September 13, 2005
Scientists Study How to Clean Salty Water
ALBUQUERQUE, N.M. (AP) -- Scientists from Sandia National Laboratories have started a study to investigate how to best clean salty water to make drinking water.
Working with the Bureau of Reclamation and other groups they are hoping to find new ways to improve the water situation in the West.
If people could drink brackish, or salt-saturated groundwater, New Mexico's water situation would be "quite rosy," said Patrick Brady, a scientist at Sandia labs.
Right now, it costs about twice as much to clean contaminated water to drinking water standards as it does to collect fresh water.
But as the population grows, the added cost could become economical, Brady said.
In New Mexico, there is about twice as much brackish groundwater as there is fresh groundwater, Tom Mayer, a Sandia scientist said.
Mayer said scientists are studying improving reverse osmosis to clean the water. In the process, water contaminated with minerals or organic material is squeezed through a filter that stops all particles bigger than the water molecules from passing through.
Sandia scientists are looking for better materials to make the filter and have tested some prototypes.
They plan to test more at the Bureau of Reclamation's Tularosa Basin Desalination Facility in Alamogordo once it's completed in 2006.
"We're set up to be a major research facility for the world, really, in this area," said Tom Jennings, manager of the facility.
Scientists are trying to lower the costs of reverse osmosis. The costs already have declined from $14 per thousand gallons 15 years ago to about $2 per thousand gallons today.
One promising idea is to create a new type of filter that mimics human cells. Such a membrane could selectively filter harmful particles from water while keeping healthy minerals intact.
"That's a science called biomimesis," Brady said.
Human cells are about 1,000 times more effective than reverse osmosis filters in pumping water out of saline solution.
"If we could come up with a technology that works like that, at even a fraction of that level, the cost to clean water would come down dramatically," Brady said.