CN208520228U - Gravity water return secondary spray cooling tower - Google Patents

Abstract

Gravity water return secondary spray cooling tower, has tower body, appearance to have column plate, secondary air inlet, shutter；There are water storage tank, water outlet, water inlet component in lower section；There are sieve air duct, water collection device in top.There are return flume and gravity water return pipe in tower.The utility model is improved for existing issue, and repetition test provides: N1 spray heads and one, center spraying device injection flow ratio K are taken as 2-3 times in tower.And provide sprinkler height and installation direction.Return flume simplifies, and only sets and installs rectangular return flume along inner wall of tower.First and second spray head bore is big, and pressure is low, nonclogging secondary injection rotational flow atomized spray injector.Eliminate the dripping water screen of easy choke.Result: hydraulic pressure 0.12MPa is surveyed in examination, and at 26 DEG C of wet-bulb temperature, 42 DEG C of hot water is down to 32 DEG C by this tower, and 37 DEG C are down to 29 DEG C, and cooling effect is excellent.Have that hydraulic pressure is low simultaneously, noise is small, it is energy saving, be not easy to plug, be reliable for operation, and belong to non-filling, Blower-free forced draught cooling tower may replace existing mechanical draft tower and spray tower.Can generating unit tower and increase water combined column, and realize standardization.

Description

Gravity water return secondary spray cooling tower

One technical field: gravity water return secondary spray cooling tower, belong to non-filling in cooling tower, external unregulated power blower it is strong Aerating and cooling tower processed, i.e. heat exchange medium directly contact the heat-exchange apparatus class (F28C) of not chemically reactive.

Two technical backgrounds

Cooling tower is many widely used circulating water equipment of department in national economy, and the quality of performance is greatly The benefit of influence system, especially among the water resources crisis of today and environmentally friendly crisis, not only to the improvement of cooling tower technology With economic benefit, and there is great social benefit.

Existing cooling tower working principle is to evaporate hot water using cold wind and hot water heat and mass, and air humidification takes away heat Make circulating water cooling.By this principle, circulating water to be made both had needed the wind of sufficient amount, i.e., sufficiently large gas-water ratio makes again There are sufficiently large mass tranfer coefficient and mass transfer area between air and water.In order to increase gas-water ratio, existing cooling tower uses additional wind The mode forced ventilation of machine, or build tall and big double-curve cooling column natural air exhaust.In order to strengthen mass transfer, set in existing cooling tower It sets filler and increases the mass transfer area and mass tranfer coefficient of air water, or increase mass tranfer coefficient and mass transfer area by the way of spraying.

Existing national standards regulation, when the wet-bulb temperature of atmosphere is 28 DEG C, the inflow temperature of cooling tower is 37 DEG C, water outlet Low temperature is 32 DEG C, 5 DEG C of temperature drop.Analysis and practice point out, for reach gas-water ratio that this requires cooling tower should 0.8 or more, or Person says that cooling 1kg water needs the air of 0.8kg.The blower of usual cooling tower is chosen by this requirement.But actually since filler hinders The gas-water ratio of the presence of power, actual motion is much smaller than design value, so not dropping temperature.Filler easily blocks, and deformation, resistance is big, with And the not region flowing of water, cause air water short-circuit.And fan noise is big and the water flow that flows downward prevents cold wind to filler The phenomenon that flowing.It is poor that filler has lacked mass transfer, and the more blockings of filler, this is the contradiction that packed tower is difficult to go beyond.Occur newly opening thus The spray cooling tower of hair.

Existing spray cooling tower the problem is that: 1) spray head gas-water ratio is inadequate.2) the high 0.25- of work water pressure 0.30MPA.3) (operating) water nozzle bore is small, easily clogs.4) existing blower adds the upper spray flow of the spray cooling tower of spray head there are water mists The reflux under the wind formed when whereabouts prevents hot wind from being discharged, and cooling effect is counter to be not so good as packed tower.

