Waste not want not

With more than a third of all waste in Australia generated by the construction and demolition sector, a new product out of Western Sydney University is set to tackle it.

Eight years have gone into the development of CO2 Concrete – the work of Professor Vivian Tam, Director of the Centre for Infrastructure Engineering and Associate (International) and Discipline Leader (Construction Management) at the School of Engineering, Design and Built Environment.

“With CO2 Concrete, we put crushed recycled concrete into a pressurised chamber and inject it with carbon dioxide which allows it to be as strong and durable as virgin concrete, while reducing carbon emissions from concrete production,” Prof Tam said.

Test slabs were poured at WSU’S Hawkesbury campus in 2019 and Blacktown Animal Rehoming Centre in 2022, so the product could be available for commercial use in the near future.

“We are currently engaging in high levels of discussion with concrete suppliers about commercialisation with the hope that CO2 Concrete will be able to sell in the market very soon,” said Professor Tam. “It has many benefits, with sustainability being a major one so it is exciting to have interest from those in the construction industry.”

Professor Tam also has plans to develop another recycled product called Het-Crete, with the use of environmentally friendly chemicals.

“CO2 Concrete is from clean concrete waste but Het-Crete is mixed aggregate from construction and demolition waste, which is more difficult to recycle,” she explained.

“This will be the world’s first build material for high grade construction so we are researching the processes we can use to speed up this new product development. This will expand the life cycle of the product to benefit the planet.”

The Australian Research Council (ARC) Future Fellowship is funding this research to the tune of $1.1 million over four years.

Image: Professor Vivian Tam. Source: WSU/Sally Tsoutas

About the author

Desi Corbett

Desi is our weekly news journalist and the editor of Concrete in Australia magazine for 10 years. She has been heavily involved in all forms of engineering since 2013; part of a 30-year writing career across a range of subjects and media.