Pulverized coal burner capable of realizing ammonia-doped combustion
By adopting an ammonia stable combustion device and pure oxygen-assisted combustion technology in coal-fired power plants, the problem of unstable ammonia combustion has been solved, achieving efficient mixing of ammonia and pulverized coal, improving combustion efficiency and stability, and reducing carbon dioxide emissions.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GUIZHOU FURAN ENVIRONMENTAL PROTECTION TECH CO LTD
- Filing Date
- 2025-05-20
- Publication Date
- 2026-05-05
AI Technical Summary
The use of ammonia fuel in existing coal-fired power plants suffers from problems such as unstable combustion, short flame dwell time, and easy flameout, resulting in low blending ratios, insufficient carbon emission reduction rates, and difficulty in achieving large-scale replacement of traditional fossil fuels.
An ammonia stable combustion device is used to generate a high-temperature flame by mixing ignition fuel and oxygen, combined with pure oxygen to ensure stable combustion of ammonia in the high-temperature region. The combustion efficiency and stability are improved by swirl and gas film layer technology, realizing staged combustion of pulverized coal and ammonia.
It solves the problem of unstable ammonia combustion, improves the combustion speed and burnout rate of ammonia, reduces unignited escape, achieves efficient mixing of ammonia and pulverized coal, reduces carbon dioxide emissions, and stabilizes the operation of coal-fired boilers.
Smart Images
Figure CN224201713U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of carbon reduction technology in coal-fired power plants, and in particular to a pulverized coal burner that can achieve ammonia-infused combustion. Background Technology
[0002] Carbon reduction technologies for coal-fired power plants include fuel blending technology, carbon capture, utilization and storage, and combustion process optimization technology. Among these, fuel blending technology includes green ammonia blending and biomass blending.
[0003] Ammonia (NH3) (including green ammonia) has shown significant application potential in the energy transition field in recent years. When this fuel burns in pure oxygen or air, its main products are environmentally friendly nitrogen (N2) and water vapor (H2O), fully meeting the environmental protection requirements of zero carbon emissions. In terms of storage and transportation characteristics, NH3 has significant advantages over hydrogen energy: its boiling point at normal pressure is -33.4℃, and it can maintain a liquid state at 20℃ with only 0.86MPa pressure, which reduces its liquefaction energy consumption by nearly 90% compared to liquid hydrogen, significantly improving the economics of large-scale storage and transportation. In terms of safety performance, the explosive limit concentration range of NH3 (15-28%) is significantly narrower than that of hydrogen (4-75%), and its auto-ignition temperature is as high as 651.1℃, fundamentally reducing the risk of deflagration during fuel storage and use.
[0004] However, the application of NH3 as a fuel still faces key technical bottlenecks: First, its high activation energy leads to deteriorated ignition characteristics, with a minimum ignition temperature of 651.1℃, about 300℃ higher than natural gas, making stable ignition difficult to achieve in conventional burners. Second, the combustion reaction kinetics rate is too low; the measured laminar flame propagation speed is only 1 / 5 that of methane (7 cm / s and 35 cm / s respectively when the equivalence ratio Φ=1), resulting in insufficient flame residence time and a high risk of flameout. These characteristics make it difficult to achieve a blending ratio of NH3 exceeding 20% in existing coal-fired power plant boilers, severely restricting its large-scale replacement of traditional fossil fuels. Under the current blending mode, the carbon emission reduction rate is less than 15%, significantly limiting the overall carbon emission reduction potential. Utility Model Content
[0005] In view of this, the purpose of this utility model is to provide a pulverized coal burner that can achieve ammonia-infused combustion.
