Gas catalytic oxidation safety burner

Abstract

The application discloses a gas catalytic oxidation safe combustor, and comprises a shell, a heat insulator, a catalytic heat accumulator, a silicon carbide layer and an igniter. The shell is provided with an air inlet and an air outlet. The heat insulator is arranged in the shell and is provided with a plurality of through holes. The diameter of the through holes is smaller than the quenching diameter of the gas flame. The catalytic heat accumulator is arranged in the shell and is located on the side of the heat insulator facing the air outlet. The catalytic heat accumulator is a porous heat storage structure, and the surface of the catalytic heat accumulator is coated with a methane oxidation catalyst. The silicon carbide layer is arranged in the shell and is located on the side of the catalytic heat accumulator facing the air outlet. The igniter is arranged at the silicon carbide layer and is used for igniting the gas. After the gas flows into the shell through the air inlet, the gas flows through the heat insulator, the catalytic heat accumulator and the silicon carbide layer in sequence, is ignited by the igniter, and then burns in the internal pores and the surface of the silicon carbide layer. The application realizes the safe, stable and continuous combustion of low-concentration gas and widens the concentration range of the available gas.

Description

Technical Field

[0001] This invention belongs to the field of gas protection technology, specifically relating to a gas catalytic oxidation safety burner. Background Technology

[0002] Methane gas is a major by-product of coal mining, with low-concentration methane (methane volume fraction below 8%) being emitted in enormous quantities. As a potent greenhouse gas, direct emission of methane not only wastes clean energy but also has significant negative impacts on the ecological environment. Therefore, the resource utilization and harmless treatment of low-concentration methane are of great importance. Combustion is one of the main treatment pathways for low-concentration methane; however, the methane concentration in low-concentration methane is close to the lower explosive limit, resulting in poor combustion stability and a tendency for flameout and flameout. Simultaneously, the flame can easily propagate back along the airflow channel to the intake side, causing backfire or even explosions. Among existing burners, metal fiber burners are only suitable for methane with a methane volume fraction of 5% or higher, and cannot handle methane in lower concentration ranges. Honeycomb ceramic burners and diffusion burners also struggle to simultaneously meet the requirements of backfire prevention and stable combustion when treating low-concentration methane. Summary of the Invention

[0003] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, embodiments of this invention propose a gas catalytic oxidation safety burner that achieves safe, stable, and continuous combustion of low-concentration gas and broadens the range of usable gas concentrations.

[0004] The gas catalytic oxidation safety burner of this invention includes a housing with an inlet and an outlet; a heat insulator disposed within the housing, the heat insulator having multiple through holes, the diameter of which is smaller than the quenching diameter of the gas flame; a catalytic heat storage body disposed within the housing and located on the side of the heat insulator facing the outlet, the catalytic heat storage body having a porous heat storage structure and its surface coated with a methane oxidation catalyst; a silicon carbide layer disposed within the housing and located on the side of the catalytic heat storage body facing the outlet; and an igniter disposed at the silicon carbide layer for igniting the gas; wherein, after the gas flows into the housing through the inlet, it flows sequentially through the heat insulator, the catalytic heat storage body, and the silicon carbide layer, and after being ignited by the igniter, a combustion reaction occurs in the internal pores and surface of the silicon carbide layer.

[0005] This invention achieves safe, stable, and continuous combustion of low-concentration methane through the synergistic combination of heat insulation through-hole quenching to prevent backfire, catalytic low-temperature oxidation and stable combustion of the catalytic heat storage body, and high-temperature heat storage combustion of the silicon carbide layer, and also broadens the range of usable methane concentrations.

[0006] Preferably, the gas catalytic oxidation safety burner further includes a flame arrester, which is connected upstream of the air inlet and in series in the gas delivery pipeline to prevent backfire from spreading to the gas delivery pipeline.

[0007] Preferably, the gas catalytic oxidation safety burner further includes an airflow distribution plate, which is disposed inside the housing and located on the side of the heat insulator facing the air inlet; the airflow distribution plate has non-uniformly arranged airflow holes to make the gas flow uniformly distributed in the central and edge regions of the housing cross-section.

[0008] Preferably, a preset gap is left between the airflow distribution plate and the heat insulator, and between the heat insulator and the catalytic heat storage body; the catalytic heat storage body and the silicon carbide layer are fitted together.

