US3850595A

US3850595A - Drift eliminator assembly

Info

Publication number: US3850595A
Application number: US00295320A
Authority: US
Inventors: J Forchini; R Garcia
Original assignee: Ecodyne Corp
Current assignee: CUSTODIS-ECODYNE Inc; Ecodyne Corp
Priority date: 1972-10-05
Filing date: 1972-10-05
Publication date: 1974-11-26
Anticipated expiration: 1991-11-26
Also published as: DE2342025A1; GB1414068A; JPS4972756A; IT996252B; CA1012455A; ES418940A1; ZA734641B

Abstract

A drift eliminator assembly for use in combination with a cooling tower including a plurality of drift eliminator panels secured together in an end to end relationship. Each panel includes a plurality of longitudinally extending drift eliminator blades supported at their respective ends by a pair of side plates. The side plates of longitudinally adjacent panels are secured together defining an integral drain channel therebetween. The side plates have openings integral therewith to permit liquid collected on the blades to pass therethrough into the drain channel for discharge to a cold water basin.

Description

bite

Forchini et all.

1 5] Nov; 26,1974

1 1 DRHFT ELIMINATOR ASSEMBLY [75] Inventors: James F. ForchinLl-lealdsburg;

' Ronald M. Garcia, Santa Rosa, both of Calif.

[73] Assignee: Ecodyne Corporation, Chicago, 111. [22] Filed: Oct. 5, 1972 [21] Appl. No: 295,320

[52] 11.8. C1 55/257, 55/443, 55/462, 261/111, 26l/DIG; ll [51] Int. Cl B01d 47/00 [58] Field of Search 261/D1G. 11,111;55/183, 55/221;138/155,163,165,156,157,160,159

[56] References Cited UNITED STATES PATENTS 304.787 9/1884 Butz 138/160 X 433,882 8/1890 Belding 138/165 X 1,047,765 12/1912 Derby 55/257 1,134,976 4/1915 Braemer et a1 55/257 X 1,329,522 2/1920 Griffin 138/157 X 1,855,962 4/1932 Harry 26l/D1G. 11 2,356,192 8/1944 Yingling 55/257 X 2,658,583 11/1953 Fitzgeraldnw 55/445 X 2,752,129 6/1956 Modine 138/157 X 2,808,243 10/1957 Slough et a1. 261/D1G. 11

2,854,090 9/1958 2,911,011 11/1959 2,975,874 3/1961 3,063,471 ll/1962 3,116,989 l/1964 3,465,654 9/1969 3,517,486 6/1970 3,748,832 7/1973 Slough 55/257 Niehart Pagan Murray Warren Fox Golden Furlong et a1. 55/257 Primary Examiner-Frank W. Lutter Assistant ExaminerNeil F. Greenblum Attorney, Agent, or FirmJoe1 E. Siegel; Charles M.

Kaplan ABSTRACT cold water basin.

5 Claims, 5 Drawing Figures in j M 51 1 M 4/ 7a a 6 f2 m1 PATENTEL rmv 2 s 1974 saw 2 BF 2 BACKGROUND AND SUMMARY OF THE INVENTION This invention relates to drift eliminators for eliminating entrained droplets of liquid from a generally upward flow of gas and more particularly to a novel drift eliminator assembly for use in a mechanical draft water cooling tower for removing water entrained in the air as it flows upward through the tower.

In cooling towers wherein liquid is cooled as a consequence of the movement of air therethrough, a substantial amount of the liquid is carried from the'tower by the air unless means is provided within the path of travel of the air to eliminate the liquid and redirect the same downwardly to the intended point of collection within a sump underlying the fill assembly. In some installations the actual loss of liquid in this manner represents a serious difficulty due to the scarcity of the liquid and the difficulty of obtaining the same, and in other installations the presence of the excessive moisture carried out by the stream of air may cause considerable inconvenience and damage to property in the immediate vicinity and in the path of the stream of air.

The drift eliminator assembly disclosed in copending US. Pat. application Ser. No. 161,029, assigned to the same assignee as the present invention, provides an improved drift eliminator assembly including unique drift eliminator blades which efficiently preclude the loss of liquid through the cooling tower air discharge outlet with a minimum of pressure drop in the air stream without substantially interferring with the flow of air through the fill area. The present invention provides a novel support assembly to support the drift eliminator blades, particularly of the type disclosed in theaboveidentified patent application, which permits the efficient removal of the trapped liquid droplets from the blades and directs them into the cold water distribution basin through a series of integral parallel anad inclined drain channels.

