention has a higher degree of modularization, and can obtain better purification performance at a lower cost and a simpler method.

[0051] The above specific implementation modes are used to explain the present invention rather than to limit the present invention. Within the spirit of the present invention and the protection scope of the claims, that is, equivalent changes and modifications made according to the protection scope of the present invention and the contents of the specification should fall within the protection scope of the present invention.

Claims

1. A stacked hydrogen purification membrane reactor, characterized in that: The invention mainly comprises an upper cover plate (1), a first graphite gasket (2), a first palladium-copper alloy film (3), a first graphite gasket (2), a first metal copper mesh (4), a second graphite gasket (5), a water-gas shift reaction chamber (6), a second graphite gasket (5), a second metal copper mesh (7), a first graphite gasket (2), a second palladium-copper alloy film (8), a first graphite gasket (2) and a lower cover plate (9), which are stacked in sequence from top to bottom; The membrane reactor separates carbon monoxide and hydrogen in the mixed gas through the first palladium-copper alloy membrane (3) and the second palladium-copper alloy membrane (8), and converts carbon monoxide into hydrogen, thereby increasing the hydrogen production while removing carbon monoxide from the mixed gas, thereby achieving purification and utilization of hydrogen; The upper cover plate (1) is provided with an outlet for connecting to an external vacuum pump, the lower cover plate (9) is provided with a lower cover plate gas inlet (14) and an exhaust gas outlet (15), a reaction chamber gas inlet (11) is provided on the side wall at one end of the water-gas shift reaction chamber (6), and a reaction chamber gas outlet (13) is provided on the lower surface at the other end of the water-gas shift reaction chamber (6), the reaction chamber gas inlet (11) is connected to the external mixed gas to be separated, and the reaction chamber gas outlet (13) is connected to the lower cover plate gas inlet (14) through a rubber conduit (10).

2. A stacked hydrogen purification membrane reactor according to claim 1, characterized in that: The water-gas shift reaction chamber (6) is an annular frame structure with a hollow interior. The first graphite gasket (2) and the second graphite gasket (5) are both planar frame structures. The inner side walls of the second graphite gasket (5) and the water-gas shift reaction chamber (6) are both provided with slots for placing support blocks (12). The water-gas shift reaction chamber (6), the first metal copper mesh (4), the second metal copper mesh (7) and the support blocks (12) together form a cubic chamber, and the cubic chamber is filled with solid granular water-gas shift reaction catalyst. The first graphite gasket (2) between the upper cover plate (1) and the first palladium-copper alloy membrane (3) and the upper cover plate (1) and the first palladium-copper alloy membrane (3) together form a permeation chamber, and the first graphite gasket (2) between the second palladium-copper alloy membrane (8) and the lower cover plate (9) and the second palladium-copper alloy membrane (8) and the lower cover plate (9) together form a secondary permeation chamber.

3. A stacked hydrogen purification membrane reactor according to claim 1, characterized in that: The upper cover plate (1), the first graphite gasket (2), the first palladium-copper alloy membrane (3), the first metal copper mesh (4), the second graphite gasket (5), the water-gas shift reaction chamber (6), the second metal copper mesh (7), the second palladium-copper alloy membrane (8) and the lower cover plate (9) are all provided with bolt fixing holes at the same position on the periphery, and the bolt fixing holes are used to insert fixing bolts.

4. The stacked hydrogen purification membrane reactor according to claim 1, characterized in that: The thickness of the first metal copper mesh (4) and the second metal copper mesh (7) are both 1 to 2 mm, and the inner circles of the first metal copper mesh (4) and the second metal copper mesh (7) are both provided with a plurality of inner circle circular through holes with a diameter of 2 mm, and the hole spacing between two adjacent inner circle circular through holes is 5 mm.

5. A stacked hydrogen purification membrane reactor according to claim 2, characterized in that: The support block (12) is provided with a plurality of ventilation holes with a diameter of 3 mm, the hole spacing between two adjacent ventilation holes is 9 mm, and the height of the support block (12) is equal to the spacing between the lower surface of the first metal copper mesh (4) and the upper surface of the second metal copper mesh (7).

6. The stacked hydrogen purification membrane reactor according to claim 1, characterized in that: The mass fraction of the palladium element in the first palladium-copper alloy film (3) and the second palladium-copper alloy film (8) is 50% to 60%, and the mass fraction of the copper element is 40% to 50%. The film thickness of the first palladium-copper alloy film (3) and the second palladium-copper alloy film (8) is 20 to 40 μm. The substrate in the palladium-copper alloy film (3) is a porous ceramic sheet.

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