化学外加剂对粉煤灰湿法细化活化的影响  

Effect of Chemical Additives on Wet Grinding and Activation of Fly Ash

作　　者：谭洪波[1] 孔祥辉 贺行洋 李懋高 苏英 蹇守卫[1] 杨进 TAN Hongbo;KONG Xianghui;HE Xingyang;LI Maogao;SU Ying;JIAN Shouwei;YANG Jin(State Key Laboratory of Silicate Materials for Architectures,Wuhan University of Technology,Wuhan 430070,China;School of Civil Engineering and Environmental Sciences,Hubei University of Technology,Wuhan 430064,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]湖北工业大学土木建筑与环境学院,武汉430064

出　　处：《材料导报》2024年第5期184-190,共7页Materials Reports

基　　金：湖北省重点研发计划项目(2021BAA060)。

摘　　要：将粉煤灰(FA)作为矿物掺合料使用,是降低胶凝材料碳排放的重要手段之一,但其早期活性低是学者们普遍关注的问题。本研究提出在湿磨过程中引入化学功能组分来提升FA细化活化效率的技术思路;通过激光粒度仪(PSD)、pH仪、全谱直读等离子体发射光谱仪(ICP)、XRD、SEM和TG-DTG等测试手段评价了FA的物化性能及活性指数,揭示了液相研磨机械力和化学溶蚀协同作用机理。结果表明:引入TIPA、TEA、NaOH、Na_(2)SO_(4)及电石渣(CS)化学功能组分优化了湿磨的液相环境介质,可显著提升湿磨效率;当FA的中值粒径降低至2μm时,TIPA+CS作用效果最为显著,研磨时间由原来的120 min缩短至40 min,缩短67%。从活性指数的角度来看,1 d龄期时,Na_(2)SO_(4)作用效果最为显著,湿磨FA的活性指数达到60.1%;3 d、7 d、28 d龄期时,TIPA+CS作用效果较好,湿磨FA的活性指数分别可达到81.3%、89.1%、97%。在液相研磨机械力作用过程中,液相环境介质可溶蚀粉煤灰表面,促进表面[AlO_(4)]和[SiO_(4)]的解聚,加速离子溶出,形成钙矾石、C-S-H凝胶等水化产物,显著提升FA的湿磨细化活化效率。Fly ash (FA), used as mineral admixture, is one of the important means to reduce carbon emission of cementitious materials, but its low early activity is a common concern. In this study, chemical functional components were introduced in wet grinding process to improve the efficiency of FA refinement and activation. The physicochemical property and activity index were evaluated by PSD, pH, ICP, XRD, SEM and TG-DTG, and the synergistic mechanism of liquid lapping mechanical force and chemical dissolution was revealed. The results show that the introduction of TIPA, TEA, NaOH, Na_(2)SO_(4) and carbide slag (CS) chemical functional components and optimization of liquid environment medium could significantly improve the wet grinding efficiency. When the median particle size of FA was reduced to 2 μm, TIPA+CS had the most significant effect;the grinding time was reduced from 120 min to 40 min, with a decrease by 67%. At 1 day age, Na_(2)SO_(4) showed the most significant effect, and the activity index of FA reached 60.1%;at 3 d, 7 d and 28 d, TIPA+CS had a good effect, and the activity index reached 81.3% , 89.1% and 97%, respectively. In the process of wet grinding process, liquid environment medium could corrode the surface of fly ash, promote the depolymerization of [AlO_(4)] and [SiO_(4)] on the surface, accelerate ion dissolution, form hydration products such as ettringite and C-S-H gel, and significantly improve the efficiency of refinement and activation.

关 键 词：粉煤灰 湿法研磨 液相环境 掺合料 活性指数 

分 类 号：TU528[建筑科学—建筑技术科学]