[0009] Preferably, the heat insulator is a plate, and the through hole extends along the airflow direction and penetrates the plate, so that the backfire can be quenched in the through hole to prevent the backfire from spreading to the air intake side.

[0010] Preferably, the methane oxidation catalyst is used to lower the ignition temperature of the methane oxidation reaction, so that some of the methane undergoes a low-temperature oxidation reaction on the surface of the catalytic heat storage body, and the heat released by the reaction is transferred to the silicon carbide layer by the gas flow.

[0011] Preferably, the catalytic heat storage body has a honeycomb porous structure or a particle-stacking porous structure.

[0012] Preferably, the silicon carbide layer has a porous silicon carbide structure, and the heat generated by the combustion reaction is transferred back to the catalytic heat storage body through thermal radiation and thermal conduction to preheat the catalytic heat storage body.

[0013] Preferably, the gas catalytic oxidation safety burner further includes a flame probe, which is disposed on the side of the silicon carbide layer facing the gas outlet, for detecting the working status of the combustion flame.

[0014] Preferably, the gas catalytic oxidation safety burner further includes a temperature sensor, the detection end of which is inserted inside the catalytic heat storage body and / or the silicon carbide layer, for detecting the temperature state inside the burner.

[0015] In this embodiment of the gas catalytic oxidation safety burner, the gas flows into the shell through the inlet and then sequentially passes through the heat insulator, the catalytic heat storage body, and the silicon carbide layer. After being ignited by the igniter, the gas undergoes a combustion reaction in the internal pores and surface of the silicon carbide layer. On one hand, the heat insulator has multiple through holes with a diameter smaller than the quenching diameter of the gas flame. The reflected flame enters these through holes and is quenched by heat dissipation from the hole walls, reliably preventing backfire from spreading to the inlet side and ensuring the safety of the combustion process. On the other hand, the surface of the catalytic heat storage body is coated with a methane oxidation catalyst, which lowers the ignition temperature of the methane oxidation reaction, allowing some methane to undergo low-temperature oxidation and exothermic reactions on its surface. Combined with the heat storage effect of the porous heat storage structure, combustion can continue even when the gas concentration fluctuates, especially when the concentration decreases, preventing flameout and thus lowering the lower limit of the combustible gas concentration, broadening the burner's applicable concentration range. Finally, the silicon carbide layer serves as a high-temperature resistant porous combustion carrier, where the combustion reaction takes place in its internal pores and on its surface. The combustion zone exhibits uniform temperature distribution and good combustion stability. Furthermore, the combustion heat can be transferred back to the preheating catalytic heat storage body through thermal radiation and thermal conduction, forming a self-sustaining stable combustion state. Attached Figure Description

[0016] Figure 1 This is an overall schematic diagram of the present invention.

[0017] Figure label: 1. Housing; 11. Air inlet; 12. Air outlet; 13. Air inlet section; 2. Heat insulator; 21. Through hole; 3. Catalytic regenerator; 4. Silicon carbide layer; 5. Igniter; 6. Flame arrester; 7. Airflow distribution plate; 71. Airflow hole; 8. Flame probe; 9. Temperature sensor. Detailed Implementation

[0018] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0019] like Figure 1As shown, the gas catalytic oxidation safety burner of this embodiment includes a shell 1, a heat insulator 2, a catalytic heat storage body 3, a silicon carbide layer 4, and an igniter 5. The shell 1 has an air inlet 11 and an air outlet 12. The heat insulator 2 is located inside the shell 1 and has multiple through holes 21, the diameter of which is smaller than the quenching diameter of the gas flame. The catalytic heat storage body 3 is located inside the shell 1 and on the side of the heat insulator 2 facing the air outlet 12. The catalytic heat storage body 3 has a porous heat storage structure, and its surface is coated with a methane oxidation catalyst. The silicon carbide layer 4 is located inside the shell 1 and on the side of the catalytic heat storage body 3 facing the air outlet 12. The igniter 5 is located at the silicon carbide layer 4 and is used to ignite the gas. Among them, the gas flows into the shell 1 through the air inlet 11, and then flows through the heat insulator 2, the catalytic heat storage body 3 and the silicon carbide layer 4 in sequence. After being ignited by the igniter 5, the gas undergoes a combustion reaction in the internal pores and surface of the silicon carbide layer 4.

