Multi-section type long-service-life energy-saving efficient multi-nozzle spray gun

Abstract

The invention belongs to the technical field of flue gas denitration, and discloses a multi-section long-service-life energy-saving efficient multi-nozzle spray gun which comprises a plurality of gun bodies spliced end to end, first reducing agent inner pipes communicated with one another are arranged in the gun bodies, second reducing agent inner pipes are arranged in the gun body located at the head end, and first reducing agent inner pipes are arranged in the gun body located at the tail end; the gun body at the head end is provided with a first nozzle communicated with the second reducing agent inner pipe, and the gun bodies at the middle part and the tail part are provided with second nozzles communicated with the first reducing agent inner pipe; the first mixer is connected to the head end of the first reducing agent inner pipe, and a first reducing agent inlet and a first atomized gas inlet are formed in the first mixer; the second mixer is connected to the head end of the second reducing agent inner pipe, and a second reducing agent inlet and a second atomized gas inlet are formed in the second mixer; an air inlet and an air outlet are formed in the gun body at the head end, the air inlet is connected with an air supply source, and the air outlet is communicated with the first atomized air inlet and the second atomized air inlet. The spray gun is good in flue gas denitration effect and long in service life.

Description

Technical Field

[0001] The invention relates to the technical field of flue gas denitration, and more particularly to a multi-stage, long-life, energy-saving and high-efficiency multi-nozzle spray gun. Background Art

[0002] SNCR denitrification is a denitrification technology commonly used in power plant boilers. SNCR stands for selective non-catalytic reduction. Selective non-catalytic reduction refers to the reduction of nitrogen oxides in flue gas to harmless nitrogen and water by injecting a reducing agent within the "temperature window" suitable for denitrification reaction without the action of a catalyst. This technology generally uses ammonia, urea or amino acid as a reducing agent to reduce NO X The reducing agent only reacts with NO in the flue gas. X Reaction, generally does not react with oxygen, this technology does not use a catalyst, so this method is called selective non-catalytic reduction. The denitrification spray gun is an important part of SNCR denitrification, and its main purpose is to spray the denitrification reducing agent into the temperature appropriate area through compressed air to achieve the purpose of denitrification. For example, the prior art publication number is CN115672004A, and the name is a fluidized bed boiler SNCR ultra-low emission denitrification device.

[0003] However, for the denitrification of large boilers, the existing denitrification spray guns have low denitrification spray coverage efficiency due to length limitations, which in turn affects the flue gas denitrification efficiency. In addition, because the existing spray guns use multiple nozzles, when the compressed air source is insufficient, the spray capacity of the nozzles is reduced, and the sprayed reducing agent cannot reach the flue gas far away from the nozzles, thereby reducing the flue gas denitrification efficiency. Moreover, the reducing agent sprayed through the nozzles may not be atomized to a high degree due to insufficient compressed air, and thus cannot be fully mixed with the flue gas, thereby reducing the flue gas denitrification efficiency.

[0004] Therefore, how to provide a multi-stage, long-life, energy-saving and efficient multi-nozzle spray gun that has good flue gas denitrification effect and can meet the high-efficiency requirements of large-scale boiler denitrification injection coverage is an urgent problem that technical personnel in this field need to solve. Summary of the invention

[0005] In view of this, the present invention provides a multi-stage, long-life, energy-saving and efficient multi-nozzle spray gun which has good flue gas denitrification effect and can meet the high-efficiency requirements of large boiler denitrification spray coverage.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A multi-stage long-life energy-saving and high-efficiency multi-nozzle spray gun, comprising:

[0008] A gun body, wherein the gun body is a plurality of gun bodies connected end to end, each of the gun bodies is provided with a first reducing agent inner tube connected to each other, the gun body at the head end is provided with a second reducing agent inner tube, and the gun body at the head end is provided with a plurality of first nozzles connected to the second reducing agent inner tube, and the gun bodies at the middle and tail parts are provided with a plurality of second nozzles connected to the first reducing agent inner tube;

[0009] a first mixer, the first mixer being connected to the head end of the first reducing agent inner tube, and the first mixer being provided with a first reducing agent inlet and a first atomized gas inlet;

[0010] a second mixer, the second mixer being connected to the head end of the second reducing agent inner tube, and the second reducing agent inlet and the second atomized gas inlet being provided on the second mixer;

[0011] Wherein, an air inlet and an air outlet are provided on the gun body at the head end, the air inlet is connected to an air supply source, and the air outlet is connected to both the first atomizing gas inlet and the second atomizing gas inlet.

