Around 3 Billion tons of cement are produced every year accounting for 10-15 % of global energy usage in industry and up to 10 % of global CO2 production. The continuing growth of developing nations is creating an ever growing demand for cement, which means energy use and CO2 production will only increase. This brings inherent cost and environmental social responsibility concerns.
Around half of the CO2 emissions associated with cement production come from the calcination of limestone. The calcination of limestone produces clinker, which when mixed with gypsum is known as Portland cement and is generally the main ingredient of cements and concretes used today.
However, cement has not always been based on Portland cement, Pozzolan-lime cements were used by the Romans. Roman structures made using Pozzolan based cements are still standing after 2000 years, perhaps most famously the Pantheon in Rome. Pozzolan cements develop strength slowly, they are slower to set which makes Pozzolan cement easier to work with when first poured, but over time Pozzolan cements become stronger than Portland cement.
Increasingly industrial cement production is using Pozzolan materials such as fly-ash and volcanic-ash, to replace a proportion of the Portland cement. This reduces CO2 emissions and cost but doing so can also have beneficial effects as shown by the longevity of the Pantheon. Further understanding the cement product at the particle level can help maximize the benefits and minimize the costs.
Using the Morphologi G3-ID the size and shape of various components in a cement blend can be individually characterized by morphologically directed Raman analysis. Results can be used to compare batches or products, to aid the understanding of product development or to solve a production problem.
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