RMIT and Victorian Council Trial World-First Coffee Concrete

RMIT University has teamed up with Macedon Ranges Shire Council to conduct a world-first coffee concrete footpath trial. The RMIT team has partnered with Australian-owned BildGroup, a civil infrastructure, asphalt paving and road profiling company, to deliver these circular-economy projects.

GALLERY  

Organic waste going to landfill, including spent coffee grounds, contributes 3 percent of greenhouse gas emissions, but Dr Rajeev Roychand and his colleagues at RMIT are set on transforming this waste into a valuable resource for the construction industry.

Organic waste cannot be added directly to concrete because it would decompose over time and weaken the building material. To overcome this challenge, the team has developed a technique to make concrete 30 percent stronger by using coffee biochar made with a low-energy process without oxygen at 350°C, to give the drink-additive a “double shot” at life and reduce waste going to landfill.

They use a similar technique to turn other organic waste, including wood chips, into biochar that can also be used to make stronger concrete.

Australia generates 75 million kilograms of ground coffee waste every year – most of it goes to landfills, but it could replace up to 655 million kilograms of sand in concrete because it is a denser material. Globally, 10 billion kilograms of spent coffee is generated annually, which could replace up to 90 billion kilograms of sand in concrete.

“It’s very exciting to see this world-first trial of our coffee and wood-based biochar in collaboration with Macedon Ranges Shire Council,” RMIT School of Engineering’s Dr Rajeev Roychand says.

“Sand is getting scarce over time, and this waste can replace up to 15 percent of the sand in concrete.”

The researchers will evaluate the performance of the concrete in these trial footpaths in Gisborne, Victoria, with the aim of supporting the further roll out of this innovation.

“We are currently working in the supply chain sector so that we can make this research into a mainstream product for commercial applications, and we’re not only looking into coffee ­– we’re expanding this into all forms of different organic waste,” Dr Rajeev explains.

“Every biochar produced from a different organic material comes with varying composition, in addition to the difference in carbon content, particle size and absorbency, that can boost the performance of concrete in a range of ways.”

The trial with Macedon Ranges Shire Council did not reduce the amount of cement normally used to make concrete for footpath projects, but the RMIT team plans to experiment with using less cement.

Solar Victoria continues to enforce industry standards for consumers purchasing energy-efficient hot water systems under its flagship Solar ...

In the rapidly growing Nanshan District of Shenzhen, China, architecture studio Büro Ole Scheeren has revealed its latest ...

A natural alternative for lining internal walls and ceilings, Durra Panel is a truly sustainable building material made ...

RMIT University has teamed up with Macedon Ranges Shire Council to conduct a world-first coffee concrete footpath trial. ...

Fibre-reinforced polymer (FRP) composite bars have emerged as a potential game-changer for construction, particularly in concrete structures built ...