Reducing the carbon footprint of cement

Cement is vital for a country’s economic development, the basic ingredient required to build housing and infrastructure. Today, the world cement market represents more than 2 billion tonnes per year, and demand for cement continues to increase, driven by economic and demographic growth and by the increase in urbanization, especially in emerging markets.
 
However, cement manufacturing generates CO2 and the industry as a whole represents around 5% of global CO2 emissions.
•     Around 60% of these result from the transformation of limestone at high temperatures – ‘decarbonation’ – to produce clinker, the basic component of cement.
•     Approximately 40% are generated from the energy used in the burning process.

Up until now, there have been three main ways to reduce CO2 emissions associated with cement production:

Increasing energy efficiency by optimizing processes and modernizing factories.

Introducing new cement plants using the best available technology or upgrading old plants.

Substituting fossil fuels with other energy sources.

Alternative fuels such as biomass, tires and industrial waste can be used to replace fossil fuels in cement kilns. This allows not only a reduction in the consumption of fossil fuels but also the safe disposal of waste that would otherwise be incinerated or land filled.

Using additives in cement to develop a large range of products according to their application.

 Natural products such as pozzolan or industrial by-products such as fly ash (a by-product of coal-fired power stations) or slag (a by-product of the steel industry) can be used in the cement production process as cement additives. These decarbonated additives have hydraulic binding qualities and can be used to produce less carbon-intensive cements.
Project Aether opens up a new avenue towards reducing the intrinsic CO2 emissions associated with cement production.

Learn more about the project

Learn more about the cement manufacturing process