A multi-stage recovery and treatment device for nitric acid tail gas
By designing a multi-stage recovery and treatment device for nitric acid tail gas, and utilizing multi-stage neutralization and purification components and various treatment units, the problem of low efficiency in the traditional water absorption method is solved, achieving efficient tail gas purification and safe treatment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 安瑞森(宁夏)电子材料有限公司
- Filing Date
- 2025-07-31
- Publication Date
- 2026-06-30
AI Technical Summary
Traditional nitric acid tail gas purification devices use water absorption, resulting in low purification efficiency and inability to completely remove harmful gases. This poses environmental pollution and health risks to personnel, making it difficult to meet the high standards required by modern factories.
A multi-stage recovery and treatment device for nitric acid tail gas is designed. The device uses purification components for multi-stage neutralization and purification. It employs components such as induced draft fans, circulating pumps, heating devices, and ammonia reducers to gradually separate and absorb harmful components, ensuring that pollutants are in full contact with the neutralizing agent and improving the uniformity and thoroughness of the reaction.
It significantly improves the purification efficiency of nitric acid tail gas, achieves the step-by-step removal of harmful gases, ensures environmental safety and personnel health, and meets the high standards required by modern factories.
Smart Images
Figure CN224422446U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of nitric acid tail gas recovery technology, and in particular to a multi-stage recovery and treatment device for nitric acid tail gas. Background Technology
[0002] The development of the nitric acid industry has accelerated, with total output growing at a rate of 10% to 15% annually. The nitric acid industry has entered a period of rapid development, with an annual growth rate of 15% to 20%. However, this rapid development has also led to increasingly severe environmental pollution from nitric acid waste gas emissions. This waste gas consists of NOx from various industrial waste gases, including tail gas, flue gas, and lime air generated during the production process. The nitric acid production process generates a large amount of waste gas containing NOx. The commonly referred to ammonia oxides (NOx) mainly include NO, NO2, N2O, N2O3, N2O4, and N2O5.
[0003] Traditional nitric acid tail gas purification devices mostly use water absorption to treat the tail gas. However, this purification method has many shortcomings. Because nitric acid tail gas is highly acidic, water is easily acidified during the absorption process, leading to a significant decrease in subsequent absorption efficiency. This makes it impossible to completely purify the tail gas, and the residual harmful gases emitted into the air will cause environmental pollution. It also poses a threat to the health of on-site workers, presenting significant environmental and safety hazards. It is difficult to meet the high standards of modern factories and is inconvenient to use. Utility Model Content
[0004] The purpose of this invention is to provide a multi-stage recovery and treatment device for nitric acid tail gas, which can avoid the problem that traditional nitric acid tail gas purification devices mostly use water absorption, but because nitric acid tail gas is highly acidic, the absorption water is easily acidified, reducing the purification efficiency, failing to completely remove harmful gases, posing environmental pollution and health risks to personnel, and failing to meet the high standards required by modern factories.
[0005] This utility model provides a multi-stage recovery and treatment device for nitric acid tail gas, including a recovery tank. A first air inlet pipe is connected to the outer surface of the front side of the recovery tank. A purification component is provided on the outer surface of the top of the recovery tank. The purification component includes an induced draft fan. An air supply pipe is connected to the top of the recovery tank. The air supply end of the induced draft fan is fixedly connected to one end of the air supply pipe. A circulation pump in contact with the ground is installed on the left side of the recovery tank. The water inlet and outlet of the circulation pump are both connected to the inner cavity of the recovery tank through pipelines.
[0006] In one specific implementation, a heating device and an ammonia reducer that are in contact with the ground are respectively installed on the rear and left sides of the recovery tank. Two exhaust gas fans that are in contact with the ground are respectively installed on the opposite side of the recovery tank, the heating device and the ammonia reducer. The exhaust gas fans are interconnected with the recovery tank, the heating device and the ammonia reducer through pipelines. A second air inlet pipe is connected to the outer surface of the front side of the heating device.
[0007] In one specific implementation, the outer surface of the recycling tank is connected to a water inlet pipe, and the outer surface of the recycling tank is connected to a drain pipe.
[0008] In one specific implementation, a motor is fixedly connected to the bottom of the recycling tank, and a rotating disk is slidably connected to the inner cavity of the recycling tank.
[0009] In one specific implementation, a circular pipe is fixedly connected to the inner cavity of the rotating disk, and a water pump is fixedly connected to the outer surface of the recycling tank. The water delivery end of the water pump is connected to the inner cavity of the circular pipe through a flexible hose.
