Joule hot plate type electrically driven reactor and application thereof

Abstract

The invention discloses a Joule hot plate type electrically driven reactor which comprises a plate type structure metal shell, one end of the plate type structure metal shell is provided with a gas inlet, and the other end of the plate type structure metal shell is provided with a gas outlet. A baffle, a porous gas distribution plate and an integral electric heating alloy channel assembly are sequentially arranged in the plate-type structure metal shell from the gas inlet to the gas outlet, the integral electric heating alloy channel assembly is filled with a particle catalyst, and a drainage conductor is further arranged on the outer wall of the plate-type structure metal shell. The invention also discloses an application of the Joule hot plate type electrically driven reactor in an endothermic reaction system. The integral electric heating alloy channel assembly is adopted, Joule heat is directly generated through electrification, heat is evenly distributed on the catalyst filling layer, quick response and efficient heat transfer are achieved, and the problem of heat loss in a traditional outer wall heating mode is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of reactors, and in particular relates to a Joule heat plate type electrically driven reactor and application thereof. Background Art

[0002] In the modern chemical and energy fields, highly endothermic reactions such as methane reforming and propane dehydrogenation play an important role in the production of clean energy and the preparation of high value-added chemicals. These reactions not only require a large amount of heat supply to maintain high temperature conditions, but also impose strict requirements on precise temperature control to ensure high selectivity and high conversion rate of the reaction. However, traditional reactors rely on fossil fuel combustion to provide heat. This heating method has significant technical bottlenecks and environmental problems, including low thermal efficiency, CO x High emissions, difficulty in temperature control, and high equipment complexity. Traditional reactors transfer heat through the outer wall, with significant heat loss and limited by the thermal conductivity of the wall and the loaded catalyst particles, which can easily lead to uneven heat distribution in the catalyst layer, thereby restricting the improvement of reaction efficiency. At the same time, the combustion of fossil fuels will produce a large amount of greenhouse gases such as carbon dioxide. In addition, the temperature gradient in strongly endothermic reactions may cause local overheating of the catalyst, thereby increasing side reactions and carbon deposits, shortening the catalyst life and reducing the selectivity of the target product. Traditional combustion reactors also require complex combustion chamber and refractory material designs, which not only have high initial investment, but also very expensive operating and maintenance costs.

[0003] In recent years, electric drive heating technology has gradually attracted widespread attention as a green solution to replace traditional combustion heating. Compared with traditional methods, electric drive technology realizes heat supply through direct electric heating, and has significant advantages such as precise heating, modular design, environmental friendliness and fast start-stop capability. In the prior art, plate-type electric heating reactors have been proposed as an improvement scheme. For example, CN113856571A discloses an electric heating plate reactor, which provides heat for the catalyst by embedding electric heating wires and improves the efficiency of thermal energy utilization through heat conduction. However, the design uses electric heating wires as the heating source, which has the problems of local temperature unevenness and slow thermal response speed, and the electric heating wires are easily invalidated due to long-term high temperature operation, affecting the life of the equipment. In addition, the overall structure of the reactor is complex, the manufacturing cost is high, and the maintenance and replacement of the heating elements are also inconvenient, which limits the scalability of industrial applications. Summary of the invention

[0004] The purpose of the present invention is to address the shortcomings of existing reactors in strongly endothermic reaction processes, especially the problems of uneven internal temperature distribution, low heat transfer efficiency, low heat utilization rate and complex operation of outer wall heating reactors, and to provide a high-efficiency reactor with electric drive function as the core, adopting plate-type modular design and skid-mounted integration.

[0005] To achieve the above-mentioned objectives, the first aspect of the present invention provides a Joule heat plate-type electrically driven reactor, the reactor comprising a plate-type structure metal shell, one end of the plate-type structure metal shell is provided with a gas inlet, and the other end is provided with a gas outlet, and a baffle, a porous gas distribution plate and an integral electric heating alloy channel assembly are sequentially provided from the gas inlet to the gas outlet, and the integral electric heating alloy channel assembly is filled with a granular catalyst, and a drainage conductor is also provided on the outer wall of the plate-type structure metal shell.

[0006] According to the present invention, the baffle is arranged inside the gas inlet of the plate-type metal shell, and its surface facing the gas inlet is an inclined surface inclined inwardly from the center to both sides. Preferably, the baffle is in the shape of a triangular prism.

