CN116718037A

CN116718037A - Round cooling tower

Info

Publication number: CN116718037A
Application number: CN202310610027.1A
Authority: CN
Inventors: 黄亚连; 刘凯松; 杨学强; 王德利; 袁令军
Original assignee: Tianjin Yuan Tai De Run Pipe Group Co ltd
Current assignee: Tianjin Yuan Tai De Run Pipe Group Co ltd
Priority date: 2023-05-26
Filing date: 2023-05-26
Publication date: 2023-09-08

Abstract

The application discloses a round cooling tower, which relates to the technical field of cooling towers, and comprises a tower body, wherein a main water supply pipe is arranged in the center of the tower body, and is communicated with a first branch pipe group and a second branch pipe group; the tower body is internally provided with a first cooling system and a second cooling system, the first branch pipe group is arranged above the first cooling system, the second branch pipe group is arranged above the second cooling system, and the first cooling system is arranged above the second branch pipe group; the tower body bottom is provided with the water collector, and first cooling system and second cooling system all communicate with the water collector, and the intercommunication has outlet conduit on the water collector. The application has the effect of improving the cooling efficiency of the cooling tower.

Description

Round cooling tower

Technical Field

The application relates to the technical field of cooling towers, in particular to a round cooling tower.

Background

The cooling tower is one kind of widely used thermodynamic equipment and consists of stuffing, exhaust equipment, water collecting pond, water conveying system and outer protecting structure.

The working principle is that circulating cooling water enters the cooling tower through the water delivery system, cold dry air in the surrounding environment is sucked into the cooling tower by the air suction device, the top end of the cooling tower is provided with the air exhaust device, and the water temperature is reduced by heat conduction between the circulating cooling water and the cold dry air and evaporation of the circulating cooling water to take away gasification latent heat. The circulating cooling water passes through the filler, and the filler enables the circulating cooling water entering the cooling tower to form tiny water drops or thin water films as far as possible, so that the contact area and the contact time of the water and the air are increased, and the cooling efficiency of the cooling tower is improved. The circulating cooling water is discharged from the water outlet after passing through the filler in the cooling tower.

However, when the amount of circulating cooling water discharged into the cooling tower is large and the external temperature is high, the cooling efficiency of the cooling tower to the circulating cooling water is low due to the limited amount of air flowing into the cooling tower and the thick thickness of the filler.

Disclosure of Invention

In order to improve the cooling efficiency of the cooling tower, the application provides a circular cooling tower.

The application provides a round cooling tower, which adopts the following technical scheme:

a circular cooling tower comprises a tower body, wherein a main water supply pipe is arranged in the center of the tower body, and a first branch pipe group and a second branch pipe group are communicated with the main water supply pipe;

the tower body is internally provided with a first cooling system and a second cooling system, the first branch pipe group is arranged above the first cooling system, the second branch pipe group is arranged above the second cooling system, and the first cooling system is arranged above the second branch pipe group;

the tower body bottom is provided with the water collector, first cooling system and second cooling system all with the water collector intercommunication, just the intercommunication has outlet conduit on the water collector.

Through adopting above-mentioned technical scheme, circulating cooling water can get into the tower body from the main delivery pipe in, in the main delivery pipe respectively transported to first branch nest of tubes and second branch nest of tubes, the water in the first branch nest of tubes cools off through first cooling system, and the water in the second branch nest of tubes cools off through second cooling system, and in the circulating cooling water after the cooling was collected to the water collector at last, from outlet conduit discharge, accomplish the cooling of circulating cooling water.

The first cooling system and the second cooling system are arranged, so that the cooling efficiency of the circulating cooling water can be improved, and the cooling effect of the circulating cooling water can be still good when the circulating cooling water quantity in the cooling tower is increased.

Optionally, an air duct is vertically arranged in the center of the tower body, and the main water supply pipe is positioned in the air duct;

the first cooling system comprises a packing ring and a secondary exhaust group, and the packing ring is arranged between the outer wall of the air duct and the inner wall of the tower body;

the auxiliary exhaust group comprises a plurality of auxiliary exhaust fans arranged on the side wall of the tower body and a plurality of auxiliary exhaust fans arranged on the top wall of the tower body.

