Cooling tower with fire stop
A cooling tower with a plurality of fill packs has a fire stop with openings disposed below the fill packs, a water distribution system for distributing water onto the fill packs, and a cold water basin disposed below the fire stop for collecting water which has past through said fill packs. The openings in the fire stop occupy at least 80% of the area over which the fire stop extends. The fire stop is made of an intumescent material with an expansion ratio sufficient to close said openings when said material intumesces.
1. A cooling tower comprising:
a plurality of fill packs;
a fire stop with openings, said fire stop disposed below said fill packs;
a water distribution system arranged for distributing water onto said fill packs;
a cold water basin disposed below said fill packs and said fire stop for collecting water which has past through said fill packs;
said fire stop extending over an area, said openings in said fire stop occupying at least 80% of said area;
said fire stop comprising an intumescent material with an expansion ratio sufficient to close said openings when said material intumesces.
2. The cooling tower of claim 1 wherein said fire stop comprises a composition containing said intumescent material and a thermoplastic material.
3. The cooling tower of claim 2 wherein said fire stop is configured as a grid.
4. The cooling tower of claim 3 wherein said fill packs are arranged into layers of said fill packs.
5. The cooling tower of claim 4 wherein a lowermost layer of said layers of fill packs rests on said grid.
6. The cooling tower of claim 3 wherein said fill packs are supported by said grid.
7. The cooling tower of claim 4 wherein said grid is an intumescent grid and further comprising a support grid, said intumescent grid resting on said support grid, said openings of said intumescent grid aligned with openings through said support grid.
8. The cooling tower of claim 4 wherein said grid is a first grid and further comprising a second grid comprising a composition of said intumescent material and said thermoplastic material, said second grid disposed between two adjacent layers of said fill packs.
9. The cooling tower of claim 8 further comprising a fire retardant blanket extending along at least one outer side of said layers of fill packs.
10. The cooling tower of claim 4 further comprising a frame and wherein said grid is supported by said frame.
11. The cooling tower of claim 3 wherein said intumescent material is between 5% and 55% by weight of said composition.
12. The cooling tower of claim 11 wherein said thermoplastic material is between 30% and 60% by weight of said composition.
13. The cooling tower of claim 12 wherein said thermoplastic material is polyvinyl chloride.
14. The cooling tower of claim 3 wherein said intumescent material is an expandable graphite.
15. The cooling tower of claim 3 wherein any given opening has a width that is a multiple of a width of grid walls on opposed sides of said any given opening and wherein said intumescent material has an expansion ratio at least equivalent to said multiple.
16. The cooling tower of claim 4 wherein said openings of said grid are square-shaped.
17. The cooling tower of claim 16 wherein said grid walls have a width of ⅝″ (1.6 cm) to 2″ (5.1 cm).
18. The cooling tower of claim 17 wherein said intumescent material has at least a tenfold expansion ratio.