[0007] According to the present invention, the porous gas distribution plate is arranged behind the baffle, the porous gas distribution plate is in a rectangular parallelepiped shape, and has pores evenly distributed in the horizontal direction.

[0008] Furthermore, the pore size is 4 mm, and the porosity of the porous gas distribution plate is 50%.

[0009] According to the present invention, the integral electric heating alloy channel assembly is in the shape of a cuboid, the interior of which is divided into a plurality of parallel channels, the cross-section of the channels is square, and all channels have the same wall thickness, and the number of the channels is 10 to 20.

[0010] According to the present invention, the catalyst particles are filled in the channel, and their shapes are selected from one or more combinations of spheres, cylinders, cloverleaf shapes, Raschig rings, four-hole columns, and seven-hole columns. The filling length is 450 mm, and the volume density is 0.75 g / cm 3 Support plates are installed at both the front and rear ends of the channel. The support plates adopt a porous structure to prevent the loss of catalyst particles while ensuring smooth gas flow.

[0011] According to the present invention, the material of the integral electric heating alloy channel component is FeCrAl alloy, NiCr alloy or NiCrFe alloy, and the conductor material of the drainage conductor is Fe, Cr, Ni, Al, Cu or their alloys, and its resistivity is lower than the body of the integral electric heating alloy channel component.

[0012] According to the present invention, thermal insulation cotton and insulating material are filled between the outer wall of the integral electric heating alloy channel component and the inner wall of the plate-type structural metal shell.

[0013] According to a preferred embodiment of the present invention, the length of the plate-type structural metal shell is 1000mm, the width is 500mm, the height is 50mm, and the wall thickness is 5mm; the thickness of the porous gas distribution plate is 25mm; the side length of the channel of the integral electric heating alloy channel assembly is 40mm, the length is 500mm, and the wall thickness is 5mm.

[0014] A second aspect of the present invention provides the use of the above-mentioned Joule heat plate type electrically driven reactor in an endothermic reaction system, wherein the endothermic reaction system includes methane steam reforming, dry gas reforming, mixed reforming and propane dehydrogenation.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. High-efficiency heat transfer performance: The integrated electric heating alloy channel assembly is used to directly generate Joule heat by energizing, and the heat is evenly distributed in the catalyst loading layer, achieving rapid response and high-efficiency heat transfer, avoiding the heat loss problem in the traditional outer wall heating method. In addition, the heat transfer path is shortened, further improving the energy utilization efficiency.

[0017] 2. Modular design flexibility: The reactor adopts a plate-type modular design, which can flexibly adjust the equipment scale by increasing or decreasing the number of modules to meet different needs from laboratory research to large-scale industrial production. The modular design not only reduces the cost of equipment modification and expansion, but also improves the adaptability and maintainability of the device.

[0018] 3. Green and environmentally friendly operation: The present invention replaces traditional fuel heating with electric drive technology, significantly reducing the emission of carbon dioxide and other greenhouse gases. By combining renewable energy, the present invention achieves low-carbon or even zero-carbon operation, providing a feasible path for the green transformation of modern industry.

[0019] 4. Excellent temperature control accuracy: Equipped with an intelligent temperature control system, it ensures the temperature uniformity and stability in the reactor through multi-point real-time monitoring and precise adjustment, avoiding the problem of incomplete reaction caused by temperature difference in traditional technology. The system significantly improves the reaction efficiency and product selectivity and reduces the generation of by-products.

[0020] 5. Reliability and maintenance convenience: The present invention adopts an integrated electric heating alloy channel design, eliminating the defect of the traditional electric heating wire being easily ineffective. The device has a simplified structure and uses high-durability materials, which prolongs the service life and reduces the maintenance frequency and cost, thereby significantly reducing the investment in long-term operation.

[0021] 6. Wide applicability: The present invention is applicable to a variety of strongly endothermic reactions, including propane dehydrogenation, methane steam reforming, methane combined reforming and other chemical processes. Its high efficiency heat transfer and precise temperature control performance make it have broad application prospects in the energy and chemical fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a perspective view of a Joule heat plate type electrically driven reactor of the present invention.

[0023] Figure 2 for Figure 1 Schematic diagram of the plate-structured metal shell.

[0024] Figure 3 for Figure 1 Schematic diagram of the baffle in FIG.

[0025] Figure 4 for Figure 1 Schematic diagram of the porous gas distribution plate in FIG.

