Power supply structure of flat plate type conductive structured catalyst

Abstract

The invention discloses a power supply structure of a flat plate type conductive structured catalyst, and belongs to the technical field of chemical engineering. For the problem of local overheating caused by non-uniform current distribution of a large-area catalyst, uniform distribution is realized through geometric constraint: arranging a conductor connecting piece which is in full contact with a current lead-in / lead-out edge of the catalyst, and limiting projection coordinates of a wire connecting area to meet the conditions that a is less than or equal to 0, and b is greater than or equal to W. According to the design, the total resistance of all conductive paths is equal, and forced current is uniformly distributed in a catalyst plane. The conductor connecting piece can be located at any spatial position outside a catalyst plane, supports connection modes such as welding and crimping, and is suitable for a flat plate type structured catalyst. Local hot spots are eliminated, the service life of the catalyst is prolonged, the reaction efficiency is improved, and the method is especially suitable for large series piles.

Description

Technical Field

[0001] This invention belongs to the field of chemical technology, and specifically relates to a power supply structure for a planar conductive structured catalyst. Background Technology

[0002] "Internal resistance heating" structured catalyst reaction technology is an emerging electro-driven reaction technology in recent years. It uses a structured catalyst with a conductive framework as a resistance heating element connected to a circuit. The Joule heat generated by the current flowing through the framework heats the catalytic reaction. This technology utilizes the internal electrothermal energy of the catalyst to control the reaction temperature while retaining the enhanced mass and heat transfer characteristics of the structured catalyst, making temperature management of the catalyst bed more efficient, rapid, and flexible.

[0003] High-porosity conductive materials with various structural forms, such as metal foam, carbon fiber felt, and metal mesh, are suitable as conductive framework supports for the preparation of structured catalysts used in "resistive internal heating" applications. From a mass transfer perspective, their high porosity significantly reduces the flow resistance of the reaction system, allowing reactants to penetrate more smoothly to the catalyst's active sites, thus significantly improving mass transfer efficiency. From an electrothermal performance perspective, the high porosity of these materials provides structural resistance, resulting in high electrothermal conversion efficiency. From the perspective of catalytic active component loading, these materials have a large specific surface area, providing numerous loading sites for catalytic active components. From a practical performance perspective, these materials have high mechanical strength and good temperature resistance, adapting to pressure fluctuations and high-temperature environments in the reaction system. Furthermore, these high-porosity conductive materials can be mass-produced and processed, especially in the form of large-area flat or sheet products. These characteristics make high-porosity conductive materials promising for application in "resistive internal heating" structured catalyst reaction technology.

[0004] The industrialization of "resistive internal heating" structured catalyst reaction technology requires solving a key problem: how to achieve uniform current distribution within the conductive cross-section of large-scale structured catalysts. First, the uniformity of current distribution directly determines the temperature uniformity of the catalyst bed. According to Joule's law, heat generation is proportional to the square of the current density. If the current is unevenly distributed within a large cross-section, localized "hot spots" or "cold spots" will form, leading to problems such as sintering of active components and decreased selectivity of target products. Second, uneven current distribution results in waste. If the reaction bed is locally overheated, excess heat will be lost as waste heat, wasting energy; areas with sparse current will struggle to reach the optimal reaction temperature, leading to waste of catalyst and reactants. Third, uneven current distribution may pose safety risks. High temperatures at points of current concentration may cause phase transformation in the framework material, reducing its mechanical strength and potentially causing bed structure collapse, resulting in production safety accidents.

