Peng Biao, Wang Lusen, Li Zhonglin, Xu Ye, Zhang Weiguang, Li Yibing
Department of Materials Science and Engineering, Guilin University of Technology, Guilin 541004, China.
Materials (Basel). 2025 Mar 10;18(6):1218. doi: 10.3390/ma18061218.
A novel composite cementitious material was constructed by synergistically utilizing multiple industrial solid wastes, including electrolytic manganese residue (EMR), red mud (RM), and ground granulated blast furnace slag (GGBS), with calcium hydroxide [Ca(OH)] as an alkaline activator. In addition, the mechanical properties of the composite cementitious materials were systematically analyzed under different raw material ratios, alkali activator dosages, and water-binder ratios. To further investigate the hydration products and mechanisms of the composite cementitious material, characterization methods, for instance, XRD, FT-IR, SEM-EDS, and TG-DTG, were employed to characterize the materials. To ensure that the composite cementitious material does not cause additional environmental pressure, it was analyzed for toxic leaching. The relevant experimental results indicate that the optimal ratio of the EMR-RM-GGBS-Ca(OH) components of the composite cementitious material is EMR content of 20%, RM content of 15%, GGBS content of 52%, calcium hydroxide as alkali activator content of 13%, and water-binder ratio of 0.5. Under the optimal ratio, the composite cementitious material at 28 days exhibited a compressive strength of 27.9 MPa, as well as a flexural strength of 7.5 MPa. The hydration products in the as-synthesized composite cementitious material system primarily encompassed ettringite (AFt) and hydrated calcium silicate (C-S-H), and their tight bonding in the middle and later curing stages was the main source of engineering mechanical strength. The heavy metal concentrations in the 28-day leaching solution of the EMR-RM-GGBS-Ca(OH) composite cementitious material fall within the limits prescribed by the drinking water hygiene standard (GB5749-2022), indicating that this composite material exhibits satisfactory safety performance. To sum up, it is elucidated that the novel process involved in this research provide useful references for the pollution-free treatment and resource utilization of solid wastes such as red mud and electrolytic manganese residue in the future.
通过协同利用多种工业固体废弃物，包括电解锰渣（EMR）、赤泥（RM）和磨细粒化高炉矿渣（GGBS），并以氢氧化钙[Ca(OH)]作为碱性激发剂，构建了一种新型复合胶凝材料。此外，还系统分析了不同原料配比、碱激发剂用量和水胶比下复合胶凝材料的力学性能。为进一步研究复合胶凝材料的水化产物和机理，采用XRD、FT-IR、SEM-EDS和TG-DTG等表征方法对材料进行表征。为确保复合胶凝材料不会造成额外的环境压力，对其进行了有毒浸出分析。相关实验结果表明，复合胶凝材料中EMR-RM-GGBS-Ca(OH)组分的最佳配比为：EMR含量20%、RM含量15%、GGBS含量52%、氢氧化钙作为碱激发剂含量13%、水胶比0.5。在最佳配比下，28天龄期的复合胶凝材料抗压强度为27.9MPa，抗折强度为7.5MPa。合成的复合胶凝材料体系中的水化产物主要包括钙矾石（AFt）和水化硅酸钙（C-S-H），它们在中后期养护阶段的紧密结合是工程力学强度的主要来源。EMR-RM-GGBS-Ca(OH)复合胶凝材料28天浸出液中的重金属浓度符合《生活饮用水卫生标准》（GB5749-2022）规定的限值，表明该复合材料具有良好的安全性能。综上所述，本研究涉及的新工艺为今后赤泥、电解锰渣等固体废弃物的无害化处理和资源利用提供了有益参考。
