Thousands of tonnes of electronic waste ends up in landfills each year, but now there’s a new way of recycling old technology – by using metal-hungry microbes.
“What we’re doing is using micro-organisms to extract the value, and that’s a world-first technology,” Mint Innovation CEO Will Barker said.
Circuit boards contain gold and copper, but many end up in rubbish dumps because no one can extract the metals, but that’s all been changed with Mint Innovation’s metal extracting lab.
“First step of the process is one of our partners in Wellington remark it – they collect these circuit boards, put them in a shredder, and it creates this fine powder,” Ollie Crush, Mint Innovation’s chief scientist, said.
The powder is dissolved into a solution, and then the secret weapon is unleashed – a microorganism that eats metals.
“They suck up these metals like gold, like a sponge, and in doing so, detoxifies that environment because they have a solid mass, and we put them in a liquid here. Then, we can separate the two in our process.”
Other extraction methods exist overseas, but they involve dangerous gases – even cyanide.
Mint Innovation’s invention is both low-cost and eco-friendly, but it’s still in the development stage.
It takes up to a week to extract small parts of a circuit board, and you’ll need 15kg of them to get about 3 grams of gold.
“We’re building a much larger scale plant in NZ next year and that will be more automated and more efficient so we can process larger volumes more quickly,” Mr Barker said.
The goal is to recycle all 3000 tonnes of old circuit boards we throw away each year.
It aims to create 600 tonnes of copper, which is 12 per cent of what we import, and 600kg of gold.