A pulverized coal burner and a boiler based on hydrogen-based decomposition ammonia re-combustion

Abstract

The present application relates to the technical field of combustor, a pulverized coal combustor based on hydrogen-based decomposition ammonia afterburning, comprising: ammonia gas activation equipment for activating ammonia gas by brown gas combustion and forming mixed gas; the first end of mixed gas delivery pipe is connected to ammonia gas activation equipment, and the second end is a mixed gas output end; a combustion pipe is sleeved outside the mixed gas delivery pipe, the second end of the mixed gas delivery pipe is arranged inside the combustion pipe, and an oxygen input pipe is connected to the side wall of the combustion pipe and communicates with the inside of the combustion pipe; a plurality of coal powder input pipes are connected to the side wall of the combustion pipe in annular array, the coal powder input pipes are adjacent to the second end of the mixed gas delivery pipe and are located below the second end of the mixed gas delivery pipe. The pulverized coal combustor can combine ammonia gas activation preheating with coal powder participation, can significantly adjust the position of the combustion zone, can adjust the combustion position, and can optimize the combustion effect. The present application also proposes a boiler using the pulverized coal combustor based on hydrogen-based decomposition ammonia afterburning.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of burners, in particular to a pulverized coal burner based on hydrogen-based decomposition of ammonia re-combustion and a boiler. BACKGROUND

[0002] In the prior art, a pulverized coal burner is generally used in a boiler to ignite the pulverized coal. With the growing demand for environmental protection and energy transformation worldwide, the potential of hydrogen energy as a clean energy source is increasingly recognized. Hydrogen does not produce carbon dioxide during combustion, which is an important means to achieve a low-carbon economy. However, the storage and transportation of hydrogen remain major obstacles to its widespread application. To address this issue, ammonia (NH3) is widely studied as a carrier of hydrogen. Ammonia has the advantages of high hydrogen content, easy liquefaction, and storage, but challenges still exist in the efficient use of ammonia, particularly in its combustion and decomposition technology.

[0003] Currently, the pre-decomposition combustion technology of ammonia mainly faces several problems: first, the combustion efficiency of ammonia is low and harmful emissions such as nitrogen oxides (NOx) are easily produced; second, the decomposition of ammonia usually requires high temperatures, leading to increased energy consumption and equipment complexity.

[0004] In the prior art, some technologies also add ammonia gas to the pulverized coal burner, for example, Chinese patent: A water-spraying hydrogen-injected ultra-low-nitrogen ammonia-coal mixed-combustion gas-solid two-phase burner (publication number CN115949936B), which has a cylindrical coal powder gas flow channel in the center, and a multi-stage ammonia injection system and a multi-stage atomized water injection system around the coal powder gas flow channel; the multi-stage ammonia injection system includes multiple stages of ammonia injection devices that are not connected to each other, and the multi-stage atomized water injection system includes multiple stages of water injection devices, each stage of ammonia injection device and each stage of water injection device are arranged radially from the inside to the outside around the coal powder gas flow channel; each stage of ammonia injection device is provided with multiple ammonia gas outlets distributed along the circumference of the coal powder gas flow channel, and the ammonia gas outlets are communicated with the ammonia injection pipes; each stage of water injection device is provided with multiple mist water outlets distributed along the circumference of the coal powder gas flow channel, and the mist water outlets are communicated with the water supply pipes. The present application can ensure continuous and stable combustion of ammonia / coal by multi-stage ammonia / coal mixed combustion. At the same time, the multi-stage atomized water injection system provides H and OH free radicals during ammonia / coal mixed combustion, reducing the concentration of nitrogen oxides emissions produced during combustion.

[0005] One of the main structures of this type of burner is to set the coal powder passage at the center of the burner, and to rotate the coal powder by cyclone. However, this type of burner cannot set the coal powder passage at the periphery, for example, by setting a pre-activation device for ammonia gas in a simple structure, the pre-activated ammonia gas cannot be combined with the coal powder input. Changing the position of the combustion zone is beneficial to reducing nitrogen oxides (NOx) emissions, and the existing technology is difficult to adjust the position of the combustion zone in the burner, SUMMARY

[0006] To solve the above problems, the application provides a pulverized coal burner based on hydrogen-based decomposition of ammonia re-combustion, which can combine ammonia gas activation and preheating with pulverized coal participation, and can significantly adjust the position of the combustion zone, adjust the combustion position and optimize the combustion effect.

