Beyond Zero Emissions (BZE), a climate change think tank based in Fitzroy, Victoria, in Australia, has outlined a pathway that it says would deliver a zero-carbon cement industry in Australia. The plan forms a part of its Zero Carbon Australia series, which outlines a costs a transition plant to zero emissions within ten years.
The plan is based around five strategies. The first three deliver a zero-carbon cement industry and include switching to geopolymer cement for 50% of Australia’s supply, supplying the remaining 50% with high-blend cements, and employing mineral carbonation to capture the emissions for the remaining production of portland cement.
Geopolymer cements – made from flyash and ground granulated blastfurnace slags – are existing products that do not generate greenhouse gases during manufacture. “Therefore, zero-emission geopolymer cements are possible,” BZE said in its report.
The second two strategies take a longer-term perspective and would “enable us in the longer term to go beyond zero emissions by changing the way we build and turning our built environment into a carbon sink.”
According to BZE, by “designing structures to use concrete more efficiently, utilising high-strength cement, and replaying concrete with timber, overall cement consumption could be reduced by around 15% in 10 years.”
The is also potential to develop magnesium-based cements that absorb carbon dioxide and “would therefore have a negative emissions profile.”
In addition to outlining a technological pathway to zero-emission cement, BZE also called upon government and the Australian cement industry to support the shift to a zero carbon cement industry. This would include a national price on cement carbon emissions, including imported cement, backed up with a progressive national target to reduce the carbon intensity of cement.
Government and the construction industry procurement guidelines could also be adapted to prioritise the use of low-carbon cements and mandating their use for non-structural purposes. “Such changes to procurement would be facilitated by increasing the incentives to use low-carbon cements in sustainability rating tools,” BZE added.
Read the article online at: https://www.worldcement.com/asia-pacific-rim/23082017/think-tank-outlines-pathway-to-zero-carbon-cement/