Partical Size Distribution Law And Stability Analysis Of Tailings Under Hydraulic Separation Condition

In order to investigate the effects of different slurry velocity and concentration on the sedimentation of tailings and the stability of the reservoir after deposition,The distribution of particle size distribution of tailings under different pretreatment speed and concentration was studied by the combination of indoor test and numerical simulation.And a reasonable way of sorting for the actual situation was selected to meet the stability of the tailing dam.The main findings are as follows:(1)On the basis of the theory of solid-liquid two-phase flow,The theoretical relationship between the critical particle size and the concentration and velocity of the slurny is deduced by the moment balance equation and the force balance equation.The critical particle size decreases with the decrease of slurry concentration and slurry velocity;(2)Through the different slurry speed and concentration of tailings particle size distribution of deposition test,it is getted that the larger the rate of slurrying,the smaller the concentration,the farther away from the tailings movement of the tailings particles,the steep slope of the sedimentary slope;(3)Through the sampling and sedimentation of different size tailings of different granulation speed and concentration,the solidification and consolidation and solid shear test were carried out.The relationship between the particle size,the porosity and the vertical pressure is obtained,and the relationship between the tailings,the vertical pressure and the permeability coefficient is obtained;(4)The fluid-solid coupling mechanics model considering stress effects of variable porosity is established,and the concentration and velocity of tailings are optimized by numerical simulation.(5)Optimized discharge guidance field of a tailings slurry discharge The vertical pressure,displacement,pore water pressure,seepage point and safety factor were calculated in three cases of normal,flood and early dam clogging.It is confired that slurry discharge way can meet safety standards.