Brought to you by
Dr Farshid Pahlevani
Senior Research Fellow, University of New South Wales; PhD (Materials Science and Engineering), University of New South Wales
By 2050, the world population is predicted to rise from 7.6 billion people today to 9.2 billion.
That’s why University of New South Wales Senior Research Fellow Dr Farshid Pahlevani believes that reliable, sustainable sources of agricultural phosphorus are essential to maintaining global food production in the face of this rapid population growth, as well as in responding to the effects of climate change and depleting natural rock phosphate deposits.
Due to its phosphorus poor soils, Australia is the world’s ﬁfth-largest importer of phosphorus for domestic food production and the agricultural export industry. Most of the phosphorus for agricultural fertiliser currently comes from rock phosphate mines, most of which are found in Morocco.
The mining of these limited reserves has polluted many of the world’s waterways and created global dependence on a single non-renewable resource.
Pahlevani is developing a world-ﬁrst, single-step recycling process that transforms steelmaking slag and coffee waste into a sustainable source of agricultural phosphorus.
Pahlevani is developing a world-ﬁrst, single-step recycling process that transforms steelmaking slag and coffee waste into a sustainable source of agricultural phosphorus, which could deliver globally signiﬁcant environmental and economic beneﬁts.
Phosphorus is an unwanted component of iron ore that is removed during the steelmaking process. The traditional process for producing phosphorus from steelmaking slag uses acid leaching, which produces waster, and is energy intensive.
Pahlevani’s process, however, uses discarded coffee grounds to recover the phosphorus in a single step, leaving no hazardous byproducts.
“We mix the slag and the coffee grounds, and ensure that the
ratio, temperature and time are correct to selectively remove
only the phosphorus from the phosphorus oxide in steelmaking slag,” Pahlevani says.
“The phosphorus is removed as a gas, which is passed through argon, then through water, to condense into a yellow phosphorus, which can be used as a source of phosphorus.”
“The idea is very creative in bringing together completely different waste streams to deliver a useful product. This is an excellent example of how using innovation can reduce waste and produce a valuable product.”