[0010] In one specific implementation, a plurality of connecting rods are fixedly connected to the inner side of the rotating disk, and a first placement disk is fixedly connected to one end of each connecting rod.
[0011] In one specific implementation, the bottom of the rotating disk is fixedly connected to several connecting pipes, and the top of the connecting pipes is fixedly connected to the inner cavity of the circular tube. Several nozzles are fixedly connected to the outer surfaces of the connecting pipes and the circular tube respectively.
[0012] In one specific implementation, a second placement plate is fixedly connected to the end of the connecting pipe away from the circular pipe, a rotating rod is fixedly connected to the output shaft of the motor, and the top end of the rotating rod penetrates into the inner cavity of the recovery tank and is fixedly connected to the bottom of the first placement plate. Two stirring blades arranged symmetrically in an upper and lower position are fixedly connected to the outer surface of the rotating rod.
[0013] The beneficial effects of this application are as follows: By setting up a purification component, not only can nitric acid tail gas be subjected to multi-stage and repeated neutralization and purification treatment, but also harmful components in the tail gas can be gradually separated and efficiently absorbed at different treatment stages, thereby significantly improving the overall purification efficiency. This allows pollutants in the gas to be removed step by step through repeated neutralization and purification. During the neutralization reaction, the purification component ensures uniform settling and full diffusion of the tail gas within the purification area, guaranteeing that pollutants can fully contact the neutralizing agent and undergo a highly efficient reaction, further improving the uniformity, stability, and thoroughness of the chemical reaction, and facilitating its use. Attached Figure Description
[0014] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.
[0015] Figure 1 This is a three-dimensional schematic diagram of the overall structure of an embodiment of the present utility model;
[0016] Figure 2 This is a bottom-view perspective view of the structure of the recycling tank according to an embodiment of the present invention;
[0017] Figure 3 This is a three-dimensional side view sectional view of the recycling tank structure according to an embodiment of the present utility model;
[0018] Figure 4 This is a side sectional view of the rotating disk structure according to an embodiment of the present utility model;
[0019] Figure 5 This is a three-dimensional schematic diagram of the rotating rod structure according to an embodiment of the present utility model;
[0020] Figure 6 This is a three-dimensional schematic diagram of the second placement tray structure according to an embodiment of the present utility model.
[0021] Icons: 1. Recycling tank; 11. First air intake pipe; 2. Purification component; 21. Exhaust fan; 22. Air supply pipe; 23. Circulation pump; 24. Water inlet pipe; 25. Drain pipe; 26. Motor; 27. Rotary disc; 28. Circular pipe; 29. Water pump; 210. Connecting rod; 211. First placement plate; 212. Connecting pipe; 213. Nozzle; 214. Second placement plate; 215. Rotating rod; 216. Stirring blades; 3. Heating device; 31. Second air intake pipe; 4. Ammonia reducer; 5. Exhaust fan. Detailed Implementation
[0022] Traditional nitric acid tail gas purification devices mostly employ water absorption, but due to the strong acidity of nitric acid tail gas, the absorption water is easily acidified rapidly, reducing purification efficiency and failing to completely remove harmful gases. This poses environmental pollution and health risks to personnel, making it difficult to meet the high standards required by modern factories. Therefore, the inventors have developed a multi-stage recovery and treatment device for nitric acid tail gas. The purification components are designed to perform multi-stage, repeated neutralization treatment on the nitric acid tail gas, gradually separating and absorbing harmful components at different stages, significantly improving purification efficiency. This component ensures uniform settling and full diffusion of the tail gas, guaranteeing sufficient contact between pollutants and the neutralizing agent, improving the uniformity and thoroughness of the reaction, achieving a highly efficient and stable purification effect, facilitating practical application, and thus solving the aforementioned shortcomings.
