Pulverized coal burner based on hydrogen-based ammonia decomposition and recombustion and boiler

Abstract

The invention relates to the technical field of combustors, in particular to a pulverized coal combustor based on hydrogen-based ammonia decomposition and recombustion, comprising: an ammonia activation device for activating ammonia through Brown gas combustion and forming a mixed gas; the first end of the mixed gas conveying pipe is connected to the ammonia activation equipment, and the second end is a mixed gas output end; the combustion pipe is sleeved outside the mixed gas conveying pipe, the second end of the mixed gas conveying pipe is arranged inside the combustion pipe, and the oxygen input pipe is connected with the side wall of the combustion pipe and is communicated with the inside of the combustion pipe; the multiple pulverized coal input pipes are connected to the side wall of the combustion pipe in an annular array mode, and the pulverized coal input pipes are close to the second end of the mixed gas conveying pipe and located below the second end of the mixed gas conveying pipe. According to the pulverized coal burner, ammonia activation preheating and pulverized coal mixing can be combined, meanwhile, the position of a combustion area can be remarkably adjusted, the combustion position can be adjusted, and the combustion effect can be optimized. The invention further provides a boiler using the pulverized coal burner based on hydrogen-based ammonia decomposition and recombustion.

Description

Technical Field

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

[0002] In the prior art, boilers generally use pulverized coal burners to pass pulverized coal into the boiler for ignition. As the global demand for environmental protection and energy transformation continues to grow, the potential of hydrogen as a clean energy source is increasingly recognized. Hydrogen does not produce carbon dioxide during combustion and is an important means to achieve a low-carbon economy. However, the storage and transportation of hydrogen remain the main obstacles to its widespread application. In order to solve this problem, ammonia (NH3) has been widely studied as a hydrogen carrier. Ammonia has the advantages of high hydrogen content and easy liquefaction and storage, but there are still challenges in the efficient utilization of ammonia, especially in its combustion and decomposition technology.

[0003] At present, the pre-decomposition combustion technology of ammonia mainly faces several problems: first, the combustion efficiency of ammonia is low and it is easy to produce harmful emissions such as nitrogen oxides (NOx); second, the decomposition of ammonia usually requires higher temperatures, resulting in increased energy consumption and increased equipment complexity.

[0004] In the prior art, some technologies also add ammonia to the pulverized coal burner, such as the Chinese patent: a water-sprayed hydrogenated ultra-low nitrogen ammonia coal mixed combustion gas-solid two-phase burner (publication number CN115949936B), the center of the burner is provided with a cylindrical pulverized coal airflow channel, and a multi-stage ammonia spray system and a multi-stage atomization water spray system are provided around the pulverized coal airflow channel; the multi-stage ammonia spray system includes multiple stages of ammonia spray devices that are not connected to each other, and the multi-stage atomization water spray system includes multiple stages of water spray devices, and each stage of ammonia spray devices and each stage of water spray devices are arranged in sequence from the inside to the outside along the radial direction around the pulverized coal airflow channel; each stage of the ammonia spray device is provided with a plurality of ammonia outlets distributed along the circumference of the pulverized coal airflow channel, and the ammonia outlet is connected to the ammonia injection pipe; each stage of the water spray device is provided with a plurality of mist water outlets distributed along the circumference of the pulverized coal airflow channel, and the mist water outlet is connected to the water supply pipe. The present invention can ensure the continuous and stable combustion of ammonia / coal by multi-stage ammonia / coal blending. At the same time, a multi-stage atomizing water spray system is set up to provide H and OH free radicals during the combustion of ammonia / coal mixture, thereby reducing the emission concentration of nitrogen oxides produced by combustion.

[0005] A major structure of this type of burner is to set the pulverized coal channel at the axial center of the burner, and to circulate the pulverized coal through a cyclone. However, this type of burner cannot set the pulverized coal channel at the surrounding positions. For example, when ammonia pre-activation equipment is set up through a simple structure, the ammonia pre-activation cannot be combined with the pulverized coal input. Changing the position of the combustion zone is conducive to reducing nitrogen oxide (NOx) emissions. This type of burner in the prior art is difficult to adjust the position of the combustion zone in the burner. Summary of the invention

[0006] In order to solve the above problems, the present invention proposes a pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion, which can combine ammonia activation preheating with coal powder participation, and can significantly adjust the position of the combustion zone, adjust the combustion position, and optimize the combustion effect. In addition, the present invention also proposes a boiler using the above pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion.

