‘Hungry’ bacteria extract energy from sewage
Researchers at UGent have developed a way to use bacteria to extract energy from wastewater, meaning future water purification process could be energy-neutral
In use in Washington, DC
Domestic sewage contains organic substances, mainly from toilets and kitchens. They are harmful to the environment but do contain energy. The researchers used bacteria to extract that energy from the organic substances. Before they deployed them, the researchers starved the bacteria for a period.
“The wastewater is then briefly brought into contact with the bacteria, which, because they’re hungry, gobble the organic matter without digesting it,” explained UGent professor Nico Boon. “This enables us to reap the undigested materials for energy recovery and high-quality materials.”
This so-called contact-stabilisation process means that up to 55% of organic material could be recovered from sewage, while existing processes recover a maximum of 30%. The researchers estimate that this amount can provide sufficient energy to completely purify sewage without the need for external electricity.
“This is an important step in developing a water purification process that is energy neutral or even produces energy,” said UGent professor Siegfried Vlaeminck.
The method has already been tested in practice. The DC Water agency, which is responsible for water purification in the US capital Washington, DC, is currently carrying out part of its water treatment process using the method developed in Ghent. That is because one of the responsible UGent researchers, Francis Meerburg, worked with DC Water for his PhD on the subject.