[0006] The objective of this utility model is achieved through the following technical solution:
[0007] A pulverized coal burner capable of ammonia-infused combustion includes a shell with openings at both ends. One end of the shell is connected to the interior of a coal-fired boiler, and the other end is connected to a pulverized coal supply system. The pulverized coal supply system is equipped with a pulverized coal supply control system. An ammonia stable combustion device is installed inside the shell. The ammonia stable combustion device includes a flame generator that generates a flame by mixing and burning ignition fuel and oxygen, an ammonia inlet device that adds ammonia to the outside of the flame, and a pure oxygen inlet device that adds pure oxygen to the outside of the ammonia. The ammonia inlet device is equipped with an ammonia inlet control system. The ammonia burns stably in the high-temperature region of the flame under oxygen-rich conditions. The flame generated by the combustion ignites the pulverized coal, enabling the pulverized coal and ammonia to be injected into the coal-fired boiler furnace in an ignited combustion state.
[0008] Furthermore, the flame generator includes an ignition fuel delivery pipe and an oxygen delivery pipe. The discharge ends of the ignition fuel delivery pipe and the oxygen delivery pipe are provided with nozzles. The nozzles are provided with ignition devices. The ammonia gas addition device is an ammonia gas delivery pipe sleeved outside the ignition fuel delivery pipe and the oxygen delivery pipe. The ammonia gas delivery pipe has discharge holes distributed at one end of the nozzle. The pure oxygen addition device is a pure oxygen delivery pipe coaxially sleeved outside the ammonia gas delivery pipe. The pure oxygen delivery pipe has several first gas holes distributed on one end face of the nozzle. The feed ends of the ignition fuel delivery pipe, the oxygen delivery pipe, the ammonia gas delivery pipe, and the pure oxygen delivery pipe are located outside the shell, and the nozzle ends are located inside the shell.
[0009] Furthermore, the oxygen delivery pipe is coaxially sleeved outside the ignition fuel delivery pipe.
[0010] Furthermore, the nozzle has multiple nozzle holes corresponding to the oxygen delivery pipe. These multiple nozzle holes are evenly spaced along the circumference of the oxygen delivery pipe and are simultaneously inclined in a clockwise or counterclockwise direction.
[0011] Furthermore, the pure oxygen delivery pipe has a number of second air holes distributed circumferentially on one end sidewall of the nozzle. When the pure oxygen delivery pipe is at one end of the nozzle as a reference, the second air holes are inclined and arranged in multiple spiral rows along the circumference of the pure oxygen delivery pipe.
[0012] Furthermore, the housing includes a straight pipe section and a bent pipe section connected to each other. The bent pipe section is connected to the pulverized coal supply system. The pure oxygen delivery pipe of the ammonia stable combustion device is coaxially located in the straight pipe section, with its inlet end passing through the bent pipe section and its outlet end located inside the straight pipe section.
[0013] Furthermore, an annular baffle is provided on the inner wall of the end of the shell facing the pulverized coal supply system to guide the pulverized coal to the middle of the shell. A cylindrical primary combustion chamber is sleeved on the outer side of the nozzle end of the ammonia stable combustion device. A conical secondary combustion chamber is coaxially provided on the end of the primary combustion chamber away from the ammonia stable combustion device. The small end of the secondary combustion chamber faces the primary combustion chamber and the inner diameter of the small end of the secondary combustion chamber is larger than the outer diameter of the primary combustion chamber. There is a gap between the secondary combustion chamber and the primary combustion chamber to facilitate the entry of some pulverized coal in the shell into the secondary combustion chamber. The primary combustion chamber and the secondary combustion chamber are connected to the inner wall of the shell by a connecting rod or a connecting plate. An external flow channel for pulverized coal is provided between the large end of the secondary combustion chamber and the inner wall of the shell.
[0014] The beneficial effects of this utility model are:
[0015] The pulverized coal burner proposed in this invention, capable of ammonia-blended combustion, utilizes an ammonia stable combustion device. It employs a mixture of ignition fuel and oxygen to generate a flame, with the high-temperature zone reaching 2000℃, far exceeding the ignition point of ammonia, thus heating and igniting the ammonia. Using pure oxygen as the combustion-supporting gas for ammonia ensures rapid combustion, guarantees a high burnout rate, and avoids corrosion of the casing and environmental toxicity. This burner solves the initial ignition problem of ammonia, improves the combustion speed, and minimizes the escape of unignited ammonia.
