Ammonia spraying device for sintering flue gas activated carbon purification process

Abstract

The utility model provides an ammonia spraying device for an activated carbon purification process of sintering flue gas. The ammonia spraying device comprises a flue, and a rectifying part and an ammonia water atomizing spraying device which are arranged in the flue and are sequentially arranged along the flowing direction of the flue gas, the ammonia water atomizing and spraying device comprises a plurality of spray guns, the spray guns are connected with an ammonia water conveying branch and a compressed air conveying branch, a plurality of nozzles used for spraying atomized ammonia water are arranged on the spray guns, and the spraying direction of the nozzles is the same as the flowing direction of flue gas. According to the utility model, the ammonia water is heated and evaporated by utilizing the heat of the original flue gas, an additional heat source is not needed, the operation cost is reduced, and compared with a steam type ammonia water vaporization process, the steam consumption and the power consumption are reduced, and meanwhile, the flue gas flow resistance is also reduced; the intermediate link of ammonia water vaporization is reduced, and higher response speed and adjustment precision can be obtained.

Description

Technical Field

[0001] The utility model relates to the technical field of activated carbon purification technology for sintering flue gas, and in particular to an ammonia spraying device for the activated carbon purification technology for sintering flue gas. Background Art

[0002] Sintering is one of the important production process links in steel production enterprises. It not only consumes a lot of energy but also produces a lot of dust and harmful gases. The activated carbon flue gas purification process can remove SO2 and NO at the same time. x , dioxins, heavy metals, dust and other pollutants and can recycle sulfur resources. It is a resource recovery type flue gas comprehensive treatment technology.

[0003] The two-stage activated carbon flue gas purification process has gradually become the main process route for sintering flue gas treatment. The two-stage activated carbon flue gas purification process uses ammonia water with a concentration of 20% as a denitrification reducing agent. The commonly used ammonia injection process is to pressurize the ammonia water through an ammonia water delivery pump and enter the ammonia water evaporator. The ammonia water is vaporized into ammonia steam by steam. The ammonia steam is mixed with the 120°C dilution air delivered by the dilution fan and then sprayed into the flue. The diluted ammonia steam is mixed with the flue gas through the ammonia injection grid and enters the adsorption tower with the flue gas for denitrification reaction. However, this method has some shortcomings: 1) The dilution fan is generally not available for backup. Once a failure occurs, ammonia denitrification cannot be performed by spraying, resulting in The outlet nitrogen oxides exceeded the standard and the sintering was forced to shut down; 2) The ammonia evaporator is a special equipment and the equipment leak cannot be repaired by welding. Once it leaks, it will cause serious steam leakage on site and affect the denitrification effect; 3) The steam network supply is delayed during startup, and the steam pressure is less than 0.2MPa, which leads to the inability to completely evaporate the ammonia water, and ammonia vapor condenses and accumulates in the ammonia pipeline; 4) When the temperature of the ammonia and air mixture is lower than 100℃, the flue gas entering the end of the grille will form local condensation and cause grille corrosion; 5) The ammonia flow passes through the ammonia regulating valve and then evaporates through the ammonia evaporator to the ammonia-air mixer. The ammonia evaporation process is long and the flow regulation is delayed.

[0004] In summary, there is an urgent need for an ammonia injection device for sintering flue gas activated carbon purification process to solve the problems existing in the prior art. Utility Model Content

[0005] The utility model aims to provide an ammonia injection device for sintering flue gas activated carbon purification process, aiming to solve the shortcomings of the existing ammonia injection method. The specific technical scheme is as follows:

[0006] An ammonia spraying device for a sintering flue gas activated carbon purification process comprises a flue and a rectifying component and an ammonia water atomizing spraying device which are arranged inside the flue and in sequence along the flue gas flow direction; the ammonia water atomizing spraying device comprises a plurality of spray guns which are connected to an ammonia water delivery branch and a compressed air delivery branch, the spray guns are provided with a plurality of nozzles for spraying atomized ammonia water, and the spraying direction of the nozzles is in the same direction as the flue gas flow direction.

[0007] Preferably in the above technical solution, the length direction of the spray gun is perpendicular to the flow direction of the smoke, and the spray gun is evenly provided with a plurality of nozzles along its length direction, and the injection velocity of the nozzles is more than 4 times the flow velocity of the smoke.

[0008] Preferably, in the above technical solution, the plurality of spray guns are evenly distributed on the same flow cross section of the flue, and the nozzles are evenly arranged on the flow cross section.