[0007] To achieve the above object, the technical solution adopted by the present invention is:

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

[0009] Ammonia activation equipment, which is used to activate ammonia and form a mixed gas by Brown's gas combustion;

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

[0011] 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.

[0012] an oxygen input pipe connected to the side wall of the combustion tube and communicating with the interior of the combustion tube, and used for delivering oxygen to the interior of the combustion tube;

[0013] There are several pulverized coal input pipes connected to the side wall of the combustion pipe in an annular array. The pulverized coal 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.

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

[0015] Preferably, a flow guide device for swirling the input oxygen is 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.

[0016] Preferably, the guide device includes a plurality of guide vanes, which are arranged in an isohymetric ring around the mixed gas delivery pipe, and the inner ends of the guide vanes are universally hinged to the outer walls of the mixed gas delivery pipe. The outside of the combustion tube has a synchronous drive device at the position corresponding to the guide vanes, 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.

[0017] Preferably, 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 gear of the combustion tube. The plane bearing is a geared disc facing the gear, and the geared disc is meshed 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.

[0018] Preferably, a plurality of guide plates with adjustable outward opening angles are evenly distributed along the circumferential direction at the end of the combustion tube.

[0019] Preferably, an annular protrusion structure is provided on the inner wall of the burner, 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.

[0020] Preferably, a tertiary gas input system is arranged on the outside of the combustion tube near the end, and the tertiary gas input system includes a main input pipe, a buffer chamber, a high-pressure input pipe and a low-pressure input pipe. The output end of the main input pipe is connected to the buffer chamber, and the high-pressure input pipe and the low-pressure input pipe are both connected to the buffer chamber. The output end of the high-pressure input pipe is connected between the reduced diameter section and the end of the combustion tube, and the output end of the low-pressure input pipe is connected to the reduced diameter section.

[0021] Preferably, a plurality of shunt tubes are provided on the annular protrusion, and output ends of the plurality of shunt tubes are distributed along the axial direction of the combustion tube.

[0022] On the other hand, the present invention proposes a boiler using a pulverized coal burner, wherein the pulverized coal burner is any of the pulverized coal burners based on hydrogen-based decomposition of ammonia and re-combustion as described above.

[0023] The beneficial effects of using the present invention are:

[0024] The pulverized coal burner based on hydrogen-based decomposition of ammonia and recombustion proposed in the present invention activates ammonia and inputs it into the combustion tube. The pulverized coal, oxygen and the activated mixed gas containing ammonia are simultaneously input into the combustion zone through the pulverized coal input tube arranged at the side wall of the combustion tube. Compared with the general pulverized coal input method of arranging the pulverized coal input tube at the position of the combustion zone corresponding to the combustion tube, the pulverized coal burner can significantly improve the burnout efficiency of the pulverized coal and reduce the amount of ash.

[0025] The guide device set at the position of coal powder input has two advantages. One is that it can change the direction of oxygen input, change the oxygen axial flow to swirl flow, change the swirl speed of oxygen by adjusting the direction of the guide vane, and then adjust the height of the combustion zone in the combustion tube, and finally change the combustion effect; the second is to introduce the coal powder into the combustion tube at the position with the fastest swirl speed, and pre-mix the coal powder, oxygen and the mixed gas containing ammonia. After verification by experimental data, the combustion effect of this mixed coal powder is significant due to the combustion effect of the coal powder introduced into the corresponding combustion zone position of the combustion tube.

[0026] The tertiary gas input system inputs one or a combination of reducing gas, protective gas or atomized water into the position between the reduced diameter section and the end of the combustion tube through the Bernoulli effect, which can form a gas-deficient area at the end of the combustion tube, provide a reducing environment, and reduce nitrogen oxide (NOx) emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of a pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion in the first embodiment of the present invention.

