Flue gas recirculation device
By introducing spiral steel plates, cooling pipes and filters into the flue gas recirculation device, the problems of low mixing efficiency and difficulty in cleaning of existing devices are solved, and the full mixing of flue gas and air is achieved and the combustion stability is improved.
Patent Information
- Application Number
- CN202323336452.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-07
- Publication Date
- 2024-12-10
- Estimated Expiration
- 2033-12-07
AI Technical Summary
The existing flue gas recirculation device is inefficient when mixing flue gas and air, resulting in unstable combustion and difficult to clean, affecting the reduction of nitrogen oxide concentration.
A flue gas recirculation device including a bracket, shell, hollow column, spiral steel plate, cooling tube and filter grid is designed to promote gas mixing through spiral steel plates, the cooling tube controls the flue gas temperature, and the filter grid improves the flue gas purity to ensure mixing. Even and clean.
The full mixing of flue gas and air is achieved, the nitrogen oxide concentration is reduced, the combustion stability and flue gas purity are improved, and the cleaning process is simplified.
Smart Images
Figure CN222143108U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of flue gas circulation, and more specifically relates to a flue gas recirculation device. Background Art
[0002] There are three ways for coal-fired boilers to generate nitrogen oxides during combustion: thermal, rapid, and fuel. Thermal is the oxidation of nitrogen in the air at high temperatures to generate nitrogen oxides. Rapid is the reaction of nitrogen in the air with hydrocarbon ions (-HC) in the fuel to generate nitrogen oxides. Fuel is the thermal decomposition of nitrogen compounds contained in the fuel during combustion and then oxidation to generate nitrogen oxides. The nitrogen oxides generated by coal-fired boilers are mainly fuel-based, followed by thermal, and the least rapid. The concentration of nitrogen oxides is mainly affected by temperature and oxygen concentration during burner combustion. In order to reduce the concentration of nitrogen oxides and meet emission standards, a part of low-temperature flue gas will be extracted before the air preheater and sent into the furnace together with air. This method can not only reduce the combustion temperature, but also reduce the oxygen concentration, thereby reducing the concentration of nitrogen oxides. When the existing flue gas recirculation device cannot mix the flue gas and air well, it is easy to cause unstable combustion of the subsequent burner, and a higher concentration of nitrogen oxides will still be generated.
[0003] For example, in the flue gas recirculation device of patent application number CN202222914169.0, the smoke enters the smoke inlet part through the smoke inlet pipe, and the air enters the air inlet plate through the air inlet pipe. The air is discharged from the air holes on the air inlet plate under the action of pressure and enters the mixing box. Then, the air enters the smoke inlet part from the opening at one end of the smoke inlet part along the outer wall of the air outlet pipe. When the air flows, it mixes with the smoke discharged from the smoke outlet. At the same time, the length block is not surrounded by a circle, so that part of the air and smoke continue to move along the outer wall of the length block. Part of the air and smoke does not move along the outer wall of the length block, and first enters the space between the air outlet pipe and the inner wall of the smoke inlet and is spread. When the air and smoke that subsequently move along the outer wall of the length block enter the space between the air outlet pipe and the inner wall of the smoke inlet, they are mixed with the already spread smoke and air, and then are discharged from the air outlet pipe 10. During the entire process, the air is constantly flowing, which will drive the smoke to continuously mix with the air from the smoke outlet, effectively mixing the smoke into the air, thereby maintaining the stability of subsequent combustion, reducing the concentration of nitrogen oxides, and thus meeting emission standards.
[0004] Although the above-mentioned flue gas recirculation device can solve the problem of flue gas mixing and ensure the stable combustion of subsequent flue gas, its internal cleaning is relatively difficult, and the mixing uniformity during the mixing process also depends heavily on natural mixing, which still needs to be improved. Utility Model Content
[0005] In order to solve the above technical problems, the utility model provides a flue gas recirculation device.
[0006] The utility model provides a flue gas recirculation device, comprising a bracket, an outer shell is sleeved on the inner side of the bracket, and a smoke pipe and an air inlet pipe are fixedly arranged at the lower end of the outer shell; a hollow column is fixedly arranged at the inner center of the bracket; a pair of air vents are symmetrically arranged on the upper side of the hollow column; a baffle is fixedly arranged on the inner side of the hollow column below the air vent; an air outlet pipe is fixedly arranged on the upper end of the hollow column; and the device also includes a spiral steel plate fixedly arranged on the outer circumference of the hollow column; the spiral steel plate is a stainless steel thin plate; the spiral steel plate is fixedly connected to the inner side of the outer shell; the upper end of the spiral steel plate is lower than the air vent; the lower end of the air outlet pipe is elastically connected to a booster block.
