石煤提钒预富集分离过程中的松散-分层模型

摘要

A technology of one-stage roughing and one-stage scavenging vanadium pre-concentration with shaking table was investigated for improving vanadium grade and decreasing acid consumption minerals content based on the quantitative evaluation of minerals by scanning electronic microscopy (QEMSCAN). In order to visually illustrate how the vanadium-bearing minerals were separated from system, a loose-stratification model was established with Bagnold shear loose theory and Kelly stratification hypothesis. Through the model, it was inferred that fine fraction and coarse fraction of vanadium-bearing muscovite particles easily became the concentrate in roughing and scavenging stages, respectively. The type of the dominant effect on the loose-stratification was confirmed. In the roughing stage, gravity sedimentation played a leading role in the loose-stratification process. However, in the scavenging stage, shearing dispersion pressure caused by asymmetric motion of table deck took an important part in the loose-stratification process. Finally, the correction of the loose-stratification model was validated by the practical experiment.%在扫描电镜矿物定量评价(QEMSCAN)工艺矿物学研究的基础上，采用摇床分选工艺对石煤中的钒进行预富集，以实现提高钒品位的同时，降低耗酸矿物的含量；并利用Bagnold剪切理论和Kelly分层假说建立分离过程中的松散-分层模型，以阐述含钒基体矿物从分选体系中分离的机理，且对模型进行验证。模型结果表明，细粒级含钒基体矿物和粗粒级含钒基体矿物分别在粗选和扫选阶段实现分离；在模型计算过程中确定了影响粗选和扫选阶段分离的主导因素，分别为重力沉降和摇床床面的不对称往复运动产生的剪切分散压。