Water is used in cooling systems as a heat transfer medium and frequently also as the final
point to reject heat into the atmosphere by evaporating inside cooling towers. Depending on the
quality of available fresh water supply, waterside problems develop in cooling water systems
from:
• Dirt and dust accumulation
• Biological growth
Any of these problems – or more usually a combination of them – result in costly unscheduled
downtime, reduced capacity, increased water usage, high operation and maintenance costs,
expensive parts replacements, and acid cleaning operations which reduce the life of the cooling
system.
There is no single method of treating cooling water. Selection of water treatment program for a
specific system depends on:
1. System design, including system capacity, cooling tower type, basin depth, materials of
construction, flow rates, heat transfer rates, temperature drop and associated accessories
2. Water, including make up water composition / quality, availability of pre-treatment and
assumed cycle of concentration
3. Contaminants, including process leaks and airborne debris
4. Wastewater discharge restrictions
5. Surrounding environment and air quality
In this course, we will discuss the reasons and means for controlling scale, corrosion and
biological fouling.
Critical Parameters
The critical parameters for cooling water are: conductivity, total dissolved solids (TDS),
hardness, pH, alkalinity and saturation index.
