US2892509A - Drift eliminator assembly for cooling towers - Google Patents

Description

June 30, 1959 D. R. BAKER ETAL 2,892,509

' DRIFT ELIMINATOR ASSEMBLY FOR COOLING TOWERS Filed July 16, 1956 4 sheets-sheet 1 INVENTORS. 0040/0 r fid/cer Home/ E. FO/Wj/CZ BY Arman 4 DRIFT ELIMINATOR ASSEMBLY FOR COOLING TOWERS Filed July 16, 1956 4 Shets-Sheet 2 IN V EN TOR5- 00/74/42 3 Baker June 30, .1959 D. R. BAKER ET AL 2,892,509 DRIFT ELIMINATOR ASSEMBLY FOR COOLING TOWERS Filed July 16, 1956 v 4 Sheets-Sheet :5

BY ,0 i

ATrORN K June 30, 1959 D. R. BAKER ET Al. 2,892,509

DRIFT FLIMIIUXTOR ASSEMBLY FOR COOLING TOWERS Filed July 16, 1956 4 Sheets-sheaf 4 WZMM I mm; 70

INVENTOR5. 00/74/4 Baker I Homer Ford ca I Z f DRIFT ELIMINATOR ASSEMBLY FOR-'- COOLING TOWERS Donald.-R...Baker,.Blue Springs, and. Homer E. Fordyce,. GaShland;.,Mo., assignors. to. The, Marley Company,

Kansas City, M00, a corporation of Delaware Application Iul3e16; 19.56;- Serial No..59.8,17.4} 9; 01 or; res-ea 'lfhis inventiorn relates:to.-.-v improvements in water cool-.- towerawhereinheatremoved from. the water by. stnface. evaporation, and; particularly to; improvements.

in-drift eliminatorssfor towers, of suchEnature,theIpri-.- mary object, being to} provide} enecnv. elimination of watenfr omrthe. outgoing .air withtrnin imum pressureloss.

In,cooling-:towers whereinwateu is cooledasa conses qnenceof the movementioflaiu therethrough, asubstanaL amount: of. the water carried. from. the, tower. by. the. air unless'means is. providedv within the.path of travel.

of, the .air' to. eliminate. the water. and redirect the same. downwardlyv to thelfintended pointof collection within.

a surnp nnderlyingthefill. assembly. a

Reference may be had to..U.S. LettersPatent' No. Re. 2.l.,fl9.4,'.iss-ued.in thenameof. Leon I. Mart, n..May 6, 19.41., ,for. k n-understanding. of the type. of. water. cooling tower to. which the instant invention. relates. and the. na: tu'reand dispositionfof. conventional drift. eliminators commonly, employed therein, The same are employed not-.onlypincrossfiow towers, b.ut.in. those operating on.

a;co,u nterfiow principle asevidenced by US, LettersrPat- Chi. 1.3 Q T ZQ 28', ,isisuedf March. 16, 1-954.

While drift eliminators heretofore suggested and7or employed in: thisfield? have effectively and; efficiently served both functions 'ofguiding'or turning the air as itemanates from the. fillassembly in. the direction of toprovide a drift eliminatorthat advantageously utilizes.

the differences in the mass" of water and air to cause separation thereofwithin the eliminator and prior to" ultimate discharge of the airfrom the tower.-

v A furth'e-r object of'the instant invention is to-provide arr improved drift' eliminator that'automatically redirectsth'ewater removed fromthe air into' gravitating streams channeled along thesupportsfor the-vanes, thereby. minimizing; the drift from the. unit;

' Awstill: further: object of. the present. invention. is: to

provide: an eliminatorrthat: gently turns the air in. the

direetiomof: flow thereof: from the tower: as. gravityv tends torincreasethe; angle of impingement of the water on;

the.' vane surfaces, thereby increasing the effectiveness of the vanes as drift eliminatorsa In the drawings:

. Figured, isa sidefilevatiqnahview: of a water cooling towenpartsbeing; bro-ken away to show a drift eliminator} made; pursuant to. one; form of the-instant invention.

-E ig; 2. is; a crossfsectionalview taken on line III.I ofj Fig, 1

.Fig 3t is, a;fragnrentary, cross-sectional view of a drift eliminator embodying another form of; the instant, in-

vention takenon, line llllllofifie certain parts;

2,892,509 B ten d e 0 1959.

2. thereof beiugbroken away to revealvdetails ofconstruction.

Fig. 4' isa. fragmentary, cross-sectional view showing theelirninator of Fig.3 in. elevation taken online IVIV of. Fig, 3, parts being; broken away for clearness.

Fig. 5 is an elevationalview. of another type of'water cooling ytowenparts being broken away tovreveal a drift eliminator made pursuant'to another embodiment of the instant invention.

