Multifunctional high-efficiency energy-saving SOFC tail gas burner

Abstract

This invention relates to the field of multi-component integration technology for solid oxide fuel cell systems, specifically providing a multifunctional, high-efficiency, and energy-saving SOFC tail gas burner. This burner employs a center-periphery layered integrated structure, with the tail gas combustion chamber at its center: the lower part of the inner central layer houses the tail gas combustion chamber, equipped with an ignition detector and multiple air inlets; the upper part of the inner central layer houses an air preheater chamber; the lower outer layer nests a reformer reaction chamber containing a catalyst; and the upper outer layer, along the flue gas discharge direction, sequentially houses a fuel gas preheater chamber and an evaporator chamber, all arranged in stainless steel coils within the high-temperature flue gas channel. This invention integrates the tail gas burner, air preheater, reformer, fuel gas preheater, and evaporator into a single unit. Uniform gas distribution is achieved through various distribution chambers and adjustment holes, shortening the heat transfer path, enabling cascaded energy utilization, significantly improving system thermal efficiency, reducing volume, and meeting different power requirements in distributed scenarios.

Description

Technical Field

[0001] This invention belongs to the cross-technical field of multi-component integration and full-process energy cascade utilization of solid oxide fuel cell (SOFC) systems. Specifically, it relates to a high-efficiency and energy-saving tail gas treatment device with the tail burner as the core, which integrates an air preheater, a reformer, a fuel gas preheater, and an evaporator. Background Technology

[0002] In current SOFC systems, exhaust gas treatment (tail combustor), fuel preparation (reformer), medium preheating (air preheater, fuel gas preheater), and steam generation (evaporator) are mostly arranged in separate units, which presents the following key technical challenges: First, there is a large heat loss and low energy utilization: each component operates independently and requires a temperature box for insulation. During the process of transporting high-temperature flue gas from the tail burner to the preheater and reformer, the heat loss rate is as high as 15%-25% due to the long pipelines and many interfaces. Secondly, the structure is complex and the layout is inflexible: the split components require a large number of pipelines to connect, the system is huge (more than 50% larger than the integrated type for the same power), and the power of each component is fixed, making it difficult to adapt to the "small space, high power requirements" in distributed scenarios (such as 5-20kW for home use and 100-500kW for industrial parks); the installation cycle is long (40% longer than the integrated type) and the operation and maintenance costs are high. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the present invention aims to provide a multifunctional, high-efficiency, and energy-saving SOFC exhaust gas burner that achieves deep integration of multiple components, shortens the heat transfer path, reduces system heat loss, and improves energy cascade utilization efficiency.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a multifunctional, high-efficiency and energy-saving SOFC tail gas burner, which takes the tail gas combustion chamber as the center and adopts a center-periphery layered integrated structure to integrate the tail gas combustion chamber, air preheater chamber, reformer reaction chamber, fuel gas preheater chamber and evaporator chamber into the same structural unit, and is provided with an external heat-insulating shell; The lower part of the internal central layer is equipped with a tail gas combustion chamber, which is equipped with an ignition detector. The bottom is equipped with an anode tail gas inlet, a fuel gas inlet, a combustion air inlet, and a cathode tail gas inlet. An air preheater chamber is set in the upper part of the internal central layer. The upper part of the chamber is an air buffer zone, which is the area between two porous partition plates. Both porous partition plates are provided with air diversion holes and flue gas diversion channels. The lower part is the air heat exchange zone, with an air inlet on one side. After entering the air inlet, the air is evenly distributed through the air diversion chamber and then enters the air buffer zone. It then enters the air heat exchange zone through the air diversion holes at the bottom of the air buffer zone. The preheated hot air flows through the reformer reaction chamber through the air diversion channel, then enters the hot air confluence chamber and is discharged from the hot air outlet. The outermost layer is a nested reformer reaction chamber located outside the combustion chamber of the tail burner. The reformer reaction chamber consists of a bottom hot air manifold and a reformed gas manifold, a top mixed gas splitting chamber, and a middle reforming chamber. The reforming chamber is filled with a catalyst, and two porous partition plates are provided at its upper and lower ends. A reformed gas outlet is provided at the outside of the reformer reaction chamber and at the point where it communicates with the reformed gas manifold, and a hot air outlet is provided at the outside of the reformer reaction chamber and at the point where it communicates with the hot air manifold. The outer upper layer is arranged from the inside to the outside along the flue gas discharge direction, with the fuel gas preheater chamber and the evaporator chamber arranged sequentially. The fuel gas preheater chamber is equipped with a fuel gas inlet, and the evaporator chamber is equipped with a pure water inlet. After the outlets of the fuel gas and water vapor chambers merge, they are mixed through a three-way valve and then enter the mixed gas distribution chamber along the mixed gas channel.

