Desalination solution

Researchers at the UCLA Henry Samueli School of Engineering and Applied Science have developed a new water desalination and filtration system.

In a recent field study in the San Joaquin Valley in California, the mini-mobile-modular (M3) system showed that it could desalt agricultural drainage water that was nearly saturated with calcium-sulphate salts while recovering up to 65 per cent of the water, accomplishing this with just one reverse-osmosis stage.

In designing and constructing new desalination plants, creating and testing pilot facilities is one of the most expensive and time-consuming steps.

Traditionally, small yet very expensive stationary pilot plants are constructed to determine the feasibility of using available water as a source for a large-scale desalination plant.

Using the M3 system could help cut both the cost and time involved.

'In the first part of the reverse-osmosis process, 65 per cent of the water that was fed in was recovered as drinking water,' said Yoram Cohen, the UCLA professor of chemical and biomolecular engineering, who led the development team.

'We can potentially recover up to 95 per cent using an accelerated chemical demineralisation process that was also developed at UCLA.'

In addition to its use as a pilot-scale testing unit, the M3 could also be deployed to various locations and used to produce fresh water in emergency situations.

Though the system is compact enough to be transported anywhere in the back of a van, it can generate 6,000 gallons of drinking water per day from the sea or 8,000 to 9,000 gallons per day from brackish groundwater.

By Cohen's estimate, that means producing enough drinking water daily for 6,000 to 12,000 people.