<gravity water return secondary spray cooling tower>(ZL971077215) this patent is disclosed within Chinese invention patent 1997 to mention The spraying concept of gravity water return secondary, principle, function are gone out.But the problem is that: 1) only using spraying device as cooling element, Fail that upper spray flow is overcome to fall the reflux under the wind generated after rise, exhaust is obstructed, and gas-water ratio is little, and temperature drop is undesirable.2) spraying device Rotating mechanism be that the ball bearing service life is insufficient, it is difficult to repair, poor reliability, it is difficult to promote and apply.

For the defect of above-mentioned patent, Chinese patent " novel gravity water return secondary spraying aerating and cooling tower " (ZL01256902) it is improved.Improvements are: 1) spraying device of former ball bearing being changed to Chinese patent < evolute The spraying device of spraying heap its interior liquid suspension submerged bearing provided into extractor fan > (patent No. 00112630X).2) by cooling tower Chimney fan be changed to sieve air duct and cool down moisture film again on sieve.3) it is arranged simultaneously in cooling tower primary and secondary spraying Atomizer.4) it is opened up in tower wall and sets secondary air inlet.5) with the spraying device at center on cooling flow (inflow) Based on, supplemented by the primary atomization spray head of surrounding.6) water drenching sieve is provided in the outside of the interior air duct of installation spraying device.

To the above-mentioned cooling tower improved, through in operation, it was found that following problem: 1) based on the spraying device flow of center Cooling tower excessively give design, installation, maintenance to bring difficulty because of the quantity of the spraying device in enlargement.2) center fills by spraying Set flow it is excessive there may be reflux under the wind be allowed to cool exhaust it is unsmooth, influence cooling effect.3) in the list for being greater than 150T/h The water accumulating volume of return flume is insufficient in first cooling tower, thus fails to give full play to secondary spraying cooling effect.4) water drenching sieve shadow The height of secondary spray flow has been rung, thus has influenced cooling effect, while the easy fouling of sieve, has been blocked, deformation.

Three summary of the invention

The utility model proposes gravity water return secondary spray cooling tower, seek to solve existing for above-mentioned existing cooling tower Central backflow under the wind is big, and cooling effect is poor；Center spraying device enlargement quantity is more, and design, installation, maintenance are difficult；Return water Slot water accumulating volume is insufficient, and secondary injection cooling effect fails to give full play to；Water drenching sieve influences cooling effect, and easy fouling, blocking The problems such as.

Technical solution is as follows:

Gravity water return secondary spray cooling tower, comprising: A) tower body 5, tower body outer surface is column plate 9 from top to bottom, it is secondary into Air port 10, shutter 11；Water storage tank 2, water outlet 12 are set below shutter；Tower body lower central has the water inlet group containing water inlet pipe 1 Part.B) a upper spraying type atomising device 13 is arranged in center in tower body；Height is above shutter horizontal plane, in ventilating duct 14 It is interior, and be placed on the water inlet vertical tube 1.1 being connected to water inlet pipe.It is filled on the annular conduit 1a being connected to water inlet pipe on the outside of ventilating duct It is distributed a spray head 4b of N1 branch；A sieve air duct 7 is set above ventilating duct, there is water collection device in sieve air duct upper end.C) in tower Sieve air duct has return flume, gravity water return pipe, the secondary spray head 4a of the N2 branch equipped with distribution on lower horizontal return pipe.Its It is characterized in

1) pressure hot water point that a spray head 4b and a upper spraying type atomising device 13 provide is propped up to N1 by water inlet component It is K with flow-rate ratio, K=N1 branch capacity of sprinkler/mono- device flow=2-3 times is taken in design, pressure hot water pressure is 0.10- 0.20MPa, spray head total number N1≤16.2) return flume is the rectangular return flume 6 of a ring-type along tower body inner wall surrounding, It is sealed between rectangular return flume and tower wall.Rectangular return flume opens four discharge orifice 6a at four angles, and lower section sets four vertical weights at this Power return pipe 3a, four gravity water return tube bottom ends are connected to two groups of symmetrically uniformly distributed annular horizontal return pipe 3b, what 3c was distributed thereon Secondary spray head 4a total quantity N2≤24.3) spray head and secondary spray head installation direction be it is oblique upward, a spray head court To for along the direction that the tower wall surrounding of return flume is sprayed.4) h1=1.0-1.5 meters of height difference away from rectangular return flume of a spray head 4b, Height difference h2≤2.5 meter of the secondary spray head 4a away from rectangular return flume.

