The worldwide anthropogenic emissions of CO2 in 2013 were estimated at 37Gt, according to the IPCC and IEA, including the cement industry’s contribution of 2-2.5Gta, ie 5.5-6.5 per cent of the world total. Therefore, it is key that the cement industry develops new products and technologies that mitigate its CO2 emissions. Over the last nine years, Lafarge has been leading or participating in this initiative.
Portland clinker is produced via a combustion process that sees limestone (calcium carbonate) from the quarry calcined to lime, which then combines with clay to produce the clinker. This process requires thermal energy, eg 2.9GJ/t clinker with the best available technology (BAT). The CO2 emission related to both calcination and combustion is ~ 830kg CO2/t clinker produced.
