Feb 21, 2012

Arizona State Engineers to Develop Treatment Solutions for Small Communities

EPA and NSF grants will fund research on nitrates, other contaminants

EPA and NSF grants will fund research on nitrates, other contaminants

Some of most recent advances in technology, chemistry, physics and materials science will be applied to new methods for ensuring water safety being developed by Arizona State University (ASU) engineers.

In a project supported by a $500,000 grant from the U.S. Environmental Protection Agency (EPA), Paul Westerhoff will lead an exploration of ways to improve the effectiveness of water treatment systems in the nation's small communities. He also will head a project supported by the National Science Foundation (NSF) to optimize the use of new technology for reducing a prevalent contaminant in groundwater.

Westerhoff is the associate dean for research at ASU's Ira A. Fulton Schools of Engineering, and a professor at the university's School of Sustainable Engineering and the Built Environment. His research partner for both projects is Kiril Hristovski, an assistant professor at ASU's College of Technology and Innovation. For the EPA project, they will be joined by Aaron Dotson, an assistant engineering professor at the University of Alaska – Anchorage who earned his doctoral degree in engineering at ASU.

For the NSF project—supported by a grant of more than $295,000—the research team will seek advances in the use of photocatalysts to reduce the amount of nitrates in water supplies.

High concentrations of nitrates in water can pose significant risks, including causing life-threatening diseases, and lead to excessive growth of algae or plankton in aquatic ecosystems. Westerhoff and Hristovski will experiment with different types of photocatalysts to reduce nitrates. Photocatalysis involves the acceleration of chemical reactions using the power of light. In this case, the researchers are seeking to produce reactions at the nanometer scale that will convert nitrate to a nonthreatening form. The researchers plan to eventually develop an open-access website to provide the public the latest information on nitrate occurrence, health risks and proven strategies for water treatment.

The EPA project will focus on ways to improve monitoring, testing and treatment of water systems in communities with populations of roughly 50 to 500 residents. Such communities rarely have the resources to maintain timely, effective and thorough methods of ensuring their water meets basic safety standards, Westerhoff said.

The team plans to develop hybrid sorbents (materials designed to absorb liquids and gases) capable of simultaneously removing multiple contaminants. In addition, the researchers will develop monitoring and sensing networks to enable simplified automated operation and testing of water systems designed to optimize the groundwater sorbent treatment systems.

Local officials in the Tohono O'odham Native American Indian community in Arizona and in a remote area of Alaska are being asked to participate in the research by conducting onsite demonstration projects.

Systems that can work in those locations could be applied with success in the vast majority of small communities throughout the country, Westerhoff said.