Stainable Utilization Strategies for Basic Oxygen Furnace Slag: Properties, Processing, and Future Directions

Abstract

Steel slag, being the dominant solid byproduct in steelmaking, presents global challenges in sustainable management, particularly regarding resource recovery of Basic Oxygen Furnace (BOF) slag, which accounts for over 72% of total slag generation. Through the databases of ScienceDirect, Web of Science, and CNKI, using relevant key words, this review systematically investigates the physicochemical properties and mineralogical composition of BOF slag, elucidating the intrinsic mechanisms underlying its low hydration reactivity and volumetric instability. Pretreatment techniques have been demonstrated to effectively modulate these properties. Furthermore, valuable components can be efficiently recovered through methods including magnetic separation and related technologies. Furthermore, this review elucidates the mechanisms and existing challenges across various resource utilization approaches for steel slag, while also identifying key research priorities for future development, thereby providing a systematic theoretical framework and technical pathways to advance utilization of steel slag.