[0028] Figure 2 for Figure 1 Schematic diagram of the flow guide device.

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

[0030] Figure 4 It is a schematic diagram of a pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion in the second embodiment of the present invention.

[0031] Figure 5 It is a schematic diagram of a pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion in the third embodiment of the present invention.

[0032] Figure 6 The diagram shows the position of the combustion zone and the flame effect when different ammonia injection amounts are applied.

[0033] Reference numerals include:

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

[0035] 21-driving device, 22-guiding device, 221-lower plane bearing, 222-lower gear disc, 223-external tooth structure, 224-driving shaft, 225-upper plane bearing, 226-upper gear disc, 227-gear, 228-guide vane, 23-coal powder input pipe. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the technical solution more clear, the technical solution is further described in detail below in conjunction with specific implementation methods. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the technical solution.

[0037] Example 1

[0038] This embodiment proposes a pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion. This pulverized coal burner is based on hydrogen-based decomposition of ammonia and re-combustion to achieve ammonia activation and then burn ammonia. Specifically, this pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion includes: an ammonia activation device, which is used to activate ammonia and form a mixed gas through Brown gas combustion; a mixed gas delivery pipe 15, whose first end is connected to the ammonia activation device, and whose second end is the mixed gas output end; a combustion pipe 14, which is sleeved on the outside of the mixed gas delivery pipe 15, and the second end of the mixed gas delivery pipe 15 is arranged inside the combustion pipe 14, an oxygen input pipe 16, which is connected to the side wall of the combustion pipe 14 and communicated with the inside of the combustion pipe 14, and is used to deliver oxygen to the inside of the combustion pipe 14; a pulverized coal input pipe 23, which has a plurality of pulverized coal input pipes 23 and is connected to the side wall of the combustion pipe 14 in an annular array, and the pulverized coal input pipe 23 is adjacent to the second end of the mixed gas delivery pipe 15 and is located below the second end of the mixed gas delivery pipe 15.

[0039] Specifically, the ammonia activation equipment includes a heat increasing combustion tube 10. The heat increasing combustion tube 10 is a device required for ammonia activation. A Brownian gas input pipe 11 is arranged at the lower end of the heat increasing combustion tube 10. The side of the Brownian gas input pipe 11 has not only a first igniter 13, but also a first igniter 13, which is used to ignite Brownian gas inside the heat increasing combustion tube 10. An ammonia input pipe 12 is arranged inside the heat increasing combustion tube 10 at a position corresponding to the end of the Brownian gas input pipe 11. The ammonia input pipe 12 is slightly lower than the end of the Brownian gas input pipe 11.

[0040] As in the above structure, after the Brownian gas is input into the heating combustion tube 10, it can be ignited by the first igniter 13. In order to ensure that the hydrogen-oxygen mixture can effectively and stably burn in the combustion heating chamber, the molar ratio of the hydrogen-oxygen mixture made by electrolyzing water is H2:O2=2:1, and the flame propagation speed of the hydrogen-oxygen mixture is about 2.0-2.5m / s. According to the burner specifications and the demand for hydrogen by the ammonia decomposition rate, the caliber of the Brownian gas pipe output end needs to be optimized according to the outlet flow rate of the hydrogen-oxygen mixture, the ammonia flow rate and the pressure of 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 blow-out limit of the hydrogen flame to ensure that the hydrogen-oxygen mixture can burn stably. The ammonia flow rate in the combustion heating chamber will affect the pressure in the combustion heating chamber and the interference of the airflow disturbance on the flame combustion stability. The caliber of the Brownian gas pipe output port needs to be as large as possible while ensuring the stable combustion of the hydrogen-oxygen mixture as much as possible.

[0041] The above-mentioned hydrogen-based ammonia decomposition reburner is used to implement a hydrogen-based ammonia decomposition reburning method, which includes: introducing Brown's gas into a closed space and igniting the Brown's gas, introducing ammonia during the process of ignition of the Brown's gas, increasing the temperature of the ammonia and activating the ammonia during the combustion of the Brown's gas; drawing out the products of Brown's gas combustion and high-temperature ammonia and adding combustion-supporting gas, and igniting the above-mentioned mixed gas to achieve the effect of ammonia combustion.