[0007] Preferably, a cooling pipe is fixedly provided at the lower end of the hollow column located at the baffle, and the lower end of the cooling pipe is fixedly connected to a cooling device; and a wire hole is opened at the center of the lower end of the shell.
[0008] Preferably, the upper end of the shell is threadedly connected to a water plug 1; and the lower end of the shell is threadedly connected to a water plug 2.
[0009] Preferably, filter screen 2 is fixedly arranged on the inner side of the smoke pipe, and filter screen 1 is fixedly arranged on the inner side of the air intake pipe.
[0010] Compared with the prior art, the beneficial effects of the present invention are:
[0011] (1) By setting a spiral steel plate and utilizing the spiral space formed by the spiral steel plate, the hollow column and the outer shell, the gas must go through a spiral upward movement to flow out after being input. In the process of promoting the movement of the gas, the flue gas and air are fully mixed;
[0012] (2) By setting a cooling pipe, the cooling pipe absorbs heat through the hollow column, so that the hot flue gas is cooled to the required temperature and then discharged. This can effectively control the output temperature of the flue gas recirculation and prevent the output flue gas from overheating and affecting the use of the mixed flue gas;
[0013] (3) By setting water plugs 1 and 2, the inner side of the shell is easy to clean, thereby ensuring the purity of the output flue gas and preventing tiny particles in the previous flue gas from interfering with the subsequent flue gas recirculation; by setting filter screens 1 and 2, tiny particles mixed in the flue gas and air can be filtered out before entering the inner side of the shell, thereby preventing them from affecting the purity of the output flue gas. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a schematic diagram of the overall structure of the utility model;
[0015] Figure 2 It is a schematic diagram of the internal structure of the utility model;
[0016] Figure 3 This is a schematic diagram of the spiral steel plate structure of the utility model.
[0017] Explanation of the numbers in the figure: 10. bracket; 11. shell; 12. water plug 1; 13. spiral steel plate; 14. hollow column; 15. cooling pipe; 16. air vent; 17. baffle; 18. booster block; 19. cooling equipment; 20. wire hole; 21. water plug 2; 22. flue gas pipe; 23. air inlet pipe; 24. filter screen 1; 25. filter screen 2; 26. outlet pipe. DETAILED DESCRIPTION
[0018] Specific embodiment 1: Please refer to Figure 1-3 A flue gas recirculation device includes a bracket 10, a shell 11 is sleeved inside the bracket 10, and a flue gas pipe 22 and an air inlet pipe 23 are fixedly arranged at the lower end of the shell 11; a hollow column 14 is fixedly arranged at the center of the inner side of the bracket 10; a pair of vents 16 are symmetrically arranged on the upper side of the hollow column 14; a baffle 17 is fixedly arranged below the vents 16 on the inner side of the hollow column 14; an air outlet pipe 26 is fixedly arranged at the upper end of the hollow column 14; and a spiral steel plate is fixedly arranged on the outer circumference of the hollow column 14 13; the spiral steel plate 13 is a stainless steel thin plate; the spiral steel plate 13 is fixedly connected to the inner side of the shell 11; the upper end of the spiral steel plate 13 is lower than the vent 16; the lower end of the outlet pipe 26 is elastically connected to the booster block 18 through a spring; by setting the spiral steel plate 13 and utilizing the spiral space surrounded by the spiral steel plate 13, the gas must undergo a spiral upward movement to flow out after being input, and in the process of promoting the movement of the gas, the smoke and air are fully mixed.
[0019] See also Figure 2 The hollow column 14 is located at the lower end of the baffle 17 and is fixedly provided with a cooling pipe 15, and the lower end of the cooling pipe 15 is fixedly connected to the cooling device 19; a wire hole 20 is opened at the center of the lower end of the shell 11; by arranging the cooling pipe 15, the cooling pipe 15 absorbs heat through the hollow column 14, so that the hot flue gas is cooled to the required temperature and then discharged, which can effectively control the output temperature of the flue gas recirculation and prevent the output flue gas from being overheated and affecting the use of the mixed flue gas.