Fig. 6' is an enlarged," fragmentary, vertical, crosssectional view through a portionof the eliminator shown. in.Fig. and V Fig. 7; is a fragmentary cross-sectional view taken onvrlineVllE-rVlI oflFig. e;

n' al essential i r ec s. co ling we 10 sh wn n. Fig. Lof the drawin'gs; is same that illustrated" iuztlie aforementioned Patent No; Re, 2'1 ;79.4 in that; Water; is cooled through use: offill. assemblies broadly designated by the numeral andjthrough which air is. forced byuse of a; fan unit lfl'. Hot water. iscollected; inanopen top basin 16; fordistributing the same to thefassemblies 12 therebelow. Intermediate basins 18; between the assemblies 12, collect-thecooledwater and transfer the same laterally v 'hereby to. redistribute the; same. to the assembly therebel'ow:. The cooled Water iscollected in asurnpfior passageto a1 pointfof use in the saniemanner as shown ahdfdieseribedinthe last'men tioned patent; V

' It'-'is*seenthat the ainfiowshorizontally'throughthe assemblies 12 incrossflow relationship to the g ravitating water; and'the hot, airisultimatelydischargedf vertically from the tower--10 through outlet- 20' within which the fanassembly 14 is disposed; The force of' air causes the gravitating: water to drift laterally at an; angle: to the vertical substantially a-fthe assemblies 12 are in: clined in'Fig. if, andth'erefore,itbecoines necessary tov provide drift eliminatorbroadly-designated by the nu: moral 22 within the tower 1 0 at.the outlet. endsof-the' assemblies 12 to remove the water entraihed in the air and redirectthe same downwardly tn the. underlying sump. g g t V I Eliminator'22'shownin Figs.- land 2, is-of special construction differing substantially from those heretoforeemployed'in this fieldfor the purpose of" more effectively removing the water-and"controlling the direction of air fl'ow so as: to-r ninimizepressure loss Toaccomplish these-results the eliminator 22 consistsofa plurality of. horizontally aligued supports 24 that are preferably reetangularand disposed with theirlongitudinal axesinclined downwardly and inwardlytoward the underlying sump and such inclination also disposes the transverseaxes of the supports 24 on an incline'opp osite to the" direction of inclination of the longitudinal axes of sup; ports24. It is thus seen that both longitudinal edges of the supports 24 are inclined; but; as seen inFig; 2, it is to be" preferred that theoppo'sitefaces of the sup ports 24 be vertical. i

As'will hereinafter appear; the horizontal spaced supports 24 serve a dual function;- namely, that of supporting elongatedvanes or slats 26; as well as channel'theofathe. vanes 26: are inclined The longitudinal'inclina tion of the vanes 26 is seen in Fig. 2 of the drawings and it is to be noted that the direction of inclination of the vanes 26 of section 28 is opposite to the directlon of inclination of the vanes 26 of section 30.

Where possible, it is to be desired that the vanes all incline downwardly and inwardly toward a center line with respect to the vertical axis of rotation of fan 14. In other words, if, for example, a drift eliminator is provided with four end-to-end sections, the fourth section disposed to the left of section 28, would have its vanes incline in the same direction as the vanes 26 of section 28 and, therefore, oppositely to the direction of inclination of vanes 26 of the two sections 30 and 32.

The inclination of the vanes 26 transversely thereof is seen in Fig. l of the drawings and it is apparent that desirably such angle of inclination be approximately 45 degrees, thereby bisecting the angle between the horizontal path of travel of the air as it emanates from the assemblies 12, and the vertical path of travel thereof as the air moves upwardly through the outlet 20. Consequently, all of the air and water entrained therein, strikes the innermost inclined faces of the vanes 26 and is gently turned or redirected upwardly toward the outlet 20. While the air and water move at substantially the same velocities, the air tends to move upwardly and thereby separate from the water as the latter, being substantially heavier, tends to continue moving horizontally against the vanes 26.

While much of the water thus removed gravitates forthwith from the eliminator 22 to the collecting sump therebelow, a substantial amount of the removed water flows longitudinally of the vanes 26 and water that does not drop from the lowermost edges of the vanes 26 by virtue of the transverse angularity of the latter, moves against the inclined supports 24 by virtue of the intersecting relationship of the vanes 26 and the supports 24.

When the water channeling along the vanes 26 longitudinally thereof strike the upright supports 24, its direction is changed and such water thereupon either gravitates from the vanes 26 adjacent the supports 24, or channels downwardly along the latter in a plurality of streams to the water collection basin. v

It is to be noted further that the vertically spaced vanes 26 are relatively overlapped so that at no point throughout the entire area of the eliminator 22, is it possible for any air and water to flow therethrough without being subjected to the removal action just above described.

