Combined electrification and carbon capture for low-carbon cement: Techno-economic assessment of different designs
Leonardo Varnier, Federico d’Amore, K. N. Clausen, George Melitos, B. de Groot, Fabrizio Bezzo
Abstract
The cement industry is a major contributor to global CO 2 emissions. Among the various decarbonisation strategies, heat demand electrification and carbon capture technologies offer promising solutions for reducing both process- and fuel-related emissions. This study investigates the potential of low-carbon cement plants that combine calciner electrification with amine-based carbon capture on rotary kiln emissions. A techno-economic analysis is conducted on four process alternatives, differing in the type of electrified calciner – entrainment vs. drop tube – and the heat recovery strategy for the hot CO 2 produced, in the EU context. The four low-carbon processes are benchmarked against a reference plant without mitigation measures. Drop tube calciner configurations show better energy efficiency than entrainment calciner alternatives although their environmental performance is comparable. When renewable electrical energy is supplied to the plants, the CO 2 avoidance rates exceed 98%, making these options competitive with other decarbonisation technologies such as oxyfuel and calcium looping. Economic viability remains challenging under current EU prices and carbon intensity of imported electricity. The entrainment calciner configuration that uses pure CO 2 to preheat raw materials emerges as the most favourable, with a cost of avoided CO 2 of 217.4 €/t CO2 , compared to 231–234 €/t CO2 for the other options. To ensure cost-effectiveness, electricity prices would need to remain below approximately 90 €/MWh el when low-carbon electricity is supplied. • Combined calciner electrification and amine-based carbon capture is assessed. • CO 2 avoidance rate is larger than 98% when renewable electricity is supplied. • CO 2 avoided cost ranges between 217 and 234 €/t CO2 , mainly driven by electricity cost. • EU electricity prices of 125 €/MWh make the technology economically unviable. • Affordable and low-carbon electricity is crucial to ensure cost-effectiveness.