Coal mill inlet air duct structure

Abstract

The utility model discloses a coal mill entrance air duct structure relates to coal mill air duct application field, including hot air duct, the side of hot air duct is provided with first cold air duct, the inside mounting of first cold air duct has the turbulence mechanism, and the turbulence mechanism includes turbulence head, and the top of turbulence head is provided as the conical surface, and the recess is seted up in the bottom of turbulence head, and the side of turbulence head is seted up with multiple groups of partial flow groove, and the bottom of turbulence head is provided with mounting bracket, and mounting bracket is connected in the inner wall of first cold air duct. The utility model discloses through with traditional straight -pipe type cold air duct changes for elbow pipe type cold air duct, and can improve the mixing effect of cold air and hot air with turbulence mechanism cooperation, and cold air transports to hot air duct through first cold air duct, when cold air meets turbulence head and is obstructed, and through multiple partial flow grooves diffuses to all around, and hot air also diffuses to all around through the conical surface and contacts with cold air, makes hot air and cold air fully mix, not only can make the flow rate of wind more even also can make the temperature distribution of mixed wind more even.

Description

Technical Field

[0001] This utility model relates to the field of coal mill air duct applications, specifically a coal mill inlet air duct structure. Background Technology

[0002] The coal mill air duct is a dedicated air path system that connects the coal mill to the boiler (or other coal-using equipment). Its core function is to transport hot air to dry raw coal, carry the ground coal powder to the furnace, and control the output of the coal mill and the fineness of the coal powder through air volume regulation.

[0003] Existing coal mill air ducts are usually square air ducts with cold air pipes connected to the sides. The cold air pipes are used to mix cold and hot air to regulate the temperature of the air. It is difficult for cold air to penetrate hot air by its own momentum alone. A long mixing section is required to fill the entire cross section, which results in a very uneven distribution of the primary airflow field at the online measurement section, with obvious high-speed and low-speed zones, as well as obvious high-temperature and low-temperature zones.

[0004] The relative standard deviation of the velocity distribution at the cross-section of the air volume measuring element reached 18.1%, and the relative standard deviation of the temperature distribution was 7.9%. It is urgent to optimize the primary air flow field at the coal mill inlet to solve the problem of extremely uneven flow field distribution in the primary air duct at the coal mill inlet and improve the primary air flow field conditions at the coal mill inlet. Utility Model Content

[0005] Therefore, the purpose of this utility model is to provide a coal mill inlet air duct structure to solve the technical problems mentioned in the background.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a coal mill inlet air duct structure, including a hot air duct, a first cold air duct is provided on the side of the hot air duct, a turbulence mechanism is installed inside the first cold air duct, the turbulence mechanism includes a turbulence head, the top of the turbulence head is set as a conical surface, the bottom of the turbulence head is provided with a groove, and the side of the turbulence head is provided with multiple flow channels, and the bottom of the turbulence head is provided with a mounting bracket, which is connected to the inner wall of the first cold air duct.

[0007] By adopting the above technical solution, the mixing effect of cold and hot air can be improved by changing the traditional straight-pipe cold air duct to a curved-pipe cold air duct and cooperating with a turbulence mechanism. Cold air is delivered to the hot air duct through the first cold air duct, and the direction of cold air delivery is opposite to that of hot air. When the cold air is obstructed by the turbulence head, it diffuses to the surroundings through the multi-component flow channel, while the hot air also diffuses to the surroundings through the conical surface and comes into contact with the cold air, so that the hot air and cold air are fully mixed. This not only makes the airflow velocity more uniform, but also makes the temperature distribution of the mixed air more uniform.

[0008] The present invention is further configured such that the turbulence mechanism is located at the center of the hot air duct.

[0009] Preferably, by placing the turbulence mechanism at the center of the hot air duct, the hot air contact cone surface is more evenly dispersed.

[0010] The present invention is further configured such that the first cold air duct is a right-angle bend, and the bent portion of the first cold air duct is located inside the hot air duct.

[0011] Preferably, by setting the first cold air duct as a bend extending into the hot air duct, the delivery of cold air can be parallel and counter-current to the delivery of hot air.

[0012] The present invention is further configured such that the curved portion of the first cold air duct is parallel to the hot air duct, and the direction of the cold air transported in the first cold air duct is opposite to the direction of the hot air transported in the hot air duct.

