Scientists Just Found An Incredible Way To Use Leftover Coffee Grounds And Our Minds Are Blown
Coffee has found its purpose beyond kitchen shelves. Humans are replacing trees and greenery with concrete. The sight of any bare piece of land urges big MNCs or wealthy businessmen to make something out of it– a mall, office buildings, or even a parking lot. Most of these establishments are built on a foundation of concrete bricks, and new research has found a smarter recipe to produce concrete 30 percent stronger with this kitchen ingredient, as per a study published in the Journal of Cleaner Production.
The research revealed that adding charred coffee grounds to the concrete mix can significantly increase its strength as a building material. Australian engineers identified this technique as a sustainable alternative that could potentially reuse the 10 billion kilograms (22 billion pounds) of coffee waste, 75 million from Australia alone, generated globally in the form of used-up grounds, per a report by RMIT University.
Lead author Dr. Rajeev Roychand from RMIT University in Melbourne explained that the team developed the technique by turning waste coffee grounds into biochar through a low-energy anaerobic process at 350 degrees Celsius. Besides the sustainable use of coffee waste, he also noted how this process would prevent the greenhouse emissions of methane and carbon dioxide from biodegradable waste. “The disposal of organic waste poses an environmental challenge as it emits large amounts of greenhouse gases including methane and carbon dioxide, which contribute to climate change,” Roychand said. He is a Postdoctoral Research Fellow at the university.
While some people have repurposed waste coffee grounds by incorporating it into their gardens for plant growth, most of it ends up in landfills across the world. The lead author revealed that he and his team were determined to find an innovative way to utilize the vast amounts of coffee grounds in construction “to give coffee a ‘double shot’ at life.” However, coffee grounds and other organic products leak chemicals that weaken concrete’s strength and thus, cannot be added directly to the building material. This research further yields the potential of transforming organic waste into sturdy material through a process called pyrolysis.
It generally involves heating organic waste in the absence of oxygen leaving behind pyrolyzed forms of it that may be used in upcoming infrastructure projects. Roychand and his team also tried heating the pyrolyzed coffee grounds at 500 degrees Celsius in contrast to the typical 350 degrees. They found that the resultant biochar was not as strong as before. The study has gained interest among councils struggling with organic waste management and hopes to benefit from the innovative technique in the future. The construction industry is trying to match the pace of global urbanization. Therefore, industries are facing an ever-increasing demand for resource-intensive concrete that further impacts the natural environment.
RMIT engineer Jie Li pointed out that huge amounts of natural sand are extracted from river sediment on the banks and seabed. To cater to the demands of the construction industry, builders are caving out river basins to acquire heaps of sand that affect the river flow. "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,” she said. Hence, the engineer suggested a “circular economy approach” that would sway organic waste from landfills while preserving natural resources.