摘要
为探究尾砂粒级组成与充填料流变特性及强度之间的关系,采用全尾砂、旋流器分级溢流和底流尾砂经人工配制成5种尾砂充填料,开展了不同粒级组成尾砂充填料流变与强度试验。结果表明:随着尾砂中-38μm细粒级含量的增加,充填料浆屈服应力和塑性黏度增加,且-38μm细粒级含量越高充填料浆屈服应力和塑性黏度增加幅度越大;随着细粒级尾砂含量的增加,水化膜厚度呈先增加后降低的变化趋势;充填料浆初始屈服应力和塑性黏度受水化膜厚度和固体颗粒比表面积的双重影响;当细粒级尾砂含量超过44.37%时,水化膜厚度与充填料浆初始屈服应力和塑性黏度之间存在负指数关系。随着细粒级尾砂含量的增加,尾砂充填体强度先增加后减小,细粒级含量为44.37%时为尾砂最佳粒级组成,此时充填体中尾砂堆积所形成的骨架结构最密实,充填体总孔隙率、平均孔径和大于0.2μm有害孔占比最小。
To investigate the correlation between the particle size distribution of tailings and the rheological properties and strength of cemented tailings backfill(CTB),five different types of CTBs were artificially prepared using full tailings,cyclone overflow,and underflow tailings.Rheological and strength tests were conducted on the CTBs,and changes in the internal pore structure of the tailings backfill were analyzed using mercury intrusion methods(MIP).The impact of the particle size distribution of tailings on the rheological properties,strength,and microstructural characteristics of CTBs were assessed.The findings indicate that an increase in fine tailings content by-38μm results in higher rheological parameters(yield stress and plastic viscosity)of fresh CTBs,with a greater increase observed at higher fine tailings content levels.The variation in particle size distribution of tailings leads to noticeable differences in the thickness of water film of solid particles in the backfilling slurry.Specifically,an initial increase followed by a subsequent decrease in water film thickness is observed with increasing fine tailings content.The initial yield stress and plastic viscosity of backfilling slurry are influenced by the water film thickness and specific surface area of solid particles.An exponential relationship is observed between the initial yield stress and plastic viscosity of CTB when the fine tailings content exceeds 44.37%.The strength of CTB initially increases and then decreases as the fine tailings content increases.The fine tailings content of 44.37%represents the optimal particle size distribution of tailings.In this condition,the compactness of the skeleton structure of the CTB formed by the accumulation of tailings is at its maximum,resulting in the lowest values for total porosity,average pore size,and the percentage of harmful pores larger than 0.2μm.
作者
盛宇航
裴佃飞
齐兆军
荆晓东
SHENG Yuhang;PEI Dianfei;QI Zhaojun;JING Xiaodong(Shandong Gold Mining Technology Co.,Ltd.,Jinan 250000,Shandong,China;Shandong Key Laboratory of Deep-sea and Deep-earth Metallic Mineral Intelligent Mining,Jinan 250000,Shandong,China;Shandong Gold Group Co.,Ltd.,Jinan 250000,Shandong,China)
出处
《黄金科学技术》
CSCD
北大核心
2024年第4期631-639,共9页
Gold Science and Technology
基金
国家重点研发计划项目“深部低废高效机械化充填采矿技术研究”(编号:2018YFC0604601)资助。
关键词
尾砂粒级组成
胶结充填料
流变特性
水化膜厚度
强度
孔结构
particle size composition of tailings
cemented tailings backfill
rheological characteristics
water film thickness
strength
pore structure
