When is Internal Treatment of Boiler Feed-water Necessary?
Chemical treatment of water inside the boiler is usually essential whether or not the water has been pretreated. Internal treatment, therefor, complements external treatment by taking care of any impurities entering the boiler with the feed water (hardness, oxygen, silica, etc.) regardless of whether the quant- ity is large or small. In many cases external treatment of the water supply is not necessary and the water can be treated by internal methods alone. Internal treatment can constitute the sole treatment when boileers operate at low or moderate pressure, when large amounts of condensed steam are used for feed water, or when the raw water available is of good quality.