[0016] This burner ignites the pulverized coal supplied to the coal-fired boiler by the pulverized coal supply system, enabling the pulverized coal and ammonia to be injected into the boiler in a combustion state. This avoids the endothermic ignition process and delayed heat release caused by the pulverized coal directly entering the boiler furnace, and prevents fluctuations in the thermal stability of the furnace under low-load conditions. It achieves stable combustion in ultra-low-load operation of the coal-fired boiler, reducing the use of diesel and natural gas. Because ammonia can burn stably, this burner can significantly increase the mixing ratio of ammonia and pulverized coal, thereby reducing carbon dioxide emissions without reducing the efficiency of the coal-fired boiler.
[0017] Pure oxygen ejected from several first vents on the end face of the pure oxygen delivery pipe is heated and ignited with ammonia in a high-temperature zone. Pure oxygen ejected from several second vents on the side wall of the pure oxygen delivery pipe forms a gas film layer. The gas film layer has the following beneficial effects: 1. The gas film layer can prevent the high temperature generated by combustion from corroding the shell; 2. The gas film layer can intercept and deflect pulverized coal, reducing the amount of pulverized coal directly acting on the flame, thus reducing the risk of flame extinguishing; 3. In the flame and a small area around it, the gas film can slow down the velocity of the pulverized coal, preventing it from directly impacting the flame at a high velocity, thus reducing the risk of flame extinguishing; 4. Because the high-temperature zone of the ammonia stable combustion device is high, when pulverized coal particles enter this zone, they will remain there for a longer time due to the deceleration of the gas film. The temperature difference and longer residence time in this zone make the pulverized coal particles more prone to bursting, further reducing the particle size, which is conducive to the ignition and combustion of pulverized coal and further reduces the risk of flame extinguishing.
[0018] Multiple nozzles corresponding to the oxygen delivery pipe are simultaneously tilted clockwise or counterclockwise, causing the ejected oxygen to swirl, creating a swirling flame. This swirling flame entrains ammonia and pure oxygen, ensuring thorough mixing between the high-temperature flame and ammonia. Several second gas holes are arranged in multiple spiral rows along the circumference of the pure oxygen delivery pipe, also creating a swirling pure oxygen flow. This swirling pure oxygen entrains pulverized coal, ensuring thorough mixing between the pulverized coal and the outer layer of pure oxygen, and allowing the coal to be fully heated and ignited by the heat released from the combustion of ammonia.
[0019] The pulverized coal supplied by the pulverized coal supply system enters the primary combustion chamber under the guidance of the annular baffle. In the primary combustion chamber, the pulverized coal is heated and ignited by the heat released from the combustion of ammonia. The secondary combustion chamber receives the flame from the primary combustion chamber. Some of the pulverized coal in the shell enters the secondary combustion chamber through the gap between the primary and secondary combustion chambers and is heated and ignited by the heat released from the flame. The flame generated by the combustion in the secondary combustion chamber enters the shell and releases heat to heat and ignite the pulverized coal in the shell. This achieves the injection of pulverized coal and ammonia into the coal-fired boiler in a state of combustion, realizing the staged combustion of ammonia and pulverized coal. This solves the problem of the different combustion speeds of ammonia and pulverized coal during the combustion process, the slow combustion of ammonia and its easy escape, which affects the carbon reduction effect and causes environmental pollution.
[0020] Other advantages, objectives, and features of this invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination and study, or may be learned from practice of this invention. The objectives and other advantages of this invention can be realized and obtained through the following description. Attached Figure Description
[0021] To make the objectives, technical solutions, and advantages of this utility model clearer, the following will describe this utility model in further detail with reference to the accompanying drawings, wherein:
[0022] Figure 1 This is a front sectional view of Embodiment 1 of the present utility model.
[0023] Figure 2 for Figure 1 A sectional view of the front section of the ammonia gas stabilization combustion device.
[0024] Figure 3 for Figure 1 A bottom view of the ammonia gas stable combustion device.
[0025] Figure 4 for Figure 2 Enlarged schematic diagram of part A in the middle.
[0026] Figure 5 for Figure 2 Enlarged schematic diagram of section B in the middle.