[0007] To achieve the above object, the application adopts the technical scheme of:

[0008] A pulverized coal burner based on hydrogen-based decomposition of ammonia re-combustion, comprising:

[0009] An ammonia gas activation device for activating ammonia gas by Brown gas combustion and forming a mixed gas;

[0010] A mixed gas delivery pipe, a first end of which is connected to the ammonia gas activation device, and a second end of which is a mixed gas output end;

[0011] A combustion pipe, which is sleeved outside the mixed gas delivery pipe, and the second end of the mixed gas delivery pipe is arranged inside the combustion pipe,

[0012] An oxygen input pipe, which is connected to the side wall of the combustion pipe and communicates with the inside of the combustion pipe, and is used for delivering oxygen to the inside of the combustion pipe;

[0013] A plurality of pulverized coal input pipes, which are connected to the side wall of the combustion pipe in an annular array, are arranged adjacent to and below the second end of the mixed gas delivery pipe.

[0014] Preferably, the extension direction of the end of the pulverized coal input pipe is the tangential direction of the combustion pipe.

[0015] Preferably, a flow guide device for swirling the input oxygen is further arranged between the combustion pipe and the mixed gas delivery pipe, and the flow guide device is arranged at the same height as the pulverized coal input pipe.

[0016] Preferably, the flow guide device comprises a plurality of flow guide vanes, which are arranged in a same-height annular manner around the mixed gas delivery pipe, the inner side end of the flow guide vane is universal-jointed with the outer wall of the mixed gas delivery pipe, and the outer part of the combustion pipe corresponding to the position of the flow guide vane has a synchronous driving device connected to the outer side end of the flow guide vane, which is used for driving the flow guide vane to rotate synchronously at the same angle.

[0017] As preferred, the outer end of the guide vane is connected with a driving shaft, the driving shaft passes through the combustion pipe, a gear is installed on the end of the driving shaft away from the guide vane, the combustion pipe is provided with a plane bearing above and below the gear, the plane bearing is a gear plate on the side towards the gear, and the gear plate is engaged with the gear, the synchronous driving device further comprises a driving device in transmission connection with one of the gear plates to drive the gear plate to rotate.

[0018] As preferred, a plurality of outwardly opening angle-adjustable guide plates are circumferentially distributed on the end of the combustion pipe.

[0019] As preferred, the inner wall of the combustor is provided with an annular protruding structure, the annular protruding structure is located in a reduced diameter section between the end of the combustor and the second end of the mixed gas delivery pipe.

[0020] As preferred, a tertiary gas input system is arranged near the end of the combustion pipe, the tertiary gas input system comprises a main input pipe, a buffer cavity, a high-pressure input pipe and a low-pressure input pipe, the output end of the main input pipe is connected with the buffer cavity, the high-pressure input pipe and the low-pressure input pipe are both in communication with the buffer cavity, the output end of the high-pressure input pipe is connected between the reduced diameter section and the end of the combustion pipe, and the output end of the low-pressure input pipe is connected with the reduced diameter section.

[0021] As preferred, a plurality of shunt pipes are arranged on the annular protruding structure, and the output ends of the shunt pipes are distributed along the axial direction of the combustion pipe.

[0022] In another aspect, the present application provides a boiler using the pulverized coal combustor based on hydrogen-based decomposition ammonia re-combustion.

[0023] The present application has the following advantages:

[0024] The pulverized coal combustor based on hydrogen-based decomposition ammonia re-combustion of the present application inputs ammonia gas after activation into the combustion pipe, synchronously inputs pulverized coal, oxygen and mixed gas containing ammonia gas after activation into the combustion zone through the pulverized coal input pipe arranged at the side wall of the combustion pipe, and can significantly improve the burnout efficiency of the pulverized coal and reduce the amount of ash compared with the general pulverized coal input mode in which the pulverized coal input pipe is arranged at the position of the combustion zone of the combustion pipe.

