Cooling towers are one of the most common water recycling technologies in use by industry today. By taking advantage of water’s high heat of evaporation, cooling towers offer effective and relatively inexpensive cooling for a wide range of industrial uses. 2/3 industrial water is used for cooling water (removal of heat). In some industries such as electric power plants or oil refineries, even up to 90% of intake water is used for cooling. Cooling water is easy to treat and sometimes even of quite a good quality. It can therefore easily be reused for example for washing processes. However, once used for washing and eventually contaminated, an appropriate treatment system before reuse is required.