Coil plate heat exchange reforming combustion integrated thermal power equipment and solid oxide power generation system

Abstract

The present application relates to a kind of roll plate heat exchange reforming combustion integrated thermal equipment and solid oxide power generation system, and thermal equipment includes: roll plate heat exchanger includes shell and four roll plates, four roll plates are sequentially spirally wound and arranged in shell around a center axis, medium passage is formed between adjacent two roll plates, including two first passages and two second passages arranged alternately, two first passages are communicated at one end of spiral center, two second passages are not communicated and isolated from first passage each other;Combustion chamber has inlet and outlet, and outlet is communicated with first passage at one end of spiral center;Wherein, two second passages are used for air and fuel flow respectively.This application integrates heat exchanger and combustion chamber, integrates air and fuel heat exchanger structure, cancels connecting pipeline, reduces heat loss, improves overall thermal efficiency and volume power density of system, and the temperature of air and fuel after heating is close, can reduce thermal stress caused by temperature difference.

Description

Technical Field

[0001] This invention relates to the field of solid oxide battery technology, specifically to a plate-type heat exchange reforming combustion integrated thermal equipment and a solid oxide power generation system. Background Technology

[0002] Solid oxide batteries (SOCs) are high-temperature energy conversion devices with advantages such as high efficiency, no pollution, compact structure, modular design, and strong fuel adaptability. When operating in solid oxide fuel cell (SOFC) mode, they directly convert the chemical energy of hydrocarbon fuels into electrical energy through electrochemical reactions; when operating in solid oxide electrolyzer (SOEC) mode, they efficiently electrolyze water and CO2 into hydrogen and CO. Their operation involves no chemical energy-thermal energy-mechanical energy conversion process and is not limited by the Carnot cycle, thus resulting in high power generation efficiency. Their operating temperature ranges from 500 to 800 degrees Celsius. o Between C and the grid, the fuel cell stack needs to be integrated with the balance of plant (BOP) system to form an independent power generation system during actual operation. The BOP mainly includes an energy storage unit (providing power during startup), a control unit (controlling and providing feedback to various system components), a gas supply unit (blower, flow meter, shut-off valve, connecting pipes, etc.), and thermal components (combustion chamber, air heat exchanger, fuel heat exchanger, reformer), etc. The operating states of the thermal components are as follows: Figure 1 As shown.

[0003] During startup of an SOFC system, ambient temperature air and fuel are preheated through heat exchangers and then introduced into the cathode and anode of the fuel cell stack for heat exchange, allowing the stack to slowly heat up to its operating temperature. During this process, the stack does not consume air or fuel; the unused air-fuel mixture enters the combustion chamber for combustion, and the resulting high-temperature flue gas is then passed through air and fuel heat exchangers to preheat the ambient temperature air and fuel. Once the stack reaches its operating temperature, it begins to discharge or electrolyze. This electrochemical reaction consumes some air and fuel, and any unreacted gases enter the combustion chamber for combustion. In SOEC mode, bypass fuel is introduced for combustion.

[0004] Currently, SOC (State-of-the-art) systems typically use three independent thermal components: a combustion chamber, an air heat exchanger, and a fuel heat exchanger (or fuel reforming heat exchanger). Each component is individually insulated and connected by piping. This design leads to the following problems during system operation: 1) Longer pipes lead to increased heat loss when high-temperature gas flows, affecting the system's thermal efficiency; 2) Excessive pipe and elbow connections increase pressure loss during gas flow, leading to increased blower load and increased power consumption of the system itself. 3) The distributed design increases the heat exchange area between thermal components and the outside environment, resulting in a decrease in system thermal efficiency; 4) Dispersed thermal components increase the volume of the BOP, resulting in a decrease in the system's volumetric power density.

[0005] 5) The air heat exchanger and fuel heat exchanger are separate. The temperature difference between the air and fuel after heat exchange is large. The temperature must be brought closer together by a thermal equalizer. Otherwise, the excessive temperature difference may cause thermal stress runaway and damage the fuel cell stack. Summary of the Invention

[0006] Based on the above description, the present invention provides a plate-type heat exchange reforming combustion integrated thermal equipment and a solid oxide power generation system to solve the problems existing in the prior art.

