CN116734255A - An ammonia burner that can form a pre-combustion cage flame inside - Google Patents

Abstract

The invention discloses an ammonia burner capable of forming precombustion cage flames inside, wherein a combustion gas flow pipeline is arranged in a burner shell, and an air inlet for injecting air into the burner shell is arranged on the burner shell; the gas flow pipeline comprises an ammonia pipeline with a gas inlet positioned outside the burner shell, a gas outlet positioned inside the front end of the burner shell, and a gas pipeline with a gas inlet positioned outside the burner shell, a gas outlet positioned inside the front end of the burner shell and positioned behind the gas outlet of the ammonia pipeline; the guide vane is arranged in the burner shell and used for providing air for the gas at the gas outlet of the ammonia pipeline and the gas at the gas outlet of the gas pipeline and wrapping the gas at the gas outlet of the ammonia pipeline and the gas at the gas outlet of the gas pipeline to move towards the outside of the front end of the burner shell. The invention provides a high-temperature anoxic atmosphere for ammonia gas, so that the ammonia gas is decomposed into hydrogen and nitrogen as much as possible, and combustion heat supply and self-heating decomposition of the ammonia gas are realized.

Description

An ammonia burner that can form a pre-combustion cage flame inside

Technical field

The present invention relates to the technical field of burners, and specifically refers to an ammonia burner that can form a pre-combustion envelope flame inside.

Background technique

Currently, countries around the world are actively seeking effective ways to reduce carbon dioxide emissions. my country has put forward the strategic goal of "strive to peak carbon dioxide emissions before 2030 and strive to achieve carbon neutrality before 2060." Faced with the urgent need for carbon emission reduction, ammonia fuel has received unprecedented attention in recent years because of its "zero carbon and rich hydrogen". Ammonia fuel can be produced carbon-free through renewable electricity and transported safely and efficiently in the form of liquid ammonia. At the same time, ammonia fuel has a high hydrogen density and can be directly burned and utilized in energy power devices such as gas turbines, electric thermal boilers, and internal combustion engines without the need for dehydrogenation. . However, compared with traditional fossil fuels such as oil and natural gas, ammonia fuel has unique properties such as difficulty in ignition, slow flame propagation, difficulty in flame stabilization, and potential for high nitrogen oxide emissions. This is a key issue that must be considered when burning ammonia. In order to achieve efficient, stable, safe and clean combustion of ammonia fuel, burner design is crucial. Therefore, it is very necessary to design a burner suitable for burning ammonia fuel (including pure ammonia or ammonia-mixed fuel), in order to obtain better ignition, stable combustion, burnout and Emission characteristics.

Chinese patent document (CN115264496A) discloses an ammonia burner and a control method of an ammonia burner, which can realize pure ammonia combustion and carbon-based fuel mixed with ammonia combustion. However, in this patent document, pure ammonia combustion requires a certain amount of ammonia to pass through. An additional external ammonia decomposer decomposes it into hydrogen and nitrogen. Among them, the hydrogen formed by decomposition has the function of supporting combustion, and the nitrogen oxides generated after the nitrogen in ammonia is decomposed and converted into nitrogen will be reduced. However, due to the existence of an additional ammonia decomposer, the burner has a complex structure, high processing difficulty, large installation and use space, and limited application range.

Chinese patent document (CN217763418U) discloses a catalytic graded ammonia burner, which proposes that a catalyst can be used to decompose ammonia fuel into hydrogen for combustion as much as possible and reduce the generation of nitrogen oxides, which has similar effects to the above-mentioned patent document (CN115264496A). However, the pure ammonia combustion in this patent document is to catalytically convert ammonia into hydrogen combustion as much as possible. The cost of the catalyst is high, the cost of regular replacement and maintenance is high, the catalytic structure is relatively complex, and it is difficult to process and use, and the catalytic conversion of ammonia and low nitrogen oxidation The combustion effect of the material needs to be considered.