Through adopting above-mentioned technical scheme, in the circulating cooling water in the first branch nest of tubes falls into first cooling system downwards, because the space between wind channel outer wall and the tower body inner wall has been shutoff to the packing ring for circulating cooling water in the first branch nest of tubes can only follow the packing ring and pass through, the packing can disperse circulating cooling water into tiny water droplet or water film, the auxiliary exhaust fan of setting up at the tower body lateral wall simultaneously brings outside dry and cold air into the tower body, the air upwards circulates, and discharge from the auxiliary exhaust fan at top of the tower, the air circulates to the packing ring top from the bottom of packing ring, at this in-process, air and circulating cooling water carry out heat exchange, make circulating cooling water partial evaporation, the evaporation process, circulating cooling water evaporation in-process heat absorption, thereby reach the purpose of cooling.

Optionally, the second cooling system comprises a main exhaust group and a filler block arranged between the end of the air duct close to the water receiving disc and the water receiving disc, and the filler block is fixedly connected with the inner wall of the tower body;

the main exhaust group comprises a main exhaust fan arranged on the side wall of the tower body and close to the bottom, and a main exhaust fan arranged at one end of the air duct far away from the water receiving disc.

Through adopting above-mentioned technical scheme, when the circulating cooling water volume that gets into in the cooling tower is great, part circulating cooling water falls into in the second cooling system from the second branch bank, the circulating cooling water that the second branch bank falls gets into the filler piece at first, at this moment, the main air exhauster that sets up in the tower body bottom is to the internal dry cooling air that draws in of tower, the air upwards circulates through the filler piece, after carrying out the heat exchange with the circulating cooling water in the filler piece, along with the exhaust of main air exhauster for outside the cooling tower is discharged along the wind channel to the vapor that has the heat, thereby accomplish the cooling of whole second cooling system to circulating cooling water.

Optionally, a water guide surface is arranged between the packing ring and the second branch pipe group, the water guide surface is annular, an inner annular wall of the water guide surface is fixedly connected with the outer wall of the air duct, and the water guide surface is provided with an inclined surface gradually approaching to the water receiving disc from the air duct to the side wall of the tower body.

Through adopting above-mentioned technical scheme, because the second cooling system sets up in the below of first cooling system, for making first cooling system and second cooling system can the individual operation, be provided with the water guide surface, the circulation cooling water after the cooling of first cooling system drips to the water guide surface on to can flow along water guide surface to tower body lateral wall, finally in the drain water pan is received through the drainage channel drainage, the discharge cooling tower.

Optionally, a plurality of ribs are fixed on the side wall of the water guide surface, which is close to the water receiving disc, one end of each rib is fixedly connected with the inner wall of the tower body, and the other end of each rib is fixedly connected with the outer wall of the air duct.

Through adopting above-mentioned technical scheme, because the circulation cooling water through first cooling system drips to the water guide surface for a long time for the water guide surface needs to bear great impact force, consequently sets up the rib below the water guide surface, makes the intensity of water guide surface obtain the reinforcing, reduces because of circulating cooling water long-term along the water guide surface drainage, makes the condition emergence that is difficult to firm connection between water guide surface and the tower body.

Optionally, the first branch pipe group comprises a plurality of first branch pipes communicated with the main water supply pipe, the first branch pipes are fixedly connected to the top wall of the tower body, and a plurality of mist spray heads are arranged on the first branch pipes along the length direction;

the second branch pipe group comprises a plurality of second branch pipes communicated with one end, close to the water receiving disc, of the main water supply pipe, the second branch pipes are fixedly connected with the rib, and a plurality of mist spray heads are arranged on each second branch pipe along the length direction.

Through adopting above-mentioned technical scheme, set up a plurality of first minutes pipe and a plurality of second minutes pipe, and first minutes pipe and second minutes pipe are provided with a plurality of vaporific shower nozzles along length direction for spray to the packing ring from first minutes pipe group, or the second minutes pipe sprays the circulating cooling water more evenly dispersed on the packing piece, thereby make first cooling system or second cooling system to the cooling effect of circulating cooling water better.

