Wide-load dust removal and denitration system
By designing a wide load dust removal and denitrification system in a coal-fired boiler, using components such as flue wind speed balance baffle, deflux dust collector and ammonia spray grille, the flue blockage and catalyst wear problems are solved, and the flue gas uniformity is achieved The blending of flow and ammonia gas improves the denitrification efficiency and meets the denitrification needs of coal-fired boilers under flexible adjustment.
Patent Information
- Application Number
- CN202411531640.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-30
- Publication Date
- 2024-12-27
AI Technical Summary
When flexible adjustment is made, existing coal-fired boilers are prone to flue blockage, catalyst wear and ammonia escape exceeding the standard, resulting in poor denitrification effect and cannot meet the needs of unit load flexibility adjustment.
A wide load dust removal and denitrification system was designed, including boiler tail flue, T-type flue and denitrification reactor, by setting up flue wind speed balance baffle, deflux dust collector, bar-shaped gate deflector, ammonium spray grid The gate and wind turbine mixer, as well as the flue gas flow guide, realize the uniform flow of flue gas and the uniform blending of ammonia and flue gas, avoid smoke accumulation and catalyst wear, and improve denitrification efficiency.
It effectively avoids flue blockage and catalyst wear, reduces the risk of ammonia escape, improves denitrification efficiency, and meets the unit's denitrification needs under wide load operation.
Smart Images
Figure CN119186253A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of denitration, and in particular to a wide-load dust removal and denitration system. Background Art
[0002] In recent years, the installed capacity of renewable energy power generation has been increasing, resulting in increasingly frequent flexibility adjustments of coal-fired boilers, especially at low loads where the flue gas carrying capacity is poor, which can easily cause ash accumulation in the flue and wear and blockage of catalysts. What's worse, the flue gas fluctuations caused by flexibility adjustment are large, and conventional ammonia mixing equipment cannot meet the flexibility adjustment of the unit load, resulting in excessive ammonia escape from the denitrification reactor, poor denitrification effect, and blockage of the air preheater.
[0003] Therefore, there is an urgent need for a wide-load dust removal and denitrification system to solve the above problems. Summary of the invention
[0004] The purpose of the present invention is to solve the problems that, when the existing coal-fired boiler is adjusted flexibly, low-speed flue gas easily causes flue blockage and increased power consumption of the unit; high-ash operation of the unit easily wears and blocks the catalyst, bringing risks to the safe operation of the denitrification device; and the flue gas fluctuations caused by flexible adjustment are large, and conventional ammonia mixing equipment cannot meet the flexible adjustment of the unit load, resulting in excessive ammonia escape from the denitrification reactor and poor denitrification effect. A wide-load dust removal and denitrification system is provided.
[0005] The technical solution of the present invention is as follows: A wide-load dust removal and denitration system, comprising a boiler tail flue, a T-shaped flue and a denitration reactor; The T-shaped flue includes a horizontal flue and a vertical flue vertically connected to the horizontal flue, the smoke inlet of the horizontal flue is connected to the smoke outlet of the boiler tail flue, one or more flue wind speed balancing baffles are arranged inside the horizontal flue, the smoke outlet of the vertical flue is connected to the smoke inlet of the denitrification reactor, and a flue gas deflector is arranged at the connecting point, a strip grid deflector is arranged at the connecting port between the vertical flue and the horizontal flue, one or more baffle dust collectors are arranged inside the horizontal flue below the strip grid deflector, the horizontal flue is connected to an ash storage bin below the baffle dust collector, an ammonia injection grid and a plurality of wind wheel ammonia mixers are arranged inside the vertical flue above the strip grid deflector, and at least one catalyst layer is arranged inside the denitrification reactor.
[0006] Preferably, a plurality of the flue wind speed balancing baffles are arranged at preset intervals in the horizontal and vertical directions inside the horizontal flue.
[0007] Preferably, the total height b of the plurality of flue wind speed balance baffles arranged at intervals in the vertical direction is equal to the vertical height m of the interior of the horizontal flue. .
[0008] Preferably, the flue wind speed balancing baffle comprises an upper wind baffle, a sleeve, a core shaft and a lower wind baffle, the upper wind baffle and the lower wind baffle are installed on the sleeve in relative directions, the sleeve is rotatably mounted on the core shaft, and one end of the core shaft is vertically connected to the side of the horizontal flue.
[0009] Preferably, the height of the lower wind shield plate is greater than that of the upper wind shield plate; and a plurality of ash discharge holes are provided on the surface of the sleeve.
[0010] Preferably, the deflector dust collector comprises a plurality of right-angle deflector dust removal plates, and the plurality of right-angle deflector dust removal plates are arranged in a stepped manner at preset angles inside the horizontal flue.
[0011] Preferably, the preset angle is a=arctan(m / n), wherein m is the vertical height inside the horizontal flue, and n is the horizontal length inside the vertical flue.
[0012] Preferably, the spacing c between two adjacent baffle dust collectors is equal to the horizontal length n inside the vertical flue. .
[0013] Preferably, the strip grid guide comprises a plurality of strip plates arranged at a preset interval, wherein the preset interval is a height d of the strip plates. The plate surfaces of the plurality of strip plates are arranged parallel to the flow direction of the smoke.