[0013] Preferably, by changing the direction of cold air delivery, the cold air can be dispersed by the obstruction and then mixed with the hot air.

[0014] The present invention is further configured such that the interior of the hot air duct is provided with multiple sets of flow equalization plates, and the multiple sets of flow equalization plates are arranged in multiple layers, with the flow equalization plates in each layer being staggered.

[0015] Preferably, staggered flow equalization plates can be used to promote the mixing of hot and cold air.

[0016] The present invention is further configured such that multiple sets of guide plates are provided inside the hot air duct, and the multiple sets of guide plates are distributed at the bends of the hot air duct.

[0017] Preferably, by setting multiple sets of deflectors, the air transported in the curved part of the hot air duct can be guided, so that the air temperature distribution in this area is more uniform.

[0018] The present invention is further configured such that an air volume measuring element is provided inside the hot air duct for measuring the temperature and flow rate of the air.

[0019] Preferably, by incorporating airflow measurement elements, such as temperature sensors and gas flow rate sensors, the temperature and flow rate of the wind can be monitored.

[0020] The present invention is further configured such that a second cold air duct is provided on the side of the hot air duct, an extended straight pipe is provided on the side of the second cold air duct, and two sets of extended bent pipes are provided on the side of the second cold air duct, the two sets of extended bent pipes being distributed on both sides of the extended straight pipe.

[0021] Preferably, by setting up a second cold air duct, an extended straight pipe, and an extended bend pipe, the cold air can be discharged from the outlets in a triangular distribution, thereby improving the mixing effect of cold and hot air.

[0022] The present invention is further configured such that the extended straight pipe is located on one side of the inner wall of the hot air duct, and the two sets of extended curved pipes extend to the other side of the inner wall of the hot air duct, so that the air outlet of one set of extended straight pipes and two sets of extended curved pipes are arranged in a triangular configuration.

[0023] Preferably, by arranging the extended straight pipes and extended curved pipes in a triangular pattern, the mixing effect of hot and cold air can be improved. Furthermore, the two sets of extended curved pipes bend downwards, and after the cold air is delivered, it impacts the inner wall of the hot air duct, allowing more cold air to be delivered downwards and reducing the impact of cold air delivery on the overall air delivery efficiency.

[0024] In summary, the present invention has the following main advantages: This invention improves the mixing effect of cold and hot air by replacing the traditional straight-pipe cold air duct with a curved-pipe cold air duct and combining it with a turbulence mechanism. Cold air is delivered to the hot air duct through the first cold air duct, and the direction of delivery of cold air is opposite to that of hot air. When the cold air is obstructed by the turbulence head, it diffuses to the surroundings through the multi-component flow channels, while the hot air also diffuses to the surroundings through the conical surface and comes into contact with the cold air, so that the hot air and cold air are fully mixed. This not only makes the airflow velocity more uniform, but also makes the temperature distribution of the mixed air more uniform.

[0025] This invention can also promote the mixing effect of cold air and hot air by setting a second cold air duct. The end of the second cold air duct extends into a set of straight extension pipes and two sets of curved extension pipes. The two sets of curved extension pipes are distributed on both sides of the straight extension pipes. The straight extension pipes are located on one side of the inner wall of the hot air duct, while the two sets of curved extension pipes extend to the other side of the inner wall of the hot air duct. The straight extension pipes and the two sets of curved extension pipes deliver cold air sources, which are distributed at three points, allowing for better mixing with hot air. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the internal structure of the hot air duct of this utility model; Figure 3 This is a schematic diagram of the turbulence-disrupting mechanism of this utility model; Figure 4 This is a front view of the distribution of the flow equalization plate of this utility model; Figure 5 This is a schematic diagram showing the distribution of the flow equalization plate and the flow guide plate of this utility model; Figure 6 This is a schematic diagram of the structure of Embodiment 2 of this utility model.

[0027] Explanation of reference numerals in the attached figures: 1. Hot air duct; 2. First cold air duct; 3. Flow equalization plate; 4. Flow guide plate; 5. Flow disturbance mechanism; 501. Flow disturbance head; 502. Conical surface; 503. Flow divider groove; 504. Mounting bracket; 6. Second cold air duct; 7. Extension straight pipe; 8. Extension bend. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0029] The embodiments of this utility model will be described below based on its overall structure.

