Air distribution device for fluidized bed

Abstract

The utility model provides an air distribution device for a fluidized bed. The air distribution device comprises a hearth; the main air pipe extends in the height direction, penetrates through the bottom of the hearth and is suitable for receiving external airflow; the air bellow is mounted in the hearth and is communicated with the tail end of the main air pipe; the branch air pipes are evenly arranged on the side wall of the air bellow in the circumferential direction and communicate with the interior of the air bellow, part of the pipe section, close to the tail end, of each branch air pipe extends upwards in the height direction, and at least one air cap extending upwards in the height direction is installed near the tail end of each branch air pipe; and uniformly distributed airflow is formed in the hearth.

Description

Technical Field

[0001] At least one embodiment of this utility model relates to the technical field of air distribution equipment for fluidized beds, and particularly to an air distribution device for fluidized beds. Background Technology

[0002] Fluidized beds are widely used industrial devices primarily for gas-solid reactions, offering advantages such as simple structure, no moving parts, and uniform gas-solid mixing. The air distribution system is a key component of a fluidized bed; its function is to allow external gas to pass evenly through the bottom of the furnace and enter the furnace interior, providing the necessary conditions for the fluidization of solids within the furnace.

[0003] Existing air distribution devices mainly adopt two types of structures: air distribution plate structure and air distribution duct structure.

[0004] An air distribution device with an air distribution plate structure includes an air distribution plate with an air cap, an air chamber below the air distribution plate, and a slag discharge port formed on the air distribution plate and passing through the air chamber. To prevent the air distribution plate from deforming due to heat, it is usually necessary to water cool it to avoid expansion deformation caused by high temperatures. However, this type of air distribution device is suitable for furnaces with existing water cooling systems. When the furnace is insulated, a water cooling device must be specially installed for the air distribution plate, making the system more cumbersome. Furthermore, the thermal expansion difference between the water-cooled air distribution plate and the insulated furnace makes the expansion and sealing structure of the device more complex.

[0005] To overcome the aforementioned technical defects of air distribution devices with air distribution plate structures, existing technology provides an air distribution device with an air distribution duct structure. The duct and air caps are made of heat-resistant alloy steel. The outer wall of the main air duct is perforated, leading to several branch air ducts. These branch air ducts are deflected by elbows, and several air caps are arranged on each branch air duct. However, in this existing air distribution device with an air distribution duct structure, when the furnace cross-section is large, the number of air caps is limited by the diameter of the main air duct and cannot be increased proportionally. This results in larger air cap sizes, increased spacing between air caps, and reduced air distribution uniformity. Utility Model Content

[0006] In view of this, the present invention provides an air distribution device for a fluidized bed to form a uniformly distributed airflow inside the furnace.

[0007] According to an embodiment of the present invention, an air distribution device for a fluidized bed is provided, comprising: a furnace; a main air duct extending along the height direction and passing through the bottom of the furnace for receiving external airflow; an air box installed inside the furnace and connected to the end of the main air duct; and a plurality of branch air ducts evenly arranged on the side wall of the air box in the circumferential direction and respectively connected to the interior of the air box, wherein a portion of each branch air duct near its tail extends upward along the height direction and at least one air cap extending upward along the height direction is installed near the tail end of each branch air duct to form a uniformly distributed airflow inside the furnace.

[0008] According to an embodiment of the present invention, the branch duct is constructed as a generally L-shaped bend, with one end connected to the side wall of the air box and the other end extending toward the space above the furnace.

[0009] According to an embodiment of the present invention, the number of branch air pipes arranged along the circumferential direction on the side wall of the wind box is even, and the multiple branch air pipes are symmetrically arranged about the radial extension line of the cross-section of the furnace.

[0010] According to an embodiment of the present invention, a plurality of first ventilation holes are evenly arranged in the circumferential direction on the side wall of each branch duct extending toward the upper space of the furnace, and a wind cap extending upward in the height direction is installed on each first ventilation hole.

[0011] According to an embodiment of the present invention, a second vent hole is provided at the center of the top of each branch duct, and a wind cap extending upward along the height direction is installed on the second vent hole.

[0012] According to an embodiment of the present invention, a plurality of third vent holes are evenly arranged on the top of the bellows, and a wind cap extending upward along the height direction is installed on each of the third vent holes.

