The use of ozone as a maintenance treatment for cooling towers has good potential for operation and maintenance savings in the Federal secior. A small amount of ozone acts as a powerful biocide thai decreases or nearly eliminates the need to remove quantities of water from the cooling tower in order to decrease the concentration of organic and mineral solids in the system. Ozone treatment can also reduce the need for chemical additives added to the cooling tower water.
In a properly installed and operating system, bacterial counts are reduced, with a subsequent minimization of the buildup of biofilm on heat exchanger surfaces. The resulting reduction in energy use, increased cooling tower operating efficiency, and reduced maintenance effort provide cost savings as well as environmental benefit and regulatory compliance with respect to discharge of wastewater from blowdown.
Cooling towers associated with chillers for air-conditioning are good candidates for ozone application.
Ozone may be a corrosion stimulant rather than an inhibitor, and this can be a factor in some circumstances. Nevertheless, it is easier to combat corrosion in a clean system than in one that is biologically and mineralogically fouled.
This Federal Technology Alert (FTA) provides detailed information and procedures that a Federal energy manager needs to evaluate most cooling tower ozone treatment applications. The New Technology Demonstration Program (NDTP) technology selection process and general benefits to the Federal sector arc outlined. Ozone treatment, energy savings, and other benefits are explained. Guidelines are provided for appropriate application and installation. Two actual case studies are presented to give the reader a sense of costs and energy savings. Current manufacturers, technology users, and references for further reading are included for prospective users who have specific or highly technical questions not fully addressed in this FTA