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Cooling towers
Cooling towers used to backup or restore the water. In one design, the hot water is pumped from the condenser to the tower. No, it is sprayed into the tower basin. The water temperature decreases, as it gives off heat of air circulating through the cooling tower. Some of the towers are rather large, so they operate with capacitors yielding to 1600 tons of cooling capacity. Cm. Fig. 8-14.
Most of cooling that takes place in the tower results from the evaporation of the water as it falls through to the tower. The lower the wet-bulb temperature of the incoming air, the more efficient air decrease in temperature of water entering the tower. The following factors influence the effectiveness of the cooling tower.
- The average difference between saturated vapor pressure, air and pressure in a water tower
- The duration of exposure and the amount of water surface is exposed to the air
- The speed of the air through the tower
- The direction of air flow relative to the exposed water surface (parallel, transverse, or counter)
Theoretically, the lowest temperature to which the water can be cooled air temperature (wet bulb temperature) entering the tower.
However, from a practical point of view, it is impossible to reach the temperature of the air. In most cases the temperature of the water leaving the tower will reach at least 7 to 10F (4 to 6C) above, the air temperature.
The range of tower-water temperature on the cooling tower and the temperature of water coming from the tower. In this range should be adapted to the operation of the condenser for maximum efficiency...
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