Experimental Study On Engineering Properties Of Rare Earth Mine After In Situ Leaching

Gannan is the main part of the ionic rare earth in the southern which reserves make up of about90%of the reserves of jiangxi province rare earth. Rare earth mine are widely distributed in the xun wu, longnan, xinfeng, anyuan, dingnan, quannan,ningdu,ganxian and other counties, total more than80mining areas.The mining technology of ion absorpt deposit is special in the southern, that is using ammonium sulfate leaching solution to leach ore in order to get rare earth element ion exchange liquid. However, this technology of solution mining is easy to cause serious soil erosion and environmental pollution. As country to pay more and more attention to environmental protection, we made continuous improvement of mining technology, from the first generation of heap leaching process to the second generation of mining pool leaching process and the national promotion of the third generation of in-situ leaching mining method of mining technology. In spite of in-situ leaching mining method on the surface to reduce the damage to the vegetation, it is prone to landslides in the process of mining and after mining in mines.This article is one part of the research achievement of’the earthy engineering properties in rare earth mining area after in-situ leaching mining and its influence on traffic engineering’(Jiangxi bureau of science and technology plan projects). Mainly has carried out the following work:(1) First, reviewed the research status of soil pollution, summarizes predecessors’research achievements and problems to be studied in the future, which definitely need further research.(2) Prepare ammonium sulfate solution contaminated soil samples, make the soil sample soaked in3%concentration of ammonium sulfate solution respectively, observe leaching soil samples before and after mining and pollution solution appearance changes, and determine the change of the inner mineral composition of soil before and after pollution, explain the soil chemical corrosion mechanism.(3) Determine the moisture content, specific gravity, density, liquid plastic limit and the coefficient of compression, compression modulus, cohesive and internal friction Angle of soil before and after leaching mining pollution, use the FLAC3D numerical software to evaluate the parametric variation of soil mechanics to the slope stability’s impact before and after ore leaching reaction.(4) Study on steel corrosion test with rare earth samples after mineral leaching; determine weight loss ratio after the rare earth on corrosion of steel under the different leaching ore days.Through the study of soil basic properties after in-situ leaching mining in rare earth mining area,the mechanism of rare earth leaching liquid and soil-water and its impact on soil property, it provide a quality guarantee in building highway engineering, also will provide the basis for engineering design and construction.