[0020] Through the above structural arrangement, the gas forms a flow channel within the casing 1, pointing from the inlet 11 to the outlet 12. The functional components are arranged sequentially along the airflow direction, resulting in a smooth flow path and compact structure. The aperture of the through-hole 21 in the heat insulator 2 is smaller than the quenching diameter of the gas flame, allowing it to be quenched when the flame propagates back towards the inlet side, thus preventing backfire. The catalytic regenerator 3 combines heat storage and catalytic functions, while the silicon carbide layer 4, acting as a combustion carrier, can withstand the high temperatures generated by the combustion reaction. The combustion reaction occurs within the pores and surface of the silicon carbide layer 4, resulting in good combustion stability and facilitating the safe and stable combustion of low-concentration gas.

[0021] In some specific embodiments, the housing 1 has a cylindrical structure, with the air inlet 11 located at the upstream end of the housing 1 along the airflow direction, and the air outlet 12 located at the downstream end of the housing 1 along the airflow direction. Optionally, the housing 1 is made of metal; for example, the housing 1 can be made of stainless steel to balance structural strength and high-temperature resistance. Furthermore, the inner wall of the housing 1 is lined with an insulation layer to reduce heat loss from the burner, thus helping to maintain the internal temperature level of the burner. For example, the insulation layer can be made of high-temperature resistant insulating materials such as ceramic fiber or aluminum silicate fiber.

[0022] In some specific embodiments, the inner diameter of the housing 1 gradually increases along the direction from the air inlet 11 toward the heat insulator 2, forming an air inlet section 13. The air inlet section 13 can reduce the airflow velocity and buffer the airflow, so that the gas airflow entering the housing 1 is initially homogenized. Furthermore, the diameter of the air inlet 11 is small, which facilitates connection with the external gas delivery pipeline; the diameter of the air outlet 12 is the same as the diameter of the housing 1, that is, the end of the housing 1 facing the air outlet 12 is open, so that the flue gas after combustion can be discharged smoothly.

[0023] In some specific embodiments, the gas is a low-concentration gas, which refers to gas with a methane volume fraction of less than 8%. Further, the low-concentration gas can also refer to gas with a methane volume fraction of less than 5%. The gas catalytic oxidation safety burner of this embodiment can still achieve stable combustion for this type of low-concentration gas.

[0024] In some specific embodiments, the heat insulator 2 is made of lightweight insulating material, which reduces the heat transfer from the catalytic regenerator 3 and the silicon carbide layer 4 to the intake side while allowing gas to pass through. It should be noted that the quenching diameter refers to the minimum channel size within which the flame can sustain propagation. When the channel aperture is smaller than the quenching diameter, the flame is extinguished due to heat dissipation from the channel wall. Multiple through holes 21 are distributed on the heat insulator 2 to allow gas to pass through evenly.

[0025] In some specific embodiments, the catalytic heat storage body 3 is made of a porous material with heat storage capacity. The porous heat storage structure can provide a large gas-solid contact area and can absorb and store heat. The methane oxidation catalyst is coated on the surface of the catalytic heat storage body 3. As an example, the slurry containing the methane oxidation catalyst can be coated on the surface of the catalytic heat storage body 3 by impregnation coating, and then cured after drying and calcination.

[0026] In some specific embodiments, the silicon carbide layer 4 is made of silicon carbide. Silicon carbide has high refractoriness and good thermal conductivity, enabling it to withstand the high temperatures generated by the combustion reaction for a long time. The internal pores of the silicon carbide layer 4 provide a flow channel and combustion space for the gas, and the methane and oxygen in the gas undergo premixed combustion in the internal pores and on the surface of the silicon carbide layer 4.

[0027] In some specific embodiments, the igniter 5 is an electric igniter 5. For example, the igniter 5 can be an ignition needle or a glow plug. The igniter 5 is located at the silicon carbide layer 4. The electric spark or high-temperature hot spot generated by the igniter 5 can ignite the gas flowing through the silicon carbide layer 4. When the burner is started, the gas is first introduced, and then the igniter 5 is controlled to ignite. After the combustion is stable, the igniter 5 stops working.

