Abstract The scope of this study is to investigate the crystallisation phenomenon of a synthetic SiO2-Al2O3-CaO-Fe2O3-MgO slag system. Firstly, the crystallised phases were predicted by thermodynamic equilibrium calculations. Subsequently, quenching experiments and confocal laser scanning microscope (CLSM) investigations were performed to validate the crystallisation characteristics of the synthetic slag system. Crystallisation kinetics was examined by isothermal quenching and continuous cooling CLSM experiments. The generated samples were analysed by microscopy, XRD, and SEM to determine the crystallised phases by their structure and chemical composition. A detailed insight of the evolution of crystal morphology growth was given. The shape of the two dominant phases: melilite and olivine were described and three-dimensional morphologies were defined for both phases. Additionally, the morphologies were quantified by length and aspect ratio measurements of individual crystals. The morphological information of the olivine and melilite phase, provided in this study, can be used as datasets for a viscosity model for partially crystallised slags. A conceptual viscosity model to be implemented in the next paper of this series, using specialised crystal morphology datasets, can serve a major contribution to forecast slag behaviour and to support the stability of industrial gasifier operation.

中文翻译：

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合成褐煤气化炉渣系统的结晶特性和晶相量化

摘要 本研究的范围是研究合成 SiO2-Al2O3-CaO-Fe2O3-MgO 渣体系的结晶现象。首先，通过热力学平衡计算来预测结晶相。随后，进行了淬火实验和共聚焦激光扫描显微镜 (CLSM) 研究，以验证合成渣系统的结晶特性。通过等温淬火和连续冷却 CLSM 实验检查结晶动力学。通过显微镜、XRD 和 SEM 分析生成的样品，以通过其结构和化学成分确定结晶相。给出了晶体形态生长演变的详细见解。两个主导相的形状：描述了黄长石和橄榄石，并为这两个阶段定义了三维形态。此外，通过单个晶体的长度和纵横比测量来量化形态。本研究中提供的橄榄石和黄长石相的形态信息可用作部分结晶炉渣粘度模型的数据集。将在本系列的下一篇论文中实施的概念粘度模型，使用专门的晶体形态数据集，可以为预测炉渣行为和支持工业气化炉运行的稳定性做出重大贡献。可用作部分结晶炉渣粘度模型的数据集。将在本系列的下一篇论文中实施的概念粘度模型，使用专门的晶体形态数据集，可以为预测炉渣行为和支持工业气化炉运行的稳定性做出重大贡献。可用作部分结晶炉渣粘度模型的数据集。将在本系列的下一篇论文中实施的概念粘度模型，使用专门的晶体形态数据集，可以为预测炉渣行为和支持工业气化炉运行的稳定性做出重大贡献。