It is a primary object of the present invention to provide a drift eliminator assembly which removes entrained liquid droplets from the outlet air and efficiently directs the removed liquid into the cold liquid basin through integral parallel and drain channels. and inclined Another object is to provide a support assembly for securing together a plurality of drift eliminator blades into drift eliminator panels.

A further object of the present invention is to provide a drift eliminator panel which when connected to an adjacent drift eliminator panel forms an integral drain channel therebetween.

A still further object is to provide a side plate for securing a plurality of drift eliminator blades into a structural panel which when connected to the side plate of an adjacent panel forms an integral drain channel therebetween.

Another object of the present invention is to provide a drift eliminator assembly for use in a cooling tower which is compact and may be constructed in factory assembled panels to reduce the field erection time, and which may be readily placed in or removed from its operative position for repair or replacement.

The present invention provides a drift eliminator as sembly for use in combination with a cooling tower including a plurality of drift eliminator panels secured together in an end to end relationship. Each panel includes a plurality of longitudinally extending drift eliminator blades supported at their respective ends by a pair of side plates. The side plates of longitudinally adjacent panels are secured together defining an integral drain channel therebetween. The side plates have openings integral therewith to permit liquid collected on the blades to pass therethrough into the drain channel for discharge to a cold water basin.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which like reference numerals designate like parts throughout the figures thereof and wherein:

FIG. 1 is a side elevational view of a portion of the cooling tower, parts being broken away to show the positioning of the drift eliminator assembly constructed in accordance with the present invention;

FIG. 2 is a side view taken along line 22 in FIG. 1 showing the drift eliminator panels of the present invention;

FIG. 3 is a fragmentary elevational view of the upper portion of the drift eliminator assembly shown in FIG.

FIG. 4 is an enlarged elevational view of a portion of the drift eliminator assembly shown in FIG. 3 showing the connection of the eliminator blades to the side plates; and

FIG. 5 is a sectional view taken along line 55 in FIG. 3 showing the formation of drain channels between adjacent drift eliminator panels.

DESCRIPTION OF A PREFERRED EMBODIMENT for a complete disclosure of a cooling tower of a type contemplated for use of the present invention. Housing 11 includes a top deck structure 12 which defines a water distribution basin 13 thereabove. Liquid, such as water, to be cooled is pumped into the basin 13 from which the liquid drains via suitable metering orifices (not shown) into a fill or packing section 16 positioned immediately below basin 13. After descending through the fill or packing section 16, the liquid is collected in a cold water collecting basin 17 for removal therefrom. Reference is made to US. Pat. No. 3,468,521, assigned to the same assignee as the present invention, for a complete disclosure of preferred type of splash directing fill utilized in cooling tower fill sections.

An air stream is drawn laterally through the tower successively from inlet louver openings 18' through the fill section 16 and drift eliminator assembly 20 and out the fan stack (not shown). As the liquid falls by gravity through fill section 16 it is broken up into droplets by splashing on the. fill. Cooling is accomplished essentially by evaporation from the surface of the liquid droplets and by sensible heat transfer from the liquid surfaces to the circulatingair. During this process, a

certain number of liquid droplets will become entrained in the air stream. These entrained liquid droplets create a nuisance and potential hazard if they are allowed to escape through the fan stack to the outside air. Drift eliminator assembly 20, in accordance with the present invention, prevents these airborne liquid particles from escaping through the fan stack.

Drift eliminator assembly traps the liquid particles in the high velocity exhaust air by redirecting the air flow as it passes therethrough. Entrained liquid droplets impinge and collect on the drift eliminator blades 22 from which the collected water drains down through the tower to basin 17. The construction of the drift eliminator blades 22 as shown in FIGS. 3-5 is fully disclosed in copending U.S. Pat. application Ser. No. 161,029, assigned to the same assignee as the present invention. Blades 22 effectively and efficiently remove the liquid droplets entrained in the air stream and control the direction of air flow in'a manner which minimizes the pressure drop in the air stream. The present invention specifically concerns itself with a unique support structure for directing the collected droplets from the blades 22 back through the tower to basin 17.

