Cooling Towers


Cooling water treatment is required to control the risk of legionella as identified by HSE guideline “Legionnaires’ disease: The control of legionella bacteria in water systems”. Regular maintenance and assessments of cooling water systems will reduce the risk of buildup of corrosion and bio fouling of the system that can occur if untreated. Legionella and various other harmful bacteria will thrive and breed in such conditions making the water system unsafe to use due to dangerous environmental risks. Additionally the lifespan of the system will suffer if inadequately maintained.

To minimize the risk of such microbial activity, Enviroliance can offer management and maintenance for your cooling towers in order to operate at maximum efficiency.

Cooling tower services:

  • Legionella Risk Assessment
  • Legionella sampling and analysis
  • Chemical Clean and Disinfection
  • Monitoring and Maintenance

Further information regarding cooling towers:

Bleed off Control

An evaporative cooling system is used to cool down a process by the evaporation of water to release energy in the form of heat out of a cooling tower. The process works as heat is transferred through a heat exchanger from the process material to the pure water that is evaporated. As the pure water and not the minerals present in the process material is evaporated from the system, as the volume of evaporated water increases so does the concentration of minerals present in the system. An increase in mineral content of the system can cause scale formation inside the cooling tower. To avoid scale formation, the water should be bled off and replaced with water that has a lower concentration factor of minerals.

Scale Formation

Minerals are likely to accumulate in an evaporating cooling system when the concentration factor in the process material is high. Deposits of minerals such as magnesium and calcium salts can lead to the formation of solid scale and lime scale substances inside the cooling tower. Buildup of scale in the system is detrimental to the efficiency of the cooling tower as the heat exchanger component becomes inhibited. Scale in the system also poses a threat to the quality of water control as it acts as a breeding ground for harmful bacteria such as Legionella.

Filler Pack

The filler pack component of an evaporative cooling system is often the most common source of bio fouling. Enviroliance can offer a full clean and disinfection of filler pack components to ensure the water quality of the cooling tower is maintained. The filler pack is a honeycomb mesh structure that provides a large surface area for the evaporated water to cool. Algae, moss and fungi can grow on the mesh forming microbial slimes inside the cooling tower. This bio fouling of the cooling tower from the presence of slime affects the quality of water control. One way in which Enviroliance can eliminate bio fouling from a system is through the use of corrosion inhibitors. Corrosion inhibitors are introduced into a system to reduce the formation of rust and eliminate any possible source of nutrient from which the microorganisms can feed off.