Using spent coffee grounds for making concrete can greatly boost circularity – GWC Mag

“The ongoing extraction of natural sand around the world – typically taken from river beds and banks – to meet the rapidly growing demands of the construction industry has a big impact on the environment,” notes Professor Jie Li, who led the research.

“There are critical and long-lasting challenges in maintaining a sustainable supply of sand due to the finite nature of resources and the environmental impacts of sand mining,” Li adds. “With a circular-economy approach, we could keep organic waste out of landfill and also better preserve our natural resources like sand.”

Thus, replacing sand with biochar from spent coffee grounds could not only strengthen concrete but also help the environment and reduce waste at the same time. Each year 10 billion kilograms of coffee grounds are generated. Australia alone produces 75 million kilograms of that. Most of this organic waste ends up in landfills.

The research is still in its early stages, “but these exciting findings offer an innovative way to greatly reduce the amount of organic waste that goes to landfill,” stresses Shannon Kilmartin-Lynch, a postdoctoral research fellow at RMIT University in Melbourne.