The upper spraying type atomising device 13 of liquid suspension submerged bearing can be used in above-mentioned upper spraying type atomising device 13；It can be seen that China is specially Benefit:<external rotation type spray-driven exhausting equipment>patent No. 00112630X.An above-mentioned spray head and secondary spray head can use two simultaneously Secondary injection rotational flow atomized spray injector 4A uses Chinese patent<multiple induced jet type swirling-flow atomizing nozzle>(patent No. simultaneously 891041109).Wherein<secondary injection rotational flow atomized spray injector 4A>is described in detail later in connection with attached drawing.

Above-mentioned<gravity water return secondary spray cooling tower>is known as unit tower, can be combined into combination using N≤2 unit tower Formula cooling tower is described in detail again below in conjunction with attached drawing.

The utility model has the beneficial effects that

1) the utility model it is above-mentioned it is existing aiming at the problem that, to spraying device, atomization, the performance of spray head and its mutual shadow Ring and carried out a large amount of experiment and multiple improvement, gas-water ratio needed for realizing and ensure that circulating water, mass tranfer coefficient and Mass transfer area.2) K=2-3 times of the utility model design discharge distribution ratio, i.e., based on a capacity of sprinkler, device flow is Auxiliary gravity water return scheme both ensure that and cool back since cooling hot water overwhelming majority flow sprays to return flume by a spray head The overwhelming majority of water, which does not generate under the wind reflux, makes effective gas to significantly reduce the vapour lock that water flow generates in cooling tower For water than increasing, steam partial pressure decline is conducive to the evaporation of hot water.So that hot water is cooled down twice again simultaneously, kills two birds with one stone.Operation examination It surveys as a result, working as work water pressure is 0.12MPa, when atmosphere wet-bulb temperature is 26 DEG C, 42 DEG C of hot water can be down to 32 DEG C by Ben Ta, 37 DEG C are down to 29 DEG C.Obtain excellent cooling effect.3) primary, secondary spray head uses secondary injection rotational flow atomized spray injector 4A, because Its interior (operating) water nozzle is hollow one expansion type nozzle of receipts, and aperture is φ 12- φ 18mm, has bore big, pressure is low, is not easy to plug Advantage, and then make the good operating stability of tower, maintenance workload is minimum.4) being sprayed using liquid suspension submerged bearing of spraying device 13 Device, in practice it has proved that need not overhaul for such device continuously-running 2 years or more.5) unit tower structure and moving component simplify: first Existing water drenching sieve is first eliminated, not only reduce ventilation resistance and simplify structure, and prevent sieve fouling, blocking etc..Its Two, return flume 6 is also added the rectangular return flume of the outer periphery inner wall of tower of connection by pervious annular return flume, is now reduced to only set Along the rectangular return flume of inner wall of tower.6) optimization unit tower is not only provided, and makes the combined column to match, is increased with this cold But water simplifies the structure of tower, realizes design cell, standardization.7) there is excellent cooling effect in view of the utility model, and Non-filling, Blower-free are forced down with working water, and noise is small, energy conservation, and nozzle is not easy to plug, a little repair, reliable for operation etc. one Number of advantages, therefore the utility model patent may replace existing mechanical draft tower and spray tower.

Four Detailed description of the inventions

(left side is cross-sectional view to 1 unit tower front view of Fig. 1 embodiment (face Z-X), and right side is outline drawing.)