[0028] Combination Figure 1 The working process of the gas catalytic oxidation safety burner in this embodiment is explained as shown. Gas flows into the housing 1 through the inlet 11, is buffered and homogenized by the inlet section 13, and then passes through the through hole 21 of the heat insulator 2; it then flows through the catalytic heat storage body 3, where some methane undergoes a low-temperature oxidation reaction under the action of the methane oxidation catalyst and releases heat; the gas continues to flow into the silicon carbide layer 4, and after being ignited by the igniter 5, a combustion reaction occurs in the internal pores and surface of the silicon carbide layer 4, and the high-temperature flue gas generated by the combustion is discharged through the outlet 12.

[0029] In some embodiments, see Figure 1 As shown, the gas catalytic oxidation safety burner also includes a flame arrester 6, which is connected to the upstream side of the air inlet 11 and connected in series in the gas delivery pipeline to prevent backfire from spreading to the gas delivery pipeline.

[0030] Through the above coordination, the flame arrester 6 serves as the last safety barrier for the burner. When the anti-backfire measures inside the burner fail and the flame propagates back to the air inlet 11, the flame arrester 6 can block the flame outside the gas delivery pipeline, preventing the flame from spreading along the gas delivery pipeline, which helps to ensure the safety of the gas delivery pipeline and the upstream gas source.

[0031] In some specific embodiments, the flame arrester 6 is a pipeline-type flame arrester 6. The pipeline-type flame arrester 6 is connected in series in the gas delivery pipeline, offering convenient installation and good versatility. Further, the pipeline-type flame arrester 6 includes a flame-arresting housing 1 and a flame-arresting core disposed within the flame-arresting housing 1. The flame-arresting core has small gas channels; when a flame enters the gas channels, it is extinguished by heat dissipation from the wall surface. As an example, the flame-arresting core can be a corrugated plate flame-arresting core, a metal mesh flame-arresting core, or a porous metal flame-arresting core.

[0032] In some specific embodiments, the flame arrester 6 is positioned close to the air inlet 11, and the flame arrester 6 and the air inlet 11 can be connected by a flange or a threaded connection. The air inlet 11 has a small diameter, which facilitates connection and matching with the flame arrester 6 and the gas delivery pipeline.

[0033] In some embodiments, see Figure 1 As shown, the gas catalytic oxidation safety burner also includes an airflow distribution plate 7, which is located inside the housing 1 and on the side of the heat insulator 2 facing the air inlet 11. The airflow distribution plate 7 has non-uniformly arranged airflow holes 71, which are used to make the gas flow uniformly distributed in the central and edge areas of the cross-section of the housing 1.

[0034] The gas flow entering through the air inlet 11 typically has a higher velocity in the central region of the cross-section of the shell 1 and a lower velocity in the edge region. The airflow distribution plate 7 redistributes the airflow through non-uniformly arranged airflow holes 71, so that the gas flow is evenly distributed in the central and edge regions, which is beneficial to the uniform and stable combustion reaction in the silicon carbide layer 4.

[0035] In some specific embodiments, the number of airflow holes 71 on the airflow distribution plate 7 is smaller in the central region and larger in the edge region. By increasing the airflow capacity in the edge region and restricting the airflow capacity in the central region, the airflow tends to be uniform across the cross-section of the housing 1. In other specific embodiments, the diameter of the airflow holes 71 in the central region of the airflow distribution plate 7 is smaller, and the diameter of the airflow holes 71 in the edge region is larger, which can also achieve uniform distribution of airflow in the central and edge regions. Optionally, the above two methods can also be used in combination, that is, fewer airflow holes 71 and smaller diameter in the central region, and more airflow holes 71 and larger diameter in the edge region.

[0036] In some specific embodiments, the airflow distribution plate 7 is a circular plate, and its outer edge is connected to the inner wall of the housing 1. As an example, it can be installed inside the housing 1 by welding, snap-fitting, or screw connection. The airflow distribution plate 7 can be made of stainless steel plate or ceramic plate. Furthermore, the airflow distribution plate 7 works together with the air intake section 13 of the housing 1. The air intake section 13 performs preliminary buffering and homogenization of the airflow, while the airflow distribution plate 7 performs secondary distribution of the airflow, resulting in a better airflow homogenization effect.

[0037] In some embodiments, a preset gap is left between the airflow distribution plate 7 and the heat insulator 2, and between the heat insulator 2 and the catalytic heat storage body 3; the catalytic heat storage body 3 and the silicon carbide layer 4 are attached to each other.