Optionally, the parallel interval of tower body inner wall is provided with the drainage face, drainage face one end with the lateral wall fixed connection that the wind channel was kept away from to the water guide face, the drainage face other end extends to between second cooling system bottom and the water collector, the drainage face with form the drainage channel that supplies the rivers to drain to the water collector between the tower body inner wall.

Through adopting above-mentioned technical scheme, after the recirculated cooling water drip behind first cooling system cooling to the water guide surface, in the slope drainage to drainage channel along the water guide surface, the recirculated cooling water falls into the water collector downwards along the drainage face in, and the drainage face can separate filler piece and recirculated cooling water for the recirculated cooling water can be more smooth and easy the drip to the water collector in.

Optionally, the packing ring is porous three-dimensional structure, the packing piece includes a plurality of siphunculus, a plurality of siphunculus parallel arrangement, and adjacent two siphunculus lateral wall laminating and fixed connection.

By adopting the technical scheme, as the plurality of auxiliary exhaust fans are arranged on the side wall of the tower body, the plurality of auxiliary exhaust fans are arranged on the top wall of the tower body, and the space between the bottom of the packing ring and the water guide surface is smaller, the air flow direction in the first cooling system is more turbulent, the packing is arranged into a porous three-dimensional structure, so that air in any direction can pass through the packing ring, the contact area between the packing ring of the porous structure and circulating cooling water is larger, and the circulating cooling water can be cooled better;

because a large space exists between the filler block and the water receiving disc, air sucked from the main exhaust fan to the tower body firstly enters the space between the filler block and the water receiving disc and is outwards discharged by the main exhaust fan at the top of the air duct, at the moment, air flow upwards circulates and can upwards circulate along a plurality of through pipes, and therefore the cooling effect on circulating cooling water in the through pipes is realized; in addition, the circulating cooling water can be guided by the plurality of through pipes, so that the circulating cooling water can flow down along the through pipes, and the circulating cooling water can flow more smoothly.

Optionally, the siphunculus is provided with the protrusion along length direction bending setting, and siphunculus inner wall.

By adopting the technical scheme, the protrusion is arranged on the inner wall of the through pipe, so that the contact area between the circulating cooling water and the inner wall of the through pipe is increased, on one hand, the circulating cooling water flow path is increased, the cooling time is prolonged, and the cooling effect is better; on the other hand, more circulating cooling water can be attached to the inner wall of the through pipe, so that the circulating cooling water is cooled when air circulates.

Optionally, one side of the auxiliary exhaust fan and the main exhaust fan, which is close to the inside of the tower body, is provided with a waterproof baffle, the waterproof baffle comprises a plurality of baffle plates which are arranged at intervals in parallel, and the baffle plates and the inner wall of the tower body form an included angle in a range of 10-30 degrees.

Through adopting above-mentioned technical scheme, because vice air exhauster and main air exhauster set up at the tower body lateral wall, the circulating cooling water who drops from first cooling system or second cooling system splashes down to the tower body lateral wall easily, gets into in vice air exhauster or the main air exhauster, causes the damage of vice air exhauster or main air exhauster. The waterproof partition plates are arranged outside the main exhaust fan and the auxiliary exhaust fan, and the plurality of baffle plates are arranged at intervals, and the inclination angle is between 10 degrees and 30 degrees, so that circulating cooling water splashed to the side wall of the cooling tower can be blocked by the baffle plates, and the circulating cooling water is limited to enter the main exhaust fan or the auxiliary exhaust fan; meanwhile, as the baffle plates are arranged at intervals, the main exhaust fan or the auxiliary exhaust fan can smoothly suck external dry and cold air into the cooling tower.

In summary, the present application includes at least one of the following beneficial effects:

1. the first cooling system and the second cooling system are arranged in the cooling tower, and can cool circulating cooling water at the same time, so that the cooling efficiency of the cooling tower is improved;

2. the packing rings and the packing blocks are arranged in different structural forms, so that the first cooling system and the second cooling system can operate more efficiently;

3. the waterproof partition plates are arranged outside the main exhaust fan and the auxiliary exhaust fan, so that the possibility that circulating cooling water enters the main exhaust fan or the auxiliary exhaust fan can be reduced, and the main exhaust fan and the auxiliary exhaust fan are not easy to damage.

