A multifunctional burner for a solid oxide fuel cell system

Abstract

The application provides a multifunctional combustor for a solid oxide fuel cell system, comprising an igniter, a fuel gas inlet pipe, a fuel feeding assembly, an air inlet pipe, an air inlet assembly, a fuel liquid inlet pipe, a flow guide, and a combustion chamber; the flow guide comprises a plurality of flow channel plates arranged in parallel; each flow channel plate is provided with fuel flow channels and air flow channels arranged at intervals on two sides of the flow channel plate; the flow channels are communicated with the combustion chamber; the fuel gas inlet pipe and the fuel liquid inlet pipe are communicated with the fuel feeding assembly; the fuel feeding assembly is communicated with feeding ports of the fuel flow channels; the air inlet pipe is communicated with the air inlet assembly; and the air inlet assembly is communicated with air inlet ports of the air flow channels. The combustor realizes a gas-liquid mixed feeding mode, reasonably utilizes fuel tail gas of a stack system, avoids local high temperature and deflagration by the interval arrangement of the flow channels, and enables the fuel gas and the air to be fully mixed by the large effective contact surface at the outlet of the flow channels, thereby improving the energy conversion efficiency of the combustor.

Description

Technical Field

[0001] This invention relates to a burner, and more particularly to a multifunctional burner for a solid oxide fuel cell system. Background Technology

[0002] Solid oxide fuel cells (SOFCs) are efficient and clean energy conversion devices. SOFCs offer high fuel flexibility, using not only conventional hydrogen but also carbon monoxide, methane, methanol, and ethanol. However, SOFCs have stringent operating temperature requirements, typically between 600℃ and 1000℃. Therefore, conventional high-power SOFC stacks using methanol and other fuels usually employ external reforming, requiring an external heat supply, which reduces the overall energy conversion efficiency of the SOFC. Secondly, to avoid anodic oxidation and high concentration polarization, the fuel utilization rate of the SOFC stack cannot be set too high, approximately 60-90%. Therefore, about 10-40% of the fuel gas enters the exhaust gas and cannot be used for power generation. If this portion of fuel gas is directly discharged, it results in significant waste, and the energy utilization efficiency of the battery power generation system will be greatly reduced.

[0003] The burner for solid oxide fuel cells (SOFCs), as a core component of the thermal balance system, presents a significant challenge in SOFC system design. The burner needs to provide a heat source for the system during the heating phase of a high-power SOFC stack, achieving overall system temperature rise and ensuring the stack meets the temperature requirements for power generation. However, existing SOFC burners suffer from low energy efficiency, cannot mix gas and liquid feedstocks, resulting in uneven fuel mixing, unstable heating, and even defects such as deflagration. Summary of the Invention

[0004] The purpose of this invention is to provide a multifunctional burner for solid oxide fuel cell systems, which enables gas-liquid mixing during burner feeding, resulting in more uniform fuel mixing, avoiding localized high temperatures and deflagration during combustion, and improving the energy conversion efficiency of the burner.

[0005] To achieve the above objectives, the present invention provides a multifunctional burner for a solid oxide fuel cell system, comprising:

[0006] Combustion chamber, wherein an igniter is provided;

[0007] A flow deflector, comprising multiple parallel flow channel plates, with a fuel flow channel and an air flow channel formed on both sides of each flow channel plate, and the outlets of the fuel flow channel and the air flow channel communicating with the combustion chamber;

[0008] Gas inlet pipe, used to transport gaseous fuel;

[0009] A fuel liquid inlet pipe for conveying liquid fuel;

[0010] A fuel feeding assembly, the fuel gas inlet pipe and the fuel liquid inlet pipe being communicated with the fuel feeding assembly, the fuel feeding assembly being communicated with the inlet of the fuel flow channel;

[0011] An air inlet pipe for conveying hot air;

[0012] An air inlet assembly, the air inlet pipe being communicated with the air inlet assembly, the air inlet assembly being communicated with the air flow channel inlet.

[0013] The combustor of the present application can provide liquid fuel to the combustion chamber through the fuel liquid inlet pipe and can provide gas fuel to the combustion chamber through the fuel gas inlet pipe, realizing the gas-liquid mixed use of fuel.

[0014] Further, each flow channel plate of the flow guide comprises a plate body and flow guide fins, and the flow guide fins enclose the fuel flow channel and the air flow channel on the plate body respectively.

[0015] Further, the fuel flow channel is an L-shaped flow channel enclosed by three flow guide fins respectively located at the edges of the plate body, and the plate body is provided with a fuel flow channel inlet and outlet at the positions not covered by the flow guide fins.

[0016] Further, the air flow channel is a straight flow channel enclosed by two flow guide fins respectively located at the edges of the plate body, and the two edges of the plate body not covered by the flow guide fins are respectively an air flow channel inlet and outlet.