[0012] Through the above technical scheme, it can be known that compared with the prior art, the present invention discloses a multi-stage long-life energy-saving and high-efficiency multi-nozzle spray gun, which is made of a multi-stage gun body spliced ​​together, which can not only increase the length of the spray gun so that it can meet the use requirements of large boiler denitrification, but also, the spray gun adopts a multi-stage spliced ​​gun body, which is easy to manufacture, has strong bending resistance and long service life compared to directly processing a gun body of the same length; in addition, the spray gun first allows compressed air to enter the interior of the gun body through the air inlet, which not only plays a role in cooling the gun body, but also the high-temperature gas after heating enters the first mixing gas through the air outlet, the first atomizing gas inlet and the second atomizing gas inlet respectively. The first mixer and the second mixer are used to respectively perform high-temperature atomization on the liquid first reducing agent and the liquid second reducing agent entering the first mixer and the second mixer, thereby improving the atomization effect of the first reducing agent and the second reducing agent, so that the fully atomized first reducing agent and the second reducing agent are respectively sprayed out in the form of atomization through the second nozzle and the first nozzle, thereby improving the full contact between the reducing agent and the flue gas and improving the efficiency and effect of flue gas denitrification. Moreover, the second mixer, the second reducing agent inner tube and the first nozzle are used to realize the injection of the reducing agent of the head end gun body, and the first mixer, the first reducing agent inner tube and the second nozzle are used to realize the injection of the reducing agent of the middle and tail gun body, thereby ensuring the injection capacity of the overall spray gun.

[0013] Therefore, the spray gun of the present invention firstly adopts a multi-section gun body to be spliced ​​into a longer spray gun, which can meet the use requirements of large boiler denitration; secondly, the double mixer is used to atomize the reducing agent at high temperature, which not only ensures the spraying capacity of the overall longer spray gun, but also improves the atomization effect of the liquid reducing agent, thereby improving the full contact between the reducing agent and the flue gas, and ensuring the flue gas denitration effect. In addition, the compressed air is first used as cooling air and then as atomizing air, which reduces the use of compressed air and achieves energy saving; at the same time, the heat of the cooling process is used to heat the compressed air for atomization to achieve high-temperature atomization of the liquid reducing agent, thereby achieving energy saving.

[0014] Furthermore, each of the gun bodies is provided with a partition, and two adjacent partitions are spliced ​​end to end, and the partition divides the interior of the gun body into a lower air inlet chamber and an upper air outlet chamber. There is a gap between one side of the partition located at the rear and the rear end of the gun body, and the lower air inlet chamber and the upper air outlet chamber are connected through the gap, the air inlet is connected to the lower air inlet chamber, and the air outlet is connected to the upper air outlet chamber.

[0015] The beneficial effect of adopting the above technical solution is that the lower air inlet cavity and the upper air outlet cavity can form a U-shaped cavity, so that the cooling air entering through the air inlet passes through a U-shaped loop and comes out from the air outlet, so that the cooling air can flow through the entire spray gun, thereby achieving cooling of the entire spray gun.

[0016] Furthermore, the first atomizing gas inlet is connected to the air outlet through a first loop pipe, the second atomizing gas inlet is connected to the first loop pipe through a second loop pipe, the air supply source is connected to a main air pipe, the main air pipe is connected to a first compressed air branch pipe and a second compressed air branch pipe, the first compressed air branch pipe is connected to the air inlet, and the second compressed air branch pipe is connected to the first loop pipe.

