Release Law And Microstructure Evolution Of Contaminants In Iron Ore In Chemical Solution

According to the key scientific problems in the monitoring process of mine tailings slag pollutant emission reduction in the mining area,a series of indoor model tests were carried out around the release law of iron ore slag pollutants under the action of chemical solution,mainly based on indoor immersion test.The macroscopic and microscopic studies of slag and slag contaminants reveal the release of iron ore slag contaminants under the action of chemical solutions by measuring the change of metal ion concentration in slag over time and the microscopic characteristics of slag-like and immersion liquid suspensions.The law provides a theoretical basis for the control and treatment of tailings reservoir pollutants.The main results of this paper include the following aspects:(1)The physical and mechanical parameters of the slag are measured by geotechnical test.The slag sample after soaking is passed through the direct shear test.The internal friction angle of the slag sample is measured with the change of the immersion depth.The upper and middle layers of the slag sample after the solution immersion are rubbed.The angle is obviously reduced;the permeability coefficient of the slag sample is measured by the permeation instrument as the immersion depth changes,the slag sample after the solution immersion,the permeability coefficient of the upper layer and the middle layer slag sample is significantly reduced,and the permeability coefficient of the slag in the neutral solution is reduced.The magnitude is small.(2)Using an indoor immersion test,immersing the slag sample in a solution with pH=3,pH=5,pH=7,pH=9,pH=12,respectively,measured by atomic absorption spectrophotometer The ion concentrations of Ca2+,Fe2+,Mg2+ and Cd2+ in the slag soaking solution were soaked for 1d,3d,5d,10d,20d and 30d,and the order of metal ion release in the slag and the concentration of each technical ion release were obtained.(3)X-ray diffractometer mineral composition analysis and scanning electron microscopy analysis of the slag sample after soaking and the suspended matter in the soaking solution.The XRD curve of the slag shows distinct diffraction angles and peaks.The sample immersed in the acidic solution is basically consistent with the untreated slag.The diffraction angle and the peak value of the slag sample in the neutral alkaline solution change significantly.The slag surface and pores immersed in the acidic solution were significantly more than the samples immersed in the alkaline solution.The suspended matter in the acidic solution is wide,and the apparent characteristics are similar to those of the slag sample soaked in the acidic solution.The apparent characteristics of the suspended matter in the alkaline solution are significantly different,and a large amount of spherical matter is produced.(4)Using COMSOL MultipHysics 5.4 to construct a model of solute injection in porous media,fitting the metal ion release curve to a function of concentration boundary conditions,transmitting in the sand layer by advection and dispersion,and discovering metal ion penetration over time.The depth and the concentration of ions in the sand layer vary at various depths.