Replacing Calcination with Electrochemical Decarbonation: A Life Cycle Perspective for Cement Production

Cement manufacturing traditionally relies on the decarbonation of raw materials, mainly calcium carbonate (CaCO₃), obtained from limestone and other calcareous rocks. In conventional processes, this reaction occurs through calcination in high-temperature kilns, releasing large amounts of CO₂, representing nearly 8% of global emissions from the construction sector. In line with the United Nations Sustainable Development Goals, which target net-zero greenhouse gas emissions by 2050, the cement industry is exploring alternative, cleaner production methods for clinker. This study evaluates the potential of replacing the thermal decomposition of materials that provide CaCO₃ with an electrochemical decarbonation process carried out in an H-type electrochemical cell equipped with an ion-exchange membrane. Direct current from a regulated power supply drives the reaction, producing Ca(OH)₂ as a solid precipitate, while generating pure streams of H₂, O₂, and CO₂. The gases can be collected using sealed gas sampling systems for subsequent utilization in clean energy applications or industrial processes. This substitution not only reduces the carbon footprint of the cement industry by enabling CO₂ capture at the point of generation but also yields a reactive Ca(OH)₂ suitable for clinker production. The process is currently at the laboratory scale, with ongoing analysis focusing on reaction efficiency, gas yield, and the economic feasibility of producing one ton of cement using this method, thereby delivering valuable insights into its potential large-scale implementation.