Combustor based on gas-solid fuel blending and control method

Abstract

The application discloses a combustor based on gas-solid fuel mixing and a regulation method, which comprises a nozzle and an ignition device; the nozzle comprises a hydrogen fuel supply area, an air supply area, a pulverized coal fuel supply area and a carbon dioxide regulation area; the hydrogen fuel supply area comprises a carbon dioxide passage, an accelerating device, a hydrogen passage, a gas-gas mixing pipe, a pressurizing structure, a pulverized coal side and an air side mixed gas nozzle; the air supply area comprises a hot air passage, an air shunting and pressurizing area, an air inlet and outlet grid and a supplementary air passage; the pulverized coal fuel supply area comprises an ejecting air passage, a pulverized coal passage, an air lock and a gas-solid mixing pipe; the carbon dioxide regulation area of the nozzle comprises a carbon dioxide regulation passage, a carbon dioxide angle regulator, a carbon dioxide coating pipeline, a carbon dioxide nozzle and a fuel nozzle; the ignition device comprises a linkage rod, a condenser, a high-energy laser beam and a temperature sensor; the application is efficient and simple, and can realize quantitative mixing and stable combustion of hydrogen and pulverized coal.

Description

Technical Field

[0001] This invention relates to the field of burner technology, and more specifically to a burner and control method based on gas-solid fuel blending designed according to the fuel characteristics of pulverized coal and hydrogen. Background Technology

[0002] Hydrogen possesses immense potential and a wide range of applications due to its high calorific value, widespread availability, and pollution-free combustion products. In contrast, pulverized coal, widely used in coal-fired power plants, has drawbacks due to its non-renewable nature and the polluting nature of its combustion products. Therefore, research into combining clean fuels like hydrogen with traditional fuels remains of practical significance.

[0003] Due to the gaseous properties of hydrogen, it is impossible to effectively mix it with pulverized coal using traditional burner nozzles, which can even lead to imbalances in the ratio. Therefore, designing a rational and efficient burner configuration can effectively mix and burn hydrogen and pulverized coal. This mixing not only improves the pulverized coal burnout rate but also provides a suitable reducing atmosphere within the furnace, controlling pollutant generation, saving equipment and materials, protecting the environment, and reducing fossil fuel consumption, thereby achieving the goal of low-carbon emission reduction. Summary of the Invention

[0004] To address the limitation of traditional burner nozzles in effectively mixing hydrogen and pulverized coal, the present invention aims to provide a burner and control method based on gas-solid fuel blending. This burner and control method are highly efficient, environmentally friendly, and can achieve quantitative blending and stable combustion of hydrogen and pulverized coal.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A gas-solid fuel blending burner includes a nozzle 1 and an ignition device 2. The ignition device 2 is arranged above the nozzle 1 and, after being started, can irradiate the central area of ​​the fuel ejected from the nozzle 1 to ignite the fuel.

[0007] The nozzle 1 includes a gaseous fuel supply area, an air supply area, a pulverized coal fuel supply area, and a carbon dioxide regulating area. The gaseous fuel supply area and the air supply area are arranged at the nozzle inlet, with the air supply area above the gaseous fuel supply area, the pulverized coal fuel supply area on the upper side of the nozzle and close to the nozzle constriction throat nozzle, and the carbon dioxide regulating area at the nozzle constriction throat nozzle.

[0008] The gaseous fuel supply area includes a carbon dioxide passage 3, an acceleration device 4, a hydrogen passage 5, a gas-gas mixing pipe 6, a pressurization structure 7, a coal-powder side mixed gas nozzle 8, and an air-side mixed gas nozzle 9. The carbon dioxide passage 3 is connected to the acceleration device 4, which adopts a converging nozzle design. The hydrogen passage 5 is located in a converging section after the outlet of the acceleration device 4 and before the gas-gas mixing pipe 6. After the gas-gas mixing pipe 6 is a expanding section, and after the expanding section is the pressurization structure 7. The pressurization structure 7 is a converging and then expanding area formed by the inner and outer pipe walls. The pressurization structure 7 is divided into upper and lower parts, which are respectively connected to the coal-powder side mixed gas nozzle 8 and the air-side mixed gas nozzle 9. The shaft inside the nozzle cavity of the gaseous fuel supply area is connected to the left and right sides of the nozzle cavity, dividing the cavity into upper and lower areas. The hydrogen passage 5 drives the injection of low-pressure, low-speed hydrogen into the gas-gas mixing pipe 6, so that carbon dioxide and hydrogen are fully mixed to achieve the injection of hydrogen and carbon dioxide.

