The Chinese cement industry has already made improvements in energy efficiency, but the emission reductions from energy efficiency measures are tiny compared to those that could be achieved with innovative technologies.
China makes more Cement than the rest of the world, in fact:
- China products 2,400,000 thousand metric tons;
- the rest of the world 1,728,300 thousand metric tons.
The more important problem with reducing emission from cement industry is the production of clinker, the key ingredient in cement, and to get clinker you need lime. The most common way of getting it is through a process known as calcination, in which limestone (CaCO3) is heated to around 1400C in a cement kiln breaking it down into lime.
About 40% of emissions have traditionally come from burning fossil fuels to heat kilns (with the final 5-10% accounted for by operations and transport). This means there is significant scope to reduce overall cement emissions by finding alternative fuels.
To heat a cement kiln with waste requires about three times as much as coal, and can reduce emissions by around 10%. This, when combined with better waste management, the benefits of using waste in cement production are not negligible either.
China’s municipal solid waste is set to grow at a rate of 8-10% each year, increasing the amount of waste used in cement-making should be of interest to Chinese policymakers.
The largest cement producers in China have already started developing “co-processing” technologies that bring cola alternatives into the production fuel mix.
Galbiati Group manufactures the main and auxiliary gears drives for mills and kilns for cement industry. For more information visit the website www.galbiatigroup.it