[0014] Preferably, the horizontal arrangement interval of the plurality of wind wheel ammonia mixers is equal to n of the horizontal length of the vertical flue. ; The vertical distance between the ammonia injection grid and the multiple wind wheel ammonia mixers is 300mm-500mm.
[0015] Preferably, the wind wheel ammonia mixer includes wind wheel blades, a wind sleeve and a wind wheel shaft, a plurality of the wind wheel blades are installed on the wind sleeve at preset intervals, the wind sleeve is rotatably mounted on the wind wheel shaft, and one end of the wind wheel shaft is vertically connected to the side of the vertical flue.
[0016] Preferably, two adjacent wind wheel blades are arranged in a cross-staggered manner; and a plurality of ash outlet holes are opened on the surface of the wind sleeve.
[0017] Preferably, the ammonia injection grid includes an ammonia supply main pipe and an ammonia injection branch pipe, the ammonia supply main pipe is arranged outside the vertical flue, one end of a plurality of ammonia injection branch pipes is connected to the ammonia supply main pipe, and the other end extends to the interior of the vertical flue, and a plurality of injection holes are opened on the ammonia injection branch pipes.
[0018] Preferably, the smoke deflector comprises a plurality of smoke deflector wings arranged at intervals, and the smoke deflector wings comprise a deflector fin and a beak connected to one end of the deflector fin.
[0019] Preferably, the guide fin is an obtuse-angled guide fin, and the beak is a right-angled beak, and the long side of the right-angled beak is connected to one end of the obtuse-angled guide fin close to the denitration reactor.
[0020] Preferably, a rectifying grid is provided inside the denitration reactor above the catalyst layer.
[0021] Preferably, a straight plate flow guide is provided in the flue of the denitration reactor at the front end of the rectifier grid, and the straight plate flow guide includes a plurality of straight plates arranged obliquely relative to the flue gas flow direction.
[0022] Preferably, the boiler tail flue comprises a straight tube flue and an inclined tube flue connected to the straight tube flue, and a smoke outlet of the inclined tube flue is connected to a smoke inlet of the horizontal flue.
[0023] According to the above technical scheme, based on the wide-load dust removal and denitrification system, by setting up the boiler tail flue, the boiler flue gas can be diverted into the horizontal flue, and further by setting up a flue wind speed balancing baffle in the horizontal flue, when the boiler is under high load, a large amount of flue gas can blow the flue wind speed balancing baffle into a horizontal state, and when the load is reduced, the flue wind speed balancing baffle will gradually return to a vertical state as the airflow decreases, forcing the flue gas to flow mainly through the bottom of the horizontal flue smoke inlet, ensuring that the flue gas at the bottom of the horizontal flue smoke inlet is always flowing at a high flow rate, which can fully carry the smoke and dust, and avoid the accumulation of smoke and dust on the bottom surface of the horizontal flue smoke inlet, resulting in smoke blockage and increased power consumption of the unit; and further by setting up a vertical flue at the connection between the vertical flue and the horizontal flue. A strip grid flow guide, and a baffle dust collector and an ash storage bin are arranged below the strip grid flow guide. When the flue gas carrying dust reaches the baffle dust collector area, the smoke dust can fall into the ash storage bin due to inertia and the obstruction of the baffle dust collector and the strip grid flow guide, and the low-ash flue gas will go up after being evenly flowed through the strip grid flow guide, thereby effectively avoiding the high dust content in the flue gas from wearing out the catalyst and clogging the catalyst, which brings risks to the safe operation of the denitrification device; and further, by arranging an ammonia spray grid and multiple wind wheel ammonia mixers, a vortex street of air flow can be formed based on turbulence to achieve uniform mixing of ammonia and low-ash flue gas, thereby avoiding excessive ammonia escape; and further, by arranging a flue gas flow guide, the flue gas can react with the catalyst more evenly, thereby effectively improving the denitrification efficiency of the flue gas. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Figure 1 It is a schematic diagram of the structure of a wide-load dust removal and denitrification system; Figure 2 It is a structural schematic diagram of the flue wind speed balance damper of the wide-load dust removal and denitrification system; Figure 3 It is a schematic diagram of the structure of the right-angle baffle dust collector plate of the baffle dust collector of the wide-load dust removal and denitrification system; Figure 4 It is a schematic diagram of the structure of the strip plate of the strip grid guide of the wide-load dust removal and denitrification system; Figure 5 It is a schematic diagram of the structure of the wind wheel ammonia mixer of the wide load dust removal and denitrification system; Figure 6 It is a schematic diagram of the structure of the ammonia injection grid of the wide-load dust removal and denitrification system; Figure 7 It is a schematic diagram of the structure of the flue gas guide wing of the flue gas guide of the wide-load dust removal and denitrification system; Figure 8 It is a schematic diagram of the three-dimensional structure of a wide-load dust removal and denitrification system in a specific implementation manner.
