RMIT scientists win national award for “coffee concrete”

A group of researchers from RMIT University have taken out the people’s choice Problem Solver Award at Universities Australia’s Shaping Australia Awards after inventing method to turn coffee grounds into concrete.

Australia drinks a lot of coffee. Nationwide, 75 million kilograms of ground coffee waste is generated annually, putting 6.87 million tonnes of organic waste in landfill. Three per cent of all Australia’s greenhouse gas emissions can be blamed on these dumps.

Researchers from RMIT University – Dr Rajeev Roychand, Professor Jie Li, Associate Professor Shannon Kilmartin-Lynch, Dr Mohammad Saberian, Professor Guomin Zhang and Professor Chun Qing Li – looked at this waste and saw opportunity, transforming coffee waste into a material used to create concrete that is 30 per cent stronger than the old stuff.

These scientists have found a way to lessen waste going into landfill by giving it a new life as a construction material, all while reducing demand on the increasingly scarce resource of sand- a major component in concrete.

Lead researcher Doctor Rajeev Roychand told Inner City News that this worked by heating the coffee grounds at high temperatures without oxygen being present. This produces a biochar – a porous carbon rich material that can replace the sand component of concrete.

If this process is adopted widely in the construction industry, from the 75 million kilograms of ground coffee waste we produce every year, 655 million kilograms of sand could be saved.

For its achievement, the research team won the public vote in the category of “problem solver”, bringing an award from the Shaping Australia Awards, held in Canberra, back to Melbourne. For the Dr Roycahnd it was “quite amazing”, but also unexpected.

“We didn't expect this, it was just like any other research paper for us. But something about it clicked in people's mind,” Dr Roycahnd said.

RMIT Researchers Dr Rajeev Roychand (left) and Professor Jie Li (right) with RMIT Vice-Chancellor Professor Alec Cameron celebrating their national research award at Parliament House in Canberra.

Sustainability was a large aspect of this project, flowing all the way down to the sourcing of the coffee grounds used in the initial research stage. Coffee grounds were provided by Talwali Coffee Roasters, who were “thrilled” to be involved in the project.  

“As an Indigenous-owned business, Talwali Coffee Roasters is deeply committed to sustainable practices that honour our connection to the land,” director of partnerships for Talwali Dean Paten said.

“This innovative research has created a potential for diverting organic waste from landfills to high-value construction applications, contributing to environmental sustainability, reducing greenhouse gas emissions, and paving the way for a more circular economy in Australia's construction industry.”

Dr Roycahnd said that using organic waste also had the added benefit of creating a low carbon circular economy where greenhouse gas emissions were kept to a minimum.

“There’s no point disposing of materials when all the results are negative. When you’re spending money and causing ecological harm,” he said, adding “if we can reuse it, why not?”.

The coffee concrete has already been tested out. RMIT teamed up with Macedon Ranges Shire last year in a world first trial, making a footpath out of the coffee concrete, with positive results.

So positive in fact, that coffee concrete went on to make its debut in a major infrastructure project, used in the Pakenham Rd upgrade as part of Victoria’s Big Build Project.

So, what’s next for this innovation, and the research team who helped make it a reality?

For coffee concrete, commercialisation is the next step. There has been plenty of interest, globally and internationally, with RMIT University close to finalising an exclusive agreement with a commercial partner. Operation is expected to begin in the next few months.

“We have got a big investor that is setting up the whole process. They have already looked at the supply chain, from sourcing to production to end users. That process is going on behind the scenes and our team is assisting them on the technical side”, Dr Roychand said.

For the team, they are currently researching ways to give other forms of organic waste a second life, with results, while not published yet, being “quite positive”.

This award-winning research was published in the Journal of Cleaner Production and can be found here.