ABSTRACT
A peripheral understanding of water is essential for any boiler engineer. The aim of this chapter is to provide such a simplifi ed overview.
Both water and steam tend to dissolve some amounts of material they come in contact with, forming oxides, hydroxides, hydrates, and hydrogen. To protect the equipment, it is essential that water chemistry is controlled. This is done in two stages. Water is fi rst subjected to treatment to make it suitable for admitting into the boiler. In the second stage, its dissolved gases are removed and it is turned alkaline as required to convert it into feed water (FW). In its passage from FW to boiler water and thereafter to steam, water is conditioned suitably by dosing various chemicals at appropriate places to prevent it from (1) forming scales, (2) causing corrosion, and (3) contaminating steam.
