Microbial cell technology to better clean-up rural waste

In a bid to help under-developed countries clean polluted water more effectively, researchers at the Washington State University (WSU) have developed a unique method to use microbes buried in pond sediment to power waste cleanup in rural areas.

The first microbe-powered, self-sustaining wastewater treatment system could lead to an inexpensive and quick way to clean up waste from large farming operations and rural sewage treatment plants while reducing pollution.

"This is the first step towards sustainable wastewater treatment," said Timothy Ewing from the WSU's Voiland college of engineering and architecture.

Microbial fuel cells use biological reactions from microbes in water to create electricity.

In the new method, the microbial fuel does the work of the aerator, using only the power of microbes in the sewage lagoons to generate electricity.

The researchers created favourable conditions for growth of microbes that are able to naturally generate electrons as part of their metabolic processes.

"The microbes were able to successfully power aerators in the lab for more than a year," added professor Haluk Beyenal.

Traditionally, waste from dairy farms in rural areas is placed in a series of ponds to be eaten by bacteria, generating carbon dioxide and methane pollution, until the waste is safely treated.

In urban areas with larger infrastructure, electrically powered aerators mix water in the ponds, allowing for the waste to be cleaned faster and with fewer harmful emissions.

The researchers believe that the microbial fuel cell technology is on the cusp of providing useful power solutions for rural communities.

They are now hoping to test a full-scale pilot for eventual commercialisation.