Cement Industry

The cement industry accounts for approximately 5 percent of current anthropogenic carbon dioxide (CO2)emissions worldwide. World cement demand and production are increasing; annual world cement production is expected to grow from approximately 2,540 million tonnes (Mt) in 2006 to between 3,680 Mt (low estimate) and 4,380 Mt (high estimate) in 2050. The largest share of this growth will take place in China, India, and other developing countries on the Asian continent. This significant increase in cement production is associated with a significant increase in the cement industry’s absolute energy use and CO2 emissions.

China's cement industry, which produced 1,868 million metric tons (Mt) of cement in 2010, accounts for nearly half of the world’s total cement production. In 2010, nearly 20% of China’s current cement production was from relatively obsolete vertical shaft kiln (VSK) cement plants, with the remainder from modern rotary kiln cement plants, including plants equipped with new suspension pre-heater and pre-calciner (NSP) kilns. To accelerate kiln technology switch, official Chinese government policy calls for the phase-out and replacement of all VSK cement plants with more modern kilns.

The production of 1 metric ton (t) of cement releases an estimated 0.73 to 0.99 t CO2/t cement depending on the clinker-per-cement ratio and other factors. A major difference between the cement industry and most other industries is that fuel consumption is not the dominant driver of CO2 emissions from cement production. More than 50 percent of the CO2 released during cement manufacture, or approximately 540 kg CO2 per t of clinker, is from calcination in which limestone (CaCO3) is transformed into lime (CaO).