Chinese patent document (CN113294801A) discloses a combustion device and its control method that can achieve efficient and clean combustion of pure ammonia. It can achieve efficient and stable combustion of pure ammonia without mixing other combustible gases, and at the same time in a single combustion chamber Low-level emissions of nitrogen oxides in combustion exhaust gas can be achieved. However, in this patent document, the ammonia gas needs to be passed through an additional ammonia pyrolysis electric heater to pyrolyze part of the ammonia gas into hydrogen and nitrogen. At the same time, an ammonia pyrolysis catalyst is used inside the heater, which has a high cost and structure. complex.

Chinese patent document (CN112648113A) discloses a green and efficient ammonia fuel combustion system and method. By appropriately adjusting the fuel supply, pollutant emissions are controlled at a low level. It also solves the problem of poor ignitability of ammonia as a fuel. The problem. However, in the patent document, the green and efficient combustion of ammonia requires the use of additional methane cracking devices and ammonia decomposition devices to partially convert methane and ammonia into hydrogen for combustion. The structure is complex and maintenance is difficult.

Chinese patent document (CN112902163A) discloses a hydrogen-doped low-nitrogen combustion system and method based on ammonia decomposition. Ammonia is decomposed into hydrogen as the combustion gas and air is used as the oxygen supplier. The low-nitrogen combustion system solves the problem of hydrogen transportation. problem, increasing the combustion heat release rate and reducing nitrogen oxide emissions. However, in this patent document, an additional ammonia decomposition device and nitrogen removal device need to be installed, which results in high processing costs and complex structure.

Chinese patent document (CN216244251U) discloses a rapid pyrolysis ammonia and combustion device, which can quickly decompose ammonia into hydrogen and realize the combustion of hydrogen, thereby reducing the large amount of carbon dioxide emissions caused by conventional coal combustion and avoiding environmental pollution. However, in this patent document, a catalytic barrel needs to be installed inside the ammonia gun, and a high-cost catalyst needs to be used. The catalytic structure is complex and the cost of regular replacement and maintenance is high.

Through the above analysis, it can be found that cracking ammonia through high-temperature pyrolysis and catalytic conversion before burning it is an effective method to reduce the formation of nitrogen oxides and promote fuel ignition and combustion. However, problems and defects in the existing technology are: the design of ammonia burners requires the use of external or built-in catalytic and cracking components to decompose ammonia into hydrogen for post-combustion or combustion support. The structure of such a burner is relatively complex and the cost is high. High, maintenance is difficult, and the catalytic conversion effect needs to be considered.

Contents of the invention

The purpose of the present invention is to solve the above-mentioned deficiencies in the background technology and provide an ammonia burner that achieves efficient and stable combustion by forming a pre-combustion cage flame inside.

In order to achieve this goal, the ammonia burner designed in the present invention can form a pre-combustion cage flame inside, including a burner housing, a gas circulation pipe is provided in the burner housing, and a useful gas flow pipe is provided on the burner housing. An air inlet for injecting air into the interior; the gas circulation pipe includes an air inlet located outside the burner housing, an air outlet located inside the front end of the burner housing, an ammonia gas pipeline and an air inlet located inside The outside of the burner housing and the gas outlet are located inside the front end of the burner housing and a gas pipeline located behind the gas outlet of the ammonia gas pipeline; the burner housing is provided with a gas pipe for supplying the ammonia gas The gas at the gas outlet of the pipeline and the gas at the gas outlet of the gas pipeline provide air and wrap the gas at the gas outlet of the ammonia pipeline and the gas at the gas outlet of the gas pipeline to the burner shell. The guide vanes move externally at the front end of the body.

Further, the gas circulation pipeline has a sleeve-type structure, and the gas pipeline is coaxially and fixedly connected to the ammonia gas pipeline.

Furthermore, the front end of the ammonia gas pipeline has a closed structure, and a plurality of ammonia gas outlets are provided at intervals along the circumferential direction of the ammonia gas pipeline.

Further, the inner surface of the front end of the gas pipeline is coaxially fixedly connected to the circumferential outer surface of the ammonia gas pipeline, and the front end of the gas pipeline is provided with a plurality of gas outlets spaced apart along its circumferential direction. The gas outlet is located behind the ammonia outlet.

