Ultrafast belite (β‐C ₂ S) production using biofuel‐based combustion synthesis

Abstract This study presents a novel low‐temperature, combustion synthesis (CS) approach for the rapid production of belite‐rich cements. CS leverages the exothermic heat released from the combustion of biofuels such as lignin and/or biomass, intermixed with pelletized limestone and quartz. At an imposed furnace temperature of ∼700°C (as opposed to 1200°C–1300°C required in a conventional kiln), the source materials are rapidly transformed to belite, resulting in energy, emissions, and economic benefits. This work explores the influence of various process parameters, viz., fuel types and contents, airflow rate, porosity, holding temperature, and holding time on the efficiency of CS‐based belite synthesis. Through careful optimization of these parameters, including through machine learning‐based methods, >90% belite content is obtained in the synthesized pellets. Advanced analytical tests show that the belite produced from CS closely resembles that obtained from traditional high‐temperature processing. CS has the potential to significantly reduce energy consumption and emissions associated with belite production, and to accelerate the synthesis process by three‐to‐four times as compared to the conventional method.