Mining Water from Desert Regions

desert gypsum

Image from jared

A desert probably isn't the first place you'd think to look if you wanted to find freshwater. Yet Peter van der Gaag, a researcher with the Holland Innovation Team in The Netherlands, thinks gypsum, a rocky mineral found in abundance in arid regions where oil and gas fields are common, could provide one ready source. Gypsum is 20 percent water by weight. While mining gypsum for minute quantities of water would typically constitute a difficult, relatively energy-intensive task, van der Gaag believes the unused energy given off by oil well flare-offs could be harnessed for this purpose. In addition to providing a significant source of drinkable water, the gypsum-derived water could be used to improve irrigation and, in some cases, make deserts fertile. A large-scale project could tap the billions of cubic meters of gypsum found in these regions, potentially yielding trillions of liters of freshwater.

Flare-offs could provide more than enough heat to free the water from gypsum, according to van der Gaag. "Dehydration under certain circumstances starts at 60 Celsius, goes faster at 85 Celsius, and faster still at 100 degrees. So in deserts - where there is abundant sunlight - it is very easy to do," he explains.

The process of liberating the water itself would yield bassanite, a mineral residue form of low volume, which would cause local subsidence and, therefore, help create a reservoir. Trials have so far proven successful, and van der Gaag's team is now planning on holding demonstrations in desert regions.

This obviously isn't the most practical (and time-tested) way of obtaining more water, but, if it even yields a fraction of what van der Gaag proposes, could provide one useful strategy.

Via ::ScienceDaily: Untapped Energy From Oil Flare-offs Can Be Used To Release Water Locked In Gypsum
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