Fig. 2 is A-A cross sectional plan view (X-Y plane) in Fig. 1.Can overlook spraying device 13,14, spray head 4b of ventilating duct, Rectangular return flume 6,7 following peripheral of sieve air duct etc..Sieve air duct 7 is as shown in dotted line.

Fig. 3 is B-B cross sectional plan view (X-Y plane) in Fig. 1.Secondary spray head 4a, horizontal return pipe 3b, 3C etc. can be overlooked.

The positive view of Fig. 4 secondary injection rotational flow atomized spray injector 4A.

2 modular cooling tower schematic elevation view of Fig. 5 embodiment (cut away left side view, right side outline drawing).

Fig. 6 is A-A cross sectional plan view (X-Y plane) in Fig. 5.

Five specific embodiments

Embodiment 1: unit tower is shown in Fig. 1-Fig. 4

Part identical with existing structure includes the following:

A) see Fig. 1, Fig. 2, tower body 5, plan shape is square.5 tower wall outer surface of tower body is strip column plate from top to bottom 9, secondary air inlet 10, shutter 11.The lower part of shutter sets cooling water water storage tank 2, sets out water pipe 12 thereon.In below tower body The heart is water inlet component, is welded by seamless steel pipe, includes: the water inlet pipe 1 of lowest part, and upper end flange and upper spraying type are spraying The water inlet vertical tube 1.1 of 13 water inlet of device connection；Garden cylindricality reservoir chamber 1.2 is installed in water inlet vertical tube, it is oblique by circumferential four Sparge pipe 1.3 props up a spray head 4b with annular conduit 1a above and distribution N1 and is connected to.B) see Fig. 1, center setting one in tower body Platform upper spraying type atomising device 13；Height in ventilating duct 14, and is placed on into water vertical tube 1.1 above shutter horizontal plane On.A spray head 4b equipped with distribution N1 branch on the annular conduit 1a being connected to water inlet pipe on the outside of ventilating duct；Above ventilating duct If a sieve air duct 7, sieve air duct upper end sets inside and outside water collection device 8b, 8a simultaneously.C) sieve air duct has return water in tower Slot, gravity water return pipe, the secondary spray head 4a of the N2 branch equipped with distribution on lower horizontal return pipe.

It is as follows that 1 unit tower of the present embodiment newly designs part:

1) see Fig. 1, distribution N1 is housed on Fig. 2, the annular conduit 1a in 14 outside of ventilating duct and props up a spray head 4b, water inlet group A spray head 4b is propped up with annular conduit 1a and N1 above by four oblique sparge pipes 1.3 in part, and offer pressure hot water is provided； Water inlet component provides pressure hot water to an atomising device 13 by water inlet vertical tube 1.1.N1 is propped up to be sprayed on a spray head 4b and a platform It is K that type atomising device, which distributes flow-rate ratio, and K=N1 branch capacity of sprinkler/mono- device flow=2-3 times, pressure hot water are taken in design Pressure is 0.10-0.20MPa.See Fig. 2, a spray head 4b total number N1=22 branch is evenly arranged on quadrangle four root canals.

2) see that Fig. 1, Fig. 2, Fig. 3, return flume 6 are located at 7 lower section of sieve air duct, be along the rectangular time cyclic annular of tower body inner wall surrounding Sink 6 has sealing 6b water-tight between rectangular return flume and tower wall.Rectangular return flume opens four discharge orifice 6a, lower section at four angles If four vertical gravity return pipe 3a, the gravity water return bottom end pipe 3a is connected to two symmetrically uniformly distributed annular horizontal return pipe 3b, 3c.See Fig. 3, two annular horizontal return pipe 3b, 3c arranged crosswises, the uniformly distributed N2 of dress altogether props up secondary spray head 4a thereon；N2=40 branch.

3) see spray head 4b of Fig. 1 and secondary spray head 4a installation direction be it is oblique upward, and the side spraying to tower wall surrounding To.Secondary spray head generally can be taken as to central-injection it is oblique upwardly-directed.