[0027] Figure 6 This is a front view of the usage status of Embodiment 2 of this utility model on a W-type flame-fired boiler.
[0028] Figure 7 This is a front view of the usage status of Embodiment 2 of this utility model on a counter-firing boiler.
[0029] Figure 8 This is a top view of the usage state of the tangential combustion boiler according to Embodiment 2 of this utility model.
[0030] In the diagram: 1. Ignition fuel delivery pipe; 2. Oxygen delivery pipe; 3. Nozzle; 4. Ammonia delivery pipe; 5. Discharge hole; 6. Pure oxygen delivery pipe; 7. First vent; 8. Second vent; 9. Shell; 10. Ammonia stable combustion device; 11. Burner; 12. Coal-fired boiler; 13. Annular baffle; 14. Primary combustion chamber; 15. Secondary combustion chamber; 16. Pulverized coal supply system. Detailed Implementation
[0031] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be understood that the preferred embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.
[0032] Example 1
[0033] like Figure 1The pulverized coal burner shown is capable of ammonia-infused combustion. It includes a shell 9, which comprises a straight pipe section and a bent pipe section connected to each other. The shell 9 is integrally formed from a high-temperature resistant material. The free end opening of the straight pipe section is connected to the interior of the coal-fired boiler, and the free end opening of the bent pipe section is connected to the pulverized coal supply system. The pulverized coal supply system 16 is equipped with a pulverized coal supply quantity control system. The coal-fired boiler, the pulverized coal supply system, and the pulverized coal supply quantity control system are existing supporting technologies. Inside the shell 9, there is an ammonia stable combustion device 10 whose flame direction is consistent with the direction of pulverized coal supplied by the pulverized coal supply system. The ammonia stable combustion device 10 includes a flame generator that uses a mixture of ignition fuel and oxygen to generate a flame, an ammonia adding device that adds ammonia to the outside of the flame, and a pure oxygen adding device that adds pure oxygen to the outside of the ammonia. The ammonia burns stably in the high-temperature region of the flame under oxygen-rich conditions. The flame generated by the combustion ignites the pulverized coal, realizing the injection of pulverized coal and ammonia into the coal-fired boiler in an ignition and combustion state.
[0034] like Figure 2-5 As shown, the ammonia stable combustion device 10 includes an ignition fuel delivery pipe 1 and an oxygen delivery pipe 2. The oxygen delivery pipe 2 is coaxially sleeved outside the ignition fuel delivery pipe 1. Both the ignition fuel delivery pipe 1 and the oxygen delivery pipe 2 have nozzles 3 at their outlet ends. Each nozzle 3 has multiple nozzle holes corresponding to the oxygen delivery pipe 2. These nozzle holes are evenly spaced along the circumference of the oxygen delivery pipe 2 and are all inclined clockwise. Each nozzle 3 is equipped with an ignition device. The ammonia gas addition device is an ammonia delivery pipe 4 coaxially sleeved outside the oxygen delivery pipe 2. The ammonia delivery pipe 4 has outlet holes 5 distributed at one end of the nozzle 3. The pure oxygen addition device is a pure oxygen delivery pipe 6 coaxially sleeved outside the ammonia delivery pipe 4. The pure oxygen delivery pipe 6 has outlet holes 5 at one end of the nozzle 3. A number of first air holes 7 are distributed on one end face. A number of second air holes 8 are distributed circumferentially on one end side wall of the pure oxygen conveying pipe 6. When the pure oxygen conveying pipe 6 is at one end of the nozzle 3 as a reference, the second air holes 8 are inclined. The number of second air holes 8 are arranged in multiple spirals along the circumference of the pure oxygen conveying pipe 6, with the spiral direction to the left. The pure oxygen conveying pipe 6 of the ammonia stable combustion device 10 is coaxially located in the straight pipe section. The feed ends of the ignition fuel conveying pipe 1, oxygen conveying pipe 2, ammonia conveying pipe 4 and pure oxygen conveying pipe 6 pass through the bend section and are located outside the bend section. The discharge ends are located inside the shell 9. The ignition fuel conveying pipe 1, oxygen conveying pipe 2, ammonia conveying pipe 4 and pure oxygen conveying pipe 6 are high temperature resistant pipes. In this embodiment, the ignition fuel delivery pipe 1 delivers hydrogen, natural gas, or diesel; the oxygen delivery pipe 2 delivers oxygen; the ammonia delivery pipe 4 delivers ammonia (green ammonia); the pure oxygen delivery pipe 6 delivers high-purity oxygen; and the pulverized coal supply system supplies a primary pulverized coal gas flow with a certain velocity to the shell 9.
