(1. 北京科技大學(xué) 土木與資源工程學(xué)院，北京 100083；
2. 北京科技大學(xué) 順德研究生院，佛山 528399)
摘 要: 尾砂濃密中絮團結(jié)構(gòu)與絮凝效果隨絮凝條件變化發(fā)生改變，對濃密機內(nèi)沉降區(qū)固液分離效率產(chǎn)生影響，但現(xiàn)有研究少有基于尾砂絮團結(jié)構(gòu)分析絮凝條件產(chǎn)生的影響。為此，本文采用管道絮凝方式，對不同絮凝條件下形成的尾砂絮團結(jié)構(gòu)高清獲取，分析絮團等效直徑以及絮團分形維數(shù)隨之變化的規(guī)律，并對絮凝后的上清液濁度以及絮團沉降速度開展研究。結(jié)果發(fā)現(xiàn)，陰離子型聚丙烯酰胺與尾砂顆粒形成的絮團結(jié)構(gòu)最大，絮凝劑單耗、尾砂進料濃度、絮凝劑濃度和流體剪切梯度G對絮團等效直徑、絮團分形維數(shù)、上清液濁度以及絮團沉降速度產(chǎn)生重要影響。絮凝劑單耗在90~105 g/t、尾砂進料濃度在25%~30%、絮凝劑濃度小于1/10000、流體剪切梯度30~50 s-1時形成的絮團等效直徑超過1000 μm、絮團分形維數(shù)在1.64~1.68之間、絮團沉降速度均超過9 m/min、濃密機模型內(nèi)上清液濁度低于50 mg/L，絮團沉降速度加快能夠提升濃密機內(nèi)沉降區(qū)固液分離效率，該結(jié)論為膏體充填實際生產(chǎn)中控制絮凝條件參數(shù)提供了價值參考。
關(guān)鍵字: 絮團結(jié)構(gòu)；分形維數(shù)；沉降速度；上清液濁度；固液分離
（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
