MILAN – Straight from Egypt, the latest concept addressing the serious problem of world water shortage: a study conducted by researchers at Helwan University (Cairo, Egypt) who have developed a system of extracting water from damp air. Water issues particularly affect those zones where less developed countries are located and are due to either natural causes, like drought, or the activities of man, like pollution and poor management of water resources.
The system
The system uses calcium chloride (a desiccant) to capture water vapour. The liquids are then released using solar energy and collected in a tank. It all costs virtually nothing. This innovative system can be used to obtain water even in the most remote areas of the planet. It is a system designed for the benefit of activities like agriculture or livestock farming, which require large quantities of water to be at their disposal. The terrible scourge of water shortage not only directly affects the population, but also the economy and wellbeing of society. To extract water from the air, it must be cooled to a sufficiently low temperature (dew point) and then the liquid formed is collected. Alternatively, it is possible to collect water with any appropriate desiccating substances which absorb water vapour on their surfaces. These substances are subsequently heated to collect the liquids. The main disadvantage of these methods is that they do not use renewable resources and require high quantities of energy, either to chill the air, or to heat the desiccating materials.
Addressing the problem
To try and resolve this problem, scientists and engineers have developed techniques for making water more available: the treatment and purification of polluted water, for example, enabling liquids to be made usable for agriculture. The desalination of seawater and other methods can supply fresh water for irrigating fields, but even this process is rather costly in that it requires a great deal of energy.
by editorial staff
