Haghdani Shokouh, Tangstad Merete, Einarsrud Kristian Etienne
Department of Materials Science and Engineering, Norwegian University of Science and Technology (NTNU), 7034 Trondheim, Norway.
Materials (Basel). 2024 Aug 1;17(15):3789. doi: 10.3390/ma17153789.
The relationship between slag structure and viscosity is studied, employing Raman spectroscopy for the five-component slag system of MnO-SiO-CaO-AlO-MgO and its subsystems. This study aims to investigate the influence of variations in slag composition on viscosity, which is crucial for optimizing industrial processes. Based on industrial slag compositions produced in a silicomanganese submerged arc furnace, 17 slags with a fixed content of MnO of 10 wt% are synthesized with varying contents of SiO of 33 to 65 wt%; CaO within the range of 14 to 40 wt%; and fixed contents of AlO and MgO of 17 and 6 wt%, respectively. The slag compositions are divided into four groups, ranging from low basicity (0.38) to high basicity (0.80), with each group containing the four slag systems of MnO-SiO-CaO, MnO-SiO-CaO-AlO, MnO-SiO-CaO-MgO, and MnO-SiO-CaO-AlO-MgO, with fixed basicity. Additionally, a five-component composition with the lowest basicity of 0.28 is considered. Raman spectroscopy measurements are performed in the wavenumber range of 200 to 1200 cm-1 using a green source laser with a 532 nm wavelength. The high-wavenumber region of the Raman spectra (800 to 1200 cm-1) is deconvoluted to quantitatively investigate the effect of each oxide on the slag structure and the degree of polymerization (DOP) of the silicate network. Results indicate that measured NBO/T increases with increasing basicity, demonstrating a reduction in DOP of the silicate structure. This depolymerization effect is more pronounced in slags containing AlO compared to those without it. In a group of slags with similar basicity, the substitution of SiO with AlO leads to further depolymerization. In contrast, substituting CaO with MgO has little effect on the silicate structure in slags without AlO but causes depolymerization in slags containing AlO. To study the relationship between structure and viscosity, viscosity data obtained from FactSage are used as reference values. The predictions of slag viscosity using the Raman-structure model and the NBO/T viscosity model are then compared to the FactSage results. The adjustable parameters of the Raman-structure model are re-determined using the FactSage data for the studied slag compositions. The NBO/T viscosity model employs both calculated NBO/T values from the slag compositions and measured NBO/T values from the deconvolution results. The findings of this study reveal good agreement between the predictions of the Raman-structure model and the FactSage viscosity data.
采用拉曼光谱法研究了MnO-SiO-CaO-AlO-MgO五元渣系及其子体系的炉渣结构与粘度之间的关系。本研究旨在探讨炉渣成分变化对粘度的影响，这对于优化工业生产过程至关重要。基于硅锰矿热炉生产的工业炉渣成分，合成了17种炉渣，其中MnO的固定含量为10 wt%，SiO的含量在33至65 wt%之间变化；CaO的含量在14至40 wt%之间；AlO和MgO的固定含量分别为17 wt%和6 wt%。炉渣成分分为四组，碱度从低（0.38）到高（0.80），每组包含MnO-SiO-CaO、MnO-SiO-CaO-AlO、MnO-SiO-CaO-MgO和MnO-SiO-CaO-AlO-MgO四种固定碱度的炉渣体系。此外，还考虑了碱度最低为0.28的五元成分。使用波长为532 nm的绿色光源激光在200至1200 cm-1的波数范围内进行拉曼光谱测量。对拉曼光谱的高波数区域（800至1200 cm-1）进行反卷积，以定量研究各氧化物对炉渣结构和硅酸盐网络聚合度（DOP）的影响。结果表明，实测的非桥氧/桥氧（NBO/T）随着碱度的增加而增加，表明硅酸盐结构的DOP降低。与不含AlO的炉渣相比，这种解聚作用在含AlO的炉渣中更为明显。在一组碱度相似的炉渣中，用AlO替代SiO会导致进一步解聚。相比之下，在不含AlO的炉渣中用MgO替代CaO对硅酸盐结构影响不大，但在含AlO的炉渣中会导致解聚。为了研究结构与粘度之间的关系，将从FactSage获得的粘度数据用作参考值。然后将使用拉曼结构模型和NBO/T粘度模型对炉渣粘度的预测结果与FactSage的结果进行比较。使用所研究炉渣成分的FactSage数据重新确定拉曼结构模型的可调参数。NBO/T粘度模型既采用了根据炉渣成分计算的NBO/T值，也采用了反卷积结果中的实测NBO/T值。本研究结果表明，拉曼结构模型的预测结果与FactSage粘度数据之间具有良好的一致性。
