Brewing stronger foundations: Coffee waste revolutionizes concrete
Scientists have taken a closer look at the most underestimated waste, which is produced daily in tonnes worldwide. Their research has shown, among other things, that coffee grounds not only strengthen plants but also... concrete.
Coffee grounds seem to be the most underestimated waste. Plant enthusiasts have been fertilizing flowers, shrubs, and vegetables in the garden with them for years. Their rich nutrients, such as nitrogen, phosphorus, and potassium, have long been noted, and in smaller amounts, they also provide magnesium, calcium, iron, and zinc, which are beneficial for plant growth. Forums have also featured recipes for body scrubs. They were also sprinkled on sidewalks in the winter. Scientists have now found another use for coffee waste.
Coffee grounds bond well with cement and improve concrete structure
Australian scientists have discovered that the potential of coffee grounds is enormous, particularly in the context of construction. They proved that coffee waste can be processed in a way that significantly increases the strength of concrete by 30 per cent. This is indicated by research work from RMIT University in Melbourne, published in the scientific journal "Journal of Cleaner Production."
Strengthening concrete is based on the technology of processing coffee grounds through pyrolysis—an energy-efficient process that involves heating them to a temperature of 350 degrees Celsius without oxygen, which minimizes carbon dioxide emissions. Dr. Shannon Kilmartin-Lynch from the RMIT team, cited by "The Guardian," notes that such actions can also reduce coffee waste in capsule form.
Scientists are looking for more uses for coffee grounds
When transformed into biochar (a substance similar to charcoal), coffee grounds can partially replace sand used in concrete. Scientists also emphasize that the pyrolysis process used in this method is energy efficient. The researchers also reported that the grounds become a porous material as a result of such reutilization, which promotes bonding with cement, thus improving the concrete structure.
Although technologies using coffee waste in construction are in the early stages, scientists plan further tests and are already collaborating with local authorities on the practical application of this method in infrastructure, such as building sidewalks. Transforming coffee grounds into construction material not only reduces waste in landfills but also suggests the potential production of 24,800 tonnes of eco-friendly concrete annually if all coffee grounds in Australia were processed.
