Wet-dry cooling

Figure 5. Single structure type wet-dry cooling tower.

Present State of Development of Combined Wet/Dry Cooling in the Federal Republic of Germany and Initial Operating Experience with Different Processes)... 

The paper makes a comparison between separate-structure wet/dry cooling towers with different condensers or the same condenser and with parallel or series circulating water flow. The use of single-structure versus separate structure wet/dry towers is also considered. 

Wet/Dry Cooling Tower An Effective Plume Control Method... 

Under certain conditions, the exhaust air of conventional mechanical draft cooling towers may form a fog plume, causing visibility and icing problems to highways and equipment. In cases where this cannot be tolerated, a combination wet/dry cooling tower is shown to be effective fog plume control method. The paper describes the basic phenomena of cooling tower fog formation. The operation and performance characteristics of the wet/dry tower are discussed as well as a method of select wet/dry design criteria. 11 refs, cited. 

Dry and Wet/Dry Cooling Towers for Power Plants Webb, Ralph L. (Ed.) Barry, Robert E. (Ed.)... 

Considerations Required for the Optimum Design of a Wet-Dry Cooling Tower with Respect to Minimizing (Cost and) Visible Vapor Vodicka, V. Henning, H. 

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. 

Wet-dry cooling towers incorporating these designs are being used for large-tower industrial applications. At present they are not available for commercial applications. 

Water Conservation Applications— et-Dry Cooling A modified and hybridized form of a WSAC can be used to provide what is called wet-dry cooling for water conservation applications (Fig. 12-8p). A hybridized combination of air-cooled dry finned tubes, standard wetted bare tubes, and wet deck surface area permits the WSAC to operate without water in cold weather, reducing water consumption by about 75 percent of the total for an equivalent CT application. 

The use of water is discontinued after ambient dry-bulb temperatures fall below the switch point temperature, since the entire process load can be cooled using only cold fresh ambient air. By using this three-step load-shifting practice, total wet-dry cooling water consumption is about 25 percent of that consumption total experienced with an equivalent CT application. 

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