Lithium Australia NL’s (ASX:LIT) 90%-owned subsidiary Envirostream Australia Pty Ltd has started a field trial as it assesses the use of zinc and manganese derived from recycled alkaline batteries as micronutrients in blended fertilisers.
The fertiliser/wheat-seeding trial is underway near Kojonup, about 260 kilometres southeast of Perth, WA.
Envirostream hopes the use of nutrients in slow-release form – believed to be a first for the Antipodes – in the sandy soils, low in zinc and manganese that characterise WA’s wheatbelt region will provide growers with significant benefits.
“Recycled batteries to enhance fertilisers”
Lithium Australia managing director Adrian Griffin said: "Using recycled batteries to enhance fertilisers has the potential to divert toxic materials from landfill, provide the fertiliser industry with more sustainable inputs and improve crop yields.
“The slow-release nature of the micronutrients produced by Envirostream could prove a real advantage in terms of local crop conditions.
“We look forward to the outcome of the trials later this year."
Micronutrient/fertiliser agglomeration
The zinc and manganese micronutrients used in the blended fertilisers were recovered by Envirostream from single-use, disposable alkaline batteries (the type commonly found in torches, toys and remote-control units) in the form of mixed metal dust (MMD) at its recycling facility in Victoria, Australia.
For the field trials, the MMD was agglomerated with mono-ammonium phosphate (MAP) fertiliser.
The packaged fertiliser variants of MMD agglomerated with MAP fertiliser.
Field seeding trials
There were five types of furrow treatment in the controlled Kojonup seeding on June 5:
- No fertiliser in seed furrows;
- Application of MAP only to furrows;
- Addition of commercial fertiliser with added zinc and manganese to furrows, and
- Use of MAP agglomerated with two different dosages of Envirostream’s MMD.
Harvesting at the trial site is planned for December 2020, with results to follow in the first quarter of 2021.
Blended fertiliser development
In addition to conducting micronutrient field trials, the company is exploring the use of the alkaline MMD as a source of micronutrients with a number of fertiliser manufacturers.
Discussions regarding the commercial use of Envirostream Australia’s micronutrient blends are ongoing.