[0038] Through the above-mentioned coordination, the preset gap between the airflow distribution plate 7 and the heat insulator 2 can buffer the airflow, allowing the airflow to be further homogenized and evenly distributed before flowing through the heat insulator 2; the preset gap between the heat insulator 2 and the catalytic heat storage body 3 can reduce the thermal stress between the two and provide buffer space for the airflow. The catalytic heat storage body 3 and the silicon carbide layer 4 are closely fitted together, and the thermal resistance between the two is small, which is conducive to the efficient return of combustion heat to the catalytic heat storage body 3.

[0039] In some specific embodiments, the size of the preset gap can be set according to the specifications of the burner. For example, the preset gap can be 5 mm to 30 mm. In some specific embodiments, the catalytic heat storage body 3 and the silicon carbide layer 4 are in direct contact. Alternatively, a high-temperature resistant transition pad can be sandwiched between the catalytic heat storage body 3 and the silicon carbide layer 4 to fill the microscopic unevenness of the contact surface and further reduce the contact thermal resistance.

[0040] In some embodiments, the heat insulator 2 is a plate, and the through hole 21 extends along the airflow direction and penetrates the plate. The backfire can be quenched in the through hole 21 to prevent the backfire from spreading to the air intake side.

[0041] With the above-mentioned combination, the heat insulator 2 of the plate structure is easy to process and install. The through hole 21 penetrates the plate along the airflow direction, forming a slender quenching channel. After the backflowing flame enters the through hole 21, it is rapidly cooled down due to the heat dissipation effect of the hole wall and quenched in the through hole 21, thereby preventing the backfire from spreading to the air intake side.

[0042] In some specific embodiments, the heat insulator 2 is a lightweight heat insulation board with ultra-fine pores. As an example, the heat insulator 2 can be made of porous ceramic plate, ceramic fiber plate or microporous heat insulation board. The pore diameter of the through hole 21 is smaller than the quenching diameter of the gas flame. As an example, the pore diameter of the through hole 21 can be 0.5 mm to 2 mm, and the specific pore diameter can be determined according to the concentration range of the gas.

[0043] In some specific embodiments, multiple through holes 21 are evenly arranged on the plate, and the plate surface is perpendicular to the airflow direction. The outer edge of the plate is connected to the inner wall of the housing 1. As an example, the plate can be embedded in the annular protrusion on the inner wall of the housing 1, or connected to the inner wall of the housing 1 by screws or buckles.

[0044] In some embodiments, the methane oxidation catalyst is used to lower the ignition temperature of the methane oxidation reaction, so that some methane undergoes a low-temperature oxidation reaction on the surface of the catalytic heat storage body 3, and the heat released by the reaction is transferred to the silicon carbide layer 4 by the gas flow.

[0045] Through the above-described combination, some methane can undergo oxidation and release heat at a relatively low temperature on the surface of the catalytic regenerator 3. The heat released by oxidation is transferred by the airflow and carried into the silicon carbide layer 4, supplementing the heat for the combustion reaction within the silicon carbide layer 4. When the concentration of methane fluctuates, especially when the concentration decreases, the heat supplemented by the low-temperature oxidation reaction helps to maintain the continuous combustion reaction within the silicon carbide layer 4, preventing flameout, thereby reducing the methane concentration required for combustion and broadening the range of methane concentrations that the burner can combust.

[0046] In some specific embodiments, the methane oxidation catalyst is a noble metal catalyst; for example, the methane oxidation catalyst can be a platinum catalyst, a palladium catalyst, or a platinum-palladium composite catalyst. In other specific embodiments, the methane oxidation catalyst can also be a non-noble metal catalyst; for example, the methane oxidation catalyst can be a perovskite catalyst or a hexaaluminate catalyst.

[0047] In some specific embodiments, the catalytic regenerator 3 absorbs and stores the heat returned from the combustion reaction, maintaining its own temperature above the ignition temperature of the methane oxidation catalyst, thus ensuring the continuous low-temperature oxidation reaction. The low-temperature oxidation reaction complements the combustion reaction within the silicon carbide layer 4, making the combustion process of low-concentration gas more stable.

[0048] In some embodiments, the catalytic heat storage body 3 has a honeycomb porous structure.

[0049] Through the above combination, the honeycomb porous structure has regular pores and low airflow resistance, allowing gas to pass through smoothly. In addition, the honeycomb porous structure has a large specific surface area, which is beneficial for coating the methane oxidation catalyst and ensuring sufficient contact between the gas and the catalyst.