[0009] The air supply area includes a hot air passage 10, an air diversion and pressurization area 11, an air inlet grid 12, an air outlet grid 13, and a replenishment area 14. The air diversion and pressurization area 11 is located near the outlet of the air passage 10 and includes a concave surface extending inward from the inner wall of the nozzle near the outlet of the air passage 10, and a straight surface connecting the concave surface and the inner wall of the nozzle away from the outlet of the air passage 10. One end of the air inlet grid 12 is connected at the junction of the concave surface and the straight surface of the air diversion and pressurization area 11, and the other end is connected at the beginning of the gradually expanding section after the gas-gas mixing pipe 6. The air outlet grid 13 is located after the air diversion and pressurization area 11 and the air inlet grid 12. The area below the gas fuel supply area is the replenishment area 14.

[0010] The angle between the inner wall of the converging section of the acceleration device 4 and the axis is angle a, which is between 30° and 40°; the angle between the inner wall of the expanding section and the axis is angle b, which is between 5° and 15°; the angle between the inlet section of the gas-gas mixing pipe 6 and the axis is angle c, which is between 40° and 50°; the angle between the outlet section and the axis is angle d, which is between 15° and 25°; and the angle between the two inner wall surfaces of the pressurizing structure 7 is angle e, which is between 125° and 135°.

[0011] The pulverized coal fuel supply area includes an ejector air passage 15, a pulverized coal passage 16, an airlock 17, and a gas-solid mixing pipe 18. The air in the ejector air passage 15 passes through a converging region and its outlet is connected to the converging section before the gas-solid mixing pipe 18. The pulverized coal passage 16 is connected to the airlock 17 and is located on the side wall before the converging section of the gas-solid mixing pipe 18, forming a 90° angle with the ejector air passage 15. After the gas-solid mixing pipe 18, it is a gradually expanding and then converging pipe connected to the nozzle cavity.

[0012] The angle between the inner wall of the tapering section of the ejector air passage 15 and the axis is angle f, which is 15° to 25°; the angle between the inlet section of the gas-solid mixing pipe 18 and the axis is angle g, which is 50° to 60°; and the angle between the outlet section and the axis is angle h, which is 9° to 19°.

[0013] The carbon dioxide regulation zone includes a carbon dioxide regulation passage 19, a carbon dioxide angle adjuster 20, a carbon dioxide coated pipe 21, a carbon dioxide nozzle 22, and a fuel nozzle 23. The outlet of the carbon dioxide regulation passage 19 is divided into two paths. One path connects to the nozzle cavity through the carbon dioxide angle adjuster 20, which adjusts the airflow direction by changing the outlet angle. The other path connects to the carbon dioxide nozzle 22 through the carbon dioxide coated pipe 21. The carbon dioxide coated pipe 21 is a gradually expanding flow channel, which serves to pressurize the flow. The carbon dioxide coated pipe 21 and the carbon dioxide nozzle 22 cover the outside of the fuel nozzle 23, which helps to keep the throat temperature of the nozzle constant. The carbon dioxide nozzle 22 injects high-pressure carbon dioxide to suppress the impact of the shock wave generated by hydrogen deflagration on the combustion of pulverized coal, thereby preventing backfire and protecting the nozzle 23.

[0014] The ignition device includes a linkage 24, a condenser lens 25, a high-energy laser beam 26, and a temperature sensor 27. The linkage 24 is connected to the condenser lens 25 and can adjust the focusing position of the condenser lens 25. The high-energy laser beam 26 is focused by the condenser lens 25. After being focused, the high-energy laser beam 26 can provide sufficient energy to ignite the mixture of hydrogen and light coal powder gas over a long distance. The temperature sensor 27 detects the furnace temperature and automatically shuts off the high-energy laser beam 26 according to the furnace temperature.

[0015] The aforementioned method for controlling a combustor based on gas-solid fuel blending includes the following steps:

[0016] Step 1, Injection of hydrogen and carbon dioxide: The flow rate of carbon dioxide at the nozzle inlet is controlled through carbon dioxide passage 3. The carbon dioxide in carbon dioxide passage 3 is accelerated from subsonic to supersonic speed through acceleration device 4 to reach the injection conditions. Low-pressure, low-speed hydrogen from hydrogen passage 5 is injected into gas-gas mixing tube 6 in the constriction section before gas-gas mixing tube 6, so that carbon dioxide and hydrogen are fully mixed.

[0017] Step 2, Air Regulation: The hot air flow rate at the nozzle inlet is controlled through the hot air passage 10. The hot air at the outlet of the air passage 10 is divided into two paths after being turned by the concave surface of the air splitting and pressurization area 11. One stream of hot air flows through the air inlet grid plate 12, then through the air splitting and pressurization area to the air outlet grid plate 13, and then enters the nozzle cavity. The other stream of hot air passes through the outer wall of the air-to-air mixing pipe 6 to maintain a constant temperature, and then the airflow flows into the air replenishment passage 14.

