CN100520266C - Lower jet type spraying thrust aerating and cooling tower, and jet flow cool wind machine - Google Patents

Abstract

Downspray spray push draft cooling towers and jet coolers. The tower body is equipped with an external rotating spray propulsion and exhaust device that injects hot water under pressure and sprays mist flow. The nozzle sprays downward and the blades draw air downward; The middle and lower part of the tower wall is equipped with wind buckets. There is a multi-layer water spray screen under the spray device, which distributes water and guides the wind to make the water spray evenly, and the cold air passes through the water mist flow for multiple times to fully exchange heat, which greatly improves the heat transfer efficiency. Because the wind and water are in the same direction, the interference of water mist on the wind blades is reduced, the force of the jet flow is increased, and the downward direction of the spray jet flow can also be used, that is, the three airflows of the wind blade mechanical wind, the spray jet wind and the fan jet jet wind are generated. Heat exchange with the spray flow, the air volume is increased, the air-water ratio is above 1.0, which is 29-90% higher than that of the existing upward spray cooling tower, and the temperature drop can be greatly improved. The noise of the water flow in the tower is reduced; the top of the tower does not float; the working water pressure drop is 0.08-0.12MPa. Because the outlet air temperature and outlet water temperature are similar, it can be used as a jet cooler at the same time for cooling and air conditioning in spring, summer and autumn.

Description

Downspray Mist Propel Draft Cooling Towers and Jet Coolers

(1) Technical field:

The invention relates to a spray propulsion ventilation cooling tower and a cooling fan. The cooling tower uses the air in it as the cooling medium, and uses low-pressure hydraulic power to drive the spray to push the atomization device to realize the cooling of the circulating hot water. The cooling fan uses the circulating cold water in the atomization device through the spray as the medium to realize the cooling of the air. All belong to the heat exchange equipment category (F28C) where the medium directly contacts without chemical reaction.

(two) background technology:

The cooling tower is a device that uses hot water and cold air for heat exchange, so that the air is heated and humidified to take away heat and cool the circulating water. The cooling effect depends on the following three factors: ①The air volume of the cooling tower, that is, the air-to-water ratio. ②Mass transfer coefficient, area and time between gas and water. ③The difference between the hot water temperature and the atmospheric wet bulb temperature. Under given environmental conditions (i.e. ③ given water temperature difference) and given mass transfer conditions (i.e. ② given), the cooling effect depends on the air volume of the cooling tower, usually the air volume refers to the air volume discharged from the cooling tower or the air volume on the nameplate of the cooling tower fan, and is determined All the incoming cold air is exhausted after heat exchange. However, it is impossible to conduct heat exchange for all the actual incoming air volume, and a part of the air cannot be effectively utilized. The reasons are as follows: A. The air has the characteristic of flowing to the area with the least resistance. In the packing cooling tower, the air will flow to the area with large gap or no water; in the spray tower, the air will often leave the mist flow in the injection area and flow to the non-fog area. Generally, the injection section is about 300-500mm away from the nozzle outlet. That is to say, there is a short-circuit wind in the current cooling tower. B. The air inlet of the current cooling tower is at the lower part of the tower body, and the air outlet is at the top of the tower. The wind speed of the cooling tower from bottom to top is about 1.5-2.0m/s, while the water film or water droplets in the cooling tower flow down at about 9m/s and above, so that the water film or water droplets will prevent the air from flowing upwards (the phenomenon of fog blocking the wind), and the air will become a backflow and sinking wind. wind.