[0042] The chemical reaction of ammonia and hydrogen combustion belongs to a chain reaction, which undergoes chain excitation, propagation and termination. The excitation of the chain requires the action of external factors (heat, high-energy molecular collision). Due to its high dissociation energy (NH bond dissociation energy is about 391kJ / mol), the combustion process of ammonia often faces the problems of low combustion efficiency and high ignition energy. Hydrogen (H2) is an efficient fuel. During its combustion, a series of active free radicals are generated. These free radicals have strong reactivity. The free 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 NH bond in the NH3 molecule, thereby reducing the activation energy of ammonia decomposition, but also accelerates the process of ammonia conversion into nitrogen and hydrogen.

[0043] The mixed gas formed by the combustion of ammonia and Brownian gas inside the heat-increasing combustion tube 10 is transported to the combustion tube 14 through the mixed gas delivery tube 15. An oxygen input tube 16 is provided near the lower end of the tube wall of the combustion tube 14. The oxygen input tube 16 enters the space between the mixed gas delivery tube 15 and the combustion tube 14. During this process, the input oxygen is affected and heated, and then transported to the end of the mixed gas delivery tube 15. During this process, the coal powder input tube 23 transports coal powder into the mixed gas, which is ignited by the second igniter 17. At this time, the ammonia combustion fully releases heat, and the coal powder in the mixed gas is also fully burned.

[0044] As a preferred example, Figure 1 As shown, a guide device 22 for swirling the input oxygen is also provided between the combustion tube 14 and the mixed gas delivery tube 15, and the guide device 22 is provided at a high position equal to the coal powder input tube 23. The guide device 22 provided at the position of coal powder input has two advantages. One is that it can change the direction of oxygen input, change the oxygen axial flow into swirl flow, and change the swirl speed of oxygen by adjusting the direction of the guide vane 228, thereby adjusting the height of the combustion zone in the combustion tube 14, and finally changing the combustion effect; the second is that the coal powder is introduced into the combustion tube 14 at the position with the fastest swirl speed, and the coal powder, oxygen and the mixed gas containing ammonia are pre-mixed. After verification by experimental data, the burnout effect of this mixed coal powder is significant due to the combustion effect of the coal powder introduced into the position corresponding to the combustion zone of the combustion tube 14.

[0045] like Figure 2 As shown, specifically, the guide device 22 includes a plurality of guide vanes 228, and the guide vanes 228 are arranged in an isotropic ring around the mixed gas delivery pipe 15. The inner end of the guide vane 228 is universally hinged to the outer wall of the mixed gas delivery pipe 15, and the position of the guide vane 228 on the outside of the combustion tube 14 is provided with a synchronous drive device 21, and the synchronous drive device 21 is connected to the outer end of the guide vane 228, and is used to drive the guide vane 228 to rotate synchronously at the same angle. The outer end of the guide vane 228 is connected to a drive shaft 224, which passes through the combustion tube 14. A gear 227 is installed at the end of the drive shaft 224 away from the reverse flow vane. Planar bearings are arranged above and below the corresponding gear 227 of the combustion tube 14, namely, an upper plane bearing 225 and a lower plane bearing 221. The plane bearing is a gear plate on the side facing the gear 227, and the gear plate is meshed with the gear 227. The synchronous drive device 21 also includes a drive device 21, which is transmission-connected to one of the gear plates to drive the gear plate to rotate. The upper gear plate 226 and the lower gear plate 222 coordinate the gear 227 to rotate synchronously.

[0046] In this embodiment, the driving device 21 drives the tooth structure to rotate through the output shaft, and drives the lower toothed disc 222 to rotate by driving the outer toothed structure 223 in the lower plane bearing 221. Since the lower toothed disc 222 and the gear 227 are meshed with each other, all the gears 227 can be driven to rotate synchronously. 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, the axial flow moves upward, and after being guided by the flow guide device 22, it is deflected to a swirl.