[0005] Achieving uniform current distribution across the conductive cross-section of large-scale structured catalysts presents multi-dimensional technical challenges. Besides ensuring the uniformity of conductivity and contact resistance between electrodes and catalysts at the industrial manufacturing level, the scientific design of the power supply structure for large-scale structured catalyst beds is also crucial, requiring comprehensive consideration of the following factors: First, it is necessary to guide current uniformly from narrow-section wires into the wide-section catalyst within a limited space. External power is typically supplied to the reactor via narrow-section, high-conductivity wires / cables. Efficiently achieving uniform current diffusion from narrow-section conductors to wide-section catalysts within the limited space of the reactor is a critical issue. Second, minimizing the number of electrical interfaces is essential. Supplying power to the high-temperature, high-pressure reactor necessitates current inlet / outlet interfaces on the reactor walls, leading to insulation and sealing issues. Reducing the number of interfaces improves reactor safety and lowers manufacturing costs. Third, minimizing the wiring layout within the reactor is also vital. Simplified wiring not only reduces safety risks such as short circuits, open circuits, and partial discharges caused by poor contact, but also reduces maintenance difficulty and improves reactor operational safety and reliability.

[0006] Although planar high-porosity structured catalysts such as metal foam, carbon fiber felt, and metal mesh have been used in "resistive internal heating" structured catalyst reaction technology, the aforementioned problems have not yet received sufficient attention. The reported power supply structures are relatively simple, making it difficult to achieve uniform current distribution in large-area planar structured catalysts. For example, Chinese patent CN119793342A supplies power to the metal foam catalyst using stainless steel alligator clips; Chinese patent CN120079393A supplies power to the metal foam catalyst by tightly pressing two copper electrodes; and Chinese patent CN120243034A uses a power supply structure where conductive carbon fibers are directly connected to the metal foam catalyst. Summary of the Invention

[0007] The purpose of this invention is to provide a power supply structure for a planar conductive structured catalyst to facilitate uniform "internal resistance heating".

[0008] The basic idea of ​​this invention is as follows:

[0009] To achieve uniform current distribution on the surface of a large-area planar structured catalyst when connected to a circuit via a wire, the key lies in ensuring the total resistance (Rt) of all parallel conductive paths within the catalyst plane. total The basic idea is as follows:

[0010] First, it is necessary to design a planar catalyst with a rectangular or square conductive heating region. When its pair of parallel sides are used as the current input and output sides, all conductive paths perpendicular to these sides have exactly equal lengths. For catalysts with uniform material and thickness, their internal resistance (R1) is proportional to the path length. Therefore, the internal resistance (R1) of all parallel conductive paths is naturally equal, providing a geometric basis for achieving equal total resistance.

[0011] Secondly, balancing the resistance of the external path is crucial. From a circuit analysis perspective, the total resistance of any path from the current injection point to the current output point can be decomposed into three parts:

[0012] (1) The path resistance (R2) of the catalyst from the current injection point to a point P1 on its current input side.

[0013] (2) The path resistance (R1) inside the catalyst from the current input point P1 to the current output point P2.

[0014] (3) The path resistance (R3) from the current output point P2 to the current output point outside the catalyst.

[0015] Under the aforementioned conditions, R1 is constant, thus achieving R... total The key to ensuring equality translates to ensuring that the external resistances (R2+R3) of all paths are also equal.

[0016] Furthermore, to ensure a constant external resistance (R2+R3), the positions of the current injection / extraction points need to be controlled. For (R2+R3) to be constant, the spatial positions of the current injection and extraction points must satisfy specific conditions: a one-dimensional coordinate system (0 to W) is established with the current input edge as the reference; the projection coordinates a of the reference point of the current injection point on this coordinate system are ≤0; the projection coordinates b of the reference point of the current extraction point are ≥W. The reference point mentioned in this invention refers to the current input / output position reference used for projection positioning. When the connection area is a point-like structure (such as a solder joint), the reference point is the point itself; when it is a surface-like structure (such as a bolt hole), the reference point is its geometric or electrical center point, and its projection coordinates should satisfy the conditions a≤0 and b≥W. This condition ensures that for any parallel conductive path P1P2 within a conductive heating area, the total length of its external path |P1-a|+|P2-b| is always a constant (ba). Under the condition of uniform conductor resistivity, this means that the external resistance (R2+R3) is constant and independent of the position selection of P1 and P2.

