Cement is the second most consumed substance on Earth after water, fulfilling an essential role in providing society’s need for housing and infrastructure while lime is used in a variety of applications including in the iron & steel, chemical, paper and pharmaceutical industries. Both sectors have relatively high carbon dioxide (CO2) emissions.
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.Learn more
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.
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.
Project LEILAC (Low Emissions Intensity Lime And Cement) is supported with €12 million from EU research funds, and involves a consortium, lead by Calix, that includes industrial heavyweights HeidelbergCement, Cemex, Lhoist and Tarmac.
Simon Thomsen, Calix Project Engineer explains how Calix applied its technology to the cement and lime industries, by increasing the temperature, and improving the efficiency, performance and operativity of the process.
Mark Sceats, Calix Chief Scientist, discusses the evolution of the Calix Technology behind Project LEILAC and the value of a collaborative approach with industry “the involvement of industry is absolutely critical” he says.