Referring to FIG. 2, drift eliminator assembly 20 includes a plurality of eliminator panels 25 secured together in an end to end relationship; each panel 25 includes a plurality of inclined eliminator blades 22 supported by a side plate at their respective ends. Side plates 30 extend vertically substantially the entire height of the panel 25 and include central portions 31, inner flanges 32 and outer flanges 34, as best seen in FIG. 5. Flanges 32 extend outward from the central portions 31 at substantially right angles thereto. Flanges 34 similarly extend outward from the central portions 31 and are formed to include inwardly extending tab portions 36 and outwardly extending connecting ears 38, both extending substantially parallel to central portions 31.

As fully disclosed in copending U.S. Patent application Ser. No. 161,029, as seen in FIG. 4, eliminator blades 22 are constructued as elongated cellular members of substantially V-shape hollow cross-section including a pair of

inclined sections

40 and 42 having equal but opposite slopes.

Sections

40 and 42 are connected together at their converging ends by sections 44. The diverging ends of

sections

40 and 42 have nose sections 46 and 48 integral therewith, which are substantially parallel to sections 44. Stiffener members 45 define the ends of

sections

40, 42, 44, 46 and 48 and serve to increase the rigidity of blades 22. Blades 22 are preferably extruded of a plastic material such as polypropylene or polyvinyl chloride.

Securing blades 22 to side plates 30 in a facing relationship defining passageways 50 between adjacent blades so as to permit the passage of air therethrough are a pair of connecting pins 60 which extend through

openings

62 and 64 formed in side plates 30. Pins 60 include a head portion and a stem portion. The stem portion passes through the

opening

62 and 64 and securely grasps one of the stiffener members 45.

Openings

62 and 64 are dimensioned and shaped to prevent the head portion from passing therethrough. As seen in FIG. 4, openings 64 are L-shaped and therefore leave open areas not closed off by pins 60 to permit water collected on blades 22 to pass therethrough. Pins 60 may be of various designs known in the art. An example of a presently preferred design is disclosed in the above mentioned U.S. Patent application Ser. No. 161,029.

Referring to FIG. 5, longitudinally adjacent panels 25 are secured together by securing together the adjacent side plates 30. The inner flanges 32 overlap one another at their outer edges and the tab portions 36 contact one another so as to space the plates 30 by a predetermined distance and thereby form a drain channel therebetween. A vertically extending support member 72 is sandwiched between the adjacent connecting ears 38 and secured thereto by a connecting pin 75. As seen in FIG. 4, member 72 includes a dogleg type slot 74 to receive pin 75. Support member 72 extends the entire height of assembly 20 and serves to secure vertically adjacent panels 25 together to form a drift eliminator assembly 20 that is rigid and able to withstand the forces applied thereto by the air stream contacting the blades 22.

Drift eliminator assembly 20 is supported from the top deck 12 at its upper end and secured to the foundation defining basin 17 at its lower end. Referring to FIGS. 1 and 3, assembly 20 is suspended from the fill hanger tubings 78 by a support assembly 80. Support assembly 80 includes support members 72 which are secured to side plates 30, support members 82 which are spaced from and parallel to a corresponding member 72, and a plurality of substantially vertically spaced tie members 84 which connect members 72 to members 82. The upper ends of

members

72 and 82 are respectively secured to a corresponding tube 78 by clamps 85 so as to suspend assembly 80 therefrom. The lower ends of members 72 include a support member 86 extending inwardly beyond the inner edges of blades 22 to receive the outer end of a tie rod 87. The inner end of tie rod 87 is threadedly received by an anchor member 88 embedded within the foundation. The angle of inclination of assembly 20 to the direction of flow of the air stream may be accurately erected by changing the effective length of tie rod 87.

In the operation of tower 10, liquid to be cooled is pumped into basin 13 from which the liquid drains into fill area 16 via suitable metering orifices. The liquid then falls by gravity through fill area 16 where it is broken up into droplets by splashing on the fill, and also forms a liquid film on the fill and structural parts. An air stream is drawn into the tower through inlet louvers l8 and then through fill area 16 by suitable fan means. The gravitating liquid is effectively cooled by the stream of air passing through fill area 16 and is collected in cold water basin 17. During the process, a certain number of liquid droplets become entrained in the air stream and create a nuisance and potential hazard if they are allowed to escape to the outside air.

