More practical way to recycle human urine as dry fertiliser is on the way.
The most nutrient-rich part of wastewater is human urine, which makes up less than 1% of the total volume but contains 80% of the nitrogen and 50% of the phosphorus. And many countries have used urines to fertilize small organic gardens at home in the U.S. and Europe. But urine recycling may never become a part of large-scale farming in industrialized countries, because the main problem is in transporting the liquid waste.
For example: farmers would have to spread 15,000kg of it just to fertilize a hectare of land. If there was a way to remove the water and extract just the nutrients, farmers would only need to apply 400kg of it for the same effect.
And three scientists: Prithvi Simha, Björn Vinnerås, Jenna Seneca from the Swedish University of Agricultural Sciences know how to do it and how to recycle the urine into valuable and sustainable farmland fertilisers differently than others, solid fertiliser with lighter in weight.
The three scientists have been doing research on turning human urine into dry, hygienic, and high-quality solid fertiliser. Phritvi Simha in his study “Alkaline dehydration of source-separated fresh human urine: Preliminary insights into using different dehydration temperature and media” stated that:…”For sanitation systems aiming at recycling nutrients, separately collecting urine at source is desirable as urine contains most of the nutrients in wastewater. However, reducing the volume of the collected urine and recovering majority of its nutrients is necessary, as this improves the transportability and the end-application of urine-based fertilisers. In this study, we present an innovative method, alkaline dehydration, for treating fresh human urine into a nutrient-rich dry solid.”
Below are the graphic abstract of the three scientists:…
He continued, “Our aim was to investigate whether fresh urine (pH < 7) added to five different alkaline media (pH > 11) could be dehydrated at elevated temperatures (50 and 60 °C) with minimal loss of urea, urine’s principal nitrogen compound. We found that it was possible to concentrate urine 48 times, yielding dry end-products with high fertiliser value: approximately, 10% N, 1% P, and 4% K.”
As reported in The Guardian this year: “Humans have been collecting urine and using it for fertiliser for a long, long time, but then in the west that really stopped with the invention of sewage system,” said said Dr Krista Wigginton, a co-author of the research from the University of Michigan. “We are just trying now to figure out with this infrastructure system that we have, how do we pull back and think differently about what goes into this sewage system and capture some of those valuable products before (they)get mixed and diluted with everything else?.”
Not only urine, but other natural human waste also has power for our future. The poo. The Nanyang Technology University (NTU) in Singapore has found a way to harness poo power and turned it into electricity, energy, bio-gas, and fertiliser by using No-Mix Vacuum Toilet system.The system has two chambers which separate liquid and solid wastes. As a country with mo natural resources, the natural human waste can be a good potential natural resources. Click here to find out more.
For more information about Swedish University of Agricultural Sciences: Website www.slu.se – Blog blogg.slu.se – SLU – Twitter @_SLU – LinkedIn SLU – Swedish University of Agricultural Sciences. – Instagram @studysustainability.
Source: We found a way to turn urine into solid fertiliser – it could make farming more sustainable — SCIENTISTS WANT TO USE YOUR PEE TO SAVE THE ENVIRONMENT —– Urine: the ultimate ‘organic’ fertiliser? — Alkaline dehydration of source-separated fresh human urine: Preliminary insights into using different dehydration temperature and media — SUSTAINABILITY Gee Whiz: Human Urine Is Shown to Be an Effective Agricultural Fertilizer — Urine: the ultimate ‘organic’ fertiliser?.