Using mining waste to fight climate change & produce sustainable food

7 JUN 2022 10:16 AM AEST

Using mining waste to fight climate change& produce sustainable food

Could a synthetic grain made from the by-products of mining helpin the fight against climate change, reduce river pollution and provide asustainable fertiliser for the agricultural industry?

Researchers from Griffith University’s Australian Rivers Instituteare about to find out with an $800K research program partnering with ZeotechLimited to develop the potential use of a synthetic zeolite grain to soak upexcess nutrients from waterways and redeploy it across fields as fertiliser,where it can simultaneously sequester carbon drawn from the atmosphere.

“The idea that we can take a waste stream like extraction residuesand turn them into a product that has the potential to help combat two majorenvironmental issues is extremely exciting,” said project lead Dr Chris Pratt,from the Australian Rivers Institute.

“This is a potential win-win technology for rural communities,opening up expanding carbon markets and at the same time trimming their outlayson fertiliser. This technology could put rural communities in the driver’s seatto lead the transition required to meet Australia’s commitment to net zeroemissions by 2050.”

In the last 50 years flows of nutrients like nitrogen andphosphorus into our rivers and waterways and carbon dioxide into our atmospherehave far surpassed levels considered safe for the planet.

Project lead Dr Chris Pratt from theAustralian Rivers Institute

While people are aware of climate change and the problemsassociated with excess carbon in the atmosphere, few have heard of the equallyserious problems caused by too much nutrients being washed into waterways.

“Humanities discovery of the Haber-Bosch process to pull nitrogenout of the atmosphere and turn it into fertiliser has inevitably led to massiveincreases in the flow of nutrients in agricultural ecosystems, with much of itending up in rivers, lakes and dams,” Dr Pratt said.

“In the water, nutrients do the same job as they do on land;stimulate plant growth. This leads to algal blooms in waterways which, whenthey die, decompose draining the oxygen out of the water causing fish kills anduninhabitable dead-zones.”

Preliminary results of Dr Pratt and team suggest that thesynthetic zeolite grains being studied have the ability to adsorb large amountsof nutrients and can be used to remove them from affected waterways, nullifyingthe potential problems they can create.

Synthetic zeolites are manufactured aluminium and silicateminerals with a sponge-like structure, made up of tiny pores that allows themto act like molecular sieves which can be designed to selectively absorbspecific target molecules.

“The relatively weak adsorption of the nutrients to thesesynthetic grains, combined with their ability to retain moisture and buffer pH,reducing potential soil acidification, make them a compelling fertiliserdelivery platform definitely worthy of further investigation,” Dr Pratt said.

“Our goal is to characterise these grains, assessing and improvingon their ability to capture nutrients and return them to agricultural soils, aswell as developing their ability to bind pollutants and carbon in soils theyare deposited in enhancing climate mitigation in agricultural landscapes.

“With regard to the latter, we’ll investigate their ability manageagricultural pollutants by locking up agricultural pollutants and pesticidesreducing their availability to organism in the soil and to sequester CO2 fromthe atmosphere with the potential for long-term soil carbon storage.”

This technology could represent a tangible opportunity to supportsustainable food production and simultaneously draw carbon out of theatmosphere in the fight against climate change.

“The hope is that it could all but removing the need for energyintensive fertilisers that end up in waterways, reducing farmers costs,providing an additional revenue stream through carbon farming and increasingtheir ability to cope with existing and emerging challenges like fertiliserresource scarcity and the increasingly difficult growing conditions associatedwith changing climates.

University Release. This material from the originatingorganization/author(s) may be of a point-in-time nature, edited for clarity,style and length. The views and opinions expressed are those of the author(s). https://news.griffith.edu.au/2022/06/07/using-mining-waste-to-fight-climate-change-produce-sustainable-food/?utm_source=miragenews&utm_medium=miragenews&utm_campaign=news

Tags: atmosphere, Australia, Australian, carbon dioxide, carbonfarming, carbon storage, climate change, Discovery, Griffith, GriffithUniversity, investigation, pollution, sustainable, technology, university,zero-emission