Natural gas combustion flue gas fog and white elimination device
By combining external and internal dual cooling components with a steam trap and a guide cotton rope design, the problem of white smoke caused by a sudden drop in flue gas temperature was solved, achieving efficient cooling and dehumidification, and reducing water consumption and disposal costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-19
- Publication Date
- 2026-04-14
AI Technical Summary
Existing methods for eliminating white smoke from flue gas, such as condensation, suffer from high water consumption and treatment costs, making it difficult to effectively address the white smoke phenomenon caused by a sudden drop in flue gas temperature.
It adopts a dual cooling component with external and internal cooling, including a spiral outer cooling channel and an inner cooling channel, combined with a steam trap and a steam guide. It uses external air to cool the flue gas in two ways, and uses a steam trap and a steam guide cotton rope to capture and evaporate the moisture in the flue gas, thereby reducing humidity.
It effectively reduces flue gas temperature and humidity, eliminates white smoke in flue gas, and reduces water consumption and disposal costs.
Smart Images
Figure CN121854881A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of flue gas treatment technology, specifically to a device for eliminating fog and white spots in natural gas combustion flue gas. Background Technology
[0002] Natural gas, as a clean and efficient fossil fuel, is widely used in industrial production processes such as lead and zinc smelting. Its main component, methane (CH4), produces a large amount of water vapor (H2O), carbon dioxide (CO2), and a small amount of nitrogen oxides (NOx) when burned. In actual production, the high-temperature and high-humidity combustion flue gas, after being discharged from the chimney, mixes rapidly with the cooler ambient air, causing the flue gas temperature to drop sharply below the dew point temperature. At this time, the water vapor in the flue gas condenses into countless tiny droplets. These droplets scatter light, forming the visually apparent "white smoke" (i.e., "wet plume").
[0003] Traditional methods for eliminating white smoke in flue gas mainly include heating, condensation, condensation and reheating, solution absorption, and electrostatic precipitator methods. Among these, condensation has received widespread attention due to its cost-effectiveness in eliminating white smoke. Condensation can be further divided into indirect and direct condensation. Direct condensation typically uses a specialized fine mist spray gun to spray and cool the flue gas, causing water vapor to condense rapidly. Indirect condensation, on the other hand, utilizes demineralized water flowing within heat exchange tubes to cool and condense the flue gas. While both methods are effective in eliminating white smoke, they both require low water supply temperatures and large amounts of circulating water, which undoubtedly increases water consumption and disposal costs. Summary of the Invention
[0004] The main objective of this invention is to provide a device for eliminating fog and whitening of natural gas combustion flue gas, which solves the problem of visually "white smoke" formed when the flue gas temperature drops sharply below the dew point temperature.
[0005] To achieve the above objectives, the present invention provides a natural gas combustion flue gas defogging and whitening device, comprising: The external cooling assembly includes an outer cooling channel arranged in a spiral shape on the outer wall of the main pipe and an induced draft fan connected to the outer cooling channel; the external flue pipe is connected to the bottom end of the main pipe. The internal cooling assembly includes multiple sets of inner cooling elements spaced apart from top to bottom within the main duct, and multiple sets of steam traps mounted on the inner cooling elements. Each inner cooling element has an inner cooling channel. Each inner cooling channel has a steam guide element communicating with the steam trap. The main duct has an exhaust element communicating with the inner cooling channel. The inner cooling elements are connected to an induced draft fan. Under the action of the induced draft fan, external air enters the outer and inner cooling channels from top to bottom, thereby cooling the flue gas entering the main duct from both the outside and inside, from bottom to top.
[0006] As a further improvement of the present invention, the outer wall of the main pipe is provided with spiral cooling fins; the end of the cooling fins away from the main pipe is provided with a closed tube, and the spacing between the cooling fins forms an outer cooling channel.
[0007] As a further improvement of the present invention, the inner cooling component includes multiple sets of detachable inner cooling rings disposed in the main pipe and multiple sets of inner cooling pipes staggered in the inner cooling rings; the interior of the inner cooling rings and the interior of the inner cooling pipes are connected to form an inner cooling channel.
