US3498590A - Spiral draft water cooling tower - Google Patents

Description

March 3, 1970 D. B. FURLONG 3,498,590

SPIRAL DRAFT WATER COOLING TOWER Filed June 15, 1968 3 Sheets-Sheet 1 I/v VEN roe Do/v/v B F021. o/vs firroeusvs.

March 3, 1970 D. B. FURLONG 3,498,590

SPIRAL DRAFT WATER COOLING TOWER Filed June 13, 1968 3 Sheets-Sheet 2 FIG 3.

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March 3,1970 D, B, FURLONG 3,498,590

SPIRAL DRAFT WATER COOLING TOWER Filed June 15, 1968 5 Sheets-Sheet :5

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INVENTOE. DON/VB. FUeLa/VG United States Patent O 3,498,590 SPIRAL DRAFTWATER COOLING TOWER Donn B. Furlong, Santa Rosa, Calif assignor to Fluor Products Company, Inc., Santa Rosa, Califl, a corporation of California Filed June 13, 1968, Ser. No. 736,833 Int. Cl. F28c 1/00 US. Cl. 261-411 7 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION This invention relates generally to water cooling towers, and more specifically concerns an unusually advantageous and economical tower construction with substantially increased water cooling capacity.

Conventional mechanical draft and natural draft towers typically employ grid decking or packing for draining and splashing water in such dispersed condition as to be cooled by air streams passing generally horizontally through the packing. The packing decks normally extend continuously along the side or sides of such a tower in order to achieve direct inward flow through the pack ing of all air passing between the exterior and interior of the tower, this having been thought to be consistaut with most economical tower construction and mode of operation. For example, it was thought that continuity of packing extent along the tower sides achieves maximum surface to area ratio, the surface referring to available wetted packing area presented to the entering air, and area referring to the ground area covered by the tower.

It has been found, however, that the construction and operation of conventional towers present certain problems and lack of desired economies. For example, louvers are required to guide air flow into the packing and to intercept water splashing outwardly from the grid decking. In cold weather, the water splashing in this manner tends to freeze on the louvers with resultant build-up of ice that can reduce air flow into the tower and damage the tower structure. Added equipment to overcome such icing may include extra conduit and-valving to drain warm water onto the louvers, all of which adds to the expense of tower construction and operation.

BRIEF SUMMARY OF THE INVENTION It is a major object to provide a tower construction such as will overcome the above referred to problems, as well as others, while at the same time providing unusual advantages contributing to reduction in space occupied by a tower of given capacity, elimination of need for louvers, and a gain in tower operating economy. Basically, the invention is embodied in a tower construction that includes multiple packing sections having inlet and outlet sides laterally separated in a direction generally lengthwise of the tower horizontal periphery; the sections being spaced in that direction for reception of air (or other gas) therebetween prior and subsequent to air flow through the sections between said sides so that "ice the flow through the sections has substantial components parallel to said direction; and means to supply water (or other liquid) for drainage within the sections to be cooled by the air flow therethrough. As will appear, the-invention may be incorporated in either natural draft or mechanical draft towers.

Typically, the tower construction may include certain partitions extending within the spaces between the packing sections to confine the air to enter the sections at the inlet sides and to flow laterally within the sections, such partitions for example extending diagonally between the outer extents of the outlet sides of the sections and the inner extents of the inlet sides of the sections. Further, the tower construction may include other partitions covering the outermost and innermost extents of the sections.

Additional objects and advantages of the invention include the provision of such decking sections circularly arranged about a vertical central axis with section elongation generally radially; the provision of decking sections in a row with parallel elongation normal to the straight direction of tower side extent; the provision of decking sections arranged in a row with dimensional elongation in staggered relation; the provision of water supply means including a water basin overlying the sections and spaces there between, the basin having drainage openings located only over the sections; the provision of means including piping having water outlets directed to discharge water into the basin to flow there along and over the sections and spaces there between; the provision of means to supply warm water to fall in curtains at the entrances to those spaces which receive air between the sections, for flow through the sections, in order to warm that air in cold weather to prevent icing, no louvers being required; and the provision of a basin underlying such spaces to receive water splashing into the spaces from the decking sections.

These and other objects and advantages of the invention, as well as the details of illustrative embodiments, will be more fully understood from the following specification and drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective elevational showing of one form of natural draft tower incorporating the invention;

FIG. 2 is a fragmentary plan view of a portion of the FIG. 1 tower, and partly broken away to show interior construction;

FIG. 3 is an enlarged elevation taken in section on lines 3-3 of FIG. 2;

FIG. 4 is an enlarged elevation taken in section on lines 44 of FIG. 2;

FIG. 5 is schematic plan view of another arrangement of decking sections and partitions;

FIG. 6 is a schematic plan view of a further arrangement of decking sections and partitions;

FIG. 7 is a schematic plan view of yet another arrangement of decking sections; and

FIG. 8 is a section showing a modified tower construction having louvers at the inlet ends of the spaces between the packing sections.

