Calculation model for CO2 emissions of blended cement production

The production of cement blended with supplementary cementitious materials (SCMs) is efficient in reducing the clinker content, which could reduce the CO2 emissions of cement production. However, the reduction ratio of CO2 emissions caused by this method is hard to quantify yet, because the incorporation of SCMs could result in extra CO2 emissions during processes such as milling. This study aims to quantify the CO2 emissions reduction potential of blended cement production incorporating SCMs, which effectively lowers clinker content. To address this gap, we developed a comprehensive CO2 emissions calculation model for blended cement production. The model encompasses four key modules: process, fuel, electricity, and transport, enabling the systematic quantification of emissions from carbonate decomposition, fuel combustion, electricity consumption, and transportation. A novel aspect of our model is its ability to calculate electricity consumption during cement grinding for various particle sizes, offering a more nuanced understanding of the energy efficiency in the production process. By applying this model, we analyzed the proportion of CO2 emissions from different sources in Portland cement production, validating our approach against the “China Cement Manufacturing Enterprises' Greenhouse Gas Emission Accounting Methods and Reporting Guidelines (Trial)."Crucially, our model was further utilized to simulate the CO2 emissions across the entire production process of blended cement with varying clinker contents. The findings reveal that, compared to OPC, the production of blended cement with 70% and 25% clinker content can achieve CO2 emissions reductions of 22.46% and 60.64% respectively. These results underscore the significant potential of SCMs in mitigating the environmental footprint of cement production. •Established a calculation model for the CO2 emissions throughout the entire process of blended cement production.•Provided the calculation of power consumption for cement grinding of different particle sizes.•Quantified carbon reduction efficacy of blended cement compared to OPC.