Flue gas denitration device for thermal power unit

Abstract

This application discloses a flue gas denitrification device for thermal power units, specifically relating to the field of flue gas denitrification technology. It includes an upper shell, with at least two sets of rotary feed assemblies connected to the bottom of the upper shell. The bottom of the lowest rotary feed assembly is connected to a lower shell. An air outlet pipe extending from the top of the upper shell is coaxially embedded in the upper shell, and the bottom inlet of the air outlet pipe is lower than all the rotary feed assemblies. The upper shell and the air outlet pipe form an annular space within the upper shell cavity, and an air inlet pipe extending from the upper shell is tangent to the edge of this annular space. A waste liquid collection and discharge assembly is connected to the bottom of the lower shell. Each set of rotary feed assemblies includes an annular cylinder, with several uniformly distributed annular nozzles embedded in the annular cylinder. A feed ring is fitted over the annular cylinder, forming an annular cavity with the feed ring. A feed pipe extending from the feed ring is tangent to the edge of this annular cavity. This application can maintain the temperature of the pyrolysis reaction, allowing for the complete pyrolysis of NOx in the flue gas.

Description

Technical Field

[0001] This utility model belongs to the field of flue gas denitrification technology, specifically relating to a flue gas denitrification device for thermal power units. Background Technology

[0002] SNCR (Selective Non-Catalytic Reduction) is a clean denitrification technology that does not use a catalyst. It involves injecting an amino-containing reducing agent (such as ammonia or urea solution) into a furnace at a temperature range of 850–1100°C to reduce and remove NOx from the flue gas, producing nitrogen and water.

[0003] In existing urea denitrification equipment, during the pyrolysis reaction, high-temperature flue gas pyrolyzes with the sprayed urea solution. During the flue gas flow process, heat is lost, and the temperature of the flue gas gradually decreases as it reaches the pyrolysis chamber, preventing a complete pyrolysis reaction and resulting in low pyrolysis efficiency. Therefore, a new type of flue gas denitrification device for thermal power units is needed. Utility Model Content

[0004] To address the aforementioned problems, this utility model discloses a flue gas denitrification device for thermal power units.

[0005] To achieve the above objectives, the technical solution of this utility model is as follows:

[0006] A flue gas denitrification device for thermal power units includes an upper shell. At least two sets of rotary feed assemblies are connected to the bottom of the upper shell, and the bottom of the lowest rotary feed assembly is connected to a lower shell. An air outlet pipe extending from the top of the upper shell is coaxially embedded in the upper shell, and the bottom inlet of the air outlet pipe is lower than all the rotary feed assemblies. The upper shell and the air outlet pipe form an annular space in the inner cavity of the upper shell, and an air inlet pipe tangent to the edge of the annular space extends from the upper shell. A waste liquid collection and discharge assembly is connected to the bottom of the lower shell. Each set of rotary feed assemblies includes an annular cylinder, and a plurality of uniformly distributed annular nozzles are embedded in the annular cylinder. The axis of the nozzles does not intersect with the axis of the annular cylinder. A feed ring is sleeved on the annular cylinder, and the feed ring covers the through hole of the nozzle embedded in the annular cylinder. The feed ring and the annular cylinder form an annular cavity, and a feed pipe tangent to the edge of the annular cavity extends from the feed ring.

[0007] As a preferred embodiment of this invention, the nozzle is tilted in a direction that aligns with the material entering the nozzle inlet as the annular cavity rotates.

[0008] As a preferred embodiment of this utility model, the nozzles of the uppermost set of rotating feeding components are liquid spray nozzles, and the nozzles of the remaining sets of rotating feeding components are air spray nozzles.

[0009] As a preferred embodiment of this utility model, the lower shell is a cone shape with the tip pointing downwards.

[0010] As a preferred technical solution of this utility model, the waste liquid collection and discharge assembly includes a collection tank communicating with the bottom of the lower shell. A piston is slidably installed on the bottom horizontal tube of the collection tank. The piston is provided with a vertical through hole running vertically through the bottom. The bottom horizontal tube of the collection tank is provided with through holes for communicating with the outside atmosphere at both ends of the vertical through hole. The piston extension rod is rotatably connected to a connecting rod, and the other end of the connecting rod is rotatably connected to a drive disk. The drive disk is coaxially connected to a drive motor.

[0011] In a preferred embodiment of this invention, the connecting rod is rotatably connected to the edge connecting post of the drive disc.

[0012] The beneficial effects of this utility model are as follows:

[0013] 1. This application is equipped with a rotary feed assembly that sprays urea solution in Joules and heat-compensating air, so that NOx in the flue gas is reduced by pyrolysis with urea. At the same time, the spraying of heat-compensating air into the flue gas can maintain the temperature of the pyrolysis reaction, so that NOx in the flue gas can be fully pyrolyzed. Furthermore, the nozzles of the same set of rotary feed assemblies are uniformly deflected in an annular shape, so that the sprayed material can drive the flue gas to rotate, thereby improving the overall pyrolysis efficiency.

