Preliminary Environmental and Economic Assessment of Mineral Carbonation of Steel Slags as a Carbon Capture, Utilization and Storage Technology

Abstract

To shift towards a sustainable steel production practice, circular economy principles can be applied in the value chain by valorizing the 2 in flue gases and the generated steel slags to produce stable silicates and carbonates via mineral carbonation, leading to long-term stable carbon sequestration. Carbonated slags can then be considered as a carbon capture, utilization and storage technology. However, it is important to quantify the environmental benefits and economic viability to evaluate a system's sustainability. This study aims (1) to evaluate the environmental and economic impacts of steel slag mineral carbonation and (2) to identify hotspots and process parameters of the systems. In this study, lab-scale experimental mineral carbonation data is upscaled to a TRL 6 scenario via an upscaling simulation with a power law learning curve. Subsequently, life cycle assessment and life cycle costing are performed to quantify the environmental and economic performances in agriculture. Contribution analyses are performed to ascertain the hotspots and process parameters of the systems. The results obtained in this study can encourage industrial symbiosis among different stakeholders in and around the steel industry to promote a more sustainable steel manufacturing value chain, incorporating circular economy principles.