Dew Point
Dew point is the temperature at which air or flue gas becomes saturated and moisture begins to condense. Operating surfaces below the dew point causes condensation, with risks of corrosion and water damage.
The dew point depends on the moisture content and pressure of the gas. In compressed-air systems a low pressure dew point ensures no water condenses downstream. In combustion, the acid dew point — set by sulphur and moisture in the flue gas — limits how far a condensing economiser can cool the gas before corrosive acid condenses on the metal. Knowing the dew point lets engineers recover heat safely and avoid wet, corroding surfaces.
Related reading
Related terms
Psychrometrics · Flue Gas Loss · Compressed Air System · P-F Curve · Thermocouple