[0005] Preferably, a high-temperature flue gas passage is provided between the air preheater chamber and the tail burner combustion chamber. Its bottom end is connected to the tail burner combustion chamber, and its top end is connected to the flue gas diversion passage on one of the two porous partition plates. This passage is used to transport the high-temperature flue gas generated by the combustion in the tail burner combustion chamber to the air preheater chamber and then to the fuel gas preheater chamber and the evaporator chamber, and finally discharge it.

[0006] Preferably, the bottom surface of the tail burner combustion chamber is provided with a combustion air adjustment hole and a fuel adjustment hole, respectively. A combustion air diversion chamber is provided at the bottom of the tail burner combustion chamber and at the position corresponding to the combustion air adjustment hole. A fuel diversion chamber is provided at the bottom of the tail burner combustion chamber and at the position corresponding to the fuel adjustment hole. The fuel gas inlet is connected to the fuel diversion chamber, and the combustion air inlet is connected to the combustion air diversion chamber. A combustion air diversion adjustment channel is provided on the outer wall of the tail burner combustion chamber in the area between it and the outer insulation shell. A combustion air adjustment hole connected to the combustion air diversion adjustment channel is provided on the inner wall of the tail burner combustion chamber for adjusting the flame shape. The combustion air diversion adjustment channel is connected to the combustion air diversion chamber.

[0007] Preferably, the mixed gas splitting chamber is connected to the reforming chamber through the mixed gas splitting hole on the porous partition plate 2, and the reforming chamber is connected to the reforming gas merging chamber at its bottom through the reforming gas splitting hole on the porous partition plate 2, for collecting and exporting the gas after the reforming reaction.

[0008] Preferably, the flow channels of the fuel gas preheater cavity and the evaporator cavity are both in the form of stainless steel coils, which are coiled and arranged in the high-temperature flue gas discharge channel on the outer upper layer. The fuel gas preheater cavity and the evaporator cavity are separated by perforated stainless steel partitions for rectifying the gas.

[0009] Preferably, the air preheater cavity, fuel gas preheater cavity, evaporator cavity, reformer reaction cavity, and tail burner combustion cavity are all enclosed by stainless steel inner walls and covered with an insulated outer shell.

[0010] Preferably, the tail burner combustion chamber burns SOFC anode tail gas to generate high-temperature flue gas of 800-1000℃, the air is preheated to 800-850℃ in the air preheater chamber, the reforming reaction temperature in the reformer reaction chamber is about 700℃, the fuel gas is preheated to 300-500℃ in the fuel gas preheater chamber, and the pure water is heated to 300-350℃ steam in the evaporator chamber.

[0011] Preferably, the tail burner combustion chamber, air preheater chamber, reformer reaction chamber, fuel gas preheater chamber, and evaporator chamber are integrated into a modular whole, which can be combined and configured according to power requirements.

[0012] Compared with the prior art, the beneficial effects of the present invention are: 1. Significantly improved thermal efficiency: Through multi-component integration and energy cascade utilization, the exhaust gas combustion energy recovery rate is increased to over 95%, the SOFC system power generation efficiency exceeds 65%, and the combined heat and power efficiency exceeds 90%, which is 10-15 percentage points higher than the traditional split system (total efficiency ≤80%). 2. Compact structure and flexible layout: The integrated design reduces the system size by 50%-60%, and the modular layout supports flexible expansion of power from 5-500kW, adapting to different distributed needs such as small residential spaces, medium power in industrial parks, and mobile ship scenarios. The installation cycle is shortened by 40%, and the operation and maintenance cost is reduced by 30%. 3. Excellent economic and environmental performance: Reduces the number of purchased components such as pipes and valves, and eliminates the temperature box, reducing system integration costs by more than 25%; at the same time, efficient energy utilization reduces fuel consumption, which is in line with the "dual carbon" target and the development trend of energy-efficient energy technology. Attached Figure Description