[0017] This keeps both the internal resistance (R1) and the external resistance (R2+R3) constant, meaning the total resistance (R) of all parallel conductive paths remains constant. total The current will be equal to the current in the conductive region of the planar catalyst, according to Ohm's law.

[0018] This method is based on the geometry of the electrothermal region, and then constrains the external resistance by precisely controlling the spatial position of the wire connection points, ultimately ensuring the uniformity of current distribution at the circuit topology level. This principle is universal, and its effectiveness is unaffected by whether the wire connection points and the catalyst are coplanar.

[0019] Based on the above ideas, the technical solution adopted by the present invention is as follows:

[0020] A power supply structure for a planar conductive structured catalyst includes:

[0021] A planar conductive structured catalyst having a rectangular or square effective conductive and heating region with oppositely arranged current-introducing and current-outtroducing edges;

[0022] The first conductor connector forms continuous electrical contact with the entire length of the current-carrying edge and has a first connection area for connecting the conductor.

[0023] The second conductor connector forms continuous electrical contact with the entire length of the current-leading edge and has a second connection area for connecting the conductor.

[0024] The first conductor connector is configured to enable current to be transmitted between the first connection region and the current-introducing edge, and to maintain a uniform distribution of current over the entire length of the current-introducing edge.

[0025] The second conductor connector is configured to enable current to be transmitted between the second connection region and the current-leading edge, and to maintain a uniform distribution of current over the entire length of the current-leading edge.

[0026] There is no electrical connection path between the first conductor connector and the second conductor connector other than the catalyst;

[0027] In this system, a one-dimensional coordinate system is established with one end of the current-introducing edge as the origin O and along its extension direction, and the coordinates of the other end are W.

[0028] The projection coordinates of the reference point of the first connecting region on the one-dimensional coordinate system are a≤0;

[0029] The projection coordinates of the reference point of the second connecting region on the one-dimensional coordinate system are b≥W.

[0030] Preferably, the current-introducing edge and the current-outtroducing edge are two parallel physical sides of the planar conductive structured catalyst.

[0031] Preferably, the projected coordinate a < 0, and / or the projected coordinate b > W.

[0032] Furthermore, the planar conductive structured catalyst includes a conductive substrate and a catalytically active component supported on the surface of the substrate. The morphology and structure of the conductive substrate include, but are not limited to, at least one of foam, fiber felt, and wire mesh.

[0033] Furthermore, the electrical connection is electrically connected to the catalyst by welding, crimping, riveting, plugging, bolting, or conductive adhesive bonding. Before the electrical contact operation, the edges of the catalyst are treated with conductive filling to reduce contact resistance.

[0034] Preferably, the electrical connection portion is provided with a groove for fixing the side of the catalyst.

[0035] Furthermore, the first connection area and / or the second connection area are weld points, rivet points, crimp points, bolt connection points, plug holes, or conductive adhesive points.

[0036] Furthermore, the first conductor connector and the second conductor connector are made of metallic materials, and their electrical conductivity is higher than that of the planar conductive structured catalyst.

[0037] Preferably, the metallic material is copper, silver, gold, aluminum, nickel, or an alloy thereof.

[0038] Furthermore, the power supply structure is suitable for series-connected fuel cells, and each catalyst unit independently satisfies the projection coordinate rule: a≤0, b≥W.

[0039] The technical solution of the present invention has the following advantages:

[0040] (1) Based on topology and circuit theory, this invention designs a geometric position principle in which the current inlet and outlet points are located outside the side, so that the total resistance of all parallel conductive paths on the plate catalyst is equal, thereby achieving uniform current distribution. The principle is fundamental and the effect is highly certain.

[0041] (2) The present invention adopts the strategy of “forcing the internal uniform distribution by precisely controlling the external boundary conditions”, that is, by controlling the two points of the source (current injection point and current output point), the problem of uniform current distribution in a two-dimensional plane is solved. The method is simple and effective.