Drawings

FIG. 1 is a schematic view showing the overall structure of a cooling tower according to an embodiment of the present application;

FIG. 2 is a schematic view, partially in section, showing the internal drainage of a cooling tower, according to an embodiment of the present application;

FIG. 3 is a schematic view, partially in section, showing the internal structure of a cooling tower according to an embodiment of the present application;

FIG. 4 is a schematic view of a partial structure of a packing block according to an embodiment of the present application;

fig. 5 is a schematic view showing a partial structure of a waterproof separator according to an embodiment of the present application.

Reference numerals illustrate: 1. a tower body; 11. a water receiving tray; 12. a water outlet pipe; 2. a main water supply pipe; 3. a first branch pipe; 31. a mist nozzle; 4. a second branch pipe; 5. a first cooling system; 51. a packing ring; 52. an auxiliary exhaust fan; 53. an auxiliary exhaust fan; 54. a water guiding surface; 55. prismatic bone; 551. a fixing member; 56. a water discharge surface; 57. a drainage channel; 6. a second cooling system; 61. a filler block; 611. a through pipe; 612. a protrusion; 62. a main exhaust fan; 63. a main exhaust fan; 7. an air duct; 8. a waterproof separator; 81. a baffle.

Detailed Description

The application is described in further detail below with reference to fig. 1-5.

Referring to fig. 1, the circular cooling tower disclosed by the embodiment of the application comprises a tower body 1, wherein an air duct 7 is vertically arranged in the center of the tower body 1, and the air duct 7 extends upwards and passes through the tower body 1 to be communicated with the outside. A vertical main water supply pipe 2 is arranged in the air duct 7, and the main water supply pipe 2 is used for discharging circulating cooling water into the cooling tower. The main water supply pipe 2 is communicated with a first branch pipe group and a second branch pipe group, and the first branch pipe group is arranged above the second branch pipe group.

Referring to fig. 2 and 3, the first sub-pipe group includes a plurality of first sub-pipes 3 disposed at intervals along the circumferential side of the main water supply pipe 2, the plurality of first sub-pipes 3 are all communicated with the main water supply pipe 2, and the first sub-pipes 3 are fixed on the top wall of the tower body 1; the second branch pipe group is arranged at the end of the main water supply pipe 2 far away from the outside, the second branch pipe group comprises a plurality of second branch pipes 4 which are arranged at intervals along the end of the main water supply pipe 2, the plurality of second branch pipes 4 are also communicated with the main water supply pipe 2, and the diameter of the main water supply pipe 2 is larger than that of the first branch pipe 3 or the second branch pipe 4. Each of the first branch pipe 3 and the second branch pipe 4 is provided with a plurality of mist spray heads 31 along the length direction thereof, so that the circulating cooling water flowing into the first branch pipe 3 or the second branch pipe 4 can be uniformly dispersed and sprayed into the cooling tower through the mist spray heads 31.

Referring to fig. 2 and 3, a water receiving tray 11 is provided at the bottom of the tower body 1, and an outlet pipe 12 for discharging circulating cooling water in the cooling tower is connected to the bottom of the tower body 1. A first cooling system 5 is arranged between the first branch pipe group and the second branch pipe group, and a second cooling system 6 is arranged between the second branch pipe group and the water receiving disc 11. The first cooling system 5 comprises a packing ring 51 and an auxiliary exhaust group, the inner annular wall of the packing ring 51 is fixedly connected with the side wall of the air duct 7, and the outer annular wall of the packing ring 51 is fixedly connected with the inner wall of the tower body 1, so that circulating cooling water sprayed downwards from the first branch pipe group can be discharged downwards into the water receiving disc 11 after passing through the packing ring 51.