[0013] Figure 1 This is a schematic cross-sectional view of the overall layout of the cavities in this invention; Figure 2 This is a schematic diagram of the external three-dimensional structure of the present invention; Figure 3 This is a schematic cross-sectional view of the connection between the fuel gas preheater chamber and the evaporator chamber of the present invention; Figure 4This is a cross-sectional view of the connection between the air preheater chamber and the reformer reaction chamber of the present invention. Figure 5 This is a cross-sectional view of the combustion chamber of the tail burner of the present invention; Figure 6 This is a schematic diagram of the medium flow of the present invention.

[0014] In the picture: 1. Combustion chamber of the tailrace burner; 101. Ignition detector; 102. Anode tail gas inlet; 103. Fuel gas inlet; 104. Combustion air inlet; 105. Cathode tail gas inlet; 106. Combustion air adjustment port; 107. Fuel adjustment port; 108. Combustion air distribution chamber; 109. Fuel distribution chamber; 110. Combustion air distribution adjustment channel; 111. Combustion air adjustment port; 2. Air preheater cavity; 201. Air buffer zone; 202. Air heat exchange zone; 203. Air inlet; 204. Air distribution cavity; 205. Air distribution channel; 206. Porous partition plate one; 207. Air distribution hole; 208. Flue gas distribution channel; 209. High-temperature flue gas channel; 3. Reformer reaction chamber; 301. Hot air manifold; 302. Reformed gas manifold; 303. Mixed gas splitting chamber; 304. Reforming chamber; 305. Porous partition plate II; 306. Reformed gas outlet; 307. Hot air outlet; 308. Mixed gas splitting orifice; 309. Reformed gas splitting orifice 4. Fuel gas preheater chamber; 401. Fuel gas inlet; 5. Evaporator chamber; 501. Pure water inlet; 6. Tee; 7. Mixing gas passage; 8. Stainless steel partition. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0016] The following reference Figures 1-6 This application describes a multifunctional, high-efficiency, and energy-saving SOFC exhaust gas burner provided in one embodiment.

[0017] A multifunctional, high-efficiency, and energy-saving SOFC tail burner has an overall external heat-insulating shell, and each internal functional chamber is enclosed by a stainless steel inner wall.

[0018] The tail gas combustion chamber 1 is located in the lower part of the internal central layer, and its bottom is equipped with an anode tail gas inlet 102, a fuel gas inlet 103, a combustion air inlet 104, and a cathode tail gas inlet 105. An ignition detector 101 is installed inside the chamber. During operation, the unreacted tail gas discharged from the anode of the solid oxide fuel cell stack mixes and combusts with the supplementary fuel gas, combustion air, and cathode tail gas into the tail gas combustion chamber 1, producing high-temperature flue gas of 800 to 1000 degrees Celsius. The combustion air is distributed through the combustion air distribution chamber 108 and the combustion air distribution adjustment channel 110, and the intake air volume is adjusted through the combustion air adjustment hole 111 to control the flame pattern.

[0019] The air preheater chamber 2 is located in the upper part of the internal central layer, directly above the tail burner combustion chamber 1. Air enters through the air inlet 203, passes through the air distribution chamber 204, and is evenly distributed to the air buffer zone 201 through the air distribution holes 207. A porous partition plate 206 is provided between the air buffer zone 201 and the air heat exchange zone 202 to rectify the airflow. Air passes through the porous partition plate 206 into the air heat exchange zone 202, where it exchanges heat with the high-temperature flue gas rising through the high-temperature flue gas channel 209 in the tail burner combustion chamber 1. After being preheated to 800 to 850 degrees Celsius, it is discharged through the hot air manifold 301.