[0042] (3) The electrical connection points in this invention can be arranged in any spatial position outside, above, below or on the side of the catalyst plane, which provides great flexibility for the mechanical structure design, heat dissipation management and pipeline layout of the reactor.

[0043] (4) The present invention can be recursively applied to each catalyst unit, which is naturally suitable for building large-scale series stacks and can ensure the performance consistency of each unit in the stack.

[0044] (5) The present invention has strong robustness and good anti-interference ability. It can tolerate certain manufacturing and assembly tolerances (such as slight deviations in the installation angle of conductor connectors). The system performance will not deteriorate sharply due to slight dimensional deviations, thus improving the yield and reliability of the product.

[0045] (6) The present invention avoids current congestion and local overheating from the circuit design level, which helps to eliminate local hot spots on the catalyst and improve long-term stability, and also helps to maximize the utilization rate of the catalyst. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention;

[0047] Figure 2 This is a schematic diagram (top view) of the structure of Embodiment 1 of the present invention.

[0048] Figure 3 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0049] Figure 4 This is a schematic diagram (top view) of the structure of Embodiment 3 of the present invention.

[0050] Figure 5 This is a schematic diagram of the structure of Embodiment 4 of the present invention.

[0051] Wherein: 1 is a planar conductive structured catalyst, 21 is a first conductor connector, 22 is a second conductor connector, 211 is a first connection region, and 222 is a second connection region. Detailed Implementation

[0052] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. However, the following embodiments are only for explaining the present invention, and the scope of protection of the present invention should include all the contents of the claims. Moreover, through the description of the following embodiments, those skilled in the art can fully implement all the contents of the claims of the present invention.

[0053] This invention relates to a power supply structure for a planar conductive structured catalyst. Its core lies in controlling the spatial position of the current injection point and the current output point to ensure that the current is uniformly distributed on the main plane of the planar structured catalyst, thereby eliminating local hot spots and improving reaction efficiency and catalyst life.

[0054] Example 1

[0055] This embodiment demonstrates a very basic application unit.

[0056] See Figure 1The planar conductive structured catalyst 1 is made of nickel foam as a framework carrier, and its main plane is rectangular with dimensions of 500mm × 200mm × 5mm. Its two 200mm sides serve as parallel current induction and current outduction sides.

[0057] Both the first conductor connector 21 and the second conductor connector 22 are made of copper and have dimensions of 230mm×20mm×10mm. They are welded together with the current-introducing side and the current-outtroducing side of the catalyst to form a strong connection along the entire length, achieving continuous electrical contact. They are also provided with wiring stud holes as the first connection area 211 and the second connection area 222 to connect external wires.

[0058] The connection point settings and projection coordinates of the conductor are as follows: Figure 2 As shown: with one end of the current-introducing edge as the origin O, a one-dimensional coordinate system is established along the edge, and the coordinate of the other end is W. The projection coordinate of the reference point of the first connecting region 211 on the one-dimensional coordinate system is a=0, and the projection coordinate of the reference point of the second connecting region 222 is b=W=200.

[0059] Example 2

[0060] This embodiment has a basically the same structure as Embodiment 1, such as... Figure 3 As shown, the difference lies in that the first conductor connector 21 and the second conductor connector 22 have grooves for fixing the side of the catalyst 1.

[0061] Example 3

[0062] This embodiment is basically the same in structure as Embodiment 1, except that the location of the connection point is set to demonstrate the flexibility of the projection rules.

[0063] Setting of wire connection points and projection coordinates (e.g.) Figure 4 ): The reference point projection coordinates of the first connection area 211 (connection stud hole) of the first conductor connector 21 are a=-8mm (a<0); the reference point projection coordinates of the second connection area 222 of the second conductor connector 22 are b=118mm (b>W).

[0064] Example 4

[0065] This embodiment illustrates the case where the current injection / extraction point is not coplanar with the catalyst principal plane.