[0018] Step 3, mixing of air and pulverized coal: The inlet air flow is controlled by the ejector air passage 15 to accelerate the air through the tapering area, and the pulverized coal airflow is ejected through the pulverized coal passage 16. The pulverized coal airflow passes through the airlock 17 to lock the air, making the pulverized coal entering the gas-solid mixing pipe 18 purer and removing impurities to achieve a better ejection effect. Under the action of air ejection, the pulverized coal and air enter the gas-solid mixing pipe 18 and are fully mixed to form a pulverized coal airflow. The pulverized coal airflow enters the nozzle cavity through the tapering nozzle of the gas-solid mixing pipe and is mixed once with the hot air flowing out of the air outlet grid plate 13 to form a pulverized coal airflow.

[0019] Step 4, gas-solid two-phase mixing: The hydrogen and carbon dioxide mixture from the gas-gas mixing pipe 6 is pressurized by the pressurizing structure 7. The pressurized mixed gas ejected from the coal powder side mixed gas nozzle 8 is mixed with hot air and the coal powder flow from the coal powder fuel supply area for a secondary mixing, so that the angle between the coal powder flow and the hydrogen and carbon dioxide mixed flow is 90°, so as to achieve the mixing effect of gaseous fuel and solid fuel and realize the effect of fuel richness separation; the pressurized mixed gas ejected from the air side mixed gas nozzle 9 is mixed with the hot air in the supplementary air passage 14, and the hot air in the supplementary air passage 14 provides oxygen supplementation for the mixed gas fuel; ensuring that the mixed gas fuel reacts vigorously with sufficient oxygen without competing with solid fuel for oxygen, so that both gaseous and solid fuels have sufficient oxygen for combustion and complete combustion;

[0020] Step 5, Carbon Dioxide Regulation: The carbon dioxide from the outlet of the carbon dioxide regulation passage 19 is divided into two paths. One path of carbon dioxide enters the nozzle cavity through the carbon dioxide angle regulator 20. By adjusting the direction of the carbon dioxide angle regulator 20, the direction of the mixed airflow is controlled so that the fuel can enter the nozzle constriction throat nozzle for normal combustion in the furnace. The other path of carbon dioxide passes through the carbon dioxide coating pipe 21 and the carbon dioxide nozzle 22. It is injected into the furnace through the carbon dioxide nozzle 22. The mixed fuel is injected into the furnace through the nozzle constriction throat and fuel nozzle 23. The carbon dioxide nozzle 22 sprays high-pressure carbon dioxide to suppress the impact of the shock wave generated by hydrogen deflagration on the combustion of pulverized coal, and at the same time, to prevent backfire and protect the fuel nozzle 23.

[0021] Step 6, ignition device activation: By adjusting the linkage rod 24, the irradiation angle of the condenser lens 25 is changed, so that the high-energy laser beam 26 releases a high-energy-density laser beam to ignite the hydrogen and light coal powder area to achieve the purpose of long-distance ignition; at the same time, after the temperature sensor 24 detects that the furnace temperature is stable, the high-energy laser beam 26 is automatically turned off, and then the condenser lens 25 is reset by the linkage rod 24.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] This invention designs a burner and control method based on the fuel characteristics of pulverized coal and hydrogen. It utilizes the property of carbon dioxide to suppress hydrogen deflagration and designs a nozzle configuration according to fuel characteristics to achieve effective mixing of air, pulverized coal, hydrogen, and carbon dioxide. This burner and control method can achieve effective mixing and stable combustion of pulverized coal and hydrogen fuels, and considers and suppresses the hazards caused by hydrogen combustion shock waves. This configuration is highly efficient, energy-saving, and environmentally friendly. Attached Figure Description

[0024] Figure 1 A simplified structural diagram of the burner arrangement.

[0025] Figure 2 A simplified diagram of the nozzle arrangement.

[0026] Figure 3 This is a simplified structural diagram of the ignition device. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. For example... Figure 1 As shown, a gas-solid fuel blending burner includes a nozzle 1 and an ignition device 2. The ignition device 2 is arranged above the nozzle 1 and, after being started, can irradiate the central area of ​​the fuel ejected from the nozzle 1 to ignite the fuel.

[0028] like Figure 2 As shown, nozzle 1 includes a gaseous fuel supply area, an air supply area, a pulverized coal fuel supply area, and a carbon dioxide regulating area; the gaseous fuel supply area and the air supply area are arranged at the nozzle inlet, the air supply area is arranged above the gaseous fuel supply area, the pulverized coal fuel supply area is arranged on the upper side of the nozzle and close to the nozzle constriction throat nozzle, and the carbon dioxide regulating area is arranged at the nozzle constriction throat nozzle.

