Counterflow Film Fill Cooling Towers are very susceptible to fouling, which refers to the accumulation of unwanted material on the surface of the tower fill. The tower fill is a crucial part of the cooling tower as it provides a large surface area for the water to be in contact with the air. It is made up of a network of plastic sheets that allow water to flow through them, and air to flow over them, which increases the rate of heat transfer.
Fill fouling is the deposition of material on the fill’s heat transfer surfaces. It involves one or more of the following processes:
The most common fouling is caused by a combination of suspended solids deposition with biological deposits. Since modern film fills have such large heat transfer surface area per unit volume, this type of fouling can cause problems such as significant decreases in thermal performance and increases in pack weight. The former will cause a loss of system efficiency and the latter can lead to catastrophic failure of the fill support system