[0050] In some specific embodiments, the honeycomb porous structure includes multiple channels that extend along the airflow direction, and the cross-sectional shape of the channels can be circular, square, or regular hexagonal. The honeycomb porous structure can be made of ceramic materials such as cordierite, mullite, or silicon carbide. A methane oxidation catalyst is coated on the inner wall surface of each channel.

[0051] In some embodiments, the catalytic heat storage body 3 has a porous structure with granular stacking.

[0052] Through the above combination, the granular porous structure has abundant pores and good heat storage capacity, and the filling and replacement of granules are convenient, resulting in low maintenance costs.

[0053] In some specific embodiments, the particle-stacking porous structure is formed by stacking multiple porous particles, with irregular pores between adjacent porous particles allowing airflow. As an example, the porous particles can be alumina ceramic particles or silicon carbide particles, and the particle size can be from 3 mm to 10 mm. A methane oxidation catalyst is coated on the surface of the porous particles.

[0054] In some embodiments, the silicon carbide layer 4 is a porous silicon carbide structure, and the heat generated by the combustion reaction is transferred back to the catalytic heat storage body 3 through thermal radiation and thermal conduction to preheat the catalytic heat storage body 3.

[0055] Through the above-described combination, the porous silicon carbide structure provides a large reaction area for the combustion reaction. Part of the heat generated by the combustion reaction is discharged with the flue gas, while the other part is transferred back to the catalytic regenerator 3 via thermal radiation and conduction, preheating the catalytic regenerator 3 and achieving heat recycling. The preheated catalytic regenerator 3 can maintain a low-temperature oxidation reaction on its surface. This low-temperature oxidation reaction and the combustion reaction within the silicon carbide layer 4 mutually promote each other, forming a self-sustaining stable combustion state.

[0056] In some specific embodiments, the porous silicon carbide structure can be foamed silicon carbide, honeycomb silicon carbide, or porous silicon carbide ceramic. Silicon carbide has high refractoriness and can withstand the high temperatures generated by the combustion reaction for a long time without deformation or burn-out. Furthermore, silicon carbide has good thermal conductivity and thermal radiation properties, which is beneficial for the return of combustion heat to the catalytic regenerator 3.

[0057] In some embodiments, the gas catalytic oxidation safety burner further includes a flame probe 8, which is disposed on the side of the silicon carbide layer 4 facing the gas outlet 12, and is used to detect the working status of the combustion flame.

[0058] With the above combination, the flame probe 8 is positioned directly on the gas outlet side of the combustion flame, enabling real-time detection of the combustion flame's operating status and timely detection of abnormalities such as flameout, which helps improve the safety of burner operation.

[0059] In some specific embodiments, the flame probe 8 is an ionization flame probe 8, with the detection end of the flame probe 8 positioned close to the surface of the silicon carbide layer 4 facing the outlet 12. Optionally, the flame probe 8 can also be an ultraviolet flame detector.

[0060] Furthermore, the flame probe 8 is signal-connected to an external controller. When the flame probe 8 detects a flameout, the external controller triggers an alarm signal or cuts off the gas supply. As an example, a shut-off valve is installed on the gas delivery pipeline, and the external controller is signal-connected to the shut-off valve. When the external controller receives a flameout signal, it controls the shut-off valve to close, thereby cutting off the gas supply and preventing the continuous discharge of unburned gas.

[0061] In some embodiments, the gas catalytic oxidation safety burner also includes a temperature sensor 9, the detection end of which is inserted inside the catalytic heat storage body 3 to detect the temperature state inside the burner.

[0062] With the above combination, the temperature sensor 9 is directly inserted into the interior of the catalytic heat storage body 3, and the detection data can accurately reflect the temperature level of the catalytic heat storage body 3, making it easy to determine whether the catalytic heat storage body 3 has reached the ignition temperature of the methane oxidation catalyst.

[0063] In some specific embodiments, the temperature sensor 9 is a thermocouple or a resistance temperature detector (RTD). The detection end of the temperature sensor 9 passes through the wall of the housing 1 from the outside and is inserted into the interior of the catalytic regenerator 3. Furthermore, the temperature sensor 9 is connected to an external controller. When the temperature sensor 9 detects an abnormal temperature condition, such as the temperature of the catalytic regenerator 3 falling below a preset temperature threshold, the external controller triggers an alarm signal or cuts off the gas supply.