Chinese patents 'Gravity Backwater Secondary Jet Spray Propelling Ventilation Cooling Tower' (ZL97107721.9) and 'New Gravity Backwater Secondary Jet Spray Propelling Ventilation Cooling Tower' (ZL01299902.X), see Figure 5, the tower body 6n is installed inside Spray type external rotation spray propulsion exhaust device 1n, blade 1.1n upwards to draw air, primary and secondary air inlets are 5n1, 5n2, air outlet 4n is on the top of the tower, spraying device 1n sprays 1.3n from bottom to top and heats up with the inlet air The exchanged cooling water drops in the water return tank 3n, falls into the bottom secondary injection pipe 8n through the gravity tube 2n, sprays up again through the secondary nozzle 7n, and finally the cold water falls into the water storage tank 9n. Spraying is used to enhance the gas-water mass transfer effect, jet fans are used to replace electric fans, and gravity return water is used for secondary spraying to overcome backflow sinking wind. But there are still following problems: A. The structure of the secondary spraying system is complicated, the cost rises, and the market competitiveness declines. B. There is still short-circuit wind, and the heat exchange is not sufficient. C. The phenomenon of fog blocking the wind still exists, which reduces the wind speed at the air outlet on the top of the tower. If the wind speed at the top of the tower is increased, it will cause fog on the top of the tower. D. The air outlet area is smaller than the air inlet area, and the air flow out of the tower is insufficient. E. The height of the spray device in the tower must be greater than 3 meters, resulting in an increase in the height of the tower and an increase in cost.

(3) Contents of the invention:

The down-spray spray propulsion ventilation cooling tower and the jet cooling fan proposed by the present invention solve the influence of short-circuit wind and fog blocking wind on the heat exchange effect existing in the existing "jet spray propulsion ventilation cooling tower", reduce energy consumption, and at the same time Solve the problems of floating water on the top of the tower, complex structure, and loud noise.

Its technical scheme is as follows:

Downspray spray propulsion ventilation cooling tower, including tower body, air inlet and air outlet, an external rotating spray propulsion exhaust device connected to the water inlet pipe is installed in the tower body, the bottom of the tower body is a water storage tank connected to the water outlet pipe, and the external A water pump is installed in the water inlet pipeline, which is characterized by:

A. The top of the tower is provided with a primary air inlet tube 2, and the entrance of the primary air intake tube is a primary air inlet tube 2a; the outer periphery of the primary air intake tube is provided with a secondary air intake tube 3, and the entrance of the secondary air intake tube is a secondary air inlet tube 3a The air outlet is located in the middle and lower part of the tower body; the side wall of the tower body is fully opened, and an air bucket is installed around the outer circumference of the air outlet; hot water is in the water inlet pipe, and cold water is in the water storage tank and outlet pipe; B. External rotation Type spray propulsion exhaust device 1 is installed in the primary air inlet tube, using downward spraying nozzles and downward draft fan blades; C. Below the external rotation spray propulsion exhaust device, three or more layers of water are installed on the height of the tower body The screen, the same layer and the space between layers are air ducts, and its structure is as follows: ①The inner circumference of the water spray screen is circular, and the outer circumference is round or square; Even-numbered screens are large-diameter screens, and the diameter of the inner hole of the large-diameter screen is larger than the outer diameter of the adjacent small-diameter screen below; ③ There can be one or two large-diameter screens in the same layer, and the outermost edge is the same The tower wall is sealed; ④ The outer diameter of the first layer of screen is smaller than the distance D1 between the two opposing nozzles; ⑤ The diameter of the inner hole of the last layer is larger than the inner diameter of the primary air inlet tube D2. Therefore, the water distribution and wind guide of each layer of the water spraying screen make the water spraying uniform, and the cold wind passes through the water mist flow for many times.

The lower part of the above-mentioned tower body is equipped with three or more injection swirl atomizing nozzles (patent number ZL89104110, 9) connected to the water inlet pipe for water flow regulation. When the flow meets the design requirements, the injection swirl The flow atomizing nozzle can be canceled without installation. The area of the air outlet is larger than that of the air inlet. The above-mentioned tower body is a square body or a circular body. The patent No. ZL00112630.X of the above-mentioned external rotation type spray propulsion exhaust device (hereinafter referred to as the spray device 1).

