Multistage aeration device for sewage treatment

Abstract

The utility model discloses a multistage aeration device for sewage treatment. The multistage aeration device mainly comprises an inverted umbrella aeration mechanism, a water bottom aeration mechanism and a transmission mechanism, the device is mainly used for enabling a water body to make contact with air in a sewage treatment tank, the oxygen content of the water body is increased, an arranged cylindrical pin is inserted into a first rotating disc with a hole, so that a water bottom aeration mechanism rotates in the direction opposite to that of an inverted umbrella aeration mechanism, and then the water flow movement directions of the surface and the bottom of the water body are opposite; the contact area of the water body and the air is further increased. The device solves the problems that in the sewage treatment aeration process, a single inverted umbrella-shaped aeration effect is poor, the working efficiency is low, and multiple inverted umbrella-shaped aeration occupies the upper space of a sewage pool; the working efficiency of sewage treatment can be improved, the operation cost is reduced, and the sewage treatment quality is improved.

Description

Technical Field

[0001] This application relates to the technical field of sewage treatment, and particularly to a multi-stage aeration device for sewage treatment. Background Art

[0002] In modern industrial production and daily life, a large amount of various types of sewage is generated, which contains a large amount of organic matter, nitrogen, phosphorus, microorganisms, etc. If discharged into nature, it will cause eutrophication of water bodies, trigger a large number of reproductions of algae and other aquatic plants, consume oxygen in the water, cause hypoxia in the water body, and even produce stench and death phenomena. If such sewage is directly discharged without treatment, it will cause serious harm to the environment and human health. After sewage treatment, it can be transformed into normal industrial water or domestic water that meets the regulations. Therefore, it is necessary to purify sewage. Existing sewage treatment mostly uses sewage treatment ponds and treats sewage in a biological or chemical form. Among them, aeration equipment is mostly used to inject air into the water body or increase the contact between the water body and air to make the water body in an oxygen-rich state. However, the current inverted umbrella-type aeration device cannot effectively disturb and aerate the water body at the bottom of the sewage pond. At the same time, using multiple inverted umbrella-type aeration devices with multiple groups of drive motors occupies too much space on the top of the sewage pond, which easily leads to poor aeration effect and affects the sewage treatment effect and efficiency.

[0003] For example, an inverted umbrella-type aerator with the publication number of CN212954515U has a structure including a motor, a coupling, a speed reducer, and an impeller shaft. Among them: the motor is arranged vertically downward, the rotor of the motor is connected to the power input shaft of the speed reducer through a coupling, an inverted umbrella seat is vertically downward installed below the speed reducer, the impeller shaft is vertically downward installed on the inverted umbrella seat, the power output shaft of the speed reducer is connected to the upper end of the impeller shaft, a blade seat is fixedly installed at the lower end of the impeller shaft, an inverted cone body is installed on the lower surface of the blade seat, and several blades are evenly distributed along the circumferential direction of the blade seat. The blades are set as long trapezoids, which can effectively enhance the water-gas mixing effect, increase the diving depth of the aerator, increase the oxygenation amount, and improve the aeration effect; a lifting device is arranged between the lower part of the speed reducer and the ground plane. The above-mentioned aeration device only plays a role in improving the oxygenation ability of the inverted umbrella-type aeration device on the sewage surface and cannot oxygenate the water body at the bottom and effectively disturb the water body. Therefore, this application designs a multi-stage aeration device for sewage treatment that can simultaneously disturb the surface and bottom of the sewage pond and aerate at the same time. Summary of the Utility Model

[0004] The purpose of the present utility model is to provide a multi-stage aeration device for sewage treatment, aiming to solve the above existing problems.

[0005] To achieve the above object, the present utility model provides the following technical solution: A multi-stage aeration device for sewage treatment, comprising an inverted umbrella aeration mechanism, a bottom aeration mechanism, and a transmission mechanism; the inverted umbrella aeration mechanism is fixedly connected to the transmission mechanism, the bottom aeration mechanism is fixedly connected to the transmission mechanism, and the transmission mechanism is arranged in the middle of the sewage treatment pool gallery; inside the transmission mechanism, there are a first fixed disk, a cylindrical pin, and a first rotating disk. There are holes on the first rotating disk, the cylindrical pin passes through the holes, the upper part of the first rotating disk is rotationally connected to the transmission mechanism, the lower part of the cylindrical pin is fixedly connected to the transmission mechanism, the first fixed disk is slidably connected to the transmission mechanism, the first rotating disk is arranged inside the first fixed disk, and the first rotating disk is driven by the transmission mechanism to rotate and then friction with the inner wall of the first fixed disk, thereby pushing the cylindrical pin to rotate reversely and decelerate around the central axis of the transmission mechanism, so that the bottom aeration mechanism rotates reversely and decelerates relative to the inverted umbrella aeration mechanism.

