Wang Yaguang, Liu Xiaoming, Xie Zhiqing, Wang Huimin, Zhang Wei, Xue Yang
State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China.
School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China.
Materials (Basel). 2021 Sep 24;14(19):5546. doi: 10.3390/ma14195546.
A large amount of Bayer process red mud is discharged in the process of alumina production, which has caused significant pollution in the environment. The pozzolanic activity of Bayer red mud as a supplementary cementitious material is a research hotspot. In this work, a new method for Fourier-transform infrared spectrometry is used to determine the polymerization degree of Bayer red mud in order to evaluate its pozzolanic activity. Based on the results of the dissolution concentration of (Si+Al), strength index and polymerization degree of Bayer red mud, the relationships between different evaluation methods were analyzed, and the relevant calculation formulas of pozzolanic activity were obtained. The results showed that different evaluation methods can reflect the variation law of pozzolanic activity in Bayer red mud. The polymerization degree of Bayer red mud had a good linear relationship with the pozzolanic activity index obtained by the strength index and dissolution concentration of (Si+Al), respectively. The polymerization degree was negatively correlated with pozzolanic activity index and dissolution concentration of (Si+Al), and the correlation coefficients were greater than 0.85. Therefore, this method was found to be effective and hence can be used as a rapid and simple test for pozzolanic activity evaluation of Bayer red mud.
在氧化铝生产过程中会排放大量的拜耳法赤泥，这对环境造成了严重污染。将拜耳赤泥作为辅助胶凝材料的火山灰活性是一个研究热点。在这项工作中，采用一种新的傅里叶变换红外光谱法来测定拜耳赤泥的聚合度，以评估其火山灰活性。基于拜耳赤泥的（硅+铝）溶解浓度、强度指标和聚合度的结果，分析了不同评价方法之间的关系，并得到了火山灰活性的相关计算公式。结果表明，不同的评价方法能够反映拜耳赤泥中火山灰活性的变化规律。拜耳赤泥的聚合度分别与通过强度指标和（硅+铝）溶解浓度得到的火山灰活性指数具有良好的线性关系。聚合度与火山灰活性指数和（硅+铝）溶解浓度呈负相关，相关系数大于0.85。因此，该方法被证明是有效的，可作为一种快速简便的拜耳赤泥火山灰活性评价测试方法。
