Low-temperature wet denitration liquid supply system
By adopting a partitioned storage tank design and an inclined pipeline structure in the low-temperature wet denitrification liquid supply system, the problems of denitrification liquid freezing and equipment resonance in winter were solved, improving the system's stability and automation level, and reducing energy consumption and maintenance costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA ACAD OF AEROSPACE AERODYNAMICS
- Filing Date
- 2026-03-27
- Publication Date
- 2026-06-05
AI Technical Summary
Existing low-temperature wet denitrification liquid supply systems suffer from problems such as reduced delivery efficiency, resonance between the circulating pump and the pipeline, and freezing of the denitrification liquid when operating in northern winters due to unreasonable pipeline layout, which affects the stable operation of the system.
The system uses a storage tank to separate the supply and return zones. Combined with a circulating pump, expansion joint, and inclined supply and return pipelines, it ensures stable circulation of the denitrification liquid and absorbs equipment vibration and thermal expansion and contraction through the expansion joint to prevent freezing.
It improves the system's operational reliability in cold environments, reduces operating energy consumption and maintenance costs, achieves automated control, and ensures long-term stable operation.
Smart Images
Figure CN122141434A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of exhaust gas treatment equipment technology, and in particular to a low-temperature wet denitrification liquid supply system, which is suitable for exhaust gas denitrification treatment in industrial facilities such as electric arc wind tunnels. Background Technology
[0002] Currently, industrial waste gas from certain industries contains NOx, and when the concentration exceeds the standard, it cannot be directly discharged and must undergo denitrification treatment. Conventional denitrification devices generally have the following problems: they require flue gas temperatures above 300℃, oxidize NO by injecting hydrogen peroxide or ammonia, and then absorb it in a denitrification tower; the consumption of denitrification agents is large, the operating cost is high, and the waste gas is prone to carrying a large amount of free ammonia during emission; the overall process is complex, the investment is high, and the energy consumption is large; the equipment suffers from severe corrosion, the level of automation is low, and it is difficult for the device to achieve continuous and stable operation.
[0003] Low-temperature wet denitrification technology overcomes the shortcomings of conventional wet methods. The denitrification liquid can be recycled, and the NOx treatment capacity can be flexibly adjusted by spray density and denitrification liquid concentration, facilitating automated control. It offers advantages such as energy saving and zero wastewater discharge. The liquid supply system is a key component of the low-temperature wet denitrification process, requiring the function of transporting and recovering the denitrification liquid between the storage tank and the denitrification tower. Existing liquid supply systems, when operating in northern winters, suffer from problems such as decreased transport efficiency, resonance between the circulating pump and pipelines, and freezing of the denitrification liquid due to unreasonable pipeline layout, connection structure, and reflux design, affecting the stable operation of the system. Summary of the Invention
[0004] The purpose of this invention is to provide a low-temperature wet denitrification liquid supply system that can solve the above-mentioned technical problems.
[0005] This invention provides a low-temperature wet denitrification liquid supply system, comprising: The liquid storage tank is internally divided into a supply area and a return area by a partition wall; At least one circulation pump is installed in the liquid supply area; The liquid supply pipeline is connected at one end to the outlet of the circulating pump and at the other end to the interior of the denitrification tower; The pipeline inside the tower is installed at the top of the partition of the denitrification tower and connected to the liquid supply pipeline, and is used to spray the denitrification liquid evenly into the tower. A return liquid pipeline connects the bottom of the denitrification tower to the return liquid zone; An expansion joint is installed between the circulating pump and the liquid supply pipeline; A valve is installed between the expansion joint and the liquid supply line; The supply pipeline and the return pipeline are arranged at an angle, and the outlet of the return pipeline extends below the liquid surface of the return zone.
[0006] Preferably, the liquid storage tank is located underground and is covered with an insulation layer.
[0007] Preferably, the partition wall has a connecting hole for connecting the liquid supply area and the liquid return area.
[0008] Preferably, the number of circulating pumps is the same as the number of layers in the denitrification tower, and each circulating pump independently corresponds to the liquid supply pipeline of one layer of the denitrification tower.
[0009] Preferably, the pipeline inside the tower includes a main pipe, branch pipes and nozzles. The main pipe is connected to the liquid supply pipeline, the branch pipes are distributed on both sides of the main pipe, and the nozzles are installed on the branch pipes.