DETAILED DESCRIPTION OF THE INVENTION Referring first to FIGS. 1-4, the illustrated water cooling tower 10 is of natural draft type, wherein air is drawn horizontally into the lower interior of the tower and rises in the stack 11 of hyperbolic outline in vertical axial planes. The stack is circular in horizontal planes as is the lower portion 12 of the tower. While the invention is not limited to such natural draft towers, it has unusual advantage when incorporated therein.

Included in the tower is a plurality of Water receiving packing sections having inlet and outlet sides laterally separated in a direction generally lengthwise of the tower horizontal periphery. As seen in FIG. 2, the sections 13 are rectangular in plan view with inlet and outlet sides 13a and 13b separated in the circumferential direction. Further, the sections 13 are circularly arranged about the vertical central axis of the tower with spacing there between indicated at 14 for reception of air between the sections. Air entering the tower spaces 14a then turns to flow through the sections 13 between sides 13a and 13b, and is then received in spaces 14b for subsequent passage to the tower interior. Arrow 15 designates the general flow path. As is clear from FIG. 2, the fiow through the sections 13 has a substantial component 15:: parallel to the (circumferential) direction of the lower horizontal periphery.

Another aspect of the invention has to do with the I provision of certain partitions extending within the spaces 14 to confine the air to enter the sections 13 at their inlet sides to flow laterally therein as described. For example, vertical partitions 16 may be provided to extend diagonally between the outer extents 17 of the outlet sides 13b of the sections 13 and the inner extents 18 of the inlet sides 13a of the sections. Further, other vertical partitions 20 and 20 are provided to cover the outermost and innermost extents of the sections 13, whereby the tower appears in FIG. 1 as inwardly recessed at 14a.

Typically, the like sections 13 are radially horizontally elongated and the overall radial dimension of the section multipliedby the number of such sections substantially exceeds the boundary dimension (as for example circumference) defined by the outer extents of the sections. Accordingly, a substantially higher than normal ratio of surface to area is achieved, these terms having been previously defined.

Referring now to FIG. 5, packing sections are shown spaced apart linearly at 31, as in the case of a rectangular tower construction. Air enters the Spaces 31a, flows through the sections via their inlet and outlet sides 30a and 30b, and enters the tower interior via the spaces 31b, arrow 32 indicating such flow. Diagonal partitions 33, and partitions 34 and 34a at the inner and outer ends of thesections, serve the same functions as the previously described partitions.

FIG. 6 illustrates an arrangement of inwardly elongated packing sections 35 similar to that of FIG. 5; how ever, the air flow is caused to follow the paths indicated by arrows 36 and 37. This divided flow pattern is effected by provision of partitions 38 and 39 extending between pairs of the sections 35 at their inner and outer sides respectively, in such manner that certain alternate spaces 40 between the sections 35 are outwardly covered and inwardly exposed to the tower interior, and other alternate spaces 41 between the sections are inwardly covered and outwardly exposed to the tower exterior. In both FIGS. 5 and 6, the long dimensions 1 of the sections are greater than the dimension d of the spaces between the sections, whereby the surface to area ratio referred to above is substantially enhanced.

In FIG. 7, the decking sections 44 and 45 are arranged in a row and are dimensionally elongated in staggered relation, i.e. the sections extend lengthwise in zig-zag fashion. This arrangement results in the creation of certain alternate spaces 46 which are outwardly exposed and inwardly closed and other alternate spaces 47 between the sections which are exposed toward the interior of the tower, but outwardly closed. Partitions 48 and 49 at the ends of the sections prevents air flow through those ends, and aid divided air flow in the directions as indicated by arrows 50 and 51. Here again the total length of the sections through which the air flows is much greater than the peripheral length of the tower along its outer side or sides.

Referring back to FIGS. 1-4, means is provided to supply liquid, as for example water, for drainage within the sections in order to be cooled by air flow through the latter, the water typically falling in dispersed drops which splash and film on the decking surfaces or slats. Many different types of decking or fill may be used, FIG, 4 indicating a closely packed section 13 of such fill as inclined downwardly and in the direction 15 of air flow through the fill, water particles tending to fall in the packing with corresponding angularity from vertical. Tower structure supporting the fill includes uprights 55, cross pieces 56 and bracing 57. An upright drift eliminator 58 is spaced close to the outlet side 13b of the packing for eliminating drift particles from the air stream.