[0009] Preferably in the above technical solution, a spray gun mounting sleeve connected to the interior thereof and a spray gun support beam arranged inside the flue are provided on the peripheral side wall of the flue; a connecting flange is provided on the spray gun, the spray gun is inserted into the interior of the flue through the spray gun mounting sleeve and is supported by the spray gun support beam, and the connecting flange is used to be fixedly connected to the spray gun mounting sleeve.

[0010] Preferably in the above technical solution, the spray gun is provided with an ammonia inlet and a compressed air inlet, the ammonia inlet and the compressed air inlet are located on a side of the connecting flange away from the flue, and the nozzle is located on a side of the connecting flange close to the flue.

[0011] Preferably in the above technical solution, the delivery pressure in the ammonia delivery branch is 0.2-0.3Mpa, and the delivery pressure in the compressed air delivery branch is 0.3-0.4Mpa.

[0012] Preferably in the above technical solution, the opening and closing of the ammonia water delivery branch and the compressed air delivery branch are controlled according to the flue gas temperature at the flue inlet.

[0013] Preferably in the above technical solution, the rectifying component includes N rectifying grids arranged in sequence along the flue gas flow direction, wherein N is a natural number greater than or equal to 1; the rectifying grid is a grid structure composed of a plurality of rectifying plates arranged horizontally and a plurality of rectifying plates arranged vertically.

[0014] Preferably, in the above technical solution, when N is a natural number greater than or equal to 2, the rectifier plates of two adjacent rectifier grids are staggered.

[0015] Preferably, in the above technical solution, the rectifying plate is a V-shaped structure composed of two guide plates, and the angle α between the two guide plates is 40°-60°.

[0016] The application of the technical solution of the utility model has the following beneficial effects:

[0017] The ammonia spraying device in the utility model first distributes the flue gas evenly through the rectifying component, and then sprays out ultra-fine ammonia droplets through the ammonia atomizing spraying device. The ultra-fine ammonia droplets are rapidly vaporized into ammonia vapor under the action of the hot flue gas and are evenly mixed with the flue gas. The heat of the original flue gas is used to heat and evaporate the ammonia, and no additional heat source is required, thereby reducing the operating cost. Compared with the steam-type ammonia vaporization process, the steam consumption and power consumption are reduced, and the flow resistance of the flue gas is also reduced. By reducing the intermediate links of ammonia vaporization, faster response speed and adjustment accuracy can be obtained.

[0018] The ammonia injection device of the utility model can meet the requirements of flue gas load under all working conditions, the main equipment is simple, no special equipment is required, the equipment cost is greatly reduced, the installation and maintenance are convenient, and online maintenance can be realized.

[0019] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0021] Figure 1 This is a working principle diagram of ammonia atomization in the ammonia spraying device of the utility model;

[0022] Figure 2 It is a structural schematic diagram of the ammonia injection device of the utility model;

[0023] Figure 3 yes Figure 2 Sectional view at AA in the middle;

[0024] Figure 4 yes Figure 2 A cross-sectional view of the middle BB after the spray gun is hidden;

[0025] Figure 5 yes Figure 2 Sectional view at CC;

[0026] Figure 6 yes Figure 3 Sectional view at DD in the middle;

[0027] Figure 7 yes Figure 2 Schematic diagram of the structure of the spray gun;

[0028] Among them, 1. Ammonia delivery branch, 1.1. Ammonia storage tank, 1.2. Ammonia delivery pump, 2. Compressed air delivery branch, 2.1. Compressed air source, 3. Flue, 3.1. Spray gun installation sleeve, 3.2. Spray gun support beam, 4. Spray gun, 4.1. Ammonia inlet, 4.2. Compressed air inlet, 4.3. Connecting flange, 4.4. Nozzle, 5. Rectifier grid, 5.1. Rectifier plate. DETAILED DESCRIPTION

[0029] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively below, and preferred embodiments of the present invention are given. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0031] Example:

[0032] See also Figure 1-Figure 7 The present embodiment provides an ammonia spraying device for an activated carbon purification process of sintering flue gas, comprising a flue 3 and a rectifying component and an ammonia water atomizing spraying device arranged inside the flue 3 and arranged in sequence along the flue gas flow direction, that is, the flue gas is evenly distributed in the flue after passing through the rectifying component and then mixed with the ammonia water mist; the ammonia water atomizing spraying device comprises a plurality of spray guns 4, the spray guns 4 are connected to an ammonia water delivery branch 1 and a compressed air delivery branch 2, ammonia water is supplied to the spray guns 4 through the ammonia water delivery branch 1, and compressed air is supplied to the spray guns 4 through the compressed air delivery branch, and a plurality of nozzles 4.4 for spraying atomized ammonia water are provided on the spray guns 4, and the spraying direction of the nozzles 4.4 is in the same direction as the flue gas flow direction.

