浓密尾矿管道输送的研究现状及展望

为掌握浓密尾矿管道输送中的流动规律及阻力特性,对国内外现有研究成果进行了综述,以尾矿颗粒的粒径尺寸和分布特征为切入点,分析了颗粒-颗粒、颗粒-流体间的相互作用,提出将浓密尾矿管道输送划分为均质结构流和复合流动两种模式,分别对不同模式下浆体流变性质、颗粒运移行为、流动型态及阻力特性方面的研究成果和最新进展进行了评述。结果表明:均匀细颗粒(d dc)浓密尾矿可视为由细颗粒介质与离散粗颗粒组成的复合流体,粗颗粒具有"剪切沉降"效应,介质屈服应力较小(τy<5τyc)时,浆体在管道内分层流动,管流阻力可通过两层流模型进行分析。

Current status-in-situ and the prospect of the pipeline transportation of the thickened tailings

The present paper intends to conduct a comprehensive analysis and discussion over the research status of the pipe-transferring flow of the thickened tailings from the point of view of the tailing size and the interaction between the solid particles and the fluids.In given paper,the pipe flow patterns of the thickened tailings can be classified into 2 categories,that is,the flow of the homogeneous structure and the hybrid flow in reference to the engineering design and the pipeline transport system optimization.On such a basis,we have reviewed and discussed the current research status on the rheological properties,the particle migration behavior,and the pipe flow friction loss.The research results we have gained show that there has been a critical particle diameter dc.When the particle size of the tailings is smaller than dc(ddc).The coarse particles tends to settle down in the sheared flows and leads to form a stratified flow with its flow in the pipe.The pipe friction loss of the hybrid fluid is not only related to the rheological properties of the carrier fluid,but also affected by the bed movement,which can be analyzed by a 2-layer flow model.And,finally,some suggestions on the future research of the thickened tailings pipeline transportation should be brought about,including establishing a rheological test standard,developing some visualization detection techniques,further research on the turbulent pipe flow,and improving the numerical simulation methods in terms of overcoming the inefficiency of the given research.