Retrofitting Ordinary Portland cement production for reduced greenhouse gas emissions

Cement production is an energy-intensive process and a major greenhouse gas (GHG) emitter. Carbon capture, utilization and storage (CCUS) technologies and fossil fuel substitution have been studied as carbon mitigation measures in the cement industry. However, their optimal combination for retrofitting the production of Ordinary Portland cement (OPC) has yet to be assessed. We formulate and optimize a superstructure to retrofit the OPC production by optimally combining CCUS technologies and fuel switching. Our analysis shows that the emerging Pareto-optimal designs heavily depend on the local conditions, notably the availability of biomass and carbon storage, electricity prices, and emission factor of the used electricity mix. Economically, carbon capture and storage (CCS) is more cost-effective than carbon capture and utilization (CCU) via power-to-methane at current costs in Germany. Only if renewable electricity can be accessed at very low cost, CCU becomes an attractive option.