[0013] According to an embodiment of the present invention, the wind caps installed on the first vent, the second vent, and the third vent are coplanar on one side facing the upper space of the furnace.

[0014] According to an embodiment of the present invention, the bellows is constructed as a cylindrical body with a roughly circular cross-section, so that the amount of expansion extending in the circumferential direction during the process of heating and expansion of the bellows is uniform.

[0015] According to an embodiment of the present invention, two slag discharge pipes extending downward along the height direction are provided at the bottom of the furnace. The two slag discharge pipes are symmetrically arranged about the axis of the furnace. Each slag discharge pipe is located outside the wind box and the branch air pipe, so that the thermal expansion of the slag discharge pipe is independent of the wind box and the branch air pipe.

[0016] According to an embodiment of the present invention, refractory material is arranged inside the furnace to encapsulate a portion of the main air duct, the wind box, the branch air duct, and the slag discharge pipe located inside the furnace.

[0017] According to the above embodiments of the present invention, the air distribution device for a fluidized bed has a main air duct extending along the height direction inserted into the bottom of the furnace to receive external airflow. A wind box is installed inside the furnace and connected to the end of the main air duct. Multiple branch air ducts are evenly arranged circumferentially on the side wall of the wind box and connected to the interior of the wind box. A section of each branch air duct near its tail extends upwards along the height direction, and at least one wind cap extending upwards along the height direction is installed near the tail end of each branch air duct to form a uniform airflow inside the furnace. Attached Figure Description

[0018] Figure 1 This is a front view of an air distribution device for a fluidized bed according to an embodiment of the present invention;

[0019] Figure 2 This is a top view of an air distribution device for a fluidized bed according to an embodiment of the present invention; and

[0020] Figure 3 This is a schematic diagram showing the installation relationship between the air box, main air duct, branch air duct, and slag discharge pipe of the air distribution device for a fluidized bed according to an embodiment of this utility model.

[0021] In the picture:

[0022] 1-Furnace chamber;

[0023] 2-Main air duct;

[0024] 3-Blowbox; 31-Third vent;

[0025] 4-Branch duct; 41-First vent; 42-Second vent;

[0026] 5-Hood;

[0027] 6-Refractory materials;

[0028] 7-Slag discharge pipe. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0030] According to one aspect of the inventive concept of this utility model, an air distribution device for a fluidized bed is provided, comprising: a furnace; a main air duct extending along the height direction and passing through the bottom of the furnace for receiving external airflow; a wind box installed inside the furnace and connected to the end of the main air duct; and a plurality of branch air ducts evenly arranged on the side wall of the wind box in the circumferential direction and connected to the inside of the wind box respectively, wherein a portion of each branch air duct near its tail extends upward along the height direction and at least one wind cap extending upward along the height direction is installed near the tail end of each branch air duct to form a uniformly distributed airflow inside the furnace.

[0031] Figure 1 This is a front view of an air distribution device for a fluidized bed according to an embodiment of the present invention; Figure 2 This is a top view of an air distribution device for a fluidized bed according to an embodiment of the present invention.

[0032] According to an exemplary embodiment of the present invention, please refer to Figures 1-2 A fluidized bed air distribution device is provided, comprising a furnace 1, a main air duct 2, an air box 3, and multiple branch air ducts 4. The main air duct 2 extends along the height direction and passes through the bottom of the furnace 1, suitable for receiving external airflow. The air box 3 is installed inside the furnace 1 and communicates with the end of the main air duct 2. Multiple branch air ducts 4 are evenly arranged on the side wall of the air box 3 along the circumferential direction and communicate with the interior of the air box 3 respectively. A section of each branch air duct 4 near its tail extends upward along the height direction, and at least one air cap 5 extending upward along the height direction is installed near the tail end of each branch air duct 4 to form a uniformly distributed airflow inside the furnace 1.

[0033] In this embodiment, the main air duct 2, extending along the height direction, passes through the bottom of the furnace 1 to receive external airflow. The bellows 3 is installed inside the furnace 1 and communicates with the end of the main air duct 2. Multiple branch air ducts 4 are evenly arranged on the side wall of the bellows 3 along the circumferential direction and communicate with the inside of the bellows 3 respectively. A section of each branch air duct 4 near its tail extends upward along the height direction, and at least one wind cap 5 extending upward along the height direction is installed near the tail end of each branch air duct 4 to form a uniformly distributed airflow inside the furnace 1.