[0025] The flow guide device arranged at the position of coal powder input has two advantages, one is that the direction of oxygen input can be changed, the axial flow of oxygen is changed into rotational flow, the rotational flow speed of oxygen is changed by adjusting the direction of flow guide blade, the height of combustion zone in the combustion pipe is adjusted, and finally the combustion effect is changed; the other is that the coal powder is introduced into the combustion pipe at the position with the fastest rotational flow speed, and the coal powder, oxygen and mixed gas containing ammonia are premixed. After the experimental data is verified, the coal powder burning effect is significantly improved due to the combustion effect of the coal powder input into the combustion pipe at the position corresponding to the combustion zone.

[0026] The tertiary gas input system inputs one or a combination of reducing gas, protective gas or atomized water at the position between the reduced diameter section and the end of the combustion pipe through Bernoulli effect, can form a gas deficient area at the end position of the combustion pipe, provides a reducing environment, and reduces nitrogen oxide (NOx) emission. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is a schematic diagram of the coal powder burner based on hydrogen-based decomposition of ammonia reburning in the first embodiment of the present application.

[0028] Figure 2 It is Figure 1 It is a schematic diagram of the flow guide device.

[0029] Figure 3 It is a top view schematic diagram of the arrangement angle of the coal powder input pipe.

[0030] Figure 4 It is a schematic diagram of the coal powder burner based on hydrogen-based decomposition of ammonia reburning in the second embodiment of the present application.

[0031] Figure 5 It is a schematic diagram of the coal powder burner based on hydrogen-based decomposition of ammonia reburning in the third embodiment of the present application.

[0032] Figure 6 It is a diagram of the position of the corresponding combustion zone and the flame effect when different amounts of ammonia gas are input.

[0033] The reference signs include:

[0034] 10-heating combustion pipe, 11-Brown gas input pipe, 12-ammonia gas input pipe, 13-first igniter, 14-combustion pipe, 15-mixed gas delivery pipe, 16-oxygen input pipe, 17-second igniter, 18-reduced diameter section, 19-flow guide plate, 110-tertiary gas input system, 1101-main input pipe, 1102-buffer cavity, 1103-high pressure input pipe, 1104-low pressure input pipe, 1105-shunt pipe;

[0035] 21 - drive device, 22 - flow guide device, 221 - lower plain bearing, 222 - lower toothed disc, 223 - external tooth structure, 224 - drive shaft, 225 - upper plain bearing, 226 - upper toothed disc, 227 - gear wheel, 228 - flow guide vane, 23 - pulverized coal input pipe. DETAILED DESCRIPTION

[0036] In order to make the objectives, technical solutions and advantages of the present technical solution clearer, the present technical solution will be further described in detail below with specific embodiments. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present technical solution.

[0037] Embodiment 1

[0038] The present embodiment proposes a pulverized coal burner based on hydrogen-based decomposition of ammonia re-combustion. The present pulverized coal burner is based on hydrogen-based decomposition of ammonia re-combustion to realize ammonia gas activation and then ammonia gas combustion. Specifically, the present pulverized coal burner based on hydrogen-based decomposition of ammonia re-combustion comprises: an ammonia gas activation device for activating ammonia gas by Brown gas combustion and forming a mixed gas; a mixed gas delivery pipe 15 connected at a first end to the ammonia gas activation device and having a second end as a mixed gas output end; a combustion pipe 14 sleeved outside the mixed gas delivery pipe 15, the second end of the mixed gas delivery pipe 15 being arranged inside the combustion pipe 14; an oxygen input pipe 16 connected to a side wall of the combustion pipe 14 and in communication with the inside of the combustion pipe 14 for delivering oxygen to the inside of the combustion pipe 14; and a plurality of pulverized coal input pipes 23 connected in an annular array to the side wall of the combustion pipe 14, the pulverized coal input pipes 23 being adjacent to and below the second end of the mixed gas delivery pipe 15.

[0039] Specifically, the ammonia gas activation device comprises a heat-increasing combustion pipe 10 as a device required for ammonia gas activation, the lower end of the heat-increasing combustion pipe 10 being provided with a Brown gas input pipe 11, the side of the Brown gas input pipe 11 being provided with a first lighter 13 for igniting Brown gas inside the heat-increasing combustion pipe 10, the heat-increasing combustion pipe 10 being provided with an ammonia gas input pipe 12 at a position corresponding to the end of the Brown gas input pipe 11 inside the heat-increasing combustion pipe 10, the ammonia gas input pipe 12 being slightly lower than the end of the Brown gas input pipe 11.