[0035] like Figure 1As shown, an annular baffle 13 is provided on the inner wall of the straight section of the shell 9 near the bend section to guide the pulverized coal to the middle of the shell 9. The inner hole of the annular baffle 13 is hourglass-shaped. A cylindrical primary combustion chamber 14 is coaxially sleeved on the outer side of the nozzle 3 end of the ammonia stable combustion device 10. A conical secondary combustion chamber 15 is coaxially provided on the end of the primary combustion chamber 14 away from the ammonia stable combustion device 10. The small end of the secondary combustion chamber 15 faces the primary combustion chamber 14 and the inner diameter of the small end of the secondary combustion chamber 15 is larger than the outer diameter of the primary combustion chamber 14. There is a gap between the secondary combustion chamber 15 and the primary combustion chamber 14 to facilitate the entry of some pulverized coal in the shell 9 into the secondary combustion chamber 15. The primary combustion chamber 14 and the secondary combustion chamber 15 are connected to the inner wall of the shell 9 by a connecting rod or a connecting plate. An external flow channel for pulverized coal is provided between the large end of the secondary combustion chamber 15 and the inner wall of the shell 9. The primary combustion chamber 14 and the secondary combustion chamber 15 are made of high-temperature resistant steel and ceramic.
[0036] The pulverized coal burner proposed in this invention, capable of ammonia-infused combustion, utilizes an ammonia stable combustion device. It employs a mixture of ignition fuel and oxygen to generate a flame, with the high-temperature zone reaching 2000℃, far exceeding the ignition point of ammonia, thus heating and igniting the ammonia. Using pure oxygen as the combustion-supporting gas for ammonia ensures rapid combustion, guarantees a high burnout rate, and avoids corrosion of the casing and environmental toxicity. This burner solves the initial ignition problem of ammonia, improves the combustion speed, and minimizes the escape of unignited ammonia.
[0037] This burner ignites the pulverized coal supplied to the coal-fired boiler by the pulverized coal supply system, enabling the pulverized coal and ammonia to be injected into the boiler in an ignition and combustion state. This avoids the endothermic ignition process and delayed heat release of the pulverized coal entering the boiler furnace, and prevents fluctuations in the thermal stability of the furnace under low-load conditions. It achieves stable combustion in ultra-low-load operation of the coal-fired boiler, reducing the use of diesel and natural gas. Because ammonia can burn stably, this burner can significantly increase the mixing ratio of ammonia and pulverized coal, thereby reducing carbon dioxide emissions without reducing the efficiency of the coal-fired boiler.
[0038] Pure oxygen ejected from several first vents on the end face of the pure oxygen delivery pipe is heated and ignited with ammonia in a high-temperature zone. Pure oxygen ejected from several second vents on the side wall of the pure oxygen delivery pipe forms a gas film layer. The gas film layer has the following beneficial effects: 1. The gas film layer can prevent the high temperature generated by combustion from corroding the shell; 2. The gas film layer can intercept and deflect pulverized coal, reducing the amount of pulverized coal directly acting on the flame, thus reducing the risk of flame extinguishing; 3. In the flame and a small area around it, the gas film can slow down the velocity of the pulverized coal, preventing it from directly impacting the flame at a high velocity, thus reducing the risk of flame extinguishing; 4. Because the high-temperature zone of the ammonia stable combustion device is high, when pulverized coal particles enter this zone, they will remain there for a longer time due to the deceleration of the gas film. The temperature difference and longer residence time in this zone make the pulverized coal particles more prone to bursting, further reducing the particle size, which is conducive to the ignition and combustion of pulverized coal and further reduces the risk of flame extinguishing.