The jet-flow cooler has mostly the same structure as the above-mentioned downspray spray propulsion ventilation cooling tower, except for the following differences: ①The area of the air outlet is 1/5 to 1/2 of the full opening area of the side wall of the tower body. ②The wind guide bucket and air supply pipe are installed at the air outlet. ③The refrigerant water is in the water inlet pipe, and the hot water is in the water storage tank and outlet pipe.

Beneficial effects of the present invention:

i. The spray device in the cooling tower was originally sprayed upwards, and the fan blades were drawn upwards. The present invention changes nozzle to spray downwards, and fan blade is also to draft downwards. In this way, the influence of the fog generated by the upper spray on the heat exchange effect is solved. The spray thrust is increased (the horizontal installation angle β of the nozzle 1.1 can also be reduced to increase the thrust as shown in Figure 3); the interference of water mist on the fan blade suction is reduced, and the wind force of the jet fan is significantly increased; plus the downward spray flow The ejection wind can also be utilized, so there are three airflows in the cooling tower: the fan mechanical wind, the spray ejection wind and the fan ejection air for heat exchange, and the air volume increases, that is, the air-water ratio is increased to more than 1.0, which is higher than the existing one. The spray cooling tower is 29-90% higher, so the temperature drop of the cooling tower can be greatly improved. ii. Using multi-layer water spraying screen, the water distribution is uniform, the cold air passes through the water mist flow for many times, the air-water exchange time is long, the heat transfer condition is improved, and the temperature drop is improved; and the structure is simple, the cost is low, the service life is long and Easy to install and maintain. iii. Due to the improvement of air volume and air-water mass transfer conditions, the working water pressure of the cooling tower water pump is reduced from the originally required 0.12-0.19MPa to 0.08-0.12MPa, saving 29-90% of the electric power of the water pump. iv. Due to the downward spray and deceleration through multi-layer screens, the problem of mist in the spray tower is solved. v. Solve the noise caused by water droplets falling back and hitting the wall. vi, the diameter of the nozzle is increased, which can be used for sewage and expand the market share. vii. Solved the excessive air resistance caused by the outlet area being smaller than the inlet area. viii. The wind and water flow in the same direction and horizontally, and the temperature of the air outlet and the water outlet are similar. The cooling tower can be used as a cooling fan for cooling in spring, summer and autumn.

(4) Description of drawings:

Figure 1 Structural diagram of downspray spray propulsion draft cooling tower

Figure 2 Structural Diagram of Jet Air Cooler

Fig. 3 Structural diagram of external rotation spray propulsion exhaust device 1 (spraying downwards, drawing downwards)

Fig. 4 Structural diagram of injection swirl atomizing nozzle 8

Figure 5 Schematic Diagram of the Existing ‘New Gravity Backwater Secondary Jet Spray Propulsion Ventilation Cooling Tower’

(5) Specific implementation methods:

Embodiment 1: see Fig. 1, Fig. 3, Fig. 4

As shown in Fig. 1, the downspray spray propulsion ventilation cooling tower is composed as follows: the top of the tower body 6 is provided with a primary air inlet 2, where a primary air inlet 2a is formed; a secondary air inlet 3 is arranged on the outer periphery, where a secondary air inlet 3a is formed . The side wall of the middle and lower part of the tower body is fully opened with an air outlet, where an air bucket 9 with a water accumulation function is installed to form an air outlet 9a. When the tower body is a tetrahedron, the wind bucket is a four-sided inverted trapezoid; when the tower body is a cylinder, the wind bucket is an inverted cone. The area of the air outlet 9a is greater than the sum of the areas of the air inlets 2a and 3a. The tower body 6 is welded together by a plurality of supporting steel pipes or water pipes, the tower wall is formed by sealing the tower plate 6.1, and a support member 12 is arranged under the tower body. The spray device 1 is installed in the primary air inlet tube 2, and a vertical water inlet pipe 7 is arranged in the center of the tower body, extending upward from the bottom of the tower to the lower part of the primary air inlet tube 2, and the bottom of the spray device 1 communicates with the top port of the water inlet pipe 7 and The bottom of the tower is fixedly supported by the water inlet pipe, and supported on the ground by the outer water pipe 7a.