[0033] Specifically, the flue 3 in this embodiment is the flue at the outlet of the first-level adsorption tower in the sintering flue gas activated carbon purification process. The sintering flue gas enters the flue after desulfurization in the first-level adsorption tower. The sintering flue gas and ammonia are evenly mixed in the flue, and then a denitrification reaction occurs under the catalytic action of the activated carbon in the second-level adsorption tower.

[0034] See also Figure 2 and Figure 7The length direction of the spray gun 4 is perpendicular to the flow direction of the smoke. The spray gun 4 is evenly distributed with a plurality of nozzles 4.4 along its length direction. The spray direction of the nozzles 4.4 is in the same direction as the flow direction of the smoke. On the one hand, a good atomization effect can be ensured. On the other hand, since there is activated carbon dust in the smoke, the nozzle spray direction is along the flow direction of the smoke to reduce the risk of nozzle blockage.

[0035] Preferably, in order to improve the mixing degree of ammonia water mist and sintering flue gas, the injection flow rate of the nozzle 4.4 in this embodiment is set to be more than 4 times the flue gas flow rate. Specifically, the injection flow rate of the nozzle 4.4 in this embodiment is greater than 60m / s, ensuring that the injection flow rate of the ammonia water mist is much greater than the flue gas flow rate. The high speed difference between the two is used to improve the mixing degree of the atomized ammonia water and the flue gas, so that the ammonia water is evenly distributed in the flue gas.

[0036] like Figure 2 , Figure 4 and Figure 5 As shown, the plurality of spray guns 4 are evenly distributed on the same flow cross section of the flue 3, and the nozzles 4.4 are evenly arranged on the flow cross section; Figure 5 As shown, Figure 5 The circle in the figure represents the coverage of the ammonia water mist. By evenly distributing a plurality of nozzles 4.4 on the flow cross section of the flue, it is ensured that the flow cross section can be fully and evenly covered, thereby improving the mixing degree of the atomized ammonia water and the sintering flue gas.

[0037] Further, such as Figure 2 and Figure 4 As shown, the surrounding side wall of the flue 3 is provided with a spray gun installation sleeve 3.1 communicating with the interior thereof and a spray gun support beam 3.2 arranged inside the flue 3; the spray gun 4 is provided with a connecting flange 4.3, the spray gun 4 is inserted into the interior of the flue 3 through the spray gun installation sleeve 3.1 and supported by the spray gun support beam 3.2, and the connecting flange 4.3 is used to be fixedly connected to the spray gun installation sleeve 3.1. Among them, the spray gun support beam 3.2 is used to support the part of the spray gun located inside the flue to prevent the spray gun 4 from forming a cantilever beam after being installed through the spray gun installation sleeve 3.1, and the spray gun is deformed due to stress.

[0038] like Figure 7 As shown, in this embodiment, the spray gun 4 is provided with an ammonia inlet 4.1 and a compressed air inlet 4.2, and the nozzle 4.4 is connected with the ammonia inlet 4.1 and the compressed air inlet 4.2 respectively; the ammonia inlet 4.1 and the compressed air inlet 4.2 are located on the side of the connecting flange 4.3 away from the flue 3, and the nozzle 4.4 is located on the side of the connecting flange 4.3 close to the flue 3, that is, the ammonia inlet 4.1 and the compressed air inlet 4.2 are both located outside the flue, and each nozzle 4.4 is located inside the flue.

[0039] like Figure 5 As shown, the flow cross section of the flue in this embodiment is rectangular, and 12 spray guns 4 are arranged inside the flue, and three nozzles 4.4 are arranged on each spray gun 4, so that the effect of uniformly covering the entire flow cross section can be achieved. Among them, the structural arrangement of the nozzle to realize ammonia atomization can refer to the prior art.

[0040] like Figure 2 , Figure 3 and Figure 6 As shown, the rectifying component includes N rectifying grids 5 arranged in sequence along the flue gas flow direction, wherein N is a natural number greater than or equal to 1; the rectifying grid is a grid structure composed of a plurality of rectifying plates 5.1 arranged transversely and a plurality of rectifying plates 5.1 arranged longitudinally; further, the spacing between two adjacent rectifying plates in the transverse direction and the spacing between two rectifying plates in the longitudinal direction can be set by those skilled in the art according to the structural dimensions of the flue and the structure of the rectifying plate itself.

[0041] Preferably, when N is a natural number greater than or equal to 2, the rectifier plates of two adjacent rectifier grids 5 are staggered. Figure 6 As shown, in this embodiment, two rectifying grids are arranged inside the flue to rectify the flue gas twice so that the flue gas is evenly distributed in the flue gas.

