Cooling tower recirculation

Guidelines for Cooling Tower Recirculating Water (Normal Limits for Using Film Fill)... 

Interference is defined as an adulteration of the atmosphere entering the tower by a portion of the atmosphere leaving another nearby cooling tower. Recirculation is an adulteration of the atmosphere entering the tower by a portion of the atmosphere leaving the tower. Both are illustrated in Figure 6.8. 

Developing Cooling Tower Recirculation Factors from Field Test Data Baker, D. R. 

Removal of Particulate Matter. The amount of particulate entering a cooling system with the makeup water can be reduced by filtration and/or sedimentation processes. Particulate removal can also be accompHshed by filtration of recirculating cooling water. These methods do not remove all of the suspended matter from the cooling water. The level of fouling experienced is influenced by the effectiveness of the particular removal scheme employed, the water velocities in the process equipment, and the cycles of concentration maintained in the cooling tower. 

Some use is being made of lower grade heat sources, such as moist air from driers, and the constmction of auxiHaries, such as condensers, integral with the evaporator body. A further step is elimination of the conventional condenser—cooling tower—vacuum pump circuit by recirculating last-effect Hquor over the equivalent of a cooling tower built as an integral part of the evaporator body. 

Example 9-16 Wood Packed Cooling Tower with Recirculation, Induced Draft... 

Open recirculating systems These are more amenable to inhibition since it is possible to maintain a closer control on water composition. Corrosion inhibition in these systems is closely allied to a number of other problems that have to be considered in the application of water treatment. Most of these arise from the use of cooling towers, ponds, etc. in which the water is subject to constant evaporation and contamination leading to accumulation of dirt, insoluble matter, aggressive ions and bacterial growths, and to variations in pH. A successful water treatment must therefore take all these factors into account and inhibition will often be accompanied by scale prevention and bactericidal treatments. 

Quench waste recirculation requires installation of a cooling tower to lower the temperature of the quench wastewater stream. The multimedia filter system for the final polishing of effluent includes a backwash mechanism, pumps, control media, and the filter structure. 

Plant 1226 is a bituminous coal-, oil-, and gas-fired electricity plant [1]. The recirculator cooling water system influent was sampled from a stream taken from the river and the effluent from the cooling tower blowdown stream. The effluent stream is used again in the ash sluice stream. Table 7 presents the data. The following additives are combined with the cooling tower influent ... 

In normal operations, continuously recirculating water picks up waste heat from a refrigeration compressor or process heat exchanger, and the hot water is pumped to the top of the tower and dropped over the cooling tower. Evaporative action removes the heat from the water and adds it to the air. The hot, moist air is ejected from the fan stack, and the cooled water returns to the compressor or exchanger to pick up more heat. Figure 1.1 illustrates the cooling tower operation. 

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