Tempered Water Systems

The cold-water supply for the tempered water system will be ordinary cooling water. No attempt will be made to keep its temperature constant. The hot-water temperature will be maintained constant by opening and closing the steam input to the hot-water storage tank. Close control is not necessary. 

A tempered water system has been specified for the reactor. It will be assumed that a 10°F rise in cooling water temperature is typical. Using data from the Case Study section of Chapter 5. 

The tempered water system on the reactors will flow control system. 

Some circulating water systems are maintained in a closed loop called a tempered water system. Since the water does not travel through a cooling tower, oxygen, which could cause corrosion, does not enter the system. Still, biocide treatment may be necessary since many corrosion-causing bacteria are anaerobic. —... 

Because cooling water consumption is governed by factors other than energy conservation and because cooling water velocities must be maintained above certain values, tempered water systems can be effectively used at locations where cooling water temperatures vary with the season of the year. At some locations a 30°C difference between summer and winter water temperatures is experienced. At such locations a tempered water system may be used... 

Throttling cooling water flow to water-cooled condensers is generally not recommended because of fouling and silting which frequently occur at reduced water velocities. Consequently, water-cooled condensers should be provided with tempered-water systems as described in Chapter 13. Tempered-water systems result in better control, reduced maintenance, and reduced pumping costs. 

Install a tempered-water system. The necessary equipment would be provided to heat water which in turn would heat the process. 

Tempered water systems blend hot and cold input water to maintain a prescribed temperature through a full duty cycle. 

Some auxiliary equipment is required to create a vacuum and separate the methanol and water removed from the product in the vacuum and condensate collection system (see Figure 11.9). These auxiliary systems include a steam ejector vacuum system, peroxide treatment system, and tempered water system. 

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