[0017] The beneficial effects produced by the above technical solution are: the gas from the air supply source enters the gun body through the first compressed air branch pipe via the air inlet to cool the gun body, and then the high-temperature gas after heat exchange heating in the gun body enters the first mixer and the second mixer through the air outlet through the first loop pipe and the second loop pipe respectively to atomize the reducing agent at high temperature. In addition, in order to increase the air supply pressure in the middle and tail parts of the spray gun, part of the gas from the air supply source enters the first mixer together with the high-temperature gas through the second compressed air branch pipe.

[0018] Furthermore, a compressed air switch valve is provided on the second compressed air branch pipe.

[0019] The beneficial effect of adopting the above technical solution is that the on-off of the second compressed air branch pipe can be controlled by the compressed air switch valve according to actual use requirements.

[0020] Furthermore, the first compressed air branch pipe is provided with an inlet air volume regulating valve.

[0021] The beneficial effect of adopting the above technical solution is that the air volume at the air inlet can be adjusted by the inlet air volume regulating valve according to usage requirements.

[0022] Furthermore, a first atomizing air volume regulating valve is provided on the second loop pipe, and a second atomizing air volume regulating valve is provided on the first loop pipe at a position close to the first atomizing gas inlet.

[0023] The beneficial effect of adopting the above technical solution is that the size of the high-temperature atomizing air entering the first mixer and the second mixer can be adjusted respectively according to the use requirements.

[0024] Furthermore, a return atomization air valve is provided on the first loop pipe near the air outlet, and an exhaust pipe is also connected to the first loop pipe, and an exhaust valve is provided on the exhaust pipe.

[0025] The beneficial effect of adopting the above technical solution is: when high-temperature return air is required, the exhaust valve is closed and the return atomization air valve is opened; when exhaust is required, the return atomization air valve is closed and the exhaust valve is opened, so that the gas in the gun body can be quickly discharged.

[0026] Furthermore, reinforcing ribs are provided on the outer wall between two adjacent gun bodies.

[0027] The beneficial effects of adopting the above technical solution are: improving the bending resistance of the connection position of the gun body and increasing the service life of the spray gun.

[0028] Furthermore, the outer gun wall of each gun body is coated with an adhesive layer, a heat insulation layer and a wear-resistant layer in sequence.

[0029] The beneficial effects of adopting the above technical scheme are: the bonding layer can increase the bonding force between the gun body and the thermal insulation layer, the thermal insulation layer reduces the heat transfer from the outside of the spray gun to the inside of the spray gun, and can improve the heat resistance of the spray gun to adapt it to the use of high-temperature flue gas. The wear-resistant layer can increase the service life of the spray gun in high-speed, high-temperature, dusty harsh use environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0031] Figure 1 A schematic structural diagram of a multi-stage, long-life, energy-saving and high-efficiency multi-nozzle spray gun provided by the present invention.

[0032] Figure 2 This is an enlarged schematic diagram of the gun body structure located at the head.

[0033] Figure 3 This is an enlarged schematic diagram of the gun body structure located in the middle and tail parts. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] like Figure 1-Figure 3 As shown, the embodiment of the present invention discloses a multi-stage long-life energy-saving and high-efficiency multi-nozzle spray gun, which penetrates the flue gas cross section and can ensure that all flue gas and denitrification agent (reducing agent) on the flue cross section are easily and fully mixed. Specifically, the spray gun includes:

[0036] A gun body 1, wherein the gun bodies 1 are connected end to end and are multiple, for example, the multiple gun bodies 1 can be welded, flanged, or bonded, etc., each gun body 1 is provided with a first reducing agent inner tube 2 that is connected to each other, the gun body 1 located at the head end is provided with a second reducing agent inner tube 3, and the gun body 1 located at the head end is provided with a plurality of first nozzles 4 that are connected to the second reducing agent inner tube 3, and the gun bodies 1 located in the middle and tail are provided with a plurality of second nozzles 5 that are connected to the first reducing agent inner tube 2;