[0020] The reformer reaction chamber 3 is nested in the lower outer periphery of the tail burner combustion chamber 1. The reformer reaction chamber 3 consists of a bottom hot air manifold 301 and a reformed gas manifold 302, a top mixed gas splitting chamber 303, and a middle reforming chamber 304. The reforming chamber 304 is filled with a catalyst, and porous partition plates 305 are provided at its upper and lower ends. A reformed gas outlet 306 is provided on the outside of the reformer reaction chamber 3 and in communication with the reformed gas manifold 302, and a hot air outlet 307 is provided on the outside of the reformer reaction chamber 3 and in communication with the hot air manifold 301. The preheated fuel gas and water vapor are mixed through the three-way valve 6 and then enter the mixed gas distribution chamber 303. The mixture is then evenly introduced into the reforming chamber 304 through the mixed gas distribution hole 308. The methane water vapor reforming reaction occurs at a temperature of about 700 degrees Celsius. The reaction products are collected through the reforming gas distribution hole 309 and then discharged through the reforming gas manifold 302 and the reforming gas outlet 306.

[0021] The fuel gas preheater chamber 4 and evaporator chamber 5 are arranged on the upper outer perimeter, with the flow channels in the form of stainless steel coils coiled within the high-temperature flue gas passage. A perforated stainless steel partition 8 separates the fuel gas preheater chamber 4 and evaporator chamber 5 for rectifying the gas flow. Fuel gas enters the coil through fuel gas inlet 401 and is preheated to 300-500 degrees Celsius; pure water enters the coil through pure water inlet 501 and is heated to 300-3250 degrees Celsius steam. After the two fluids merge, they are mixed through a three-way valve 6 and enter the mixed gas distribution chamber 303 at the top of the reformer reaction chamber 3.

[0022] High-temperature flue gas rises from the tail burner combustion chamber 1, first flows through the air heat exchange zone 202 and exchanges heat with the air through the high-temperature flue gas channel 209, and then exchanges heat with the reformer reaction chamber 3, the fuel gas preheater coil and the evaporator coil in sequence, so as to realize the energy cascade utilization before being discharged.

[0023] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0024] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A multifunctional, high-efficiency, and energy-saving SOFC exhaust gas burner, characterized in that: Centered on the tail burner combustion chamber (1), a center-periphery layered integrated structure is adopted to integrate the tail burner combustion chamber (1), air preheater chamber (2), reformer reaction chamber (3), fuel gas preheater chamber (4), and evaporator chamber (5) into the same structural unit, with an external heat-insulating shell. The lower part of the internal central layer is provided with a tail burner combustion chamber (1), which is equipped with an ignition detector (101). The bottom is provided with an anode tail gas inlet (102), a fuel gas inlet (103), a combustion air inlet (104) and a cathode tail gas inlet (105). An air preheater cavity (2) is set in the upper part of the internal central layer. The upper part of the cavity is an air buffer zone (201). The air buffer zone (201) is the area between two porous partition plates (206). Both porous partition plates (206) are provided with air diversion holes (207) and flue gas diversion channels (208). The lower part is an air heat exchange zone (202). An air inlet (203) is provided on one side. After the air enters the air inlet (203), it is evenly distributed through the air diversion cavity (204) and then enters the air buffer zone (201). Then, it enters the air heat exchange zone (202) through the air diversion hole (207) at the bottom of the air buffer zone (201). The preheated hot air flows through the reformer reaction cavity (3) through the air diversion channel (205) and then enters the hot air confluence cavity (301) and is discharged through the hot air outlet (307). The lower outer layer is nested with a reformer reaction chamber (3), located outside the combustion chamber (1) of the tail burner. The reformer reaction chamber (3) consists of a bottom hot air manifold (301) and a reformed gas manifold (302), a top mixed gas splitting chamber (303), and a middle reforming chamber (304). The reforming chamber (304) is filled with a catalyst, and porous partition plates (305) are provided at its upper and lower ends. A reformed gas outlet (306) is provided at the outside of the reformer reaction chamber (3) and at the point where it connects with the reformed gas manifold (302), and a hot air outlet (307) is provided at the outside of the reformer reaction chamber (3) and at the point where it connects with the hot air manifold (301). The outer upper layer is arranged from the inside to the outside along the flue gas discharge direction, with the fuel gas preheater chamber (4) and the evaporator chamber (5) arranged sequentially. The fuel gas preheater chamber (4) is provided with a fuel gas inlet (401), and the evaporator chamber (5) is provided with a pure water inlet (501). After the outlets of the fuel gas and water vapor chambers merge, they are mixed through a three-way valve (6) and then enter the mixed gas diversion chamber (303) along the mixed gas channel (7).

