(1. 北京科技大学 土木与资源工程学院，北京 100083；
2. 北京科技大学 顺德研究生院，佛山 528399)
摘 要: 尾砂浓密中絮团结构与絮凝效果随絮凝条件变化发生改变，对浓密机内沉降区固液分离效率产生影响，但现有研究少有基于尾砂絮团结构分析絮凝条件产生的影响。为此，本文采用管道絮凝方式，对不同絮凝条件下形成的尾砂絮团结构高清获取，分析絮团等效直径以及絮团分形维数随之变化的规律，并对絮凝后的上清液浊度以及絮团沉降速度开展研究。结果发现，阴离子型聚丙烯酰胺与尾砂颗粒形成的絮团结构最大，絮凝剂单耗、尾砂进料浓度、絮凝剂浓度和流体剪切梯度G对絮团等效直径、絮团分形维数、上清液浊度以及絮团沉降速度产生重要影响。絮凝剂单耗在90~105 g/t、尾砂进料浓度在25%~30%、絮凝剂浓度小于1/10000、流体剪切梯度30~50 s-1时形成的絮团等效直径超过1000 μm、絮团分形维数在1.64~1.68之间、絮团沉降速度均超过9 m/min、浓密机模型内上清液浊度低于50 mg/L，絮团沉降速度加快能够提升浓密机内沉降区固液分离效率，该结论为膏体充填实际生产中控制絮凝条件参数提供了价值参考。
关键字: 絮团结构；分形维数；沉降速度；上清液浊度；固液分离
（1. School of Civil and Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China;
2. Shunde Graduate School, University of Science and Technology Beijing, Foshan 528399, China）
Abstract:The floc structure and flocculation effect of tailings thickening change with the flocculation conditions, which affects the solid-liquid separation efficiency in the settlement zone of thickener, but few existing studies analyze the effect of flocculation conditions based on the floc structure. For this reason, the structure of tailing sand flocs formed under different flocculation conditions was obtained in high definition by using pipeline flocculation, the changes of floc equal diameter and floc fractal dimension with flocculation conditions were analyzed, the turbidity of supernatant and the settling rate of flocs under flocculation conditions were studied. The results show that the anionic polyacrylamide forms the largest floc structure with tailing particles, the flocculant dosage, tailings slurry concentration, flocculant concentration and fluid shear gradient G have important effects on floc equal diameter, floc fractal dimension, supernatant turbidity and floc settling velocity. When flocculant dosage is in the range of 90-105 g/t, tailings slurry concentration is in the range of 25%-30%, flocculant concentration is less than 1/10000 and fluid shear gradient is in the range of 30-50 s-1,the equal diameter of flocs is more than 1000 μm, the fractal dimension of flocs is between 1.64 to 1.68, the settling velocity of flocs exceeds 9 m/min and the turbidity of supernatant in the thickener model is less than 50 mg/L. The faster floc settling velocity can improve the solid-liquid separation efficiency in the settling area of thickener. This conclusion provides a valuable reference for controlling the parameters of flocculation conditions in actual production of paste filling.
Key words: floc structure; fractal dimension; settling velocity; supernatant turbidity; solid-liquid separation
