BAA increases the use of ozone water treatment for cooling towers at Heathrow Airport
BAA has replaced chemical water treatment on cooling towers at Heathrow Airport with ozone water treatment. The systems were supplied by Waterwise Technology as part of work to upgrade and increase the capacity of the cooling towers on Terminal 3 and adding additional cooling towers to Terminal 1. The selection of these ozone system follows several years’ practical experience with similar systems supplied by Waterwise for Terminals 1 and 3. Replacing conventional chemical treatment systems with ozone eliminates the need to store and handle large quantities of potentially hazardous chemicals in the terminal areas. The protection against legionella and other bacteria is said not to be compromised. The ozone is produced electrically from air and ensures the systems are disinfected continuously with the minimum of attention. The cooling systems also incorporate Cobra Cylone side-stream filtration units, pond-purging eductors and specially designed sloping sumps in the cooling towers to provide continuous on-line cleaning and removal of dirt. This arrangement means that cooling-tower fill packs do not need to be removed annually for cleaning.