[0040] As in the above structure, the Brown gas can be ignited by the first igniter 13 after being input into the heating combustion tube 10. In order to ensure that the hydrogen-oxygen mixture can be effectively and stably combusted in the combustion heating chamber, the molar ratio of the hydrogen-oxygen mixture made of electrolytic water is H2:O2=2:1, and the flame propagation speed of the hydrogen-oxygen mixture is about 2.0-2.5 m / s. According to the specifications of the burner and the demand for hydrogen from the decomposition of ammonia, the diameter of the output end of the Brown gas tube needs to be optimized and designed according to the outlet flow rate of the hydrogen-oxygen mixture, the ammonia flow rate, and the pressure in the combustion heating chamber. The outlet flow rate of the hydrogen-oxygen mixture should be greater than its flame propagation speed and less than the blowout limit of the hydrogen flame, so as to ensure that the hydrogen-oxygen mixture can be stably combusted. The ammonia flow rate in the combustion heating chamber will affect the pressure in the combustion heating chamber and the disturbance of air flow to the flame combustion stability, and the diameter of the output end of the Brown gas tube needs to be as large as possible while ensuring the stable combustion of the hydrogen-oxygen mixture.

[0041] The hydrogen-based decomposition ammonia re-combustion device described above is used to implement a hydrogen-based decomposition ammonia re-combustion method, which includes introducing Brown gas into a closed space and igniting the Brown gas, introducing ammonia gas during the ignition of the Brown gas, and heating and activating the ammonia gas during the combustion of the Brown gas; the products after the combustion of the Brown gas and the high-temperature ammonia gas are introduced out and additional combustion-supporting gas is added, and the mixed gas is ignited to achieve the effect of ammonia gas combustion.

[0042] The chemical reaction of ammonia and hydrogen combustion is a chain reaction, which goes through chain initiation, propagation, and termination. The chain initiation requires external factors (heat, high-energy molecular collision). Due to its high dissociation energy (N-H bond dissociation energy is about 391 kJ / mol), the combustion process of ammonia often faces the problems of low combustion efficiency and high ignition energy. Hydrogen (H2) is a highly efficient fuel, and during its combustion process, a series of active radicals are generated. These radicals have strong reactivity, and the radicals (H radicals, OH radicals, etc.) generated during the combustion of hydrogen are used as high-energy molecules to effectively participate in the chain reaction of ammonia combustion. Free radicals are atoms or molecules with unpaired electrons, which makes them highly reactive in chemical reactions. The introduction of these chain reaction mechanisms not only reduces the decomposition strength of the N-H bond in the NH3 molecule, thereby reducing the activation energy of ammonia decomposition, but also accelerates the process of converting ammonia into nitrogen and hydrogen.

[0043] The mixed gas formed after the ammonia gas and the Brown gas inside the heating combustion tube 10 are combusted is delivered to the combustion tube 14 through the mixed gas delivery tube 15, and the oxygen input tube 16 is arranged at a position close to the lower end of the tube wall of the combustion tube 14, which enters the space between the mixed gas delivery tube 15 and the combustion tube 14, in the process, the input oxygen is affected by the temperature rise, and then delivered to the end of the mixed gas delivery tube 15. In the process, the pulverized coal input tube 23 delivers the pulverized coal into the mixed gas, which is ignited by the second lighter 17, at this time, the ammonia gas is fully combusted to release heat, and the pulverized coal in the mixed gas is also fully combusted.