[0029] The hydrogen fuel supply area of ​​nozzle 1 includes a carbon dioxide passage 3, an acceleration device 4, a hydrogen passage 5, a gas-gas mixing pipe 6, a pressurizing structure 7, a coal-powder side mixed gas nozzle 8, and an air-side mixed gas nozzle 9. The carbon dioxide passage 3 is connected to the acceleration device 4, which adopts a converging nozzle design. The hydrogen passage 5 is located in a converging section after the outlet of the acceleration device 4 and before the gas-gas mixing pipe 6. After the gas-gas mixing pipe 6 is a expanding section, and after the expanding section is the pressurizing structure 7. The pressurizing structure 7 is a converging and then expanding area formed by the inner and outer pipe walls. The pressurizing structure 7 is divided into upper and lower parts, which are respectively connected to the coal-powder side mixed gas nozzle 8 and the air-side mixed gas nozzle 9. The gas fuel supply area has a shaft inside the nozzle cavity that connects to the left and right sides of the nozzle cavity, dividing the cavity into upper and lower areas. The hydrogen passage 5 drives the ejector of low-pressure, low-speed hydrogen into the gas-gas mixing pipe 6, so that carbon dioxide and hydrogen are fully mixed to achieve the ejection of hydrogen and carbon dioxide.

[0030] The air supply area of ​​the nozzle 1 includes an air passage 10, an air diversion and pressurization area 11, an air inlet grid 12, an air outlet grid 13, and a make-up air passage 14. The air diversion and pressurization area 11 is located near the outlet of the air passage 10 and includes a concave surface extending inward from the inner wall of the nozzle near the outlet of the air passage 10, and a straight surface connecting the concave surface and the inner wall of the nozzle away from the outlet of the air passage 10. One end of the air inlet grid 12 is connected at the junction of the concave surface and the straight surface of the air diversion and pressurization area 11, and the other end is connected at the beginning of the gradually expanding section after the gas-gas mixing pipe 6. The air outlet grid 13 is located after the air diversion and pressurization area 11 and the air inlet grid 12. The area below the gas fuel supply area is the make-up air area 14.

[0031] The pulverized coal fuel supply area of ​​the nozzle 1 includes an ejector air passage 15, a pulverized coal passage 16, an airlock 17, and a gas-solid mixing pipe 18. The air in the ejector air passage 15 passes through a converging region and its outlet is connected to the converging section before the gas-solid mixing pipe 18. The pulverized coal passage 16 is connected to the airlock 17 and is located on the side wall before the converging section before the gas-solid mixing pipe 18, forming a 90° angle with the ejector air passage 15. After the gas-solid mixing pipe 18, it is a gradually expanding and then converging pipe connected to the nozzle cavity.

[0032] The carbon dioxide regulation zone of nozzle 1 includes a carbon dioxide regulation passage 19, a carbon dioxide angle adjuster 20, a carbon dioxide coating pipe 21, a carbon dioxide nozzle 22, and a fuel nozzle 23. The outlet of the carbon dioxide regulation passage 19 is divided into two paths. One path is connected to the nozzle cavity through the carbon dioxide angle adjuster 20, which adjusts the airflow direction by changing the outlet angle. The other path is connected to the carbon dioxide nozzle 22 through the carbon dioxide coating pipe 21. The carbon dioxide coating pipe 21 is a gradually expanding flow channel, which serves to pressurize the flow. The carbon dioxide coating pipe 21 and the carbon dioxide nozzle 22 cover the outside of the fuel nozzle 23, which helps to keep the throat temperature of nozzle 1 constant. The carbon dioxide nozzle 22 sprays high-pressure carbon dioxide to suppress the impact of the shock wave generated by hydrogen deflagration on the combustion of pulverized coal, thereby preventing backfire and protecting the nozzle nozzle 23.

[0033] like Figure 3 As shown, the ignition device 2 includes a linkage rod 24, a condenser lens 25, a high-energy laser beam 26, and a temperature sensor 27. The linkage rod 24 is connected to the condenser lens 25 and can change the angle of the condenser lens 25. The high-energy laser beam 26 can provide sufficient energy to be focused into the furnace through the condenser lens 25. The temperature sensor 27 detects the furnace temperature and automatically shuts off the high-energy laser beam 26 according to the furnace temperature.