[0026] Figure 5 for Figure 1 Schematic diagram of the integral electric heating alloy channel assembly.

[0027] Figure 6 for Figure 1 Schematic diagram of the integral electric heating alloy channel assembly and the Raschig ring particles filled therein. DETAILED DESCRIPTION

[0028] The present invention will be further described below by specific examples in conjunction with the accompanying drawings. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can determine the specific process conditions according to the principles and embodiments disclosed in the present invention, as well as the purposes of the relevant process flow and the common knowledge in the art. The process equipment or devices not specifically noted in the following examples all adopt conventional equipment or devices in the art.

[0029] In the description of the present application, it should be understood that if the terms "upper", "lower", "top", "bottom", "upper end", "lower end", "thickness" and the like appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0030] The present invention provides a Joule heat plate type electrically driven reactor suitable for important industrial processes such as methane steam, dry gas, mixed reforming and propane dehydrogenation.

[0031] like Figure 1 FIG. 1 is a perspective view of a Joule heat plate type electrically driven reactor according to the present invention, which comprises a Figure 2The plate-type structure metal shell 1 shown in the figure has a gas inlet 11 at one end and a gas outlet 12 at the other end. A baffle 2, a porous gas distribution plate 3 and an integral electric heating alloy channel component 4 are sequentially arranged from the gas inlet 11 to the gas outlet 12, and the integral electric heating alloy channel component 4 is filled with a granular catalyst 5 ( Figure 6 ), a drainage conductor 6 is also provided on the outer wall of the plate-type structure metal shell 1 for connecting to an external power source to supply power to the reactor.

[0032] Furthermore, the material of the plate-type structure metal shell 1 is preferably stainless steel, which has excellent corrosion resistance and high temperature strength, is suitable for high temperature reaction conditions above 750°C, and provides reliable mechanical support and sealing space for the reactor. The modular structure design of the plate-type structure metal shell 1 is convenient for stacking with other modules, and the modules can be connected by high temperature resistant metal sealing rings and silicone gaskets to ensure sealing and stability under high temperature and high pressure operations.

[0033] Combination Figure 3 As shown, the baffle 2 is arranged inside the gas inlet 11 of the plate-type structure metal shell 1, and its surface 21 facing the gas inlet 11 is an inclined surface inclined inwardly from the center to both sides, which is used to divert the gas entering the plate-type structure metal shell 1 to both sides. Preferably, the baffle 2 is a triangular prism.

[0034] The porous gas distribution plate 3 is arranged behind the baffle 2, combined with Figure 4 As shown, the porous gas distribution plate 3 is in the shape of a rectangular parallelepiped and has pores 31 evenly distributed in the horizontal direction. The pores 31 preferably have a pore diameter of 4 mm, and the porosity of the porous gas distribution plate 3 is preferably 50%. The material of the porous gas distribution plate 3 is preferably a high-temperature ceramic material with good high-temperature resistance and mechanical strength. The function of the porous gas distribution plate 3 is to evenly distribute the reaction gas to each channel 41 to avoid fluid bias problems.

[0035] The porous gas distribution plate 3 is combined with the baffle plate 2 to adjust the reaction gas flow and ensure that the gas has a uniform flow rate when entering the integral electric heating alloy channel assembly 4 .

[0036] Combination Figure 5 and Figure 6 As shown, the material of the integral electric heating alloy channel component 4 is FeCrAl alloy, NiCr alloy or NiCrFe alloy, and can be quickly heated to a maximum temperature of 1100°C after power is turned on. The integral electric heating alloy channel component 4 is a rectangular parallelepiped, and its interior is divided into a plurality of parallel channels 41, the cross-section of the channels 41 is square, and all the channels 41 have the same wall thickness; the number of the channels 41 is 10 to 20.

[0037] The particle catalyst 5 is filled in the channel 41. The shape of the catalyst particles 5 is selected from a combination of one or more of sphere, cylinder, clover, Raschig ring, four-hole column, and seven-hole column. The particle size is about 10 mm. The filling length of the particle catalyst 5 filled in the channel 41 is 450 mm, and the volume density is 0.75 g / cm 3 Support plates (not shown in the figure) are installed at both the front and rear ends of the channel 41. The support plates have a porous structure, which can prevent the loss of catalyst particles while ensuring smooth gas flow.