[0007] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: In a first aspect, this application provides a plate-type heat exchange reforming combustion integrated thermal equipment, comprising: A plate heat exchanger includes a shell and four plates disposed within the shell. The four plates are spirally wound around a central axis and disposed in the shell. A medium channel is formed between two adjacent plates. The four channels include two first channels and two second channels. The two first channels and two second channels are arranged alternately. The two first channels are interconnected at one end of the spiral center, and the two second channels are not interconnected and are isolated from the first channels. A combustion chamber having an inlet and an outlet, the outlet being connected to one end of the first channel at the center of the spiral; The two second channels are used for air and fuel circulation, respectively.

[0008] Preferably, the second channel for fuel flow has two inlets, both located at one end of the second channel at the center of the spiral, and the two inlets are located on both sides of the second channel along the central axis. The two inlets of the second channel are used to introduce water and fuel, respectively.

[0009] Preferably, the combustion chamber and the plate heat exchanger are axially distributed along the central axis.

[0010] Preferably, it also includes an evaporator coil wound around the combustion chamber, the outlet of the evaporator coil being connected to one of the inlets of the second channel for fuel flow.

[0011] Preferably, both the first channel and the second channel have an outlet at the end furthest from the spiral center.

[0012] Preferably, the four coiled plates are spirally wound sequentially around the combustion chamber.

[0013] Preferably, the combustion chamber has two outlets located on the side wall, and the two outlets are respectively connected to one end of the two first channels at the center of the spiral, and the two first channels are connected through the combustion chamber.

[0014] Preferably, the combustion chamber is cylindrical and coaxial with the central axis.

[0015] Secondly, this application provides a solid oxide power generation system, including the integrated thermal equipment for heat exchange, reforming, and combustion as described above. Compared with the prior art, the technical solution of this application has at least the following beneficial technical effects: 1. This application integrates the heat exchanger and combustion chamber into a single unit by designing the plate heat exchanger internally with four channels. This reduces the number and length of connecting pipes, shortens the flow path of the high-temperature gas, and decreases heat loss and local resistance to gas flow, thereby improving system thermal efficiency and reducing blower load and system self-consumption. The integrated design makes the thermal components more compact, reduces the overall heat exchange area with the outside environment, and improves the overall system thermal efficiency and volumetric power density. Simultaneous heating of air and fuel with the same high-temperature gas results in similar temperatures for both, reducing thermal stress caused by temperature differences.

[0016] 2. One aspect of this application involves arranging the combustion chambers axially along the central axis and installing evaporator coils around the combustion chamber. The heat emitted by the combustion chamber during operation can be used to heat the water inside the evaporator coils. After heating, the water is introduced into the second channel to mix with the fuel, providing the necessary steam source for the fuel reforming reaction. This recovers the heat loss from the combustion chamber, further improving the overall thermal efficiency of the system and avoiding overheating damage to the combustion chamber. On the other hand, it simplifies the reforming process and equipment structure. The evaporator coils around the combustion chamber make full use of the space around the combustion chamber, making the equipment more compact.

[0017] 3. Another embodiment of this application designs the combustion chamber to be inserted into the heat exchanger, with four spiral plates wound around the outside of the combustion chamber in sequence. The pipe connection between the combustion chamber and the heat exchanger is eliminated. The high-temperature flue gas generated by fuel combustion in the combustion chamber is directly introduced into the first channel, which further improves the thermal energy utilization efficiency, reduces the pressure loss of the gas, reduces the load on the blower, and the heat dissipated from the combustion chamber is directly absorbed by the heat exchanger, avoiding thermal runaway of the combustion chamber.