[0034] Example 1: Combustion under normal load:

[0035] (1) As Figure 2 As shown, the mixing of hydrogen and carbon dioxide is as follows: Relatively high-speed carbon dioxide is introduced through carbon dioxide passage 3 at a flow rate of 132 kg / h, entering the acceleration device 4. After passing through the nozzle of the acceleration device, the carbon dioxide is accelerated to three times its initial pressure, reaching 0.38 MPa, to meet the ejection requirements. The angles a and b are 35° and 10° respectively. Relatively low-pressure, low-speed hydrogen is introduced through hydrogen passage 5 at a flow rate of 245 kg / h, entering the gas-gas mixing pipe 6 to ensure thorough mixing of hydrogen and carbon dioxide. After passing through the throat of the gas-gas mixing pipe 6, the mixture enters the pressurization structure 7, where the angles c and e are 45°, d and 130° respectively.

[0036] (2) Figure 2 As shown, the air conditioning process is as follows: Hot air with a flow rate of 15 m / s and a temperature of 60°C is introduced through the hot air passage 10. The hot air is divided into two streams by the concave area of ​​the air splitting and pressurizing zone 11. One stream of hot air enters the air inlet grid 12, and its opening is adjusted to control its flow rate. It then passes through the air splitting and pressurizing zone 11 and exits through the air outlet grid 13. The pressurized hot air undergoes its first mixing with the pulverized coal airflow from the gas-solid mixing pipe 18. The other stream of hot air passes through the outer wall of the gas-gas mixing pipe 6 to maintain a constant temperature in the gas-gas mixing pipe 6, after which the airflow flows into the replenishment passage 14.

[0037] (3) Figure 2 As shown, the air and pulverized coal are mixed by injection: the inlet air flow rate is controlled at 110 kg / h through the injection air passage 15, and simultaneously pressurized to 0.30 MPa through the converging zone to achieve the injection effect, with an angle f of 20°. The pulverized coal airflow passes through the airlock 17 to eliminate interference from impurity gases, achieving more efficient air injection. This brings the pulverized coal flow rate to 235 kg / h, with an angle g of 55° and an angle h of 14°. The air then enters the gas-solid mixing pipe 18 to fully mix with the pulverized coal, and after pressurization, it enters the nozzle cavity.

[0038] (4) Figure 2As shown, the two fuel streams are mixed: hydrogen gas from the carbon dioxide ejector is pressurized by the pressurization structure 7 and divided into two streams through the pulverized coal side mixed gas nozzle 8 and the air side mixed gas nozzle 9, with an angle e of 130°. The mixed gas ejected from the pulverized coal side mixed gas nozzle 8 is mixed a second time with the hot air and pulverized coal gas stream, so that the angle between the pulverized coal gas stream and the hydrogen and carbon dioxide mixed gas stream is 90°, thereby achieving the mixing effect of gaseous fuel and solid fuel and realizing the effect of fuel richness separation. The hot air, which has already been heated, enters the supplementary air passage 14 through the outside of the gas-gas mixing pipe 6 to provide oxygen supplementation for the mixed gas fuel ejected through the air side mixed gas nozzle 9, ensuring that the mixed gas fuel reacts vigorously with sufficient oxygen without competing with the solid fuel for oxygen, so that both gaseous and solid fuels have sufficient oxygen for combustion and complete combustion.

[0039] (5) Figure 2 As shown, the carbon dioxide is regulated as follows: The carbon dioxide flow rate is controlled to 20 m / s via the carbon dioxide regulation channel 19, then split into two streams. The first stream flows into the carbon dioxide angle regulator 20, which adjusts its direction to ensure the mixed airflow can enter the nozzle's converging throat for normal combustion in the furnace. The second stream passes through the carbon dioxide coating pipe 21 and the carbon dioxide nozzle 22. The carbon dioxide coating pipe 21 maintains a constant airflow temperature at the converging throat of nozzle 1 and also provides pressurization through its expanding region. The mixed fuel is injected into the furnace through the carbon dioxide nozzle 22, passing through the nozzle's converging throat and fuel nozzle 23. The high-pressure carbon dioxide injected through the nozzle 22 suppresses the impact of the shock wave generated by hydrogen deflagration on pulverized coal combustion, thus preventing backfire and protecting the fuel nozzle 23.

[0040] (6) Figure 3 As shown, the ignition device is activated by adjusting the linkage rod 24 to focus the focal point of the condenser lens 25 at the center of the hydrogen and pulverized coal gas flow, thereby activating the high-energy laser beam 26 to release 10 7 The high-energy laser with an energy density of J / cm is used for heating and ignition. After the temperature sensor 27 shows that the furnace temperature remains constant, the high-energy laser beam 26 is turned off, and the linkage rod 24 is adjusted to return the condenser lens 25 to its original position, thus ending the ignition process.