[0008] As a further improvement of the present invention, a gap is left between the inner cooling pipes to form a smoke passage; the center of the inner cooling ring is provided with a collecting cylinder that communicates with the inner cooling pipes.
[0009] As a further improvement of the present invention, it also includes a connecting pipe; the two ends of the connecting pipe are respectively connected to two adjacent sets of collecting cylinders from top to bottom.
[0010] As a further improvement of the present invention, the inner cooling ring is provided with an air inlet pipe that penetrates the main pipe; the air inlet pipe is connected to the induced draft fan; the exhaust component includes an exhaust pipe connected to the inner cooling channel and a water storage tank connected to the exhaust pipe.
[0011] As a further improvement of the present invention, the adjacent inner cooling pipes are staggered in the vertical direction so that the adjacent inner cooling pipes are located directly above the smoke passage in the vertical direction, separating the smoke passage.
[0012] As a further improvement of the present invention, the steam trapping component includes multiple sets of steam trapping nets disposed on the inner cooling pipe; the air guiding component includes an air guiding cotton rope disposed in the inner cooling channel; one end of the air guiding cotton rope passes through the inner cooling pipe and is located inside the steam trapping net.
[0013] The beneficial effects of this invention are reflected in: The flue gas in the main duct is cooled by air flowing downwards through both the outer and inner cooling channels. This causes the temperature of the flue gas in the main duct to decrease from bottom to top. Under the action of the steam trap, the moisture in the flue gas is captured and discharged from the main duct for collection, reducing the humidity of the flue gas. When the moisture in the steam trap is discharged from the main duct, it evaporates the moisture in the air guide through heat exchange with the flue gas. During the evaporation process, the temperature of the flue gas is consumed again. The moisture in the flue gas is discharged by the flue gas itself combined with the air flowing in the inner cooling channel, reducing the humidity of the flue gas. Thus, the flue gas is discharged after being cooled and dehumidified, eliminating the "wet plume" formed after the flue gas is discharged. Attached Figure Description
[0014] Figure 1 This is an overall schematic diagram of a natural gas combustion flue gas defogging and whitening device according to the present invention; Figure 2 This is a schematic diagram of the internal structure of a natural gas combustion flue gas defogging and whitening device according to the present invention; Figure 3 This is a schematic diagram of the inner cooling component of a natural gas combustion flue gas defogging and whitening device according to the present invention; Figure 4 This is a schematic diagram of the exhaust component structure of a natural gas combustion flue gas defogging and whitening device according to the present invention; Explanation of reference numerals in the attached figures: 1. Main pipe; 2. Outer cooling channel; 3. Exhaust fan; 4. External flue gas pipe; 5. Inner cooling components; 501. Inner cooling ring; 502. Inner cooling pipe; 6. Steam trap; 601. Steam trap net; 7. Inner cooling channel; 8. Steam guide; 9. Steam exhaust; 901. Exhaust pipe; 902. Water storage tank; 10. Cooling fins; 11. Sealing pipe; 12. Graphite sealing gasket; 13. Exhaust pipe; 14. Flue gas passage; 15. Collecting cylinder; 16. Connecting pipe; 17. Inlet pipe; 18. Fixed pipe. Detailed Implementation
[0015] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the described embodiments are merely some, not all, of the embodiments of this invention. Unless otherwise specified, the embodiments and features described in this application can be combined with each other. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.
[0016] In one embodiment, see Figure 1 , 2 The present invention provides a natural gas combustion flue gas defogging and dewhitening device, comprising a main pipeline 1, an external cooling component, and an internal cooling component.
