Reducing cement’s carbon footprint requires more than switching to cleaner energy. Lower-clinker cement formulations, alternative materials, more efficient production, cleaner fuels and carbon capture can all play a role in reducing emissions.
In Part 2 of The Carbon Challenge in Cement, EXPLAINED by Lion explores the technologies and materials that could reshape how cement is produced.
Reducing the amount of clinker
A major opportunity lies inside the cement itself.
Conventional cement depends heavily on clinker, which is responsible for a large share of its carbon footprint. By replacing part of the clinker with other suitable materials, the carbon intensity of cement can be reduced.
These materials can include:
- Fly ash
- Slag
- Natural pozzolans
- Calcined clay
- Finely ground limestone
Materials such as limestone added directly to cement do not go through the same clinker-making process, while calcined clay can be produced at lower temperatures than conventional clinker.
Cleaner and more efficient cement production
The production process itself can also change.
More efficient kilns can reduce energy demand, while alternative fuels, renewable electricity, electrification and potentially hydrogen can help reduce emissions associated with producing the extreme heat required for cement manufacturing.
But cleaner energy cannot eliminate all cement emissions.
Why is carbon capture important?
During clinker production, limestone releases CO₂ through the chemical process of calcination.
These process emissions remain even when the energy used by the plant becomes cleaner.
Carbon capture can separate CO₂ from the exhaust before it reaches the atmosphere. The captured carbon can then be compressed, transported and stored.
However, carbon capture also requires significant equipment, energy, transport infrastructure and secure storage.
There is no single solution
Reducing cement emissions requires a combination of approaches:
Lower clinker content. Cleaner energy. More efficient plants. Alternative materials and fuels. New cement chemistries. Carbon capture.
Each tackles a different part of the challenge.
Together, these technologies can help the cement industry continue supplying an essential construction material while significantly reducing its carbon footprint.
Cement is not going away. But the way we produce it is changing.
And the story continues. In Part 3, EXPLAINED by Lion takes a closer look at Supplementary Cementitious Materials (SCMs), where they come from and why sourcing, processing, storing and transporting them is becoming increasingly important.
Watch The Carbon Challenge in Cement (Part 2)
Discover the technologies, materials and innovations shaping the transition towards lower-carbon cement.