As shown in Figure 3, the spray device 1 is provided with a hollow rotating water chamber 1.3 and two or more rotating atomizing nozzles 1.1 for downward spraying on the outer surface, and two or more nozzles are fixed on the rotating water chamber above the nozzles. There are four nozzles 1.1 and four fan blades 1.2 for downward drafting; the center is provided with a static liquid inlet mechanism 1.4 connected to the waterway of the rotating water chamber and the atomizing nozzle, and the gap between the liquid inlet mechanism and the rotating water chamber Install the upper and lower water bearing 1.5 and set the axial water hole 1.6, the limit friction ring 1.7 and the gland 1.8, etc. The spray device 1 is connected with the flange 7.1 of the water inlet pipe 7 through the static lower flange 1.41 of the liquid inlet mechanism.

See Fig. 1, four layers of water spraying screens 4 (hereinafter briefly referred to as screens) and the air duct 5 therebetween are set below the spraying device 1 as follows: 1. The first layer is a small diameter screen 4.1 whose outer diameter is smaller than the relative two nozzles 1.1 Distance D1 (D1 see Figure 3). ②The second layer is two large-diameter screens: the inner diameter of the screen 4.21 is slightly larger than the outer diameter of the third layer of small-diameter screen 4.3, and its center is a circular air duct 5.21; the inner diameter of the outer screen 4.22 is larger than that of the screen The outer diameter of the net 4.21, the radial space between the two is an annular air duct 5.22, and the outer circumference of the screen 4.22 is a circle or a square that matches the shape of the tower wall, and is sealed with the tower wall. ③ The third layer is a small-diameter screen 4.3, and the inner hole is the central air duct 5.3. ④ The diameter of the inner hole of the fourth layer of screen 4.4 is larger than the inner diameter D2 of the primary air inlet tube 2, and the inner hole is the central air duct 5.4; the outer circumference of the screen 4.4 is a circle or square that matches the shape of the tower wall, and is sealed with the tower wall , The screen 4.4 is placed on the bottom plate 6.2 of the tower body.

As shown in Fig. 4, the structure of the injection swirl atomizing nozzle 8 is as follows (hereinafter referred to as the upper spray nozzle 8): the pressure water enters the swirl chamber 8.2 from the liquid inlet pipe 8.1, and the air enters from the multi-stage series ring suction channel 8.3 And nozzle 8.4 lead into, form atomized jet flow in multi-stage mixing chamber 8.5 and spray out from top diffuse flow cone 8.6 and spray liquid through hole 8.7. This is a low pressure high flow nozzle. In this patent, it is used to adjust the flow rate of the above-mentioned spray device 1 . The water inlet pipe 8a communicated with the upper spray nozzle 8 is installed on the liquid surface of the water storage tank 10, and is communicated with the vertical water inlet pipe 7 with a flange.

Working process: The low-pressure hot water 7b from the water pump enters the cooling tower from the water pipe 7a at the bottom of the tower body, and is sent to the spray device 1 through the central vertical water inlet pipe 7 and sent to the upper spray nozzle 8 through the water inlet pipe 8a. As shown in Figure 3, the low-pressure hot water 1b enters the spray device 1, passes through the central channel of the liquid inlet mechanism 1.4, and enters the spray head 1.1 under the action of centrifugal force to spray downward, and the spray flow reversely pushes the spray head 1.1 and the rotating water chamber 1.3 to rotate and drive The integrated blade 1.2 rotates to form a rotating spray 1a that sprays obliquely downward. See Fig. 1 and Fig. 3, according to the difference of water pressure, choose the appropriate nozzle 1.1 installation angle β to make most of the water mist fall into the state of the water spray screen 4.21. At the same time, the fan blade draws air downwards, which generally can ensure that the wind speed entering the primary air inlet tube 2 is more than 10m/s. Since the primary air inlet tube 2 has a high air outlet speed and has an ejection effect, a secondary air inlet tube 3 is arranged on the outside, and a secondary air inlet channel 3a is formed between the two air tubes, so that the ejected wind enters the tower. The rotating spray is forced to evaporate under the action of the primary wind and the secondary wind, and the vapor pressure of the evaporated water is the saturated water vapor pressure of the hot water. For example: the inlet water temperature is 40°C, and the corresponding saturated water vapor pressure is 7.33kpa. This pressure is greater than the ambient atmospheric pressure of 100kpa. The pressure difference between the two makes the external air convect at a high speed to the water vapor evaporation area in the tower. The convection velocity is about 190m/s, and the air flow forms a negative pressure vacuum of about 22kpa. Thus, the high-speed convection strengthens the evaporation of water mist, and the vacuum increases the air intake of the tower.

