摘要
磷石膏是湿法磷酸生产过程中的大宗固废,因其高含水率、耐水性差和力学性能低,限制了其在建筑材料中的应用。为提升其胶凝性能,构建了磷石膏-水泥-矿渣-偏高岭土四元胶凝体系,研究矿渣、水泥、水玻璃掺量及其模数对力学性能的影响。结果表明,矿渣和水泥协同作用可显著提高材料强度,最佳参数为矿渣10%、水泥20%、水玻璃0.8%、模数0.16。在此条件下,材料抗压与抗折强度大幅提升。XRD分析表明主要水化产物为C-S-H凝胶、AFt和硅铝聚合物;FTIR检测到Si-O-Si, Al-O-Si等结构键增强;SEM显示水化产物致密填充孔隙,形成完整骨架结构。该研究成果为磷石膏高值资源化及绿色胶凝材料开发提供了理论依据与技术支撑。
Phosphogypsum,a bulk solid waste generated during wet-process phosphoric acid production,suffers from high moisture content,poor water resistance,and low mechanical performance,which constrain its application in construction materials.To enhance its cementitious properties,a quaternary binder system comprising phosphogypsum,cement,slag,and metakaolin was developed,and the effects of slag content,cement content,sodium silicate dosage,and its modulus on mechanical performance were investigated.Results indicate that synergistic activation by slag and cement significantly improves material strength,with optimal parameters found at 10%slag,20%cement,and 0.8%sodium silicate(modulus 0.16).Under these conditions,both compressive and flexural strengths increased markedly.Xray diffraction(XRD)analysis identified Calcium Silicate Hydrate(C-S-H)Gel,ettringite(AFt),and aluminosilicate phases as the primary hydration products.Fourier Transform Infrared Spectroscopy(FTIR)detected strengthened Si-O-Si and Al-O-Si structural bonds,while Scanning Electron Microscopy(SEM)revealed that the dense network of hydration products filled pore spaces and formed an integral skeletal structure.These findings provide theoretical guidance and technical support for the high-value resource utilization of phosphogypsum and the development of ecofriendly cementitious materials.
作者
葛恒奇
Ge Hengqi(Guizhou Qiancheng Hongjing Engineering Consulting Co.,Ltd.,Guiyang Guizhou 550014,China)
出处
《山西建筑》
2026年第5期21-26,共6页
Shanxi Architecture
基金
贵州省公路局科技项目:磷石膏基低碳固废路面开发及应用研究(项目编号:2024QLK17)。
关键词
磷石膏
四元体系
力学性能
微观结构
水化产物
phosphogypsum
quaternary binder system
mechanical properties
microstructure
hydration products