[0025] Description of Reference Numerals 1. Boiler tail flue; 11. Straight flue; 12. Oblique flue; 2. Flue wind speed balance baffle; 21. Upper baffle; 22. Sleeve; 23. Mandrel; 24. Lower baffle; 3. Horizontal flue; 4. Ash discharge port; 5. Ash storage bin; 6. Baffle dust collector; 61. Right-angle baffle dust collector; 7. Strip grid guide; 71. Strip plate; 8. Vertical flue; 9. Wind wheel Ammonia mixer; 91, wind wheel blades; 92, wind sleeve; 93, wind wheel shaft; 10, ammonia injection grid; 101, ammonia supply main pipe; 102, ammonia injection branch pipe; 13, flue gas deflector; 131, flue gas deflector wing; 1311, deflector wing; 1312, eagle beak; 14, straight plate deflector; 15, denitration reactor; 16, rectifier grid; 17, catalyst layer; 18, clean smoke outlet. DETAILED DESCRIPTION
[0026] The specific implementation of the embodiment of the present invention is described in detail below. It should be understood that the specific implementation described here is only used to illustrate and explain the embodiment of the present invention, and is not used to limit the embodiment of the present invention.
[0027] The present invention provides a wide load dust removal and denitrification system, such as Figure 1-8 As shown, the wide-load dust removal and denitration system includes a boiler tail flue 1, a T-shaped flue and a denitration reactor 15; The T-shaped flue includes a horizontal flue 3 and a vertical flue 8 vertically connected to the horizontal flue 3, the smoke inlet of the horizontal flue 3 is connected to the smoke outlet of the boiler tail flue 1, one or more flue wind speed balancing baffles 2 are arranged inside the horizontal flue 3, the smoke outlet of the vertical flue 8 is connected to the smoke inlet of the denitrification reactor 15, and a flue gas deflector 13 is arranged at the connecting portion, a strip grid deflector 7 is arranged at the connecting port between the vertical flue 8 and the horizontal flue 3, one or more baffle dust collectors 6 are arranged inside the horizontal flue 3 below the strip grid deflector 7, the horizontal flue 3 is connected to an ash storage bin 5 below the baffle dust collector 6, an ammonia injection grid 10 and a plurality of wind wheel ammonia mixers 9 are arranged inside the vertical flue 8 above the strip grid deflector 7, and at least one catalyst layer 17 is arranged inside the denitrification reactor 15.
[0028] According to the above technical scheme, based on the wide-load dust removal and denitrification system, by setting the boiler tail flue 1, the boiler flue gas can be diverted into the horizontal flue 3, and by further setting the flue wind speed balancing baffle 2 in the horizontal flue 3, when the boiler is under high load, a large amount of flue gas can blow the flue wind speed balancing baffle 2 into a horizontal state, and when the load is reduced, the flue wind speed balancing baffle 2 will gradually return to a vertical state as the airflow decreases, forcing the flue gas to flow mainly through the bottom of the horizontal flue 3 smoke inlet, ensuring that the flue gas at the bottom of the horizontal flue 3 smoke inlet is always flowing at a high flow rate, which can fully carry the smoke and dust, and avoid the smoke and dust from accumulating on the bottom surface of the horizontal flue 3 smoke inlet, resulting in smoke blockage and increased power consumption of the unit; and further by setting a strip at the connection between the vertical flue 8 and the horizontal flue 3 A strip grid deflector 7 is provided, and a baffle dust collector 6 and an ash storage bin 5 are provided below the strip grid deflector 7. When the flue gas carrying dust reaches the baffle dust collector 6 area, the smoke can fall into the ash storage bin 5 under the inertia and the obstruction of the baffle dust collector 6 and the strip grid deflector 7, and the low-ash flue gas goes up after being evenly flowed through the strip grid deflector 7, thereby effectively avoiding the high dust content in the flue gas from wearing the catalyst and clogging the catalyst, which brings risks to the safe operation of the denitrification device; and further, by providing an ammonia spray grid 10 and a plurality of wind wheel ammonia mixers 9, a uniform mixing of ammonia and low-ash flue gas can be achieved based on the formation of an airflow vortex street based on turbulence, thereby avoiding excessive ammonia escape, and further by providing a flue gas deflector 13, the flue gas can react with the catalyst more evenly, thereby effectively improving the denitrification efficiency of the flue gas.
[0029] In the wide-load dust removal and denitrification system of the present invention, preferably, a plurality of flue wind speed balancing baffles 2 are arranged at preset intervals in the horizontal and vertical directions inside the horizontal flue 3, and the specific arrangement density is determined according to the horizontal length and vertical height of the horizontal flue 3. Preferably, the total height b of the plurality of flue wind speed balancing baffles 2 arranged at intervals in the vertical direction is equal to the vertical height m inside the horizontal flue 3. , and in the horizontal direction, they are arranged at preset intervals, and the specific intervals may be 3000mm-7000mm, thereby more effectively preventing smoke from gathering on the bottom surface of the horizontal flue 3.
[0030] In a specific embodiment, the flue wind speed balancing baffle 2 includes an upper wind baffle 21, a sleeve 22, a core shaft 23 and a lower wind baffle 24, wherein the upper wind baffle 21 and the lower wind baffle 24 are mounted on the sleeve 22 at 180° relative to each other, the sleeve 22 is rotatably mounted on the core shaft 23, and one end of the core shaft 23 is vertically connected to the side of the horizontal flue 3, so that under the action of flue gas, the upper wind baffle 21, the sleeve 22 and the lower wind baffle 24 can rotate around the core shaft 23, thereby achieving the balance of the flue wind speed. Preferably, the upper wind baffle 21 and the lower wind baffle 24 can be a plate, which is divided into upper and lower parts by the sleeve 22.