[0039] Multiple nozzles corresponding to the oxygen delivery pipe are simultaneously tilted clockwise, causing the ejected oxygen to swirl, creating a swirling flame. This swirling flame entrains ammonia and pure oxygen, achieving a thorough mixing of the high-temperature flame, pure oxygen, and ammonia. Several second gas holes are arranged in multiple spiral rows along the circumference of the pure oxygen delivery pipe, also creating a swirling pure oxygen flow. This swirling pure oxygen entrains pulverized coal, ensuring thorough mixing of the pulverized coal with the outer layer of pure oxygen, which is then fully heated and ignited by the heat released from the combustion of ammonia.
[0040] The pulverized coal supplied by the pulverized coal supply system enters the primary combustion chamber under the guidance of the annular baffle. In the primary combustion chamber, the pulverized coal is heated and ignited by the heat released from the combustion of ammonia. The secondary combustion chamber receives the flame from the primary combustion chamber. Some of the pulverized coal in the shell enters the secondary combustion chamber through the gap between the primary and secondary combustion chambers and is heated and ignited by the heat released from the flame. The flame generated by the combustion in the secondary combustion chamber enters the shell and releases heat to heat and ignite the pulverized coal in the shell. This achieves the injection of pulverized coal and ammonia into the coal-fired boiler in a state of combustion, realizing the staged combustion of ammonia and pulverized coal. This solves the problem of the different combustion speeds of ammonia and pulverized coal during the combustion process, the slow combustion of ammonia and its easy escape, which affects the carbon reduction effect and causes environmental pollution.
[0041] Example 2
[0042] like Figure 6-8 The application of the pulverized coal burner capable of ammonia-infused combustion shown is illustrated in Example 1, which is applied to a coal-fired boiler 11. The coal-fired boiler includes a furnace body 12, on which pulverized coal burners 11 capable of ammonia-infused combustion are distributed. The coal-fired boiler 11 is a tangential combustion boiler, a counter-firing combustion boiler, or a W-type flame combustion boiler.
[0043] The application of pulverized coal burners that enable ammonia-blended combustion utilizes an ammonia-stabilized combustion device. This device uses a mixture of ignition fuel and oxygen to generate a flame. The high-temperature zone of the flame reaches 2000℃, far exceeding the ignition point of ammonia, thus heating and igniting the ammonia. Pure oxygen is used as the combustion-supporting gas for ammonia, resulting in rapid combustion and ensuring a high burnout rate. This avoids corrosion of the casing and environmental toxicity caused by ammonia.
[0044] The application of pulverized coal burners capable of ammonia-blended combustion solves the initial ignition problem of ammonia, increases the combustion speed of ammonia, and minimizes the escape of unignited ammonia. Because this coal-fired boiler utilizes pure oxygen as a combustion aid, it achieves stable ammonia combustion, thus significantly increasing the ammonia-to-pulverized coal blending ratio and reducing coal consumption. This coal-fired boiler achieves carbon reduction with ammonia and enables large-scale consumption of green ammonia (ammonia gas), a new energy source, while simultaneously replacing fossil fuels. The injection of fuel into the coal-fired boiler avoids the endothermic ignition process and delayed heat release of pulverized coal entering the boiler, preventing fluctuations in the furnace's thermal stability under low-load conditions. This achieves stable combustion during ultra-low-load operation of the coal-fired boiler, further reducing the use of diesel and natural gas.
[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of this technical solution, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.
Claims
1. A pulverized coal burner capable of ammonia-infused combustion, characterized in that: It includes a shell (9) with openings at both ends. One end of the shell (9) is connected to the interior of the furnace body (12) of the coal-fired boiler, and the other end is connected to the pulverized coal supply system (16). The pulverized coal supply system (16) is equipped with a pulverized coal supply control system. An ammonia stable combustion device (10) is provided inside the shell (9). The ammonia stable combustion device (10) includes a flame generator that generates a flame by mixing and burning ignition fuel and oxygen, an ammonia adding device that adds ammonia to the outside of the flame, and a pure oxygen adding device that adds pure oxygen to the outside of the ammonia. The ammonia adding device is equipped with an ammonia adding control system. The ammonia burns stably in the high-temperature area of the flame under oxygen-rich conditions. The flame generated by the combustion ignites the pulverized coal, so that the pulverized coal and ammonia are injected into the furnace body of the coal-fired boiler in an ignition and combustion state.
