Certain gases, principally oxygen,O , and carbon dioxide, CO , dissolved in water
accelerate its corrosive properties. The rate of corrosion is approximately in prportion to the
quantity of gas dissolved. The removal of gases from water, as practiced in steam station, is
effected by mechanical and thermal treatment , by addition of chemicals, or by combinations
of these processes, The most widely practiced method is to heat the water in either open or contact heaters, or in the more efficient types of heaters known as (deaerators). Removal of oxygen and free carbon dioxide protects piping and pumps, as well as boilers and condensate return lines from these corrosive gases
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