[0037] The first nozzle 4 and the second nozzle 5 are both in various forms such as fan-shaped nozzles, single-hole cone nozzles, multi-hole cone nozzles, etc. The nozzle material is stainless steel or Hastelloy and other materials, and the nozzle angle range is 30°~150°;

[0038] A first mixer 6, the first mixer 6 is connected to the head end of the first reducing agent inner tube 2, and is provided with a first reducing agent inlet 7 (with a pressure of 0.3-0.8 MPa, from a denitrifying agent supply system) and a first atomizing gas inlet 8;

[0039] A second mixer 9, the second mixer 9 is connected to the head end of the second reducing agent inner tube 3, and is provided with a second reducing agent inlet 10 (with a pressure of 0.3-0.8 MPa, from a denitrification agent supply system) and a second atomized gas inlet 11;

[0040] Among them, an air inlet 12 and an air outlet 13 are provided on the gun body 1 located at the head end. The air inlet 12 is connected to the air supply source (compressed air is 0.3~0.7MPa, from the air pump of the factory, etc.), and the air outlet 13 is connected to the first atomizing gas inlet 8 and the second atomizing gas inlet 11.

[0041] Each gun body 1 is provided with a partition 14 inside, and two adjacent partitions 14 are spliced ​​end to end. The partition 14 divides the interior of the gun body 1 into a lower air inlet chamber 15 and an upper air outlet chamber 16. There is a gap 30 between one side of the partition 14 located at the rear and the rear end of the gun body 1. The lower air inlet chamber 15 and the upper air outlet chamber 16 are connected through the gap 30, the air inlet 12 is connected to the lower air inlet chamber 15, and the air outlet 13 is connected to the upper air outlet chamber 16.

[0042] The first atomizing gas inlet 8 is connected to the air outlet 13 through the first loop pipe 17, the second atomizing gas inlet 11 is connected to the first loop pipe 17 through the second loop pipe 18, the air supply source is connected to the main air pipe 19, the main air pipe 19 is connected to the first compressed air branch pipe 20 and the second compressed air branch pipe 21, the first compressed air branch pipe 20 is connected to the air inlet 12, and the second compressed air branch pipe 21 is connected to the first loop pipe 17.

[0043] The second compressed air branch pipe 21 is provided with a compressed air switch valve 22 .

[0044] The first compressed air branch pipe 20 is provided with an inlet air volume regulating valve 23 .

[0045] A first atomizing air volume regulating valve 24 is provided on the second loop pipe 18 , and a second atomizing air volume regulating valve 25 is provided on the first loop pipe 17 near the first atomizing gas inlet 8 .

[0046] A return atomizing air valve 26 is provided on the first loop pipe 17 near the air outlet 13 . An exhaust pipe 27 is also connected to the first loop pipe 17 , and an exhaust valve 28 is provided on the exhaust pipe 27 .

[0047] A reinforcing rib 29 is provided on the outer wall between two adjacent gun bodies 1 .

[0048] The outer gun wall of each gun body 1 is covered with an adhesive layer, a heat insulation layer and a wear-resistant layer in sequence.

[0049] The compressed air of the present invention first enters the spray gun and then enters the mixer, which not only cools the spray gun, but also makes full use of the gas to become high-temperature gas after being heated by the spray gun, so as to realize the atomization of the liquid reducing agent using the high-temperature gas, and has obvious energy-saving and emission-reduction effects. Moreover, the multi-stage design of the gun body saves materials and greatly improves the bending resistance of the longer spray gun, solving the problem of low spray coverage efficiency of SNCR denitration of large boilers. In addition, the double-mixer high-temperature atomization design solves the problem of insufficient gas source and poor penetration of the multi-hole spray gun.