4) see Fig. 1, height difference h1 of the spray head 4b of the present embodiment away from rectangular return flume are as follows: 1.5 meters > h1 > 1.2 meter.It is secondary Height difference of the spray head 4a away from rectangular return flume is h2 > 3.0 meter.

5) above-mentioned upper spraying type atomising device 13 uses the upper spraying type atomising device 13 of liquid suspension submerged bearing.It can be seen that China is specially Benefit:<evolute is sprayed heap into extractor fan>patent No. 00112630X..I will not elaborate.

6) the present embodiment above-mentioned spray head 4b and secondary spray head 4a uses secondary injection rotational flow atomized spray injector 4A simultaneously.Its <secondary injection rotational flow atomized spray injector 4A>structure is as follows: seeing Fig. 4, Fig. 1.

Place outside receipts-expansion type (operating) water nozzle 4.2 have air inlet 4.7 injection of cylinder cover 4.3, be provided with into The cylindrical secondary injection set 4.5 of stomata 4.6；In the outer air inlet rectification set 4.4 equipped with cone-shaped inner hole of an injection set, thus The component of formation, sealing are fixed on 4.1 top of hollow ball shape spin chamber of aperture；Spin chamber passes through tangential water pipe 4.9, flange 4.8 are connected to offer pressure hot water with two annular return duct 3b, 3c of the annular conduit 1a or secondary injection that once spray.

Its course of work is as follows:

See Fig. 1, the upper spraying type atomising device 13 and N1 branch that pressure hot water enters liquid suspension by water inlet component simultaneously are once It is spraying in spray head 4b (the secondary injection atomizer 4A used).The reaction force of spray flow in upper spraying type spraying device 13 Itself spray head and fan blade are driven, while rotating machinery wind and injection air keep spray flow cooling, water after cooling drops down onto lower section In water storage tank 2.At the same time, most hot water are last equal through the spraying simultaneously injection cold wind of the oblique upward tower wall of a spray head 4b It falls into return flume 6.Hot water carries out that heat exchange is forced once to be cooled down with air because of atomization and exhausting.Drawn using secondary The excellent low pressure atomizing performance of rotational flow atomized spray injector 4A is penetrated, a warm water in return flume is dropped down onto, recycles height difference through secondary spray Head 4a mist cooling again.Since most flows of cooling hot water are collected by return flume 6, avoiding problems water mist reflux to produce Raw under the wind improves effective gas-water ratio to greatly reduce the ventilation resistance of cooling tower.

Embodiment 2, the combined column that two unit towers (N=2) are constituted are following to constitute.See Fig. 5, Fig. 6.

With existing<gravity water return secondary injection combines cooling tower>the identical structure of combined column:

A) see Fig. 5, there is big tower body 5A, big tower body outer surface is column plate 9, secondary air inlet 10, shutter from top to bottom 11；Big water storage tank 2A, total water outlet 12A are set below shutter.Big tower body lower central has total water inlet group containing water inlet manifold 1 Part includes: a water inlet manifold 1A centre position, and surface sets a large capacity water chamber 15, and is matched with two levels Water pipe 16 is connected to water supply with two reservoir chamber 1.2A below Liang Tai (N=2) spraying device；Every reservoir chamber 1.2A passes through four Oblique sparge pipe 1.3A props up a spray head 4b with annular conduit 1a and N1 above and is connected to water supply；Large capacity water chamber 15 passes through every Platform water inlet vertical tube 1.1A supplies water to every upper spraying type atomising device 13.In being added below every upper spraying type atomising device, reservoir chamber Outer support part 17A, 17B.Large capacity water chamber 15 is fixed on return flume supporting element 18.B) see Fig. 5, Fig. 6, center in big tower body 5A N=2 platform upper spraying type atomising device 13 is set；For height above shutter horizontal plane, every upper spraying type atomising device 13 is equal It is placed in every ventilating duct 14, and is placed on every water inlet vertical tube 1.1A being connected to water inlet manifold 1.On the outside of every ventilating duct A spray head 4b equipped with distribution N1 branch on the annular conduit 1a being connected to water inlet manifold；A sieve is set above every ventilating duct 14 There are inside and outside water collection device 8b, 8a in net air duct 7, sieve air duct upper end.C) every sieve air duct has return flume in tower, gravity returns Water pipe, the secondary spray head 4a of the N2 branch equipped with distribution on lower horizontal return pipe.

