UCLA researchers combine techniques into new technology to create drinking water from the sea
By alessandra daskalakis
Sept. 29, 2011 12:40 a.m.
Correction: The original version of this article contained an error. Yoram Cohen arrived at UCLA over 30 years ago.
Sitting on Yoram Cohen’s desk is a bottle filled with water that once belonged in the ocean.
“It tastes great,” said Cohen, a professor of chemical and biomolecular engineering at the UCLA Henry Samueli School of Engineering and Applied Science. “It’s the best-tasting water ever.”
He said it with a chuckle. That water bottle, however, represents years of research by Cohen and his colleagues in transforming dirty, salty or otherwise contaminated water into a drinkable liquid.
The team has developed technology called compact modular reverse osmosis technology. The system combines two water technology techniques, ultrafiltration and secondary reverse osmosis, to create 18,000 gallons of drinking water from the sea per day.
That amount of water is roughly enough to provide for the population of UCLA, Cohen said.
Still in testing, the system could ultimately allow Southern California to reduce its reliance on imported water, Cohen said. He said the system is in some ways cheaper than bottled water, as it may cost only $1.50 for 1,000 liters of water, compared to $3 for 1 liter of bottled water.
Cohen said he is planning to work with the UCLA cogeneration plant to develop a similar system that would decrease water waste and increase water availability on campus.
During the past two years, the team has pushed to move its work from the laboratory to real-life applications, Cohen said. The second generation of the technology is currently being tested in coordination with the U.S. Navy to turn sea water into drinkable water.
When he arrived at UCLA 30 years ago, Cohen’s office was one door away from the faculty who revolutionized water technology in the 1960s by creating the first reverse osmosis membranes for desalination, he said.
The experience of working one door away from these scientists influenced his research, but Cohen said the push to get involved in this area of study did not occur until California began experiencing more global climate change and water problems.
They are also working to create a simplified, commercial model of the water cleaning technology that will work with various salinity levels and needs, said Larry Gao, a second-year chemical engineering graduate student in charge of the electrical aspects of the project. The system will be tested in the San Joaquin Valley.
“The most rewarding aspect (of the project) is that all this theoretical work has found its way into application,” said Panagiotis Christofides, a professor of chemical and biomolecular engineering at the School of Engineering.
Christofides is responsible for the development of the controls to ensure the system can function without much oversight.
Cohen gave high praise to the students involved in the project. The work is an opportunity for practical application of research, said postdoctoral student Andi Rahardianto.
“It’s very rewarding and very rare when you get this opportunity where what you do in the lab works in the field and people can see it,” Rahardianto said.