[0014] Second, this application also includes a waste liquid collection and discharge component, which continuously discharges the solid-liquid mixture generated by pyrolysis from the device under the condition of uninterrupted flue gas pyrolysis, which is convenient and efficient. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present utility model;

[0016] Figure 2 This is a cross-sectional view of the upper housing, air outlet pipe, rotary feeding assembly, and lower housing according to an embodiment of the present utility model;

[0017] Figure 3 This is a schematic diagram of the structure of the rotary feeding assembly according to an embodiment of the present invention;

[0018] Figure 4 This is a schematic diagram of the feed ring structure in an embodiment of the present invention;

[0019] Figure 5 This is a cross-sectional view of the waste liquid collection and discharge assembly according to an embodiment of the present invention.

[0020] List of identifiers in attached diagrams:

[0021] 1. Upper casing; 2. Air outlet duct;

[0022] 3. Rotary feeding assembly; 301. Annular cylinder; 302. Nozzle; 303. Feeding ring;

[0023] 4. Lower casing;

[0024] 5. Waste liquid collection and discharge assembly; 501. Collection tank; 502. Piston; 503. Connecting rod; 504. Drive disc; 505. Drive motor. Detailed Implementation

[0025] The present invention will be further explained below with reference to the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0026] Please see Figure 1-5 A flue gas denitrification device for thermal power units includes an upper shell 1. At least two sets of rotary feed assemblies 3 are connected to the bottom of the upper shell 1, and the bottom of the lowest rotary feed assembly 3 is connected to a lower shell 4. An outlet pipe 2 extending from the top of the upper shell 1 is coaxially embedded in the upper shell 1, and the bottom inlet of the outlet pipe 2 is lower than all the rotary feed assemblies 3. A connecting flange is provided at the top inlet of the outlet pipe 2. The upper shell 1 and the outlet pipe 2 form an annular space within the inner cavity of the upper shell 1, and an inlet pipe extending from the upper shell 1 is tangent to the edge of this annular space. A connecting flange is provided at the inlet of the inlet pipe. A waste liquid collection and discharge assembly 5 is connected to the bottom of the lower shell 4. The upper shell 1, the rotary feed assemblies 3, the lower shell 4, and the waste liquid collection and discharge assembly 5 are connected by flanges and bolts.

[0027] Each rotary feeding assembly 3 includes an annular cylinder 301, with connecting flanges at both the upper and lower interfaces. The annular cylinder 301 is fitted with a plurality of evenly distributed annular nozzles 302, the axes of which do not intersect with the axis of the annular cylinder 301. A feeding ring 303 is fitted over the annular cylinder 301, covering the holes through which the nozzles 302 are embedded. The feeding ring 303 and the annular cylinder 301 form an annular cavity, and the feeding ring 303 extends into a feeding tube tangential to the edge of this annular cavity.

[0028] The inclination direction of nozzle 302 aligns with the inlet of the rotating material entering the annular cavity, and the inlet cross-sectional area of ​​nozzle 302 is more than four times its outlet cross-sectional area. The material fed into the feed ring 303 rotates inside the annular cavity and enters the inlet of nozzle 302 during this rotation. The nozzles 302 of the uppermost rotating feed assembly 3 are liquid spray nozzles, while the nozzles 302 of the remaining rotating feed assembly 3 are air spray nozzles. The uppermost rotating feed assembly 3 sprays urea solution, while the remaining rotating feed assembly 3 sprays heat-compensating air.

[0029] The lower housing 4 is a cone shape with the tip pointing downwards, so that the liquid at the bottom can be discharged into the waste liquid collection and discharge assembly 5.

[0030] The waste liquid collection and discharge assembly 5 includes a collection tank 501 communicating with the bottom of the lower housing 4. A piston 502 is slidably mounted on the bottom horizontal tube of the collection tank 501. The piston 502 has a vertical through hole running vertically through it, and the bottom horizontal tube of the collection tank 501 has through holes at both ends of the vertical through hole for communication with the outside atmosphere. A connecting rod 503 is rotatably connected to the extension rod of the piston 502, and a drive disk 504 is rotatably connected to the other end of the connecting rod 503. A drive motor 505 is coaxially connected to the drive disk 504. The connecting rod 503 is rotatably connected to the edge connecting post of the drive disk 504. The drive motor 505 has several through holes for its own mounting and fixing.