Referring to fig. 1 and 2, the auxiliary exhaust set includes a plurality of auxiliary exhaust fans 52 disposed on a side wall of the tower body 1, and a plurality of auxiliary exhaust fans 53 disposed on a top wall of the tower body 1, wherein the auxiliary exhaust fans 52 are disposed below the packing rings 51, and above the second branch set, the auxiliary exhaust fans 52 can suck dry and cool air into the tower body 1, and by disposing the auxiliary exhaust fans 52 below the packing rings 51, and disposing the auxiliary exhaust fans 53 on the top wall of the tower body 1, an air flow flowing from below the packing rings 51 to above the packing rings 51 can be formed in the tower body 1, wherein the packing rings 51 are of a porous structure, and the porous structure of the packing rings 51 increases the contact area between circulating cooling water and the packing rings 51, and enables the air flow in any direction to pass through the packing rings 51. When the air flow passes through the packing ring 51, the dry and cold air can exchange heat with the circulating cooling water in the packing ring 51, and the air flow takes away the heat in the circulating cooling water and is discharged into the air through the auxiliary exhaust fan 53, so that the cooling effect on the circulating cooling water is realized.

Referring to fig. 2 and 3, a water guide surface 54 is provided between the first cooling system 5 and the second cooling system 6, and the circulating cooling water cooled by the first cooling system 5 drops down from the packing ring 51 onto the water guide surface 54. The water guide surface 54 is annular, the inner annular wall of the water guide surface 54 is fixedly connected with the side wall of the air duct 7, a plurality of rib bones 55 are fixed on the side wall, close to the water receiving disc 11, of the water guide surface 54, one end of each rib bone 55 is fixedly connected with the side wall of the air duct 7, the other end of each rib bone 55 is fixedly connected with the inner wall of the tower body 1, and the rib bones 55 are arranged to enable the rib bones 55 to support the water guide surface 54, so that stability of the water guide surface 54 is enhanced.

Referring to fig. 2 and 3, a drainage surface 56 is fixed on the outer annular wall of the water guiding surface 54, the drainage surface 56 is cylindrical, the drainage surface 56 and the side wall of the tower body 1 are arranged at intervals in parallel, the rib 55 penetrates through the drainage surface 56, one end of the drainage surface 56 is connected with the water guiding surface 54, and the other end extends to a position between the bottom of the second cooling system 6 and the water receiving disc 11, so that a drainage channel 57 is formed between the drainage surface 56 and the inner wall of the tower body 1. The water guide surface 54 is provided with an inclined surface gradually approaching the water receiving tray 11 from the air duct 7 to the inner wall of the tower body 1, and the water guide surface 54 is obliquely arranged, so that the circulating cooling water dripped on the water guide surface 54 can smoothly flow into the drainage channel 57 and be discharged into the water receiving tray 11 from the drainage channel 57.

Referring to fig. 3, the second branch pipe group is disposed on a side of the water guide surface 54 near the water receiving tray 11, and each rib 55 is fixed with a plurality of fixing members 551, and one end of the fixing member 551 away from the rib 55 is fixedly connected with the second branch pipe 4. The fixing piece 551 is provided so that the second tube-dividing group can be fixedly connected with the rib 55, thereby enabling the second tube-dividing group to be kept stable.

Referring to fig. 1 and 3, the second cooling system 6 includes a main exhaust stack and a packing block 61 disposed below the second branch stack, the packing block 61 being spaced from the end of the air duct 7 adjacent to the water pan 11. The main exhaust group comprises a main exhaust fan 62 and a main exhaust fan 63, wherein the main exhaust fan 62 is arranged on the side wall of the tower body 1 between the bottom of the filler block 61 and the water receiving disc 11, and the main exhaust fan 63 is arranged at one end port of the air duct 7 communicated with the outside.

Referring to fig. 3 and 4, the packing block 61 includes a plurality of through pipes 611, the plurality of through pipes 611 are all vertically arranged, each through pipe 611 is bent along the length direction according to the same bending direction and bending curvature, the side walls of any two adjacent through pipes 611 are attached and fixedly connected, and a plurality of protrusions 612 are arranged on the inner wall of the through pipe 611.

