Process for Removing Concentrated Contaminants from Reverse Osmosis Waste Gets Testbed

Achievement date: 

A new testbed at the Silicon Valley Water Purification Center in San Jose, Calif., is evaluating a process for removing contaminants that become concentrated after the reverse-osmosis treatment of wastewater effluent. The testbed is a project of the National Science Foundation’s (NSF) Engineering Research Center (ERC) for Re-Inventing the Nation's Urban Water Infrastructure, or ReNUWIt, based at Stanford University.


The project promises to help a water-starved world capture more potable water from the treatment of wastewater. The ReNUWit process deals with a key barrier to water-reuse efforts—the lack of a cost-effective approach for treating the concentrate that results from removing unhealthy elements through reverse osmosis.


Utilities commonly clean wastewater to enable using it for irrigation and industry. Much less common is purifying water for drinking. Reverse osmosis is a favored approach used in the process of purifying drinking water from water that has been preliminarily cleaned and recycled from waste.

But reverse osmosis produces concentrated waste that has been expensive to treat before safely discharging to streams. ReNUWit partnered with the Santa Clara Valley Water District and the San Francisco Estuary Institute to develop a cost-effective approach for removing trace organic contaminants, nutrients, and metals from reverse-osmosis concentrate prior to its discharge to a sensitive part of the San Francisco Bay.