The Critical Factors and Preventive Measures of Impoundment of Tailings Using Active Surface Subsidence Zones

Impoundments of tailings and active surface subsidence zones induced by ore mining were the major environmental problems. The aim of this study was to investigate the technical feasibility of impoundment of tailings using active surface subsidence zones. The self-designed scaled physical model was conducted to investigate the movement laws of tailings under different heights of granular media and tailings, and then drawing ore in these experiments was performed to simulate the mining process. The experimental results showed that the isolated extraction zone and stoping sequence had a primary influence on the doping process of tailings. Besides, when the height of granular media was more than that of the isolated movement zone, the uniform mode of drawing ore could be decreased the amounts of tailings drawn from drawpoints. Meanwhile, the doping process was not impacted by continuously emission of tailings to active surface subsidence zones. Thus, the field test was employed in the Dabeishan Iron Mine and the mining schemes were put forward based on the experimental data. The results showed that the recovery ratio and dilution ratio were 80.9% and 24.3% respectively, and that the scheme established in this paper could be used in practice.