Zero-Emission Cement Plants with Advanced Amine-Based CO₂ Capture

Decarbonization of the cement sector is essentially required to achieve carbon neutrality to combat climate change. Amine-based CO₂ capture is a leading and practical technology to deeply remove CO₂ from the cement industry, owing to its high retrofittability to existing cement plants and extensive engineering experience in industrial flue gas decarbonization. While research efforts have been made to achieve low-carbon cement with 90% CO₂ removal, a net-zero-emission cement plant that will be required for a carbon neutrality society has not yet been investigated. The present study proposed an advanced amine-based CO₂ capture system integrated with a cement plant to achieve net-zero CO₂ emission by pushing the CO₂ capture efficiency to 99.7%. Monoethanomaine (MEA) and piperazine/2-amino-2-methyl-1-propanol (PZ-AMP) amine systems, which are considered to be the first- and second-generation capture agents, respectively, were detailed investigated to deeply decarbonize the cement plant. Compared to MEA, the advanced PZ-AMP system exhibited excellent energy performance with a regeneration duty of ∼2.6 GJ/tonne CO₂ at 99.7% capture, 39% lower than the MEA process. This enabled a low CO₂ avoided cost of $72.0/tonne CO₂, which was 18% lower than that of the MEA-based zero-emission process and even 16.2% lower than the standard 90% MEA process. Sensitivity analysis revealed that the zero-emission capture cost of the PZ-AMP system would be further reduced to below $56/tonne CO₂ at a $4/GJ steam production cost, indicating its economic competitiveness among various CO₂ capture technologies to achieve a zero-emission cement plant.