[0031] In a more specific embodiment, the upper wind shield 21, the sleeve 22, the core shaft 23 and the lower wind shield 24 of the flue wind speed balancing baffle 2 are all made of wear-resistant steel to ensure sufficient structural strength and suitability for flue gas environments.
[0032] In a preferred embodiment, the height of the lower wind shield 24 is greater than the height of the upper wind shield 21. Specifically, the height of the lower wind shield 24 is 500mm-800mm, and the height of the upper wind shield 21 is 100mm-500mm, so that the lower wind shield 24 can balance the gravity of the upper wind shield 21 while better balancing the flue gas flow rate, thereby making the flue gas flow rate balance baffle 2 always vertical in the initial state, and can gradually restore the initial state when the flue gas flow rate weakens. In another preferred embodiment, a plurality of ash discharge holes are opened on the surface of the sleeve 22, so as to facilitate the discharge of accumulated ash from the sleeve 22.
[0033] In the wide-load dust removal and denitrification system described in the present invention, preferably, the baffle dust collector 6 includes a plurality of right-angle baffle dust removal plates 61, and the plurality of right-angle baffle dust removal plates 61 are arranged in a stepped manner at preset angles inside the horizontal flue 3, so as to better cooperate with the strip grid deflector 7 to achieve dust removal of the flue gas.
[0034] Further preferably, the preset angle is a=arctan(m / n), wherein m is the vertical height inside the horizontal flue, and n is the horizontal length inside the vertical flue, so as to further better remove dust from the flue gas.
[0035] In another preferred embodiment, the spacing c between two adjacent baffle dust collectors 6 is equal to the horizontal length n inside the vertical flue. , thereby further improving the dust removal effect on the flue gas. Among them, the number of right-angle baffle dust removal plates 61 included in two adjacent baffle dust collectors 6 can be the same or different, and is specifically set according to actual needs.
[0036] In a specific embodiment, the short fold of the right-angle baffle dust removal plate 61 is 50mm-100mm long, the long fold is 300mm-800mm long, and the interval c between two adjacent baffle dust collectors 6 is 100mm-200mm, so as to better remove dust from the flue gas. More specifically, the right-angle baffle dust removal plate 61 is made of wear-resistant steel to ensure sufficient structural strength and suitability for flue gas environments. Among them, an ash storage bin 5 is provided below the long fold, and the ash storage bin 5 is funnel-shaped, and an ash discharge port 4 is provided at the bottom to facilitate ash discharge.
[0037] In the wide-load dust removal and denitrification system of the present invention, preferably, the strip grid deflector 7 includes a plurality of strip plates 71 arranged at preset intervals, and the preset intervals are the height d of the strip plates 71. The plate surfaces of the plurality of strip plates 71 are arranged parallel to the flow direction of the flue gas, so that they can cooperate with the baffle dust collector 6 to better remove dust from the flue gas, and can also make the flue gas flow evenly before entering the subsequent denitration device, thereby improving the denitration effect of the denitration device on the flue gas. In a specific embodiment, the height d of the strip plate 71 is 200-500mm and the thickness is 5-7mm. In another specific embodiment, the strip plate 71 is made of wear-resistant steel to ensure that it has sufficient structural strength and is suitable for the flue gas environment.
[0038] In the wide-load dust removal and denitrification system of the present invention, preferably, the horizontal arrangement interval of the plurality of wind wheel ammonia mixers 9 is equal to the horizontal length n of the vertical flue 8. , thereby further effectively improving the uniformity of ammonia and low-ash flue gas mixing and avoiding excessive ammonia escape. In another preferred embodiment, the ammonia injection grid 10 is arranged on the upper part or lower part of the plurality of wind wheel ammonia mixers 9, and the vertical distance between the two is 300mm-500mm, so as to further improve the uniformity of ammonia and low-ash flue gas mixing.
[0039] In a specific embodiment, the wind wheel ammonia mixer 9 includes a wind wheel blade 91, a wind sleeve 92 and a wind wheel shaft 93, a plurality of the wind wheel blades 91 are installed on the wind sleeve 92 at preset intervals, the wind sleeve 92 is rotatably mounted on the wind wheel shaft 93, and one end of the wind wheel shaft 93 is vertically connected to the side of the vertical flue 8. In actual application, the low-ash flue gas after dust removal and flow equalization by the baffle dust collector 6 and the strip grid guide 7 rises along the vertical flue 8, and drives the wind wheel blades 91 and the wind sleeve 92 of the plurality of wind wheel ammonia mixers 9 to rotate at high speed around the wind wheel shaft 93, so that the wind wheel blades 91 strongly disturb the airflow to form an airflow vortex street, strengthen the mixing with the ammonia from the ammonia spray grid 10, and then effectively improve the uniformity of the mixing of ammonia and low-ash flue gas. In a more specific embodiment, Figure 5 As shown, the two adjacent wind wheel blades 91 are arranged in a staggered manner, preferably in a cross-staggered manner, so that the flue gas can better drive the wind wheel blades 91 to rotate, thereby improving the uniformity of the mixing of ammonia and low-ash flue gas. In another specific embodiment, a plurality of ash outlet holes are provided on the surface of the wind sleeve 92, so as to facilitate the discharge of accumulated ash from the wind sleeve 92. The height of the wind wheel blade 91 is 200mm-450mm, and the length is 500mm-800mm. The wind wheel blades 91, wind sleeve 92 and wind wheel shaft 93 of the wind wheel ammonia mixer 9 are all made of wear-resistant steel to ensure sufficient structural strength and suitability for flue gas environments.