[0038] The conductor material of the drain conductor 6 is Fe, Cr, Ni, Al, Cu or their alloys, such as nickel-copper alloy, and its resistivity is lower than the body of the integral electric heating alloy channel assembly 4. The connection of the drain conductor 6 is provided with an insulating sealing ring, and is connected to an external power supply through an insulating sealing ring to ensure stable power supply. Preferably, in order to prevent heat loss and improve thermal efficiency, the outer wall of the integral electric heating alloy channel assembly 4 and the inner wall of the plate-type structure metal shell 1 are filled with insulation cotton and insulating material (not shown in the figure). The insulation cotton is composed of rock wool and aluminum silicate ceramic fiber, which can effectively reduce the loss of heat transferred to the outside. The insulating material is alumina ceramic to ensure the electrical isolation of the heating channel.

[0039] Preferably, the length of the plate-type structure metal shell 1 (from the gas inlet 11 to the gas outlet 12) is 1000mm, the width is 500mm, the height is 50mm, and the wall thickness is 5mm; the thickness of the porous gas distribution plate 3 is 25mm; the side length of the channel 41 of the integral electric heating alloy channel assembly 4 is 40mm, the length is 500mm, and the wall thickness is 5mm.

[0040] The operation process of the Joule heat plate type electrically driven reactor of the present invention is as follows:

[0041] After the reaction gas enters the reactor through the gas inlet 11 of the plate-type structure metal shell 1, it passes through the baffle 2 and the porous gas distribution plate 3 in sequence and is evenly distributed to all parallel channels 41 of the integral electric heating alloy channel assembly 4. Under the condition of power on, the integral electric heating alloy channel assembly 4 heats up rapidly and transfers the heat directly to the surface of the catalyst 5, and the generated product gas is discharged through the gas outlet 12.

[0042] The Joule heat plate type electric driven reactor of the present invention has two working modes: reaction mode and regeneration mode. When the activity of the catalyst 5 decreases due to carbon deposition or other reasons, the reactor switches to the regeneration mode. During the regeneration process, a regeneration gas (such as oxygen or diluted air) is introduced into the reactor, and the temperature of the integral electric heating alloy channel assembly 4 is precisely controlled within the range required for regeneration (500°C to 600°C), so that the carbon deposits are removed under high temperature oxidation conditions, while avoiding sintering and damage of the active components of the catalyst. After the regeneration is completed, the reactor quickly switches back to the reaction mode to achieve continuous operation of the catalytic reaction and catalyst regeneration.

[0043] The Joule heat plate type electrically driven reactor of the present invention is suitable for strongly endothermic reaction systems, including propane dehydrogenation, methane steam / dry gas reforming and methane combined / triple reforming and other processes, providing efficient, precise and energy-saving heat support for these processes.

[0044] Example 1

[0045] The Joule heat plate type electric driven reactor of the present invention is used to verify the methane mixed reforming reaction in this example, and the conventional external wall heating reactor is used as a control. The inlet reaction gas of the two reactors is a mixed gas of methane, steam and carbon dioxide, with a molar ratio of 3:2:1 and a space velocity of 10000h -1 , the pressure is 1 bar, the inlet temperature is 650℃, and the loaded catalyst is Ni-based Raschig ring catalyst particles with a particle size of 10mm. The integral electric heating alloy channel assembly of the Joule heat plate reactor has 10 parallel channels. When the electric heating power is 12kW, the temperature at the outlet of the alloy channel is about 1050℃. At this time, the conversion rate of methane reaches about 95%. Compared with the traditional outer wall heating reactor, the overall energy utilization rate is increased by 30%. It can be seen that the use of the reactor of the present invention can significantly improve the overall energy utilization rate while ensuring the conversion rate, thereby verifying the high efficiency of the reactor of the present invention in methane mixed reforming.

[0046] Example 2

[0047] The propane dehydrogenation reaction was verified in this example using the Joule heat plate type electric driven reactor of the present invention, and a conventional external wall heating reactor was used as a control. The inlet reaction gas of the two reactors was a mixed gas of propane, hydrogen, propylene and argon, with a molar ratio of 0.35:0.06:0.04:0.55 and a space velocity of 10000h -1, the pressure is 1 bar, the inlet temperature is 600°C, and the loaded catalyst is Pt-based spherical catalyst particles with a particle size of 5 mm. The integral electric heating alloy channel assembly of the Joule heat plate reactor has 10 parallel channels. When the electric heating power is 7kW, the temperature at the outlet of the alloy channel can reach about 1000°C. At this time, the conversion rate of propane reaches about 40%, and the selectivity reaches about 90%. Compared with the traditional outer wall heating reactor, the overall energy utilization rate is improved by 30%. It can be seen that the use of the reactor of the present invention can significantly improve the overall energy utilization rate while ensuring the conversion rate, thereby verifying the high efficiency of the reactor of the present invention in propane dehydrogenation.