[0034] It should be noted that, in this embodiment, the furnace chamber 1 is an insulated furnace chamber, constructed of wear-resistant and refractory materials. A through hole is provided at the center of the bottom of the furnace chamber 1 to allow one end of the main air duct 2 to extend into the interior of the furnace chamber 1 through the through hole.

[0035] Furthermore, the material of the main air duct 2 is selected based on the physicochemical properties and temperature of the airflow entering the furnace 1, and it is used to guide the external airflow into the furnace 1. The main air duct 2 is set as a pipe with a roughly circular cross-section. The branch air duct 4 is a pipe with a roughly circular cross-section. When heated, the main air duct 2 and the branch air duct 4 can expand freely upward in the axial direction without restriction.

[0036] In some exemplary embodiments, reference is made to Figure 1 The branch duct 4 is constructed as an approximately L-shaped bend, with one end connected to the side wall of the bellows 3 and the other end extending toward the space above the furnace 1.

[0037] In this embodiment, multiple branch ducts 4 are evenly arranged on the side wall of the bellows 3 in the circumferential direction. Each branch duct 4 is constructed as an approximately L-shaped bend, with one end connected to the side wall of the bellows 3 and the other end extending towards the space above the furnace 1. That is, one end of the branch duct 4 communicates with the interior of the bellows 3 and bends towards the space above the furnace 1, so that the airflow inside the bellows 3 is blown into the interior of the furnace 1 through the branch duct 4. The air distribution device of this embodiment uses branch ducts 4 for air distribution, which effectively supplements the air distribution in areas not covered by the air distribution range of the bellows 3 inside the furnace 1.

[0038] In some exemplary embodiments, reference is made to Figures 1-2 The number of branch air pipes 4 arranged along the circumferential direction on the side wall of the wind box 3 is even, and the multiple branch air pipes 4 are symmetrically arranged about the radial extension line of the cross section of the furnace 1.

[0039] With the above arrangement, multiple branch air ducts 4 are evenly arranged on the side wall of the wind box 3 in the circumferential direction, so that part of the airflow inside the wind box 3 flows evenly into the furnace 1 through the multiple branch air ducts 4. For example, in this embodiment, the number of branch air ducts 4 arranged on the side wall of the wind box 3 in the circumferential direction is 8.

[0040] In some exemplary embodiments, reference is made to Figures 1-2 Each branch duct 4 has multiple first ventilation holes 41 evenly arranged in the circumferential direction on the side wall of the portion extending towards the upper space of the furnace 1, and each first ventilation hole 41 is equipped with a wind cap 5 extending upward in the height direction.

[0041] The above-mentioned configuration guides the airflow from the first vent 41 into the interior of the furnace 1.

[0042] In some exemplary embodiments, reference is made to Figures 1-2 Each branch duct 4 is also provided with a second vent 42 at the top center, and a vent cap 5 extending upward along the height direction is installed on the second vent 42.

[0043] The above-mentioned configuration guides the airflow from the second vent 42 into the interior of the furnace 1.

[0044] In some exemplary embodiments, reference is made to Figures 1-2 The top of the bellows 3 is evenly provided with multiple third vent holes 31, and each third vent hole 31 is equipped with a wind cap 5 that extends upward along the height direction.

[0045] In this embodiment, by uniformly arranging a plurality of third ventilation holes 31 on the top of the wind box 3, and installing a wind cap 5 extending upward along the height direction on each third ventilation hole 31, the airflow passes through the wind cap 5 and flows from the wind box 3 into the interior of the furnace 1.

[0046] Furthermore, through the above-mentioned arrangement, the number of wind caps 5 set on the top of the wind box 3 can be flexibly changed, so that the number of wind caps 5 is not restricted by the diameter and structure of the branch air pipe 4, and the spacing between wind caps 5 and the size of wind caps 5 can be designed more reasonably to improve the uniformity of air distribution.

[0047] It should be noted that in this embodiment, the air caps 5 set on the first vent 41, the second vent 42, and the third vent 31 are arranged at equal intervals, so that the air caps 5 are arranged in a consistent manner throughout the furnace 1, thereby improving the uniformity of air distribution.