[0017] The external cooling assembly includes an outer cooling channel 2 spirally arranged on the outer wall of the main pipe 1, an induced draft fan 3 connected to the outer cooling channel 2, and an external flue gas pipe 4 connected to the bottom end of the main pipe 1. The internal cooling assembly includes multiple sets of inner cooling elements 5 spaced from top to bottom in the main pipe 1, multiple sets of steam trapping elements 6 arranged on the inner cooling elements 5, an inner cooling channel 7 in the inner cooling element 5, a steam guide element 8 connected to the steam trapping element 6 in the inner cooling channel 7, and an exhaust element 9 connected to the inner cooling channel 7 outside the main pipe 1. The inner cooling element 5 is connected to the induced draft fan 3. Under the action of the induced draft fan 3, the external air enters the outer cooling channel 2 and the inner cooling channel 7 from top to bottom, thereby cooling the flue gas entering the main pipe 1 from the outside and inside of the main pipe 1 from bottom to top.
[0018] Further, see Figure 1 , 2 The outer wall of the main pipe 1 is provided with a spiral cooling fin 10. The end of the cooling fin 10 away from the main pipe 1 is provided with a closed pipe 11. The spacing between the cooling fins 10 forms an outer cooling channel 2.
[0019] Preferably, the cooling fin 10 is welded to the outer wall of the main pipe 1, and a graphite sealing gasket 12 is provided at the end of the cooling fin 10. The sealing pipe 11 is fitted on the graphite sealing gasket 12, so that the cooling fin 10 and the sealing pipe 11 are sealed.
[0020] Preferably, the induced draft fan 3 uses existing equipment. The induced draft fan 3 is equipped with an air intake pipe 13, which is connected to the top of the outer cooling channel 2. Under the action of the induced draft fan 3, external air enters from the top of the outer cooling channel 2. As the external air enters the outer cooling channel 2, it contacts the cooling fins 10 and the outer wall of the main pipe 1 and undergoes heat exchange. The temperature of the external air entering the outer cooling channel 2 is relatively low. As the external air moves down along the outer cooling channel 2, the residence time of the external air in the outer cooling channel 2 increases. As the external air moves down, the flue gas located at the top of the main pipe 1 is always in heat exchange with the newly entered, lower-temperature external air, thereby reducing the temperature of the flue gas in the main pipe 1 from bottom to top, achieving a primary cooling of the flue gas in the main pipe 1.
[0021] Further, see Figure 2 , 3 The inner cooling component 5 includes multiple sets of detachable inner cooling rings 501 installed in the main pipe 1 and multiple sets of inner cooling pipes 502 interlaced in the inner cooling rings 501. The interior of the inner cooling rings 501 and the interior of the inner cooling pipes 502 are connected to form an inner cooling channel 7.
[0022] Preferably, the inner cooling ring 501 is installed on the inner wall of the main pipe 1 by means of clamps and bolts.
[0023] Further, see Figure 2 , 3 A gap is left between the inner cooling pipes 502 to form a smoke passage 14, and a collecting cylinder 15 connected to the inner cooling pipes 502 is provided at the center of the inner cooling ring 501.
[0024] Preferably, the inner cooling ring 501 has multiple sets of through holes, the outer wall of the collecting cylinder 15 has a connecting hole, one end of the inner cooling pipe 502 is welded to the through hole, and the other end is welded to the connecting hole.
[0025] Further, see Figure 2 , 3It also includes a connecting pipe 16, the two ends of which are connected to two adjacent sets of collecting cylinders 15 from top to bottom.
[0026] Preferably, the connecting pipe 16 is located at the center of the main pipe 1, and the connecting pipe 16 is welded to the collecting pipe.
[0027] Further, see Figure 2 , 3 The inner cooling ring 501 is provided with an air inlet pipe 17 that passes through the main pipe 1 and is connected to the induced draft fan 3; the exhaust components include an exhaust pipe 901 that is connected to the inner cooling channel 7 and a water storage tank 902 that is connected to the exhaust pipe 901.