[0044] As preferred, as shown in the figure, a guide device 22 for swirling the input oxygen is further arranged between the combustion tube 14 and the mixed gas delivery tube 15, and the guide device 22 is arranged at the same height as the pulverized coal input tube 23. The guide device 22 arranged at the position of the pulverized coal input has two points, one is to change the direction of the input oxygen, from axial flow to swirling flow, and the swirling speed of the oxygen is changed by adjusting the direction of the guide vane 228, and then the height of the combustion zone in the combustion tube 14 is adjusted, and finally the combustion effect is changed; the second is to guide the pulverized coal into the combustion tube 14 at the position with the fastest swirling speed, and the pulverized coal, oxygen and mixed gas containing ammonia are premixed. After verification by experimental data, the combustion effect of the pulverized coal after mixing is significantly improved. Figure 1

[0045] As shown in the figure, in particular, the guide device 22 includes a plurality of guide vanes 228, which are arranged in a ring shape at the same height around the mixed gas delivery tube 15, the inner side end of the guide vane 228 is universal jointed with the outer wall of the mixed gas delivery tube 15, and the outer side end of the guide vane 228 is connected with the synchronous driving device 21 arranged at the position corresponding to the guide vane 228 outside the combustion tube 14, which is used to drive the guide vane 228 to rotate synchronously and at the same angle. The outer side end of the guide vane 228 is connected with the driving shaft 224, the driving shaft 224 penetrates through the combustion tube 14, and the gear 227 is arranged at the end of the driving shaft 224 away from the guide vane, and the combustion tube 14 is provided with the upper plane bearing 225 and the lower plane bearing 221 above and below the gear 227, respectively, and the plane bearing is provided with a toothed disc on the side facing the gear 227, and the toothed disc is engaged with the gear 227, and the synchronous driving device 21 further includes the driving device 21 connected with one of the toothed discs to drive the toothed disc to rotate. The upper toothed disc 226 and the lower toothed disc 222 rotate synchronously with the gear 227. Figure 2

[0046] ​​In this embodiment, the driving device 21 drives the tooth structure through the output shaft, drives the lower tooth disc 222 through the outer tooth structure 223 in the lower plane bearing 221, and drives all the gear wheels 227 synchronously due to the meshing of the lower tooth disc 222 and the gear wheel 227. In this embodiment, 12 guide vanes 228 are arranged in the flow guide device 22, and the flow guide device 22 can drive the 12 guide vanes 228 to deflect synchronously and at the same angle through the above structure. Since the oxygen input by the oxygen input pipe 16 is guided through the internal space of the combustion pipe 14 and moves axially upward, it is deflected to the cyclone after being guided by the flow guide device 22.

[0047] In combination Figure 3 As shown in the figure, the extension direction of the end of the pulverized coal input pipe 23 is the tangent direction of the combustion pipe 14. Specifically, the tangent direction of the pulverized coal input by the pulverized coal input pipe 23 is the same as the cyclone direction of the oxygen. When the oxygen passes through the flow guide device 22 to form a significant cyclone effect, the input of the pulverized coal can also form a rapid and large-angle cyclone effect.

[0048] A second igniter 17 is arranged at the end of the mixed gas delivery pipe 15, which is used to ignite the activated ammonia gas. Since the pulverized coal is in a rapid and large-angle cyclone state when it passes through the burning ammonia gas, that is, the pulverized coal is fully burned after entering the combustion zone.

[0049] As shown in the figure, the extension direction of the end of the pulverized coal input pipe 23 is the tangent direction of the combustion pipe 14. Specifically, the tangent direction of the pulverized coal input by the pulverized coal input pipe 23 is the same as the cyclone direction of the oxygen. When the oxygen passes through the flow guide device 22 to form a significant cyclone effect, the input of the pulverized coal can also form a rapid and large-angle cyclone effect. Figure 6

[0050] The pulverized coal burner based on hydrogen-based decomposition and ammonia reburning provided by the present application inputs the activated ammonia gas into the combustion pipe 14, synchronously inputs the pulverized coal, oxygen and mixed gas containing activated ammonia gas into the combustion zone through the pulverized coal input pipe 23 arranged at the position of the side wall of the combustion pipe 14, and compared with the general pulverized coal input mode in which the pulverized coal input pipe 23 is arranged at the position of the combustion zone of the combustion pipe 14, the pulverized coal burner can significantly improve the burning efficiency of the pulverized coal and reduce the amount of ash.

