How to minimise the carbon emission of steel building products from a cradle-to-site perspective: A systematic review of recent global research

Steel is the second-most commonly used building material, after concrete, which results in considerable amount of carbon emission. Growing number of studies have explored the opportunities of minimising the carbon emission of steel building products. Numbers of carbon reduction strategies (CRSs), such as coke dry quenching technology, blast furnace off gas recovery measures, biomass energy, and carbon capture technology have been proposed and investigated. Owing to the different aims, scopes, and methods of the existing studies, they have led to mixed conclusions and a question has been frequently asked: how to efficiently minimise the carbon emission of steel building products, especially from a cradle-to-site perspective? Therefore, the present study systematically reviews and critically analyses the relevant research literature. 286 peer-reviewed studies have been reviewed and 12 categories of CRSs have been identified. The most frequently studied CRSs include the recovery of furnace gas and waste heat, use of alternative fuels and energy, alternative/improved ironmaking technologies and etc. However, it is found that these studies have largely ignored the CRSs applicable to the upstream and downstream manufacturing processes, and have insufficiently examined, especially from a quantitative perspective, the carbon emission reduction potential of policy drivers and the cumulative effects of multiple CRSs. The results of this review also reveal the steady growth of research interest in this field with the significant research contributions made by Chinese academia. Last but not least, the best available technologies have been fully investigated in the reviewed literature, while the emerging cleaner production technologies, such as electrification of ironmaking, carbon capture and storage, clean fuel and energy, yet demand further investigation. The findings presented herein is expected to guide future research direction in this field and also to assist industry practitioners to formulate efficient CRSs.