[0048] In some exemplary embodiments, reference is made to Figure 1 The air caps 5 installed on the first vent 41, the second vent 42, and the third vent 31 are coplanar on the side facing the upper space of the furnace 1.

[0049] In this embodiment, the air caps 5 installed on the first vent 41, the second vent 42, and the third vent 31 are coplanar on the side facing the upper space of the furnace 1, so that the air caps 5 arranged on the top of the bellows 3, as well as the air caps 5 arranged on the top and side walls of the multiple branch air pipes 4, are at the same height relative to the bottom of the furnace 1. Furthermore, the air caps 5 in each area inside the furnace 1 can fill the cross-section of the furnace 1 when put together, so that there are air caps 5 everywhere on the cross-section of the furnace 1, ensuring the uniformity of air distribution inside the furnace 1.

[0050] Furthermore, the diameter of the bellows 3, the diameter and number of the branch air pipes 4, the number of air caps 5 in each area, and the spacing between two adjacent air caps 5 can be adjusted according to the diameter of the furnace 1 and the size of the air caps 5.

[0051] Furthermore, the ratio of the cross-sectional area of ​​the bellows 3 to the sum of the cross-sectional areas of the multiple branch air ducts 4 is adjusted according to the diameter of the furnace 1. As the diameter of the furnace 1 increases, the proportion of the cross-sectional area of ​​the bellows 1 increases, and the ratio of the two can generally be adjusted between 1 and 3 times.

[0052] In some exemplary embodiments, reference is made to Figures 1-2The bellows 3 is constructed as a cylindrical body with a roughly circular cross-section, so that the amount of expansion of the bellows 3 in the circumferential direction is uniform during the process of thermal expansion.

[0053] In this embodiment, the bellows 3 is constructed as a cylindrical body with a roughly circular cross-section, ensuring uniform expansion of the circumferential sidewalls during thermal expansion, thus eliminating the problem of uneven heating causing weld cracking. Compared to bellows 3 of other shapes, the roughly circular cross-section is structurally more reasonable. When heated, the bellows 3 can expand freely upwards in the axial direction without restriction.

[0054] It should be noted that, in this embodiment, the height of the bellows 3 can be appropriately increased, provided that the height of the furnace 1 is within acceptable limits, so that the airflow is distributed more evenly within the bellows 3. In other words, the height of the bellows 3 can be appropriately increased according to the height of the furnace 1 to increase the flow distance of the airflow within the bellows 3, allowing the airflow to diffuse fully within the bellows 3, thereby improving the uniformity of the airflow distribution within the bellows 3.

[0055] Figure 3 This is a schematic diagram showing the installation relationship between the air box, main air duct, branch air duct, and slag discharge pipe of the air distribution device for a fluidized bed according to an embodiment of this utility model.

[0056] In some exemplary embodiments, reference is made to Figure 3 Two slag discharge pipes 7 extending downward along the height direction are provided at the bottom of the furnace 1. The two slag discharge pipes 7 are symmetrically arranged about the axis of the furnace 1. Each slag discharge pipe 7 is located outside the wind box 3 and the branch air pipe 4, so that the thermal expansion of the slag discharge pipe 7 is independent of the wind box 3 and the branch air pipe 4.

[0057] In this embodiment, two slag discharge pipes 7 extending along the height direction are provided at the bottom of the furnace 1, and the two slag discharge pipes 7 are symmetrically arranged about the axis of the furnace 1. Each slag discharge pipe 7 is located outside the wind box 3 and the branch air pipe 4, so that the slag discharge pipe 7 is in the space inside the furnace 1 and outside the wind box 3 and the branch air pipe 4. Therefore, during the thermal expansion process, the thermal expansion of the slag discharge pipe 7 is independent of the wind box 3 and the branch air pipe 4. In other words, during the thermal expansion process, the thermal expansion of the slag discharge pipe 7 is not constrained by the wind box 3 and the branch air pipe 4, allowing the slag discharge pipe 7 to expand freely when heated.

[0058] Furthermore, the slag discharge pipe 7 is arranged outside the air box 3 and the branch air pipe 4, avoiding problems such as weld cracking due to uneven heating between the slag discharge pipe 7 and the air box 3 caused by the slag discharge pipe 7 passing through the air box 3. This is because when the slag discharge pipe 7 passes through the air box 3, the wall surface of the slag discharge pipe 7 is at a high temperature during slag discharge. The local temperature of the upper and lower surfaces of the air box 3 in contact with the slag discharge pipe 7 is different from the temperature of other parts of the air box 3, resulting in different heating and expansion in different parts of the air box 3, causing the weld to crack due to the expansion difference.

