Coffee grounds

Macedon Ranges, Australia

Type of waste: agricultural

Australian roasters Single O determined that spent coffee grounds accounted for more than 20 per cent of its carbon emissions. It’s estimated Australian landfill is made up of 3 per cent spent coffee grounds. But innovations are helping to reduce the amount, from circular economy waste management to a construction industry development that may also improve the sustainability of concrete production. https://www.hospitalitymagazine.com.au/a-new-future-for-old-coffee/

Coffee concrete

RMIT University, in collaboration with the Macedon Ranges Shire Council in Australia, has developed a technique for reinforcing concrete using biochar obtained from coffee grounds. They heat these remains without oxygen at high temperatures to turn them into a special powder called biochar, which is then mixed into concrete. This biochar is then mixed with cement to make it stronger—up to 30% stronger than ordinary concrete. In addition to keeping this waste out of landfills, it reduces the use of sand, and in the future, even less cement could be used.