Economic and Low-Carbon Cementitious Materials Based on Hot–Stuffy Steel Slag

作者：Xupeng Zhang, Chonghao Xu, Mingze Wang, Shiyu Du, Yan Li, Guoqing Wang · 发表于：Buildings · 年份：2025 · DOI：10.3390/buildings15162931 · 被引用次数：1 · 研究领域：Concrete and Cement Materials Research、Magnesium Oxide Properties and Applications、Recycling and utilization of industrial and municipal waste in materials production

Ordinary steel slag serves as a supplementary cementitious material (SCMs) to enhance the resource efficiency of industrial waste and contribute to decarbonization and economic benefits. However, there are significant differences in the composition and properties between hot–stuffy steel slag and ordinary steel slag, and there has been little research focusing on hot–stuffy steel slag as an SCM. Herein, we investigated the application of hot–stuffy steel slag, coal bottom ash, slag powder, desulfurization gypsum, and cement as raw materials for developing new green, low-carbon, and economical cementitious materials. When the hot–stuffy steel slag content was 20%, the compressive and flexural strengths of the cementitious material at 28 days reached as high as 64.5 MPa and 11.3 MPa, respectively. Even when the hot–stuffy steel slag content is increased to 50%, the compressive and flexural strengths at 28 days remain 58.2 MPa and 6.1 MPa, respectively. Furthermore, an X-ray diffractometer (XRD) and scanning electron microscopy (SEM) show that the hydration products generated by the new low-carbon cementitious materials (LCM) are mainly C-(A)-S-H gels. Mercury intrusion porosimetry (MIP) indicates that when the hot–stuffy steel slag content is 20%, the total porosity (18.85%) of the LCM is the lowest, suggesting that the lower the porosity, the better the strength. Notably, the heavy metal ions released by hot–stuffy steel slag-based cementitious materials were far below hygieni...