Further, the front end of the ammonia gas pipeline and the front end of the gas pipeline are both frustum-shaped closed structures with a small front end and a large rear end.

Further, both the ammonia gas outlet hole and the gas gas outlet hole are beveled holes inclined toward the front end of the burner housing.

Further, the guide vane is an annular structure, the middle part of which is coaxially fixed on the gas pipe, and the outer surface of the guide vane is fixed on the inner surface of the burner housing. The blade is located behind the gas outlet of the gas pipe.

Further, a plurality of direct-flow air for providing air to the gas at the gas outlet of the gas pipeline and the gas at the gas outlet of the ammonia gas pipe are spaced on the inner side of the guide vane along its circumferential direction. hole.

Further, a plurality of air outlets extending from the outer surface of the guide vane to the inside of the guide vane and used to wrap the gas pipe are spaced on the outer side of the guide vane along its circumferential direction. The gas at the outlet of the ammonia gas pipe and the gas at the outlet of the ammonia gas pipe move toward the outside of the front end of the burner housing through the swirling air slot.

Furthermore, the ratio of the ventilation area of the direct flow air hole to the ventilation area of the swirling air slot is 1:5 to 1:6.

The beneficial effects of the present invention are: through the sleeve-type gas circulation pipeline structure, the present invention provides a high-temperature and oxygen-deficient atmosphere for ammonia in the form of a pre-combustion cage flame, so that ammonia can be decomposed into hydrogen and nitrogen as much as possible , realizes the combustion heat supply and autothermal decomposition of ammonia, making ammonia easier to ignite and stabilize combustion, and also achieves the generation and emission of low nitrogen oxides, while avoiding the use of complex and costly ammonia catalytic conversion devices . The ammonia burner designed by the invention has a simple structure, low maintenance cost and avoids complex pipeline design. The guide blades are equipped with inner and outer layers of air outlets. The inner air outlet provides direct air to prevent gas backflow and cools the pipe wall. The outer air outlet provides swirling air to wrap the ammonia airflow forward and provide ammonia combustion. Most of the air is needed to promote ammonia combustion and stable combustion, achieving controllable fuel-air zones. In the present invention, the outlet of the ammonia pipeline and the outlet of the gas pipeline are small holes with a certain bevel angle. Such a structure makes the gas and air of the pre-combustion cage flame more evenly mixed, and at the same time, the ammonia gas is more concentrated and More evenly distributed in the high temperature and oxygen-deficient atmosphere provided by the pre-combustion cage flame. The outlet end of the ammonia gas pipeline has a certain chamfer to avoid the occurrence of a local high temperature area in front of the outlet end of the ammonia gas pipeline, which may cause damage to the burner and the generation of high nitrogen oxides. The technology of the present invention innovatively proposes the ammonia combustion idea of creating a high-temperature oxygen-deficient atmosphere in the form of a pre-combustion cage flame, converting ammonia into hydrogen as much as possible, and realizing self-thermal decomposition of combustion heat. The invention does not rely on catalytic conversion or decomposition components, has a simple structure, strong reliability, and low processing, manufacturing, operation and maintenance costs. It also solves the problems of difficulty in igniting ammonia fuel, slow flame propagation, difficulty in flame stabilization, and high nitrogen oxide emissions. , the ammonia burner designed by the application of the present invention can extend the service life of the boiler and generator set of the current power station, and solve the problem of the generator set being forced to retire early due to carbon dioxide emission restrictions. The ammonia burner designed by the present invention can be used for the ammonia-incorporated combustion transformation of coal-fired, oil-fired, and gas-fired boilers, and can also be used in other combustion thermal devices such as gas turbines, glass kilns, cement kilns, and steel blast furnaces, reducing carbon dioxide from the source. emissions without requiring excessive modifications to the original combustion device.

