It’s no secret that coffee grounds have many virtues. In cosmetology, we know their benefits for fat removal, against orange peel skin and against dark circles. On a daily basis, we also use them to neutralize bad odors from the refrigerator, the worktop or the toilet. And we also find them in the garden, as fertilizer or to scare away mosquitoes and other small critters.
But recently, Australian scientists have discovered a whole new use for it. And this one might surprise you… Researchers at RMIT University in Australia made a rather original discovery a few months ago. Coffee grounds could strengthen concrete by 30%. So? The number of organic waste sent to landfills would be reduced, as would the extraction of natural sand for the production of concrete.
Coffee to build our buildings of tomorrow
All over the world, humans are building tirelessly, forcing builders to extract ever more sand to make concrete. A real disaster for the environment. For the good of the planet, scientists have therefore tested a technique transforming coffee grounds into biochar. And the result is surprising: by replacing 15% of sand with coffee biochar, the resistance of concrete is improved by 30%. This discovery, which offers a circular approach for the construction industry, was published in the Journal of Cleaner Production in September 2023.
This miracle recipe is more than interesting when you know that Australia generates about 75,000 tonnes of ground coffee waste each year. In France, the population generates nearly 400,000 tonnes of coffee grounds per year. And in the world then? No less than 7 million tonnes every year. “The concrete industry has the potential to contribute significantly to the increase in the recycling of organic waste such as used coffee,” says Kilmartin-Lynch, from RMIT University.
A real step forward for the good of the planet
“Disposing of organic waste poses an environmental challenge because it emits large amounts of greenhouse gases, including methane and carbon dioxide, which contribute to climate change.”, explains Rajeev Roychand of RMIT University. With this solution, many tonnes of coffee grounds could be recycled, while reducing extraction and the massive use of sand. The goal for these researchers: “Taking care of the country and making sure there is a sustainable life cycle for all materials. But most importantly keeping things out of landfill to minimise the impact on the environment.”
For now, scientists are studying the strength of this new blend and its durability. And who knows, coffee could soon be found within our walls.