[0040] In the wide-load dust removal and denitrification system described in the present invention, preferably, the ammonia injection grid 10 includes an ammonia supply main pipe 101 and an ammonia injection branch pipe 102, the ammonia supply main pipe 101 is arranged outside the vertical flue 8, one end of a plurality of ammonia injection branch pipes 102 is connected to the ammonia supply main pipe 101, and the other end extends to the interior of the vertical flue 8, and a plurality of injection holes are provided on the ammonia injection branch pipes 102, so that in actual application, ammonia can be evenly introduced into the vertical flue 8 and evenly mixed with the low-ash flue gas. In another preferred embodiment, the diameter of the ammonia supply main pipe 101 is 30-50 times the diameter of the ammonia injection branch pipe 102, the spacing between two adjacent ammonia injection branch pipes 102 is generally 800mm-1500mm, the spacing between two adjacent injection holes on the ammonia injection branch pipe 102 is 200mm-500mm, and the injection gas velocity is 15m / s-25m / s, so as to better mix with the flue gas.
[0041] In the wide load dust removal and denitrification system of the present invention, preferably, Figure 7As shown, the flue gas deflector 13 includes a plurality of flue gas deflector wings 131 arranged at intervals, and the flue gas deflector 131 includes a deflector fin 1311 and a beak 1312 connected to one end of the deflector fin 1311, so that by further deflecting the flue gas after uniform mixing, the flue gas can react more uniformly with the catalyst, thereby effectively improving the denitration efficiency of the flue gas. Further preferably, the deflector fin 1311 is an obtuse-angled deflector fin, and the beak 1312 is a right-angled beak, and the long side of the right-angled beak is connected to one end of the obtuse-angled denitration reactor 15, so that the flue gas can react more uniformly with the catalyst, thereby effectively improving the denitration efficiency of the flue gas; and the beak 1312 structure on the flue gas deflector fin 131 can also promote the fly ash accumulated on the deflector fin 1311 to be evenly distributed in the flue gas, thereby further avoiding clogging of the catalyst and extending the service life of the catalyst. In a specific embodiment, the spacing between two adjacent smoke guide wings 131 is 500mm-1000mm. In another specific embodiment, the smoke guide wings 131 are made of wear-resistant steel with a thickness of 3-10mm to ensure sufficient structural strength and suitability for smoke environments.
[0042] In the wide-load dust removal and denitration system described in the present invention, preferably, the denitration reactor 15 is provided with a rectifying grid 16 inside the catalyst layer 17, so as to further rectify the flue gas so that it can react with the catalyst more evenly, thereby effectively improving the denitration efficiency of the flue gas. In another preferred embodiment, the denitration reactor 15 is provided with a straight plate guide 14 in the flue at the front end of the rectifying grid 16, and the straight plate guide 14 includes a plurality of straight plates inclined relative to the flue gas flow direction, so that the flue gas can react with the catalyst more evenly, thereby effectively improving the denitration efficiency of the flue gas. Among them, the number of layers of the catalyst layer 17 inside the denitration reactor 15 is set according to actual needs, preferably 2-5 layers.
[0043] In the wide-load dust removal and denitrification system described in the present invention, preferably, the boiler tail flue 1 includes a straight tube flue 11 and an inclined tube flue 12 connected to the straight tube flue 11, and the smoke outlet of the inclined tube flue 12 is connected to the smoke inlet of the horizontal flue 3, so that while introducing the boiler flue gas, the smoke outlet can be made smaller based on the inclined tube flue 12, and then better used in conjunction with the flue wind speed balance baffle 2 in the horizontal flue 3 to avoid dust accumulation on the inner bottom of the horizontal flue 3.
[0044] The present invention will be described in detail below through examples, but the protection scope of the present invention is not limited thereto.
[0045] Example 1 Use Figure 1-8The wide-load dust removal and denitration system shown is implemented, specifically, the wide-load dust removal and denitration system includes a boiler tail flue 1, a T-shaped flue and a denitration reactor 15; The T-shaped flue includes a horizontal flue 3 and a vertical flue 8 vertically connected to the horizontal flue 3, the smoke inlet of the horizontal flue 3 is connected to the smoke outlet of the boiler tail flue 1, one or more flue wind speed balancing baffles 2 are arranged inside the horizontal flue 3, the smoke outlet of the vertical flue 8 is connected to the smoke inlet of the denitrification reactor 15, and a flue gas deflector 13 is arranged at the connecting portion, a strip grid deflector 7 is arranged at the connecting port between the vertical flue 8 and the horizontal flue 3, one or more baffle dust collectors 6 are arranged inside the horizontal flue 3 below the strip grid deflector 7, the horizontal flue 3 is connected to an ash storage bin 5 below the baffle dust collector 6, an ammonia injection grid 10 and a plurality of wind wheel ammonia mixers 9 are arranged inside the vertical flue 8 above the strip grid deflector 7, and three catalyst layers 17 are arranged inside the denitrification reactor 15.
