Cheap procedure to reuse seawater

Scarcity of water can soon be a thing of past if salty seawater is filtered by a cheap process called reverse osmosis, by making the water pass through a membrane, suggests a new research.

In reverse osmosis, a contaminated liquid is forced to pass through a semi-permeable membrane to block the most dissolved substances.

This Yale University study argues that seawater desalination could help overcome fresh water shortages.

"The...oceans are a virtually inexhaustible source of water, but the process of removing its salt is expensive and energy intensive," said Menachem Elimelech, professor of chemical and environmental engineering, who led the study.

But Elimelech and William Phillip, now at the University of Notre Dame, argue that technology based on reverse osmosis might be effective, according to a University of Notre Dame statement.

They suggest that a membrane capable of filtering out boron and chloride, minerals that occur naturally in seawater, would ensure substantial energy and cost savings, the journal Science reports.

Seventy percent of world's water is used in agriculture but water containing even low levels of these minerals cannot be used for these purposes.

Instead of removing them during a separate post-treatment stage, they believe a membrane could be developed to filter these out simultaneously with the salt.

Over a third of the global population already lives in water scarcity areas.