[0051] The main effect of the pulverized coal burner in this embodiment is to arrange the pulverized coal passage at the positions around, for example, to arrange the pre-activation device of ammonia gas through a simple structure, which cannot be combined with the input of the pulverized coal after pre-activating the ammonia gas. At the same time, changing the position of the combustion zone is beneficial to reducing the emission of nitrogen oxides (NOx).

[0052] Embodiment 2

[0053] As​Figure 4 As shown, the pulverized coal burner based on hydrogen-based decomposition of ammonia reburning in this embodiment has the same basic structure as the pulverized coal burner based on hydrogen-based decomposition of ammonia reburning in Example 1, with the difference being the provision of a guide plate 19 at the end of the combustion tube 14. The guide plate 19 is used to radially guide the airflow inward, forming a reduced diameter section 18 around the combustion zone, creating an exhaust gas region, thereby enhancing pulverized coal combustion and reducing NOx generation.

[0054] Example 3

[0055] like Figure 5 As shown, the pulverized coal burner based on hydrogen-based decomposition of ammonia reburning in this embodiment has the same basic structure as the pulverized coal burner based on hydrogen-based decomposition of ammonia reburning in Example 1, the difference being that a reduced diameter section 18 and a tertiary gas input system 110 are provided.

[0056] like Figure 5 As shown, an annular protrusion structure is provided on the inner wall of the burner. The section where the annular protrusion structure is located is a diameter-reducing section 18 , which is located between the end of the burner and the second end of the mixed gas delivery pipe 15 .

[0057] Specifically, a tertiary gas input system 110 is disposed near the end of the combustion tube 14. This system comprises a main input tube 1101, a buffer chamber 1102, a high-pressure input tube 1103, and a low-pressure input tube 1104. The output end of the main input tube 1101 is connected to the buffer chamber 1102, while both the high-pressure input tube 1103 and the low-pressure input tube 1104 are in communication with the buffer chamber 1102. The output end of the high-pressure input tube 1103 is connected between the reduced diameter section 18 and the end of the combustion tube 14, while the output end of the low-pressure input tube 1104 is connected to the reduced diameter section 18. Multiple diverter tubes 1105 are disposed on the annular protrusion, with their output ends distributed along the axial direction of the combustion tube 14.

[0058] The tertiary gas input system 110 inputs reducing gas or atomized water, or a combination of the two, into the position between the reduced diameter section 18 and the end of the combustion tube 14 through the Bernoulli effect, thereby forming a depleted gas area at the end of the combustion tube 14, providing a reducing environment, and reducing nitrogen oxide (NOx) emissions.

[0059] In the first scheme of the embodiment, the pressurized nitrogen gas is input through the main input pipe 1101, and after the nitrogen gas is released in the buffer cavity 1102, the pressurized nitrogen gas is synchronously input to the high-pressure input pipe 1103 and the low-pressure input pipe 1104. Because of the pressure of the gas inside the combustion pipe 14 on the inner wall of the combustion pipe 14, the pressure at the reduced diameter section 18 is less than the pressure of the combustion pipe 14 above the reduced diameter section 18, so most of the gas is discharged through the shunt pipe 1105 at the reduced diameter section 18, and a small amount of gas is discharged from the low-pressure input pipe 1104, so that a gas depletion zone is generated around and above the burner. The nitrogen oxides (NOx) formed by the combustion of ammonia and oxygen are reduced by the residual coal powder, so as to reduce the generation of nitrogen oxides (NOx).

[0060] In the second scheme of the embodiment, after the mixed fluid of nitrogen and water is input through the main input pipe 1101, the water and the ammonia gas are synchronously input to the buffer cavity 1102, and the water is atomized and discharged through the shunt pipe 1105. At this time, the distal end of the shunt pipe 1105 is provided with an atomizing nozzle. The nitrogen gas is discharged through the low-pressure input pipe 1104, and the atomized water is separated to form H radicals and OH radicals after passing through the combustion zone. At the same time, due to the action of the nitrogen gas, a gas depletion zone is generated above the combustion zone, and the H radicals reduce the nitrogen oxides (NOx) in the high-temperature environment.

