Air - Moisture Holding Capacity vs. Temperature
The moisture holding capacity of air increases dramatically with increased temperature as indicated in the diagrams below.
Air Moisture Holding Capacity - SI Units
Moisture holding capacity of air - kg water per kg dry air:
Air Moisture Holding Capacity - Imperial Units
Moisture holding capacity of air - lb water per lb dry air:
Moisture holding capacity of air - lb water per 1000 cubic feet dry air:
Note - the moisture holding capacity of air at 100oF (38 oC) is 10 times the moisture holding capacity of air at 30oF (~ 0 oC). This is a very important observation - especially when working with drying processes where air is used to transport moisture away from process and products.
In general
- it is in general good energy economy to increase the air temperature in a dryer as much as possible! - the increased moisture transport capacity of air at higher temperature out-weights the increased energy-consumption for heating the dry air to higher temperature!
Related Topics
• Air Psychrometrics
Moist and humid air calculations. Psychrometric charts and Mollier diagrams. Air-condition systems temperatures, absolute and relative humidities and moisture content in air.
• Steam and Condensate
Design of steam & condensate systems with properties, capacities, sizing of pipe lines, system configuration and more.
• Thermodynamics
Calculate heat, work, temperature and energy. The thermodynamics of steam and condensate systems. Water and Ice properties.
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