Referring to fig. 1 and 3, the circulating cooling water sprayed from the second branch pipe group falls into the filler block 61, and simultaneously the main exhaust fan 62 exhausts air into the tower body 1, so that air flow from bottom to top exists in the filler block 61, dry and cold air passes through the filler block 61 along the through pipe 611, at this time, the circulating cooling water attached to the inner wall of the through pipe 611 can exchange heat with the dry and cold air, so that the circulating cooling water in the filler block 61 is cooled, and is discharged out of the tower body 1 through the air; meanwhile, the cooled circulating cooling water passes through the filler block 61 and then drops into the water pan 11, so that the cooling circulation of the second cooling system 6 is realized. The protrusion 612 is arranged on the inner wall of the through pipe 611, so that the contact area between the circulating cooling water and the inner wall of the through pipe 611 can be increased, the circulating cooling water can be better attached in the through pipe 611, and the cooling effect of the second cooling system 6 on the circulating cooling water is better.

Referring to fig. 1 and 5, a waterproof baffle 8 is arranged inside the main exhaust fan 62 and the auxiliary exhaust fan 52, which are close to the tower body 1, the waterproof baffle 8 comprises a plurality of baffle plates 81, the baffle plates 81 are arranged at intervals in parallel, the baffle plates 81 are fixedly connected with the tower body 1, and an included angle of 10-30 degrees exists between the baffle plates 81 and the side wall of the tower body 1. The waterproof baffle plate 8 is arranged, so that the circulating cooling water falling into the water receiving disc 11 from top to bottom is not easy to splash into the main exhaust fan 62 or the auxiliary exhaust fan 52, and the damage of the main exhaust fan 62 or the auxiliary exhaust fan 52 due to the splashing of the circulating cooling water inside is reduced; meanwhile, the baffle plates 81 are arranged at an included angle and at intervals, so that the outside air can be smoothly introduced into the tower body 1 while the baffle plates 81 can keep water.

The implementation principle of the circular cooling tower provided by the embodiment of the application is as follows: circulating cooling water with heat generated in a production workshop enters the tower body 1 through the main water supply pipe 2, and when the flow rate of the circulating cooling water is large, part of the circulating cooling water enters the first branch pipe group and is uniformly sprayed into the first cooling system 5 through the first branch pipe 3; the other part of circulating cooling water enters the second branch pipe group and is uniformly sprayed into the second cooling system 6 through the second branch pipe 4. The circulating cooling water is cooled simultaneously by the first cooling system 5 and the second cooling system 6 to improve the cooling efficiency of the cooling tower.

In the first cooling system 5, a plurality of auxiliary exhaust fans 52 arranged on the side wall of the tower body 1 are mutually matched with a plurality of auxiliary exhaust fans 53 arranged on the top wall of the tower body 1, so that air in the first cooling system 5 flows, and the flowing air exchanges heat with circulating cooling water in the packing ring 51 to realize cooling of the circulating cooling water. The packing ring 51 is also provided in a porous structure so that air flows in all directions can pass through the packing ring 51 and be discharged from the auxiliary exhaust fan 52.

In the second cooling system 6, because a larger space is formed between the water pan 11 and the filler block 61, the air pumped by the main exhaust fan 62 can firstly enter the space between the water pan 11 and the filler block 61, and then the air in the tower body 1 is pumped by the main exhaust fan 63, so that the dry and cold air in the space can flow upwards along the filler block 61, at this time, the air can flow upwards along the through pipe 611 to the exhaust tower body 1, and the circulating cooling water in the through pipe 611 can be cooled when the air flow flows along the through pipe 611.

The above embodiments are not intended to limit the scope of the present application, so: all equivalent changes in structure, shape and principle of the application should be covered in the scope of protection of the application.

Claims

1. A circular cooling tower, characterized in that: the novel energy-saving tower comprises a tower body (1), wherein a main water supply pipe (2) is arranged in the center of the tower body (1), and a first branch pipe group and a second branch pipe group are communicated with the main water supply pipe (2);

a first cooling system (5) and a second cooling system (6) are further arranged in the tower body (1), the first branch pipe (3) is arranged above the first cooling system (5), the second branch pipe (4) is arranged above the second cooling system (6), and the first cooling system (5) is arranged above the second branch pipe;

the water receiving disc (11) is arranged at the bottom of the tower body (1), the first cooling system (5) and the second cooling system (6) are communicated with the water receiving disc (11), and a water outlet pipeline (12) is communicated with the water receiving disc (11).