[0047] Combination Figure 3 As shown, 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 pipe 23 is the same as the swirl direction of the oxygen. When the oxygen forms a significant swirl effect after passing through the guide device 22, the pulverized coal can also form a fast and large-angle swirl effect when the pulverized coal is input at this time.

[0048] A second igniter 17 is provided at the end of the mixed gas delivery pipe 15. The second igniter 17 is used to ignite the activated ammonia. When the pulverized coal passes through the burning ammonia in a fast and large-angle swirl state, the pulverized coal is fully burned after entering the combustion zone.

[0049] If the input amount of ammonia is adjusted under certain conditions, for example, when the mixed ammonia ratio is 17%-19%, ammonia can achieve the effect of full combustion. If the calorific value needs to be reduced and the input ratio of ammonia is reduced, the position of the combustion zone can be lowered. At this time, the guide device 22 is adjusted to increase the inclination angle of the guide vane 228. At this time, the combustion zone is lowered, making the combustion calorific value controllable. The effect is as follows: Figure 6 shown.

[0050] The pulverized coal burner based on hydrogen-based decomposition of ammonia and recombustion proposed in the present invention activates ammonia and inputs it into the combustion tube 14. The pulverized coal, oxygen and the activated mixed gas containing ammonia are simultaneously input into the combustion zone through the pulverized coal input pipe 23 arranged at the side wall of the combustion tube 14. Compared with the general pulverized coal input method of setting the pulverized coal input pipe 23 at the position of the combustion zone corresponding to the combustion zone of the combustion tube 14, the pulverized coal burner can significantly improve the combustion efficiency of the pulverized coal and reduce the amount of ash.

[0051] One major effect of the pulverized coal combustion in this embodiment is that the pulverized coal channels are arranged at the surrounding positions, for example, the pre-activation equipment of ammonia is arranged through a simple structure, and the ammonia cannot be combined with the pulverized coal input after pre-activation. At the same time, changing the position of the combustion zone is conducive to reducing nitrogen oxide (NOx) emissions.

[0052] Example 2

[0053] like Figure 4 As shown, the pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion in this embodiment has the same basic structure as the pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion in Example 1, except that a guide plate 19 is provided at the end of the combustion tube 14. The guide plate 19 is used to guide the airflow radially inward, forming a reduced diameter section 18 around the combustion zone, generating a gas-deficient area, and achieving the purpose of strengthening the combustion of pulverized coal and reducing the generation of NOx.

[0054] Example 3

[0055] like Figure 5 As shown, the pulverized coal burner based on hydrogen-based decomposition of ammonia recombustion in this embodiment has the same basic structure as the pulverized coal burner based on hydrogen-based decomposition of ammonia recombustion 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, the inner wall of the burner has an annular protrusion structure, and the section where the annular protrusion structure is located is a reduced diameter section 18, and the reduced diameter section 18 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 arranged near the end of the combustion tube 14. The tertiary gas input system 110 includes a main input pipe 1101, a buffer chamber 1102, a high pressure input pipe 1103 and a low pressure input pipe 1104. The output end of the main input pipe 1101 is connected to the buffer chamber 1102. The high pressure input pipe 1103 and the low pressure input pipe 1104 are both connected to the buffer chamber 1102. The output end of the high pressure input pipe 1103 is connected between the reduced diameter section 18 and the end of the combustion tube 14. The output end of the low pressure input pipe 1104 is connected to the reduced diameter section 18. A plurality of shunt pipes 1105 are arranged on the annular protrusion, and the output ends of the plurality of shunt pipes 1105 are 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, at a position between the reduced diameter section 18 and the end of the combustion tube 14 through the Bernoulli effect, thereby forming a gas-deficient area at the end of the combustion tube 14, providing a reducing environment and reducing nitrogen oxide (NOx) emissions.

