A preliminary calculation of cement carbon dioxide in China from 1949 to 2050

Carbon dioxide (CO2) emissions from China are of global concern. As energy-, resource-intensive and greenhouse gas (GHG) pollution emissions, China’s cement-related CO2 emissions and environmental effect attracted more and more attention reasonably. A multiple-year’s cement CO2 emissions were estimated in China based on actual and projected cement output and CO2 emission factor (EF) from the perspective of technological improvement for the period 1949–2050. The more than 100 years’ time scale was divided into three periods: 1949–1979, 1980–2015, and 2016–2050, which mainly based on China’s socio-economy and technological improvement (i.e., transformed cement kilns and popularized waste heat recovery, WHR). The bottom-up model was used for calculating cement-related CO2 emissions after analyzing processes of cement production, and we found China’s comprehensive cement CO2 EF (CCEF) was about 1694.31 kg CO2 per ton of cement in 1949, and declined to 737.01 kg CO2 per ton of cement in 2015. Furthermore, it is likely that China’s cement output is about 1617.50 Mt in 2050. Meanwhile, China’s CCEF is about 576.02 kg CO2 per ton of cement which based on likely realistic scenario (LRS), and CO2 emissions are about 931.71 Mt in 2050, which is about half lower than those in 2014. It is important for calculating China’s cement emissions in the society and rank around the world. For China’s cement CO2 emission reduction, the contribution of technological innovation or improvement (TII) was undeniable, but the degree of CO2 reduction was limited, especially when the technological diffusion rate was close to saturation. The Chinese government is ambitious in controlling cement-related CO2 emissions and should start with controlling cement capacity, utilization of alternative raw materials (ARMs) and alternative fuels (AFs), and establishing a sound carbon trading market.