Still another advantage of longitudinal inclination of the vanes 26 lies in the fact that the removed water is caused to flow in one direction and thereby separate from the air as the action of fan 14 continues to move the latter and prevents such air from flowing with the water toward the lowermost ends of the vanes 26. Thus the stop is knocked out of the droplets of water which are separated from the air. In other words the tendency of the droplets to stop and remain on the slats 26 is eliminated since due to the double inclination of the upper surfaces of slats 26 the droplets are deflected downwardly in two directions to facilitate gravitation of the same along the slats.

In Figs. 3 and 4 of the drawings there is provided a drift eliminator 34 composed of a pair of banks 36 and 38, the bank 36'being proximal to the fill assembly of' the cooling tower (not shown in Figs. 3 and 4), and the bank 38 being proximal to the air outlet of the tower. In all respects the bank 38 is identical with the drift eliminator 22 and need not be further described. The

bank 36 however, differs in that the transverse angle of inclination of its vanes 40' is less than the angle of transverse inclination of vanes 42 of the bank 38. Furthermore, as seen in Fig. 4, the vanes 40 incline. longitudinally thereof in a direction opposite to the direction of inclination of the longitudinal axes of the vanes 42. In other words, the bank 38 is subdivided into a plurality of end-to-end sections 44 and 46 as in the case of the 4 eliminator 22, and the bank 36 is likewise subdivided into a plurality of corresponding sections 48 and" 50 respectively.

Fig. 4 of the drawings illustrates clearly the way in which the longitudinal axes of the vanes 40 of section 48 incline oppositely to the longitudinal axes of the vanes 42 of section 44. The samearrangement is provided between the vanes 40 and 42 of sections 50 and 46 respectively.

At least two additional advantageous results are made, possible through use of eliminator 34 not included 111" the principles of the eliminator 22. First, as tlie'water entrained air impinges upon the uppermost and innermost faces of the vanes 40 the direction of travel thereof is changed slightly, but the turning action is increased more sharply as the same impinges upon the uppermost and innermost faces of the vanes 42. In this respect therefore, the water and air tend to separate within the bank 36 of the eliminator 34 and more complete separa-,

tion takes place as the direction of travel of the air more closely approaches the vertical within the bank 38 and as the water is deflected from the upper surfaces of the vanes 40 to the upper surfaces of the vanes 42.

Still further, it can be seen by comparing Figs. 3 and 4, that the air and water are forced through a tortuous path of travel within eliminator 34 since the vanes 40 tend to cause movement upwardly in one direction Ion-- gitudinally thereof and as soon as the air and water reaches the bank 38, its course is changed-and the same tends to move upwardly at an angle in the opposite direction along the longitudinal axes of the vanes 42.

In any event however, removed water channeling along the vanes 40 comes into contact with inclined spacers or supports 52 that intersect the vanes 40 and water; channeling in the opposite direction longitudinally of the vanes 42, comes into contact with inclined supports 54 for the vanes 42. Such channeling induces gravita-' tional flow of the removed water in streams following the longitudinal axes of the supports 52 and 54, thereby more effectively eliminating the water from the outwardly moving hot air, all without appreciable pressure loss.

The cooling tower illustrated in Fig. 5 of the drawings ismuch inthe nature of one of the forms disclosed in Patent No. 2,672,328 and illustrates the manner of carrying the principles of the instant invention through use of a generally horizontal drift eliminator 56 in a counterfiow type of arrangement. In this respect, fan

58 directs the air vertically through the fill assembly (not shown) in a direction opposite to the fiow of water emanating from nozzles 60 of manifold 62, the cool air entering below the fill through inlets 64.

Eliminator 56 includes a plurality of sections 66 having adjacent sections inclined oppositelyl'as seen in Fig.

5. Each section includes a plurality of horizontally spaced, longitudinally horizontal and transversely inclined.

supports or spacers 68. Each section 66 is also provided with two banks 70 and 72 of eliminator vanes 74. All

of the vanes 74- are longitudinally inclined as seen in Figs. 5 and 6 and transversely inclined as seen in Fig. 7.

Furthermore, the vanes74 are all .in intersecting relationship to the supports 68 and preferably pass loosely therethrough. While all of the vanes 74 of any given section 66 are inclined longitudinally in the same direction, the vanes 74 of the lower bank 70 of each sectionare inclined transversely in a direction opposite to vanes site to the direction of transverse inclination of the vanes 74d of lower bank 70.

