黄铁矿氧化对尾矿库的影响初探

Effect of Pyrite Oxidation on Tailings Reservoir

黄铁矿氧化产物是影响尾矿坝稳定性和环境的重要因素之一,根据栗西尾矿坝工程地质勘察和大量的试验数据,结合尾矿矿物成分、化学成分分析和实验柱模拟试验,对尾矿坝16年期间相同位置的尾矿重金属离子迁移、物理力学性质变化规律进行了研究。黄铁矿氧化对尾矿库的影响表现在:使库水酸化;黄铁矿氧化产物对尾矿的影响主要在浅层,使其砂粒含量减少,粉粒、黏粒的含量增多,干密度和比重增大,孔隙比变大,而渗透系数下降;重金属离子迁移,表层氧化带Mn、Mo、Zn的流失约86%、39%、90%;使尾矿渗透系数和坝体排渗设施效能降低。该研究结果对于其他硫化矿山研究和治理具有重要的借鉴意义。

Pyrite oxidation products are one of the important elements affecting the stability and environment of tailings dam. Based on the geological investigation and a large number of experimental data of Lixi Tailings Dam, this paper studies the variation rule of heavy metal ion mobility and physical-mechanical properties of tailings in one spot during the past 16 years, combining with mineral composition and chemical composition analysis and experimental column simulation experiment. The effects of pyrite oxidation on the tailings reservoir are demonstrated： acidifying the tailings water; the influence of pyrite oxidation products on the tailings is mainly demonstrated in the shallow layer by reducing its sand content and increasing silt and clay contents with the accompanied increased dry density and gravity, enlarged void ratio and decreased permeability coefficient; migration of heavy metal ions with the loss rates of Zn, Mo and Mn in the surface layer are about 86 %, 39 % and 90 %respectively; reducing the permeability coefficient and the efficiency of the dam drainage facilities. The research shed some light on the pollution treatment of sulfide mines.