[0006] Through the cylindrical pin arranged in the hole of the first rotating disk, the cylindrical pin is driven by the first rotating disk to drive the bottom aeration mechanism to rotate reversely relative to the inverted umbrella aeration mechanism, making the water body in the sewage pool flow more turbulently, increasing the contact between the water body and the air, and improving the sewage treatment efficiency.

[0007] Furthermore, the inverted umbrella aeration mechanism includes a connecting rod and a rotating cone. The upper part of the rotating cone is bolted to the lower part of the connecting rod, the upper part of the connecting rod is fixedly connected to the transmission mechanism, and there are three groups of connecting rods and rotating cones. The three groups of rotating cones rotate synchronously on the water surface for aeration, and at the same time disturb the upper layer of the water body to make the upper layer of the water body rotate, enhancing the aeration effect on the water surface. The bottom aeration mechanism includes an aeration pipe, an aeration disk, a stirring plate, and an air pump; the aeration pipe is inserted into the transmission mechanism, there are several aeration disks evenly arranged on the upper part of the aeration pipe, there are several stirring plates evenly arranged on the upper part of the aeration pipe, and the air pump is sleeved in the middle of the transmission mechanism. The gas is sent into the aeration disk through the arranged aeration pipe for aeration at the bottom of the water body, and the bottom water body is stirred by the stirring plate, improving the aeration effect of the bottom water body and strengthening the contact area between the water body and the air.

[0008] Furthermore, the transmission mechanism includes a motor, a rotating rod, a rotating pair, a second rotating disk, a Z-shaped rod, a second fixed disk, a crank, and a rotating base; the motor is arranged in the middle of the sewage treatment pool bridge, the output end of the motor passes through the bridge and is vertically arranged towards the water surface, one end of the rotating pair is fixedly connected to the output end of the motor, and the other end of the rotating pair is rotatably connected to the second rotating disk, so that the second rotating disk rotates circumferentially around the axis of the motor without self-rotation. The upper part of the Z-shaped rod is rotatably connected to the second rotating disk, and the lower part of the Z-shaped rod is rotatably connected to the second fixed disk. The upper part of the connecting rod passes through the second fixed disk and is fixedly connected to the lower part of the Z-shaped rod; the upper end of the rotating rod passes through the second fixed disk and is fixedly connected to the lower end of the Z-shaped rod, the lower end of the rotating rod is fixedly connected to the crank, the lower part of the end of the crank away from the rotating rod is rotatably connected to the first rotating disk, the upper part of the rotating base is fixedly connected to the cylindrical pin, and the lower part of the rotating base is rotatably connected to the bottom of the sewage treatment pool, so that the rotating base rotates around its own axis. There are four groups of Z-shaped rods, three of which are evenly arranged circumferentially under the second rotating disk, and the other group of Z-shaped rods is arranged in the middle of the second rotating disk. The rotating rod is fixedly connected to the Z-shaped rod arranged in the middle of the second rotating disk. Through the four groups of Z-shaped rods arranged, the three rotating cones are driven by the same power and rotate synchronously, effectively reducing the space occupied in the upper part of the sewage pool. Through the crank arranged, the first rotating disk is driven to rotate reversely on the inner wall of the first fixed disk, driving the stirring plate to rotate reversely, so that the flow directions of the upper water body and the lower water body are opposite, making the water body flow disorderly, and further increasing the contact time between the water body and the air.