[0017] The flow guide fins enclose the flow channel structure on the plate body, and the effective area of the inlet, outlet, inlet and outlet formed by the flow channel structure is large, so that the fuel gas in the fuel flow channel and the air in the air flow channel can be more fully and uniformly mixed in the combustion chamber, thereby improving the energy conversion efficiency of the combustor.

[0018] Further, the flow guide fins are welded on the plate body by spot welding. Unlike the conventional whole welding method, the spot welding method is more time-saving and labor-saving.

[0019] Further, the gaps between the guide vanes of all adjacent two layers of flow channel plates are sealed by argon arc welding. The argon arc welding method is to weld the multiple layers of flow channel plates first, then weld the outer side of the burner, and when leakage is found during leakage detection, the processing can be reprocessed. Unlike other manufacturing processes, the welding is in the inner layer of the burner, and if the leakage is found to be unqualified, the entire burner cannot be repaired, so the waste rate of the welding process is greatly reduced.

[0020] Further, the two sides of the multiple parallel flow channel plates are respectively provided with a sealing plate for clamping and sealing the flow guide.

[0021] Further, a standby igniter is arranged on the combustion chamber, and the standby igniter (7) is an open flame igniter. When the igniter fails to ignite or fails, the standby open flame igniter can be used to ignite the combustion chamber.

[0022] Further, a thermocouple is arranged in the combustion chamber. The thermocouple is used to monitor the temperature in the combustion chamber.

[0023] Further, a liquid level meter is arranged on the fuel feeding assembly. The liquid level meter is used to monitor the liquid level of the liquid fuel in the fuel feeding assembly, so as to more accurately control the flow rate and flow of the fuel liquid inlet pipe.

[0024] Compared with other prior art, the present application has the following beneficial effects:

[0025] (1) The burner of the present application realizes the gas-liquid mixed feeding mode to provide the required heat for the stack system. The burner supplies the liquid fuel in the fuel liquid inlet pipe to the combustion chamber before the solid oxide fuel cell stack is operated to generate heat, and the generated heat is used as the heat source for the overall temperature rise of the system during the temperature rise stage of the solid oxide fuel cell stack, so that the stack meets the requirements of the power generation working condition. After the stack system starts to generate power, the fuel liquid inlet pipe is closed, and the combustion tail gas of the stack system enters the combustion chamber through the fuel gas inlet pipe for combustion, and the generated heat source gas continues to supply the heat exchanger and the reformer and other equipment in the stack system, so that the fuel utilization rate of the stack system reaches more than 85%.

[0026] (2) The flow channel structure of the burner designed in the present application is a same-direction parallel flow structure of fuel and air. By controlling the specific flow rate parameters, the same-direction and same-speed effect is achieved, so that the fuel and air remain uniform in the advancing route in the flow channel during the combustion process, and the local high temperature and deflagration phenomenon is avoided. At the same time, the effective contact surface of the same-direction and same-speed parallel and interval arrangement of the flow channel structure at the outlet of the flow channel is large, and the fuel gas and air can be fully and uniformly mixed and diffused outside the outlet of the flow channel, so that the fuel gas can be more fully burned, thereby improving the energy conversion efficiency of the burner. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 A perspective view of a multifunctional burner for a solid oxide fuel cell system according to an embodiment of the present application;

[0028] Figure 2 A flow channel structure of a burner according to an embodiment of the present application;

[0029] Figure 3 A flow channel plate stack structure of a burner according to an embodiment of the present application.

[0030] BRIEF DESCRIPTION OF DRAWINGS

[0031] 1 - igniter, 2 - fuel gas inlet pipe, 201 - fuel feeding assembly, 3 - air inlet pipe, 301 - air inlet assembly, 4 - fuel liquid inlet pipe, 5 - flow guide, 501 - plate body, 502 - flow guide fin, 503 - feeding port, 504 - discharging port, 505 - air inlet port, 506 - air outlet port, 510 - fuel flow channel, 511 - air flow channel, 6 - combustion chamber, 7 - backup igniter, 8 - liquid level meter, 9 - sealing plate, 10 - thermocouple. DETAILED DESCRIPTION

[0032] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will be combined with the accompanying drawings for the embodiments of the present application to make a clear and complete description of the technical solutions of the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the accompanying drawings can be arranged and designed in various different configurations.

[0033] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of the present application.

[0034] It should be noted that: similar signs and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0035] In the description of the present application, it should be noted that the terms "upper", "lower", "left", "right", "inner", "outer", "front", "back" and the like indicate the orientation or positional relationship shown in the drawings or the orientation or positional relationship commonly used when the product of the present application is used, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0036] The preferred embodiments of the present application will be described below in conjunction with the drawings, in which it should be understood that the preferred embodiments described herein are intended to illustrate and explain the present application, and are not intended to limit the present application.

