Currently, it is thought that the novel coronavirus causing outbreaks of COVID-19 worldwide is not a significant risk of contaminating industrial cooling towers. Little research has been completed to date, however.
During winter operation, a cooling tower brings as much low temperature air into contact with the flowing water as the tower fan(s) will permit. The greater the flow of cold air, the colder the water temperature will become. Fortunately, when under design process heat loads, the temperature gradients that naturally occur in counterflow cooling towers prevent the mass flow of water from reaching 32°F.
For decades, cooling towers have provided an efficient means of cooling industrial process loops by providing the lowest operating temperatures available. At the same time, through the years, water-based cooling systems have evolved.
Some farms grow food,” says the soothing yet authoritative voiceover in the commercial. “This one grows fuel.” So begins a recent television commercial from ExxonMobil that brings again to the consumer consciousness the idea of growing algae for biofuel production.
Cleanliness in a cooling tower is important for several reasons. Soiling on the cooling surfaces in cooling towers reduces cooling capacity and increases the power consumption of the fans. Impurities can lead to the formation of Legionella, which can be discharged by the air movement of the fans or by the natural draft of the cooling tower.
The only way to determine if your cooling tower system is clean is Legionella testing. It gives operators and operators an opportunity to find out if their system contains high levels of Legionella. If elevated levels of bacteria are measured, owners and operators should take corrective measures to clean and disinfect the tower.
Winter layup of cooling towers can create an environment susceptible to growth and incubation of corrosion-causing bacteria. Cooling tower cleaning and maintenance prior to spring startup is recommended by OSHA to remove biofilm and prevent Legionella bacteria.
White rust, which is a combination of zinc carbonate and zinc hydroxide, shows up as white spots and bumps on a galvanized surface. It is porous and generally does not protect a steel structure. Left unchecked, leaks can form in a cooling tower basin in as little as two months in severe cases.
Goodway Technologies, Stamford, Conn., developed calculators to help facility managers determine how much descaler is required. Those responsible for maintenance of chillers, boilers, heat exchangers, cooling towers, compressors or condensers will benefit.