LeadIT and GCCA’s Green Cement Technology Tracker expanded to monitor calcined clay kilns

Concrete and cement are the world’s most used building materials. They are vital to the built environment for homes, offices and infrastructure, but currently account for around 7% of global CO2 emissions. With the launch of the GCCA’s Concrete Future 2050 Net Zero Roadmap the sector became the first heavy industry to set out a clear commitment and plan on how to decarbonize.

Tracking progress towards net zero is an essential part of the Roadmap. The Green Cement Technology Tracker, was launched last year by the Global Cement and Concrete Association (GCCA) and the Leadership Group for Industry Transition (LeadIT). The tracker monitors the global use of technologies that will help the industry decarbonise and will provide transparency and useful data to the industry, policymakers, academics and the public.

When the tracker was launched it initially monitored the development of carbon capture projects and now it has been expanded to include the use of clay calcination kilns.

Calcined clay, also known as metakaolin, can be used in the making of cement and can help to make significant CO2 reductions, due to the lower amount of energy the manufacturing process needs.

Per Andersson, Head of the Secretariat – LeadIT said: “Transparency is key. In order to empower the industry and policymakers committed to emission reductions, our goal is to provide comprehensive tracking of investments in low-carbon cement production. This new addition to our trackers is extending the scope and quality.”

The GCCA’s Cement, Innovation and ESG Director, Claude Loréa, said: “Driving down emissions requires investment in new technologies and production methods and incorporating calcined clay can contribute significantly making it a valuable strategy for sustainable construction.”

The GCCA’s Roadmap estimates that by using calcined clays in the production of cement, instead of limestone, it is possible to reduce emissions in the production process by 11%.

Karen Scrivener, Professor at Ecole Polytechnique Fédérale de Lausanne (EPFL) in Switzerland is an expert on the use of calcined clays and was recently appointed to the United Nations SDG group. She said “Ultimately, we’re constrained by the materials we have on earth. There’s no overnight replacement to cement. However the development of calcined clays, which are widely available, offers the world an exciting opportunity to reduce CO2 emissions in cement production.”

Expansion of the tracker’s scope now means it is monitoring development of two of the newest technologies which are helping to decarbonise cement plants – CCUS and calcined clays.

For media inquiries, please contact:

Eileen Torres Morales, Analyst and Transition Tracker Lead, LeadIT, [email protected]

Jane Birch, Communications Lead, LeadIT, [email protected], +46 722 14 96 16

Simon Thomson, Head of Media, GCCA, [email protected]

What are the sources of CO2 emissions in the cement and concrete sector?

During the production of cement clinker which is the main component of cement, limestone is heated in a kiln at high temperatures typically around 1450°C in a process known as calcination which releases CO2 as a byproduct. Cement is needed for the production of concrete. Additionally the energy intensive nature of cement production requires fuel, typically fossil fuels, to heat the kilns and this contributes to CO2 emissions.

What is calcined clay?

Calcined clay, also known as metakaolin, is produced by heating sources of kaolin clay (such as paper sludge) to temperatures between 650°C and 750°C. The resulting material can be added to cement as a substitute for clinker.

How does calcined clay contribute to emissions reduction?

The use of calcined clay reduces the need for clinker production which is an energy intensive process. Clinker production requires much higher kiln temperatures for calcined clay. By substituting clinker with calcined clay less energy is required leading to lower emissions. Calcined clay also releases fewer greenhouse gases when compared to the calcination of limestone.