含镁铝尖晶石的铝酸盐水泥的制备与应用

Preparation and application of aluminate cements containing magnesia-alumina spinel

按天然白云石(≤0.1mm)与工业氧化铝粉(≤0.088mm)的质量比为45∶55配料,经混合、成型和烘干后,于1600℃3h煅烧,细磨烧结体得到含镁铝尖晶石的新型铝酸盐水泥。测量了新型铝酸盐水泥的凝结时间、耐火度以及用其所结合高铝矾土制成的耐火浇注料的早期强度;利用XRD、SEM和EDS分析了新型铝酸盐水泥的物相组成及其形貌和分布,同时采用静态坩埚法对比了新型铝酸盐水泥和纯铝酸钙水泥结合刚玉浇注料的抗渣性差异。结果表明:新型水泥的物相组成为镁铝尖晶石(MA)、一铝酸钙(CA)和二铝酸钙(CA2),且这3个物相的分布较为均匀;新型水泥的凝结时间正常,耐火度高于纯铝酸钙水泥;用新型水泥制得的刚玉浇注料抗渣性好;其原因是新型水泥组成中引入了镁铝尖晶石相,而镁铝尖晶石具有较高的熔点和抗熔渣侵蚀能力。

Magnesia-alumina spinel （MA） containing aluminate cement was prepared using dolomite （ ≤0. 1 mm） and industrial alumina powder （ ≤0.088 mm） as starting materials by mass-ratio 45 ： 55 by mixing, shaping,drying and firing at 1 600 ℃ for 3 h. The setting time and refractoriness of the new type cement and strength of the prepared cement bonded bauxite castable were studied. By means of XRD,SEM and EDS, the phases ,morphology and distribution of the new cement were analyzed. Meanwhile, the slag corrosion resistances of corundum castables bonded with the new cement and Secar71 respectively were compared with static crucible method. The results show that.the new cement consists of MA,CA and CA2 phases, which are evenly distributed. The setting time of the new cement is normal but the refractoriness is higher and corrosion resistance to slag of corundum castable bonded with new cement is better due to the introduction of MA spinel ,which has higher melting point and corrosion resistance to molten slag.