January 2013, Vol. 25, No.1
Purifying fracking wastewater
The U.S. National Science Foundation has funded research that may help solve one of the environmental and public health risks associated with hydraulic fracturing, commonly called “fracking.” University of Minnesota (Minneapolis) researchers are developing biotechnology that would purify fracking wastewater, according to a university news release.
During the fracking process, water, sand, and chemicals are forced deep into the Earth, creating fissures that allow natural gas or oil to escape and be recovered. The resulting wastewater contains chemicals used during the process, as well as chemicals present underground. Wastewater treatment methods, such as evaporation and filtration, are expensive and energy-intensive and only reduce chemicals to a concentrated form, the news release says.
The new treatment, however, uses naturally occurring bacteria embedded in porous silica materials to biodegrade contaminants. The technology, originally developed to remove agricultural pesticides from soil and water, is being customized to degrade fracking chemicals. The goal is to make the wastewater suitable for reuse in fracking other wells and to reduce the total amount of water used by the industry, the news release says.
The research project has earned a $600,000 grant from the National Science Foundation’s Partnerships for Innovation program. The program pairs researchers with companies to produce innovative technologies, the news release says. The research team includes lead Larry Wackett, Alptekin Aksan, Michael Sadowsky, and Robert Elde, dean of the university’s College of Biological Science, who will lead interaction between researchers and companies.
The team will work with Tundra Cos. (White Bear Lake, Minn.) on silica encapsulation technologies and Luca Technologies (Golden, Colo.) on using encapsulated microbes to recover natural gas from depleted coal beds, the news release says. The university is tasked with further developing a platform technology that could be used by these and other companies, the release says.
The team also has won a University of Minnesota Futures Grant to explore methods for mitigating the environmental effects of fracking.
Removing resources from wastewater
PARC (Palo Alto, Calif.) scientists received a grant to pursue technology that treats wastewater by separating suspended solids from water into two distinct resources. The California Energy Commission awarded the $1 million grant to demonstrate the new Hydrodynamic Separation (HDS) technology for wastewater treatment in California, according to a PARC news release.
The modular, scalable primary treatment technology separates particles from water without using physical filters and can be implemented in both large treatment facilities and portable applications, the news release says. It recovers solids that can be processed through an anaerobic digester to produce methane and generate electricity.
The process removes much of the organic solids in wastewater, so it can be further treated during a secondary biological process. By reducing organic content in wastewater, there is a lower demand for oxygen and aeration energy in secondary treatment, resulting in energy savings, the news release says.
“The ultimate goal of this project is to help plants become energy neutral,” said Stephen Hoover, PARC CEO, in the news release. “To be able to process millions of gallons of wastewater and provide two types of output — electricity and clean water — which can be repeated across many counties, states, and countries is quite a remarkable project.” The project will help facilities handle an increased flow during storms by providing backup capability that can scale to millions of gallons per day.
PARC plans to work with the Sunnyvale, Calif., municipal water resource recovery facility to demonstrate the HDS pilot system. CDM Smith (Cambridge, Mass.) will support PARC for this project by providing technical expertise in the field of wastewater and stormwater treatment design and engineering review duri