[0041] Example 2: Reduced load combustion:

[0042] (1) As Figure 2As shown, the mixing of hydrogen and carbon dioxide is as follows: Relatively high-speed carbon dioxide is introduced through carbon dioxide passage 3, with the flow rate adjusted to 80 kg / h. It then enters the acceleration device 4, where it is accelerated through the nozzle to reach three times its initial pressure, reaching 0.38 MPa, to meet the ejection requirements. The hydrogen passage 5 is then opened to reduce the hydrogen flow rate to 180 kg / h, allowing the hydrogen and carbon dioxide to be fully mixed in the gas-gas mixing pipe 6. The mixture then enters the pressurization structure 7 through the gas-gas mixing pipe 6.

[0043] (2) Figure 2 As shown, the air conditioning process is as follows: Hot air with a flow rate of 10 m / s and a temperature of 60°C is introduced through the hot air passage 10. After passing through the air splitting and pressurization zone, the air is divided into two streams. One stream of hot air enters the air inlet grid 12, its opening is adjusted, and then it passes through the air splitting and pressurization zone 11 and exits through the air outlet grid 13. The pressurized hot air undergoes its first mixing with the pulverized coal airflow from the gas-solid mixing pipe 18. The other stream of hot air can pass through the outer wall of the gas-gas mixing pipe 6 to maintain a constant temperature in the gas-gas mixing pipe 6. Afterward, the airflow flows into the replenishment passage 14.

[0044] (3) Figure 2 As shown, the air and pulverized coal are mixed by injection: the inlet air flow rate is controlled at 80 kg / h through the injection air passage 15, and simultaneously pressurized to 0.30 MPa through the converging zone to achieve the injection effect, where the angle f is 20°. The pulverized coal airflow passes through the airlock 17 to eliminate interference from impurity gases, achieving more efficient air injection. This brings the pulverized coal flow rate to 180 kg / h. The air then enters the gas-solid mixing pipe 18 to fully mix with the pulverized coal, and after pressurization, it enters the nozzle cavity.

[0045] (4) Figure 2 As shown, the two fuel streams are mixed: hydrogen gas from the carbon dioxide ejector is pressurized by the pressurization structure 7 and divided into two streams, passing through the pulverized coal side mixed gas nozzle 8 and the air side mixed gas nozzle 9. The mixed gas ejected from the pulverized coal side mixed gas nozzle 8 is mixed a second time with the hot air and pulverized coal gas stream, so that the angle between the pulverized coal gas stream and the hydrogen and carbon dioxide mixed gas stream is 90°, thereby achieving the mixing effect of gaseous fuel and solid fuel and realizing the effect of fuel richness separation. The hot air, which has already been heated, enters the supplementary air passage 14 through the outer wall of the gas-gas mixing pipe 6, providing oxygen supplementation for the mixed gas fuel ejected through the air side mixed gas nozzle 9. This ensures that the mixed gas fuel reacts vigorously with sufficient oxygen without competing with the solid fuel for oxygen, so that both gaseous and solid fuels have sufficient oxygen for combustion and complete combustion.

[0046] (5) Figure 2As shown, the carbon dioxide is regulated as follows: The carbon dioxide flow rate is controlled to 32 m / s via the carbon dioxide regulation channel 19, then split into two streams. The first stream flows into the carbon dioxide angle regulator 20, which adjusts its direction to ensure the mixed airflow can enter the nozzle's converging throat for normal combustion in the furnace. The second stream passes through the carbon dioxide coating pipe 21 and the carbon dioxide nozzle 22. The carbon dioxide coating pipe 21 maintains a constant airflow temperature at the converging throat of nozzle 1 and also provides pressurization through its expanding region. The mixed fuel is injected into the furnace through the carbon dioxide nozzle 22, passing through the nozzle's converging throat and fuel nozzle 23. The high-pressure carbon dioxide injected through the nozzle 22 suppresses the impact of the shock wave generated by hydrogen deflagration on pulverized coal combustion, thus preventing backfire and protecting the fuel nozzle 23.

