US3434529A - Dry cooling towers - Google Patents

Description

March 25, 1969 J. H. DALTRY DRY; COOLING TOWERS ofS Sheet Filed Dec. 12, 1966 APPLICANT u w 1 t g u n m d & 1 m a m g n e h B wmm Attorneys March 25, 1969 Filed Dec. 12, 1966 J. H. DALTRY DRY COOLING TOWERS Sheet 3 o3 III/ March 25, 1969 J. H. DALTRY 3,434,529

DRY COOLING TOWERS Filed Dec. 12, 1966 Sheet 3 U.S. El. 16547 2 Claims ABSTRACT OF THE DISCLOSURE Referring to the drawings, in a dry cooling tower the base of the tower shell is supported clear of the ground to provide a peripheral opening and coolers are disposed around and within said peripheral opening. The coolers 20 are grouped in sectors 19 each comprising a plurality of rows, said rows being at different levels so that, between them, they extend over the height of said peripheral opening. Each row is provided with a pair of water ring mains 37, 38 which extend parallel to and adjacent the lower end of said row and each cooler of said row is connected at its lower end across said ring mains. The arrangement of the present invention provides a dry cooling tower in which the coolers have good thermal and hydraulic performance.

This invention relates to water cooling systems including a dry cooling tower comprising a tower shell generallycircular in plan and a plurality of coolers arranged inside the shell around and below the base thereof for cooling water by indirect heat exchange with air induced to flow through the coolers.

According to the invention, in such a system the said coolers are grouped in a plurality of sectors each of which comprises a plurality of horizontally-extending rows of coolers, the said rows being at different levels, and a plurality of pairs of water mains each comprising an inlet main and an outlet main wherein the coolers of each said row in each said sector are connected in common with a separate said pair of mains.

One water cooling system in a preferred form according to the invention, for a condensing steam turbine plant, will now be described by way of example and with reference to the accompanying drawings of which:

FIG. 1 is a simplified half-sectional elevation of an ellipsoidal dry cooling tower forming part of a steam power station, the remainder of which is inside the tower;

FIG. 2 is an enlargement of part of FIG. 1 showing an end elevation of one sector of coolers forming part of the water cooling system; and

FIG. 3 is an enlargement of part of FIG. 1 showing some of the pipework connections and supporting arrangements of the coolers.

An ellipsoidal cooling tower 10 comprises a shell 11 supported through a ring beam 12 on a number of spacedapart legs 13. Through a hole 14 in the top of the shell 11 there projects the chimney 15 of a steam power station 16 located within the tower 10 and including a condensing steam turbine plant (not shown) which itself includes a steam condenser. The condenser may be a surface condenser or it may be a jet (or direct-contact) condenser.

The condenser drains through a number of hot-water culverts 17 (FIG. 2) to a corresponding number of sector valves 18, each of which is arranged to control the flow of hot water from the condenser through a sector or group 19 of coolers 20, and back through the sector valve 18 (FIG. 2) and a cold-water conduit (not shown) to the condenser. The sectors 19, of which there are a fairly large number, are arranged inside the cooling tower 10 around its base so as to fill the opening defined by the tower legs 13.

Each sector 19 comprises a number of side-by-side groups of three double-pass coolers 2d, the coolers of each group being arranged end to end in a straight line inclined to the horizontal as is seen best in FIG. 2, so that there are three horizontally-extending rows of coolers 20. Water in the coolers 20 is cooled by indirect heat exchange with air induced to flow inwardly between the tower legs 13, through the coolers 2t) and out of the tower 10 through the hole 14.

The topmost cooler 2t) of each group is suspended from the tower ring beam 12 by means of a link 30 (FIG. 2), similar to the links 31 (in FIG. 3) by which each of the other two coolers is supported at its top ends from horizontal reinforced concrete ring beams 32, which in turn are supported on a series of reinforced concrete stanchions 33. The bottom ends of the topmost and middle coolers are supported through brackets 34 on the beams 32. Each cooler has a vent valve 35 at the highest point of its top waterbox 36. Below each of the three rows of coolers 20 in each sector there are an inlet ring main 37 and an outlet ring main 38, supported by the brackets 34 in the case of the ring mains serving the upper two rows of coolers and by brackets 39 on the ground (FIG. 2) in the case of the lowest pair of ring mains.

Each cooler is connected across the pair of ring mains immediately below it, and a walkway 40 may be provided between each row of coolers and the next.

The ring mains 37, 38 may be connected with the condenser in a number of different ways. In the example described above, one sector valve 18 has three inlet pipes 41 and three outlet pipes 42, the inlet pipes 41 and the outlet pipes 42 being connected to an outlet main 38 and inlet main 37 respectively. In another example, however, there are three sector valves 18 to each sector, each sector valve supplying one row of coolers in its sector and each sector valve therefore having a single inlet pipe 41 and a single outlet pipe 42.

It will be understood that, although FIG. 1 shows an arrangement in which the number of coolers 20 in each row is the same (the coolers in the top row therefore being wider, measured circumferentially of the cooling tower, than those in the next row, and so on), the coolers 20 may alternatively be all the same size. In this case there will be more coolers in the top row than in the middle row, and more in the middle row than in the bottom row, so that each sector 19 will not be defined by radial planes but will comprise merely a group of coolers 20 which includes at least one cooler in each row.

The shell 11 may be made of a suitable light cladding (for example, aluminium or steel sheet, or plastic sheet) on a tubular steel frame, or in any other suitable material or combination of materials. In some cases it may be of concrete, prestressed or reinforced.

In a further example, sector valves may be dispensed with and a drain tank may be arranged at a convenient point near and below the level of the condenser, each sector 19 of coolers 20 being connected with the condenser and also with the tank, the latter being between the coolers and the condenser drain.

The invention is not confined to use with ellipsoidal dry cooling towers, but may be used in any dry cooling tower in which the height of the support structure such as the legs 13, and therefore the area available for air flow, is such as to admit of a plurality of horizontal rows of coolers in each segment. Nor need the rest of the power station be inside the tower.

I claim:

1. A dry cooling tower adapted for steam turbine apparatus, the tower comprising a generally circular shell the base of which is supported clear of the ground to provide a peripheral opening, and a plurality of coolers arranged around and within said peripheral opening and extending over the height of the latter for receiving hot water from the steam turbine apparatus for indirect heat exchange with air flowing through said tower, wherein the improvement comprises the coolers grouped into a plurality of sectors, each sector having a plurality of horizontally extending rows, said rows positioned at different levels so that between them they extend over the height of said peripheral opening, a pair of Water ring mains provided for each said row, each said pair of ring mains comprising an inlet and an Outlet main both extending parallel to and adjacent the lower end of their respective row, and each cooler of each row being connected at its lower end across its said pair of ring mains, and valve means for each sector of coolers for controlling the flow of water through said sector via said ring mains.

2. A dry cooling tower according to claim 1 wherein References Cited UNITED STATES PATENTS 2,891,773 6/1959 Heller 165-125 X 3,175,960 3/1965 Kassat 165125 X 3,305,006 2/1967 Daltry 165 124 ROBERT A, OLEARY, Primary Examiner.

l5 THEOPHIL W. STREULE, Assistant Examiner.

US. Cl. X.R. 165l24

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