2. The multifunctional, high-efficiency, and energy-saving SOFC exhaust gas burner according to claim 1, characterized in that: A high-temperature flue gas passage (209) is provided between the air preheater chamber (2) and the tail burner combustion chamber (1). Its bottom end is connected to the tail burner combustion chamber (1), and its top end is connected to the flue gas diversion passage (208) on the two porous partition plates (206). It is used to transport the high-temperature flue gas generated by the combustion in the tail burner combustion chamber (1) to the air preheater chamber (2) and then to the fuel gas preheater chamber (4) and the evaporator chamber (5), and finally discharge it.

3. The multifunctional, high-efficiency, and energy-saving SOFC exhaust gas burner according to claim 1, characterized in that: The bottom surface of the tail burner combustion chamber (1) is provided with an air-supporting air adjustment hole (106) and a fuel adjustment hole (107). An air-supporting air diversion chamber (108) is located at the bottom of the tail burner combustion chamber (1) and corresponding to the air-supporting air adjustment hole (106). A fuel diversion chamber (109) is located at the bottom of the tail burner combustion chamber (1) and corresponding to the fuel adjustment hole (107). The fuel gas inlet (103) is connected to the fuel diversion chamber (109). The combustion air inlet (104) is connected to the combustion air distribution chamber (108). The outer wall of the tail burner combustion chamber (1) and the area between it and the outer heat insulation shell are provided with a combustion air distribution adjustment channel (110). The inner wall of the tail burner combustion chamber (1) is provided with a combustion air adjustment hole (111) connected to the combustion air distribution adjustment channel (110) for adjusting the flame shape. The combustion air distribution adjustment channel (110) is connected to the combustion air distribution chamber (108).

4. The multifunctional, high-efficiency, and energy-saving SOFC exhaust gas burner according to claim 1, characterized in that: The mixed gas splitting chamber (303) is connected to the reforming chamber (304) through the mixed gas splitting hole (308) on the porous partition plate II (305). The reforming chamber (304) is connected to the reforming gas collection chamber (302) at its bottom through the reforming gas splitting hole (309) on the porous partition plate II (305), which is used to collect and export the gas after the reforming reaction.

5. The multifunctional, high-efficiency, and energy-saving SOFC exhaust gas burner according to claim 1, characterized in that: The flow channels of the fuel gas preheater chamber (4) and the evaporator chamber (5) are both made of stainless steel coils, which are coiled and arranged in the high-temperature flue gas discharge channel on the outer upper layer. The fuel gas preheater chamber (4) and the evaporator chamber (5) are separated by perforated stainless steel partitions (8) for rectifying the gas.

6. The multifunctional, high-efficiency, and energy-saving SOFC exhaust gas burner according to claim 1, characterized in that: The air preheater chamber (2), fuel gas preheater chamber (4), evaporator chamber (5), reformer reaction chamber (3), and tail burner combustion chamber (1) are all enclosed by stainless steel inner walls and covered with an insulated outer shell.

7. The multifunctional, high-efficiency, and energy-saving SOFC exhaust gas burner according to claim 1, characterized in that: The tail burner combustion chamber (1) burns SOFC anode tail gas to generate high-temperature flue gas of 800-1000℃. The air is preheated to 800-850℃ in the air preheater chamber (2). The reforming reaction temperature in the reformer reaction chamber (3) is about 700℃. The fuel gas is preheated to 300-500℃ in the fuel gas preheater chamber (4). The pure water is heated to 300-350℃ steam in the evaporator chamber (5).

8. The multifunctional, high-efficiency, and energy-saving SOFC exhaust gas burner according to claim 1, characterized in that: The tail burner combustion chamber (1), air preheater chamber (2), reformer reaction chamber (3), fuel gas preheater chamber (4), and evaporator chamber (5) are integrated into a modular whole and can be combined and configured according to power requirements.

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