Description of drawings

Figure 1 is a perspective view of an ammonia burner that can form a pre-combustion cage flame inside in Embodiment 1 of the present invention;

Figure 2 is a perspective view of the internal structure of an ammonia burner that can form a pre-combustion cage flame in Embodiment 1 of the present invention;

Figure 3 is a structural perspective view of the gas circulation pipeline in Embodiment 1 of the present invention;

Figure 4 is a perspective view of the guide vane in Embodiment 1 of the present invention;

Figure 5 is a front view of the guide vane in Embodiment 1 of the present invention;

Figure 6 is an axial cross-sectional view of an ammonia burner that can form a pre-combustion cage flame inside in Embodiment 1 of the present invention;

Figure 7 is a schematic diagram of the combustion state of an ammonia burner that can form a pre-combustion cage flame inside in Embodiment 1 of the present invention;

Figure 8 is a perspective view of an ammonia burner that can form a pre-combustion cage flame inside in Embodiment 2 of the present invention;

Figure 9 is a perspective view of the internal structure of an ammonia burner that can form a pre-combustion cage flame in Embodiment 2 of the present invention;

Figure 10 is a perspective view of the guide vane in Embodiment 2 of the present invention;

Figure 11 is a front view of the guide vane in Embodiment 2 of the present invention;

Figure 12 is an axial cross-sectional view of an ammonia burner that can form a pre-combustion cage flame inside in Embodiment 2 of the present invention;

Figure 13 is a schematic diagram of the combustion state of an ammonia burner that can form a pre-combustion cage flame inside in Embodiment 2 of the present invention;

Among them, 1—burner shell, 2—air inlet, 3—ammonia pipeline, 4—gas pipeline, 5—guide vanes, 6—ammonia gas outlet, 7—gas gas outlet, 8—DC air hole, 9 - swirling air tank, 10 - pre-combustion cage flame zone, 11 - ammonia flame zone, 12 - ammonia decomposition zone, 13 - ammonia combustion zone, 14 - ammonia burnout zone, 15 - gas inlet.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

The first embodiment of an ammonia burner designed by the present invention that can form a pre-combustion cage flame inside, as shown in Figures 1-6, includes a burner shell 1, and the burner shell 1 is provided with a device for injecting gas into the interior. The air inlet 2 of the air is provided with a gas circulation pipeline in the burner housing 1; the gas circulation pipeline includes an ammonia gas pipeline 3 with an air inlet located outside the burner housing 1 and an air outlet located inside the front end of the burner housing 1 The gas pipeline 4 has an air inlet located outside the burner housing 1 and a gas outlet located inside the front end of the burner housing 1 and behind the gas outlet of the ammonia gas pipeline 3; the burner housing 1 is provided with a gas pipe 4 for supplying ammonia The gas at the gas outlet of the gas pipeline 3 and the gas at the gas outlet of the gas pipeline 4 provide air and wrap the gas at the gas outlet of the ammonia gas pipeline 3 and the gas at the gas outlet of the gas pipeline 4 to the burner housing 1 Guide vanes 5 that move externally at the front end.

As shown in Figures 2-3 and 6, the gas circulation pipeline has a sleeve-type structure, and the front and rear ends of the gas pipeline 4 are coaxially and fixedly connected to the ammonia gas pipeline 3. The front end of the ammonia gas pipeline 3 has a closed structure and a chamfered structure. The front end of the ammonia gas pipeline 3 has a plurality of ammonia gas outlet holes 6 spaced apart along its circumferential direction. The front end of the gas pipeline 4 is provided with a plurality of gas outlet holes 7 at intervals along its circumferential direction. The gas outlet holes 7 are located behind the ammonia gas outlet hole 6 . The front end of the gas pipe 4 is also provided with a chamfer structure. The ammonia gas outlet hole 6 and the gas outlet hole 7 are both beveled holes inclined toward the front end of the burner housing 1, and the bevel angle is 45°.

As shown in Figures 2 and 4-6, the guide vane 5 is an annular structure, the middle part of which is coaxially fixed on the gas pipe 4, and the outer surface of the guide vane 5 is fixed on the inner surface of the burner housing 1. The guide vane 5 is located behind the gas outlet of the gas pipe 4 . A plurality of direct-flow air holes 8 for providing air to the gas at the gas outlet of the gas pipeline 4 and the gas at the gas outlet of the ammonia gas pipeline 3 are spaced on the inner side of the guide vane 5 along its circumferential direction. The outer side of the guide vane 5 is spaced along its circumferential direction with a plurality of pipes extending from the outer surface of the guide vane 5 to the inner side of the guide vane 5 for wrapping the gas at the outlet of the gas pipeline 4 and the ammonia gas pipeline 3 The gas at the outlet moves toward the outside of the front end of the burner housing 1. The swirl air groove 9 has a groove surface that is a swirl slope of 15° with the horizontal direction. The ratio of the ventilation area of the direct flow air hole 8 to the ventilation area of the swirling air slot 9 is 1:6.

