X射线衍射法分析水镁石煅烧制备的镁砂物相组成

Analysis of Phase Composition of Magnesite Clinker from Calcinated Brucite by X-ray Diffraction

摘要: 采用X射线衍射技术 (XRD) 对水镁石原矿和不同工艺条件生产的出口镁砂产品进行了物相组成分析，水镁石原矿粉中主相Mg(OH)₂含量达到85.9%，杂质主要是Mg₃Si₂(OH)₄O₅、CaCO₃和CaMg(CO₃)₂；轻烧镁砂中的Mg(OH)₂大部分已经分解为MgO，但还有12.3%的Mg(OH)₂未分解，并在低温煅烧的情况下生成了微量的新相Mg₂SiO₄；重烧镁砂中的Mg(OH)₂已经完全分解为MgO，杂质主要存在形式是Mg₂SiO₄和CaCO₃，占总量的18.5%。实验结果将成为提高水镁石矿煅烧生产的镁砂品质而改进提纯工艺的参考依据。

Abstract: The X-ray diffraction (XRD) has been used to analyze phase composition of magnesite clinker from calcinated brucite with different process conditions. The major phase of raw brucite powder is Mg(OH)₂ with content up to 85.9% and major impurities are Mg₃Si₂(OH)₄O₅, CaCO₃ and CaMg(CO₃)₂. Most of Mg(OH)₂ are decomposed into MgO under light calcined condition (700~1000℃) during the calcination at low temperature and about 12.3% of un-decomposed Mg(OH)₂ forms new phase of Mg₂SiO₄. Mg(OH)₂ in brucite is completely decomposed into MgO under dead-burned condition (1400~1800℃) and the impurities are Mg₂SiO₄ and CaCO₃ with total content of 18.5%. The results provide the guidance for reforming purification process and improving the quality of magnesite clinker.