Commercial and industrial (mechanical) cooling systems have become commonplace throughout
the United States and the world over the last 60 years. Improved indoor environments due to air
conditioning systems enhance the productivity of millions of workers around the world. In
addition, commercial and industrial refrigeration systems lengthen the shelf life of perishable
foods, minimizing exposure to harmful bacteria and spoilage, thereby allowing the transportation
of these foods over vast distances. Industrial cooling systems help make many processes and
products possible we normally take for granted. Since the advent of the ammonia and vapor
compression refrigeration cycles, these systems have become an increasingly more important in
numerous aspects of our daily lives even though we are largely unaware of their presence.
The largest and most efficient cooling systems use water to cool the refrigerant in ammonia and
vapor compression cycles. Evaporated water carries away the heat necessary to do this.
However, much water is wasted in the controlling of solids concentrated in the cooling water left
behind. Water supplies vary in quality from site to site, primarily in the amount and type of
dissolved solids which, in turn, require a customized chemical selection and water treatment
strategy. In certain areas, chemical treatment against scale formation only seems to have a
marginal effect, thus necessitating frequent cleaning of heat exchange surfaces. This is true
even though the science of chemical water treatment has improved. Leaving the application of
chemicals to the discretion of the water treatment specialists, who may or may not have the
knowledge to treat a condenser water systems, rarely maximizes water efficiency.
This paper discusses several available technologies that improve the treatment of condenser
water, thereby reducing the amount sent to the drain (sewer). Technologies include chemical
water treatment, which is the traditional and accepted approach to condenser water treatment,
and some newer, non-chemical technologies that approach this important area quite differently
than traditional methods. We focus on those technologies that have shown the best track record
for long-term water efficiency and successful operation.
Appendix A provides additional background information regarding cooling systems, which will
help readers to become acquainted with the various technologies and industry terminology.
Appendix B concentrates on water treatment technologies and terminologies.