[0009] Furthermore, the rotating base includes a rotating seat and a connecting rod; the connecting rod is fixedly inserted into the rotating seat, the other end of the connecting rod is slidably connected to the first fixed disk, the upper part of the rotating seat is fixedly connected to the cylindrical pin, the aeration pipeline is inserted into the rotating seat, and the lower part of the rotating seat is rotatably connected to the bottom of the sewage treatment pool. A hollow part is provided in the middle of the rotating rod, the rotating rod is of a hollow design, an air pump is sleeved outside the hollow part, and an air pipe is arranged inside the rotating rod. The air pipe is communicated to the aeration pipeline through the rotating base. The air pump can pump air into the aeration pipeline and aerate at the bottom of the water through the aeration disk, cooperating with the inverted umbrella-shaped aeration on the upper body surface to form a multi-stage aeration device, improving the all-round aeration effect of the sewage pool. There are three groups of rotating cones and connecting rods respectively. The upper part of the connecting rod passes through the second fixed disk and is fixedly connected to the lower part of the Z-shaped rod. The three rotating cones aerate the water surface synchronously and occupy relatively less space in the upper part of the sewage pool.

[0010] Compared with the prior art, it has the following beneficial effects:

[0011] The utility model provides a multi-stage aeration device for sewage treatment. When using this device to aerate and oxygenate the water body to be treated in a sewage pool, through the cylindrical pin arranged in the hole of the first rotating disk, the cylindrical pin is driven by the first rotating disk to drive the underwater aeration mechanism to rotate in the opposite direction relative to the inverted umbrella aeration mechanism, making the water body in the sewage pool flow more turbulently, increasing the contact between the water body and air, and improving the sewage treatment efficiency; through the arranged crank to drive the first rotating disk to rotate in the opposite direction on the inner wall of the first fixed disk to drive the stirring plate to rotate in the opposite direction, making the flow directions of the upper water body and the lower water body opposite, making the water body flow more irregularly, and further increasing the contact duration between the water body and air; through the arranged four groups of Z-shaped rods, the three rotating cones are driven by the same power to rotate synchronously, reducing the occupation of the upper space of the sewage pool. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is an overall schematic diagram of a multi-stage aeration device for sewage treatment according to the utility model;

[0013] Figure 2 is a partial enlarged schematic diagram of A of the utility model;

[0014] Figure 3 is a partial enlarged schematic diagram of B of the utility model;

[0015] Figure 4 is a schematic diagram of the hollow part of a multi-stage aeration device for sewage treatment according to the utility model.

[0016] In the figure: 1 - inverted umbrella aeration mechanism; 11 - connecting rod; 12 - rotating cone; 2 - underwater aeration mechanism; 21 - aeration pipeline; 22 - aeration disk; 23 - stirring plate; 24 - air pump; 3 - transmission mechanism; 31 - motor; 32 - rotating rod; 321 - hollow part; 33 - rotating pair; 34 - second rotating disk; 35 - Z-shaped rod; 36 - second fixed disk; 37 - crank; 38 - rotating base; 381 - rotating seat; 382 - connecting rod; 4 - first fixed disk; 5 - cylindrical pin; 6 - first rotating disk; 7 - hole. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] Next, the technical solutions in the embodiments of the utility model will be clearly and completely described in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only a part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the utility model.

[0018] Please refer to Figures 1 to 4As shown in the figure, the present utility model provides the following technical solution: A multi-stage aeration device for sewage treatment, including an inverted umbrella aeration mechanism 1, a bottom aeration mechanism 2, and a transmission mechanism 3; the inverted umbrella aeration mechanism 1 is fixedly connected to the transmission mechanism 3, the bottom aeration mechanism 2 is fixedly connected to the transmission mechanism 3, and the transmission mechanism 3 is arranged in the middle of the sewage treatment pool bridge; inside the transmission mechanism 3, there are a first fixed disk 4, a cylindrical pin 5, and a first rotating disk 6. A hole 7 is provided on the first rotating disk 6. The cylindrical pin 5 passes through the hole 7. The upper part of the first rotating disk 6 is rotatably connected to the transmission mechanism 3, and the lower part of the cylindrical pin 5 is fixedly connected to the transmission mechanism 3. The first fixed disk 4 is slidably connected to the transmission mechanism 3. The first rotating disk 6 is arranged inside the first fixed disk 4. The first rotating disk 6 is driven by the transmission mechanism 3 to rotate and then rubs against the inner wall of the first fixed disk 4, thereby driving the cylindrical pin 5 to rotate in the reverse direction and decelerate around the central axis of the transmission mechanism 3, so that the bottom aeration mechanism 2 rotates in the reverse direction and decelerates relative to the inverted umbrella aeration mechanism 1. The cylindrical pin 5 meshes with the inner wall of the hole 7, and the radius difference between the cylindrical pin 5 and the hole 7 is equal to the eccentricity of the crank 37.