It is as follows that 2 combined column of the present embodiment newly designs part:

1) see Fig. 5, Fig. 6, a spray head 4b and a upper spraying type atomising device 13 are propped up to every N1 by total water inlet component The pressure hot water distribution flow-rate ratio of offer is K, and 13 flows of K=N1 branch spray head 4b flow/mono- device=2-3 times are taken in design, Pressure hot water pressure is 0.10-0.20MPa, every spray head 4b total number N1=22 branch.

2) see Fig. 5, a sieve air duct 7 is set above every upper spraying type atomising device 13.See Fig. 6, two neighboring sieve wind 7 lower section of cylinder sets two identical rectangular return flume 6A, opens four discharge orifice 6a, four discharge orifices at each four angles of rectangular return flume Lower section sets four vertical gravity return pipe 3a, and four gravity water return bottom ends pipe 3a are connected to every symmetrically uniformly distributed two groups of horizontal return water It is divided into cloth N2 on two groups of horizontal return pipes of pipe 3b, 3c every and props up secondary spray head 4a；N2=40 branch.

3) see that Fig. 6, two rectangular return flume 6A respectively there are three sides to be attached on big tower body 5A inner wall, used between two rectangular return flume 6A Return flume water-carrying groove 6c connection.See Fig. 5, has sealing 6b between big tower body 5A and rectangular return flume.Every two adjacent prismatics return flume 6A Between lower section set return flume supporting element 18.

4) in every each spray head 4b and secondary spray head 4a installation direction be it is oblique upward, a spray head 4b towards The direction of big tower body 5A inner wall and return flume 6A injection.Secondary spray head generally can be taken as to central-injection it is oblique upwardly-directed.

5) see Fig. 5, height difference h1,1.2 meter < h1 < 1.5 meter of the every spray head 4b away from the rectangular return flume 6 of this are secondary Height difference of the spray head 4a away from the rectangular return flume 6A of this is h2, takes h2 > 3 meter.

Claims (4)

1. gravity water return secondary spray cooling tower, comprising: A) tower body (5), tower body outer surface is column plate (9) from top to bottom, secondary Air inlet (10), shutter (11)；Water storage tank (2), water outlet (12) are set below shutter；Tower body lower central has containing water inlet pipe (1) water inlet component；B) a upper spraying type atomising device (13) is arranged in center in tower body；Height is on shutter horizontal plane Side in ventilating duct (14), and is placed on the water inlet vertical tube (1.1) being connected to water inlet pipe；Connecting on the outside of ventilating duct with water inlet pipe A spray head (4b) equipped with distribution N1 branch on logical annular conduit (1a)；A sieve air duct (7), sieve are set above ventilating duct There is water collection device in air duct upper end；C) sieve air duct has return flume, gravity water return pipe in tower, is equipped with and divides on lower horizontal return pipe The secondary spray head (4a) of the N2 branch of cloth；It is characterized in that

1) pressure hot water that a spray head and a upper spraying type atomising device provide is propped up to N1 by water inlet component and distributes flow-rate ratio For K, K=N1 branch capacity of sprinkler/mono- device flow=2-3 times is taken in design, pressure hot water pressure is 0.10-0.20MPa, one Secondary spray head total number N1≤16；

