Feasibility Assessment of CO₂ Capture Retrofitted to an Existing Cement Plant: Post-combustion vs. Oxy-fuel Combustion Technology

This research presents a preliminary techno-economic evaluation of CO₂ capture integrated with a cement plant. Two capture technologies are evaluated, monoethanolamine (MEA) post-combustion CO₂ capture and oxy-fuel combustion. Both are considered potential technologies that could contribute to reduction of CO₂ emissions in the cement industry. The study compares these two technologies in terms of technical performance, investment costs, and operational costs. The case study is applied to the one of the largest cement plants in Portugal, Alhandra. The results show that the amount of CO₂ avoided using the post-combustion MEA technology is lower due to additional emissions from reboiler steam production. Moreover, the total capital investment of the post-combustion CO₂ capture system is estimated at 260 M€₂₀₁₄ and the annual operation and maintenance costs of around 43 M€₂₀₁₄; whereas the oxy-fuel combustion CO₂ capture requires a capital investment of about 217 M€₂₀₁₄ and 37 M€₂₀₁₄ annually for operation and maintenance. This indicates that the oxy-fuel CO₂ capture technology may be a better choice in terms of costs. However, this technology implies higher technical uncertainties concerning integration with the cement plant.