[0064] In some embodiments, the detection end of the temperature sensor 9 is inserted inside the silicon carbide layer 4.

[0065] With the above combination, the temperature sensor 9 is directly inserted into the interior of the silicon carbide layer 4, which can detect the temperature status of the combustion zone in real time, making it easier to determine whether the combustion reaction is proceeding normally.

[0066] In some specific embodiments, the temperature sensor 9 is a thermocouple, with its sensing end inserted into the internal pores of the silicon carbide layer 4. Furthermore, the temperature sensor 9 is connected to an external controller. When the temperature of the silicon carbide layer 4 is detected to be higher than a safety threshold or lower than the normal operating temperature, the external controller triggers an alarm signal or cuts off the gas supply.

[0067] Optionally, in some specific embodiments, there are multiple temperature sensors 9, with the detection ends of the multiple temperature sensors 9 respectively inserted inside the catalytic heat storage body 3 and the silicon carbide layer 4, so as to simultaneously detect the temperature status of the catalytic heat storage body 3 and the silicon carbide layer 4, and to perform more comprehensive monitoring of the operating status of the burner.

[0068] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0069] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0070] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0071] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0072] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0073] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A gas catalytic oxidation safety burner, characterized in that, include: A housing, wherein the housing is provided with an air inlet and an air outlet; A heat insulator is disposed inside the housing, and the heat insulator has multiple through holes, the diameter of which is smaller than the quenching diameter of the gas flame; A catalytic heat storage body is disposed inside the shell and located on the side of the heat insulator facing the gas outlet. The catalytic heat storage body has a porous heat storage structure and its surface is coated with a methane oxidation catalyst. A silicon carbide layer is disposed inside the housing and located on the side of the catalytic heat storage body facing the gas outlet; An igniter, located at the silicon carbide layer, is used to ignite the gas. The gas flows into the housing through the air inlet and then flows sequentially through the heat insulator, the catalytic heat storage body and the silicon carbide layer. After being ignited by the igniter, it undergoes a combustion reaction in the internal pores and surface of the silicon carbide layer.

2. The gas catalytic oxidation safety burner according to claim 1, characterized in that, It also includes a flame arrester, which is connected upstream of the air inlet and connected in series in the gas delivery pipeline to prevent backfire from spreading to the gas delivery pipeline.

3. The gas catalytic oxidation safety burner according to claim 1 or 2, characterized in that, It also includes an airflow distribution plate, which is disposed inside the housing and located on the side of the heat insulator facing the air inlet; the airflow distribution plate has non-uniformly arranged airflow holes to make the gas flow uniformly distributed in the central and edge regions of the housing cross-section.

4. The gas catalytic oxidation safety burner according to claim 3, characterized in that, A preset gap is left between the airflow distribution plate and the heat insulator, and between the heat insulator and the catalytic heat storage body; the catalytic heat storage body and the silicon carbide layer are fitted together.

5. The gas catalytic oxidation safety burner according to claim 1, characterized in that, The heat insulator is a plate, and the through hole extends along the airflow direction and penetrates the plate. The backfire can be quenched in the through hole to prevent backfire from spreading to the intake side.

6. The gas catalytic oxidation safety burner according to claim 1, characterized in that, The methane oxidation catalyst is used to lower the ignition temperature of the methane oxidation reaction, so that some of the methane undergoes a low-temperature oxidation reaction on the surface of the catalytic heat storage body, and the heat released by the reaction is transferred to the silicon carbide layer by the gas flow.

7. The gas catalytic oxidation safety burner according to claim 1, characterized in that, The catalytic heat storage body has a honeycomb porous structure or a particle-stacking porous structure.

8. The gas catalytic oxidation safety burner according to claim 1, characterized in that, The silicon carbide layer has a porous silicon carbide structure. The heat generated by the combustion reaction is transferred back to the catalytic heat storage body through thermal radiation and thermal conduction to preheat the catalytic heat storage body.

9. The gas catalytic oxidation safety burner according to claim 1, characterized in that, It also includes a flame probe, which is located on the side of the silicon carbide layer facing the gas outlet, and is used to detect the working status of the combustion flame.

10. The gas catalytic oxidation safety burner according to claim 1, characterized in that, It also includes a temperature sensor, the detection end of which is inserted inside the catalytic regenerator and / or the silicon carbide layer, for detecting the temperature state inside the burner.

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