Boral-led team investigates calcined clay in lower-carbon concrete

Building materials company Boral is developing a lower-carbon concrete product using calcined clay as an alternative supplementary cementitious material (SCM.)

The has announced that it is leading a two-year SmartCrete CRC-backed project, also involving the University of Technology Sydney (UTS), Transport for NSW, and industrial process specialist Calix, aimed at “further demonstrate the technical feasibility of calcined clay concrete for use in Australian buildings and infrastructure”.

Boral said the project aims to ensure supply of its lower-carbon concrete products, with the SCMs blast furnace slag and fly ash tipped to decline. These are byproducts from steel making and coal plants, respectively, and are used by the industry to partially substitute for cement.

The first clay batch has been successfully processed using Calix’s calcination technology, according to a statement from Boral on Thursday.

“The industry is constantly looking for ways to innovate, push the boundaries and find ways to be more sustainable. Given the abundance of clay in Australia, using Australian calcined clay was a natural decision for us,” said Dr Ali Nezhad, Head of Sustainability and Innovation at Boral. 

“We have been impressed with the work done to date and initial testing in this project is promising. We look forward to the building and construction industry in Australia embracing these new innovations.”

The project follows three years of work at UTS’s Boral Centre for Sustainable Building on the suitability of local clay resources.

Calcined clay is being investigated around the world as a lower-carbon substitute for limestone-based cement, which is responsible for most of the carbon emissions in concrete. 

The concrete industry contributes roughly 8 per cent of all the world’s carbon dioxide emissions.

Picture: supplied

Further reading

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