Dew Point Temperature
Definition - What does Dew Point Temperature mean?
Dew point temperature is the temperature wherein air is no longer capable of holding the water vapor that is contained within it. At the dew point temperature, water vapor condenses into liquid water. At all times, the dew point temperature is equal to or less than the air temperature.
A thorough knowledge about dew point temperature is very important in various industries because moisture can affect corrosion rates.
Corrosionpedia explains Dew Point Temperature
In oil plants, it is essential to prevent processes such as condensation to ensure that surfaces that are close to combustion gases do not go below the acid dew point temperature. It is a low temperature that causes emission of acid smut as well as corrosion.
For instance, if a fuel that is sulfur free is combusted with around 30% excess air, moisture starts to condense out at a temperature of 113°F (45°C). This is referred as water dew point. If a fuel with sulfur is burned under similar conditions along with water dew point, acid dew point takes place at about 240°F (116°C).
During the combustion process, the sulfur contained in fuel undergoes oxidation. This leads to acid dew point, which is the highest level of temperature where acid deposition can take place.
Therefore, appropriate operation surface temperatures in industries such as oil plants should be maintained to prevent acid smuts that could cause potential damage such as corrosion.