Numerical Simulation Of Liquid Collection And Surface Landslide Law Of In Situ Leaching Of A Rare Earth Mine In Southern Anhui Province

At present,in-situ leaching mining technology is widely used in ion-absorpted type rare earth ore,has achieved good economic benefits in the process of mining.However,there are still many problems.For example,the poor effect of using the diversion hole to collect the liquid has led to the waste of the precious rare earth.Besides,the landslide often takes place in the process of the injection fluid,which may result in the financial loss and safety accidents.In this paper,it had performed related research about the recycling effect of the dense flow guide hole and slope surface cracks and surface landslide,combining with the research situation in a mine of Xinfeng county in Ganzhou.At the scene of the mine,the natural density and water content of the soil at different depths were tested;and the natural permeability coefficient of the soil at different depths was tested with the single-ring method;then liquid volume of fluid diversion hole,liquid injection quantity of the injection and the height of the ore block infiltration line were tested in the mining field.Based on the testing results above,the recovery rate of the dense diversion holes in the mining area was calculated.In the indoors experiment,the cohesion of the topsoil and the ore mines were tested by using GDS vibration triaxial apparatus with the soil taken from the testing field.Though the fast shear test,internal friction angle of mine topsoil and seam were tested by strain direct shear apparatus.With Geo Studio2007 numerical calculation software and the soil parameters measured in the test,it found out the basic model to carry on the different intensity of liquid range under different injection liquid surface patterns of landslide.And according to the two cracks,the slope of the terrain model was build to calculate the landslide critical water level.Then the conclusions were drawn as follows:(1)The vertical height between underground water surface and liquid receiving port of diversion hole is about 0.5 to 2 meters.When the formation of ore block is stable,the recovery rate of the dense flow diversion hole is 75.38%.(2)When the injection range was greater than 40% and the liquid injection intensity was greater than 0.8 square meters per day,conditions were prone to landslide and the depth might be up to 4 to 6 meters.,and the height of the cut exports was about 10 to 13 meters.(3)When the injection range was less than 30% and the liquid injection intensity was greater than 0.6 square meters per day,landslide maximum depth and the cutting export highly changed little,the depth of the landslide was about 8.38 meters,and the height of the cut exports was about 8.68 meters.(4)By observing the height of liquid level in ore block through the injection hole and then controlling the injection strength,it could effectively prevent the occurrence of landslide disaster.