[0023] The following detailed description, in conjunction with the accompanying drawings, outlines some embodiments of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0024] Please refer to Figures 1 to 6This utility model provides a multi-stage nitric acid tail gas recovery and treatment device, including a recovery tank 1. A first air inlet pipe 11 is connected to the outer surface of the front side of the recovery tank 1. This first air inlet pipe 11 is connected to a fume collector storing nitric acid tail gas and a storage device for directly storing nitric acid tail gas. A purification component 2 is provided on the outer surface of the top of the recovery tank 1. The purification component 2 includes an induced draft fan 21, which is fixedly connected to the outer surface of the top of the recovery tank 1. An air delivery pipe 22 is connected to the top of the recovery tank 1. The air delivery end of the induced draft fan 21 is fixedly connected to one end of the air delivery pipe 22, thereby facilitating the injection of nitric acid tail gas into the bottom of the inner cavity of the recovery tank 1 for neutralization. A circulation pump 23, in contact with the ground, is installed on the left side of the recovery tank 1. The inlet and outlet of the circulation pump 23 are connected to the inner cavity of the recovery tank 1 via pipelines. A heating device 3 and an ammonia reducer 4, also in contact with the ground, are installed on the rear and left sides of the recovery tank 1, respectively. Two exhaust gas blowers 5, in contact with the ground, are installed on opposite sides of the recovery tank 1, heating device 3, and ammonia reducer 4. These exhaust gas blowers 5 are connected to the recovery tank 1, heating device 3, and ammonia reducer 4 via pipelines to facilitate the transfer of nitric acid exhaust gas for multi-stage recovery treatment. The ammonia reducer 4 has its own exhaust and inlet ports. A second intake pipe 31 is connected to the outer surface of the front side of the heating device 3. 1 is used to connect with an external ammonia storage device to mix and heat the neutralized nitric acid tail gas. The heating device 3 itself has an outlet and an inlet. The outer surface of the recovery tank 1 is connected to a water inlet pipe 24, which is used to introduce external cooling liquid and cool the absorbent liquid by introducing chilled water to keep the temperature below 15 degrees Celsius. The absorbent liquid is ultrapure water stored inside the recovery tank 1. The outer surface of the recovery tank 1, below the water inlet pipe 24, is also connected to a liquid inlet pipe, which facilitates the introduction of ultrapure water into the recovery tank 1 for neutralization with the nitric acid tail gas. The outer surface of the recovery tank 1 is connected to a drain pipe 25, which is used to discharge the neutralized waste gas. The bottom of the recovery tank 1 is fixedly connected to a motor 26. A rotating disk 27 is slidably connected to the inner cavity of the recovery tank 1. A round pipe 28 is fixedly connected to the inner cavity of the rotating disk 27. A water pump 29 is fixedly connected to the outer surface of the recovery tank 1. The water delivery end of the water pump 29 is connected to the inner cavity of the round pipe 28 through a hose. The water inlet end of the water pump 29 is connected to an external agent or liquid for settling nitric acid tail gas through a pipe. Several connecting rods 210 are fixedly connected to the inner side of the rotating disk 27. One end of the connecting rod 210 is fixedly connected to a first placement plate 211. Several connecting pipes 212 are fixedly connected to the bottom of the rotating disk 27, and the top end of the connecting pipe 212 is fixedly connected to the inner cavity of the round pipe 28.
[0025] Please refer to Figures 2 to 6A number of nozzles 213 are fixedly connected to the outer surfaces of the connecting pipe 212 and the round pipe 28 respectively. A second placement plate 214 is fixedly connected to the end of the connecting pipe 212 away from the round pipe 28. A rotating rod 215 is fixedly connected to the output shaft of the motor 26. The top end of the rotating rod 215 penetrates into the inner cavity of the recovery tank 1 and is fixedly connected to the bottom of the first placement plate 211. The area of the rotating rod 215 in contact with the recovery tank 1 is sealed. Two stirring blades 216 are fixedly connected to the outer surface of the rotating rod 215 in a symmetrical arrangement.
[0026] Specifically, when nitric acid tail gas enters recovery tank 1, water pump 29 is started to discharge the external settled liquid into circular pipe 28, which then transports it to connecting pipe 212 and nozzle 213. At this time, motor 26 is started, which drives rotating rod 215 and stirring blade 216 to swing left and right. Rotating rod 215 simultaneously drives first placement plate 211, second placement plate 214 and rotating plate 27 to swing synchronously, thereby driving multiple nozzles 213 to swing left and right, achieving uniform spraying of settled liquid. In this way, nitric acid tail gas is effectively settled and introduced into ultrapure water at the bottom of recovery tank 1 for neutralization treatment. At the same time, stirring blade 216 mixes and stirs the liquid, accelerating the neutralization reaction and facilitating use.
