Every year 6,600 tons (6,000 tonnes) of alkaline batteries are sold annually around Australia and the Battery Stewardship Council estimates that at the end of their useful life, 97% of these spent products are thrown away and end up in landfill sites where they leak into the soil, causing pollution.
Recycling battery elements as crop fertilizer.
Envirostream is an Australian company that produces a mixed metal dust (MMD) containing cobalt, nickel, lithium and carbon from a 3,300 ton (3,000 tonne) per annum lithium-ion battery recycling plant and ships it to a South Korean company – SungEel – for refining into chemicals that will be incorporated in new batteries.
In 2019 Envirostream began to assess the use of zinc and manganese, obtained from recycled alkaline batteries, as micro-nutrient supplements in fertilisers. It conducted an initial round of “glasshouse pot trials”, growing wheat in a variety of controlled scenarios including using the recycled zinc and manganese separately as fertiliser sulphates and a combination of the two metals as fertiliser grade sulphates. Testing was also conducted on growing the wheat using no fertiliser micro-nutrients.
From this, field trials are being carried out in near the rural town of Kojonup around 160 mi (260 km) from Perth in the wheat belt of Western Australia, a region that produces about 15.4 million tons (14 million tonnes) of grain annually and serves as a major contributor to Australia’s exports.
The Kojonup site was selected for its low pH, as well as accompanying zinc, manganese and phosphate deficiencies. Adding zinc would assist in making chlorophyll. In addition to Australian field trials, Envirostream, 74% owned by Lithium Australia, intends to conduct further trials overseas in jurisdictions outside Australia which means seeking out partners willing to explore.
Prior to this in 2018, in Kärsämäki, central Finland, a team led by Mikko Joensuu and Joni Rahunen created a cleantech company called Tracegrow to recycle batteries made in Finland and also use the zinc and manganese to enrich soils for growing food crops.
Batteries are first crushed, then filtration and purification processes remove toxic elements such as mercury and nickel. It is important that these do not end up in the fertiliser as they could make their way into the food we eat so testing of the final product is rigorous. Once removed, they are sent on to be safely disposed of by hazardous waste treatment plants.
Initially, Tracegrow’s ZM-Grow fertiliser was used on tomatoes, cotton and avocados with promising results. On March 30th 2020 Tracegrow was granted an international patent and signed up a distribution partnership for Australia and New Zealand with ReNutrients PTY Ltd.
What you can do: Dispose of your used bateries, single use or recyclable, with care, as they may well bear fruit.
Discover Solution 90: cross-laminated timber
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