New research points at “hungry” bacteria able to double the energy from sewage
Researchers from Ghent University have discovered a pre-treatment of bacteria that doubles the energy outcome.
Domestic sewage is harmful to the environment but it contains energy. Researchers from Ghent University discovered how to efficiently extract this energy from wastewater.
“The levels of organic matter in sewage are too low to be directly recovered. We investigated how we can use bacteria to capture this material. Our approach is unique because we have developed a high-rate variation of the so-called contact-stabilisation process.” Said Francis Meerburg, the researcher from Centre for Microbial Ecology and Technology.
Professor Nico Boon said: ‘We periodically starve the bacteria, in a kind of ‘fasting regimen’. Afterwards, wastewater is briefly brought into contact with the starved bacteria which are gluttonous and gobble up the organic matter without ingesting all of it. This enables us to harvest the undigested materials for the production of energy and high-quality products. We starve the rest of the bacteria, so that they can purify fresh sewage again.’
By existing processes only 20-30% of the organic matter is recovered from sewage and this number can reach up to 55% is the contact-stabilisation process is used, which would be the sufficient amount for energy production to completely treat sewage without the need for external electricity.
Ghent University said in a statement: ‘Going from a lab development in Belgium directly to large-scale application abroad is not an ordinary event. The interest from the industry clearly shows that it is time for more affordable and sustainable processes in wastewater treatment.’
Source: Bioenergy Insight
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