Thermodyne Boilers Industry Blog

Corrosion is a phenomenon   in which atmospheric oxygen in the air or water reacts with the metal to form oxides.   Corrosion in industrial boilers   is a phenomenon in which the oxygen that is dissolved in the water inside the boiler reacts with the metal of the boilers. Ferrous component of the metal reacts with the atmospheric oxygen in the water to undergo oxidation. This oxidation results in the formation of ferrous oxides. Ferrous oxides lead to the formation of cavities and holes in the metal. This gradual formation of cavities and holes in the metal is termed as pitting. Pitting is the main host for the corrosion which ultimately destructs metal and its properties. Causes of Corrosion Improper and unscheduled maintenance. Exposure of boiler metal to dissolved gases present in boiler water Oxygen present in boiler water Carbon Dioxide present in boiler water Unbalanced pH of boiler water Improper and unscheduled maintenance Exposure of metal to the ...

Corrosion is the gradual deterioration of metals by chemical reactions with their environment. Effects: 1. Pinpoint penetration of metal 2. Rusting of ferrous metals 3. Pits can penetrate deep into the metal that can result in rapid failure of feed lines, economiser tubes and boiler tubes 4. Ultimate failure of boiler metal, steam mains and condensate lines Causes: 1. Dissolved oxygen in boiler water. 2. Presence of corrosive gases such as Oxygen (O2), Carbon Dioxide (CO2), Hydrogen Sulphide (H2S) in the boiler water 3. Sludges of bicarbonate and carbonate 4. Low PH 5. Low feed water temperature 6. Acidity imparted to water due to decomposition of Carbon Dioxide (CO2) or Hydrogen Sulphide (H2S) PREVENTIVE MEASURES: 1. Eliminating corrosive gases 2. Removal of dissolved oxygen 3. High PH value of boiler water 4. Mechanical deaeration of boiler water 5. Higher feed water temperature i.e. reduces its oxygen content. 6. Chemical de-oxygenation by use of oxygen ...