以活性石灰(≤20 mm)为原料,消化得到Ca(OH)2细粉(d50=8.28 μm),以Al2O3(≤ 0.074 mm)为添加剂,制得CaO砂.研究了Al2O3的加入量及煅烧温度对CaO砂烧结性能的影响.采用XRD检测物相,结合热力学软件Factsage?6.2模拟物相变化过程,采用SEM分析试样的显微结构.实验结果表明:(1)添加2-4wt.% Al2O3的试样的体积密度较大,显气孔率较低.(2)空白样的主要物相是方钙石,随着Al2O3的增加又生成了3CaO·Al2O3,且衍射峰逐渐增强.(3)1500 ℃时,添加2wt.% Al2O3的试样晶粒尺寸最大,为37.3 μm;4%次之,为34.9 μm.而含4wt.%Al2O3的试样在1450 ℃、1500 ℃和1550 ℃烧后的晶粒尺寸分别为33.3 μm、34.9 μm和36.3 μm.当煅烧温度增加到1500 ℃时试样已经达到较大的晶粒尺寸,且其体积密度最大,继续提高温度对晶粒尺寸增加不大,反而会降低体积密度.%CaO clinker was prepared using Ca(OH)2as raw material, which was obtained by active lime, and Al2O3as additive. The effects of Al2O3content on sintering properties of CaO clinker was carried out in this paper. XRD was used to determine the mineral phases, and thermo-chemical simulation of phase change during heat process was carried out through FactSage? 6.2 software. SEM and EDS characterization method were performed to analyses microstructure of CaO clinker . The results showed that: (1) The sample with 2-4wt.% Al2O3has lower apparent porosity, and higher bulk density; (2) The main phase of blank sample is CaO. New phase of 3CaO?Al2O3is formed and it's diffraction peaks are gradually enhanced with the increase of Al2O3amount;( 3) The average grain size of the samples with 2-4 wt.% Al2O3fired at 1500 ℃ is 37.3 μm, 34.9 μm, respectively. The average grain size of CaO samples with 4 wt.% Al2O3fired at 1450 ℃, 1500 ℃, 1550 ℃, is 33.3 μm, 34.9 μm, 36.3 μm, respectively. When the firing temperature increased to 1500 ℃, the sample has larger grain size, and its bulk density reaches the largest. However, further increasing temperature has slightly effect on the grain size, and has negative effect on bulk density.
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