[0059] In some exemplary embodiments, reference is made to Figure 1 The furnace chamber 1 is lined with refractory material 6 to enclose a portion of the main air duct 2, air box 3, branch air duct 4, and slag discharge pipe 7 located inside the furnace chamber 1.

[0060] In this embodiment, refractory material 6 is filled in the area from the bottom of the furnace 1 to the lower side of the wind cap 5 inside the furnace 1 to encase part of the main air pipe 2, wind box 3, branch air pipe 4 and slag discharge pipe 7 located inside the furnace 1, so as to protect the main air pipe 2, wind box 3, branch air pipe 4 and slag discharge pipe 7.

[0061] In other words, the main air duct 2, the air box 3, and the branch air duct 4 are arranged inside the refractory material 6 to protect the main air duct 2, the air box 3, and the branch air duct 4 from high temperature and wear.

[0062] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. An air distribution device for a fluidized bed, characterized in that, include: Furnace (1); The main air duct (2) extends along the height direction and passes through the bottom of the furnace (1), and is suitable for receiving external airflow; The bellows (3) is installed inside the furnace (1) and is connected to the end of the main air duct (2); as well as Multiple branch pipes (4) are evenly arranged on the side wall of the air box (3) in the circumferential direction and are connected to the interior of the air box (3). A section of each branch pipe (4) near the tail end extends upward in the height direction, and at least one air cap (5) extending upward in the height direction is installed near the tail end of each branch pipe (4) to form a uniformly distributed airflow inside the furnace (1).

2. The air distribution device for a fluidized bed according to claim 1, characterized in that, The branch duct (4) is constructed as an L-shaped bend, with one end connected to the side wall of the bellows (3) and the other end extending toward the space above the furnace (1).

3. The air distribution device for a fluidized bed according to claim 1, characterized in that, The number of branch air pipes (4) arranged along the circumferential direction on the side wall of the air box (3) is even, and the multiple branch air pipes (4) are symmetrically arranged about the radial extension line of the cross section of the furnace (1).

4. The air distribution device for a fluidized bed according to claim 1, characterized in that, On the side wall of each branch duct (4) extending toward the upper space of the furnace (1), a plurality of first ventilation holes (41) are evenly arranged in the circumferential direction, and each first ventilation hole (41) is equipped with a wind cap (5) extending upward in the height direction.

5. The air distribution device for a fluidized bed according to claim 4, characterized in that, Each of the branch ducts (4) is also provided with a second vent (42) at the top center, and a wind cap (5) extending upward along the height direction is installed on the second vent (42).

6. The air distribution device for a fluidized bed according to claim 5, characterized in that, The top of the bellows (3) is evenly provided with a plurality of third ventilation holes (31), and each of the third ventilation holes (31) is fitted with a wind cap (5) that extends upward along the height direction.

7. The air distribution device for a fluidized bed according to claim 6, characterized in that, The air caps (5) installed on the first vent (41), the second vent (42), and the third vent (31) are coplanar on the side facing the upper space of the furnace (1).

8. The air distribution device for a fluidized bed according to claim 1, characterized in that, The bellows (3) is constructed as a cylindrical body with a circular cross-section, so that the amount of expansion of the bellows (3) in the circumferential direction is uniform during the process of thermal expansion.

9. The air distribution device for a fluidized bed according to claim 1, characterized in that, The bottom of the furnace (1) is provided with two slag discharge pipes (7) extending downward along the height direction. The two slag discharge pipes (7) are symmetrically arranged about the axis of the furnace (1). Each slag discharge pipe (7) is located outside the wind box (3) and the branch air pipe (4), so that the thermal expansion of the slag discharge pipe (7) is independent of the wind box (3) and the branch air pipe (4).

10. The air distribution device for a fluidized bed according to claim 9, characterized in that, The furnace chamber (1) is filled with refractory material (6) to enclose a portion of the main air duct (2), the wind box (3), the branch air duct (4), and the slag discharge pipe (7) located inside the furnace chamber (1).

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