Devices to remove moisture from air - dehumidification - can be classified as
- absorption dehumidifiers
- spray dehumidifiers
- refrigeration dehumidifiers
In an absorption dehumidifier moisture is extracted in a sorbent material.
The sorbent material contains a vast number of microscopic pores where water is absorbed. When the sorbent is saturated it can be dehumidified with hot air. It is an intermittent process where a more complicated control of the air flow through the humidifier is required.
As long as the temperature of water is lower than the dew point of the air flow an air washer or a spray dehumidifier can be used.
The air is dehumidified when moist in the air saturates on the surface of the sprayed water.
In refrigeration dehumidifier the airflow passes a cooled surface where some of the moist in the air saturates. The surface or coil is cooled by a refrigeration unit.
Air Conditioning systems - heating, cooling and dehumidification of indoor air for thermal comfort.
Moist and humid air - psychrometric charts, Mollier diagrams, air-condition temperatures and absolute and relative humidity and moisture content.
Basic air changing state processes - heating, cooling, mixing, humidifying and dehumidifying by adding steam or water - psychometric diagrams and the Mollier charts.
Relative humidity in moist air can estimated by measuring the dry and wet bulb temperature.
The mass of water vapor present in moist air - to the mass of dry air.
Psychrometric chart for air at barometric pressure 29.921 inches of Mercury and temperature ranging 20oF to 120oF.
Heat removed from storage rooms with cooled air.
Latent and sensible cooling and heating equations - imperial units.
Latent and sensible cooling loads to consider when designing HVAC systems.
Dehumidifying by cooling, adsorption or absorption.
Cooling and dehumidifying processes of moist and humid air - sensible and latent cooling.
The Mollier diagram is a graphic representation of the relationship between air temperature, moisture content and enthalpy - and is a basic design tool for building engineers and designers.