Narciso Murilo Miguel, Coelho Lisley Madeira, Monteiro Sergio Neves, Guimarães Antônio Carlos Rodrigues
Department of Fortification and Construction, Military Institute of Engineering-IME, Praça General Tibúrcio, 80, Urca, Rio de Janeiro 22290-270, Brazil.
Department of Materials Science, Military Institute of Engineering-IME, Praça General Tibúrcio, 80, Urca, Rio de Janeiro 22290-270, Brazil.
Materials (Basel). 2025 Jul 4;18(13):3180. doi: 10.3390/ma18133180.
Mining activities generate large volumes of tailings with significant environmental impact but also the potential for sustainable reuse in construction materials. This study evaluates the production of ceramic aggregates from mixtures of clay, sand, and iron ore waste subjected to thermal treatment at temperatures ranging from 600 to 1100 °C. The influence of calcination temperature on mineralogical transformations and mechanical integrity was investigated using X-ray diffraction (XRD) and the α-Treton parameter, derived from standardized impact resistance testing. The results indicate that the formation of metakaolinite between 700 and 900 °C enhances mechanical resistance, while higher temperatures (>900 °C) lead to structural degradation, followed by partial recovery due to mullite crystallization. The α-Treton curve exhibited clear correlation with the phase changes identified by XRD, demonstrating its applicability as a low-cost, sensitive proxy for optimizing thermal activation. A simplified methodology is proposed to optimize the thermal activation of such materials by correlating firing temperature with mineralogical evolution and mechanical integrity, contributing to the development of sustainable ceramic aggregates for pavement applications.
采矿活动产生大量尾矿，对环境影响重大，但也有在建筑材料中可持续再利用的潜力。本研究评估了在600至1100°C温度范围内对粘土、沙子和铁矿石废料混合物进行热处理后制备陶瓷骨料的情况。使用X射线衍射（XRD）和源自标准化抗冲击性测试的α-Treton参数，研究了煅烧温度对矿物学转变和机械完整性的影响。结果表明，700至900°C之间偏高岭土的形成增强了机械抗性，而更高温度（>900°C）会导致结构退化，随后由于莫来石结晶而部分恢复。α-Treton曲线与XRD确定的相变表现出明显相关性，证明其作为优化热活化的低成本、灵敏替代指标的适用性。提出了一种简化方法，通过将烧成温度与矿物学演变和机械完整性相关联，来优化此类材料的热活化，有助于开发用于路面应用的可持续陶瓷骨料。