Most of the rotating spray 1b of the downward spray from the spraying device 1 falls into the screen cloth 4.21, and the rest falls into the screen cloth 4.1 and 4.22, and becomes fine water droplets after deceleration and falls again. After the screen cloth 4.1 water drop falls into the screen cloth 4.3, it directly falls into the sump tank 10 at the bottom of the tower. The water droplets of screen cloth 4.21 and 4.22 partly fall into screen cloth 4.4, and another part falls into the water accumulation tank at the bottom of the tower through air duct 5.4 or falls into the water accumulation tank after colliding with the spray flow on the upper spray nozzle 8. The cooling water in the water storage tank is sent to the user through the water outlet pipe 11.

The primary air and the secondary air-cooled air flow into the tower first pass through the spray device 1 spray flow to force heat exchange to increase heat and humidify, and then flow through the circular air duct 5.21 and the annular air duct 5.22. The area of the annular air duct is larger than the circular air duct during design. Road, most of the airflow flows into the annular air duct 5.22 like this, and a small part flows into the circular air duct 5.21. The air flow through the air duct 5.22 passes through the screen 4.3 and enters the air duct 5.4. Simultaneously, the air flow of the air duct 5.21 turns to the water droplets falling from the screen cloth 4.21 under the blocking of the screen cloth 4.3, and the two flow into the air duct 5.4 after heat exchange. The air flow at the lower part of the air duct 5.4 exchanges heat with the water droplets at the lower part of the screen 4.4 and the spray on the nozzle 8 again, and finally flows into the atmosphere from the air outlet 9a of the wind bucket 9 under the influence of the wind pressure and the falling of the water droplets. Because the water in the tower and the wind flow in the same direction and laterally, the outlet air temperature is close to the outlet water temperature, so the outlet air is not hot air but slightly higher than the outlet water temperature and lower than the atmospheric dry bulb temperature.

Example 2: Jet Cooler

See Fig. 2, except that the structure of the downspray type spray propelling ventilation cooling tower of Embodiment 1 is all the same except for the following, the difference: 1. if the tower body 9 is a square, the area of the air outlet is the area of the fully open air outlet on the side wall of the tower body 1/4, that is, the tower wall is sealed on three sides, and only one side is equipped with wind bucket 9. 2. install the air delivery pipe 13 on the air funnel. ③The water inlet pipe 7 is refrigerant water (7-20° C.), the air intake is hot and humid wind, and the air outlet is cold and wet wind. The raised hot water is in the sump tank and the water outlet pipe.

