September 2012, Vol. 24, No.9

Research Notes

Database provides tool for aging infrastructure challenges

Utilities face many challenges from aging and deteriorating wastewater and water infrastructure. But now there is a new tool to help address these challenges and share lessons learned by utilities.

WATERiD, the WATER infrastructure Database, enables utilities to share their experiences and information on managing water infrastructure, according to a Water Environment Research Foundation (WERF; Alexandria, Va.) news release. Utilities can submit information on cost performance and capabilities of various technologies to learn which practice or technology is right for their application, the news release says.

WERF, which provided funding under a cooperative agreement with the U.S. Environmental Protection Agency, launched the database last year. Sunil Sinha, associate professor of civil and environmental engineering at Virginia Polytechnic Institute and State University (Blacksburg), developed the website.

Access the website at www.waterid.org.


Reverse osmosis may not remove organic nitrogen from wastewater

Organic nitrogen removal is variable, and reverse osmosis may not consistently produce total nitrogen levels less than 1.0 mg/L, according to a new report by researchers from Brown and Caldwell (Walnut Creek, Calif.) and the City of Escondido, Calif. The July issue of Water Environment Research contains an article on this work.

The researchers conducted a pilot study to determine total nitrogen removal by reverse-osmosis processes. They compared organic nitrogen removal rates with removals observed from three full-scale reverse-osmosis facilities and four pilot studies, the article says.

“The nature and concentration of organic nitrogen in secondary effluent will vary depending on the wastewater,” the article says. “Therefore, it is not possible to know the actual organic nitrogen concentration in reverse osmosis effluent without testing.”

Organic nitrogen in secondary effluent can have low molecular weights and exist as uncharged species that may not be removed through reverse osmosis. Its measurement at low levels may not be accurate using traditional methods, so alternative measurement methods may be needed, the article says.

Identifying organic nitrogen concentrations is crucial for municipalities attempting to achieve low total nitrogen levels and evaluating related processes, the article says. Using upstream biological nutrient removal to target inorganic nitrogen, coupled with a physical/chemical process, such as coagulation or activated carbon, to target organic nitrogen, could be a potential solution, the article says.

The article, “Analysis of Organic Nitrogen Removal in Municipal Wastewater by Reverse Osmosis,” appears in the July issue of Water Environment Research and can be downloaded free at http://goo.gl/cm7lY.

 

Water Environment Research allows open access to one article per issue on a range of important technical issues such as nutrient removal, stormwater, and biosolids recycling. 

 

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