Wu Ximeng, Wang Haifeng, Guo Weichao, Wang Dong, Xue Caihong, Zhao Qingxin, Tang Jiaqiang, Pan Huimin
State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, 066004, Hebei, China; Hebei Province Engineering Research Center for Harmless Synergistic Treatment and Recycling of Municipal Solid Waste, Yanshan University, Qinhuangdao, 066004, Hebei, China.
Cangzhou Qugang Expressway Construction CO. Ltd., Cangzhou, 062450, Hebei, China.
Environ Res. 2025 Jun 20;284:122180. doi: 10.1016/j.envres.2025.122180.
With the rapid economic growth and accelerated urbanization, solid waste recycling has become a critical priority for eco-friendly urban development. Although some studies have investigated cold-bonded aggregates using MSWIFA, the effect of curing environments on heavy metal immobilization and mechanical behavior remains poorly understood. This study utilizes solid wastes such as municipal solid waste incineration fly ash (MSWIFA) and carbide slag to produce environmentally friendly non-sintered lightweight aggregates, and the effect of curing temperature and solution on the properties, reaction products as well as heavy metal leaching was investigated. The results show that under steam curing at 60 °C for 12 h, using calcium carbide slag supernatant as the granulation solution, the mechanical strength of the aggregates reached more than 7.02 MPa, meeting the Chinese standards for lightweight aggregates. Steam curing promotes the formation of hydrocalumite minerals, but the peak gradually weakens when the curing temperature reaches 75 °C. Microstructural analysis through XRD, FTIR, SEM, and XPS revealed that high temperatures activated the latent reactivity of slag, accelerating the reactions and promoting the generation of more C-S-H gel and hydrated calcium aluminates. This study proposes an innovative use of MSWIFA and carbide slag to produce non-sintered aggregates and systematically evaluates their performance under various curing conditions. The results are validated by detailed characterization, confirming both the originality and reliability of the work. In conclusion, the non-sintered lightweight aggregates prepared from MSWIFA demonstrate good mechanical performance and environmental adaptability, providing a sustainable alternative to natural aggregates and a useful reference for eco-friendly construction materials.
随着经济的快速增长和城市化进程的加速，固体废物回收利用已成为生态友好型城市发展的关键优先事项。尽管一些研究已使用城市固体废弃物焚烧飞灰（MSWIFA）对冷粘结骨料进行了调查，但养护环境对重金属固定化和力学行为的影响仍知之甚少。本研究利用城市固体废弃物焚烧飞灰（MSWIFA）和电石渣等固体废物生产环保型非烧结轻质骨料，并研究了养护温度和溶液对其性能、反应产物以及重金属浸出的影响。结果表明，在60℃蒸汽养护12小时的条件下，使用电石渣上清液作为造粒溶液，骨料的机械强度达到7.02MPa以上，符合中国轻质骨料标准。蒸汽养护促进了碳铝钙石矿物的形成，但当养护温度达到75℃时，该峰逐渐减弱。通过XRD、FTIR、SEM和XPS进行的微观结构分析表明，高温激活了矿渣的潜在反应活性，加速了反应并促进了更多C-S-H凝胶和水化铝酸钙的生成。本研究提出了一种创新方法，利用MSWIFA和电石渣生产非烧结骨料，并系统评估了它们在各种养护条件下的性能。通过详细表征验证了结果，证实了该工作的原创性和可靠性。总之，由MSWIFA制备的非烧结轻质骨料具有良好的力学性能和环境适应性，为天然骨料提供了可持续的替代品，并为生态友好型建筑材料提供了有益的参考。