[0059] In this embodiment, in the first scheme, pressurized nitrogen is input through the main input pipe 1101, and after the nitrogen is released in the buffer chamber 1102, pressurized nitrogen is simultaneously input to the high-pressure input pipe 1103 and the low-pressure input pipe 1104. Since the pressure of the gas inside the combustion tube 14 on the inner wall of the combustion tube 14, the pressure at the reduced diameter section 18 is less than the pressure of the tube wall of the combustion tube 14 above it, most of the gas is discharged through the diverter pipe 1105 at the reduced diameter section 18, and a small part is discharged from the low-pressure input pipe 1104, so a depleted gas zone is generated around and above the burner. Nitrogen oxides (NOx) formed by the combustion of ammonia and oxygen are reduced by the coal powder residue to reduce the generation of nitrogen oxides (NOx).

[0060] In the second embodiment, after the mixed fluid of nitrogen and water is input through the main input pipe 1101, the water and ammonia gas enter the buffer chamber 1102 synchronously, and the water is atomized and discharged through the shunt pipe 1105. At this time, an atomizing nozzle is provided at the end of the shunt pipe 1105. Nitrogen is discharged through the low-pressure input pipe 1104, and the atomized water is separated into H radicals and OH radicals after passing through the combustion zone. At the same time, due to the effect of nitrogen, a gas-deficient zone is generated at the upper part of the combustion zone, and the H radical reduces nitrogen oxides (NOx) under high temperature environment.

[0061] In this embodiment, since the high-pressure input pipe 1103 and the low-pressure input pipe 1104 are set at different positions, the tertiary gas input system 110 has different pressure differences in the reduced diameter section 18 and the expanded section through the Bernoulli effect. The fluid output by the tertiary gas input system 110 can automatically adjust the ratio of the fluid input by the high-pressure input pipe 1103 and the low-pressure input pipe 1104 according to the different fluid flow rates in the combustion tube 14, so as to achieve the effect of widely adjusting the combustion effect in the combustion zone.

[0062] The present invention also proposes a boiler, which uses the above-mentioned pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion, and also inherits the advantages of the above-mentioned pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion.

[0063] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, many changes can be made in the specific implementation methods and application scopes based on the ideas of the present technical content. As long as these changes do not deviate from the concept of the present invention, they all fall within the scope of protection of this patent.

Claims

1. A pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion, characterized in that: 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, a first end of which is connected to the ammonia activation device, and a 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, and used for delivering oxygen to the interior of the combustion tube; There are several pulverized coal input pipes connected to the side wall of the combustion pipe in an annular array. The pulverized coal 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.

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

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

4. The pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion according to claim 3 is characterized in that: The guide device includes a plurality of guide vanes, which are arranged in an isohymetric ring around the mixed gas delivery pipe. The inner ends of the guide vanes are universally hinged to the outer walls of the mixed gas delivery pipe. The outside of the combustion tube is provided with a synchronous driving device at the position corresponding to the guide vanes. The synchronous driving device 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 gear of the combustion tube. The plane bearing is a geared disc facing the gear, and the geared disc is meshed 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 re-combustion according to claim 1 is characterized in that: The end of the combustion tube is evenly distributed along the circumferential direction with a plurality of guide plates with adjustable outward opening angles.

7. The pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion according to claim 1 is characterized in that: 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.

8. The pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion according to claim 7 is characterized in that: A tertiary gas input system is arranged on the outside of the combustion tube near the end, and the tertiary gas input system includes a main input pipe, a buffer chamber, a high-pressure input pipe and a low-pressure input pipe. The output end of the main input pipe is connected to the buffer chamber, and the high-pressure input pipe and the low-pressure input pipe are both connected to the buffer chamber. The output end of the high-pressure input pipe is connected between the reduced diameter section and the end of the combustion tube, and the output end of the low-pressure input pipe is connected to the reduced diameter section.

9. The pulverized coal burner based on hydrogen-based decomposition of ammonia and re-combustion according to claim 8, characterized in that: A plurality of shunt pipes are arranged on the annular protrusion, and the output ends of the plurality of shunt pipes are distributed along the axial direction of the combustion tube.

10. 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 re-combustion as described in any one of claims 1 to 9.

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