2) return flume is a rectangular return flume of ring-type (6) along tower body inner wall surrounding, is sealed between rectangular return flume and tower body wall； Four discharge orifices (6a) are opened at four angles of rectangular return flume, lower section sets four vertical gravity return pipes (3a), four gravity at this Return pipe bottom end is connected to two groups of symmetrically uniformly distributed annular horizontal return pipes (3b, 3c)；The secondary spray head total quantity N2 being distributed thereon ≤ 24；

3) spray head and secondary spray head installation direction be it is oblique upward, a spray head is oriented the tower wall surrounding along return flume The direction of injection；

4) h1=1.0-1.5 meters of height difference away from rectangular return flume of a spray head, height difference h2 of the secondary spray head away from rectangular return flume≤ 2.5 rice.

2. by gravity water return secondary spray cooling tower described in claim 1, it is characterized in that: the upper spraying type atomising device uses liquid The upper spraying type atomising device (13) of suspension submerged bearing；Spray head and secondary spray head use secondary injection swirling flow atomizing simultaneously Spray head (4A) uses multiple induced jet type swirling-flow atomizing nozzle simultaneously.

3. by gravity water return secondary spray cooling tower described in claim 2, it is characterized in that the secondary injection rotational flow atomized spray injector It include: that receipts-expansion type (operating) water nozzle (4.2) places cylindrical primary, the secondary injection set for having air inlet (4.7,4.6) outside (4.3,4.5)；In the outer air inlet rectification set (4.4) equipped with cone-shaped inner hole of an injection set, the component sealing being consequently formed is fixed Above the hollow ball shape spin chamber (4.1) of aperture；Spin chamber is connected by tangential water pipe (4.9), flange (4.8) and water inlet component It is logical to supply water.

4. gravity water return secondary spray cooling tower, comprising: A) big tower body (5A), big tower body outer surface is column plate from top to bottom, two Secondary air inlet, shutter；Big water storage tank (2A), total water outlet (12A) are set below shutter；Big tower body lower central have containing always into Total water inlet component of water pipe (1A)；B) center setting N platform upper spraying type atomising device (13) in big tower body；Height is mounted in shutter Above horizontal plane, every is placed in every ventilating duct (14), and is placed on every water inlet vertical tube being connected to water inlet manifold On (1.1A)；A spray head equipped with distribution N1 branch on the annular conduit (1a) being connected to water inlet manifold on the outside of every ventilating duct (4b)；A sieve air duct is set above every upper spraying type atomising device, there is water collection device in sieve air duct upper end；C) every sieve in tower Air duct has return flume, gravity water return pipe, the secondary spray head (4a) of the N2 branch equipped with distribution on lower horizontal return pipe；It is special Sign is

1) the pressure hot water distribution that a spray head and a upper spraying type atomising device provide is propped up to every N1 by total water inlet component Flow-rate ratio is K, and K=N1 branch capacity of sprinkler/mono- device flow=2-3 times is taken in design, and pressure hot water pressure is 0.10- 0.20MPa, every spray head total number N1≤16；

2) a sieve air duct is set above every upper spraying type atomising device, N number of sieve air inlet channel below air duct sets N number of rectangular return flume (6A) opens four discharge orifices at each four angles of rectangular return flume, sets four vertical gravity return pipes, four weights below discharge orifice Power return pipe bottom end is connected to two groups of symmetrically uniformly distributed annular horizontal return pipes, secondary spray head total quantity N2≤24 being distributed thereon Branch；

3) each rectangular return flume (6A) is at least attached in big tower body inner wall on one side, close between rectangular return flume and big tower body wall Envelope is all connected to return flume water-carrying groove (6c) between rectangular return flume between adjacent two unit towers；And every two adjacent prismatic returns Lower section sets return flume supporting element (18) between sink；

4) in every each spray head and secondary spray head installation direction be it is oblique upward, and a spray head is towards big tower body inner wall With the direction of rectangular return flume injection；

5) h1=1.0-1.5 meters of height difference away from the rectangular return flume of this of every spray head, every secondary spray head is rectangular away from this Height difference h2≤2.5 meter of return flume.