Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Watts from wastewater: New device produces power while treating sewage

27.10.2004


A new technology is being developed that can turn raw sewage into raw power. The device, called a microbial fuel cell, not only treats wastewater, but also provides a clean energy source with the potential for enormous financial savings, according to scientists at Pennsylvania State University.



Although power output is still relatively low, they say the technology is improving rapidly and eventually could be used to run a small wastewater treatment plant, which would be especially attractive in developing countries. It also could be used to treat waste from animal farms, food processing plants and even manned space missions. The report appears in the Nov. 1 edition of Environmental Science & Technology, a peer-reviewed journal of the American Chemical Society, the world’s largest scientific society.

Similar in design to a hydrogen fuel cell, the microbial fuel cell captures electrons that are naturally released by bacteria as they digest organic matter and then it converts the electrons into electrical current. “We generated up to 72 watts per square meter, which is 2.8 times that generated in a larger device reported earlier this year in ES&T,” says Bruce Logan, Ph.D., an environmental engineer at Pennsylvania State University and co-author of the paper. . While still a relatively small amount of power, the researchers have used these types of devices to run a small fan.


The technology is developing rapidly. Since submitting the current paper, Logan and his colleagues have tweaked microbial fuel cell devices to produce up to 350 watts per square meter. “Two years ago we had 0.1 . . . and now we’re in the 100s,” he says. “We’d like to get in the range of 500-1000. We’re looking for another order of magnitude increase.” Logan doesn’t envision using his microbial fuel cell for the same type of applications as hydrogen fuel cells, such as in automobiles or houses. “We see using this any place where there’s a high concentration of organic matter,” he says.

The most obvious application would be in wastewater treatment plants, which essentially could power themselves as they treat water. Such a technology would be particularly useful in developing countries, Logan suggests, because it would produce a net amount of electricity, offering a reason to keep a treatment plant running besides just treating wastewater. “Even if it’s only powering a cell phone tower, that would be a reason enough to keep it going,” he says.

David Bagley, a scientist at the University of Toronto, has calculated that the energy potential in wastewater is almost 10 times the cost to treat it. “If we could achieve just one-twentieth of that power, we could break even,” Logan says. “We’re confident we’re going to be able to do more than that.” “In our system, the two electrodes are separated by a proton exchange membrane (PEM), just like in a conventional hydrogen fuel cell,” says Logan. “It opens the door to using existing hydrogen-gas based stack technologies with bacteria in water.”

At the moment, scientists can’t exactly pull a hydrogen fuel cell off the shelf and use it to treat wastewater, but the design principles are very similar. Wastewater flows on one side of the cell and air flows on the other, continuously generating electricity while also removing organic matter from the water. The device also could be used to treat waste from the food processing industry and farms — especially hog farms, which have tremendous problems with costs and odors, Logan says. NASA scientists are even developing a similar technology to be used in manned space missions, turning the astronauts’ waste into extra power. Logan plans to build a larger version of his microbial fuel cell for demonstrations; he hopes to have the design completed in about six months.

The American Chemical Society is a nonprofit organization, chartered by the U.S. Congress, with a multidisciplinary membership of more than 159,000 chemists and chemical engineers. It publishes numerous scientific journals and databases, convenes major research conferences and provides educational, science policy and career programs in chemistry. Its main offices are in Washington, D.C., and Columbus, Ohio.

Michael Bernstein | EurekAlert!
Further information:
http://www.acs.org

More articles from Power and Electrical Engineering:

nachricht IHP presents the fastest silicon-based transistor in the world
05.12.2016 | IHP - Leibniz-Institut für innovative Mikroelektronik

nachricht High-precision magnetic field sensing
05.12.2016 | ETH Zurich

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

IHP presents the fastest silicon-based transistor in the world

05.12.2016 | Power and Electrical Engineering

InLight study: insights into chemical processes using light

05.12.2016 | Materials Sciences

High-precision magnetic field sensing

05.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>