[0046] In actual application, the flue gas to be denitrified from the boiler enters through the boiler tail flue 1, and then the flue gas entering the boiler tail flue 1 maintains a high flow rate under the acceleration of the inclined tube flue 12, the horizontal flue 3 and the flue wind speed balance baffle 2, and then the smoke falls into the ash storage bin 5 under the inertia and the blocking of the baffle dust collector 6 and the strip grid deflector 7. The low-ash flue gas flows evenly through the strip grid deflector 7 and then goes up to the ammonia injection grid 10 and multiple wind wheel ammonia mixers 9 for even mixing of ammonia and low-ash flue gas. Then the flue gas carrying ammonia enters the flue gas deflector 13 for secondary equalization of the flue gas. The flue gas after the secondary equalization enters the denitrification reactor 15, completes the denitrification process of the flue gas under the action of the three-layer catalyst layer 17, and is finally discharged through the clean smoke outlet 18.
[0047] After testing, it is found that the wide-load dust removal and denitrification system described in the present invention can effectively avoid the accumulation of smoke on the bottom of the horizontal flue, which leads to flue blockage and increased power consumption of the unit, compared with the prior art solution of directly mixing boiler flue gas and ammonia without dust removal and then sending the mixture into the denitrification reactor for denitrification. It can also avoid the high dust content in the flue gas that wears out the catalyst and clogs the catalyst, which poses a risk to the safe operation of the denitrification device, and achieves effective and uniform mixing of ammonia and low-ash flue gas, as well as effective diversion of the flue gas after mixing, thereby effectively improving the denitrification efficiency of the flue gas under a wide-load operating environment.
[0048] Example 2 Refer to Example 1, except that the six flue wind speed balancing baffles 2 are arranged at preset intervals in the horizontal and vertical directions inside the horizontal flue 3; the total height b of the two flue wind speed balancing baffles 2 arranged at intervals in the vertical direction is equal to the vertical height m of the horizontal flue 3. The flue wind speed balancing baffle 2 includes an upper wind shield 21, a sleeve 22, a core shaft 23 and a lower wind shield 24. The upper wind shield 21 and the lower wind shield 24 are installed on the sleeve 22 at 180° relative directions. The sleeve 22 is rotatably mounted on the core shaft 23. One end of the core shaft 23 is vertically connected to the side of the horizontal flue 3. The height of the lower wind shield 24 is greater than that of the upper wind shield 21. A plurality of ash discharge holes are provided on the surface of the sleeve 22.
[0049] After testing, it is found that the wide-load dust removal and denitrification system described in the present invention can further effectively prevent smoke and dust from gathering on the bottom of the horizontal flue, causing flue blockage and increased power consumption of the unit, compared with the solution in Example 1, while improving the dust removal effect on the flue gas.
[0050] Example 3 Refer to Example 2 for implementation. The difference is that the deflector dust collector 6 includes a plurality of right-angle deflector dust collecting plates 61, and the plurality of right-angle deflector dust collecting plates 61 are arranged in a stepped manner at a preset angle inside the horizontal flue 3; the preset angle is a=arctan(m / n), wherein m is the vertical height inside the horizontal flue, and n is the horizontal length inside the vertical flue; the setting interval c between two adjacent deflector dust collectors 6 is the horizontal length n inside the vertical flue. The strip grid guide 7 comprises a plurality of strip plates 71 arranged at a preset interval, wherein the preset interval is the height d of the strip plates 71. The plate surfaces of the plurality of strip plates 71 are arranged parallel to the flow direction of the smoke.
[0051] After testing, it is found that the wide-load dust removal and denitrification system described in the present invention, compared with the scheme in Example 2, can further effectively avoid the high dust content in the flue gas that may wear out the catalyst and clog the catalyst, thereby posing a risk to the safe operation of the denitrification device. At the same time, based on the uniform flow of the flue gas, the denitrification effect of the subsequent flue gas can also be improved.
[0052] Example 4 Refer to Example 3, except that the horizontal arrangement interval of the plurality of wind wheel ammonia mixers 9 is equal to the horizontal length n of the vertical flue 8. ; The vertical distance between the ammonia injection grid 10 and the multiple wind wheel ammonia mixers 9 is 400 mm; the wind wheel ammonia mixer 9 includes a wind wheel blade 91, a wind sleeve 92 and a wind wheel shaft 93, a plurality of the wind wheel blades 91 are installed on the wind sleeve 92 at preset intervals, the wind sleeve 92 is rotatably mounted on the wind wheel shaft 93, one end of the wind wheel shaft 93 is vertically connected to the side of the vertical flue 8; two adjacent wind wheel blades 91 are arranged in a cross-staggered manner.
[0053] It has been tested that the wide-load dust removal and denitrification system described in the present invention can further effectively improve the uniformity of the mixing of low-ash flue gas and ammonia compared to the solution in Example 3, thereby avoiding excessive ammonia escape and improving the denitrification efficiency of subsequent flue gas.
