富铁污泥灰的制备及煅烧制度的确立

Preparation of Iron-Rich Sludge Ash and Establishment of Calcination System

摘要: 随着全球水泥生产量的不断增加，水泥行业的碳排放量也显著增长，而污水污泥焚烧产生的污泥灰因其含有SiO₂、Al₂O₃、CaO和Fe₂O₃等成分，被认为具有潜在的火山灰活性，可作为水泥的部分替代材料。本文针对广西某污水处理厂污泥，通过干燥、球磨及不同煅烧条件处理污泥样品，并采用物化分析方法探讨其火山灰活性。实验发现：煅烧温度显著影响污泥灰的比表面积、密度和微观结构，600℃为最佳煅烧温度；保温时间影响活性组分暴露和孔隙结构发展，最佳保温时间为2小时；比表面积的增大提高了污泥灰的反应界面，有利于增强其火山灰活性，但是过高的比表面积会增加需水量。通过优化煅烧制度，可制备性能优良的辅助胶凝材料，有效降低水泥使用量和碳排放。

Abstract: As global cement production continues to rise, so does the industry’s carbon emissions. Incineration of sewage sludge produces sludge ash containing SiO₂, Al₂O₃, CaO, and Fe₂O₃, which exhibits pozzolanic activity and can potentially replace a portion of cement. This study examined sludge from a wastewater treatment plant in Guangxi, treating samples via drying, ball milling, and various calcination conditions, followed by physicochemical analysis to assess pozzolanic activity. Key findings include: Calcination temperature significantly influences specific surface area, density, and microstructure, with 600˚C identified as the optimal temperature. Holding time affects exposure of reactive components and pore structure, with 2 hours being the ideal duration. Increased specific surface area enhances reaction interfaces, promoting pozzolanic activity; however, excessive surface area increases water demand. Optimizing calcination conditions can produce high-performance supplementary cementitious materials, reducing cement consumption and carbon emissions.