[0042] See also Figure 6 , the rectifier plate 5.1 is a V-shaped structure composed of two guide plates, and the angle α between the two guide plates is 40°-60°. When the smoke contacts the rectifier plate 5.1, the smoke is divided into two streams by the rectifier plate with an inverted V-shaped cross-section, namely, two streams of smoke moving along the guide plate. The smoke moving along the guide plate has vertical and horizontal movement components, wherein the vertical movement component causes the smoke to continue to move downward, and the horizontal movement component causes the smoke to diffuse, thereby achieving the effect of uniform distribution of the smoke in the flue. The larger the value of the angle α, the more the horizontal movement component of the smoke will increase, and the more the vertical movement component will decrease, resulting in obstruction of the flow of the smoke and a reduction in the flow rate of the smoke; when the value of the angle α is smaller, the more the horizontal movement component of the smoke will decrease, and the more the vertical movement component will increase, thereby reducing the diffusion effect of the smoke; therefore, in this embodiment, the preferred angle α is 50°.

[0043] Preferably, the delivery pressure in the ammonia delivery branch 1 in this embodiment is 0.2-0.3Mpa, and the delivery pressure in the compressed air delivery branch 2 is 0.3-0.4Mpa. The delivery pressures of the ammonia delivery branch 1 and the compressed air delivery branch 2 will affect the atomization effect of ammonia; if the delivery pressure in the ammonia delivery branch 1 is too small, it will not be able to supply enough ammonia for atomization, and if the pressure is too high, the particles of the atomized ammonia will be larger, and the larger particles will not be convenient for mixing with the flue gas to form ammonia gas later; if the delivery pressure of the compressed air delivery branch 2 is too high, it will cause compressed air to enter the ammonia delivery branch and affect the ammonia supply. If the pressure is too low, the particles of the atomized ammonia will be larger. In this embodiment, the delivery pressure in the ammonia delivery branch 1 is 0.3Mpa, and the delivery pressure in the compressed air delivery branch 2 is 0.4Mpa.

[0044] Further, the structures of the ammonia water delivery branch 1 and the compressed air delivery branch 2 can be found in the prior art. In this embodiment, only a brief description of the two is given, as follows: Figure 1 The ammonia delivery branch 1 includes an ammonia storage tank 1.1 and an ammonia delivery pump 1.2, wherein the ammonia storage tank 1.1 is used to store ammonia, the outlet of the ammonia storage tank 1.1 is connected to the input end of the ammonia delivery pump 1.2 through a pipeline, and the output end of the ammonia delivery pump 1.2 is connected to the ammonia inlet 4.1 of the spray gun; the compressed air delivery branch 2 includes a compressed air source 2.1, and the compressed air source 2.1 is connected to the compressed air inlet 4.2 of the spray gun 4 through a pipeline. A pressure gauge and a flow meter are provided on the ammonia delivery branch 1 to achieve the effect of monitoring the pressure and flow in the ammonia delivery branch 1, and at the same time, it can effectively determine whether the spray gun is blocked or has other faults; by setting a flow transmitter, a flow indicating controller and a valve linkage control on the ammonia delivery branch, the effect of regulating the flow of ammonia can be achieved. Pressure gauges are provided on the main road and each branch road of the compressed air delivery branch 2 to monitor the compressed air supply pressure. Preferably, in order to prevent pipeline failure from causing failure to supply ammonia water and compressed air normally, additional spare branches can be set for the ammonia water delivery branch and the compressed air delivery branch. When the pipeline needs maintenance, it can be switched to the spare branch to prevent the sintering from being forced to shut down.

[0045] Preferably, the opening and closing of the ammonia delivery branch 1 and the compressed air delivery branch 2 in this embodiment are controlled according to the flue gas temperature at the entrance of the flue 3; when the flue gas temperature reaches the set value, the ammonia delivery branch 1 and the compressed air delivery branch 2 are linked to open; when the flue gas temperature is lower than the set value, the ammonia delivery branch 1 and the compressed air delivery branch 2 are linked to close. Specifically, a temperature detection device can be provided at the entrance of the flue, and the temperature detection device transmits the detected temperature value to the control unit, and the control unit controls the opening and closing of the valves of the ammonia delivery branch 1 and the compressed air delivery branch 2. In this embodiment, it is set that when the flue gas temperature is greater than 120°, the ammonia delivery branch and the compressed air delivery branch are opened, and when the flue gas temperature is lower than 120°, the ammonia delivery branch and the compressed air delivery branch are closed.