[0054] Example 5 Refer to Example 4 for implementation, except that the ammonia injection grid 10 includes an ammonia supply main pipe 101 and an ammonia injection branch pipe 102, the ammonia supply main pipe 101 is arranged outside the vertical flue 8, one end of a plurality of ammonia injection branch pipes 102 is connected to the ammonia supply main pipe 101, and the other end extends to the interior of the vertical flue 8, and a plurality of injection holes are opened on the ammonia injection branch pipes 102.
[0055] It has been tested that the wide-load dust removal and denitrification system described in the present invention can further effectively improve the uniformity of the mixing of low-ash flue gas and ammonia compared to the solution in Example 4, thereby avoiding excessive ammonia escape and improving the denitrification efficiency of subsequent flue gas.
[0056] Example 6 Refer to Example 5 for implementation, except that the flue gas deflector 13 includes a plurality of flue gas deflector wings 131 arranged at intervals, the flue gas deflector 131 includes a deflector wing 1311 and a beak 1312 connected to one end of the deflector wing 1311, the deflector wing 1311 is an obtuse-angled deflector wing, the beak 1312 is a right-angled beak, and the long side of the right-angled beak is connected to one end of the obtuse-angled deflector wing close to the denitrification reactor 15.
[0057] It has been tested that the wide-load dust removal and denitrification system described in the present invention can further effectively improve the diversion effect of the flue gas after uniform mixing, compared with the scheme in Example 5, so that the flue gas can react with the catalyst more evenly, thereby effectively improving the denitrification efficiency of the flue gas.
[0058] Example 7 Refer to Example 6 for implementation, except that a rectifying grid 16 is provided inside the denitration reactor 15 located above the catalyst layer 17, and a straight plate guide 14 is provided in the flue of the denitration reactor 15 located in front of the rectifying grid 16, and the straight plate guide 14 includes a plurality of straight plates inclined relative to the flue gas flow direction.
[0059] It has been tested that the wide-load dust removal and denitrification system described in the present invention can further effectively improve the rectification effect of the flue gas compared to the scheme in Example 6, so that the flue gas can react with the catalyst more evenly, thereby effectively improving the denitrification efficiency of the flue gas.
[0060] The wide-load dust removal and denitrification system provided by the present invention can guide the boiler flue gas into the horizontal flue by setting the boiler tail flue, and further by setting the flue wind speed balancing baffle in the horizontal flue. When the boiler is under high load, a large amount of flue gas can blow the flue wind speed balancing baffle into a horizontal state. When the load is reduced, the flue wind speed balancing baffle will gradually return to a vertical state as the airflow decreases, forcing the flue gas to flow mainly through the bottom of the horizontal flue smoke inlet, ensuring that the flue gas at the bottom of the horizontal flue smoke inlet is always flowing at a high flow rate, which can fully carry the smoke dust and avoid the smoke dust from accumulating on the bottom surface of the horizontal flue smoke inlet, resulting in smoke dust blockage and increased power consumption of the unit operation; and further by setting a strip grille at the connection between the vertical flue and the horizontal flue A deflector is provided, and a baffle dust collector and an ash storage bin are arranged below the strip grid deflector. When the flue gas carrying dust reaches the baffle dust collector area, the smoke dust can fall into the ash storage bin under the inertia and the obstruction of the baffle dust collector and the strip grid deflector, and the low-ash flue gas goes up after the uniform flow through the strip grid deflector, thereby effectively avoiding the high dust content in the flue gas from wearing the catalyst and clogging the catalyst, which brings risks to the safe operation of the denitrification device; and further, by arranging an ammonia spray grid and multiple wind wheel ammonia mixers, a vortex street of air flow can be formed based on turbulence to achieve uniform mixing of ammonia and low-ash flue gas, thereby avoiding excessive ammonia escape; and further, by arranging a flue gas deflector, the flue gas can react with the catalyst more evenly, thereby effectively improving the denitrification efficiency of the flue gas.
[0061] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations. However, these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.
Claims
1. A wide load dust removal and denitrification system, characterized in that: The wide-load dust removal and denitrification system comprises a boiler tail flue (1), a T-shaped flue and a denitrification reactor (15); The T-shaped flue comprises a horizontal flue (3) and a vertical flue (8) vertically connected to the horizontal flue (3); the smoke inlet of the horizontal flue (3) is connected to the smoke outlet of the boiler tail flue (1); one or more flue wind speed balancing baffles (2) are arranged inside the horizontal flue (3); the smoke outlet of the vertical flue (8) is connected to the smoke inlet of the denitration reactor (15), and a smoke deflector (13) is arranged at the connection point; the connection between the vertical flue (8) and the horizontal flue (3) is as follows: A strip grid flow guide (7) is arranged at the opening of the horizontal flue (3), one or more baffle dust collectors (6) are arranged inside the horizontal flue (3) located below the baffle dust collector (6), the horizontal flue (3) is connected to an ash storage bin (5) below the baffle dust collector (6), the vertical flue (8) is arranged above the strip grid flow guide (7), an ammonia injection grid (10) and a plurality of wind wheel ammonia mixers (9) are arranged inside the vertical flue (8), and at least one catalyst layer (17) is arranged inside the denitration reactor (15).
