School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
Institute for Carbon Neutrality, University of Science and Technology Beijing, Beijing, 100083, China; Beijing Advanced Innovation Center for Materials Genome Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
J Environ Manage. 2023 Dec 15;348:119273. doi: 10.1016/j.jenvman.2023.119273. Epub 2023 Oct 11.
Maximizing the utilization of industrial by-products, such as iron ore tailings (IOTs) and coal fly ash (CFA), is crucial toward sustainable development. This study provides a meticulous insight into the optimization, mechanism, and assessment of the co-utilization of IOTs and CFA for the preparation of porous ceramsite. Micro-CT results revealed that the prepared ceramsite exhibited an exceptional porosity, peaking at 56.98%, with a wide range of pore diameters (3.55-959.10 μm) under optimal conditions (IOTs content at 76%, preheating at 550 °C for 15 min, and sintering at 1177 °C for 14 min), while maintaining good mechanical properties (water adsorption of 1.28%, comprehensive strength of 8.75 MPa, apparent density of 1.37 g/cm, and bulk density of 0.62 g/cm). The primary parameters affecting the porosity were identified and ranked as follows: sintering temperature > IOTs content > sintering time. The formation and growth of pores could be attributed to the equilibrium relationship between the liquid-phase surface tension and the gas expansion force, accompanied by pore wall thinning and pore merging. Notably, the prepared ceramsite is both ecologically feasible and economically rewarding, boasting a profit margin of 9.47 $/ton. The comprehensive life cycle assessment (LCA) conducted further highlights the potential of its large-scale implementation for promoting sustainable development. This study provides an innovative strategy for the co-utilization of IOTs and CFA, with advantages such as cost-effectiveness, ecological feasibility and scalability of production.
最大限度地利用工业副产品，如铁矿尾矿（IOT）和粉煤灰（CFA），对可持续发展至关重要。本研究深入探讨了优化、机理和评估 IOT 和 CFA 共用来制备多孔陶瓷的方法。微 CT 结果表明，在最佳条件下（IOT 含量为 76%，预热 15 分钟至 550°C，烧结 14 分钟至 1177°C），所制备的陶瓷具有出色的孔隙率，峰值达到 56.98%，孔径范围广泛（3.55-959.10 μm），同时保持良好的机械性能（吸水率为 1.28%，综合强度为 8.75 MPa，表观密度为 1.37 g/cm³，堆积密度为 0.62 g/cm³）。确定并对影响孔隙率的主要参数进行了排序，结果如下：烧结温度＞IOT 含量＞烧结时间。孔隙的形成和增长可归因于液相表面张力和气体膨胀力之间的平衡关系，同时伴随着孔壁变薄和孔合并。值得注意的是，所制备的陶瓷既具有生态可行性又具有经济回报，利润率为 9.47 美元/吨。进一步进行的综合生命周期评估（LCA）突出了其大规模实施促进可持续发展的潜力。本研究为 IOT 和 CFA 的共利用提供了一种创新策略，具有成本效益高、生态可行性好和生产规模化的优势。