[0031] Working principle:

[0032] In use, the feed pipe of the uppermost set of rotating feed components 3 is connected to the pipeline supplying urea solution, and the feed pipes of the remaining sets of rotating feed components 3 are connected to the pipeline supplying heat compensation air. Then, the air inlet pipe of the upper shell 1 is connected to the pipeline transporting flue gas from the thermal power unit. The flue gas first spirals down around the air outlet pipe 2 in the cavity formed by the upper shell 1, the air outlet pipe 2, the rotating feed components 3, and the lower shell 4, and then enters the air outlet pipe 2 through the bottom inlet and is discharged (the gas discharged from the air outlet pipe 2 enters other treatment equipment or is discharged into the atmosphere). During the spiral descent of the flue gas, the uppermost rotating feed component 3 first sprays urea solution onto the flue gas, so that the NOx in the flue gas is pyrolyzed and reduced by urea. The remaining rotating feed components 3 then spray heat compensation air onto the flue gas to maintain the temperature of the pyrolysis reaction, so that the NOx in the flue gas is fully pyrolyzed. During the spiral descent of the flue gas, under the action of centrifugal force, the solid and liquid centrifuge and collide with the inner wall of the device and flow into the collection tank 501 of the waste liquid collection and discharge component 5.

[0033] The nozzles 302 of the same set of rotary feeding components 3 are uniformly deflected in an annular shape, so that the ejected material can drive the flue gas to rotate.

[0034] While the collection tank 501 continuously collects the solid-liquid mixture (mainly liquid), the drive motor 505 drives the drive disc 504 to rotate at low speed. The rotating drive disc 504 drives the piston 502 to reciprocate in the bottom horizontal tube of the collection tank 501 through the connecting rod 503. When the vertical through hole of the piston 502 is connected to the inner cavity of the collection tank 501, the solid-liquid mixture enters the vertical through hole. When the vertical through hole of the piston 502 is connected to the through hole of the bottom horizontal tube, the solid-liquid mixture in the vertical through hole is discharged to the outside of the device of this application.

[0035] It should be noted that the above content merely illustrates the technical concept of this utility model and cannot be used to limit the scope of protection of this utility model. For those skilled in the art, several improvements and modifications can be made without departing from the principle of this utility model, and all such improvements and modifications fall within the scope of protection of the claims of this utility model.

Claims

1. A flue gas denitrification device for thermal power units, comprising an upper shell (1), characterized in that, The bottom of the upper housing (1) is connected to at least two sets of rotary feeding assemblies (3), and the bottom of the lowest rotary feeding assembly (3) is connected to the lower housing (4). The upper housing (1) is coaxially fitted with an air outlet pipe (2) extending from the top of the upper housing (1), and the bottom inlet of the air outlet pipe (2) is lower than all the rotary feeding assemblies (3). The upper housing (1) and the air outlet pipe (2) form an annular space in the inner cavity of the upper housing (1), and the upper housing (1) extends an air inlet pipe tangent to the edge of the annular space. The bottom of the lower housing (4) is connected to a waste liquid collection and discharge assembly (5). Each of the rotating feed assembly (3) includes an annular cylinder (301), which is inlaid with a plurality of annularly distributed nozzles (302), and the axis of the nozzles (302) does not intersect with the axis of the annular cylinder (301). The annular cylinder (301) is covered with a feed ring (303), and the feed ring (303) covers the through hole of the nozzles (302) inlaid in the annular cylinder (301). The feed ring (303) and the annular cylinder (301) form an annular cavity, and the feed ring (303) extends out a feed tube tangent to the edge of the annular cavity.

2. The flue gas denitrification device for thermal power units according to claim 1, characterized in that, The nozzle (302) is tilted in the direction that the material rotating in the annular cavity enters the inlet of the nozzle (302).

3. The flue gas denitrification device for thermal power units according to claim 1, characterized in that, The nozzle (302) of the topmost set of rotating feed assemblies (3) is a liquid spray nozzle, and the nozzle (302) of the remaining sets of rotating feed assemblies (3) is an air spray nozzle.

4. The flue gas denitrification device for thermal power units according to claim 1, characterized in that, The lower shell (4) is a cone shape with the tip pointing downwards.

5. A flue gas denitrification device for thermal power units according to claim 1, characterized in that, The waste liquid collection and discharge assembly (5) includes a collection tank (501) connected to the bottom of the lower housing (4). A piston (502) is slidably installed on the bottom horizontal tube of the collection tank (501). The piston (502) is provided with a vertical through hole running vertically through the top and bottom. The bottom horizontal tube of the collection tank (501) is provided with through holes for the two ends of the vertical through hole to communicate with the outside atmosphere. The piston (502) extension rod is rotatably connected to a connecting rod (503). The other end of the connecting rod (503) is rotatably connected to a drive disc (504). The drive disc (504) is coaxially connected to a drive motor (505).

6. The flue gas denitrification device for thermal power units according to claim 5, characterized in that, The connecting rod (503) is rotatably connected to the edge connecting post of the drive disc (504).

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