[0037] As shown in Figure 1 and Figure 2 , the present embodiment provides a multifunctional burner for a solid oxide fuel cell system, which comprises an igniter 1, a fuel gas inlet pipe 2, a fuel feeding assembly 201, an air inlet pipe 3, an air inlet assembly 301, a fuel liquid inlet pipe 4, a flow guide 5, and a combustion chamber 6. The igniter 1 is arranged in the combustion chamber 6. The flow guide 5 comprises a plurality of flow channel plates arranged in parallel. Each flow channel plate has a fuel flow channel 510 and an air flow channel 511 formed on both sides thereof. The discharge port 504 of the fuel flow channel 510 and the air outlet 506 of the air flow channel 511 are in communication with the combustion chamber 6. The fuel gas inlet pipe 2 and the fuel liquid inlet pipe 4 are in communication with the fuel feeding assembly 201. The fuel feeding assembly 201 is in communication with the feeding port 503 of the fuel flow channel 510. The air inlet pipe 3 is in communication with the air inlet assembly 301. The air inlet assembly 301 is in communication with the air inlet port 505 of the air flow channel 511.

[0038] As shown in Figure 2 , the fuel flow channel 510 is an L-shaped flow channel surrounded by three flow guide plates 502 located at the edges of the plate body 501. The feeding port 503 and the discharge port 504 of the fuel flow channel 510 are arranged on the plate body 501 where the flow guide plates 502 are not covered. The air flow channel 511 is a straight flow channel surrounded by two flow guide plates 502 located at the opposite edges of the plate body 501. The lengths of the two flow guide plates 502 are the same as the length of the plate body 501. The air inlet port 505 and the air outlet 506 of the air flow channel 511 are arranged on the two edges of the plate body 501 where the flow guide plates 502 are not covered. The discharge port 504 of the fuel flow channel 510 and the air outlet 506 of the air flow channel 511 are in communication with the combustion chamber 6, as shown in Figure 2As shown by the arrows, fuel enters the fuel flow channel 510 from the fuel feeding assembly 201 on the left side of the feeding port 503 through the feeding port 503, air enters the air flow channel 511 from the air feeding assembly 301 below through the air inlet 505, the liquid fuel in the fuel flow channel 510 exchanges heat with the preheated air in the air flow channel 511, vaporizes the liquid fuel in the fuel flow channel 510, and then flows out of the discharge port 504, the vaporized fuel gas mixes with the air flowing out of the air outlet 506, and then enters the combustion chamber 6 together. The guide vanes 502 on each layer of flow channel plate 5 are welded on the plate body 501 by spot welding, which is different from the conventional whole welding method, and the spot welding method is more time-saving and labor-saving.

[0039] In combination Figure 3 As shown, the same flow channel side of the adjacent two flow channel plates is in contact and stacked to form the parallel arranged flow channel plates, the fuel flow channel 510 of the adjacent two flow channel plates is mirror image arranged, the guide vanes 502 of the adjacent two flow channel plates are completely overlapped when stacked, the fuel flow channel 510 and the air flow channel 511 in the flow guide 5 are parallel and spaced, the fuel gas in the discharge port 504 and the air in the air outlet 506 flow into the combustion chamber 6 in the same direction, the same speed and parallel, by controlling the specific flow rate parameters to achieve the same speed and same direction effect, so that the fuel and air keep uniform in the advancing route in the flow channel during the combustion process, and the local high temperature and deflagration phenomenon are avoided. At the same time, the effective contact surface of the flow channel structure arranged in the same direction, same speed and parallel is large at the flow channel outlet, the fuel gas and air can be fully and uniformly mixed at the flow channel outlet, so that the mixed gas can be more fully burned in the combustion chamber 6, thereby improving the energy conversion efficiency of the burner. The sealing plate 9 is used to clamp and seal the flow guide 5. The gap between the guide vanes 502 of the adjacent two flow channel plates is welded by argon arc welding to form a seal, the multi-layer flow channel plate is welded first, and then the outer side of the burner is welded. When leakage is found during leakage detection, reprocessing can be performed, so that the waste rate of the welding process is greatly reduced.

[0040] In combination Figure 1 As shown, the combustion chamber 6 is provided with a thermocouple 10 for monitoring the temperature in the combustion chamber 6. The combustion chamber 6 is provided with a backup igniter 7, which can ignite the combustion chamber 6 when the igniter 1 fails to ignite or fails. The fuel feeding assembly 201 is provided with a liquid level meter 8 for monitoring the liquid level position of the liquid fuel in the fuel feeding assembly 201, so as to more accurately control the flow rate and flow of the fuel liquid inlet pipe.

