Cooling tower typical performance

FIG, 12-17 Typical plot of cooling-tower performance at varying fan speeds. 

Altitude has an effect on cooling tower performance but in a unique way. Air handlers, air cooled condensers and the like are typically made to operate at higher speeds (or, with a steeper fan pitch) as altitude increases in order to maintain the... 

Debris particles that are heavier than water migrate to the outer wall area and slither down into a collection bowl that is periodically blown down. Very little water is lost. Typical performance is 97.8% of solids with specific gravity exceeding 1.2 down to 45 microns. Side stream filtration is more common in cooling tower applications. The scheme uses a small dedicated pump to draw dirty water from the sump, direct it through a filtration device and sent it back to the basin. 

Figure 9.19. Typical cooling tower performance corves (Cheremisinoff and Cheremisinoff, 1981).

Figure 7.5 Typical cooling tower performance curves for different water loadings.

This provides curves for cooling tower performance and typical off design performance of centrifugal compressor chilled water systems. These graphs show typical coincident wet and dry bulb temperatures, in... 

Typically limit to 2500 to 3500 ppm TDS maximum in the cooling system, depending on circumstances. High levels can increase the tendency for galvanic corrosion. Levels of over 5000 ppm TDS can affect thermal performance and may be detrimental to wood in alternatively wet/dry cooling tower zones, such as the fan deck and louver faces. 

Moving bed gas adsorbers also have been proposed and used, patterned after moving bed gas oil crackers. In the Hypersorber of Figure 15.28, flows of gas and solids are countercurrent in a single vessel. After saturation, the solid is stripped with steam and removed at the bottom of the tower, and gas is lifted to cooling and adsorption zones. The control mechanism for solids flow and typical performance for ethylene recovery from cracked gases also are shown with the figure. Partly because of attrition losses and the advent of competitive processes for ethylene recovery, the Hyper-... 

The performance charts. Figures 3-2, 3-3, 3-4 and 3-5, are constructed on a tower unit basis and represent the characteristics of a typical industrial cooling tower. Each chart represents performance at a constant cooling range of 7, 10,15 and 25°F,... 

Because of the extremely high heat of vaporization of water (about 970 BTU/lb, 2256 kJ/kg), only a modest reduction in temperature can be achieved in the best circumstances. Typical performance is a reduction of water temperature by 3.9°C (7°F) to 6.7°C (12°F) - from 35.0<"C (95°F) to 28.3°C (83°a The limit on achieving a higher level of cooling of water in a cooling tower is the saturation limit of water in air, which is very low. For example, the just-described performance is an increase from 0.010 to 0.020 lb water/lb dry air. 

FIGURE 16-3 A typical performance curve for a water cooling tower... 

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