Surrey takes the p… in order to feed the world
22 Jul 2024
It sounds like the classic p… take but work is underway on a project to counter the world shortage of phosphorus by extracting it instead from human urine.
Researcher at the University of Surrey School of Chemistry and Chemical Engineering, Maano Tshimange says calculations suggest that mined sources of the mineral will largely expire within the next 50 years to a century.
Without a plentiful reserve, there will be a knock-on effect for the supply of fertiliser and growing challenges growing foodstuff.
In principle, the world’s burgeoning population provides a potential answer; phosphorus is the second most abundant mineral in the human body after calcium and substantial amounts are expelled through urination.
In fact, urine is regularly used as a fertiliser on a small scale by rural peasant farmers. However, only 3% of the content is phosphorus, with the rest comprised of water, making it unfeasible for mass transportation in this form.
Instead, the Surrey team aims to extract the phosphorus using a filter membrane to separate the two elements by osmosis and investigating how to prevent fouling or clogging of the technology.
Their pilot scheme which will run for a year, involves collecting 15 litres of urine from student volunteers using the university’s Guildford campus toilets. If successful and also scalable, the method could supply nearly a tenth of global needs, suggested Tshimange.
“Getting phosphorus from urine could be a simple, cheap alternative. And let’s face it, there’s so much of it available that we'll never be caught short. Human urine alone could provide as much as 11% of the world’s phosphorus needs,” said the researcher.
