Fresh water production from/by atmospheric air for arid regions, using solar energy: Review
The Atmospheric air is considered a huge and renewable source of fresh water. The atmosphere contains about 12,900 km3 of fresh water, whereas liquid water resources of inhabited lands is about 12,500 km3.In this paper, atmospheric water vapor processing (AWVP) technology is reviewed. These processors are machines which extract water molecules from the atmosphere, ultimately causing a phase change from vapor to liquid. Three classes of machines have been proposed. These classes are either cool a surface below the dew point of the ambient air, concentrate water vapor through use of solid or liquid desiccants, or induce and control convection in a tower structure. The review is extended to cover different humidification and dehumidification (H–DH) techniques in which air is used as a medium to carry water in the form of vapor. The study concentrates on the extracting potable water from air especially with respect to the remote/rural arid places. Finally, different technological processes to extract water from the ambient air using solar energy as a power source are focused with discussing their strengths and limitations.