Sandia LabNews

Desalination, removal of arsenic to be focus of water research at Sandia for next few years

Desalination, removal of arsenic to be focus of water research at Sandia for next few years

Research in the areas of desalination and removal of arsenic in water will step up at Sandia over the next few years, the result of a $6 million allocation in the FY2004 federal Energy and Water Development Appropriations bill.

The allocation includes $3 million for desalination and $3 million for arsenic cleanup. The American Waterworks Association (AWWA) and WERC — a consortium consisting of New Mexico State University, University of New Mexico, New Mexico Tech, and DinĂ© College — will share the arsenic cleanup money with Sandia. Sen. Pete Domenici, R-N.M., secured the funding as chairman of the Senate Energy and Water Development Appropriations Subcommittee.

"Water issues are some of the most pressing and ominous facing New Mexico and the West, and that is not likely to change anytime soon," says Domenici. "I have worked to provide the resources needed to harness the expertise at Sandia and other agencies to find better, more affordable ways to provide new resources of affordable potable water."

Tom Hinkebein, Manager of Geochemistry Dept. 6118, says that both desalination and removal of arsenic in water are important to the economies of New Mexico and the country.

"Many areas of the US are experiencing water shortages, and desalination of brackish water will provide much needed additional water," he says. "Also, new EPA standards for drinking water, which reduce allowable amounts of arsenic in drinking water, make research in the field essential."

The $3 million in support of the desalination research is consistent with the Desalination and Water Purification Technology Roadmap developed in partnership with the Bureau of Reclamation last year. Tom was the roadmap’s editor.


Tom says the desalination program will focus on the development of novel research projects. These projects can be tested at the Tularosa Basin National Desalination Research Facility in Alamogordo, now beginning construction. In 2002 Congress appropriated funds to Sandia and the Bureau of Reclamation to develop a conceptual design for the facility. The Bureau has been responsible for the engineering design and construction.

With the conceptual design "90 percent completed, it’s ready to go," Tom says. Groundbreaking for the research facility is set for June 29 with completion scheduled for March 2005.

Mike Hightower (6202), the Sandian heading up the project, says the facility will focus on research and development of technologies addressing the technical, economic, and environmental issues associated with the treatment and utilization of inland brackish groundwater.

Several entities that fund desalination research, including Sandia, the Bureau of Reclamation, Office of Naval Research, and others, will use the facility to study new desalination technologies, salt concentrate management and reuse technologies, and use of renewable energy in the desalination process.

"Current emphasis has been in developing new technologies for removing salt from brackish water," Mike says. "But equally important is what to do with the salt once it is removed."

For example, if brine water contains a ton of salt per one million gallons of water and if a plant desalinizes 10 million gallons of water a day, some 10 tons of salt is generated a day.

This is not a problem in coastal communities because salt can be returned to the ocean. Inland, it becomes an issue because locations or methods to dispose the salt may not be available. For this reason, a major part of research at the facility will focus on concentrate management.

Another area of research at the facility will be using renewable energy to power the desalination.

"One of the biggest costs of desalination is energy," Mike says. "For that reason it is important that alternate ways to power these processes be developed."

The Tularosa Basin in south-central New Mexico was selected as the desalination facility location because it contains a range of brackish water — from almost fresh to twice as salty as sea water, all within a five-mile radius. A set of wells has already been drilled at different brackish levels in the basin.

The desalination facility will consist of six indoor bays where testing can be done side by side. Testing will also be conducted outside in three additional test pads.

Tom says the goal of the facility is to ultimately "improve economics of water production to meet expanding regional needs.

"This includes both quality and quantity concerns," he says. "Water desalination will be important, not only to southern New Mexico, but also West Texas, Arizona, Nevada, and California."

Arsenic removal

The $3 million for research of arsenic removal from water stems out of new Environmental Protection Agency guidelines. The revised standards, which go into effect in 2006, change the allowable amounts of arsenic in drinking water from 50 parts per billion gallons of water to 10 parts.

"Many areas of the country are going from having no treatment of water to now having to do advanced treatment," Tom says. "Small and large communities alike will have to adapt to the new standards."

Albuquerque is one of the many communities affected by the new ruling. Arsenic concentrations in drinking water in the area are highly variable but average around 20 parts per billion.

"The intent is to develop a ‘Home Depot’ approach to water cleanup," Tom says. "By 2008 we will have the technologies ready for the utilities to buy and install."

One of the best methods is the use of adsorbants, man-made materials that have been designed for the purpose of cleaning up arsenic. The material is placed in big vessels over which water is flowed. The arsenic adsorbs into the material and water comes out arsenic free.

Sandia researchers have already developed one type of adsorbant that has been shown to work, the Specific Anion Nanoengineered Sorbents (SANS). Others are also being researched.

Development of the new arsenic removal technologies is the responsibility of the American Water Works Association. Sandia’s role will be to pilot promising new technologies as they get close to commercialization. WERC will transfer the technologies to companies that will commercialize them and sell them to the water utilities.

Malcolm Siegel (6118) is the project manager.

Tom says that besides the $3 million for the arsenic project, Sandia will soon be receiving an additional $1.8 million for other arsenic program research.

"The strict arsenic standards that take effect in 2006 are placing a tremendous burden on rural communities that simply can’t afford to meet the standard," Domenici says. "With this appropriation, we are investing in scientific expertise at Sandia to try to develop technologies that will allow the standards to be met in the most cost-effective manner."