[0028] Preferably, the intake pipe 17 is connected to the inner cooling pipe 502 located at the highest position, and the intake pipe 17 is connected to the exhaust pipe 13. Under the action of the exhaust fan 3, the outside air enters the inner cooling ring 501 located at the highest position along the intake pipe 17 and moves along the inner cooling pipe 502. It then enters the lower inner cooling ring 501 and inner cooling pipe 502 through the connecting pipe 16, and is finally discharged from the exhaust pipe 901. After the outside air enters the inner cooling ring 501 and inner cooling pipe 502, it exchanges heat with the flue gas in the main pipe 1. The outside air moves down the main pipe 1 from top to bottom, and just as it enters... The external air temperature inside the outer cooling channel 2 is relatively low. As the external air moves downward along the outer cooling channel 2, the residence time of the external air inside the outer cooling channel 2 increases, which can increase the heat exchange time and improve the heat exchange efficiency. As the external air moves downward, the flue gas located at the top of the main pipe 1 is always exchanging heat with the newly entered, lower-temperature external air, thereby causing the temperature of the flue gas in the main pipe 1 to decrease from bottom to top, achieving secondary cooling of the flue gas in the main pipe 1. Combined with the outer cooling channel 2 outside the main pipe 1, the flue gas in the main pipe 1 can be cooled twice, improving the cooling effect.
[0029] Further, see Figure 2 , 3 The adjacent inner cooling pipes 502 are staggered in the vertical direction so that the adjacent inner cooling pipes 502 are located directly above the smoke passage 14 in the vertical direction, separating the smoke passage 14.
[0030] Preferably, the inner cooling pipes 502 are arranged in three layers from top to bottom. The inner cooling pipes 502 in the middle layer are staggered with the inner cooling pipes 502 in the upper and lower layers in the vertical direction, thereby dividing the flue gas passage 14 in the vertical direction. As the flue gas moves upward along the lower flue gas passage 14, the upward flue gas is directly facing the inner cooling pipes 502 in the middle layer. This increases the contact time between the flue gas and the inner cooling pipes 502, while the inner cooling pipes 502 divide and change the direction of the flue gas. The divided flue gas moves upward along the middle flue gas passage 14 and contacts the inner cooling pipes 502 in the upper layer, and is divided and changed direction again. The flue gas is divided and changed direction multiple times, increasing the contact time with the inner cooling pipes 502, thereby improving the heat exchange efficiency.
[0031] Further, see Figure 3 , 4 The steam trapping component 6 includes multiple sets of steam trapping nets 601 installed on the inner cooling pipe 502, and the air guiding component includes an air guiding cotton rope installed in the inner cooling channel 7, with one end of the air guiding cotton rope passing through the inner cooling pipe 502 and located inside the steam trapping net 601.
[0032] Preferably, the steam trap 601 is an emery eliminator, with guide cotton ropes distributed inside the emery eliminator. A fixed pipe 18, connected to the inner cooling channel 7, is provided on the inner cooling pipe 502. The guide cotton ropes pass through the fixed pipe 18 and are located within the inner cooling channel 7. The steam trap is installed at the end of the fixed pipe 18. As the flue gas moves upward along the main pipe 1, the steam trap 601 captures moisture in the flue gas, reducing its moisture content. The moisture on the steam trap 601 enters the guide cotton ropes and flows along them into the inner cooling channel 7, where it interacts with the flue gas inside the inner cooling pipe 502. Upon contact, the temperature of the inner cooling pipe 502 rises, causing the moisture on the air-guiding cotton rope located in the inner cooling channel 7 to evaporate. This moisture is then carried by the external air in the inner cooling channel 7 and flows out along the exhaust pipe 901 into the water storage tank 902. The water storage tank 902 is equipped with a discharge pipe for discharging air. As the moisture on the air-guiding cotton rope located in the inner cooling channel 7 evaporates, the moisture in the air-guiding cotton rope located in the steam trap 601 can be introduced into the inner cooling channel 7, thereby continuously capturing and discharging the moisture in the flue gas in the main pipe 1, reducing the humidity of the flue gas.
