By problem
Boiler scale is a hard layer from hardness and silica in the feed water. The layer forms on the hot surface. Scale blocks heat transfer to the water. The boiler burns more fuel, and the tube metal gets too hot.
By problem
An open cooling tower contacts the air. Evaporation concentrates hardness and silica. Scale and corrosion block heat transfer. Algae, biofilm and bacteria block the fill.
By problem
Water in a closed heating or cooling loop is replaced rarely. If oxygen, pH and bacteria are not controlled, the metal corrodes. Iron oxide sludge, also called magnetite in plant use, blocks narrow passages.
By problem
A reverse osmosis membrane leaves the salt behind. When the remaining hardness and silica pass saturation, scale forms on the membrane. Organic dirt and biofilm are a separate fouling. The antiscalant and the dosage are selected from the feed water analysis and the projection report.