[0019] As another embodiment, as Figure 1 and Figure 2 shown, the inverted umbrella aeration mechanism 1 includes a connecting rod 11 and a rotating cone 12. The upper part of the rotating cone 12 is bolted to the lower part of the connecting rod 11. The upper part of the connecting rod 11 is fixedly connected to the transmission mechanism 3. Both the connecting rod 11 and the rotating cone 12 are provided with three groups. The connecting rod 11 is driven by the transmission mechanism 3 to rotate, and then drives the rotating cone 12 to rotate on the water surface of the sewage pool, forming a water curtain that diverges around, increasing the oxygen content in the water body. At the same time, a negative pressure area is formed at the rear of the rotating cone 12, pressing oxygen into the water body and driving the upper layer of water to stir.

[0020] See Figure 1 and Figure 2 , the bottom aeration mechanism 2 includes an aeration pipe 21, an aeration disk 22, a stirring plate 23, and an air pump 24; the aeration pipe 21 is inserted into the transmission mechanism 3. A number of aeration disks 22 are evenly arranged on the upper part of the aeration pipe 21. A number of stirring plates 23 are evenly arranged on the upper part of the aeration pipe 21. The air pump 24 is sleeved in the middle of the transmission mechanism 3. The aeration pipe 21 is driven by the transmission mechanism 3 to rotate around the central axis of the transmission mechanism 3, and then the stirring plate 23 stirs the water body at the bottom layer of the water body. The air pump 24 pumps air into the transmission mechanism 3 and then into the aeration pipe 21. Finally, the aeration disk 22 releases air into the bottom layer of the water body at the bottom of the water body, realizing synchronous aeration of the upper and lower layers of the water body.

[0021] As another embodiment, as Figure 1 and Figure 3As shown in the figure, the transmission mechanism 3 includes a motor 31, a rotating rod 32, a rotating pair 33, a second rotating disk 34, a Z-shaped rod 35, a second fixed disk 36, a crank 37, and a rotating base 38; the motor 31 is arranged in the middle of the sewage treatment pool bridge, and the output end of the motor 31 passes through the bridge and is vertically arranged towards the water surface. One end of the rotating pair 33 is fixedly connected to the output end of the motor 31, and the other end of the rotating pair 33 is rotatably connected to the second rotating disk 34, so that the second rotating disk 34 rotates circumferentially around the axis of the motor 31 without self-rotation. The upper part of the Z-shaped rod 35 is rotatably connected to the second rotating disk 34, and the lower part of the Z-shaped rod 35 is rotatably connected to the second fixed disk 36. The upper part of the connecting rod 11 passes through the second fixed disk 36 and is fixedly connected to the lower part of the Z-shaped rod 35; the upper end of the rotating rod 32 passes through the second fixed disk 36 and is fixedly connected to the lower end of the Z-shaped rod 35, and the lower end of the rotating rod 32 is fixedly connected to the crank 37. The lower part of the end of the crank 37 away from the rotating rod 32 is rotatably connected to the first rotating disk 6. The upper part of the rotating base 38 is fixedly connected to the cylindrical pin 5, and the lower part of the rotating base 38 is rotatably connected to the bottom of the sewage treatment pool, so that the rotating base 38 rotates around its own axis.

[0022] Driven by the motor 31, the rotating pair 33 rotates, and then drives the second rotating disk 34 to perform a circumferential motion around the output end of the motor 31 without self-rotation. The Z-shaped rod 35 is driven by the second rotating disk 34 to rotate, and then drives the connecting rod 11 to rotate, so that the rotating cone 12 performs rotary aeration. At the same time, the rotation of the Z-shaped rod 35 drives the rotating rod 32 to rotate, drives the crank 37 to rotate, and then drives the inner wall of the first rotating disk 6 and the first fixed disk 4 to rub against each other. Through the rotational connection between the first rotating disk 6 and the crank 37, the first rotating disk 6 rotates in the opposite direction and decelerates relative to the rotating rod 32. Then, it drives the cylindrical pin 5 engaged with the hole 7 to perform a circumferential motion in the opposite direction and decelerate relative to the rotating rod 32 around the axis, so that the rotating base 38 rotates in the opposite direction and decelerates, and then drives the bottom aeration mechanism 2 to rotate in the opposite direction and decelerate, making the direction of the bottom water flow opposite to that of the upper water flow.