[0066] Its structure is similar to that of Example 1, the difference being (as shown in the example). Figure 5 (as shown)

[0067] The first conductor connector 21 is a single piece of machined L-shaped nickel alloy plate, with its horizontal edge aligned with the entire current-carrying edge of the catalyst 1, and its vertical edge extending downwards towards the catalyst plane.

[0068] The first connection area 211 is located on a threaded hole on this vertically extending edge. This threaded hole is used to secure the input wire. When a coordinate system is established with the catalyst side as the reference point, the vertical projection coordinate of the reference point of this threaded hole is a = -20mm (a < 0), and its physical location is approximately 20mm below the main plane of the catalyst. Similarly, the current output point is set in a similar manner, with its projection coordinate b > W. When the connection area is a point structure (such as a weld point), its reference point is the point itself; when the connection area is a surface structure (such as a bolt hole, a socket), it is necessary to ensure that the projection coordinates of the geometric center or electrical center point satisfy the condition (a ≤ 0, b ≥ W).

[0069] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A power supply structure for a flat plate conductive structured catalyst, characterized by, The power supply structure comprises: a flat conductive structured catalyst (1) having a rectangular or square effective conductive heating area with oppositely arranged current input and output edges; a first conductor connecting piece (21) forming continuous electrical contact with the entire length of the current input edge and provided with a first connecting area (211) for connecting a wire; a second conductor connecting piece (22) forming continuous electrical contact with the entire length of the current output edge and provided with a second connecting area (222) for connecting a wire; the first conductor connecting piece (21) is configured to enable current transmission between the first connecting area (211) and the current input edge and maintain uniform distribution of current on the entire length of the current input edge; the second conductor connecting piece (22) is configured to enable current transmission between the second connecting area (222) and the current output edge and maintain uniform distribution of current on the entire length of the current output edge; there is no electrical connection path between the first conductor connecting piece (21) and the second conductor connecting piece (22) except the catalyst (1); wherein the one end of the current input edge is taken as the coordinate origin O, and a one-dimensional coordinate system is established along the extension direction of the current input edge, and the coordinate of the other end is W; the projection coordinate of the reference point of the first connecting area (211) in the one-dimensional coordinate system is a≤0; the projection coordinate of the reference point of the second connecting area (222) in the one-dimensional coordinate system is b≥W.

2. The power supply structure according to claim 1, characterized by The current input edge and the current output edge are two parallel physical side edges of the flat conductive structured catalyst (1).

3. The power supply structure according to claim 1, wherein The projection coordinate a<0 and / or the projection coordinate b>W.

4. The power supply structure according to claim 1, wherein The flat conductive structured catalyst (1) comprises a conductive substrate and a catalytically active component supported on the surface of the substrate, and the morphological structure of the conductive substrate includes but is not limited to at least one of foam, fiber felt and wire mesh.

5. The power supply structure according to claim 1, wherein The first conductor connecting piece (21) and / or the second conductor connecting piece (22) realize continuous electrical contact with the catalyst (1) by welding, crimping, riveting, plugging, bolt connection or conductive adhesive bonding, and before the electrical contact operation, the edges of the catalyst are subjected to conductive filling treatment to reduce the contact resistance.

6. The power supply structure according to claim 1, wherein The first conductor connecting piece (21) and / or the second conductor connecting piece (22) are provided with grooves for fixing the side edges of the catalyst (1).

7. The power supply structure according to claim 1, wherein The first connecting area (211) and / or the second connecting area (222) are welding points, riveting points, crimping points, bolt connection points, plugging holes or conductive bonding points.

8. The power supply structure according to claim 1, wherein the first conductor connecting piece (21) and the second conductor connecting piece (22) are made of a metal material with higher electrical conductivity than the flat conductive structured catalyst (1).

9. The power supply structure according to claim 8, wherein The metal material is copper, silver, gold, aluminum, nickel or an alloy thereof.

10. The power supply structure of claim 1, wherein: The power supply structure is suitable for a series electric pile, and each catalyst unit independently satisfies the projection coordinate rules: a≤0 and b≥W.

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