The water supply means illustrated in the drawings includes a water basin 60 overlying the packing sections 13 and the spaces 14a and 14b there between. As seen in FIG. 3, hot water may be pumped from a concrete supply conduit 61 upwardly within a riser 62 to a flume or piping 63 extending transversely and inwardly across the basin 60. The latter has multiple outlets 64, individually valve controlled at 65, directed to discharge water into the basin for open channel flow there along in the length direction of the basin. The basin has intermittent groups 66 of drainage openings 67 located lengthwise thereof, for draining water into and onto the decking or packing sections 13; also the basin over the spaces 14 between sections 13 is free of such holes so that water does not drain from the basin into the interiors of those air spaces. On the other hand, any water splashing from the packing into the spaces 14 falls into the collection basin 69 at the bottom of the tower, and no louvers are needed to intercept such splash since spaces 14 are within the tower.

Further, means is provided to supply warm water to fall in curtains at the entrances to spaces 14a, in heat transfer relation with air received into the spaces 14a, whereby in cold Weather the air is pre-heated before it reaches the packing sections to prevent icing. In the illustrated embodiment of FIGS. 1-4, the basin 60 extends outwardly over the air entrances to spaces 14a, and localized groups 70 of drainage outlets are provided in the basin to drain water in curtains at those entrances.

To complete the description, access walkways are shown at 71 over the piping 63; walkway 72 extends along and at the inner side of the basin 60; and openable and closable auxiliary air inlet structure 73 extends between the basin and the stack 11 for allowing auxiliary cool air to enter the tower and thereby reduce the natural draft induced flow of air through the packing sections 13 in extremely cold weather, helping to prevent icing of those sections.

Finally, FIG. 8 illustrates an alternate arrangement wherein the packing sections and partitions are the same as in FIG. 2, excepting that outermost partition 20 is not used. Instead, a series of vertically spaced, downwardly and inwardly inclined louvers is substituted to provide more flexible air flow with less pressure drop under certain conditions. Louvers 80 extend near the outer extremities '81 of the sections 13, to direct air to flow into the sections, while intercepting any outward splash. A curtain 82 of warm water falls from the basin 83 and between the louvers and the section 13, suitable water pass ing openings being provided in the basin. Curtain 82 warms the entering air and the louvers to prevent icing in winter.

I claim:

1. In a cooling tower having a generally circular horizontal cross section and a vertical axis, the combination comprising a plurality of upright generally annularly spaced packing sections having open inlet and outlet sides laterally separated in a direction generally lengthwise of the tower horizontal periphery,

the sections being spaced in said direction and about said axis for reception of gas therebetween prior and subsequent to gas flow through the sections between said sides so that the flow through the sections has substantial components parallel to said direction, said sections also being radially outwardly spaced from said axis,

certain upright partitions located in said spaces between the sections and extending generally diagonally between the outer extents of said outlet sides of the sections and the inner extents of said inlet sides of the sections, thereby to direct the gas to flow in a spiral course about said vertical axis as the gas passes through said sections and into the tower interior inwardly of said sections, said certain partitions extending vertically throughout approximately the heights of said sections, there being other partitions located at the radially inner and outer ends of the sections to block air flow through the outermost and innermost extents of said sections, said sections being radially inwardly elongated,

and means to supply liquid for drainage within said sections to be cooled by the gas fiow therethrough, said gas flow in a spiral course inducing enhanced mixing of the moisture laden gas so as to decrease the density thereof thereby to increase the tendency of the gas to rise in the tower.

2. The combination of claim 1 in which said supply means includes a water basin overlying said sections and spaces and having intermittent groups of drainage openings located there along.

3. The combination of claim 2 wherein said supply means includes piping having water outlets directed to discharge water into the basin to flow there along in said direction.

4. The combination of claim 1 including means to supply warm water to fall in curtains at the entrances to said spaces which receive air for flow laterally through the sections.

5. The combination of claim 1 including a water receiving basin underlying said spaces to receive water splashing into said spaces from said packing sections.

6. The combination of claim 1 including air inlet louvers at the outer extremities of said spaces, the louvers inclined downwardly and toward said outer extremities.

7. The combination of claim 6 wherein said liquid supply means includes basin openings to pass water to drain in curtains between said outer extremities and said louvers.

References Cited UNITED STATES PATENTS 1,577,703 3/1926 Fedeler 484 X 1,865,245 6/1932 Goodloe 55-484 X 2,044,221 6/1936 Myers et al 55484 X 2,055,774 9/1936 Ray 55484 X 2,732,190 1/ 1956 Mart.

HARRY B. THORNTON, Primary Examiner STEVEN H. MARKOWITZ, Assistant Examiner US. Cl. X.R.

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