As shown in Figure 7, the method of using the ammonia burner in the first embodiment designed by the present invention is: before injecting ammonia for combustion, first inject natural gas through the gas pipeline 4 for fuel-rich combustion to provide a high-temperature and oxygen-deficient combustion atmosphere. Natural gas concentration is 1.7. After the pre-combustion cage flame gas combustion provides a high-temperature oxygen-deficient atmosphere, ammonia gas is injected from the ammonia gas pipeline 3 and ejected from the ammonia gas outlet hole 6. At this time, the ammonia gas can be converted into as much as possible in the pre-combustion cage flame zone. Hydrogen, nitrogen, and decomposed ammonia are easier to ignite and stabilize combustion, achieving lower generation and emissions of nitrogen oxides, and avoiding the use of complex and costly ammonia catalytic conversion devices.

The second embodiment of an ammonia burner designed by the present invention that can form a pre-combustion cage flame inside is shown in Figures 8-12. It includes a burner housing 1. The front end of the burner housing 1 has a chamfered structure. The burner housing 1 is provided with an air inlet 2 for injecting air into the interior. The burner housing 1 is provided with a gas circulation pipe; the gas circulation pipe includes an air inlet located outside the burner housing 1 and an air outlet located at the combustion chamber. The ammonia gas pipeline 3 and the air inlet inside the front end of the burner housing 1 are located outside the burner housing 1. The gas outlet is located inside the front end of the burner housing 1 and the gas pipeline 4 located behind the outlet of the ammonia gas pipeline 3. ; The burner housing 1 is provided with a device for providing air to the gas at the outlet of the ammonia pipeline 3 and the gas at the gas outlet of the gas pipeline 4 and wrapping the gas at the outlet of the ammonia pipeline 3 and the gas pipeline 4 The guide vanes 5 move the gas at the outlet toward the outside of the front end of the burner housing 1 .

As shown in Figures 9 and 12, the gas circulation pipeline has a sleeve-type structure, and the front and rear ends of the gas pipeline 4 are coaxially and fixedly connected to the ammonia gas pipeline 3. The front end of the ammonia gas pipeline 3 has a closed structure and a chamfered structure. The front end of the ammonia gas pipeline 3 has a plurality of ammonia gas outlet holes 6 spaced apart along its circumferential direction. The front end of the gas pipeline 4 is provided with a plurality of gas outlet holes 7 at intervals along its circumferential direction. The gas outlet holes 7 are located behind the ammonia gas outlet hole 6 . The front end of the gas pipe 4 is also provided with a chamfer structure. The ammonia gas outlet hole 6 and the gas outlet hole 7 are both beveled holes inclined toward the front end of the burner housing 1, and the bevel angle is 45°.

As shown in Figures 9-12, the guide vane 5 is an annular structure, the middle part of which is coaxially fixed on the gas pipe 4, and the outer surface of the guide vane 5 is fixed on the inner surface of the burner housing 1. 5 is located behind the gas outlet of the gas pipeline 4. There are two circles of DC air holes 8 spaced along the radial direction of the guide vane 5 . Each circle of DC air holes 8 includes DC air holes 8 spaced apart along the circumferential direction of the guide vane 5 . The DC air holes 8 It is used to provide air to the gas at the gas outlet of the gas pipeline 4 and the gas at the gas outlet of the ammonia gas pipeline 3. The outer side of the guide vane 5 is spaced along its circumferential direction with a plurality of pipes extending from the outer surface of the guide vane 5 to the inner side of the guide vane 5 for wrapping the gas at the outlet of the gas pipeline 4 and the ammonia gas pipeline 3 The gas at the outlet moves toward the outside of the front end of the burner housing 1. The swirl air groove 9 has a groove surface that is a swirl slope of 15° with the horizontal direction. The ratio of the ventilation area of the direct flow air hole 8 to the ventilation area of the swirling air slot 9 is 1:6.