[0041] The operation process of the burner in the embodiment is as follows: before the solid oxide fuel cell stack is operated, the fuel liquid (such as liquid fuel of methanol or ethanol) in the fuel liquid inlet pipe 4 of the burner enters the fuel flow channel 510 from the feeding port 503 after passing through the fuel feeding assembly 201, and the preheated air in the air inlet pipe 3 enters the air flow channel 511 through the air inlet port 505 after passing through the air inlet assembly 301; at this time, the liquid fuel in the fuel flow channel 510 exchanges heat with the preheated air in the air flow channel 511, so that the liquid fuel in the fuel flow channel 510 is vaporized and flows out from the discharging port 504 and mixes with the air flowing out from the air outlet port 506 to form mixed fuel gas; the mixed fuel gas is ignited by the igniter 1 and burns in the combustion chamber 6 to generate heat. After that, the heat generated by the combustion in the combustion chamber 6 is used as the heat source for the heating-up stage of the solid oxide fuel cell stack system to realize the overall heating-up of the system, so that the stack meets the requirements of the power generation working condition; after the stack system starts to generate power, the fuel liquid inlet pipe 4 is closed, the combustion tail gas of the stack system enters the fuel flow channel 510 through the fuel inlet pipe 2 after passing through the fuel feeding assembly 201, and then enters the combustion chamber 6 after mixing with the air flowing out from the air outlet port 506; the heat source gas generated by the combustion in the combustion chamber 6 continues to supply the heat exchanger and the reformer and other devices in the stack system, so as to maintain the operation of the entire stack system. The burner of the present application realizes the gas-liquid mixed feeding mode, not only provides the required heat for the operation of the solid oxide fuel cell stack system, but also utilizes the combustion tail gas of the stack system to make the fuel utilization rate of the stack system reach more than 85%.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not limited thereto; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A multifunctional burner for a solid oxide fuel cell system, characterized by, The utility model relates to a kind of gas combustion device, including Combustion chamber (6), which is provided with an igniter (1) inside; Flow guide (5), which includes a plurality of flow channel plates arranged in parallel, each of the flow channel plates has fuel flow channels (510) and air flow channels (511) arranged in parallel and spaced apart in the same direction formed on both sides thereof, and the outlets of the fuel flow channels (510) and the air flow channels (511) are communicated with the combustion chamber (6); Gas inlet pipe (2) for conveying gaseous fuel; Liquid fuel inlet pipe (4) for conveying liquid fuel; Fuel feeding assembly (201), which is communicated with the gas inlet pipe (2) and the liquid fuel inlet pipe (4), and communicated with the inlets of the fuel flow channels (510); Air inlet pipe (3) for conveying hot air; Air inlet assembly (301), which is communicated with the air inlet pipe (3) and communicated with the inlets of the air flow channels (511).

2. The multifunctional burner for a solid oxide fuel cell system according to claim 1, characterized by, Each of the flow channel plates of the flow guide (5) includes a plate body (501) and flow guide fins (502) formed around the fuel flow channels (510) and the air flow channels (511) on the plate body (501).

3. The multifunctional burner for a solid oxide fuel cell system according to claim 2, characterized by, The fuel flow channels (510) are L-shaped flow channels formed by three flow guide fins (502) respectively located on the edges of the plate body (501), and the plate body (501) is provided with a fuel inlet (503) and a fuel outlet (504) at positions not covered by the flow guide fins (502).

4. The multifunctional burner for a solid oxide fuel cell system according to claim 2, characterized by, The air flow channels (511) are straight flow channels formed by two flow guide fins (502) respectively located on the opposite edges of the plate body (501), and the two edges of the plate body (501) not covered by the flow guide fins (502) are respectively an air inlet (505) and an air outlet (506) of the air flow channels (511).

5. The multifunctional burner for a solid oxide fuel cell system according to any one of claims 2 to 4, characterized by, The flow guide fins (502) are welded on the plate body (501) by spot welding.

6. The multifunctional burner for a solid oxide fuel cell system according to any one of claims 2 to 4, characterized by, The gaps between the flow guide fins (502) of all adjacent flow channel plates are sealed by argon arc welding.

7. The multifunctional burner for a solid oxide fuel cell system according to claim 1, characterized by, Each of the two sides of the plurality of flow channel plates arranged in parallel is provided with a sealing plate (9) for clamping and sealing the flow guide (5).

8. The multifunctional burner for a solid oxide fuel cell system according to claim 1, characterized by, The combustion chamber (6) is provided with a standby igniter (7), which is an open flame igniter.

9. The multifunctional burner for a solid oxide fuel cell system according to claim 1, characterized by, The combustion chamber (6) is provided with a thermocouple (10).

10. The multifunctional burner for a solid oxide fuel cell system according to claim 1, characterized by, The fuel feeding assembly (201) is provided with a liquid level meter (8).

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