Claims

1. A combustor based on gas-solid fuel blending, characterized in that: It includes a nozzle (1) and an ignition device (2). The ignition device (2) is arranged above the nozzle (1). After being started, it can irradiate the center area of ​​the fuel sprayed from the nozzle (1) and ignite the fuel. The nozzle (1) includes a gas fuel supply area, an air supply area, a pulverized coal fuel supply area and a carbon dioxide regulating area; the gas fuel supply area and the air supply area are arranged at the nozzle inlet, the air supply area is arranged above the gas fuel supply area, the pulverized coal fuel supply area is arranged on the upper side of the nozzle and close to the nozzle constriction throat nozzle, and the carbon dioxide regulating area is arranged at the nozzle constriction throat nozzle. The gas fuel supply area includes a carbon dioxide passage (3), an acceleration device (4), a hydrogen passage (5), a gas-gas mixing pipe (6), a pressurization structure (7), a coal-powder side mixed gas nozzle (8), and an air-side mixed gas nozzle (9); the carbon dioxide passage (3) is connected to the acceleration device (4), which adopts a converging nozzle form; the hydrogen passage (5) is arranged in a converging section after the outlet of the acceleration device (4) and before the gas-gas mixing pipe (6); after the gas-gas mixing pipe (6) is a diverging section, and after the diverging section is the pressurization structure. Structure (7); The pressurization structure (7) is a region that gradually narrows and then expands between the inner and outer pipe walls. The pressurization structure (7) is divided into upper and lower parts, which are connected to the coal powder side mixed gas nozzle (8) and the air side mixed gas nozzle (9) respectively; The gas fuel supply area is connected to the left and right sides of the nozzle cavity by the shaft inside the nozzle cavity, dividing the cavity where the shaft is located into upper and lower regions; The hydrogen passage (5) drives the low-pressure, low-speed hydrogen to enter the gas-gas mixing pipe (6), so that carbon dioxide and hydrogen are fully mixed to achieve the injection of hydrogen and carbon dioxide; The air supply area includes a hot air passage (10), an air diversion and pressurization area (11), an air inlet grid (12), an air outlet grid (13), and a make-up air area (14). The air diversion and pressurization area (11) is located near the outlet of the hot air passage (10). The air diversion and pressurization area (11) includes a concave surface extending inward from the inner wall of the nozzle near the outlet of the hot air passage (10), and a straight surface connecting the concave surface and the inner wall of the nozzle away from the outlet of the hot air passage (10). One end of the air inlet grid (12) is connected to the junction of the concave surface and the straight surface of the air diversion and pressurization area (11), and the other end is connected to the beginning of the gradually expanding section after the gas-gas mixing pipe (6). The air outlet grid (13) is located after the air diversion and pressurization area (11) and the air inlet grid (12). The area below the gas fuel supply area is the make-up air area (14).

2. A combustor based on gas-solid fuel blending according to claim 1, characterized in that: The angle between the inner wall of the converging section of the acceleration device (4) and the axis is angle a, which is 30°~40°; the angle between the inner wall of the expanding section and the axis is angle b, which is 5°~15°; the angle between the inlet section of the gas-gas mixing pipe (6) and the axis is angle c, which is 40°~50°; the angle between the outlet section and the axis is angle d, which is 15°~25°; the angle between the two inner wall surfaces of the pressurizing structure (7) is angle e, which is 125°~135°.

3. A combustor based on gas-solid fuel blending according to claim 1, characterized in that: The pulverized coal fuel supply area includes an ejector air passage (15), a pulverized coal passage (16), an airlock (17), and a gas-solid mixing pipe (18). The air in the ejector air passage (15) passes through a converging region and its outlet is connected to the converging section before the gas-solid mixing pipe (18). The pulverized coal passage (16) is connected to the airlock (17) and is arranged at a 90° angle to the ejector air passage (15) on the side wall before the converging section before the gas-solid mixing pipe (18). The gas-solid mixing pipe (18) is connected to the nozzle cavity in the form of a gradually expanding and then converging pipe.

4. A combustor based on gas-solid fuel blending according to claim 3, characterized in that: The angle between the inner wall of the tapering section of the ejector air passage (15) and the axis is angle f, which is 15°~25°; the angle between the inlet section of the gas-solid mixing pipe (18) and the axis is angle g, which is 50°~60°; the angle between the outlet section and the axis is angle h, which is 9°~19°.

5. A combustor based on gas-solid fuel blending according to claim 1, characterized in that: The carbon dioxide regulation zone includes a carbon dioxide regulation passage (19), a carbon dioxide angle regulator (20), a carbon dioxide coated pipeline (21), a carbon dioxide nozzle (22), and a fuel nozzle (23). The outlet of the carbon dioxide regulation passage (19) is divided into two paths. One path is connected to the nozzle cavity through the carbon dioxide angle regulator (20). The carbon dioxide angle regulator (20) adjusts the airflow direction by changing the outlet angle. The other path is connected to the carbon dioxide nozzle (22) through the carbon dioxide coated pipeline (21). The carbon dioxide coated pipeline (21) is a gradually expanding flow channel, which serves to pressurize. The carbon dioxide coated pipeline (21) and the carbon dioxide nozzle (22) are wrapped around the outside of the fuel nozzle (23), which serves to control the constant temperature of the throat of the nozzle (1). The carbon dioxide nozzle (22) sprays high-pressure carbon dioxide to suppress the impact of the shock wave generated by the hydrogen deflagration on the combustion of pulverized coal, and at the same time, to prevent backfire and protect the fuel nozzle (23).

