Correlation of dew point of dry air
Correlation of dew point of dry air
(OP)
I have a plant with a quoted ideal loading of 50mg/Nm3 of moisture in air post a drying tower. Any idea what this is in terms of the air dew point?
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Correlation of dew point of dry air
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Correlation of dew point of dry airCorrelation of dew point of dry air(OP)
I have a plant with a quoted ideal loading of 50mg/Nm3 of moisture in air post a drying tower. Any idea what this is in terms of the air dew point?
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RE: Correlation of dew point of dry air
Tranform it into a mol fraction. Multiply by the total pressure to get the moisture's partial pressure. Look for temperatures in tables of water/ice vapor pressures. I may be wrong, but my estimates for atmospheric conditions indicate a dew point of about -57oC.
RE: Correlation of dew point of dry air
However, this link Dew Point says something else.
RE: Correlation of dew point of dry air
It all depends on what is "standard" or "normal" air.
Normal: The density of dry air at 0oC and 1 ata is 1.3 kg/m3, thus, the mass concentration would be:
Standard: Dry air at 70oF and 101.325 kPa has a density of 1.2 kg/m3 resulting in a mass concentration of
RE: Correlation of dew point of dry air
Quark, sorry I wrongly read the vapor pressure table, and your finding is right. Then,
4.17*10-5 mass basis *29/18 → 67.2 ppm by vol, corresponding to a dew point of ~ -50F or ~ -46oC in the given link.
I assumed 29 and 18 for the MW of air and water, respectively.
RE: Correlation of dew point of dry air
Cheers
Trevor