MnO_2掺杂对硅酸盐水泥熟料烧成及矿物结构的影响

Effect of MnO_2 Foreign Oxide on the Sintering and Mineral Structure of Phosphoaluminate-portland Clinkers

本文研究MnO2掺杂对硅酸盐水泥熟料的烧成及性能的影响,以空白生料为基准,分别掺入0.1%、0.5%、1%、2%的MnO2,煅烧至1250℃、1300℃、1350℃、1400℃、1450℃,并利用化学分析、XRD、SEM、高温显微分析等方法分析。结果表明:当煅烧温度低于1400℃时,MnO2限制液相的生成,其掺量越大,易烧性越差;当煅烧温度高于1400℃时,温度起主要作用,液相大量生成,MnO2掺量对易烧性影响不大;并降低了A矿的含量,增加了B矿的含量。同时观察SEM照片,掺MnO2后熟料中C3S晶粒均大于基准样中C3S晶粒,这是因为MnO2稳定MeO45-,增大液相的粘度,富余CaO,使C3S长大速率占优势。

The effect of MnO_2 foreign oxide on the sintering and mineral structure of Portland clinkers was investigated by chemical analysis,XRD,SEM and high temperature micro analysis.Cement raw meal with 0.1%,0.5%,1% and 2% MnO_2 additives was prepared and calcined at 1250℃,1300℃,1350℃,1400℃ and 1450℃ for 30min,respectively.It is indicate that the existence of the liquid-phase is restricted due to the incorporation of MnO_2 below 1400℃,and the burnability of the samples decreases with the increase of MnO_2 content;much more liquid-phases of the samples are generated above 1400℃,but the influence on the burnability is little.The SEM results show that the grain size of C_3S in the samples with MnO_2 is larger than that of Portland clinker,which may be due to MeO^(5-)_4 being stabled by MnO_2 and increasing liquid-phase viscosity.