[0023] See Figure 1 As shown in

[0024] See Figure 3, the rotating base 38 includes a rotating seat 381 and a connecting rod 382; the connecting rod 382 is fixedly inserted into the rotating seat 381, the other end of the connecting rod 382 is slidably connected to the first fixed disk 4, the upper part of the rotating seat 381 is fixedly connected to the cylindrical pin 5, the aeration pipeline 21 is inserted into the rotating seat 381, and the lower part of the rotating seat 381 is rotatably connected to the bottom of the sewage treatment tank. The rotating seat 381 is driven by the cylindrical pin 5 to rotate in reverse at a reduced speed, driving the aeration pipeline 21 to rotate, so that the stirring plate 23 stirs the bottom water body. The first fixed disk 4 is fixed to the outside of the first rotating disk 6 through the connecting rod 382. When the rotating seat 381 rotates, the connecting rod 382 slides in the chute on the outer wall of the first fixed disk 4 to prevent the first fixed disk 4 from rotating.

[0025] As another embodiment, as Figure 1 and Figure 4 shown, a hollow portion 321 is provided in the middle of the rotating rod 32. The rotating rod 32 is of a hollow design. The air pump 24 is sleeved outside the hollow portion 321. An air pipe is provided inside the rotating rod 32, and the air pipe is communicated to the aeration pipeline 21 through the rotating base 38.

[0026] Refer to Figure 1 , there are three groups of rotating cones 12 and connecting rods 11. The upper part of the connecting rod 11 passes through the second fixed disk 36 and is fixedly connected to the lower part of the Z-shaped rod 35, so that the three groups of rotating cones 12 rotate synchronously on the water surface.

[0027] Working principle: When in use, the device is installed in the sewage tank, and then the motor 31 is started. The output end of the motor 31 drives the rotating pair 33 to rotate, and then drives the second rotating disk to perform a circular motion, so that the three groups of Z-shaped rods 35 drive the three groups of inverted umbrella aeration mechanisms 1 to rotate synchronously on the water surface to achieve water surface aeration and stirring. The rotation of the Z-shaped rod 35 drives the rotating rod 32 to rotate at the same time. Through the friction between the first rotating disk 6 and the first fixed disk 4, the cylindrical pin 5 makes a circular motion of reverse deceleration, driving the bottom aeration mechanism 2 to rotate in reverse, and then reversely stirring the bottom water body through the stirring plate 23. The air pump 24 pumps air into the aeration pipeline 21, and the air is released into the bottom water body through the aeration disk 22 at the bottom of the water body to perform multi-stage aeration operation.

[0028] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A multi-stage aeration device for sewage treatment, characterized in that , comprising an inverted umbrella aeration mechanism (1), an underwater aeration mechanism (2) and a transmission mechanism (3); the inverted umbrella aeration mechanism (1) is fixedly connected to the transmission mechanism (3), the underwater aeration mechanism (2) is fixedly connected to the transmission mechanism (3), and the transmission mechanism (3) is arranged in the middle of the corridor bridge of the sewage treatment pool; the transmission mechanism (3) is provided with a first fixed disk (4), a cylindrical pin (5) and a first rotating disk (6), the first rotating disk (6) is provided with a hole (7), the cylindrical pin (5) passes through the hole (7), and the upper part of the first rotating disk (6) is connected to the The transmission mechanism (3) is rotatably connected, the lower part of the cylindrical pin (5) is fixedly connected to the transmission mechanism (3), the first fixed disk (4) is slidably connected to the transmission mechanism (3), the first rotating disk (6) is arranged inside the first fixed disk (4), the first rotating disk (6) is driven by the transmission mechanism (3) to rotate and then rubs against the inner wall of the first fixed disk (4), thereby pushing the cylindrical pin (5) to rotate in the reverse direction around the central axis of the transmission mechanism (3), so that the underwater aeration mechanism (2) rotates in the reverse direction relative to the inverted umbrella aeration mechanism (1).