[0033] In this embodiment, the flue gas in the main pipe 1 is cooled by air flowing from top to bottom in the outer cooling channel 2 and the inner cooling channel 7. This causes the temperature of the flue gas in the main pipe 1 to decrease from bottom to top. Under the action of the steam trap 601, the moisture in the flue gas is captured and discharged from the main pipe 1 for collection, reducing the humidity of the flue gas. When the moisture in the steam trap 601 is discharged from the main pipe 1, the moisture in the air guide cotton rope is evaporated by heat exchange with the flue gas. During the evaporation process, the temperature of the flue gas is consumed again. The moisture in the flue gas is discharged by the flue gas itself combined with the air flowing in the inner cooling channel 7, reducing the humidity of the flue gas. Thus, the flue gas is discharged after being cooled and dehumidified, eliminating the "wet plume" formed after the flue gas is discharged.
[0034] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A device for eliminating fog and white mist in natural gas combustion flue gas, characterized in that, include: The external cooling assembly includes an outer cooling channel (2) spirally arranged on the outer wall of the main pipe (1) and an induced draft fan (3) connected to the outer cooling channel (2); the external flue gas pipe (4) is connected to the bottom end of the main pipe (1); The internal cooling assembly includes multiple sets of internal cooling elements (5) spaced from top to bottom within the main pipe (1) and multiple sets of steam trapping elements (6) on the internal cooling elements (5); the internal cooling elements (5) are provided with internal cooling channels (7); the internal cooling channels (7) are provided with steam guide elements (8) communicating with the steam trapping elements (6); the main pipe (1) is provided with exhaust elements (9) communicating with the internal cooling channels (7); the internal cooling elements (5) are connected to the induced draft fan (3); the external air enters the external cooling channels (2) and the internal cooling channels (7) from top to bottom under the action of the induced draft fan (3), thereby cooling the flue gas entering the main pipe (1) from the outside and inside of the main pipe (1) from bottom to top.
2. The natural gas combustion flue gas defogging and whitening device according to claim 1, characterized in that: The outer wall of the main pipe (1) is provided with spiral cooling fins (10); the end of the cooling fins (10) away from the main pipe (1) is provided with a closed tube (11), and the spacing between the cooling fins (10) forms an outer cooling channel (2).
3. The natural gas combustion flue gas defogging and whitening device according to claim 2, characterized in that: The inner cooling component (5) includes multiple sets of detachable inner cooling rings (501) installed in the main pipe (1) and multiple sets of inner cooling pipes (502) staggered in the inner cooling rings (501); the inner cooling rings (501) are connected to the inner cooling pipes (502) to form an inner cooling channel (7).
4. The natural gas combustion flue gas defogging and whitening device according to claim 3, characterized in that: The gaps between the inner cooling pipes (502) form a smoke passage (14); the center of the inner cooling ring (501) is provided with a collecting cylinder (15) that communicates with the inner cooling pipes (502).
5. The natural gas combustion flue gas defogging and whitening device according to claim 4, characterized in that: It also includes a connecting pipe (16); the two ends of the connecting pipe (16) are respectively connected to two adjacent sets of collecting cylinders (15) from top to bottom.
6. The natural gas combustion flue gas defogging and whitening device according to claim 5, characterized in that: The inner cooling ring (501) is provided with an air inlet pipe (17) that passes through the main pipe (1); the air inlet pipe (17) is connected to the induced draft fan (3); the exhaust components include an exhaust pipe (901) connected to the inner cooling channel (7) and a water storage tank (902) connected to the exhaust pipe (901).
7. The natural gas combustion flue gas defogging and whitening device according to claim 6, characterized in that: The adjacent inner cooling pipes (502) are staggered in the vertical direction so that the adjacent inner cooling pipes (502) are located directly above the smoke passage (14) in the vertical direction, separating the smoke passage (14).
8. The natural gas combustion flue gas defogging and whitening device according to claim 7, characterized in that: The steam trapping component (6) includes multiple sets of steam trapping nets (601) installed on the inner cooling pipe (502); the air guiding component includes an air guiding cotton rope installed in the inner cooling channel (7); one end of the air guiding cotton rope passes through the inner cooling pipe (502) and is located inside the steam trapping net (601).