Steps toward a low carbon future
CIMIC Group companies EIC Activities and CPB Contractors have taken a lead role in launching a report that provides a pathway to zero carbon cement.
Beyond Zero Emissions
The Rethinking Cement1 report, produced by climate solutions think tank Beyond Zero Emissions (BZE), sets out a pathway for modernising cement, eliminating carbon emissions, and building strong and durable infrastructure.
BZE is a nationally recognised and respected independent, not‐for‐profit climate change think‐tank providing peer reviewed research, detailed costings and guidance enabling Australian industries to transition to a low carbon economy. Rethinking Cement focuses on cement production, the single biggest industrial producer of emissions.
A zero carbon cement industry in a decade
BZE’s research proposes that Australia can enjoy a zero carbon cement industry in 10 years using already commercialised technologies, such as geopolymer cements, high‐blend cements and mineral carbonation. A key strategy is to replace 50% of existing cements with geopolymers as their manufacture produces fewer emissions – potentially zero.
Geopolymer cement can be produced from fly ash (a by‐product of coal‐fired power stations) and ground granulated blast furnace slag (a steel production waste product), with the report suggesting that Australia had 400 million tonnes of fly ash stockpiled from over a century of coal‐burning. Just a quarter of these stockpiles of fly ash could supply an estimated 20 years or more of domestic cement production.
CIMIC Group is proud to support BZE’s launch of the Rethinking Cement report which, we hope, will stimulate government and industry to shift to a zero carbon cement industry.
Geopolymer are already cost‐competitive and, in many cases, outperform traditional concrete in terms of:
• flexural strength – geopolymers have greater ability to be bent without cracking
• resistance to chlorides, acids and salts, making them a better option for uses such as sewer pipes and marine environments
• fire‐resistance, which suits applications such as road and rail tunnels
• shrinkage – geopolymers shrink less as they dry which can reduce unsightly cracking.
In Australia, a number of suppliers are currently offering geopolymer cements and they have been used on projects including retaining walls, precast footpaths, airport taxi‐ways, precast panels for buildings, sewer pipes, kerb‐sides, pavements and railway sleepers.