[0010] Preferably, the main pipe, the branch pipe and the nozzle are connected by a movable connection structure.
[0011] Preferably, the liquid supply pipeline has an inclination angle of 5° to 15° in the horizontal direction, with its lowest point facing the liquid storage tank.
[0012] Preferably, the upstream of the return liquid pipeline is sealed to the bottom of the denitrification tower, and the downstream enters the return liquid zone. The bottom plate of the denitrification tower and the return liquid pipeline are inclined at 5° to 15°.
[0013] Preferably, the outlet of the return pipeline is located 0.5 meters to 1.5 meters below the liquid surface in the return zone.
[0014] Preferably, the head of the circulating pump is higher than the total height of its corresponding denitrification tower layer.
[0015] Beneficial effects: This invention ensures stable diversion and continuous supply of denitrification liquid during circulation by dividing the storage tank into a supply zone and a return zone, combined with the internal structure of the circulating pump. The supply and return pipelines are arranged at an angle, and the return pipe outlet extends below the liquid surface, effectively avoiding the risk of liquid accumulation and freezing in winter, significantly improving operational reliability in cold environments. An expansion joint is installed between the circulating pump and the supply pipeline to effectively absorb thermal expansion and contraction of the pipeline and equipment vibration, preventing resonance and extending equipment life. The overall structure is compact and rationally laid out, facilitating automated control, reducing operating energy consumption and maintenance costs, and ensuring long-term stable operation of the system under low-temperature conditions. Attached Figure Description
[0016] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0017] Figure 1 This is a schematic diagram of the low-temperature wet denitrification liquid supply system of the present invention; Figure 2 This is a schematic diagram of the liquid storage tank structure of the present invention; Figure 3 This is a schematic diagram of the internal pipeline structure of the tower of the present invention.
[0018] Explanation of reference numerals in the attached diagram: 1-Storage tank, 11-Return area, 12-Partition wall, 13-Supply area, 14-Connecting hole, 2-Circulation pump, 3-Expansion joint, 4-Valve, 5-Supply pipeline, 6-Inner tower pipeline, 61-Main pipe, 62-Branch pipe, 63-Nozzle, 7-Return pipeline. Detailed Implementation
[0019] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0020] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.
[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral connection; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; and they may refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0022] Example A low-temperature wet denitrification liquid supply system, such as Figure 1 As shown, it includes a liquid storage tank 1, five circulating pumps 2, five expansion joints 3, five valves 4, five sets of supply pipelines 5, five sets of internal tower pipelines 6, and one set of return pipelines 7. Among them: Storage tank 1, volume 100m³ 3 It is a sealed tank with an anti-corrosion lining, responsible for providing denitrification solution and storing returned denitrification solution; The circulating pump 2 is placed in the storage tank to deliver the denitrification liquid to the supply pipeline 5; Expansion joint 3 is installed at the outlet of circulating pump 2 to eliminate the impact of vibration of circulating pump 2 on liquid supply line 5; Valve 4 is installed at the outlet of expansion joint 3 and is used to control the operation and stop of liquid supply line 5; The upstream of the liquid supply pipeline 5 is connected to valve 4, and the downstream is connected to pipeline 6 inside the tower. Pipeline 6 inside the tower is located at the top of the partition of the denitrification tower, providing uniform denitrification liquid inside the tower; The return liquid pipeline 7 is located at the bottom of the denitrification tower and is responsible for collecting all the liquid in the tower and transporting it back to the storage tank 1.
[0023] The denitrification liquid is sprayed from top to bottom in the denitrification tower and fully mixed with the NOx-containing tail gas coming from bottom to top to achieve oxidation and denitrification. The denitrification liquid after reacting with the tail gas is returned to the storage tank 1.
[0024] The storage tank 1 should be placed underground and subjected to active heating and passive insulation to prevent the denitrification liquid from freezing in winter. Active heating should be achieved using conventional electric heating, while the storage tank should be covered with an insulation layer for passive insulation. Figure 2 As shown, the liquid storage tank 1 is equipped with a partition wall 12, which divides the internal space into a liquid supply area 13 and a liquid return area 11. The liquid supply area has a volume of 60m³. 3 The volume of the return liquid area is 40m³. 3 The partition wall 12 is provided with a connecting hole 14, which has a diameter of 20cm and is 50cm from the bottom of the pool. The function of the connecting hole is to connect the liquid in the supply area 13 and the return area 11 to keep the liquid level consistent.