Here again, the air and water are caused to traverse a tortuous path through the eliminator 56, but in a manner differing from the way in which the tortuous travel is accomplished in eliminator 34. The vertically moving water entrained air striking the lowermost inclined faces of the vanes of bank 70 is deflected laterally from the vertical in one direction toward the lowermost faces of the vanes of the bank 72. When the same impinges upon the lower faces of the vanes of bank 72, the direction of travel is again deflected in the opposite direction toward the fan 58. Each time that the direction of travel of the water entrained air is changed, the differences in Weights between the water globules and the air particles causes the water to separate from the air. In other words, as the air impinges upon the vanes, its course of travel is rather easily changed, Whereas the water being heavier tends to continue its normal course and be deflected at a different angle from the angle of deflection of the air.

In virtually all other respects, the eliminator 56 operates the same as the eliminator 34 and for that matter, the eliminator 22, since the removed water channeling downwardly at an angle longitudinally of the vanes 74 either gravitates from the lowermost edges of the vanes 74 or moves to a point where its downwardly inclined travel is intercepted by the spacers 68.

It is now apparent that in all three forms of the invention there has been presented a drift eliminator capable of maximum removal of water from the hot air that tends to drift therewith from the fill assembly to the hot air outlet of the tower. At the same time, each of the eliminators is so constructed as to gradually, progressively and gently change the course of travel of the air, thereby increasing the separating action of the water therefrom and doing so without pressure loss.

It is recognized that any obstacle to the flow of air tends to produce a drop in pressure, but it has been found that through use of the eliminators of the kind above described, such pressure loss is of virtually no consequence and, therefore, a minimum amount of water is carried from the tower by the hot air, all without any deleterious effects whatsoever upon the overall efficiency of the system.

Having thus described the invention what is claimed as new and desired to be secured by Letters Patent is:

1. In combination with a water cooling tower having an air inlet, an air outlet and means for directing currents of air along a path of travel from the inlet to said outlet in substantially horizontal, intersecting relationship to water gravitating within the tower, a drift eliminator within the tower, disposed to remove droplets of water from the air immediately prior to discharge of the air through said outlet, said drift eliminator comprising a plurality of elongated slats, each having a pair of opposed fiat faces, and structure supporting the slats in an inclined stack intersecting said currents of air with the upper slats of said stack disposed in closer proximity to said inlet of the tower than the lower slats of the stack, said slats being parallel, disposed in vertically spaced relationship with the longitudinal axes thereof inclined transversely of said path of travel of the air and the transverse axes of the upper faces thereof transversely inclined whereby to present a double slanted uppermost face on each slat respectively, said double slanted faces being disposed for direct impingement of the moisture laden air thereagainst to deflect the latter upwardly and outwardly toward said air outlet while the droplets of water in said moisture laden air are deflected downwardly with the stop being knocked out of the same and causing the water to gravitate rapidly down respective slats out of the high velocity air currents,

2. The combination as set forth in claim 1 wherein said supports include a number of horizontally spaced, upright, parallel, elongated, longitudinally and transversely inclined members.

3. The combination as set forth in claim 1 wherein is included a pair of said stacks disposed in parallel, horizontally spaced relationship, the longitudinal axes of the slats of one stack being inclined in one direction and the longitudinal axes of the slats of the other stack being inclined in the opposite direction.

4. The combination as set forth in claim 3 wherein said stacks lie in planes intersecting the path of travel of said currents of air.

5. The combination as set forth in claim 4 wherein said stacks are aligned and disposed in horizontally spaced planes whereby the slats of one stack are in crossed relationship to the slats of the other stack.

6. The combination as set forth in claim 5 wherein the pair of stacks are disposed in suflicient proximity that one of the stacks is in overlying, superimposed relationship to the other stack.

7. The combination as set forth in claim 1 wherein said stacks are subdivided into a plurality of end-to-end sections, the direction of longitudinal inclination of the slats of certain sections differing from the direction of longitudinal inclination of the slats of other of the sections.

8. The combination as set forth in claim 3 wherein the angle of transverse inclination of the transverse axis of the slats of one of the stacks is greater than the angle of transverse inclination of the transverse axis of the slats of the other stack.

9. The combination as set forth in claim 8 wherein the stack having slats disposed in greatest transverse angular inclination is located in closest proximity to the air outlet of the tower.

References Cited in the file of this patent UNITED STATES PATENTS 1,156,511 Wood Oct. 12, 1915 2,252,242 Wood Aug. 12, 1941 2,349,944 Dixon May 30, 1944 2,356,192 Yingling Aug. 22, 1944 2,583,171 Green et al. Jan. 22, 1952 2,627,396 Simons Feb. 3, 1953 FOREIGN PATENTS 167,775 Germany Feb. 14, 1906 304,815 Germany Apr. 16, 1918 25,449 Great Britain Nov. 12, 1906

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