2. The pulverized coal burner capable of ammonia-blended combustion according to claim 1, characterized in that: The flame generator includes an ignition fuel delivery pipe (1) and an oxygen delivery pipe (2). The outlet ends of the ignition fuel delivery pipe (1) and the oxygen delivery pipe (2) are provided with nozzles (3). The nozzles (3) are provided with ignition devices. The ammonia gas addition device is an ammonia gas delivery pipe (4) sleeved outside the ignition fuel delivery pipe (1) and the oxygen delivery pipe (2). The ammonia gas delivery pipe (4) has outlet holes (5) distributed at one end of the nozzle (3). The pure oxygen addition device is a pure oxygen delivery pipe (6) coaxially sleeved outside the ammonia gas delivery pipe (4). The pure oxygen delivery pipe (6) has several first air holes (7) distributed on one end face of the nozzle (3). The inlet ends of the ignition fuel delivery pipe (1), the oxygen delivery pipe (2), the ammonia gas delivery pipe (4) and the pure oxygen delivery pipe (6) are located outside the shell (9), and the nozzle (3) end is located inside the shell (9).
3. The pulverized coal burner capable of ammonia-blended combustion according to claim 2, characterized in that: The oxygen delivery pipe (2) is coaxially sleeved outside the ignition fuel delivery pipe (1).
4. The pulverized coal burner capable of ammonia-blended combustion according to claim 2, characterized in that: The nozzle (3) has multiple nozzles corresponding to the oxygen delivery pipe (2). The multiple nozzles are evenly spaced along the circumference of the oxygen delivery pipe (2) and are simultaneously inclined in a clockwise or counterclockwise direction.
5. The pulverized coal burner capable of ammonia-blended combustion according to claim 2, characterized in that: The pure oxygen delivery pipe (6) has a number of second air holes (8) distributed circumferentially on one end side wall of the nozzle (3). When the pure oxygen delivery pipe (6) is at one end of the nozzle (3) as a reference, the second air holes (8) are inclined. The number of second air holes (8) are arranged in multiple spirals along the circumference of the pure oxygen delivery pipe (6).
6. The pulverized coal burner capable of ammonia-blended combustion according to claim 1, characterized in that: The housing (9) includes a straight pipe section and a bend pipe section connected to each other. The bend pipe section is connected to the pulverized coal supply system. The pure oxygen delivery pipe (6) of the ammonia stable combustion device (10) is coaxially located in the straight pipe section, and its feed end passes through the bend pipe section, while its discharge end is located in the straight pipe section.
7. The pulverized coal burner capable of ammonia-blended combustion according to any one of claims 1-6, characterized in that: An annular baffle (13) is provided on the inner wall of the end of the shell (9) facing the pulverized coal supply system to guide the pulverized coal to the middle of the shell (9). A cylindrical primary combustion chamber (14) is sleeved on the outer side of the nozzle (3) of the ammonia stable combustion device (10). A conical secondary combustion chamber (15) is coaxially provided on the end of the primary combustion chamber (14) away from the ammonia stable combustion device (10). The small end of the secondary combustion chamber (15) faces the primary combustion chamber (14) and the inner diameter of the small end of the secondary combustion chamber (15) is larger than the outer diameter of the primary combustion chamber (14). There is a gap between the secondary combustion chamber (15) and the primary combustion chamber (14) to facilitate the entry of some pulverized coal in the shell (9) into the secondary combustion chamber (15). The primary combustion chamber (14) and the secondary combustion chamber (15) are connected to the inner wall of the shell (9) by a connecting rod or a connecting plate. An external flow channel for pulverized coal is provided between the large end of the secondary combustion chamber (15) and the inner wall of the shell (9).