[0061] In the embodiment, because the positions of the high-pressure input pipe 1103 and the low-pressure input pipe 1104 are different, the three-time gas input system 110 generates a pressure difference between the reduced diameter section 18 and the flared section through the Bernoulli effect. The fluid output by the three-time gas input system 110 can automatically adjust the proportion of the fluid input by the high-pressure input pipe 1103 and the low-pressure input pipe 1104 according to the different flow rates of the fluid in the combustion pipe 14, so as to widely adjust the combustion effect in the combustion zone.

[0062] The application also provides a boiler using the pulverized coal burner based on the hydrogen radical decomposition ammonia re-combustion.

[0063] The above is only a preferred embodiment of the application, and those skilled in the art can make many changes in the specific implementation and application range according to the technical content of the application, as long as the changes do not deviate from the concept of the application, and all belong to the protection scope of the patent.

Claims

1. A pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion, characterized by: include: Ammonia activation equipment, which is used to activate ammonia and form a mixed gas by Brown's gas combustion; A mixed gas delivery pipe, the first end of which is connected to the ammonia activation device and the second end of which is a mixed gas output end; The combustion tube is sleeved on the outside of the mixed gas delivery tube, and the second end of the mixed gas delivery tube is arranged inside the combustion tube. an oxygen input pipe connected to the side wall of the combustion tube and communicating with the interior of the combustion tube for supplying oxygen to the interior of the combustion tube; Pulverized coal inlet pipes, which are connected to the side wall of the combustion tube in a circular array, and the pulverized coal inlet pipes are adjacent to the second end of the mixed gas delivery pipe and are located below the second end of the mixed gas delivery pipe; The inner wall of the burner is provided with an annular protrusion structure, and the section where the annular protrusion structure is located is a reduced diameter section, and the reduced diameter section is located between the end of the burner and the second end of the mixed gas delivery pipe; A tertiary gas input system is provided on the outside of the combustion tube near the end thereof, the tertiary gas input system comprising a main input tube, a buffer chamber, a high-pressure input tube, and a low-pressure input tube. The output end of the main input tube is connected to the buffer chamber, the high-pressure input tube and the low-pressure input tube are both in communication with the buffer chamber, the output end of the high-pressure input tube is connected between the reduced diameter section and the end of the combustion tube, and the output end of the low-pressure input tube is connected to the reduced diameter section. A plurality of diverter tubes are provided on the annular protrusion, and the output ends of the plurality of diverter tubes are distributed along the axial direction of the combustion tube.

2. The pulverized coal burner based on hydrogen-based decomposition of ammonia and reburning according to claim 1 is characterized in that: The extending direction of the end of the pulverized coal input pipe is the tangential direction of the combustion pipe.

3. The pulverized coal burner based on hydrogen-based decomposition of ammonia and reburning according to claim 1 is characterized in that: A flow guide device for swirling the input oxygen is further provided between the combustion tube and the mixed gas delivery tube, and the flow guide device is provided at a position equal to the coal powder input tube.

4. The pulverized coal burner based on hydrogen-based decomposition of ammonia and reburning according to claim 3 is characterized in that: The guide device includes a plurality of guide vanes, which are arranged in a ring shape with equal height around the mixed gas delivery pipe. The inner ends of the guide vanes are universally hinged to the outer wall of the mixed gas delivery pipe. The position of the guide vanes on the outside of the combustion tube is provided with a synchronous drive device, which is connected to the outer ends of the guide vanes and is used to drive the guide vanes to rotate synchronously at the same angle.

5. The pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion according to claim 4 is characterized in that: The outer end of the guide vane is connected to a drive shaft, which passes through the combustion tube. A gear is installed at the end of the drive shaft away from the backflow vane. Plane bearings are provided above and below the corresponding gears of the combustion tube. The plane bearing is a geared disc facing the gear, and the geared disc is engaged with the gear. The synchronous drive device also includes a drive device, which is transmission-connected to one of the geared discs to drive the geared disc to rotate.

6. The pulverized coal burner based on hydrogen-based decomposition of ammonia and reburning according to claim 1 is characterized in that: The end of the combustion tube is evenly distributed along the circumference with a plurality of guide plates with adjustable outward opening angles.

7. A boiler using a pulverized coal burner, characterized in that: The pulverized coal burner is a pulverized coal burner based on hydrogen-based decomposition of ammonia and reburning as described in any one of claims 1 to 6.

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