摘要
Based on Bingham rheological model,a three-dimensional numerical simulation model for long-distance pipeline transportation is established by computational fluid dynamics(CFD)to study the pipeline transportationproperties of high sliming paste from a copper mine in China.Based on the rheological properties test,the pressure and velocity of pipeline and elbow are simulated by CFD under different mass concentrations and different stowing capacities.The results show that the pipeline resistance of whole-tailings paste with high sliming while without pumping agent is much higher than that with high sliming and pumping agent at the same mass concentration,and the pipeline resistance of whole-tailings paste with high sliming while without pumping agent is much higher than that with low sliming while without pumping agent.It is very important to add pumping agent to whole-tailings paste with high sliming,and the resistance changes with mass concentration and stowing capacity at the same cement-to-sand ratio of1:5and tailings-to-waste ratio of6:1.However,the change is just limited,that is to say,the paste transportation system is of good stability.Furthermore,at the elbow,the maximum pressure and velocity transfer to the outside of the pipe from the inside.However,lubricating layer is formed at the pipe wall because of high content of fine particles in whole-tailings paste,which will protect the elbow from abrasion.CFD provides an intuitive and accurate basis for pipeline transportation study,and would have a wider application space in the study of paste rheological properties and resistance reduction methods.
针对高含泥膏体管道输送特性研究问题,以国内某铜矿为研究对象,基于宾汉姆流变模型,运用计算流体力学(CFD)建立高含泥膏体长距离管道输送性能研究的3D数值分析模型。在室内流变特性试验的基础上,对不同浓度、不同充填能力料浆输送中管道和弯管处压力、速度进行CFD模拟分析。结果表明:不添加泵送剂的高含泥膏体的管道输送阻力损失远高于添加泵送剂的高含泥膏体阻力损失和不添加泵送剂的低含泥膏体阻力损失,这对于高含泥膏体添加泵送剂尤为重要。当灰砂比为1:5、尾废比为6:1、浓度为73%–76%时充填能力为70–110 m3/h,阻力损失变化不大,输送系统相对稳定。通过弯管处压力、速度模拟可得,管道内压力和速度最大值点由管道中心线向管道内下侧方偏移。但是由于细粒级颗粒含量高,在管壁处形成润滑层,对弯管有一定的保护作用。CFD能够为膏体管道输送研究提供直观准确的依据,在膏体流变特性和降阻方法创新方面还有更为广阔的应用空间。
基金
Project(2016YFC0600709)supported by the National Key R&D Program of China
Project(51574013)supported by the National Natural Science Foundation of China
Project(FRF-TP-17-024A1)supported by the Fundamental Research Funds for the Central Universities,China
