Harnessing the heat and material potential in steel slag to decarbonize China’s steel industry

作者：Yiwen Lv, Junjun Wu, Zhen Han, Yuhao Xiang, Zhenyu Sun, Xiaohuan Liu, Hong Wang, Wei Ren, Xun Guo Zhu, Qiang Liao · 发表于：Carbon Neutrality · 年份：2026 · DOI：10.1007/s43979-026-00179-6 · 研究领域：Recycling and utilization of industrial and municipal waste in materials production、Metallurgical Processes and Thermodynamics、Iron and Steelmaking Processes

Abstract The steel industry generates hundreds of millions of tons of steel slag (SS), with < 30% recycled in China due to its recalcitrant properties. Herein, we introduce a co-processing approach, modifying the molten SS with low-cost blast furnace slag (BFS) and sands to recover heat and produce cementitious materials. Such modification reduces SS viscosity by 83% (0.5 Pa·s) and free CaO to < 2%, enabling 75% thermal recovery efficiency (50% higher than conventional methods). Moreover, the final slag beads are nearly 100% glassy, suitable for cement production. Energy-economic assessment confirms its carbon-negative nature with heat and material potential being fully exploited. Scaling this technology across Chinese steel plants could yield $8.7 billion annual revenue and reduce 82 Mt CO 2 emissions (9.4% sectoral total) through heat reuse and clinker substitution. This work provides a potential pathway to the “hard-to-use” SS waste streams and advances the circular economy in China’s metallurgical industry.