2. The multi-stage aeration device for sewage treatment according to claim 1, characterized in that: The inverted umbrella aeration mechanism (1) comprises a connecting rod (11) and a rotating cone (12); the upper portion of the rotating cone (12) is bolted to the lower portion of the connecting rod (11); the upper portion of the connecting rod (11) is fixedly connected to the transmission mechanism (3); and the connecting rod (11) and the rotating cone (12) are each provided with three groups.

3. The multi-stage aeration device for sewage treatment according to claim 2, characterized in that: The underwater aeration mechanism (2) comprises an aeration pipe (21), an aeration disc (22), a stirring plate (23) and an air pump (24); the aeration pipe (21) is plugged into the transmission mechanism (3); a plurality of aeration discs (22) are provided and are evenly arranged on the upper part of the aeration pipe (21); a plurality of stirring plates (23) are provided and are evenly arranged on the upper part of the aeration pipe (21); and the air pump (24) is sleeved in the middle of the transmission mechanism (3).

4. The multi-stage aeration device for sewage treatment according to claim 3, characterized in that: The transmission mechanism (3) comprises a motor (31), a rotating rod (32), a rotating pair (33), a second rotating disk (34), a Z-shaped rod (35), a second fixed disk (36), a crank (37) and a rotating base (38); the motor (31) is arranged in the middle of the corridor bridge of the sewage treatment pool; the output end of the motor (31) passes through the corridor bridge and is vertically arranged in a direction close to the water surface; one end of the rotating pair (33) is fixedly connected to the output end of the motor (31); the other end of the rotating pair (33) is rotationally connected to the second rotating disk (34), so that the second rotating disk (34) rotates in a circle around the axis of the motor (31) without rotating itself; the upper part of the Z-shaped rod (35) is rotationally connected to the second rotating disk (34) The lower part of the Z-shaped rod (35) is rotatably connected to the second fixed disk (36), and the upper part of the connecting rod (11) passes through the second fixed disk (36) and is fixedly connected to the lower part of the Z-shaped rod (35); the upper end of the rotating rod (32) passes through the second fixed disk (36) and is fixedly connected to the lower end of the Z-shaped rod (35), and the lower end of the rotating rod (32) is fixedly connected to the crank (37), and the lower part of the crank (37) away from the rotating rod (32) is rotatably connected to the first rotating disk (6), the upper part of the rotating base (38) is fixedly connected to the cylindrical pin (5), and the lower part of the rotating base (38) is rotatably connected to the bottom of the sewage treatment tank, so that the rotating base (38) rotates around itself as an axis.

5. The multi-stage aeration device for sewage treatment according to claim 4, characterized in that: The Z-shaped rods (35) are provided in four groups, of which three groups of the Z-shaped rods (35) are evenly arranged at the lower part of the second rotating disk (34), and the other group of the Z-shaped rods (35) is arranged in the middle of the second rotating disk (34). The rotating rod (32) is fixedly connected to the Z-shaped rods (35) arranged in the middle of the second rotating disk (34).

6. The multi-stage aeration device for sewage treatment according to claim 5, characterized in that: The rotating base (38) comprises a rotating seat (381) and a connecting rod (382); the connecting rod (382) is fixedly plugged into the rotating seat (381), the other end of the connecting rod (382) is slidably connected to the first fixed disk (4), the upper part of the rotating seat (381) is fixedly connected to the cylindrical pin (5), the aeration pipe (21) is plugged into the rotating seat (381), and the lower part of the rotating seat (381) is rotatably connected to the bottom of the sewage treatment tank.

7. The multi-stage aeration device for sewage treatment according to claim 4, characterized in that: A hollow portion (321) is provided in the middle of the rotating rod (32). The rotating rod (32) is of hollow design. The air pump (24) is sleeved on the outside of the hollow portion (321). An air pipe is provided inside the rotating rod (32). The air pipe is connected to the aeration pipe (21) through the rotating base (38).

8. The multi-stage aeration device for sewage treatment according to claim 4, characterized in that: The rotating cone (12) and the connecting rod (11) are each provided with three groups, and the upper portion of the connecting rod (11) passes through the second fixed plate (36) and is fixedly connected to the lower portion of the Z-shaped rod (35).

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