6. A combustor based on gas-solid fuel blending according to claim 1, characterized in that: The ignition device includes a linkage rod (24), a condenser lens (25), a high-energy laser beam (26), and a temperature sensor (27). The linkage rod (24) is connected to the condenser lens (25) and can adjust the focusing position of the condenser lens (25). The high-energy laser beam (26) is focused by the condenser lens (25). After being focused, the high-energy laser beam (26) can provide enough energy to ignite the mixture of hydrogen and light coal powder gas over a long distance. The temperature sensor (27) detects the furnace temperature and automatically shuts off the high-energy laser beam (26) according to the furnace temperature.

7. A method for controlling a combustor based on gas-solid fuel blending as described in any one of claims 1 to 6, characterized in that: Includes the following steps: Step 1, Injection of hydrogen and carbon dioxide: The flow rate of carbon dioxide at the nozzle inlet is controlled through the carbon dioxide passage (3). The carbon dioxide in the carbon dioxide passage (3) is accelerated from subsonic to supersonic through the acceleration device (4) to meet the injection conditions. Low-pressure, low-speed hydrogen from the hydrogen passage (5) is injected into the gas-gas mixing tube (6) in the contraction section before the gas-gas mixing tube (6) so that the carbon dioxide and hydrogen are fully mixed. Step 2, air conditioning: The hot air flow rate at the nozzle inlet is controlled through the hot air passage (10). The hot air at the outlet of the hot air passage (10) is turned by the concave surface of the air splitting and pressurizing area (11) and then split into two paths. One hot air flows through the air inlet grid plate (12) and then through the air splitting and pressurizing area to the air outlet grid plate (13), and then enters the nozzle cavity. The other hot air passes through the outer wall of the air-to-air mixing pipe (6) to maintain a constant temperature, and then the air flow flows into the air replenishment area (14). Step 3, mixing of air and pulverized coal: the airflow is controlled by the air ejection passage (15) to accelerate the air through the converging zone and eject the pulverized coal flow through the pulverized coal passage (16). The pulverized coal flow passes through the airlock (17) to lock the pulverized coal entering the gas-solid mixing pipe (18) to make the pulverized coal purer and remove impurities to achieve a better ejection effect. Under the action of air ejection, the pulverized coal and air enter the gas-solid mixing pipe (18) and mix fully to form a pulverized coal flow. The pulverized coal flow passes through the converging nozzle of the gas-solid mixing pipe and enters the nozzle cavity, where it is mixed once with the hot air flowing out of the air outlet grid plate (13) to form a pulverized coal flow. Step 4, gas-solid two-phase mixing: The mixed gas of hydrogen and carbon dioxide from the gas-gas mixing pipe (6) is pressurized by the pressurizing structure (7), and the pressurized mixed gas ejected from the coal powder side mixed gas nozzle (8) is mixed with the hot air and the coal powder airflow in the coal powder fuel supply area for a second time, so that the angle between the coal powder airflow and the hydrogen and carbon dioxide mixed airflow is 90°, so as to achieve the mixing effect of gaseous fuel and solid fuel and realize the effect of fuel concentration separation; the pressurized mixed gas ejected from the air side mixed gas nozzle (9) is mixed with the hot air in the supplementary air area (14), and the hot air in the supplementary air area (14) provides oxygen supplementation for the mixed gas fuel; ensuring that the mixed gas fuel reacts violently with sufficient oxygen, without competing with solid fuel for oxygen, so that both gaseous and solid fuels have sufficient oxygen to burn completely; Step 5, Carbon dioxide regulation: The carbon dioxide from the outlet of the carbon dioxide regulation passage (19) is divided into two paths. One path of carbon dioxide enters the nozzle cavity through the carbon dioxide angle regulator (20). By adjusting the direction of the carbon dioxide angle regulator (20), the direction of the mixed airflow is controlled so that the fuel can enter the nozzle constriction throat nozzle to enter the furnace for normal combustion. The other path of carbon dioxide passes through the carbon dioxide coating pipe (21) and the carbon dioxide nozzle (22). It is injected into the furnace through the carbon dioxide nozzle (22). The mixed fuel is injected into the furnace through the nozzle constriction throat and the fuel nozzle (23). The carbon dioxide nozzle (22) sprays high-pressure carbon dioxide to suppress the impact of the shock wave generated by the hydrogen deflagration on the combustion of pulverized coal, and at the same time, to prevent backfire and protect the fuel nozzle (23). Step 6, ignition device start-up: By adjusting the linkage rod (24) to change the irradiation angle of the condenser lens (25), the high-energy laser beam (26) releases a high-energy-density laser beam to ignite the hydrogen and light coal powder area to achieve the purpose of long-distance ignition; at the same time, after the temperature sensor (27) detects that the furnace temperature is stable, the high-energy laser beam (26) is automatically turned off, and then the condenser lens (25) is reset by the linkage rod (24).

Images