[0018] 4. This application designs the heat exchanger's internal structure to form two first channels (flue gas channels) and two second channels (air and fuel channels). Each second channel is adjacent to a first channel on both sides. Designers can adjust parameters such as the flow cross-sectional area of ​​the air and fuel channels to achieve different heat exchange capacities based on the differences in preheating heat required by air and fuel, thus achieving on-demand heat distribution within the same plate heat exchanger. Simultaneously, the two flue gas channels are interconnected at the spiral center, allowing for automatic flow distribution and pressure balance of the high-temperature flue gas from the combustion chamber between the two first channels, further ensuring heat matching during the heat exchange process. Compared to traditional decentralized structures, this application avoids the problem of uncoordinated heat differences between the air and fuel heat exchangers due to independent design, and also reduces heat loss during combustion process. This ensures that both air and fuel can be preheated to the target temperature, optimizing the heat exchanger's structural dimensions and improving the overall system thermal efficiency. Attached Figure Description

[0019] Figure 1 The accompanying drawings are for the background art of this invention; Figure 2 This is a schematic diagram of the first embodiment of the integrated thermal equipment for heat exchange, reforming, and combustion provided in this invention. Figure 3 This is a schematic diagram of the internal structure of the plate heat exchanger in the first embodiment of the plate heat exchanger reforming combustion integrated thermal equipment provided in this invention. Figure 4 This is a schematic diagram of a second embodiment of the integrated thermal equipment for heat exchange, reforming, and combustion provided in this invention. Figure 5 This is a schematic diagram of the internal structure of the plate heat exchanger in a second embodiment of the integrated thermal equipment for reforming and combustion provided in this invention. Figure 6 This is a schematic diagram of the combustion chamber and swirl generator in a second embodiment of the integrated thermal equipment for heat exchange, reforming, and combustion provided in this invention.

[0020] Explanation of reference numerals in the attached figures: 1. Plate heat exchanger; 11. Shell; 12. Plate; 13. First channel; 14. Second channel; 2. Combustion chamber; 3. Evaporator coil; 4. Swirler. Detailed Implementation

[0021] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0023] It is understood that spatial relation terms such as "below," "under," "below," "below," "above," "above," etc., can be used here to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, the element or feature described as "below" or "below" of the other element or feature will be oriented "above" the other element or feature. Therefore, the exemplary terms "below" and "below" can include both upper and lower orientations. Furthermore, the device may also include other orientations (e.g., rotated 90 degrees or other orientations), and the spatial descriptive terms used herein will be interpreted accordingly.

[0024] It should be noted that when one element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intermediary element. In the following embodiments, "connection" should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have the transmission of electrical signals or data between them.

[0025] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising,” “including,” or “having,” etc., specify the presence of the stated feature, whole, step, operation, component, part, or combination thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof.

[0026] Reference Figure 2 As shown, this application provides a plate-type heat exchange reforming combustion integrated thermal equipment, which includes a plate heat exchanger 1 and a combustion chamber 2. The plate heat exchanger 1 is used for preheating the air and fuel required for the operation of the fuel cell stack, while the combustion chamber 2 provides the heat required for preheating personnel.

[0027] Reference Figure 3 As shown, the plate heat exchanger 1 includes a shell 11 and four plates 12 disposed inside the shell 11. The four plates 12 are spirally wound around a central axis and disposed in the shell 11. A medium channel is formed between two adjacent plates 12. The four channels include two first channels 13 and two second channels 14. The two first channels 13 and the two second channels 14 are arranged alternately. The two first channels 13 are connected to each other at one end of the spiral center. The two second channels 14 are not connected to each other and are isolated from the first channels 13.

[0028] This design integrates the air heat exchanger and fuel heat exchanger into a single unit, eliminating the need for connecting pipes and improving system thermal efficiency. The integrated design makes the heat exchanger more compact, reducing the overall heat exchange area with the environment and increasing the overall system thermal efficiency and volumetric power density.

[0029] Specifically, during manufacturing, the coil plate 12 is fixed to the inner wall of the housing 11 on both sides of the central axis axial direction, so that the formed medium channel is closed on both sides of the central axis axial direction, allowing the medium to flow only from the end closer to the spiral center to the end farther from the spiral center or in the reverse direction within the medium channel. The two coil plates 12 on both sides of each second channel 14 are connected to each other at the spiral center end to isolate the second channel 14 from the first channel 13.