[0050] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0051] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A multi-stage long-life energy-saving and high-efficiency multi-nozzle spray gun, characterized in that: include: A gun body (1), the gun body (1) being a plurality of gun bodies connected end to end and connected, each gun body (1) being provided with a first reducing agent inner tube (2) connected to each other, the gun body (1) located at the head end being provided with a second reducing agent inner tube (3), and the gun body (1) located at the head end being provided with a plurality of first nozzles (4) connected to the second reducing agent inner tube (3), and the gun bodies (1) located at the middle and tail portions being provided with a plurality of second nozzles (5) connected to the first reducing agent inner tube (2); a first mixer (6), the first mixer (6) being connected to the head end of the first reducing agent inner tube (2), the first mixer (6) being provided with a first reducing agent inlet (7) and a first atomized gas inlet (8); a second mixer (9), the second mixer (9) being connected to the head end of the second reducing agent inner tube (3), and the second reducing agent inlet (10) and the second atomized gas inlet (11) being provided on the second mixer (9); The gun body (1) at the head end is provided with an air inlet (12) and an air outlet (13), the air inlet (12) is connected to an air supply source, and the air outlet (13) is connected to both the first atomizing gas inlet (8) and the second atomizing gas inlet (11).

2. A multi-stage, long-life, energy-saving and high-efficiency multi-nozzle spray gun according to claim 1, characterized in that: Each gun body (1) is provided with a partition (14) inside, and two adjacent partitions (14) are spliced ​​end to end, and the partition (14) divides the inside of the gun body (1) into a lower air inlet chamber (15) and an upper air outlet chamber (16). A gap (30) is provided between one side of the partition (14) located at the rear and the rear end of the gun body (1), and the lower air inlet chamber (15) and the upper air outlet chamber (16) are connected through the gap (30), the air inlet (12) is connected to the lower air inlet chamber (15), and the air outlet (13) is connected to the upper air outlet chamber (16).

3. A multi-stage long-life energy-saving and high-efficiency multi-nozzle spray gun according to claim 1 or 2, characterized in that: The first atomizing gas inlet (8) is connected to the air outlet (13) via a first loop pipe (17); the second atomizing gas inlet (11) is connected to the first loop pipe (17) via a second loop pipe (18); the air supply source is connected to a main air pipe (19); the main air pipe (19) is connected to a first compressed air branch pipe (20) and a second compressed air branch pipe (21); the first compressed air branch pipe (20) is connected to the air inlet (12); and the second compressed air branch pipe (21) is connected to the first loop pipe (17).

4. A multi-stage long-life energy-saving and high-efficiency multi-nozzle spray gun according to claim 3, characterized in that: The second compressed air branch pipe (21) is provided with a compressed air switch valve (22).

5. The multi-stage long-life energy-saving and high-efficiency multi-nozzle spray gun according to claim 3, characterized in that: The first compressed air branch pipe (20) is provided with an inlet air volume regulating valve (23).

6. The multi-stage long-life energy-saving and high-efficiency multi-nozzle spray gun according to claim 3, characterized in that: A first atomizing air volume regulating valve (24) is provided on the second loop pipe (18), and a second atomizing air volume regulating valve (25) is provided on the first loop pipe (17) at a position close to the first atomizing air inlet (8).

7. The multi-stage long-life energy-saving and high-efficiency multi-nozzle spray gun according to claim 3, characterized in that: A return atomization air valve (26) is provided on the first loop pipe (17) at a position close to the air outlet (13); an exhaust pipe (27) is also connected to the first loop pipe (17); and an exhaust valve (28) is provided on the exhaust pipe (27).

8. A multi-stage, long-life, energy-saving and high-efficiency multi-nozzle spray gun according to any one of claims 1, 2, 4-6, characterized in that: A reinforcing rib (29) is provided on the outer wall between two adjacent gun bodies (1).

9. A multi-stage, long-life, energy-saving and high-efficiency multi-nozzle spray gun according to any one of claims 1, 2, 4-6, characterized in that: The outer gun wall of each gun body (1) is sequentially coated with an adhesive layer, a heat insulation layer, and a wear-resistant layer.

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