ABSTRACT
In addition some highly soluble materials are changed by the high boiler temperature to materials of low solubility such as calcium carbonate which are then precipitated. Much of this precipitation takes place where the boiler water is the hottest, where water is in contact with high heat transfer zones. One of the purpose of a water treatment program is to keep certain scale forming solids in solution. Other scale forming solids are turned into a soft fluffy precipitate and carried down to the low points of the boiler. Energy loss through blow-down is minimized by maintaining the boiler water cycles of concentration as close to the recommended limit as possible. This can be best accomplished by automating the continuous blow-down. Because calcium and magnesium compounds are relatively insoluble in water, they tend to precipitate out, causing scale and deposit problems. The hardness of the water source is an important consideration in determining the suitability of water for steam generation.
