Techno-economic assessment of a cement production plant integrated with solid oxide electrolysis for CO2-to-CO conversion and waste-heat recovery

Decarbonizing cement production plants (CPPs) remains a major challenge due to unavoidable CO2 emissions from the calcination process. In this study, a novel hybrid CPP system integrated with solid oxide electrolysis cells (SOECs) is proposed and analyzed to convert captured CO2 into CO, which reduces CO2 emission of CPPs by 75.17%. Two configurations were evaluated: a base system and an enhanced system incorporating waste-heat recovery through three Rankine cycles (TRC). A validated process model was employed to perform comprehensive techno-economic analyses, including net present value (NPV) estimation, sensitivity analysis and Monte Carlo simulation to account for parametric uncertainties. The levelized cost of CO was determined as 1.744 and 1.735 USD kg−1 CO for the base and TRC-integrated systems, respectively. The TRC integration improved system efficiency and reduced electricity demand, resulting in enhanced economic performance despite slightly higher capital costs. Sensitivity analysis identified the capacity factor and tax rate as the most influential parameters, while uncertainty analysis confirmed economic robustness with a 68.3-94.6% probability of positive NPV under current market conditions. These findings demonstrate that coupling CPPs with high-temperature SOECs and waste-heat recovery cycles offers a technically and economically viable, scalable pathway toward carbon-neutral cement manufacturing.