[0048] The specific structure and principle of the present invention are described in detail above. It should be understood that the present invention is not limited to the above-mentioned specific operation mode, and those skilled in the art can make various deformations or modifications within the scope of the specific structure and principle disclosed in the present invention, which does not affect the essential content of the present invention and also belongs to the scope of the present invention.

Claims

1. A Joule heat plate type electrically driven reactor, characterized in that: The reactor comprises a plate-type structure metal shell (1), one end of which is provided with a gas inlet (11), and the other end of which is provided with a gas outlet (12), and the interior of which is provided with a baffle (2), a porous gas distribution plate (3) and an integral electric heating alloy channel component (4) in sequence from the gas inlet (11) to the gas outlet (12), and the integral electric heating alloy channel component (4) is filled with a granular catalyst (5), and a drainage conductor (6) is also provided on the outer wall of the plate-type structure metal shell (1).

2. The Joule heat plate type electrically driven reactor according to claim 1, characterized in that: The baffle plate (2) is arranged on the inner side of the gas inlet (11) of the plate-type structure metal shell (1), and its surface (21) facing the gas inlet (11) is an inclined surface that is inclined inwardly from the center to both sides.

3. The Joule heat plate type electrically driven reactor according to claim 1, characterized in that: The porous gas distribution plate (3) is arranged behind the baffle (2); the porous gas distribution plate (3) is in a rectangular parallelepiped shape and has gas holes (31) evenly distributed in a horizontal direction.

4. The Joule heat plate type electrically driven reactor according to claim 3, characterized in that: The pores (31) have a diameter of 4 mm, and the porosity of the porous gas distribution plate (3) is 50%.

5. The Joule heat plate type electrically driven reactor according to claim 1, characterized in that: The integral electric heating alloy channel component (4) is in the shape of a rectangular parallelepiped, and its interior is divided into a plurality of parallel channels (41). The cross-section of the channels (41) is square, and all the channels (41) have the same wall thickness; the number of the channels (41) is 10 to 20.

6. The Joule heat plate type electrically driven reactor according to claim 5, characterized in that: The catalyst particles (5) are filled in the channel (41), and their shapes are selected from a combination of one or more of sphere, cylinder, clover, Raschig ring, four-hole column, and seven-hole column. The filling length is 450 mm, and the volume density is 0.75 g / cm 3 ; Support plates are installed at both the front and rear ends of the channel (41), and the support plates have a porous structure, which prevents the loss of catalyst particles (5) while ensuring smooth gas flow.

7. The Joule heat plate type electrically driven reactor according to claim 1, characterized in that: The material of the integral electric heating alloy channel component (4) is FeCrAl alloy, NiCr alloy or NiCrFe alloy, and the conductor material of the drainage conductor (6) is Fe, Cr, Ni, Al, Cu or an alloy thereof, and its resistivity is lower than the body of the integral electric heating alloy channel component (4).

8. The Joule heat plate type electrically driven reactor according to claim 1, characterized in that: The space between the outer wall of the integral electric heating alloy channel component (4) and the inner wall of the plate-type structure metal shell (1) is filled with thermal insulation cotton and insulating material.

9. The Joule heat plate type electrically driven reactor according to claim 5, characterized in that: The plate-type structural metal shell (1) has a length of 1000 mm, a width of 500 mm, a height of 50 mm, and a wall thickness of 5 mm; the porous gas distribution plate (3) has a thickness of 25 mm; the channel (41) of the integral electric heating alloy channel assembly (4) has a side length of 40 mm, a length of 500 mm, and a wall thickness of 5 mm.

10. Use of the Joule heat plate type electrically driven reactor according to any one of claims 1 to 9 in an endothermic reaction system, characterized in that: The endothermic reaction system includes methane steam reforming, dry gas reforming, mixed reforming and propane dehydrogenation.

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