[0030] Example 1: Please refer to Figures 1-5 A coal mill inlet air duct structure includes a hot air duct 1, a first cold air duct 2 disposed on the side of the hot air duct 1, and a turbulence mechanism 5 installed inside the first cold air duct 2. The turbulence mechanism 5 includes a turbulence head 501, the top of which is a conical surface 502, a groove at the bottom of which is formed, and multiple flow channels 503 formed on the side of which are formed. A mounting bracket 504 is disposed at the bottom of which is connected to the inner wall of the first cold air duct 2. The traditional straight-pipe cold air duct is replaced with a curved-pipe cold air duct, and the combination with the turbulence mechanism 5 can improve the mixing effect of cold air and hot air. Cold air is delivered to hot air duct 1 through the first cold air duct 2, and the direction of cold air delivery is opposite to that of hot air. When the cold air is blocked by the turbulence head 501, it diffuses to the surroundings through the multi-component flow channel 503, while the hot air also diffuses to the surroundings through the conical surface 502 and comes into contact with the cold air, so that the hot air and cold air are fully mixed. This not only makes the airflow speed more uniform, but also makes the temperature distribution of the mixed air more uniform.

[0031] Please refer to the above embodiments for further details. Figure 2 The turbulence mechanism 5 is located at the center of the hot air duct 1. By placing the turbulence mechanism 5 at the center of the hot air duct 1, the hot air contact cone surface 502 is more evenly dispersed.

[0032] Please refer to the above embodiments for further details. Figure 2 The first cold air duct 2 is a right-angle bend, and the bend of the first cold air duct 2 is located inside the hot air duct 1. By setting the first cold air duct 2 as a bend extending into the hot air duct 1, the delivery of cold air can be parallel and counter-current to the delivery of hot air.

[0033] Please refer to the above embodiments for further details. Figure 2The curved part of the first cold air duct 2 is parallel to the hot air duct 1. The direction of the cold air transported in the first cold air duct 2 is opposite to the direction of the hot air transported in the hot air duct 1. By changing the direction of the cold air transport, the cold air can be dispersed by the obstruction and then mixed with the hot air.

[0034] Please refer to the above embodiments for further details. Figure 4 and Figure 5 The hot air duct 1 is equipped with multiple sets of flow equalization plates 3, and the multiple sets of flow equalization plates 3 are arranged in multiple layers. The flow equalization plates 3 in each layer are staggered. By setting the staggered flow equalization plates 3, the mixing of hot and cold air can be promoted.

[0035] Please refer to the above embodiments for further details. Figure 2 The hot air duct 1 is equipped with multiple sets of guide plates 4. These guide plates 4 are distributed at the bends of the hot air duct 1. By setting multiple sets of guide plates 4, the air transported by the hot air duct 1 in the bends can be guided, making the air temperature distribution in this area more uniform.

[0036] Please refer to the above embodiments for further details. Figure 1 The hot air duct 1 is equipped with an air volume measuring element to measure the temperature and flow rate of the air. By setting the air volume measuring element, such as a temperature sensor and a gas flow rate sensor, the temperature and flow rate of the air can be monitored.

[0037] Example 2: Please refer to Figure 6 A coal mill inlet air duct structure includes a second cold air duct 6 on the side of a hot air duct 1, an extended straight pipe 7 on the side of the second cold air duct 6, and two sets of extended bends 8 on the side of the second cold air duct 6. The two sets of extended bends 8 are distributed on both sides of the extended straight pipe 7. The extended straight pipe 7 is located on one side of the inner wall of the hot air duct 1, and the two sets of extended bends 8 extend to the other side of the inner wall of the hot air duct 1, so that the air outlets of one set of extended straight pipe 7 and two sets of extended bends 8 are arranged in a triangle. By setting the second cold air duct 6, the extended straight pipe 7 and the extended bends 8, cold air can be discharged from the triangularly distributed air outlets, thereby improving the mixing effect of hot and cold air.