[0046] The ammonia spraying device in this embodiment first distributes the flue gas evenly in the flue through the rectifying component, and then sprays ultrafine ammonia droplets through the ammonia atomizing spraying device. The ultrafine ammonia droplets are quickly vaporized into ammonia vapor under the action of hot flue gas and are evenly mixed with the flue gas; the ammonia spraying device in this embodiment uses the heat of the original flue gas to heat and evaporate the ammonia, without the need for an additional heat source, which reduces the operating cost. Compared with the steam-type ammonia vaporization process, it reduces steam consumption and power consumption, and also reduces the flue gas flow resistance; reducing the intermediate link of ammonia vaporization can obtain faster response speed and regulation accuracy. The ammonia spraying device in this embodiment can meet the requirements of flue gas load under all working conditions. The main equipment is simple, without special equipment, the equipment cost is greatly reduced, and it is easy to install and maintain, and can realize online maintenance.

[0047] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. An ammonia injection device for sintering flue gas activated carbon purification process, characterized in that: The invention comprises a flue (3), and a rectifying component and an ammonia water atomizing spraying device which are arranged inside the flue (3) and in sequence along the flue gas flow direction; the ammonia water atomizing spraying device comprises a plurality of spray guns (4), the spray guns (4) are connected to an ammonia water delivery branch (1) and a compressed air delivery branch (2), the spray guns (4) are provided with a plurality of nozzles (4.4) for spraying atomized ammonia water, and the spraying direction of the nozzles (4.4) is in the same direction as the flue gas flow direction.

2. The ammonia injection device for the activated carbon purification process of sintering flue gas according to claim 1 is characterized in that: The length direction of the spray gun (4) is perpendicular to the flow direction of the smoke. The spray gun (4) is evenly distributed with a plurality of nozzles (4.4) along its length direction. The spray velocity of the nozzles (4.4) is more than 4 times the flow velocity of the smoke.

3. The ammonia injection device for the sintering flue gas activated carbon purification process according to claim 2 is characterized in that: The plurality of spray guns (4) are evenly distributed on the same flow cross section of the flue (3), and the nozzles (4.4) are evenly arranged on the flow cross section.

4. The ammonia injection device for the activated carbon purification process of sintering flue gas according to claim 1 is characterized in that: The flue (3) is provided with a spray gun mounting sleeve (3.1) connected to the interior thereof and a spray gun support beam (3.2) arranged inside the flue (3) on the peripheral side wall; the spray gun (4) is provided with a connecting flange (4.3); the spray gun (4) is inserted into the interior of the flue (3) through the spray gun mounting sleeve (3.1) and supported by the spray gun support beam (3.2); the connecting flange (4.3) is used for fixed connection with the spray gun mounting sleeve (3.1).

5. The ammonia injection device for the activated carbon purification process of sintering flue gas according to claim 4 is characterized in that: The spray gun (4) is provided with an ammonia water inlet (4.1) and a compressed air inlet (4.2), the ammonia water inlet (4.1) and the compressed air inlet (4.2) are located on a side of the connecting flange (4.3) away from the flue (3), and the nozzle (4.4) is located on a side of the connecting flange (4.3) close to the flue (3).

6. The ammonia injection device for the activated carbon purification process of sintering flue gas according to claim 1 is characterized in that: The delivery pressure in the ammonia delivery branch (1) is 0.2-0.3Mpa, and the delivery pressure in the compressed air delivery branch (2) is 0.3-0.4Mpa.

7. The ammonia injection device for the activated carbon purification process of sintering flue gas according to claim 1 is characterized in that: The opening and closing of the ammonia water delivery branch (1) and the compressed air delivery branch (2) are controlled according to the flue gas temperature at the entrance of the flue (3).

8. The ammonia injection device for the activated carbon purification process of sintering flue gas according to any one of claims 1 to 7, characterized in that: The rectifying component comprises N rectifying grids (5) arranged in sequence along the flue gas flow direction, wherein N is a natural number greater than or equal to 1; the rectifying grid is a grid structure composed of a plurality of rectifying plates (5.1) arranged transversely and a plurality of rectifying plates (5.1) arranged longitudinally.

9. The ammonia injection device for the activated carbon purification process of sintering flue gas according to claim 8 is characterized in that: When N is a natural number greater than or equal to 2, the rectifying plates of two adjacent rectifying grids (5) are arranged in a staggered manner.

10. The ammonia injection device for the activated carbon purification process of sintering flue gas according to claim 8, characterized in that: The rectifying plate (5.1) is a V-shaped structure composed of two guide plates, and the angle α between the two guide plates is 40°-60°.

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