[0030] The parameters such as the number of coils, spacing, and width of the coil plate 12 can be designed by technicians based on the actual heat exchange requirements.

[0031] Reference Figure 2 and Figure 3 As shown, in this embodiment, the medium inlets of both the first channel 13 and the second channel 14 are located at one end of the spiral center, while the outlets are both located at the end away from the spiral center. Specifically, the second channel 14, which supplies fuel, has two inlets for water and fuel, respectively. Both inlets are located at the spiral center of the second channel 14 and are axially positioned on opposite sides of the central axis. This second channel 14 serves as a reforming gas channel for mixing steam and fuel for a reforming reaction. The second channel 14, which supplies air, has only one inlet, which is axially positioned on the same side of the heat exchanger as the fuel inlet of the other second channel 14.

[0032] The combustion chamber 2 is used for the mixing and combustion of fuel and air. The resulting high-temperature exhaust gas is fed into the plate heat exchanger 1 to preheat the air and fuel.

[0033] Reference Figure 2As shown, in the first embodiment of this example, the combustion chamber 2 and the plate heat exchanger 1 are axially distributed along the central axis, and the outlet of the combustion chamber 2 is connected to the first channel 13 of the plate heat exchanger 1 through a pipe.

[0034] Reference Figure 2 As shown, specifically in this embodiment, the burner is located outside the plate heat exchanger 1. In order to reduce the heat loss of the burner, an evaporator coil 3 is provided outside the burner. The evaporator coil 3 is coiled around the outside of the combustion chamber 2, and the outlet of the evaporator coil 3 is connected to one of the inlets of the second channel 14 for fuel flow.

[0035] By setting up the evaporator coil 3, water passes through the evaporator coil 3 before being injected into the reforming gas channel. The water in the evaporator coil 3 is heated by the heat emitted by the combustion chamber 2 when it is working. After being heated, the water is introduced into the second channel 14 to mix with the fuel, providing the water vapor source required for the fuel reforming reaction. On the one hand, the heat loss of the combustion chamber 2 is recovered, further improving the overall thermal efficiency of the system and avoiding overheating damage to the combustion chamber 2. On the other hand, the reforming process and equipment structure are simplified. The evaporator coil 3 is coiled around the combustion chamber 2, making full use of the space around the combustion chamber 2, making the equipment more compact.

[0036] In this embodiment, the combustion chamber 2 is cylindrical with its inlet and outlet located at both ends.

[0037] Reference Figure 4 and Figure 5 As shown, in the second embodiment of this invention, four spiral plates 12 are sequentially spirally wound around the outside of the combustion chamber 2. Furthermore, the combustion chamber 2 has two outlets located on the side wall, and each outlet is connected to one end of a first channel 13 at the center of the spiral, with the two first channels 13 connected through the combustion chamber 2.

[0038] Specifically, in the design, a hole extending axially through both ends along the central axis is provided in the middle of the plate heat exchanger 1. The combustion chamber 2 is placed inside the hole, so that the end of the plate 12 near the spiral center is connected and fixed to the shell 11 of the combustion chamber 2, forming a seal between the shell 11 of the combustion chamber 2 and the heat exchanger shell. Thus, the combustion chamber 2 and the plate heat exchanger 1 are integrated into one unit, eliminating the need for pipe connections between the combustion chamber 2 and the heat exchanger. The high-temperature flue gas generated by fuel combustion in the combustion chamber 2 is directly introduced into the first channel 13, further improving thermal energy utilization efficiency. This also reduces gas pressure loss, lowers the blower load, and the heat dissipated from the combustion chamber 2 is directly absorbed by the heat exchanger, reducing the risk of thermal runaway in the combustion chamber 2.

[0039] In this embodiment, the combustion chamber 2 is also designed to be cylindrical, with the inlet located at one end and two outlets located on the side walls on opposite sides.

[0040] Reference Figure 6 As shown, in order to ensure stable combustion of fuel in the fuel chamber, a swirl starter 4 is provided at the inlet end of the combustion chamber 2. The swirl starter 4 is a cylindrical shape coaxial with the combustion chamber 2, with one end closed and the other end connected to the combustion chamber 2. The swirl starter 4 has two inlets on its side wall, which are located on opposite sides of the side wall. Gas injected from the inlets is injected into the swirl starter 4 along the tangential direction of the swirl starter 4.