2. A circular cooling tower according to claim 1, wherein: an air duct (7) is vertically arranged in the center of the tower body (1), and the main water supply pipe (2) is positioned in the air duct (7);

the first cooling system (5) comprises a packing ring (51) and a secondary exhaust group, and the packing ring (51) is arranged between the outer wall of the air duct (7) and the inner wall of the tower body (1);

the auxiliary exhaust set comprises a plurality of auxiliary exhaust fans (52) arranged on the side wall of the tower body (1) and a plurality of auxiliary exhaust fans (53) arranged on the top wall of the tower body (1).

3. A circular cooling tower according to claim 2, wherein: the second cooling system (6) comprises a main exhaust group and a filler block (61) arranged between the end of the air duct (7) close to the water receiving disc (11) and the water receiving disc (11), and the filler block (61) is fixedly connected with the inner wall of the tower body (1);

the main exhaust group comprises a main exhaust fan (62) arranged at the position, close to the bottom, of the side wall of the tower body (1), and a main exhaust fan (63) arranged at one end, far away from the water receiving disc (11), of the air duct (7).

4. A circular cooling tower according to claim 3, wherein: the packing ring (51) and the second branch pipe group are provided with a water guide surface (54), the water guide surface (54) is annular, the inner annular wall of the water guide surface (54) is fixedly connected with the outer wall of the air duct (7), and the water guide surface (54) is provided with an inclined surface gradually approaching to the water receiving disc (11) from the air duct (7) to the side wall of the tower body (1).

5. A circular cooling tower according to claim 4, wherein: a plurality of ribs (55) are fixed on the side wall of the water guide surface (54) close to the water receiving disc (11), one end of each rib (55) is fixedly connected with the inner wall of the tower body (1), and the other end of each rib is fixedly connected with the outer wall of the air duct (7).

6. A circular cooling tower according to claim 1, wherein: the first branch pipe group comprises a plurality of first branch pipes (3) communicated with the main water supply pipe (2), the first branch pipes (3) are fixedly connected to the top wall of the tower body (1), and a plurality of mist spray heads (31) are arranged on the first branch pipes (3) along the length direction;

the second branch pipe group comprises a plurality of second branch pipes (4) communicated with one end, close to the water receiving disc (11), of the main water supply pipe (2), the second branch pipes (4) are fixedly connected with the rib (55), and a plurality of mist spray heads (31) are arranged on each second branch pipe (4) along the length direction.

7. A circular cooling tower according to claim 4, wherein: the water draining device is characterized in that water draining surfaces (56) are arranged on the inner wall of the tower body (1) at intervals in parallel, one end of each water draining surface (56) is fixedly connected with the side wall of the water guiding surface (54) away from the air duct (7), the other end of each water draining surface (56) extends to the position between the bottom of the second cooling system (6) and the water receiving disc (11), and a water draining channel (57) for water supply and water draining to the water receiving disc (11) is formed between the water draining surfaces (56) and the inner wall of the tower body (1).

8. A circular cooling tower according to claim 3, wherein: the packing ring (51) is of a porous three-dimensional structure, the packing block (61) comprises a plurality of through pipes (611), the through pipes (611) are arranged in parallel, and the side walls of two adjacent through pipes (611) are attached and fixedly connected.

9. A circular cooling tower according to claim 8, wherein: the through pipe (611) is bent along the length direction, and the inner wall of the through pipe (611) is provided with a protrusion (612).

10. A circular cooling tower according to claim 3, wherein: one side of the auxiliary exhaust fan (52) and the main exhaust fan (62) close to the inside of the tower body (1) is provided with a waterproof baffle plate (8), the waterproof baffle plate (8) comprises a plurality of baffle plates (81) which are arranged at intervals in parallel, and the baffle plates (81) and the inner wall of the tower body (1) form an included angle in a range of 10-30 degrees.