CO2 mineralisation
The mineralisation of carbon dioxide (CO2) can provide significant environmental benefits in a world where climate change is at the top of the agenda. For the cement industry, it is an option to lower that carbon footprint and supply an aggregate replacement to the concrete sector. This article explains the benefits and challenges faced by industry to turn CO2 mineralisation into a viable option. By John & Charles Kline, Kline Consulting LLC, USA.
Figure 1: relative abundance of elements that form carbonates in the earth’s crust
Mineral carbonation, or CO2 mineralisation, is the capture and permanent sequestration of CO2 as a mineral carbonate. This process is naturally occurring around the world as rocks weather. Certain minerals in the rocks combine with CO2 from the atmosphere to form natural mineral carbonates. In fact, concrete slowly decomposes over time according to the same mechanism. In concrete, CO2 from the atmosphere combines with the CaO from the concrete to form CaCO3.
