Coffee Grounds Make Concrete 30% Stronger
Researchers in Australia have found that concrete can be made 30 percent stronger by replacing a percentage of sand with spent coffee grounds. Research is continuing at the RMIT University, but if the findings hold true it would be a win, win, win all the way around.
Almost all spent coffee grounds wind up in landfills as organic waste product, generated at the rate of 60 million tons a year. So besides creating value for a worthless waste, it will reduce the need for landfill space, and reduce the use of sand which is an increasingly expensive, dwindling natural resource —further contributing “to a greener circular economy approach to construction.” The construction industry uses 40 to 50 billion tons of sand and gravel each year.
Due to their fine particle size, researchers found that SCG (spent coffee grounds) that of all the concrete composites they tested, the one that replaced 15 percent of sand with SCG pyrolyzed at 350 °C (662 °F) led to a significant improvement in its material properties, resulting in a 29.3 percent enhancement in compressive strength.