铝酸钠对磷石膏矿渣干硬水泥性能的影响机理  

Influence Mechanism of Sodium Aluminate on Properties ofPhosphogypsum Slag Dry-Hard Cement

作　　者：唐佩 文嘉祺 陈伟[1] TANG Pei;WEN Jiaqi;CHEN Wei(State Key Laboratory of Silicate Materials for Architectures,Wuhan University of Technology,Wuhan 430070,China;School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]武汉理工大学硅酸盐建筑材料国家重点实验室,武汉430070 [2]武汉理工大学材料科学与工程学院,武汉430070

出　　处：《硅酸盐通报》2024年第8期2924-2932,共9页Bulletin of the Chinese Ceramic Society

基　　金：国家重点研发计划项目(2022YFC3902705);湖北三峡实验室重点研发计划项目;湖北三峡实验室开放基金(SC211004);武汉市知识创新专项曙光计划项目(2022020801020185)。

摘　　要：磷石膏矿渣水泥是一种低碳水泥,该体系中反应物矿粉的溶出速度较慢,导致凝结时间长,早期强度低。降低水灰比并使用干压成型方式制备干硬水泥,通过颗粒的紧密堆积提供初始强度,但极低的水灰比使反应进行缓慢,因此提出通过外掺铝酸钠促进早期产物产生及后期矿渣水化。通过抗压强度、水化放热、物相分析以及微观形貌观测研究外掺铝酸钠对干硬水泥性能的影响。结果表明,铝酸钠的掺入能够促进磷石膏矿渣干硬水泥水化的进行,且在早期生成更多的水化产物以提升强度的发展,后期能促进矿粉的持续水化,掺加铝酸钠试块在各个养护龄期的强度均高于对照组,掺量为混合粉体质量的0.5%时效果最佳。Phosphogypsum slag cement is a low-carbon cement.The dissolution rate of slag in this system is slow,resulting in low early-age strength and long setting time.Reducing the water-cement ratio and using dry pressing molding method can improve its early-age properties by dense packing of particles.However,the very low water-cement ratio of dry-hard cement slows down the hydration process in long term.Therefore,the use of the additional sodium aluminate to promote the production of hydration products in early age and the hydration of slag in later age was proposed in this study.The effect of sodium aluminate on the compressive strength,hydration process,phase assemblages and micromorphology of phosphogypsum slag dry-hard cement were studied.The results show that the hydration process is promoted,and more hydration products are produced in early age resulting in the increasing compressive strength.The hydration of slag in late age is improved and the strength of sample with sodium aluminate is higher than reference sample in all curing ages.The optimized content of additional sodium aluminate is 0.5%(by mass of total powder).

关 键 词：磷石膏 干硬水泥 铝酸钠 水化产物 钙矾石 物相分析 

分 类 号：TQ172.1[化学工程—水泥工业]