As shown in Figure 13, the method of using the ammonia burner in the second embodiment designed by the present invention is: before injecting ammonia for combustion, first inject natural gas through the gas pipeline 4 for fuel-rich combustion to provide a high-temperature and oxygen-deficient combustion atmosphere. Natural gas concentration is 1.7. After the pre-combustion cage flame gas combustion provides a high-temperature oxygen-deficient atmosphere, ammonia gas is injected from the ammonia gas pipeline 3 and ejected from the ammonia gas outlet hole 6. At this time, the ammonia gas can be converted into as much as possible in the pre-combustion cage flame zone. Hydrogen, nitrogen, and decomposed ammonia are easier to ignite and stabilize combustion, achieving lower generation and emissions of nitrogen oxides, and avoiding the use of complex and costly ammonia catalytic conversion devices. Compared with the first embodiment, the second embodiment is that the front end structure of the burner housing 1 is optimized into a chamfered structure and the number of DC air holes 8 is increased, which further prevents the high-temperature flame from burning at the front end of the ammonia burner and damaging the ammonia. At the same time, more direct-flow air holes 8 further meet the requirements for burning out ammonia and stabilizing combustion.

To sum up, the present invention provides a high-temperature and oxygen-deficient atmosphere for ammonia in the form of a pre-combustion cage flame through a sleeve-type gas circulation pipeline structure, so that ammonia can be decomposed into hydrogen and nitrogen as much as possible, achieving It eliminates the combustion heat supply and autothermal decomposition of ammonia, making ammonia easier to ignite and stabilize combustion. It also achieves the generation and emission of low nitrogen oxides, while avoiding the use of complex and costly ammonia catalytic conversion devices. The ammonia burner designed by the invention has a simple structure, low maintenance cost and avoids complex pipeline design. The guide blade 5 is provided with inner and outer layers of air outlets. The inner air outlet provides direct air to prevent gas backflow and cools the pipe wall. The outer air outlet provides swirling air to wrap the ammonia airflow forward and provide ammonia combustion. Most of the air required promotes ammonia combustion and stable combustion, achieving controllable fuel-air zones. In the present invention, the outlet of the ammonia pipeline 3 and the outlet of the gas pipeline 4 are small holes with a certain bevel angle. This structure makes the gas and air of the pre-combustion package flame more evenly mixed, and at the same time, the ammonia gas is more evenly mixed. Concentrated and more evenly distributed in the high temperature and oxygen-deficient atmosphere provided by the pre-combustion cage flame. The outlet end of the ammonia gas pipeline 4 has a certain chamfer to avoid the occurrence of a local high temperature area in front of the outlet end of the ammonia gas pipeline, which may cause damage to the burner and the generation of high nitrogen oxides. The technology of the present invention innovatively proposes the ammonia combustion idea of creating a high-temperature oxygen-deficient atmosphere in the form of a pre-combustion cage flame, converting ammonia into hydrogen as much as possible, and realizing self-thermal decomposition of combustion heat. The invention does not rely on catalytic conversion or decomposition components, has a simple structure, strong reliability, and low processing, manufacturing, operation and maintenance costs. It also solves the problems of difficulty in igniting ammonia fuel, slow flame propagation, difficulty in flame stabilization, and high nitrogen oxide emissions. , the ammonia burner designed by the application of the present invention can extend the service life of the boiler and generator set of the current power station, and solve the problem of the generator set being forced to retire early due to carbon dioxide emission restrictions. The ammonia burner designed by the present invention can be used for the ammonia-incorporated combustion transformation of coal-fired, oil-fired, and gas-fired boilers, and can also be used in other combustion thermal devices such as gas turbines, glass kilns, cement kilns, and steel blast furnaces, reducing carbon dioxide from the source. emissions without requiring excessive modifications to the original combustion device.

