Cement and its emissions

Concrete is said to be the second-most used substance in the world, after water, and the glue that binds concrete together is cement. Producing cement results in substantial emissions of CO2, both from the use of fossil fuels, but also, and in fact more importantly, from the chemical process itself. Cement is made from limestone (CaCO3), which when heated breaks down into lime (CaO) and CO2. Global emissions datasets usually quantify emissions from fossil fuels first and then add in other categories, so it's important to have a good estimate of these process emissions from cement production.

Global cement process emissions

As part of the Global Carbon Budget fossil CO2 dataset, I produce an independent dataset of the emissions from production of cement clinker for every country. These are the so-called "process" emissions, which result from the decomposition of carbonates (particularly limestone), and are separate from the use of fossil fuels.

The dataset is archived on the Zenodo permanent European science data repository here.

The repository also includes collated annual data on cement and cement clinker production by country, which are otherwise not easy to find assembled in one place.

The chart here shows the process emissions from this dataset added up over all countries, and a rough estimate of the emissions from use of fossil fuels in cement production, for comparision. The decline in recent years is a direct result of China's property sector bust.

Monthly cement activity data

As one of the inputs to the global cement process emissions dataset, I maintain a dataset of monthly activity data, collated from many sources. The dataset includes only data as reported, either directly by official agencies or cement associations, or as reported to the UN and published in their (now discontinued) monthly statistical bulletin series.

The dataset is archived on the Zenodo permanent European science data repository here.

The dataset is updated much more frequently than it is published on the Zenodo archive. If you have an interest in using more up-to-date data than is available there, then please contact me.

Mitigation

There are a lot of ways to reduce the emissions in cement production, but much work is still required. This deck of 25 slides presents some information about the different mitigation approaches that are currently available. Click to view.