[0038] In practical operation, for Example 1: Hot air is delivered from top to bottom through hot air duct 1. When the temperature of the delivered hot air needs to be adjusted, cold air is delivered into the interior of the first cold air duct 2. The cold air moves along the first cold air duct 2 and impacts the bottom of the turbulence head 501, thereby spreading to the surroundings through the multi-component flow channel 503. The turbulence head 501 is used to reduce the flow rate of the cold air, while the hot air spreads to the surroundings through the conical surface 502. Thus, the hot air and cold air are fully mixed. Due to the large volume of hot air, the hot and cold air continue to flow along the hot air duct 1 after mixing and pass through the flow equalization plate 3 and the flow guide plate 4. The flow equalization plate 3 and the flow guide plate 4 can further promote the mixing of hot and cold air.

[0039] For Example 2: Cold air is delivered into hot air duct 1 through the extended straight pipe 7 and extended bent pipe 8 on the side of the second cold air duct 6. Since the extended straight pipe 7 and the two sets of extended bent pipes 8 are triangularly distributed, the cold air is more evenly distributed when it enters the hot air duct 1, so that the hot air can mix better with the cold air. The traditional cold air duct is only located on one side of the inner wall of the hot air duct 1, which causes the cold air to concentrate on one side of the inner wall of the hot air duct 1 for a long distance, resulting in poor mixing effect of cold and hot air.

[0040] Although embodiments of the present invention have been shown and described, these specific embodiments are merely explanations of the present invention and are not intended to limit the invention. The specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. After reading this specification, those skilled in the art may make modifications, substitutions, and variations to the embodiments as needed without departing from the principles and spirit of the present invention, provided that such modifications, substitutions, and variations are within the scope of the claims of the present invention and are protected by patent law.

Claims

1. A coal mill inlet air duct structure, comprising a hot air duct (1), characterized in that: The hot air duct (1) is provided with a first cold air duct (2) on its side. The first cold air duct (2) is equipped with a turbulence mechanism (5). The turbulence mechanism (5) includes a turbulence head (501), and the top of the turbulence head (501) is set as a conical surface (502). The bottom of the turbulence head (501) is provided with a groove, and the side of the turbulence head (501) is provided with multiple flow channels (503). The bottom of the turbulence head (501) is provided with a mounting bracket (504), and the mounting bracket (504) is connected to the inner wall of the first cold air duct (2).

2. The structure of the coal mill inlet air duct according to claim 1, characterized in that: The turbulence mechanism (5) is located at the center of the hot air duct (1).

3. The structure of the coal mill inlet air duct according to claim 2, characterized in that: The first cold air duct (2) is a right-angle bend, and the bent part of the first cold air duct (2) is located inside the hot air duct (1).

4. The structure of the coal mill inlet air duct according to claim 3, characterized in that: The curved portion of the first cold air duct (2) is parallel to the hot air duct (1), and the direction of the cold air transported in the first cold air duct (2) is opposite to the direction of the hot air transported in the hot air duct (1).

5. The structure of the coal mill inlet air duct according to claim 4, characterized in that: The hot air duct (1) is provided with multiple sets of flow equalization plates (3), and the multiple sets of flow equalization plates (3) are arranged in multiple layers, with the flow equalization plates (3) of each layer being arranged in an alternating manner.

6. The structure of the coal mill inlet air duct according to claim 5, characterized in that: The hot air duct (1) is provided with multiple sets of guide plates (4), which are distributed at the bends of the hot air duct (1).

7. The structure of the coal mill inlet air duct according to claim 6, characterized in that: The hot air duct (1) is equipped with an air volume measuring element for measuring the temperature and flow rate of the air.

8. The structure of the coal mill inlet air duct according to claim 1, characterized in that: The hot air duct (1) is provided with a second cold air duct (6) on its side. The side of the second cold air duct (6) is provided with an extension straight pipe (7), and the side of the second cold air duct (6) is provided with two sets of extension bends (8). The two sets of extension bends (8) are distributed on both sides of the extension straight pipe (7).

9. The structure of the coal mill inlet air duct according to claim 8, characterized in that: The extended straight pipe (7) is located on one side of the inner wall of the hot air duct (1), and two sets of extended bend pipes (8) extend to the other side of the inner wall of the hot air duct (1), so that the air outlets of one set of extended straight pipes (7) and two sets of extended bend pipes (8) are arranged in a triangular configuration.

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