Researchers at Luleå University of Technology, in collaboration with RecoLab in Helsingborg, want to improve the possibilities of concentrating nutrients from our faeces – and reusing them in fertilizer.
The toilet, the shower and the dishwasher, everything ends up in the same drain and then in a treatment plant. There, it is purified in several stages before it is released back into nature and diluted in lakes and waterways.
A wasteful method, say the researchers.
– What we do now is to send the water from the household to a treatment plant where all the nutrients from the food are not taken care of, they are just cleaned away and discarded, says Stephanie Rusch Fehrmann, PhD student at Luleå University of Technology.
Sorts out the toilet waste
In Oceanhamnen in Helsingborg there is a unique residential area where the toilet has its own drain, and is not mixed with detergent residues and other waste, which goes directly to the recycling and research facility RecoLab.
By concentrating the toilet waste that ends up here, the researchers hope to be able to develop effective methods to take advantage of the nutrients that we have taken in through food, but which then ended up in our faeces.
– Wastewater is not waste. Waste is a human invention. It is actually a resource of water, nutrients and energy. So we have to be smart and see it as a resource and not as a waste we invented, says Stephanie Rusch Fehrmann.
Circular system
Substances such as phosphorus and potassium are important both for the human body and as plant nutrients in artificial fertilizers. The substances are found naturally in the soil but are also mined in mines to be used on farms where the soil is not sufficiently nutritious. The researchers want to reuse the nutrients from our faeces and have a circular system, instead of minerals from the faeces being lost.