Quantifying the CO2 Reduction Potential of CO2 Curing over Autoclave Curing for Calcium Silicate Boards: A Carbon Footprint Quantification

Calcium silicate boards, as a type of prefabricated building component, are widely used in the construction industry. To address the severe challenges posed by global climate change and support the low-carbon transition of the building materials sector, this study quantifies and compares the differences in carbon emissions between traditional autoclave curing and carbon dioxide mineralization curing during the production of calcium silicate boards, and conducts an uncertainty analysis. Using a project-based accounting methodology and incorporating actual CO2 sequestration measurement data obtained via the weighing method, this study calculated carbon emissions during the calcium silicate board production process and performed scenario analysis to account for uncertainties in emission factors. The study found that, compared to autoclave curing production lines, CO2 mineralization curing production lines can reduce carbon emissions by approximately 1007 t CO2; when CO2 sequestration is factored in, the reduction is approximately 3097 t CO2. Even under the most pessimistic scenario, CO2 mineralization curing production lines can reduce carbon emissions by at least 977 t CO2, demonstrating significant emission reduction benefits. This study provides regionally representative quantitative data that supports the low-carbon transition of calcium silicate boards and holds significant practical implications for promoting the reduction in embodied carbon emissions in the building materials industry and achieving the “dual carbon” goals.