2. The wide-load dust removal and denitrification system according to claim 1 is characterized in that: A plurality of flue wind speed balancing baffles (2) are arranged at preset intervals in the horizontal direction and the vertical direction inside the horizontal flue (3).
3. The wide-load dust removal and denitrification system according to claim 2 is characterized in that: The total height b of the plurality of flue wind speed balancing baffles (2) arranged at intervals in the vertical direction is equal to the vertical height m inside the horizontal flue (3). .
4. The wide-load dust removal and denitrification system according to any one of claims 1 to 3, characterized in that: The flue wind speed balancing baffle (2) comprises an upper wind baffle (21), a sleeve (22), a core shaft (23) and a lower wind baffle (24); the upper wind baffle (21) and the lower wind baffle (24) are mounted on the sleeve (22) in opposite directions; the sleeve (22) is rotatably mounted on the core shaft (23); one end of the core shaft (23) is vertically connected to a side surface of the horizontal flue (3).
5. The wide-load dust removal and denitrification system according to claim 4, characterized in that: The height of the lower wind shield (24) is greater than the height of the upper wind shield (21); and a plurality of ash discharge holes are provided on the surface of the sleeve (22).
6. The wide-load dust removal and denitrification system according to claim 1, characterized in that: The baffle dust collector (6) comprises a plurality of right-angle baffle dust removal plates (61), and the plurality of right-angle baffle dust removal plates (61) are arranged in a stepped manner at a preset angle inside the horizontal flue (3).
7. The wide-load dust removal and denitrification system according to claim 6, characterized in that: The preset angle is a=arctan(m / n), wherein m is the vertical height inside the horizontal flue, and n is the horizontal length inside the vertical flue.
8. The wide-load dust removal and denitrification system according to claim 1 or 6, characterized in that: The spacing c between two adjacent baffle dust collectors (6) is equal to the horizontal length n inside the vertical flue. .
9. The wide-load dust removal and denitrification system according to claim 1, characterized in that: The strip grid guide (7) comprises a plurality of strip plates (71) arranged at preset intervals, wherein the preset intervals are equal to a height d of the strip plates (71). The plate surfaces of the plurality of strip plates (71) are arranged parallel to the flow direction of the smoke.
10. The wide-load dust removal and denitrification system according to claim 1, characterized in that: The horizontal arrangement interval of the plurality of wind wheel ammonia mixers (9) is equal to the horizontal length n of the interior of the vertical flue (8). The vertical distance between the ammonia injection grid (10) and the plurality of wind wheel ammonia mixers (9) is 300 mm to 500 mm.
11. The wide-load dust removal and denitrification system according to claim 1 or 10, characterized in that: The wind wheel ammonia mixer (9) comprises a wind wheel blade (91), a wind sleeve (92) and a wind wheel shaft (93), wherein a plurality of the wind wheel blades (91) are mounted on the wind sleeve (92) at preset intervals, the wind sleeve (92) is rotatably mounted on the wind wheel shaft (93), and one end of the wind wheel shaft (93) is vertically connected to a side surface of the vertical flue (8).
12. The wide-load dust removal and denitrification system according to claim 11, characterized in that: Two adjacent wind wheel blades (91) are arranged in a cross-staggered manner; and a plurality of ash outlet holes are provided on the surface of the wind sleeve (92).
13. The wide-load dust removal and denitrification system according to claim 1, characterized in that: The ammonia injection grid (10) comprises an ammonia supply main pipe (101) and an ammonia injection branch pipe (102); the ammonia supply main pipe (101) is arranged outside the vertical flue (8); one end of a plurality of ammonia injection branch pipes (102) is connected to the ammonia supply main pipe (101), and the other end extends to the inside of the vertical flue (8); and a plurality of injection holes are provided on the ammonia injection branch pipes (102).
14. The wide-load dust removal and denitrification system according to claim 1, characterized in that: The smoke deflector (13) comprises a plurality of smoke deflector wings (131) arranged at intervals, and the smoke deflector wing (131) comprises a deflector wing (1311) and a beak (1312) connected to one end of the deflector wing (1311).
15. The wide-load dust removal and denitrification system according to claim 14, characterized in that: The guide fin (1311) is an obtuse-angled guide fin, and the beak (1312) is a right-angled beak, wherein the long side of the right-angled beak is connected to one end of the obtuse-angled guide fin close to the denitration reactor (15).
16. The wide-load dust removal and denitrification system according to claim 1 or 14, characterized in that: A rectifying grid (16) is provided inside the denitration reactor (15) located above the catalyst layer (17).
17. The wide-load dust removal and denitrification system according to claim 16, characterized in that: The denitration reactor (15) is provided with a straight plate flow guide (14) in the flue at the front end of the rectifying grid (16), wherein the straight plate flow guide (14) comprises a plurality of straight plates arranged obliquely relative to the direction of flue gas flow.
18. The wide-load dust removal and denitrification system according to claim 1, characterized in that: The boiler tail flue (1) comprises a straight flue (11) and an inclined flue (12) connected to the straight flue (11), and a smoke outlet of the inclined flue (12) is connected to a smoke inlet of the horizontal flue (3).