Opportunities for cement decarbonization

Abstract

In the sixth IPCC assessment report, it is recommended to decarbonize the economy to avoid a global average temperature increase of 1.5 °C by 2100 and some of the most catastrophic effects of climate change. Today, the production of cement makes up roughly 5–8% (∼2.3 GtCO2/yr) of all global carbon dioxide (CO2) emissions. Of these emissions, nearly 67 MtCO2/yr come from the United States. The cement sector faces a unique challenge in decarbonizing operations because the CO2 emitted originates from the use of fossil fuels in the high-temperature calcination step (∼40% emissions) and from the chemistry of limestone (CaCO3) breaking down into lime (CaO) and CO2 (∼60% emissions). In addition, expensive changes to the process or product within the cement industry can be very detrimental to profitability. This study provides an overview of the incumbent methodology for cement production as well as specific pathways towards decarbonization that are emerging for the cement industry. A technology-agnostic cost model is used to estimate the cost of carbon capture and storage (CCS) for all the cement plants in Texas and Florida, two of the highest capacity cement producing states in the United States. Further, geospatial case studies for these states are presented to illustrate how the co-location of resources, such as CO2 storage opportunities, can inform which technologies may be the most compatible with commercial scaling.