[0025] like Figure 3 It can be seen that the pipeline 6 inside the tower consists of a main pipe 61, branch pipes 62, and nozzles 63, all made of PPR. The connections between the main pipe 61, branch pipes 62, and nozzles 63 are sealed with threads for easy disassembly and maintenance. The nozzles are evenly distributed and have a shower head structure to ensure uniform spraying of the denitrification liquid.
[0026] It should be noted that in this embodiment, five circulating pumps 2 are connected one-to-one to the five denitrification tower layers. The head of the five circulating pumps from low to high is 20m, 20m, 45m, 45m, and 45m respectively. The top height of the five denitrification tower layers from low to high is 5m, 10m, 15m, 20m, and 25m respectively.
[0027] It should be noted that in this embodiment, the liquid supply line 5 is inclined at 10°. Figure 1 (Center b angle = 10°) to prevent denitrification liquid from remaining in the pipeline and causing freezing in winter.
[0028] It should be noted that in this embodiment, the upstream of the return liquid pipeline 7 is sealed to the bottom of the denitrification tower, and the downstream enters the return liquid zone 11. The bottom plate of the denitrification tower and the return liquid pipeline are inclined at 10°. Figure 1 (Angle a = 10°) to prevent the denitrification liquid from remaining at the bottom of the denitrification tower and in the pipeline, causing freezing in winter.
[0029] It should be noted that in this embodiment, the outlet of the return liquid pipeline 7 is located 1m below the liquid surface to prevent the tail gas in the denitrification tower from entering the storage tank 1.
[0030] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.
Claims
1. A low-temperature wet denitrification liquid supply system, characterized in that, include: The liquid storage tank is internally divided into a supply area and a return area by a partition wall; At least one circulation pump is installed in the liquid supply area; The liquid supply pipeline is connected at one end to the outlet of the circulating pump and at the other end to the interior of the denitrification tower; The pipeline inside the tower is installed at the top of the partition of the denitrification tower and connected to the liquid supply pipeline, and is used to spray the denitrification liquid evenly into the tower. A return liquid pipeline connects the bottom of the denitrification tower to the return liquid zone; An expansion joint is installed between the circulating pump and the liquid supply pipeline; A valve is installed between the expansion joint and the liquid supply line; The supply pipeline and the return pipeline are arranged at an angle, and the outlet of the return pipeline extends below the liquid surface of the return zone.
2. The low-temperature wet denitrification liquid supply system according to claim 1, characterized in that, The liquid storage tank is located underground and is covered with an insulation layer.
3. The low-temperature wet denitrification liquid supply system according to claim 1, characterized in that, The partition wall has a connecting hole for connecting the liquid supply area and the liquid return area.
4. The low-temperature wet denitrification liquid supply system according to claim 1, characterized in that, The number of circulating pumps is the same as the number of layers in the denitrification tower, and each circulating pump independently corresponds to the liquid supply pipeline of one layer of the denitrification tower.
5. The low-temperature wet denitrification liquid supply system according to claim 1, characterized in that, The pipeline inside the tower includes a main pipe, branch pipes and nozzles. The main pipe is connected to the liquid supply pipeline, the branch pipes are distributed on both sides of the main pipe, and the nozzles are installed on the branch pipes.
6. The low-temperature wet denitrification liquid supply system according to claim 5, characterized in that, The main pipe, the branch pipe, and the nozzle are connected by a movable connection structure.
7. The low-temperature wet denitrification liquid supply system according to claim 1, characterized in that, The liquid supply pipeline has a horizontal inclination angle of 5° to 15°, with its lowest point facing the liquid storage tank.
8. The low-temperature wet denitrification liquid supply system according to claim 1, characterized in that, The upstream of the return liquid pipeline is sealed to the bottom of the denitrification tower, and the downstream enters the return liquid zone. The bottom plate of the denitrification tower and the return liquid pipeline are inclined at 5° to 15°.
9. The low-temperature wet denitrification liquid supply system according to claim 1, characterized in that, The outlet of the return pipeline is located 0.5 to 1.5 meters below the liquid surface in the return zone.
10. The low-temperature wet denitrification liquid supply system according to claim 1, characterized in that, The head of the circulating pump is higher than the total height of its corresponding denitrification tower layer.