“Water scarcity is intensifying in all regions of the country,” says UCLA Engineering Dean Vijay Dhir. “The need for an adequate supply of affordable, accessible, clean water is a key priority for our nation's future and for Southern California. As the birthplace of the first viable reverse-osmosis membrane in the 1960s, it is entirely fitting that the UCLA School of Engineering should continue to take this important research to the next level and beyond.”
The development of next-generation desalination technologies is critical - saline and brackish waters constitute more than 97 percent of the water in the world. Less than 3 percent of water has a salinity content that can be considered safe for human consumption, according to the National Academies' “Review of the Desalination and Water Purification Technology Roadmap.” Desalination embodies many different technologies, which are based on either thermal or non-thermal membrane-based separation methods. Reverse osmosis desalting - the removal of salt and other pollutants from water by using a membrane through which these particles cannot pass - is the most common.
The difficulty with this method is that membranes are prone to fouling by bacteria, natural organic matter and scaling by mineral salts. As a result, the lifetime of the membrane is shortened, desalination plants are forced to operate at lower water recovery levels, and that increases the costs and the issues in dealing with the waste left over from cleaning the water.
The current water infrastructure in the United States continues to degrade due to age and increasing salinity. The current salinity of Colorado River water, the primary source of water for 27 million people in California, already has an approximate salinity level of 700 mg per liter, 200 mg higher than the set standard deemed acceptable by the U.S. Environmental Protection Agency.
As the population of California continues to climb - by some estimates, Southern California alone is expected to reach a record 8 million people by 2020 - both the infrastructure and the salinity challenges will escalate.
Currently, as the result of the necessary importation of water into California, about 630,000 tons of salt annually accumulates in California aquifers, damaging the state's water infrastructure in the range of $95 million per year. Dealing with the water waste and the disposal of the concentrated pollutants collected from the water also is an expensive challenge. The UCLA Water Technology Research Center will look at new ways to enhance water recovery, as well as methods to increase membrane efficiency and decrease membrane fouling. As just one example, it will explore how to create a membrane surface that is less prone to fouling and scaling.
UCLA's School of Engineering already has 16 Ph.D. students studying various aspects of new water production, including desalination via low-pressure reverse osmosis membranes. The WaTeR Center also plans to initiate research on the integration of renewable energy, energy recovery and solar energy to power desalination plants and to enhance the production of desalted water. For more information, visit http://www.desalination.ucla.edu/desalination/.