[0027] In summary, the working principle of the multi-stage nitric acid tail gas recovery and treatment device of this utility model embodiment is as follows: First, the collected nitric acid tail gas enters the recovery tank 1 through the first inlet pipe 11. The purification component 2 gradually causes the nitric acid tail gas to settle to the bottom of the inner cavity of the recovery tank 1, and neutralizes it with stored ultrapure water. At this point, the nitric acid tail gas is the first-stage tail gas. The circulation pump 23 is started to discharge the neutralized nitric acid tail gas at the bottom back into the top of the recovery tank 1 to achieve uniform neutralization. During the neutralization process, a chilled liquid can be introduced to cool the ultrapure water, keeping the temperature below 15°C. The tail gas after neutralization is upgraded to the second-stage tail gas. Then, the tail gas fan 5 is started to send the second-stage tail gas into the heating device 3 to be heated to 175–185°C, and mixed with externally supplied ammonia gas at an ammonia-nitrogen volume ratio of 1:1.0–1.4. After heating and mixing, the gas is sent to the ammonia reducer 4 for reduction reaction. The reacted tail gas is directly vented, thereby realizing the multi-stage recovery and treatment of nitric acid tail gas.
[0028] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. A multi-stage recovery and treatment device for nitric acid tail gas, characterized in that, The system includes a recycling tank (1), the outer surface of the front side of the recycling tank (1) is connected to a first air inlet pipe (11), the outer surface of the top of the recycling tank (1) is provided with a purification component (2), the purification component (2) includes an exhaust fan (21), the top of the recycling tank (1) is connected to an air supply pipe (22), the air supply end of the exhaust fan (21) is fixedly connected to one end of the air supply pipe (22), a circulation pump (23) in contact with the ground is installed on the left side of the recycling tank (1), the water inlet and water outlet of the circulation pump (23) are connected to the inner cavity of the recycling tank (1) through pipelines.
2. The multi-stage recovery and treatment device for nitric acid tail gas according to claim 1, characterized in that, The recovery tank (1) is equipped with a heating device (3) and an ammonia reducer (4) that are in contact with the ground on the rear and left sides, respectively. Two exhaust gas fans (5) that are in contact with the ground are installed on opposite sides of the recovery tank (1), the heating device (3) and the ammonia reducer (4), and the exhaust gas fans (5) are connected to the recovery tank (1), the heating device (3) and the ammonia reducer (4) through pipelines. The outer surface of the front side of the heating device (3) is connected to a second air inlet pipe (31).
3. The multi-stage recovery and treatment device for nitric acid tail gas according to claim 1, characterized in that, The outer surface of the recycling tank (1) is connected to a water inlet pipe (24), and the outer surface of the recycling tank (1) is connected to a drain pipe (25).
4. The multi-stage recovery and treatment device for nitric acid tail gas according to claim 3, characterized in that, A motor (26) is fixedly connected to the bottom of the recycling tank (1), and a rotating disk (27) is slidably connected to the inner cavity of the recycling tank (1).
5. The multi-stage recovery and treatment device for nitric acid tail gas according to claim 4, characterized in that, The inner cavity of the rotating disk (27) is fixedly connected to a round pipe (28), and the outer surface of the recycling tank (1) is fixedly connected to a water pump (29). The water delivery end of the water pump (29) is connected to the inner cavity of the round pipe (28) through a flexible hose.
6. The multi-stage recovery and treatment device for nitric acid tail gas according to claim 5, characterized in that, A plurality of connecting rods (210) are fixedly connected to the inner side of the rotating disk (27), and a first placement disk (211) is fixedly connected to one end of each connecting rod (210).
7. The multi-stage recovery and treatment device for nitric acid tail gas according to claim 6, characterized in that, The bottom of the rotating disk (27) is fixedly connected to several connecting pipes (212), and the top of the connecting pipes (212) is fixedly connected to the inner cavity of the round pipe (28). Several nozzles (213) are fixedly connected to the outer surfaces of the connecting pipes (212) and the round pipe (28).
8. The multi-stage recovery and treatment device for nitric acid tail gas according to claim 7, characterized in that, The end of the connecting pipe (212) away from the round pipe (28) is fixedly connected to a second placement plate (214). The output shaft of the motor (26) is fixedly connected to a rotating rod (215), and the top end of the rotating rod (215) penetrates into the inner cavity of the recovery tank (1) and is fixedly connected to the bottom of the first placement plate (211). Two stirring blades (216) arranged symmetrically in the upper and lower positions are fixedly connected to the outer surface of the rotating rod (215).