The above descriptions are only preferred embodiments of the present invention and do not impose any formal restrictions on the structure of the present invention. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims (10)

1. An ammonia burner that can form a pre-combustion cage flame inside, including a burner housing (1), characterized in that: a gas circulation pipe is provided in the burner housing (1), and the burner The housing (1) is provided with an air inlet (2) for injecting air into the interior; The gas circulation pipeline includes an air inlet located outside the burner housing (1), an ammonia gas pipeline (3) with an air outlet located inside the front end of the burner housing (1), and an air inlet located at the front end of the burner housing (1). The outside of the burner housing (1) and the gas outlet are located inside the front end of the burner housing (1) and in the gas pipeline (4) behind the gas outlet of the ammonia gas pipeline (3); The burner housing (1) is provided with a device for providing air to the gas at the gas outlet of the ammonia gas pipe (3) and the gas at the gas outlet of the gas pipe (4) and wrapping the ammonia gas. The guide vanes (5) move the gas at the gas outlet of the pipe (3) and the gas at the gas outlet of the gas pipe (4) toward the outside of the front end of the burner housing (1). 2. The ammonia burner according to claim 1, which can form a pre-combustion cage flame inside, is characterized in that: the gas circulation pipe is a sleeve-type structure, and the gas pipe (4) is coaxially fixedly connected to the On the ammonia gas pipeline (3). 3. The ammonia burner according to claim 2, which can form a pre-combustion cage flame inside, is characterized in that: the front end of the ammonia gas pipeline (3) is a closed structure, and the front end of the ammonia gas pipeline (3) is a closed structure. A plurality of ammonia gas outlet holes (6) are spaced along its circumferential direction. 4. The ammonia burner capable of forming a pre-combustion cage flame inside as claimed in claim 3, characterized in that: the inner surface of the front end of the gas pipeline (4) is coaxially fixedly connected to the ammonia gas pipeline (3) On the circumferential outer surface of the gas pipeline (4), a plurality of gas outlet holes (7) are provided at intervals along the circumferential direction of the gas pipe (4). The gas outlet holes (7) are located in the ammonia gas outlet hole (6). ) of the rear. 5. The ammonia burner according to claim 4, which can form a pre-combustion cage flame inside, is characterized in that: the front end of the ammonia gas pipeline (3) and the front end of the gas pipeline (4) are both front-end small. Large frustum-shaped closed structure at the rear end. 6. The ammonia burner capable of forming a pre-combustion cage flame inside as claimed in claim 4 or 5, characterized in that: the ammonia gas outlet hole (6) and the gas outlet hole (7) are both oriented toward the The front end of the burner housing (1) is inclined with a chamfered hole. 7. The ammonia burner capable of forming a pre-combustion cage flame inside as claimed in claim 1, 2 or 4, characterized in that: the guide vane (5) is an annular structure, the middle part of which is coaxially fixed to the On the gas pipeline (4), the outer surface of the guide vane (5) is fixed on the inner surface of the burner housing (1), and the guide vane (5) is located on the gas pipeline (4). ) behind the air outlet. 8. The ammonia burner according to claim 7, which can form a pre-combustion cage flame inside, characterized in that: the inner side of the guide vane (5) is provided with a plurality of spaced apart along the circumferential direction for providing the direction to the desired direction. The gas at the gas outlet of the gas pipeline (4) and the gas at the gas outlet of the ammonia gas pipeline (3) provide direct-flow air holes (8) for air. 9. The ammonia burner according to claim 8, which can form a pre-combustion cage flame inside, characterized in that: the outer side of the guide vane (5) is provided with a plurality of guide vanes spaced along its circumferential direction. The outer surface of the flow vane (5) extends toward the inner side of the flow guide vane (5) and is used to wrap the gas at the outlet of the gas pipeline (4) and the outlet of the ammonia gas pipeline (3). The swirling air slot (9) moves the gas toward the outside of the front end of the burner housing (1). 10. The ammonia burner capable of forming a pre-combustion cage flame inside as claimed in claim 9, characterized in that: the ventilation area of the DC air hole (8) and the ventilation area of the swirl air groove (9) The ratio is 1:5~1:6.