Up to 60 percent of CO2 emissions from cement and lime manufacturing are released directly and unavoidably from the processing of the raw materials – not from the combustion of fossil fuels. This occurs in both lime and cement manufacture via the following reaction:
CaCO3 (limestone) + heat -> CaO (lime) + CO2 (carbon dioxide)
Since 1990, the largest multinational cement companies have reduced their CO2 emissions by 20-25 percent. They have done so by improving energy efficiency and using waste-derived fuels and raw materials, as well as replacing the energy-intensive clinker by other constituents in cement or concrete.
But in order to reach the EU’s emissions reductions targets by 2050, carbon capture technologies need to be applied to the majority of cement plants, and Calix’s technology is uniquely placed to support the industry to achieve these targets in a timely, effective and efficient manner.
Calix is leading a consortium of some of the world’s largest cement and lime companies with the goal of developing a breakthrough carbon capture process that would enable both cement and lime industries to reduce their carbon dioxide (CO2) emissions dramatically.
Calix’s technology re-engineers the existing process flows of a traditional calciner, indirectly heating the limestone via a special steel vessel. This unique system enables pure CO2 to be captured as it is released from the limestone, as the furnace exhaust gases are kept separate. The solution requires no additional chemicals or processes, and minimal changes to the conventional processes for cement.
Watch this time lapse video of Project LEILAC’s structure construction from the beginning to the ribbon cutting – a significant step in enabling Direct Separation to become one of the principal methods of capturing the carbon emissions from the lime and cement industries… and another step towards Paris climate goals.
Calix’s solutions for Reducing CO2 Emissions help us contribute to many global goals, particularly SDG 13 – taking urgent action to combat climate change and its impacts.
Our Sustainability Series dives deeper into each of these challenges and explains how Calix contributes.Read our Sustainability Series