High‑temperature thermal storage‑based cement manufacturing for decarbonization

Cost-effective CO_(2) capture is essential for decarbonized cement production since it is one of the largest CO_(2) emission sources,where 60%of direct emissions are from CaCO3 decomposition and 40%are from fuel combustion.This work presents a low-carbon cement manufacturing process by integrating it with renewable energy for electric heating and thermal storage to replace the burning of fossil fuels in the conventional calciner.The low-carbon renewable energy reduces the indirect CO_(2) emissions from electricity consumption.The high-temperature CO_(2) is employed as the heat transfer fluid between the energy storage system and the calciner.In the proposed basic manufacturing process,the CO_(2) from the CaCO3 decomposition can be directly collected without energy-consuming separation since no impurities are introduced.Furthermore,the remaining CO_(2) from fuel combustion in the kiln can be captured through monoethanolamine(MEA)absorption using waste heat.In the two situations,the overall CO_(2) emissions can be reduced by 69.7% and 83.1%,respectively,including the indirect emissions of electricity consumption.The economic performance of different energy storage materials is investigated for materials selection.The proposed manufacturing process with a few high-temperature energy storage materials(BaCO_(3)/BaO,SrCO_(3)/SrO,Si,etc.)offers a higher CO_(2) emission reduction and lower cost than alternative carbon capture routes,i.e.,oxyfuel.The cost of CO_(2) avoided as low as 39.27$/t can be achieved by thermochemical energy storage with BaCO_(3)/BaO at 1300℃,which is superior to all alternative technologies evaluated in recent studies.