CO2 mineralization and utilization by alkaline solid wastes for potential carbon reduction

CO2 mineralization and utilization using alkaline solid wastes has been rapidly developed over the last ten years and is considered one of the promising technologies to stabilize solid wastes while combating global warming. Despite the publication of a number of reports evaluating the performance of the processes, no study on the estimation of the global CO2 reduction potential by CO2 mineralization and utilization using alkaline solid wastes has been reported. Here, we estimate global CO2 mitigation potentials facilitated by CO2 mineralization and utilization as a result of accelerated carbonation using various types of alkaline solid wastes in different regions of the world. We find that a substantial amount of CO2 (that is, 4.02 Gt per year) could be directly fixed and indirectly avoided by CO2 mineralization and utilization, corresponding to a reduction in global anthropogenic CO2 emissions of 12.5%. In particular, China exhibits the greatest potential worldwide to implement CO2 mineralization and utilization, where it would account for a notable reduction of up to 19.2% of China's annual total emissions. Our study reveals that CO2 mineralization and utilization using alkaline solid wastes should be regarded as one of the essential green technologies in the portfolio of strategic global CO2 mitigation. CO2 mineralization and utilization via alkaline solid wastes shows promise for both stabilizing solid waste and tackling climate change, but evidence of its actual CO2 reduction potential is scant. This study estimates that CO2 mineralization and utilization could lead to a 12.5% global reduction of CO2 emissions.