[0020] See also Figure 2 The upper end of the shell 11 is threadedly connected with a water plug 12; the lower end of the shell 11 is threadedly connected with a water plug 21; by arranging the water plug 12 and the water plug 21, the inner side of the shell 11 is easy to clean, thereby ensuring the purity of the output flue gas and preventing the tiny particles in the previous flue gas from interfering with the subsequent flue gas recirculation; by arranging the filter 1 24 and the filter 2 25, the tiny particles mixed in the flue gas and air can be filtered out before entering the inner side of the shell 11 to prevent them from affecting the purity of the output flue gas.
[0021] See also Figure 2A second filter screen 25 is fixedly arranged on the inner side of the smoke pipe 22 , and a first filter screen 24 is fixedly arranged on the inner side of the air inlet pipe 23 .
[0022] During operation, smoke is input from the smoke pipe 22 and filtered through the filter screen 25; air is input from the air inlet pipe 23 and gradually mixed with the smoke after being filtered through the filter screen 1 24; air and smoke can only rise along the spiral steel plate 13 on the inner side of the outer shell 11. During the spiral rise of the smoke and air, the smoke and air are fully mixed under the continuous input pressure and enter the upper end of the hollow column 14 through the vent 16. When the mixed gas of smoke and air gradually increases, the pressure at the lower end of the outlet pipe 26 increases, pushing open the boost block 18, and the smoke is output through the gap between the outlet pipe 26 and the boost block 18 to achieve the recycling of the smoke.
[0023] When fine dust in the flue gas gradually adheres to the spiral steel plate 13 and the inner side of the outer shell 11, in order to improve the mixing efficiency of the flue gas and air, the gas is no longer input from the flue pipe 22 and the air inlet pipe 23; the water plug 12 is opened, and clean liquid is poured into the water plug 12. After the liquid is full, it is allowed to stand for a while, and the water plug 21 is opened to discharge the waste liquid. When the inner side of the outer shell 11 is dry, it is put into use again.
[0024] For example, certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of components as the criteria for distinction. For example, "including" mentioned throughout the specification and claims is an open term, so it should be interpreted as "including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve the technical problem within a certain error range and basically achieve the technical effect.
[0025] It should be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a product or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such product or system. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the product or system including the elements.
[0026] The above description shows and describes several preferred embodiments of the present application, but as mentioned above, it should be understood that the present application is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the application concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not deviate from the spirit and scope of the present application, and should be within the scope of protection of the claims attached to the present application.
Claims
1. A flue gas recirculation device, comprising a bracket (10), a shell (11) is sleeved inside the bracket (10), a flue gas pipe (22) and an air inlet pipe (23) are fixedly arranged at the lower end of the shell (11); a hollow column (14) is fixedly arranged at the center of the inner side of the bracket (10); a pair of vent holes (16) are symmetrically arranged on the upper side of the hollow column (14); a baffle (17) is fixedly arranged on the inner side of the hollow column (14) below the vent holes (16); an air outlet pipe (26) is fixedly arranged at the upper end of the hollow column (14); characterized in that: It also includes a spiral steel plate (13) fixedly arranged on the outer circumference of the hollow column (14); the spiral steel plate (13) is a stainless steel thin plate; the spiral steel plate (13) is fixedly connected to the inner side of the outer shell (11); the upper end of the spiral steel plate (13) is lower than the vent hole (16); and the lower end of the outlet pipe (26) is elastically connected to the boost block (18).
2. A flue gas recirculation device according to claim 1, characterized in that: The hollow column (14) is fixedly provided with a cooling pipe (15) at the lower end of the baffle (17), and the lower end of the cooling pipe (15) is fixedly connected to a cooling device (19); and a wire hole (20) is provided at the center of the lower end of the shell (11).
3. A flue gas recirculation device according to claim 1, characterized in that: The upper end of the shell (11) is threadedly connected to a water plug 1 (12); and the lower end of the shell (11) is threadedly connected to a water plug 2 (21).
4. A flue gas recirculation device according to claim 1, characterized in that: A second filter screen (25) is fixedly arranged on the inner side of the smoke pipe (22), and a first filter screen (24) is fixedly arranged on the inner side of the air intake pipe (23).