[0041] The swirl generator 4 allows the injected fuel and air to enter tangentially. The strong shearing effect generated by the tangential injection helps the fuel and oxidant mix quickly, making the combustion more complete and reducing the risk of unstable combustion oscillations. The fuel and air generate a rotating flow in the cylindrical chamber, forming a stable swirling field. After the swirling airflow enters the combustion chamber 2, a low-pressure zone is formed in the central area, which causes the high-temperature gas that has already been burned downstream to flow back to the vicinity of the inlet, continuously heating and igniting the newly entered fuel and air mixture. This self-sustaining recirculation heating mechanism does not require external ignition energy to ensure the continuous and stable existence of the flame, avoiding flame detachment or extinguishing due to excessive airflow velocity, thereby achieving stable combustion in the combustion chamber 2.

[0042] In this embodiment, an external water source is directly connected to the water inlet of the reforming gas channel to inject water into the reforming gas channel.

[0043] For the two implementation methods described above, interfaces can be set at the entrance and exit of each channel according to actual needs during the design phase to connect to the corresponding equipment or pipelines.

[0044] This embodiment also provides a solid oxide power generation system including the plate-type heat exchange, reforming, and combustion integrated thermal equipment as described above. The specific system structure is conventional technology for those skilled in the art and will not be elaborated here.

[0045] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A plate-type heat exchange, reforming, and combustion integrated thermal equipment, characterized in that, include: A plate heat exchanger (1) includes a shell (11) and four plates (12) disposed in the shell (11). The four plates (12) are spirally wound around a central axis and disposed in the shell (11). A medium channel is formed between two adjacent plates (12). The four channels include two first channels (13) and two second channels (14). The two first channels (13) and the two second channels (14) are arranged alternately. The two first channels (13) are connected to each other at one end of the spiral center. The two second channels (14) are not connected to each other and are isolated from the first channels (13). Combustion chamber (2) having an inlet and an outlet, the outlet being connected to one end of the first channel (13) at the center of the spiral; The two second channels (14) are used for air and fuel circulation, respectively.

2. The integrated thermal equipment for heat exchange, reforming, and combustion according to claim 1, characterized in that: The second channel (14) for fuel flow has two inlets, both located at one end of the second channel (14) at the spiral center, and the two inlets are located on both sides of the second channel (14) axially along the central axis. The two inlets of the second channel (14) are used to introduce water and fuel, respectively.

3. The integrated thermal equipment for heat exchange, reforming, and combustion according to claim 2, characterized in that: The combustion chamber (2) and the plate heat exchanger (1) are axially distributed along the central axis.

4. The integrated thermal equipment for heat exchange, reforming, and combustion according to claim 3, characterized in that: It also includes an evaporator coil (3) which is coiled around the outside of the combustion chamber (2) and whose outlet is connected to one of the inlets of the second channel (14) for fuel flow.

5. The integrated thermal equipment for heat exchange, reforming, and combustion according to claim 1, characterized in that: Both the first channel (13) and the second channel (14) have an outlet at the end away from the spiral center.

6. The integrated thermal equipment for heat exchange, reforming, and combustion according to claim 1, characterized in that: The four coil plates (12) are spirally wound around the outside of the combustion chamber (2) in sequence.

7. The integrated thermal equipment for heat exchange, reforming, and combustion according to claim 6, characterized in that: The combustion chamber (2) has two outlets located on the side wall. The two outlets are connected to two first channels (13) at one end of the spiral center, and the two first channels (13) are connected through the combustion chamber (2).

8. The integrated thermal equipment for heat exchange, reforming, and combustion according to claim 1, characterized in that: The combustion chamber (2) is cylindrical and coaxial with the central axis.

9. A solid oxide power generation system, characterized in that: Includes the integrated thermal equipment for heat exchange, reforming, and combustion as described in any one of claims 1-8.

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