膏体充填技术越来越多地被用于地下矿山开采中,膏体的流变特性是保证膏体顺利输送及充填的基本特征参数.传统膏体的流变特性分析主要以室内流变仪测试为主,测试结果与现场实际存在较大误差.因此为了获得膏体充填料浆输送过程中真实的流变特性,本研究基于流体力学理论对膏体管道流动过程中的受力状态进行了分析,设计了倾斜管道实验装置.借助均匀设计实验方法,研究了膏体质量分数、灰砂比、细粒尾矿添加量、粗颗粒添加量4种因素对某矿膏体流变特性的影响,得到了各因素关于浆体屈服应力及塑性黏度的函数关系.结果表明:对于层流状态下的宾汉流体,利用倾斜管道装置,能够简单、快捷地测定其相关的流变参数;浆体质量分数对流变参数起决定性作用,而灰砂比的影响可忽略,当细粒尾砂掺量12%,碎石掺量4%时,膏体具有较低的屈服应力及塑性黏度,其流动性较好.
Paste filling techniques are increasingly being used in underground mining,and rheological properties of the paste is the basic characteristic parameters to ensure its smooth delivery and filling.Analysis of the rheological properties of traditional paste mainly relies on indoor rheometer,and there will be sizeable deviations between the test results and the actual site.Therefore,in order to obtain real rheological properties of paste filling slurry in transportation process,this paper analyzed stress state during paste pipeline flow based on hydrodynamic theory,designed incline pipeline experimental device.Studied the paste mass fraction,gray sand ratio,the amount of fine tailings added,the amount of coarse particles added four kinds of factors affect on rheological properties of a mineral paste with the help of uniform design experimental methods.A function of various factors on the slurry yield stress and plastic viscosity was obtained.The results showed that:for Bingham fluid under laminar flow conditions,use incline plumbing device can be easily and quickly measure the relevant rheological parameters;slurry mass fraction play a decisive role on rheological parameters,and the impact of gray sand ratio can be ignored,when the fine tailings content 12%,gravel content 4%,the paste has a low yield stress and plastic viscosity,good fluidity.