Most of the fouling comes from the natural environement around the plant, for example: Pollen from the trees, bird droppings, or sand if the plant is in a sandy environnement.
Other fouling comes from plant pollution, for example: oil spillage, fiber dust or Limescale/calcium.
What are the effects of fouling on ACC Performances?
Most of the fouling is moved by the fan’s airflow and arrives underneath the heat exchanger creating an isolation film underneath heat exchanger. This is the first effect.
The second effects of fouling is to reduce the air flow trough the fins.
Due to these 2 effects, the heat transfer drops.
When the heat transfer in ACC drops, Vapor condensates into water slower (1). Which explain the decrease in the vaccum level in steam manifold (2). So the Vapor flow rate in the turbine drops (3).
As a result Turbine turns slower and produces less electricity (4).
As a consequence, The plant is loosing money!
To avoid this performance dropping, it’s essential to clean periodically the fin tubes. To know more about that.