Claims (8)

1. following spray atomizing propulsion aeration cooling tower, comprise tower body (6), air inlet and air outlet, in tower body, install the external rotation type spray-driven exhausting equipment (1), the water storage tank (10) of tower body bottom that are communicated with water inlet pipe (7) for linking to each other with outlet pipe (11), establish water pump in the outside inlet pipeline, it is characterized in that:

A. an air intake tube (2) is established at the tower body top, and an air intake tube porch is an air inlet (2a); One time air intake tube periphery is established secondary air tube (3), and secondary air tube porch is secondary air mouth (3a); Air outlet is located at the tower body middle and lower part; Adopt tower body sidewall standard-sized sheet air port, around air port periphery dress wind scoop (9); In the water inlet pipe (7) is hot water, is cold water in water storage tank and the outlet pipe;

B. external rotation type spray-driven exhausting equipment (1) is contained in the air intake tube (2), adopts the shower nozzle (1.1) of spraying downwards and the fan blade (1.2) of downward exhausting;

C. three layers and above trickle screen cloth (4) are established in the external rotation type spray-driven exhausting equipment below on the tower body height, are air channel (5) with layer and interlayer space, and its structure is as follows: 1. week is circular in the trickle screen cloth, and periphery is circular or square; 2. the screen cloth of each odd-level (4.1,4.3) is the minor diameter screen cloth, and the adjacent even level screen cloth (4.2,4.4) in below is the major diameter screen cloth, and major diameter screen cloth diameter of bore is greater than below adjacent minor diameter screen cloth external diameter; 3. the major diameter screen cloth with one deck is 1 or 2, and outermost edge and the sealing of tower wall; 4. ground floor screen cloth (4.1) external diameter is less than relative two shower nozzles (1.1) space D 1; 5. the diameter of bore of the last layer is greater than an air intake tube inside diameter D 2.

2. by the described cooling tower of claim 1, it is characterized in that the below installing is communicated with water inlet pipe in the tower body 3 and above induced jet type swirling-flow atomizing nozzle (8).

3. by the described cooling tower of claim 1, it is characterized in that tower body is square body or round.

4. by the described cooling tower of claim 1, it is characterized in that the air outlet area greater than once with secondary air open area sum.

5. jetting flow blower fan, comprise tower body (6), air inlet and air outlet, in tower body, install the external rotation type spray-driven exhausting equipment (1), the water storage tank (10) of tower body bottom that are communicated with water inlet pipe (7) for linking to each other with outlet pipe (11), establish water pump in the outside inlet pipeline, it is characterized in that:

A. an air intake tube (2) is established at the tower body top, and an air intake tube porch is an air inlet (2a); One time air intake tube periphery is established secondary air tube (3), and secondary air tube porch is secondary air mouth (3a); Air outlet is located at the tower body middle and lower part; The air outlet area is 1/5～1/2 of a tower body sidewall standard-sized sheet open area, and is adorning wind scoop (9) and ajutage (13) around the air port periphery; In the water inlet pipe is chilled water, is hot water in water storage tank and the outlet pipe;

B. external rotation type spray-driven exhausting equipment (1) is placed in the air intake tube (2), adopts the shower nozzle (1.1) of spraying downwards and the fan blade (1.2) of downward exhausting;

C. three layers and above trickle screen cloth (4) are established in the external rotation type spray-driven exhausting equipment below on the tower body height, and reaching with layer and interlayer space is air channel (5), and its structure is as follows: 1. week is circular in the trickle screen cloth, and periphery is a circle or square; 2. the screen cloth of each odd-level (4.1,4.3) is the minor diameter screen cloth, and the adjacent even level screen cloth (4.2,4.4) in below is the major diameter screen cloth, and major diameter screen cloth diameter of bore is greater than below adjacent minor diameter screen cloth external diameter; 3. the major diameter screen cloth with one deck is 1 or 2, and outermost edge and the sealing of tower wall; 4. ground floor screen cloth (4.1) external diameter is less than relative two shower nozzles (1.1) space D ₁5. the diameter of bore of the last layer should be greater than an air intake tube inside diameter D ₂

6. by the described air-cooler of claim 5, it is characterized in that the below installing is communicated with water inlet pipe in the tower body 3 and above induced jet type swirling-flow atomizing nozzle (8).

7. by the described air-cooler of claim 5, it is characterized in that tower body is square body or round.

8. by the described cooling tower of claim 5, it is characterized in that the air outlet area greater than once with secondary air open area sum.

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