The air stream with the liquid droplets entrained therein flows from fill area 16 through drift eliminator assembly 20, as indicated by arrows in FIG. 1. The liquid entrained air passes through passages 50 between adjacent blades 22 contacting the surfaces thereof causing the entrained liquid to collect on the lower surfaces of passages 50. Since as heretofore mentnioned, blades 22 and consequently passages 50 are longitudinally inclined the liquid collected on the surfaces of passages 50 flows downward toward side plate 30. The liquid then passes through openings 64 in side plates 30 and enters drain channels 70 where it is free to gravitate unobstructed downward into basin 17.

Drift eliminator assembly of the present invention provides more complete deposition of the liquid droplets entrained in the air by efficiently removing the liquid collected on eliminator blades 22 and directing it into basin 17. The unique construction of eliminator panels 25 permits them to be factory assembled to reduce on-site construction costs.

While the embodiment described herein is at present considered to be preferred, it will be understood that various modifications and improvements may be made therein, and it is intended to cover in the appended claims all'such modifications and improvements as fall within the true spirit and scope of the invention.

What is claimed is:

1. In combination with a liquid cooling tower having an air inlet, an air outlet, and means for directing currents of air along a path of travel from said inlet to said outlet in substantially horizontal, intersecting relationship to liquid gravitating within the tower, a drift eliminator assembly within the tower, disposed to remove droplets of liquid entrained in said air immediately prior to discharge of said air through said outlet;.said drift eliminator assembly comprising:

a. a plurality of drift eliminator panels secured together in an end to end relationship;

b. each of said panels including a plurality of longitudinally extending drift eliminator blades positioned one above the other and supported at their respective ends by a pair of side plates;

c. said side plates of longitudinally adjacent panels being secured together so as to define an integral drain channel therebetween;

d. said side plates having openings integral therewith and said eliminator blades being inclined so as to permit liquid collected on said blades to flow through said openings into said drain channel;

e. each of said side plates includes first and second flanges extending longitudinally outward therefrom towards the adjacent side plate such that corresponding first flanges and corresponding second flanges of adjacent side plates are in contact with one another so as to form said integral drain channel therebetween;

f. said first flanges include connecting ears integral therewith for receipt of fastening means therethrough so as to secure together longitudinally adjacent side plates; and

g. vertically extending support members secured between adjacent pairs of said connecting ears for suspending said drift eliminator assembly within said tower.

2. The invention as defined in claim 1 wherein each of said eliminator blades is secured to said side plates by pin means having a shank portion which extends through said side plate openings to grasp said eliminator blade and a head portion dimensioned to prevent passage of it through said side plate opening.

3. The invention as defined in claim 2 wherein said side plate opening is shaped so as to prevent said head portion from passing therethrough while permitting liquid from said eliminator blades to flow therethrough into said drain channel.

4. The invention as defined in claim 1 wherein the outer ends of said first flanges are curled inward in abutting relationship with the corresponding curled outer end of the longitudinally adjacent side plate.

5. The invention as defined in claim 4 wherein the outer ends of said second flanges abut one another in an overlapping relationship.

Claims

1. In combination with a liquid cooling tower having an air inlet, an air outlet, and means for directing currents of air along a path of travel from said inlet to said outlet in substantially horizontal, intersecting relationship to liquid gravitating within the tower, a drift eliminator assembly within the tower, disposed to remove droplets of liquid entrained in said air immediately prior to discharge of said air through said outlet; said drift eliminator assembly comprising: a. a plurality of drift eliminator panels secured together in an end to end relationship; b. each of said panels including a plurality of longitudinally extending drift eliminator blades positioned one above the other and supported at their respective ends by a pair of side plates; c. said side plates of longitudinally adjacent panels being secured together so as to define an integral drain channel therebetween; d. said side plates having openings integral therewith and said eliminator blades being inclined so as to permit liquid collected on said blades to flow through said openings into said drain channel; e. each of said side plates includes first and second flanges extending longitudinally outward therefrom towards the adjacent side plate such that corresponding first flanges and corresponding second flanges of adjacent side plates are in contact with one another so as to form said integral drain channel therebetween; f. said first flanges include connecting ears integral therewith for receipt of fastening means therethrough so as to secure together longitudinally adjacent side plates; and g. vertically extending support members secured between adjacent pairs of said connecting ears for suspending said drift eliminator assembly within said tower.